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Synthesis of Sulfated Cyclodextrin Amphiphiles with Liposomal Encapsulation Properties

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Journal of Encapsulation and Adsorption Sciences 2015年第3期5卷 144-154页

作者： Tetsuya Furuike Koichi Nasu Hiroshi tamura Faculty of Chemistry Materials and Engineering Kansai University Suita Japan

A novel class of amphiphiles with sulfate groups at the C-6 position and palmitoyl groups at the C-2, 3 positions of α-, β-, and γ-cyclodextrin (CD) were efficiently synthesized. These compounds formed stable monolayers with high collapse pressures at the air-water interface. The mixed monolayer behaviors of the 6-O-sulfated CD amphiphiles (SO3-CDC16) in the presence of dipalmitoyl phosphatidylcholine (DPPC) and cholesterol were discussed using the surface pressure-molecular area (π-A) isotherms. The collapse pressures showed maxima at molar ratios of SO3-CDC16 lower than 10 mol%. A morphological analysis of the liposomes containing DPPC and 4 mol% SO3-CDC16 formed in PBS was carried out using transmission electron microscopy with negative staining, and vesicles with maximum diameters of 350-500 nm were observed. Moreover, the releasing ability of these liposomes was examined using a fluorescent compound, calcein. It was clearly shown that liposomes containing SO3-CDC16 could release encapsulated calcein more easily than liposomes consisting only of DPPC, and that the release rate depended on the phase transition temperature of the SO3-CDC16 included in the liposome membrane.

关键词： Cyclodextrin Amphiphile Liposome Encapsulation

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龙卷风导致高速列车倾覆风险评估与管理

自然灾害学报 2022年第3期31卷 75-84页

作者：杨庆山左有嘉回忆田村幸雄重庆大学土木工程学院重庆400045

龙卷风是一种极具破坏力的自然现象,随着高铁技术的不断发展,有必要进行龙卷风对于高铁列车可能造成的影响开展风险评估和管理工作。为此,本文提出了龙卷风影响下高速列车倾覆概率分析方法。该方法对已有的气象资料进行统计整理,采用蒙... 详细信息

龙卷风是一种极具破坏力的自然现象,随着高铁技术的不断发展,有必要进行龙卷风对于高铁列车可能造成的影响开展风险评估和管理工作。为此,本文提出了龙卷风影响下高速列车倾覆概率分析方法。该方法对已有的气象资料进行统计整理,采用蒙特卡洛模拟方法,分别使用威布尔分布模拟龙卷风强度、长度和均匀分布模拟龙卷风发生位置、方向、时间。将模拟得到的龙卷风与高铁的运行时刻表结合,得出两者相对位置关系,以此对列车进行受力分析和倾覆判断。本文通过日本案例来详细说明,以日本55年龙卷风数据和东海道线列车信息为基础,模拟得到50000年内列车倾覆以及穿过铁路的概率分别为8.1×10^(-5)和5.3×10^(-3),同时也发现不同车速下倾覆概率与单位时间内列车数量均呈线性正相关,且车速越大拟合曲线斜率越大;在列车数量不变情况下,通过调整列车发车间隔可以降低19%的倾覆风险。

关键词：高铁倾覆龙卷风灾害风险评估蒙特卡洛模拟

The Novel Current Control for Virtual Synchronous Generator

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Journal of Power and Energy Engineering 2020年第2期8卷 78-89页

作者： Atsushi Umemura Rion Takahashi Junji tamura Department of Electrical and Electronic Engineering Kitami Institute of Technology Kitami Japan

In recent years, power generation using renewable energy sources has been developed as a solution to the global warming problem. Among these power generation methods, wind power generation is increasing. However, as the penetration level of wind power generation increases, the low inertia and lack of synchronous power characteristics of the penetrated power system can have a significant impact on the transient stability of the grid. The virtual synchronous generator provides the ability of virtual inertia and synchronous power to interconnected inverters. The interconnected inverter with the virtual synchronous generator ability uses, in general, PI control based current controller. This paper proposes a new current-control method and compares it with conventional methods. The proposed current control is a method that follows virtual synchronous generator model that changes every moment by solving the discrete-time linear quadratic optimal control problem for each sampling time interval. The new method follows the conventional method, and therefore the reactive power fluctuation can be suppressed and the interconnected inverter will be downsized.

关键词： Wind Energy Generation State Feedback Electric Current Control Linearization Techniques Discrete Time Model Following Control Virtual Synchronous Generator

A Study of Discrete-Time Optimum Current Controller for the Virtual Synchronous Generator under Constraints

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Smart Grid and Renewable Energy 2020年第1期11卷 1-20页

作者： Atushi Umemura Rion Takahashi Junji tamura Department of Electrical and Eslectronic Engineering Kitami Institute of Technology Kitami Japan

In recent years, power generation using renewable energy sources has been increasing as a solution to the global warning problem. Wind power generation can generate electricity day and night, and it is relatively more efficient among the renewable energy sources. The penetration level of variable-speed wind turbines continues to increase. The interconnected wind turbines, however, have no inertia and no synchronous power. Such devices can have a serious impact on the transient stability of the power grid system. One solution to stabilize such grid with renewable energy sources is to provide emulated inertia and synchronizing power. We have proposed an optimal design method of current control for virtual synchronous generators. This paper proposes an optimal control method that can follow the virtual generator model under constrains. As a result, it is shown that the proposed system can suppress the peak of the output of semiconductor device under instantaneous output voltage drop.

关键词： Wind Energy Generation Virtual Synchronous Generator Electric Current Control Optimal Control Discreate-Time Model Following Control Multi-Objective Genetic Algorithm

Component-Oriented Reliability Analysis Based on Hierarchical Bayesian Model for an Open Source Software

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American Journal of Operations Research 2011年第2期1卷 25-32页

作者： Yoshinobu tamura Hidemitsu Takehara Shigeru Yamada Graduate School of Science and Engineering Yamaguchi University Ube Japan

The successful experience of adopting distributed development models in such open source projects includes GNU/Linux operating system, Apache HTTP server, Android, BusyBox, and so on. The open source project contains special features so-called software composition by which several geographically-dispersed compo-nents are developed in all parts of the world. We propose a method of component-oriented reliability as-sessment based on hierarchical Bayesian model and Markov chain Monte Carlo methods. Especially, we fo-cus on the fault-detection rate for each component reported to the bug tracking system. We can assess the reliability for the whole open source software system by using the confidence interval for each component. Also, we analyze actual software fault-count data to show numerical examples of reliability assessment for OSS.

关键词： Open Source Software Reliability Bayesian Model Markov Chain Monte Carlo Method

Stability Enhancement of Small-Scale Power Grid with Renewable Power Sources by Variable Speed Diesel Power Plant

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Journal of Power and Energy Engineering 2020年第3期8卷 1-17页

作者： Rion Takahashi Atsushi Umemura Junji tamura Department of Earth Energy and Environmental Engineering Kitami Institute of Technology Kitami Japan

This paper proposes a power control method to improve a stability of a small-scale power grid with renewable energy sources. In an isolated small- scale power grid such as an island, diesel power plant is main power source which has an environmental burden and expensive running cost due to high priced fossil fuel. