6531657
A new high gain low voltage 1.45 GHz CMOS mixer
A new architecture of CMOS downconversion mixer for low voltage and high gain communication applications is proposed. This topology avoids the stacking of transistors between the power and ground lines, thus it can work on a low supply voltage. It does not need inductors, so it is relatively easy to fabricate. This mixer is implemented using a 0.25 /spl mu/m CMOS technology with supply voltage of 2 V. With 1.452 GHz LO input and 1.45 GHz RF input, simulation result show that the conversion gain is 15 dB, IIP3 is -4.5 dBm, noise figure is 17 dB, the maximum transient power dissipation is 9.3 mW and DC power dissipation is 9.2 mW. The mixer's noise and linearity analyses are also presented.
10474493
Calculation of intermodulation distortion in CMOS transconductance stage
The linearity of the transconductance stage is of major concern in the design of some analog circuits. In this paper, Volterra series expansion is used to compute the intermodulation distortion of high frequency CMOS transconductance stage with source degeneration resistor. The MOS model used in this paper includes short-channel effects and gate-source capacitance, gate-drain capacitance, and output resistance of the MOS transistor. Analytical results are compared with simulation results and the influences of circuit parameters on circuit linearity are discussed.
6788128
Airport Internal Safety Risk Assessment using Fuzzy Hierarchy Process Approach
This paper offers an assessment of airport internal safety risk. It deals with general concept of risk and safety, describes the main causes of airport risk. A model based on fuzzy simulation technique and hierarchical structure analysis is developed to evaluate the airport internal safety risk. With the use of linguistic terms, subjective assessments of qualitative safety risk indexes are represented with fuzzy variable. The relative weights of safety attributes are assessed using a pairwise comparison process. Based on the concept of optimality, fuzzy simulation approach is employed to dispose of the evaluation model and compute the expected values. Then the shortcoming of the traditional analytic hierarchy process (AHP) is made up. Finally, an empirical study about a major domestic airport is conducted to demonstrate the effectiveness of the approach.
16303483
A Case Study of Enterprise Application Integration Based on Workflow Management System
Work flow management system (WFMS) is a flexible tool for enterprise application integration (EAI). The EAI implement with work flow technology is cheap and convenient. This enlarges the view of enterprises and gives them an opportunity to integrate their legacy applications by advanced IT technology. By study on environment and stratagem of enterprises, this paper establishes a solution of the EAI based on work flow management system and presents an EAI framework with an embedded workflow management component to support business-to-business operations. Nowadays, however, such system is not common. A case study of EAI implement in Tianjin Port is presented and a brief overview of the current enterprise applications and information systems in this enterprise are also presented.
3041039
The Impacts of Enterprise Resource Planning Systems on Firm Performance: An Empirical Analysis of Chinese Chemical Firms
Chinese firms heavily invest in enterprise resource planning systems (ERP) in recent years and expect that ERP can help them gain superior financial performance. Given the high costs and high risk of ERP investments, to quantify the financial benefits of ERP implementation is an important research issue. This paper empirically examines the impacts of ERP implementation on firm performance using the financial data from 50 Chinese chemical firms that implemented ERP. The firms’ abnormal performance during the two-year implementation period and three-year post-implementation period was analyzed based on the guideline of Barber et al. on event studies. The results find no significant performance improvement during the implementation period and the three-year post-implementation period and a decline in performance in the first two years after implementation. However, a slight performance improvement in the third year after implementation may indicate that the financial benefits of ERP may show after a long-term ERP use. These results provide insight for Chinese firms that want to invest in ERP.
5384230
A Simulation Platform for Intelligent Scheduling In Automated Container Terminal
The present invention relates generally to a method and apparatus for evaluating the resistivity of invaded formations at high apparent dip angle. A multi-array induction tool having a plurality of arrays is disposed in a borehole. Signals from a subset of coils of the array are selected to probe different volumes of the formation surrounding the borehole. The maximum entropy method is used to process data from the subset of coils to effectively remove distortions produced by shoulder and dip effect in the presence of shallow, moderate, or deep invasion. An advantage of the invention is a computer program that accurately predicts the response of induction arrays in an assumed layered formation with dip. After processing the data, the resulting multi-array induction log will indicate a conductivity profile for the subset of coils which is substantially identical to that of an array in a thick bed, without dip or layering, with the same invasion profile. A 1D radial inversion of the resulting logs at each point in depth will give a closer estimate of the actual formation parameters, Rxo, Rt, and the invasion radius.
17479734
Self-Organization of Autonomous Peers with Human Strategies
Similarly to social networks where people are connected by their social relationships, two autonomous peer nodes can be connected in unstructured peer-to-peer (P2P) networks if users in those nodes are interested in each other's data. The similarity between P2P networks and social networks, where peer nodes are people and connections are relationships, leads us to believe that human strategies in social networks are useful for improving the performance of resource discovery by self-organising autonomous peers on unstructured P2P networks. In this paper, we present an efficient social-like peer-to-peer (ESLP) model for resource discovery by mimicking different human behaviours in social networks.