Early years.

Yakir was born in Kishinev, Bessarabia, Russian Empire, into the prosperous family of a Jewish pharmacist. He graduated from the local secondary school in 1914. Because of governmental restrictions on Jewish access to higher education, Yakir studied abroad at the University of Basel in Switzerland, in the field of chemistry. During World War I, he returned to the Russian Empire and worked as a turner in a military factory in Odessa, Ukraine (he was a reservist). From 1915 to 1917, he attended the Kharkiv Technological Institute. He was affected by the war and became a follower of Vladimir Lenin. In 1917, he returned to Kishinev, and in April became a member of the Bolshevik Party. He also became a member of the Bessarabian Governorate's Council, the Governorate's Committee and the Revolutionary Committee. From January 1918, he took active part in the Bolshevik seizure of power in Bessarabia. When Romania intervened to recapture Bessarabia, Yakir led Bolshevik resistance but his small force was overwhelmed by the regular Romanian army.

In the Civil War.

Yakir retreated to Ukraine and fought against Austro-Hungarian occupation forces as a commander of a Chinese regiment of the Red Army. He was severely wounded in March 1918 near Ekaterinoslav. At the beginning of the Russian Civil War between Bolshevik forces, the White Army and various other anti-Bolshevik movements, Yakir was a member of the Bolshevik Party in Voronezh Province and started his service in the Red Army as a commissar. He showed military talent and was assigned as a field commander. In October 1918, he served as a member of the Revolutionary Council of the 8th Army in the Southern Front and simultaneously commanded the Southern Front's several key formations in operations against the Don Cossacks of Pyotr Krasnov. He carried out Lenin's order of persecution against the Cossack civilians and the extermination of almost half of the male Cossack population. The war against armed combatants plus the terror against the civilians were coming together in the Russian Civil War. Encouraged by the Bolshevik theory of class struggle, Yakir, like other members of the Communist party, took part in terror. For his services, he became the second individual (after Vasily Blyukher) to receive the highest Soviet military award of that time, the Order of the Red Banner (engraved as No. 2).  In the summer of 1919, Yakir was sent to Ukraine to command the 45th Rifle Division, and in August 1919, he became the commander of the Southern Group of the 12th Army, which included the 45th and 58th Rifle Divisions. Both divisions were surrounded in Odessa by the White forces. Yakir undertook one of the most unusual Civil War military operations. He breached the encirclement and led his forces through the enemy rear for a distance of to join the Red Army in Zhitomir. Like other Bolshevik commanders who did not have military education he was assisted in this operation by former tsarist army officers on his staff but this fact does not negate his own role in planning and leading the campaign. For this campaign he received his second Order of the Red Banner, and both of his divisions received Red Banners of Honor. Yakir took part in actions against the White forces of Nikolai Yudenich in defense of Petrograd, in suppression of Ukrainian anarchist guerrilla forces of Nestor Makhno, and in the Polish-Soviet War. He was awarded the Order of the Red Banner three times (twice in 1919 and once in 1930), and he became one of the most-decorated Red Army commanders.

Military reform.

After the war, Yakir commanded army formations in Ukraine. Yakir was a close associate of Mikhail Frunze and belonged to his inner circle of innovative Red Army officers who assisted Frunze in starting far-reaching military reforms. Among these reformers was Mikhail Tukhachevsky who became Yakir's friend. In April 1924 Yakir was appointed a head of Main Directorate of Military Academies of the Red Army and simultaneously editor of a major military periodical devoted to development of military theory, "Voennyi Vestnik".  In November 1925, after Frunze's death, Yakir was appointed commander of the most powerful territorial formations of the Red Army, the newly reorganized Ukrainian Military District (see: Kiev Military District). Yakir, in close coordination with Tukhachevsky and other reformers, made his district into a laboratory of wide-ranging experiments in strategy, tactical and operational techniques, army formations and equipment. In training his troops, Yakir encouraged his officers' initiative and ability to make their own judgments. In 1928 and 1929, Yakir studied at the Higher Military Academy in Berlin. This was possible because of the intensive military cooperation between the Soviet Union and Germany. Yakir's innovative approaches to the military art impressed his German colleagues. German Field Marshal of World War I fame, Paul von Hindenburg, praised him as one of the most-talented military commanders of the post-World War I era. Upon repeated requests from German officers, Yakir gave special lectures on the Russian Civil War.  After returning to his district, Yakir continued military reform. He was one of the creators of the first large tank and air force formations in the world. Not a military theorist in his own right, Yakir strongly supported Tukhachevsky's endeavor in developing the theory of deep operations. Military historians across the world still consider this theory an outstanding theoretical innovation. In 1934 Yakir requested that Tukhachevsky would be appointed to conduct advanced courses on operational theory for high-ranking officers of the Red Army General Staff and commanders of military districts. He did it even though he knew about Joseph Stalin's dislike of Tukhachevsky. In retribution, Stalin instructed Kliment Voroshilov, the Peoples Commissar of Defense, to bar Yakir from membership in the prestigious Advisory Council of the Defense Commissariat. In 1935, in order to diminish Yakir's power, the Ukrainian Military District was divided into two new districts: Kiev, under Yakir's command, and Kharkov.  In September 1935, Yakir conducted major military maneuvers in Kiev, with the Kiev and Kharkov Military Districts' forces. The event resulted in several cover page articles in the Defense Comissariat's official journal, "Krasnaya Zvezda" (Red Star). The major aim of these maneuvers was to test the theory of deep operations and the latest technology. A total of 65,000 troops, including 1,888 paratroopers, 1,200 tanks and 600 aircraft participated in these maneuvers. These were first maneuvers in the world that used combined operations of large tank, air force and airborne formations. The troops acted along a front of and a depth of. The representatives of major world armies attended the maneuvers. French general Lucien Loizeau made very favorable comments about the technical and moral readiness of the Red Army. The German Wehrmacht copied Soviet innovations in preparation for World War II. The reform started by Frunze, and continued by Yakir, Tukhachevsky and many other commanders, made the Red Army into one of the most advanced armies in the world. During these years, Yakir regularly gave lectures to the Red Army General Staff Academy, informing the students about the newest developments in military affairs; his students considered him both an excellent speaker and tutor. In 1935 he was promoted to Komandarm 1st rank, the second-highest military rank in the Soviet Union at the time.

Political involvements.

Stalin, who was consolidating his power over the country, approved Yakir's appointment to the Ukrainian Military District in 1925. However, he did not trust him fully and instructed his political ally Lazar Kaganovich to become friends with Yakir and to report about his activities. Yakir, who was a firm believer in the Communist cause, was actively involved in internal politics. He was member of the party Central Committee in Moscow and member of the Politburo of the Communist Party of Ukraine. While ingenious and independent in his thinking as a military commander, in Soviet politics he was a docile party member and followed the Stalinist line. As a party member, he lacked the power of conviction and independent thinking to defy Stalin.  His blind obedience did not spare him. Stalin would not allow to his military commanders any independent thinking – he was paranoid of a coup plot. While Stalin's attitude toward Yakir was apparently friendly, the leader could not tolerate him. Starting with the Great Purge in 1936, the NKVD arrested many close associates and subordinates of Yakir. (This method became an NKVD routine in the course of the purges: this way they were able to create a professional and private vacuum around the target person.) Yakir was one of few top Soviet commanders who appealed to Stalin, even travelled to Moscow and tried to convince Voroshilov in person, claiming the innocence of these officers. However, Yakir's appeals (and his other reactions) were a clear sign of his disagreement with the ongoing purges which alienated Stalin even more.

Arrest, trial and death.

