Search Results: 1 - 10 of 14060 matches for " Anna;Morimoto "
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Patterns in Stroke Occurrence on Warm Days in Winter by Associations Analysis [PDF]
Hiroshi Morimoto
Abstract: There is increasing interest in the effects of meteorological factors on stroke occurrence. A number of studies have found that cold exposure was a trigger to the onset of cerebral infarction in winter. It was believed that the case of stroke occurrence on warm days in winterwas just a coincidence and negligible. The main objective of this study was to offer the evidence against the above belief. We aimed to find typical patterns among stroke occurrences in case the weather became warmer in winter. Associations analysis was conducted using daily data of emergency transport at Nagoya City in Japan. Typical patterns were identified among risky stroke occurrences even for the case that the weather became warmer in winter. These findings will contribute to an accurate forecast of stroke occurrence in winter.
Hidden Markov Models and Self-Organizing Maps Applied to Stroke Incidence [PDF]
Open Journal of Applied Sciences (OJAppS) , 2016, DOI: 10.4236/ojapps.2016.63017
Abstract: Several studies were devoted to investigate the effects of meteorological factors on the occurrence of stroke. Regression models had been mostly used to assess the correlation between weather and stroke incidence. However, these methods could not describe the process proceeding in the back-ground of stroke incidence. The purpose of this study was to provide a new approach based on Hidden Markov Models (HMMs) and self-organizing maps (SOM), interpreting the background from the viewpoint of weather variability. Based on meteorological data, SOM was performed to classify weather patterns. Using these classes by SOM as randomly changing "states", our Hidden Markov Models were constructed with "observation data" that were extracted from the daily data of emergency transport at Nagoya City in Japan. We showed that SOM was an effective method to get weather patterns that would serve as "states" of Hidden Markov Models. Our Hidden Markov Models provided effective models to clarify background process for stroke incidence. The effectiveness of these Hidden Markov Models was estimated by stochastic test for root mean square errors (RMSE). "HMMs with states by SOM" would serve as a description of the background process of stroke incidence and were useful to show the influence of weather on stroke onset. This finding will contribute to an improvement of our understanding for links between weather variability and stroke incidence.
Hidden Markov Models to Estimate the Lagged Effects of Weather on Stroke and Ischemic Heart Disease [PDF]
Applied Mathematics (AM) , 2016, DOI: 10.4236/am.2016.713122
Abstract: The links between low temperature and the incidence of disease have been studied by many researchers. What remains still unclear is the exact nature of the relation, especially the mechanism by which the change of weather effects on the onset of diseases. The existence of lag period between exposure to temperature and its effect on mortality may reflect the nature of the onset of diseases. Therefore, to assess lagged effects becomes potentially important. The most of studies on lags used the method by Lag-distributed Poisson Regression, and neglected extreme case as random noise to get correlations. In order to assess the lagged effect, we proposed a new approach, i.e., Hidden Markov Model by Self Organized Map (HMM by SOM) apart from well-known regression models. HMM by SOM includes the randomness in its nature and encompasses the extreme cases which were neglected by auto-regression models. The daily data of the number of patients transported by ambulance in Nagoya, Japan, were used. SOM was carried out to classify the meteorological elements into six classes. These classes were used as "states" of HMM. HMM was used to describe a background process which might produce the time series of the incidence of diseases. The background process was considered to change randomly weather states, classified by SOM. We estimated the lagged effects of weather change on the onset of both cerebral infarction and ischemic heart disease. This fact is potentially important in that if one could trace a path in the chain of events leading from temperature change to death, one might be able to prevent it and avert the fatal outcome.
Growing industrialization and our damaged planet. The extraterritorial application of developed countries' domestic environmental laws to transnational corporations abroad
Tetsuya Morimoto
Utrecht Law Review , 2005,
Abstract: There is serious concern over environmental devastation caused by commercial activities worldwide. Transnational corporations (TNCs) have substantially contributed to such devastation through their 'double standards' practice. TNCs have been conducting their operations in developing host countries in accordance with much lower environmental standards than those adopted in their home countries or in developed host countries. Considering the seriousness of environmental destruction and the social responsibility of TNCs, it is argued that TNCs should be subject to the same stringent environmental standards in developing host countries as well. Recently, foresighted TNCs have voluntarily adopted uniform stringent environmental standards; however, it seems unlikely that the majority of TNCs will follow suit. The international harmonization of environmental standards also appears unlikely due to irreconcilable national interests. Given the economic dependence on TNCs and the lack of enforcement mechanisms, developing countries do not seem to be able to regulate TNCs effectively. The only remaining possible solution seems to be the extraterritorial application of the environmental rules of the TNCs' home countries. Although controversial, this approach would be viable if the rules in question would not directly apply to foreign affiliates of TNCs and if it were implemented through multilateral action by the OECD member states.
Digital Watermarking Technology with Practical Applications
Norishige Morimoto
Informing Science The International Journal of an Emerging Transdiscipline , 1999,
Abstract: Digital watermarking technology has been actively studied and developed by a number of institutions and companies since mid 90s. This area draws more and more attention as one of the key technology elements for content management, copyright protection and copy control of digital contents. This article discusses several different types of digital watermark application, particularly the application of digital watermarks for DVD copy control. This would be the first digital watermark application requiring worldwide standardization.
On the degeneration ratio of tunnel numbers and free tangle decompositions of knots
Kanji Morimoto
Mathematics , 2009, DOI: 10.2140/gtm.2007.12.265
Abstract: In this paper, we introduce a notion called n/k-free tangle and study the degeneration ratio of tunnel numbers of knots.
On tangle decompositions of twisted torus knots
Mathematics , 2011,
Abstract: In the present paper, we will show that for any integer n>0 there are infinitely many twisted torus knots with n-string essential tangle decompositions.
On composite types of tunnel number two knots
Abstract: Let $K$ be a tunnel number two knot. Then, by considering the $(g, b)$-decompositions, $K$ is one of (3, 0)-, (2, 1)-, (1, 2)- or (0, 3)-knots. In the present paper, we analyze the connected sum summands of composite tunnel number two knots and give a complete table of those summands from the point of view of $(g, b)$-decompositions.
On Heegaard splittings of knot exteriors with tunnel number degenerations
Abstract: Let $K_1, K_2$ be two knots with $t(K_1)+t(K_2)>2$ and $t(K_1 # K_2)=2$. Then, in the present paper, we will show that any genus three Heegaard splittings of $E(K_1 # K_2)$ is strongly irreducible and that $E(K_1 # K_2)$ has at most four genus three Heegaard splittings up to homeomorphism. Moreover, we will give a complete classification of those four genus three Heegaard splittings and show unknotting tunnel systems of knots $K_1 # K_2$ corresponding to those Heegaard splittings.
On composite twisted torus knots
Abstract: In the present note, we will show that there are infinitely many composite twisted torus knots.