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The changing epidemiology, clinical syndrome and antibiotic resistance patterns of shigellosis in Vietnamese children
Diarrhoeal diseases remain the second most common cause of death among children under-five globally, following closely behind pneumonia. In developing countries, rotavirus and Shigella spp. are thought to be the most important enteropathogens causing acute childhood diarrhoea. Systematicd ata on diarrhoea)diseases. particularly Shigella infection, in southern Viet Nam is lacking. An analysis of the historical trends in epidemiology, antibiotic susceptibility, and clinical features of Shigella infection and contemporary clinical studies of the response to antibiotic treatment in Vietnamese children were the central aims of this thesis. By analysing Shigella strains isolated from children between 1995 and 2009 I documented a transition in the dominant Shigella species causing diarrhoea from S.flexneri to S.sonnei, a change previously linked with industrialisation and economic development. During the same period there was a sharp increase of nalidixic acid resistant Shigella strains from approximately 7% to 70%. In addition, the clinical presentation appeared to be more severe and the duration of hospital stays longer. During the course of this thesis I also documented for the first time in Viet Nam Shigella spp. which harboured the plasmid-transferable drug resistance blaCTX-M genes. The occurrence of this plasmid-transferable gene may endanger the use of betalactams for this infection in the future. In a large randomised controlled trial, gatifloxacin, a new 8-methoxy-fluoroquinolone antibiotic proved comparable to ciprofloxacin for the treatment of acute dysentery including those caused by multiresistant Shigella. Although gatifloxacin has been associated with dysglycaemic side-effects in adults, this adverse effect was not observed in this study
The Entire Things They’ll Talk About Before We Get To Uncle Tang [Now Thomas]’s Lunar New Year’s Eve Party Nº6
機械学習技術の視点による通勤交通手段選択と自動車所有に関する研究
過去数十年の間に,世界は急速な都市化プロセスを経験し,人々の生活には自動車が急速に普及した。モータリゼーションは我々に経済発展の機会を与えると同時に,生活の質に影響を与える地球環境に負荷をかけている。都市の自己増殖は,自家用車の所有と使用の増加を引き起こす主要な理由である。旅行モードの選択,車両所有パターン,およびそれらの決定要因に対して影響力のあるメカニズムを理解することは,土地利用と交通計画上の政策決定に大いに役立つ。この課題は,グローバリゼーションの時代に持続可能な交通の発展を目指す途上国において,大いに注目されている。本研究では,多項ロジットモデル,ニューラルネットワーク,ランダムフォレストを用いて,プノンペン市における将来のインパクトレベルと車両所有パターンの予測を行った。交通手段選択に関して,本研究では,勾配ブースティングマシン,機械学習アルゴリズム,およびLIMEを適用して,インドネシアのジャカルタ市の大都市圏における複数交通手段によるトリップパターンとその決定要因を推定した。両方の分析は,国際協力機構(JICA)から提供された世帯インタビュー調査データを使用した。分析結果は,家計収入がプノンペンのモータリゼーションに影響を与える最も強力な変数であることを示した。合計旅行回数などの個々の旅行特性の補足,通勤目的で行われた移動回数と全体の移動距離は全て,分類子として効果的に作用した。ジャカルタ市におけるケーススタディにおいては,単一交通機関の旅行に影響を与える要因として旅行費用や移動時間といった限られた変数が選ばれる一方で,複数交通機関の旅行については幅広い変数の影響を受けていることが示された。さらに,機械学習アプローチによる予測においては,精度を予測するという点だけでなく,統計的アプローチと比較して不均衡なカテゴリを処理するという点でも優れていたことが認められた。特に,グラディエントブースティングマシンは,ビッグデータで課題を解決する際,優れた潜在能力があることが示された。これら二つの結果は,旅行行動分析の分野に関して機械学習技術を適用する優位性を示し,他の分析に関しても,機械学習技術が応用できる可能性を示唆している。In the last decades, the world has seen the rapid urbanization process with the boom of motorized vehicles. The motorization, on one hand, gives opportunities for economic development and on the other hand, it puts pressure on the environment that affects the quality of life. The self-proliferating of the city is identified as a major that causes the rise of private vehicle ownership and usage. Understanding the influential mechanism of the travel mode choice, vehicle ownership patterns, and their determinants will greatly help policymaking for land use and transportation. This issue has been paid even greater attention in developing countries that aspire to reach sustainable transportation development goals in the era of globalization.In this study, the Multinomial logit model, Neural Networks and Random Forest were applied to examine the features’ impact level and to also predict vehicle ownership patterns in Phnom Penh city. Regarding travel mode choice, this study introduces the application of Gradient Boosting Machine, a Machine Learning algorithm, and Local Interpretable Model-agnostic Explanations technique to investigate the multi-mode trip pattern and its determinants in the metropolitan area of Jakarta city, Indonesia. Both analyses used the household interview survey data provided by the Japan International Cooperation Agency (JICA). The results indicate that household income is the most powerful variable affecting motorization in Phnom Penh. Supplementation of individual trip characteristics such as total number of trips made, number of trips made for work purposes and overall travel distance all make effective contributions as classifiers. The results from the case study of Jakarta city show that there was a limit of features (travel cost, time, etc.) that affected the single-mode trip while the multi-mode travel was influenced by the wide range of variables. Furthermore, it is acknowledged that the machine-learning approach outperformed not only in terms of predicting accuracy but also in dealing with unbalanced categories when compared with the statistical approach. Especially, the Gradient Boosting Machine indicated the impressive potentiality in solving the subject with big data. This detection supplies the advantages of applying machine learning techniques in terms of, but not limited to, the field of travel behavior.室蘭工業大学 (Muroran Institute of Technology)博士(工学