On 10 and 11 May 1937, the Red Army was shaken up by several major personal changes. Marshal Tukhachevsky was discharged from his position as a deputy commissar and was sent to command the Volga Military District which had little military importance. At the same time Yakir was also sent to a different post: from Kiev to Leningrad. Unlike Tukhachevsky, it wasn't an obvious demotion. Tukhachevsky was arrested on the way to his new post on 22 May. Yakir attended a conference in the Kiev Military District when he heard the news. His mood changed dramatically afterwards – normally he was cheerful, friendly, making jokes. This shift was attributed to his transfer to Leningrad.  On 31 May 1937, the NKVD arrested Yakir, and transported him to the Lubyanka prison in Moscow. He and seven other major military commanders (Robert Eideman, Boris Feldman, Avgust Kork, Vitaly Primakov, Vitovt Putna, Mikhail Tukhachevsky and Ieronim Uborevich) were accused of being members of the alleged Trotskyist Anti-Soviet Military Organization and of being Nazi agents. Except for Feldman, who was cooperative, all of them got brutally tortured. Yakir (until they broke him) maintained his innocence, both in correspondence to Joseph Stalin and at his trial on 11 July. Although he generally admitted taking part in a conspiracy, he denied being a spy. During the trial he was asked to provide further details about his written confession but he stated that he couldn't add anything more. One of his last letters to Stalin is really moving. Stalin and other members of the Politburo made a following cynical comments on this, creating a written conversation: "Rascal and prostitute" (Stalin). Kliment Voroshilov and Vyacheslav Molotov added: "A perfectly accurate definition". Lazar Kaganovich finally wrote: "The only punishment for the scoundrel, riffraff and whore is death penalty".  Yakir and the other seven commanders were executed in Moscow, virtually right after their trial at the dawn of 12 June 1937, without even reading their appeals. The man who performed their execution was Vasily Blokhin, the chief executioner of NKVD. The corpses were cremated on site, and the ashes were thrown into a mass grave dug at the Donskoye Cemetery. Members of the Yakir family were either immediately executed, like his younger brother, Moris Emmanuilovich (1902–1937), or sent to Gulag labor camps: Yakir's younger sister, Isabella Emmanuilovna (1900–1986) served there 10 years while his wife, Sarra Lazarevna (1900–1971) and his then-14-year-old son, Pyotr Ionovich (1923–1982), spent almost 20 years there. Yakir's military writings were banned. Plus, to morally finish the generals, newspapers dubbed them "treasonous", and published articles approving their execution, with the signatures of well-known Soviet artists – no matter if they in fact signed these articles or not (among those that refused was Boris Pasternak).

Legacy.

Opinions on Yakir are mixed, even today. As a young Civil War commander, he is thought to have used excessive force and violence (flamethrowers, machine guns) against civilian members of the resistance as well as the Cossack population, and was also involved in requisition. Later, during the years of agricultural collectivization, he launched what are alleged as punitive raids against starving peasants. It is the opinion of many that he was personally liable for the great famine in the Ukraine between 1932 and 1933. He also had other characteristics translated as vices by the puritan Stalin: Yakir never made a secret of his luxurious Kiev lifestyle (he lived in one of the palaces of the Mezhyhirya Residence), and he also lent dachas for profit and never ceased his involvement in trading.  But as a military reformer, Yakir was dedicated and remarkable. He worked on the improvement of the Red Army until his demise. On 10 June 1937, only 2 days before his execution, he wrote an extensive letter to Nikolay Yezhov, head of the NKVD, about his observations and the important duties in the field of military. After his death, Stalin's great purge wiped out large number of the officers who had served under him. Many of Yakir's achievements, including his reforms and preparations for guerrilla activities in the event of an invasion of Ukraine, were dismantled. When Germany invaded the Soviet Union in June 1941, the Red Army was largely incapable of modern warfare and unprepared to face an enemy who used military art which Yakir and other Soviet innovators were greatly familiar with. The Soviets suffered terrible defeats and huge human and territorial losses before remastering modern operational approaches and tactics. Yakir's disciples who survived the purge used the experiences which they had gained under Yakir to make a vital contribution to Soviet victory over Germany. Among them were Chief of the General Staff of the Red Army Aleksei Antonov, Front commanders Andrei Yeremenko and Ivan Chernyakhovsky, and Army commander Alexander Gorbatov.  During Nikita Khrushchev's de-Stalinisation, Yakir was rehabilitated on January 31, 1957. His cenotaph is in the Vvedenskoye Cemetery in Moscow.

Iona Emmanuilovich Yakir (; August 3, 1896 – June 12, 1937) was a Red Army commander and one of the world's major military reformers between World War I and World War II. He was an early and major military victim of the Great Purge, alongside Mikhail Tukhachevsky.

Jona Emanuilovič Jakir (rusky: "Иона Эммануилович Якир"; 3. srpna 1896, Kišiněv, dnešní Moldavsko – 11. června 1937, Moskva, Sovětské Rusko) byl komunistický politik, sovětský vojenský velitel a vojenský teoretik, armádní velitel I.třídy a náčelník Kyjevského vojenského okruhu.


Heat transfer principle.

A heat sink transfers thermal energy from a higher temperature device to a lower temperature fluid medium. The fluid medium is frequently air, but can also be water, refrigerants or oil. If the fluid medium is water, the heat sink is frequently called a cold plate. In thermodynamics a heat sink is a heat reservoir that can absorb an arbitrary amount of heat without significantly changing temperature. Practical heat sinks for electronic devices must have a temperature higher than the surroundings to transfer heat by convection, radiation, and conduction. The power supplies of electronics are not 100% efficient, so extra heat is produced that may be detrimental to the function of the device. As such, a heat sink is included in the design to disperse heat.  To understand the principle of a heat sink, consider Fourier's law of heat conduction. Fourier's law of heat conduction, simplified to a one-dimensional form in the "x"-direction, shows that when there is a temperature gradient in a body, heat will be transferred from the higher temperature region to the lower temperature region. The rate at which heat is transferred by conduction, formula_1, is proportional to the product of the temperature gradient and the cross-sectional area through which heat is transferred.  Consider a heat sink in a duct, where air flows through the duct. It is assumed that the heat sink base is higher in temperature than the air. Applying the conservation of energy, for steady-state conditions, and Newton’s law of cooling to the temperature nodes shown in the diagram gives the following set of equations:  where  Using the mean air temperature is an assumption that is valid for relatively short heat sinks. When compact heat exchangers are calculated, the logarithmic mean air temperature is used. formula_6 is the air mass flow rate in kg/s.  The above equations show that  Natural convection requires free flow of air over the heat sink. If fins are not aligned vertically, or if fins are too close together to allow sufficient air flow between them, the efficiency of the heat sink will decline.

Design factors.

Thermal resistance.

For semiconductor devices used in a variety of consumer and industrial electronics, the idea of "thermal resistance" simplifies the selection of heat sinks. The heat flow between the semiconductor die and ambient air is modeled as a series of resistances to heat flow; there is a resistance from the die to the device case, from the case to the heat sink, and from the heat sink to the ambient air. The sum of these resistances is the total thermal resistance from the die to the ambient air. Thermal resistance is defined as temperature rise per unit of power, analogous to electrical resistance, and is expressed in units of degrees Celsius per watt (°C/W). If the device dissipation in watts is known, and the total thermal resistance is calculated, the temperature rise of the die over the ambient air can be calculated.  The idea of thermal resistance of a semiconductor heat sink is an approximation. It does not take into account non-uniform distribution of heat over a device or heat sink. It only models a system in thermal equilibrium, and does not take into account the change in temperatures with time. Nor does it reflect the non-linearity of radiation and convection with respect to temperature rise. However, manufacturers tabulate typical values of thermal resistance for heat sinks and semiconductor devices, which allows selection of commercially manufactured heat sinks to be simplified.  Commercial extruded aluminium heat sinks have a thermal resistance (heat sink to ambient air) ranging from for a large sink meant for TO-3 devices, up to as high as for a clip-on heat sink for a TO-92 small plastic case. The popular 2N3055 power transistor in a TO3 case has an internal thermal resistance from junction to case of. The contact between the device case and heat sink may have a thermal resistance of between, depending on the case size, and use of grease or insulating mica washer.

Material.

The most common heat sink materials are aluminium alloys. Aluminium alloy 1050 has one of the higher thermal conductivity values at 229 W/m•K but is mechanically soft. Aluminium alloys 6060 (low stress), 6061, and 6063 are commonly used, with thermal conductivity values of 166 and 201 W/m•K, respectively. The values depend on the temper of the alloy. One-piece aluminium heat sinks can be made by extrusion, casting, or milling.  Copper has excellent heat sink properties in terms of its thermal conductivity, corrosion resistance, biofouling resistance, and antimicrobial resistance "(See also Copper in heat exchangers)". Copper has around twice the thermal conductivity of aluminium, around 400 W/m•K for pure copper. Its main applications are in industrial facilities, power plants, solar thermal water systems, HVAC systems, gas water heaters, forced air heating and cooling systems, geothermal heating and cooling, and electronic systems.  Copper is three times as dense and more expensive than aluminium. One-piece copper heat sinks can be made by skiving or milled. Sheet-metal fins can be soldered onto a rectangular copper body. Copper is less ductile than aluminium, so it cannot be extruded into heat sinks.

Fin efficiency.

Fin efficiency is one of the parameters which makes a higher thermal conductivity material important. A fin of a heat sink may be considered to be a flat plate with heat flowing in one end and being dissipated into the surrounding fluid as it travels to the other. As heat flows through the fin, the combination of the thermal resistance of the heat sink impeding the flow and the heat lost due to convection, the temperature of the fin and, therefore, the heat transfer to the fluid, will decrease from the base to the end of the fin. Fin efficiency is defined as the actual heat transferred by the fin, divided by the heat transfer were the fin to be isothermal (hypothetically the fin having infinite thermal conductivity). Equations 6 and 7 are applicable for straight fins:  Where: Fin efficiency is increased by decreasing the fin aspect ratio (making them thicker or shorter), or by using more conductive material (copper instead of aluminium, for example).

Spreading resistance.

Another parameter that concerns the thermal conductivity of the heat sink material is spreading resistance. Spreading resistance occurs when thermal energy is transferred from a small area to a larger area in a substance with finite thermal conductivity. In a heat sink, this means that heat does not distribute uniformly through the heat sink base. The spreading resistance phenomenon is shown by how the heat travels from the heat source location and causes a large temperature gradient between the heat source and the edges of the heat sink. This means that some fins are at a lower temperature than if the heat source were uniform across the base of the heat sink. This nonuniformity increases the heat sink's effective thermal resistance.  To decrease the spreading resistance in the base of a heat sink:

Fin arrangements.

A pin fin heat sink is a heat sink that has pins that extend from its base. The pins can be cylindrical, elliptical or square. A pin is one of the more common heat sink types available on the market. A second type of heat sink fin arrangement is the straight fin. These run the entire length of the heat sink. A variation on the straight fin heat sink is a cross cut heat sink. A straight fin heat sink is cut at regular intervals.  In general, the more surface area a heat sink has, the better it works. However, this is not always true. The concept of a pin fin heat sink is to try to pack as much surface area into a given volume as possible. As well, it works well in any orientation. Kordyban has compared the performance of a pin fin and a straight fin heat sink of similar dimensions. Although the pin fin has 194 cm surface area while the straight fin has 58 cm, the temperature difference between the heat sink base and the ambient air for the pin fin is. For the straight fin it was 44 °C or 6 °C better than the pin fin. Pin fin heat sink performance is significantly better than straight fins when used in their intended application where the fluid flows axially along the pins (see ) rather than only tangentially across the pins.  Another configuration is the flared fin heat sink; its fins are not parallel to each other, as shown in figure 5. Flaring the fins decreases flow resistance and makes more air go through the heat sink fin channel; otherwise, more air would bypass the fins. Slanting them keeps the overall dimensions the same, but offers longer fins. Forghan, et al. have published data on tests conducted on pin fin, straight fin and flared fin heat sinks. They found that for low approach air velocity, typically around 1 m/s, the thermal performance is at least 20% better than straight fin heat sinks. Lasance and Eggink also found that for the bypass configurations that they tested, the flared heat sink performed better than the other heat sinks tested.

Cavities (inverted fins).

Cavities (inverted fins) embedded in a heat source are the regions formed between adjacent fins that stand for the essential promoters of nucleate boiling or condensation. These cavities are usually utilized to extract heat from a variety of heat generating bodies to a heat sink.

Conductive thick plate between the heat source and the heat sink.

Placing a conductive thick plate as a heat transfer interface between a heat source and a cold flowing fluid (or any other heat sink) may improve the cooling performance. In such arrangement, the heat source is cooled under the thick plate instead of being cooled in direct contact with the cooling fluid. It is shown that the thick plate can significantly improve the heat transfer between the heat source and the cooling fluid by way of conducting the heat current in an optimal manner. The two most attractive advantages of this method are that no additional pumping power and no extra heat transfer surface area, that is quite different from fins (extended surfaces).

Surface color.

The heat transfer from the heat sink occurs by convection of the surrounding air, conduction through the air, and radiation.  Heat transfer by radiation is a function of both the heat sink temperature, and the temperature of the surroundings that the heat sink is optically coupled with. When both of these temperatures are on the order of 0 °C to 100 °C, the contribution of radiation compared to convection is generally small, and this factor is often neglected. In this case, finned heat sinks operating in either natural-convection or forced-flow will not be affected significantly by surface emissivity.  In situations where convection is low, such as a flat non-finned panel with low airflow, radiative cooling can be a significant factor. Here the surface properties may be an important design factor. Matte-black surfaces will radiate much more efficiently than shiny bare metal. A shiny metal surface has low emissivity. The emissivity of a material is tremendously frequency dependent, and is related to absorptivity (of which shiny metal surfaces have very little). For most materials, the emissivity in the visible spectrum is similar to the emissivity in the infrared spectrum; however there are exceptions, notably certain metal oxides that are used as "selective surfaces".  In a vacuum or in outer space, there is no convective heat transfer, thus in these environments, radiation is the only factor governing heat flow between the heat sink and the environment. For a satellite in space, a 100 °C (373 Kelvin) surface facing the Sun will absorb a lot of radiant heat, because the Sun's surface temperature is nearly 6000 Kelvin, whereas the same surface facing deep-space will radiate a lot of heat, since deep-space has an effective temperature of only a few Kelvin.

Engineering applications.

Microprocessor cooling.

Heat dissipation is an unavoidable by-product of electronic devices and circuits. In general, the temperature of the device or component will depend on the thermal resistance from the component to the environment, and the heat dissipated by the component. To ensure that the component does not overheat, a thermal engineer seeks to find an efficient heat transfer path from the device to the environment. The heat transfer path may be from the component to a printed circuit board (PCB), to a heat sink, to air flow provided by a fan, but in all instances, eventually to the environment.  Two additional design factors also influence the thermal/mechanical performance of the thermal design:

Attachment methods.

As power dissipation of components increases and component package size decreases, thermal engineers must innovate to ensure components won't overheat. Devices that run cooler last longer. A heat sink design must fulfill both its thermal as well as its mechanical requirements. Concerning the latter, the component must remain in thermal contact with its heat sink with reasonable shock and vibration. The heat sink could be the copper foil of a circuit board, or a separate heat sink mounted onto the component or circuit board. Attachment methods include thermally conductive tape or epoxy, wire-form z clips, flat spring clips, standoff spacers, and push pins with ends that expand after installing.  Thermally conductive tape is one of the most cost-effective heat sink attachment materials. It is suitable for low-mass heat sinks and for components with low power dissipation. It consists of a thermally conductive carrier material with a pressure-sensitive adhesive on each side.  This tape is applied to the base of the heat sink, which is then attached to the component. Following are factors that influence the performance of thermal tape:  Epoxy is more expensive than tape, but provides a greater mechanical bond between the heat sink and component, as well as improved thermal conductivity. The epoxy chosen must be formulated for this purpose. Most epoxies are two-part liquid formulations that must be thoroughly mixed before being applied to the heat sink, and before the heat sink is placed on the component. The epoxy is then cured for a specified time, which can vary from 2 hours to 48 hours. Faster cure time can be achieved at higher temperatures. The surfaces to which the epoxy is applied must be clean and free of any residue.  The epoxy bond between the heat sink and component is semi-permanent/permanent. This makes re-work very difficult and at times impossible. The most typical damage caused by rework is the separation of the component die heat spreader from its package. More expensive than tape and epoxy, wire form z-clips attach heat sinks mechanically. To use the z-clips, the printed circuit board must have anchors. Anchors can be either soldered onto the board, or pushed through. Either type requires holes to be designed into the board. The use of RoHS solder must be allowed for because such solder is mechanically weaker than traditional Pb/Sn solder.  To assemble with a z-clip, attach one side of it to one of the anchors. Deflect the spring until the other side of the clip can be placed in the other anchor. The deflection develops a spring load on the component, which maintains very good contact. In addition to the mechanical attachment that the z-clip provides, it also permits using higher-performance thermal interface materials, such as phase change types. Available for processors and ball grid array (BGA) components, clips allow the attachment of a BGA heat sink directly to the component. The clips make use of the gap created by the ball grid array (BGA) between the component underside and PCB top surface. The clips therefore require no holes in the PCB. They also allow for easy rework of components. For larger heat sinks and higher preloads, push pins with compression springs are very effective. The push pins, typically made of brass or plastic, have a flexible barb at the end that engages with a hole in the PCB; once installed, the barb retains the pin. The compression spring holds the assembly together and maintains contact between the heat sink and component. Care is needed in selection of push pin size. Too great an insertion force can result in the die cracking and consequent component failure.  For very large heat sinks, there is no substitute for the threaded standoff and compression spring attachment method. A threaded standoff is essentially a hollow metal tube with internal threads. One end is secured with a screw through a hole in the PCB. The other end accepts a screw which compresses the spring, completing the assembly. A typical heat sink assembly uses two to four standoffs, which tends to make this the most costly heat sink attachment design. Another disadvantage is the need for holes in the PCB.