INVESTIGATION OF ABILITY LIBERATION OF METALS FROM PRINTED CIRCUIT BOARDS BY MECHANICAL PROCESSES FOR PHYSICAL SEPARATION PROCESSES
Physical separation process was widely applied for the separation of metallic component from Printed Circuit Boards (PCBs) due to their advantages as friendly-environment, facilitated control, and low-cost. However, the efficiency of physical separation depends on a level of the liberation between the metallic and non-metallic components which is conducted by mechanical processing.In this study, the liberation of metals from computer PCBs was conducted in detail by mechanical processes including cutting and crushing. The obtained results demonstrate the distribution metallic and non-metallic component weighs as a function of particle sizes. The separation efficiency of metals was conducted by air separation using vacuum sorter equipment. The results showed that the comminution processes using hammer mill for reach the highest efficiency with 92 % recovery and 87 % grade of metallic components in the heavy fraction with particle size 1.0 - 1.4 mm by air separation process
Local And Global Approaches To Treat The Torsional Barriers Of 4-methyl-acetophenone Using Microwave Spectroscopy
The Fourier transform microwave spectrum of 4-methylacetophenone recorded from 8 GHz to 18 GHz under jet-cooled conditions has revealed large tunneling splittings arising from a low barrier to internal rotation of the ring methyl group and small splittings from a high torsional barrier of the acetyl methyl group. The large splittings are especially challenging to model, while the small splittings are difficult to analyze due to the resolution limit of 120 kHz. The combination of two methyl groups undergoing internal rotations caused each rotational transition to split into five torsional species, which were resolved and fitted using a modified version of the \textit{XIAM} code and the newly developed \textit{ntop} code to a root-mean-square deviation close to measurement accuracy, providing an estimate of the \textit{V} potential barriers of about 22 \wn ~and 584–588 \wn ~ for the ring and the acetyl methyl groups, respectively. The assignment was aided by separately fitting the five torsional species using odd-power order operators. Only one conformer in which all heavy atoms are located on a symmetry plane could be identified in the spectrum, in agreement with results from conformation analysis using quantum chemical calculations
Observer-based integral sliding mode control for sensorless PMSM drives using FPGA
This paper presents the design and evaluation of an observer-based integral sliding mode controller for sensorless Permanent Magnet Synchronous Motor (PMSM) drive based on the Field Programmable Gate Array (FPGA) technology. For enhancement of robustness, a flux angle estimator using an improved sliding mode observer is proposed to estimate the current and back electromotive force (EMF) as well as to derive the flux angle. These estimated values together with the computed rotor speed of the motor are fed back for the control purpose in both the current loop and the speed loop. To increase the performance of PMSM speed control, an integral sliding mode control (ISMC) is designed with integral operation to improve steady state accuracy against parameter variations and external disturbances. The developed controller has been implemented in an FPGA-based environment and the very high speed integrated circuit-hardware description language (VHDL) is adopted to show advantages of the proposed control system. By integrating the observer-based and integral sliding mode control techniques into speed control of a PMSM drive, the system performance can be substantially enhanced while improving its cost-effectiveness and reliability. The validity of the proposed approach is verified through simulation results based on Modelsim and Simulink co-simulation method. © 2013 IEEE
Экологические проблемы информационной цивилизации
Цель данного исследования - проясниться характерные черты академического взгляда, подготовленные революцией в информационной сфере. Задача, установленная автором, рассмотреть возможные проблемы, которые создает информационная цивилизация. Методологической основой для достижения поставленных целей и решения проблем является систематический подход.The purpose of this study is to clarify the features of the scientific worldview prepared by the information revolution. The task posed by the author lies in the field of considering possible problems created by the information civilization. The methodological basis for achieving the goals and solutions of the assigned task is the system-activity approach
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