Thermal interface materials.

Thermal contact resistance occurs due to the voids created by surface roughness effects, defects and misalignment of the interface. The voids present in the interface are filled with air. Heat transfer is therefore due to conduction across the actual contact area and to conduction (or natural convection) and radiation across the gaps. If the contact area is small, as it is for rough surfaces, the major contribution to the resistance is made by the gaps. To decrease the thermal contact resistance, the surface roughness can be decreased while the interface pressure is increased. However, these improving methods are not always practical or possible for electronic equipment. Thermal interface materials (TIM) are a common way to overcome these limitations.  Properly applied thermal interface materials displace the air that is present in the gaps between the two objects with a material that has a much-higher thermal conductivity. Air has a thermal conductivity of 0.022 W/m•K while TIMs have conductivities of 0.3 W/m•K and higher.  When selecting a TIM, care must be taken with the values supplied by the manufacturer. Most manufacturers give a value for the thermal conductivity of a material. However, the thermal conductivity does not take into account the interface resistances. Therefore, if a TIM has a high thermal conductivity, it does not necessarily mean that the interface resistance will be low.  Selection of a TIM is based on three parameters: the interface gap which the TIM must fill, the contact pressure, and the electrical resistivity of the TIM. The contact pressure is the pressure applied to the interface between the two materials. The selection does not include the cost of the material. Electrical resistivity may be important depending upon electrical design details.

Light-emitting diode lamps.

Light-emitting diode (LED) performance and lifetime are strong functions of their temperature. Effective cooling is therefore essential. A case study of a LED based downlighter shows an example of the calculations done in order to calculate the required heat sink necessary for the effective cooling of lighting system. The article also shows that in order to get confidence in the results, multiple independent solutions are required that give similar results. Specifically, results of the experimental, numerical and theoretical methods should all be within 10% of each other to give high confidence in the results.

In soldering.

Temporary heat sinks are sometimes used while soldering circuit boards, preventing excessive heat from damaging sensitive nearby electronics. In the simplest case, this means partially gripping a component using a heavy metal crocodile clip, hemostat, or similar clamp. Modern semiconductor devices, which are designed to be assembled by reflow soldering, can usually tolerate soldering temperatures without damage. On the other hand, electrical components such as magnetic reed switches can malfunction if exposed to hotter soldering irons, so this practice is still very much in use.

Methods to determine performance.

In general, a heat sink performance is a function of material thermal conductivity, dimensions, fin type, heat transfer coefficient, air flow rate, and duct size. To determine the thermal performance of a heat sink, a theoretical model can be made. Alternatively, the thermal performance can be measured experimentally. Due to the complex nature of the highly 3D flow in present applications, numerical methods or computational fluid dynamics (CFD) can also be used. This section will discuss the aforementioned methods for the determination of the heat sink thermal performance.

A heat transfer theoretical model.

One of the methods to determine the performance of a heat sink is to use heat transfer and fluid dynamics theory. One such method has been published by Jeggels, et al., though this work is limited to ducted flow. Ducted flow is where the air is forced to flow through a channel which fits tightly over the heat sink. This makes sure that all the air goes through the channels formed by the fins of the heat sink. When the air flow is not ducted, a certain percentage of air flow will bypass the heat sink. Flow bypass was found to increase with increasing fin density and clearance, while remaining relatively insensitive to inlet duct velocity.  The heat sink thermal resistance model consists of two resistances, namely the resistance in the heat sink base, formula_9, and the resistance in the fins, formula_10. The heat sink base thermal resistance, formula_9, can be written as follows if the source is a uniformly applied the heat sink base. If it is not, then the base resistance is primarily spreading resistance:  where formula_13 is the heat sink base thickness, formula_14 is the heat sink material thermal conductivity and formula_15 is the area of the heat sink base.  The thermal resistance from the base of the fins to the air, formula_10, can be calculated by the following formulas:  The flow rate can be determined by the intersection of the heat sink system curve and the fan curve. The heat sink system curve can be calculated by the flow resistance of the channels and inlet and outlet losses as done in standard fluid mechanics text books, such as Potter, et al. and White.  Once the heat sink base and fin resistances are known, then the heat sink thermal resistance, formula_26 can be calculated as:  Using the equations 5 to 13 and the dimensional data in, the thermal resistance for the fins was calculated for various air flow rates. The data for the thermal resistance and heat transfer coefficient are shown in the diagram, which shows that for an increasing air flow rate, the thermal resistance of the heat sink decreases.

Experimental methods.

Experimental tests are one of the more popular ways to determine the heat sink thermal performance. In order to determine the heat sink thermal resistance, the flow rate, input power, inlet air temperature and heat sink base temperature need to be known. Vendor-supplied data is commonly provided for ducted test results. However, the results are optimistic and can give misleading data when heat sinks are used in an unducted application. More details on heat sink testing methods and common oversights can be found in Azar, et al.

Numerical methods.

In industry, thermal analyses are often ignored in the design process or performed too late — when design changes are limited and become too costly. Of the three methods mentioned in this article, theoretical and numerical methods can be used to determine an estimate of the heat sink or component temperatures of products before a physical model has been made. A theoretical model is normally used as a first order estimate. Online heat sink calculators can provide a reasonable estimate of forced and natural convection heat sink performance based on a combination of theoretical and empirically derived correlations. Numerical methods or computational fluid dynamics (CFD) provide a qualitative (and sometimes even quantitative) prediction of fluid flows. What this means is that it will give a visual or post-processed result of a simulation, like the images in figures 16 and 17, and the CFD animations in figure 18 and 19, but the quantitative or absolute accuracy of the result is sensitive to the inclusion and accuracy of the appropriate parameters.  CFD can give an insight into flow patterns that are difficult, expensive or impossible to study using experimental methods. Experiments can give a quantitative description of flow phenomena using measurements for one quantity at a time, at a limited number of points and time instances. If a full-scale model is not available or not practical, scale models or dummy models can be used. The experiments can have a limited range of problems and operating conditions. Simulations can give a prediction of flow phenomena using CFD software for all desired quantities, with high resolution in space and time and virtually any problem and realistic operating conditions. However, if critical, the results may need to be validated.

A heat sink (also commonly spelled heatsink) is a passive heat exchanger that transfers the heat generated by an electronic or a mechanical device to a fluid medium, often air or a liquid coolant, where it is dissipated away from the device, thereby allowing regulation of the device's temperature. In computers, heat sinks are used to cool CPUs, GPUs, and some chipsets and RAM modules. Heat sinks are used with high-power semiconductor devices such as power transistors and optoelectronics such as lasers and light emitting diodes (LEDs), where the heat dissipation ability of the component itself is insufficient to moderate its temperature.

Chladič (též "chladník, refrigerátor") je technické zařízení, které je konstruováno jako specializovaný tepelný výměník pro výměnu tepla, ve kterém je teplo předáváno přímo nebo nepřímo z látky, která je v chladiči chlazená, do látky, která je chladičem ohřívána (princip zachování energie).


Hazardous eruption of 1982.

The last major eruption on Galunggung was in 1982, which had a Volcanic Explosivity Index of 4 and indirectly killed 18 people in traffic accidents and by starvation. This eruption also brought the dangers of volcanic ash to aviation to worldwide attention, after two Boeing 747 passenger jets flying downwind of the eruption suffered temporary engine failures and damage to exterior surfaces, both planes being forced to make emergency landings at Jakarta airport.  One plane, a British Airways aircraft traveling from Kuala Lumpur, Malaysia to Perth, Australia carrying 240 passengers, accidentally entered the ash cloud during night in June 1982 downwind of the volcano. All four engines failed due to the buildup of volcanic ash, and the aircraft descended for 16 minutes, losing of its altitude, until the crew managed to restart the engines and land in Jakarta.  The following month, a Singapore Airlines aeroplane with approximately 230 passengers aboard also inadvertently entered the cloud at night, and three of its four engines stopped. The crew succeeded in restarting one of the engines after descending. Both aircraft suffered serious damage to their engines and exterior surfaces.

Historical avalanche deposits.

A hummocky deposit known as the Ten Thousand Hills of Tasikmalaya attracted the attention of early-20th-century geologists. Houses were built on the hummocks since they provided good defence against hostile people, and being above the paddy fields were free of mosquitoes and rats.Originally, it was thought that either it had been formed by a lahar caused by the release of the waters of the crater lake, or that it was man-made, composed of rocks and boulders dumped there after being cleared from paddy fields.  However, in the light of the Mount St. Helens eruption of 1980 and from examination of the Mount Shasta deposits, it has become clear that the hummocks are a debris-avalanche deposit. Like these mountains, Galunggung has a horseshoe-shaped crater indicating a massive landslide, and examination of shattered lava blocks revealed them to be similar to deposits on the other two volcanoes. According to radiocarbon dating of samples taken from a lava flow, the landslide happened within the last 23,000 years.

Mount Galunggung (Indonesian: "Gunung Galunggung", formerly spelled "Galoen-gong") is an active stratovolcano in West Java, Indonesia, around southeast of the West Java provincial capital, Bandung (or around to the east of the West Java town of Tasikmalaya). Mount Galunggung is part of the Sunda Arc extending through Sumatra, Java and Bali, which has resulted from the subduction of the Australian plate beneath the Eurasian plate. Galunggung had its first historical eruption in 1500 that produced pyroclastic flows and lahars that killed 4,011 people.

Galunggung je aktivní stratovulkán v Západní Jávě v Indonésii, vysoký 2168 m n. m. Leží asi 40 kilometrů východoseverovýchodně od města Papandayan a 16 kilometrů severozápadně od města Tasikmalaya, pro jehož více než 700 000 obyvatel představuje přímé ohrožení.


Personal life.

Papis was born on October 3, 1969 in Como, Italy. He was raised in Italy and got an interest in car racing at a young age, winning several go-kart races and several rounds for racing clubs in Italy.  He is married to Tatiana Papis, daughter of the racing driver Emerson Fittipaldi, and has two children, Marco Papis and Matteo Papis. cousins of Pietro Fittipaldi and Enzo Fittipaldi. His sons' godfathers are fellow Italian Alex Zanardi (Marco) and British Dario Franchitti (Matteo).

Formula One.

After a spell as the Lotus team's test driver in, Papis replaced Gianni Morbidelli in the Footwork team for seven races in the middle of the 1995 Formula One season, as he brought valuable sponsorship to the cash-strapped outfit. Despite being a race-winner in Formula 3000, he often struggled with the unfamiliar car, and was occasionally outpaced by his much-maligned teammate, Taki Inoue. He also proved to be an unlucky driver, suffering a spectacular puncture and suspension failure on his début race at Silverstone due to clipping the pit lane wall after a tire change, being left on the grid at Hockenheim due to a transmission failure, and spinning on dust and oil kicked up by David Coulthard at the Ascari Chicane on the first lap of the Italian GP, causing a pile-up and a restart. However, he only missed out on a point in the restarted race when he was overtaken by Jean-Christophe Boullion's Sauber on the last lap. When Morbidelli returned, Papis was out of a drive and headed to America for 1996.

Champ Car.

He moved to CART Champ Car racing in 1996 as a replacement for Jeff Krosnoff, who was killed in the previous race in Toronto. In 1999, he joined the more competitive Rahal team, almost winning the US 500 before running out of fuel, and finishing fifth in the series. He started the next year by winning the 2000 season-opener, but failed to finish in the championship Top 10. In 2001, he won twice and finished sixth overall, but was dropped by the team, mainly due to two collisions with teammate Kenny Bräck. In 2002, he competed with Sigma Autosport, scoring two third places finishes at Long Beach and Milwaukee, before the team folded due to financial problems. The Italian did a partial season with PK Racing in 2003, with a best result of fourth at Road America. Papis also raced in the 2002 and 2006 Indianapolis 500s for Cheever Racing, claiming a 14th-place finish in his second appearance. He mostly concentrated on sportscars since 2001, remarking that "Champ Car needs me more than I need it" as the series struggled to fill its grid for 2003 after many teams defected to the IRL.

IndyCar.

Papis raced in the IRL early in his career. He has raced for Roger Penske, Andretti-Green Racing and Panther Racing from 2001 to 2009. Papis is a long-time friend of drivers Tony Kanaan and Alex Zanardi. In 2013 at the Indianapolis 500, Papis and Zanardi were present in the victory celebration when Kanaan won his first Indy 500.  In 2016, Papis was hired by the IndyCar Series as a race steward along with Arie Luyendyk and Dan Davis.

NASCAR.

He made his NASCAR debut in August 2006, competing in the Busch Series race at Watkins Glen International Raceway for McGill Motorsports following the release of Tim Sauter from the ride. He attempted to qualify for the NASCAR Cup Series race but failed to qualify.  Papis also announced that he would run 2 races in 2007 for James Finch's Phoenix Racing No. 01 Chevy. In his first race, at Montreal in the inaugural NAPA 200, Papis avoided Marcos Ambrose' crash (caused by a disqualified Robby Gordon), with 2 laps left, to finish in third place. At Watkins Glen the next week, his engine failed on lap 2.  Papis made his Cup Series debut at Infineon Raceway in 2008, piloting the No. 66 Haas CNC Racing Chevrolet in place of regular driver Scott Riggs. He was also scheduled to drive the No. 64 car for Rusty Wallace, Inc. on three road course races in the 2008 Nationwide Series. Haas CNC Racing hired Papis to drive the No. 70 Chevrolet Monte Carlo at the course at Watkins Glen in the Sprint Cup Series in August 2008. He was announced as the driver of the No. 13 GEICO Toyota in 18 races in the 2009 and a full-time ride in the 2010 Sprint Cup.  In his first Cup season with a dedicated ride, Papis recorded a career best 8th-place finish at Watkins Glen and 15th starting position at Fontana. He also recorded 12th-place finish at Infineon Raceway. In February at Daytona in 2010, Papis had the fastest truck in the truck series event, nearly winning his first Truck series event after leading for some laps. Papis was collected in an accident with 15 laps left in the race, while going towards the lead.  After Watkins Glen in 2010 the team announced that Papis would be replaced by Casey Mears for 2011 and Papis would race in the Truck Series for the team.  Also in 2010, Papis recorded a top-30 finish in the Daytona 500, but failed to qualify at Bristol. He nearly had a top ten running at Talladega but was caught up in an accident. At Montreal in the Nationwide Series, Papis drove for Richard Childress Racing and while leading on the final lap, took too much of a last-turn curb, got passed by Boris Said, and recorded a second-place finish.  In 2011, Papis raced in the Truck Series partly for KHI and Germain, resulting in an 18th-place finish in the standings.  From 2011 to 2013, Papis had good runs on the road-course races but did not win any of them. In 2011 at Road America he had a good car, but he was spun out by Jacques Villeneuve with two laps left. When the race ended, Papis blocked Villeneuve's car on pit road and they argued. In 2012, Papis finished in fourth-place at Road America. Also in 2012, Papis ran one race in NASCAR Canadian Tire Series at Kawartha Speedway driving No. 24 Dodge for Scott Steckly, he started 16th and finished 21st.  In 2013 at Road America, Papis, who spent nearly the entire race in the top five, found himself being spun out twice in the waning laps. When the race was over, a furious Papis went up to Billy Johnson (who spun him out one of the times) and slapped him. After being separated by officials Papis and Johnson exchanged shouts ending with Papis walking off. When he spoke to reporters, Papis apologized for the slap.  In early August 2013, Papis was named to substitute for Tony Stewart in the No. 14 Chevrolet in the Sprint Cup Series at Watkins Glen International after Stewart suffered a broken leg in a sprint car accident. He posted a solid top 15 finish. Papis also competed in the inaugural Nationwide Children's Hospital 200 at the Mid-Ohio Sports Car Course for Richard Childress Racing, finishing in fourth place.  Papis drove for NTS Motorsports in the Camping World Truck Series' inaugural race at Canadian Tire Motorsport Park, the 2013 Chevrolet Silverado 250, in September 2013. Finishing 6th in the event, he was slapped following the race by the girlfriend of driver Mike Skeen, who he had crashed with on the final lap, suffering a dislocated jaw.  Also in 2013, Papis ran 4 races in the NASCAR Whelen Euro Series Elite 1 Division, he ran two races driving No. 33 Chevrolet for OverDrive team and two races driving No. 19 Chevrolet for his own team (Max Papis Racing). Papis had a best finish of 2nd at Tours Speedway. In 2014, Papis' team fielded the No. 99 car for the NASCAR Whelen Euro Series for Kevin Gilardoni in the Elite 1 Division.  In 2017, Papis ran one race in NASCAR K&N Pro Series East driving No. 13 Toyota for Eric McClure at Watkins Glen International, he started 17th and finished 18th after blew the engine.

Other racing.

In 2016, Papis made his debut in Stadium Super Trucks series, running the Honda Indy Toronto rounds in the No. 9 truck. He finished eleventh and seventh.

"Mad Max".

Papis earned the nickname "Mad Max" at the 1996 24 Hours of Daytona during his last stint at the end of the race. Although his second-place Ferrari 333SP had been battered due to collisions, some of its bodywork held together by tape, Papis unlapped himself by passing the race leader (the Doyle Racing Riley & Scott-Oldsmobile driven by Wayne Taylor) and proceeded to set some of the fastest laps of the entire race. Taylor was nursing his car around the track due to an overheating problem and otherwise would have been able to cruise to a win, but Papis' pace and the slowing Oldsmobile suggested that Papis could theoretically take the win from him. Papis' speed was achieved at the cost of maximum fuel consumption and although he drove down the pit lane at full speed to re-fuel (pit lane speed limits were imposed the next year), Taylor was still ahead by 64 seconds at the end of the race.

Motorsports career results.

Complete International Formula 3000 results.

() (Races in bold indicate pole position) (Races in "italics" indicate fastest lap)

Massimiliano "Max" Papis (born October 3, 1969) is an Italian professional motorsport driver who has competed in several top-level motorsports events such as Le Mans 24 Hours, Formula One and Champ Car. He has three Champ Car victories. He is the son-in-law of Emerson Fittipaldi. Papis also currently drives in the NASCAR Whelen Euro Series.

Massimiliano "Max" Papis (3. října 1969, Como) je italský automobilový závodník. V současnosti závodí v NASCAR pro tým German Racing. V roce 1996 získal přezdívku „Mad Max“ („Šílený Max“) kvůli svému jezdeckému stylu.


Style.

Kolářová belongs to the generation which touched off an iconoclastic revolution and "rearmament" in Czech art during the 1960s. This new wave hit the scene with a program of objective tendencies, proclaiming that art can exist as a process, concept, method, experiment and language, or as something "concrete"—such as a found and designed object. Kolářová’s training is in photography, and her role in the 1960s reversal was associated with this medium from the beginning. As with many of her contemporaries, she arrived at the conclusion that it is not possible to photograph the world, i.e. to use classic methods of representing reality.  She therefore invented her own method and technology, the artificial negative. She pressed small objects into layers of paraffin on small pieces of cellophane, or she actually applied small fragments of natural and artificial materials. Instead of choosing the world that it is possible to photograph and represent as an exterior appearance, she chose the world that is possible to accept, to appropriate as an assemblage of material fragments, using light to transfer them into an autonomous picture on the sensitive surface of photographic paper.  Her path began in doubt. She doubted the meaning of photography, despite considering it her personal medium. Reflecting on this in 1968, she asked herself, "Was there really nothing left but to add the things we see to those already seen a hundred times over, to keep reshaping that which has long been discovered?" From this sense of distrust, she developed a form of experimental photography that was close to the principles of the 1920s movement New Vision. The artist stated, "Gradually I begun to perceive a world which, in fact, was left out unnoticed by photographers. A world so negligible and everyday as if past the merit of being photographed. Small things, indispendable for our life yet taken for granted so that we can hardly notice them in spite of their great number..." [Bèla Kolářová, 'One of the Ways,' in Bèla Kolářová. cat.Raven Row (London, 2013),10-14]  For some time, Kolárová worked without a camera. She arranged bits of paper, thread, or shards on transparent film, or pressing them like stamps, into a coat of paraffin. She then exposed these compositions and called them "artificial negatives." These were similar to the cliché verre process.  After this phase, she photographed regular objects: household objects, eggshells, crow caps. These systematic formations of ordinary objects initiated her next artistic phase, around 1964. She removed the mediating camera and turned to assemblage. Marie Klimešová notes, Kolářová took recourse here to the modernist or minimalist model of the grid. She did this deliberately to limit the role of the artist's "signature" in favor of a conceptualism that was still unusual.  She was inspired by the constructivist-geometrical program of the group Křižovatka that she was part of along with her husband and fellow artists Zdeněk Sýkora and. Kolárová was never devoted to purely rational, completely self-sufficient structure.  A tension filled geometry of intimacy emerged in the late 1970s. She started to use cosmetics to draw. She used lipstick, eyeshadow, eyeliner, and similar. While working this way she still remained faithful to the grid model while mixing it with a colorful symbolism of femininity.

Career.

Kolářová's work has been exhibited extensively since the 1960s. In 1966 the Gallery in Charles Square in Prague held her first solo exhibition. By the 1980 Kolářová's work included more assemblages. In 1994 she participated in the group exhibition "Europa, Europa. Das Jahrhundert der Avantgarde in Mittel- und Osteuropa" (Europe, Europe. The Century of the Avant-garde in Central and Eastern Europe) at the Kunst- und Ausstellungshalle der Bundesrepublik Deutschland in Bonn. Her work continues to be exhibited posthumously.  Her work is owned by the Moravian Gallery in Brno, the Musée National d'Art Moderne in Paris,the National Gallery in Prague, the Museum of Decorative Arts in Prague, and the Olomouc Museum of Art. In 2017 the Metropolitan Museum of Art acquired an early piece entitled "Letters From Portugal".

Běla Kolářová née Helclová (24 March 1923, in Terezín – 12 April 2010, in Prague) was a Czech artist and photographer. In 1949 she married Jiří Kolář (1914-2002). In 1985 she followed her husband in exile in Paris. They returned to Prague in 1999. She died in Prague on 12 April 2010.

Běla Kolářová, rozená Helclová (24. března 1923 v Terezíně – 12. dubna 2010 v Praze) byla česká fotografka a výtvarná umělkyně. Jako žena Jiřího Koláře zůstala pro veřejnost v jeho stínu a tvořila mu zázemí po dobu jejich společného života, Jiří a Běla Kolářovi ale dlouhá léta spolupracovali, vytvářeli i společná díla.


Writing and inspiration.

"Blah Blah Blah" was written by Kesha alongside Neon Hitch, Sean Foreman, and Benny Blanco, who also produced the song. Kesha said that the song originated from a discussion they had in the studio on the politics of female-male relationships which Kesha later explained, "The song came about when the people that wrote it — me, Benny Blanco, Neon Hitch and [3OH!3's] Sean Foreman — all got in a room, and they were talking about how chicks talk too much," [...] "And me and Neon were like, 'No, no, no, guys talk too much," [...] "So, we had this war of who were more obnoxious, chicks or dudes. And the song kind of came around from that conversation. I think I make a pretty fair point both in this video and in the song, that dudes are way more annoying."

Composition.

"Blah Blah Blah" is a midtempo electropop song; the song utilizes synthesizers and drum machines in its production. It is written in the key of D minor and Kesha's vocal range in the song spans from the note of D to the note of D. Lyrically, "Blah Blah Blah" depicts a woman who would rather have sex than listen to a man speak as the singer finds talkative men annoying; blatant come-ons such as "show me where your dick's at" and "I wanna be naked" leave this literal meaning unambiguous. Kesha herself has been frank about this straightforward interpretation of the lyrics. The lyrics have been interpreted as a shot at the way men objectify women by speaking about them the way that they do in the music industry. " Andrew Burgess of MusicOMH felt that the line "I don't really care where you live at, just turn around boy, let me hit that. Don't be a little bitch with your chit-chat; just show me where your dick's at" was a way of belittling her male peers. Fraser McAlpine of BBC noted that it was cultural progress that a woman can now "sing a song[...] as dirty [...] as her male peers".

Critical reception.

Fraser McAlpine of the BBC was impressed with the song saying "it's a sign of cultural progress that a modern pop lass can sing a song which is exactly as dirty as the kind of song her male peers would risk." He compared Kesha's vocal delivery to that of Eminem, he also compared the hook, "you tah-tah-tawkin' that Blah Blah Blah" to "Bad Romance" by Lady Gaga, stating that the song was a "rural, farm-girl spin" of it. Jim Farber of the New York "Daily News" stated that the track "could become the 'whatever' anthem of the season." It was described by the "Winnipeg Free Press" as a "hard pop-hop cut with pogo-worthy beats." Daniel Brockman of "The Phoenix" thought that Kesha "intone[d] in a lusty, disturbingly carefree tone" on the song.  Ann Powers of the "Los Angeles Times" said that "Blah Blah Blah" was one of those "moments on "Animal" that are nearly as experimental as an Animal Collective record, but instead of some wistful, Brian Wilson-loving artiste at the song's center, there's this girl, rolling her eyes and snapping her gum." Melanie Bertoldi from "Billboard" magazine also thought that the verse by 3OH!3 "severely slow[ed] down the momentum and never quite gel[ed] with Kesha's catty, aggressive delivery," but praised the song for its "danceability". Andrew Burgess of MusicOMH said that while "3OH!3 makes a lame attempt to assert the case for male equality [on the song], Kesha comes off as so infectiously dominating, it's hard to take [3OH!3] seriously." Mayer Nissim of Digital Spy gave the song two out of five stars, stating that it was not as catchy as her debut, slamming the lyrics for being "thick" and adding that she failed to deliver on many lines, calling them "faux-outrageous, faux-feminist trash". Melinda Newman of HitFix criticized the song, calling 3OH!3 "slumming" and "wretched."

Chart performance.

In the United States, "Blah Blah Blah" debuted on the "Billboard" Hot 100 at position seven, and on the Hot Digital Songs chart at number two, selling a total of 206,000 downloads, both chartings would become the songs' peaks. On "Billboard's" Pop chart, the song reached a peak of eleven. The song has received Platinum certification by the Recording Industry Association of America for sales of 1,000,000 units and as of February 2011, the song has sold I the United States more than two million digital copies. as of June 2011, the song has sold 2,132,000 copies in the United States. As of March 2016, "Blah Blah Blah" has sold 2.4 million digital copies. In Canada, "Blah Blah Blah" debuted on the Canadian Hot 100 at position three, which became its peak. In March 2010 the single was certified double platinum by the Canadian Recording Industry Association (CRIA) for sales of 160,000 units.  In Australia, "Blah Blah Blah" entered the Australian chart at position seven on the week of January 24, 2010. The following week the song moved to position four, where it held the spot for three consecutive weeks. On the song's fifth week on the chart, it reached its peak at position three where it held the spot for one week. The song was certified platinum by the Australian Recording Industry Association (ARIA) for sales of 70,000 units. In New Zealand, the song debuted and peaked at position seven. It later went on to receive gold certification by the Recording Industry Association of New Zealand (RIANZ) for sales of 7,500 units. "Blah Blah Blah" made its debut onto the UK Singles Chart at number eleven on the issue dated February 7, 2010 with sales of 27,161.

Music video.

The music video for the song was directed by Brendan Malloy. It premiered on February 23, 2010, on Vevo. Both members of 3OH!3 make an appearance in the video. Kesha told MTV that the video primarily involves men (described as "douchey") hitting on Kesha, while she declines their advances. "At one point," Kesha says "I get to be strapped to this harness and bouncing around everywhere, and it was really cool [...] The whole concept of the video was a bunch of douche-y guys macking on me as usual, and me making them eat their toupees or other various items". Melanie Bertoldi of "Billboard" said that the clip was "thoroughly entertaining".  In the first scene, outside of a club, Kesha is hit on by comedian Bret Ernst. He tries to convince Kesha that they would make a good couple, meanwhile Kesha texts someone, describing the man as a "major douchemaster". The next scene has Kesha at a bar playing pool near a man, where she duct-tapes him, later pulling down his pants, after describing him as a "tool bag" in a text message. In an arcade, Kesha pushes a man away who is making conversation with her. The third suitor attempts to serenade Kesha with a guitar, to which Kesha replies by stuffing paper in his mouth. In the final sequence, a man tries to talk to Kesha in a bowling alley. She loses interest when his toupée falls off his head and she shoves the hairpiece into his mouth, in vein of the previous arcade scene. The video ends with Kesha and 3OH!3 singing and dancing together in the bowling lanes.

Live performances.

The song was first performed live for "MTV Push", a program broadcast by MTV Networks worldwide. It was also performed on January 18, 2010, at "MuchOnDemand", broadcast on Canadian cable music channel, MuchMusic. Kesha performed for the first time a heavily censored version of the song on the ninth season of "American Idol" with 3OH!3 on March 17, 2010. In the United Kingdom, Kesha made two appearances to perform the song. The first was on February 18, 2010, "". It was followed by a performance on breakfast television show GMTV, on February 19. She also performed the song in a set for BBC Radio 1's Big Weekend, as well as "Willkommen Bei Mario Barth Live" in Germany and "So You Think You Can Dance" in Australia.

Credits and personnel.

Source

"Blah Blah Blah" is a song by American recording artist Kesha from her debut album, "Animal" (2010). Produced by Benny Blanco, and co-written by Kesha, Blanco, Neon Hitch and Sean Foreman, it was released as the album's second single on February 19, 2010, and features 3OH!3. Initial writing of the song took place when Kesha, Blanco, Hitch and Foreman were discussing which sex talked more and which one was more "obnoxious." The song is a midtempo electropop song that speaks of men in the same way that they have talked about women in the music industry. The lyrics depict a woman who would rather have sex than listen to a man speak and features blatant come-ons throughout the song.

„Blah Blah Blah“ je píseň americké popové zpěvačky Keshy. Píseň pochází z jejího debutového alba "Animal". Produkce se ujal producent Benny Blanco. S touto písní jí vypomohla americká elektro-hopová skupina 3OH!3.


Reign.

Edgar claimed the kingship in early 1095, following the murder of his half-brother Duncan II in late 1094 by Máel Petair of Mearns, a supporter of Edgar's uncle Donald III. His older brother Edmund sided with Donald, presumably in return for an appanage and acknowledgement as the heir of the aged and son-less Donald.  Edgar received limited support from William II of England as Duncan had before him; however, the English king was occupied with a revolt led by Robert de Mowbray, Earl of Northumbria, who appears to have had the support of Donald and Edmund. Rufus campaigned in northern England for much of 1095, and during this time Edgar gained control only of Lothian. A charter issued at Durham at this time names him "... son of Máel Coluim King of Scots... possessing the whole land of Lothian and the kingship of the Scots by the gift of my lord William, king of the English, and by paternal heritage."  Edgar's claims had the support of his brothers Alexander and David — Ethelred was Abbot of Dunkeld, and Edmund was divided from his siblings by his support of Donald — and his uncle Edgar Ætheling as these witnessed the charter at Durham.  William Rufus spent 1096 in Normandy which he bought from his brother Robert Curthose, and it was not until 1097 that Edgar received the further support which led to the defeat of Donald and Edmund in a hard-fought campaign led by Edgar Ætheling.  Although Geoffrey Gaimar claimed that Edgar owed feudal service to William Rufus, it is clear from Rufus's agreement to pay Edgar 40 or 60 shillings a day maintenance when in attendance at the English court that this was less than accurate. In any event, he did attend the court on occasion. On 29 May 1099, for example, Edgar served as sword-bearer at the great feast to inaugurate Westminster Hall. After William Rufus's death, however, Edgar ceased to appear at the English court. He was not present at the coronation of Henry I.  Edgar was certainly not heir by primogeniture, as later kings would be, since Duncan II had a legitimate son and heir in the person of William fitz Duncan. With Donald and Edmund removed, however, Edgar was uncontested king of Scots, and his reign incurred no major crisis. Compared with his rise to power, Edgar's reign is obscure. One notable act was his gift of a camel (or perhaps an elephant), presumably a'souvenir' of the First Crusade, to his fellow Gael Muircheartach Ua Briain, High King of Ireland.  In 1098, Edgar signed a treaty with Magnus Barefoot, King of Norway, setting the boundary between Scots and Norwegian claims in the west. By ceding claims to the Hebrides and Kintyre to Magnus, Edgar acknowledged the practical realities of the existing situation. Edgar's religious foundations included a priory at Coldingham in 1098, associated with the Convent of Durham. At Dunfermline Abbey he sought support from Anselm of Canterbury with his mother's foundation from which the monks of Canterbury may have been expelled by Domnall Bán.  Edgar died in Edinburgh on 8 January 1107 and was buried at Dunfermline Abbey. Unmarried and childless, he acknowledged his brother Alexander as his successor. Edgar's will also granted David an appanage in "Cumbria" (the lands of the former Kingdom of Strathclyde), and perhaps also in southern parts of Lothian. David would later be known as Prince of the Cumbrians

Contradictory account of his death.

There is a contradictory account of his death, recorded by Orderic Vitalis (12th century). According to this account, Edgar was killed by his uncle Donald III, while Donald III was killed by Alexander I. This account reports: "On the death of Malcolm [III], king of the Scots, great divisions rose among them, in reference to the succession to the crown. Edgar, the king's eldest son, assumed it as his lawful right, but Donald, King Malcolm's brother, having usurped authority, opposed him with great cruelty, and at length the brave youth [Edgar] was murdered by his uncle. Alexander [I], however, his brother, slew Donald, and ascended the throne; being thus the avenger as well as the successor of his brother...".  Benjamin Hudson dismisses the story as "completely false". But its existence points to the circulation of "incorrect" tales about the monarchs of the late 11th century. Verses of "The Prophecy of Berchán" allude to the murder of another Scottish king: "Alas a king will take sovereignty for four nights and one month;I think it is grievous that the Gaels will boast, woe to him who celebrates him.... A son of the woman of the English... I think it is wretched, that his brother will kill him." The English woman is obviously Saint Margaret, the Anglo-Saxon consort of Malcolm III. But none of her children, male or female, are known to have been killed by one of their own siblings. The confusion probably derives from the murder of their half-sibling Duncan II of Scotland, son of Malcolm III and his first wife Ingibiorg Finnsdottir. A note in the Annals of Ulster claims that Duncan II was murdered by his brothers Donmall [Donald] and Edmund. As Duncan had no brothers by these names, the text probably points to his uncle Donald III and half-brother Edmund of Scotland, though later texts identify a noble by the name of Máel Petair of Mearns as the actual murderer.

Edgar or Étgar mac Maíl Choluim (Modern Gaelic: "Eagar mac Mhaoil Chaluim"), nicknamed Probus, "the Valiant" (c. 1074 – 8 January 1107), was King of Scotland from 1097 to 1107. He was the fourth son of Malcolm III and Margaret of Wessex but the first to be considered eligible for the throne after the death of his father.

Edgar (cca 1074 – 8. leden 1107) byl král Skotska (Alby) v letech 1097 až 1107. Byl synem Malcolma III. a jeho první ženy Markéty.


History.

2000s.

The national broadcaster of Albania, Radio Televizioni Shqiptar (RTSH), made the country's debut at the 2004 contest in Istanbul with the song "The Image of You" performed by Anjeza Shahini. The country received 106 points in the grand final and finished in the seventh place remaining the country's highest placement until 2012. In 2005, due to the country's top 11 placement the previous year, the succeeding entry "Tomorrow I Go" by Ledina Çelo automatically qualified for the grand final and reached the sixteenth place in Kyiv. The following year, Luiz Ejlli and his entry "Zjarr e ftohtë" failed to qualify for the grand final in Athens simultaneously marking the first time in their participation history.  The 2007 entry was Frederik Ndoci with "Hear My Plea", performed at Festivali I Këngës 45 as "Balada e gurit" (The stone ballad). The song was performed at Eurovision in both English and Albanian. In the semi-final of the 2007 contest he received 49 points, placing 17th of 28 in his semi-final and failing to qualify for the final.  The winner of Festivali I Këngës 46 was "Zemrën e lamë peng" (Hearts trapped in time) by Olta Boka. However the result of the juries that selected the winner was controversial and rumours arose that the final two judges intentionally awarded high marks to Boka in order to avoid sending the runners-up, Flaka Krelani and Doruntina Disha, to the contest. Press reactions in Albania were not happy with the decision, and RTSH announced that they would investigate into alleged cheating by the final two judges to award their points. Despite this, Olta Boka's victory remained, and she sang for Albania at the Eurovision Song Contest 2008 in Belgrade, Serbia. She qualified for the final, coming 9th in a field of 19 in the second semi-final, and in the final she received 55 points, coming equal 17th in a field of 25.  Albania was the first country to select both their artist and publicly present their song for Eurovision 2009. The winner was again selected by Festivali I Këngës. The winner of Festivali I Këngës 47 was Kejsi Tola with the song "Më merr në ëndërr" (Take me in your dreams), which was composed by the composers of Albania's first entry Edmond Zhulali and Agim Doçi. The song was performed in English as "Carry Me in Your Dreams". Albania finished 7th out of 19 in the 2nd semifinal with 73 points, thus qualifying for the final. In the final, where both jury and televoting were used, Albania scored 48 points, finishing 17th in a field of 25. However, had only televoting been used Albania would have placed 11th in the contest. Conversely if only jury voting had been used Albania would have placed 23rd.

2010s.

The winner of Festivali I Këngës 48 was decided on 27 December, with Juliana Pasha winning over former winner Anjeza Shahini. She represented Albania at Eurovision 2010 in Oslo with the song "It's All about You". The song was a typical up-tempo composition, and has been compared to Christina Aguilera's "Keeps Gettin' Better" and Britney Spears' "Womanizer". Albania came 6th in the first semi-final with 76 points, thus qualifying for the final. In the final, Juliana finished 16th with 62 points which included 12 points from Macedonia.  The Albanian participant for the 2011 Eurovision Song Contest was chosen in Festivali i Këngës 49 in December 2010. The winner of 2011's Festival of Song was Aurela Gaçe, winning for the third time after 10 years. Her song was named ""Kënga ime"" ("My Song") and it was translated into English with the name "Feel the Passion", published in 12 March 2011, during a show called ""Historia nis këtu"" ("The story begins here") in RTSH. Albania participated in Semi-Final 1 against 18 other countries, fighting for a place in the grand final in 14 May. However they missed out on qualification for the final for the first time in 4 years, coming 14th.  Albania competed in the 2012 competition with the song "Suus", which was performed by Rona Nishliu. The song got through to the final, coming in 5th place overall with 146 points. Rona Nishliu from Kosovo achieved a record result for Albania.  Albania competed in the 2013 Eurovision Song Contest with the song "Identitet" which was performed by Adrian Lulgjuraj and Bledar Sejko. This song was chosen as the winner through the Festivali i Këngës. The results depended on the jury voting only. Among the experts in the jury was the Italian Head of Delegation at the Eurovision Song Contest, Nicola Caligiore, who greeted and gave the points in English for all the viewers from the Eurovision.tv webcast. Albania came 14th in the second semi-final of the 2013 Eurovision Song Contest in Malmö and did not make it into the grand final.  On 28 December 2013, Herciana Matmuja won Festivali i Këngës 52 (the 52nd national final of Albania) and was therefore chosen to represent Albania in Eurovision 2014 with her song 'Zemërimi i një nate'. In the time before Eurovision 2014 she recorded both English and Albanian versions of this song. On 16 March she released the final version of 'One Night's anger' for Eurovision 2014. Albania failed to qualify for the second year in a row.  On 28 December 2014, Elhaida Dani won Festivali i Këngës 53 with the song "Diell", and this represented Albania at the Eurovision Song Contest 2015. On 23 February 2015 it was announced that the songwriters had decided to withdraw the song and Dani would perform something else at Eurovision. The following day it was revealed that Dani would perform "I'm Alive".  On 27 December 2015 Eneda Tarifa won Festivali i Këngës 54 with her song "Përrallë" which meant she would represent Albania in the Eurovision Song Contest 2016. Albania was the first country to reveal both the artist and song together. It was later translated into English and called "Fairytale", and the music video premiered on the evening news on TVSH. Albania failed to qualify, coming only 16th out of 18 in the second semi-final.  After failing to qualify once again in 2017 with Lindita and the song "World", Albania returned to the grand final in 2018 with the song "Mall" by Eugent Bushpepa. It finished 11th of 26 in the final receiving 184 points, giving Albania its third best result in the contest since their debut. The song fared better with the juries, coming 7th in the final respectively.  In 2019, Albania selected Jonida Maliqi to represent them with the song "Ktheju tokës". Albania succeeded in qualifying from the second semi-final, making it the first time Albania had qualified twice in a row since 2009 and 2010.

Albania has participated in the Eurovision Song Contest 16 times since its debut in, and has placed in the top ten two times. Festivali i Këngës, a long-standing song contest that takes place every year in Albania since 1962, is used to select the country's entrant for that year's Eurovision Song Contest.

Albánský veřejnoprávní vysílatel projevil zájem o účast na Eurovizi již v roce 2003, kvůli pokynu EBU však debutovala až v roce 2004. Národním kolem albánské televize je každorodní hudební soutěž Festivali i Kënges.<br>Nejlepším výsledkem země je páté místo na Eurovizi 2012, které vybojovala zpěvačka Rona Nishliu s písní ""Suus"".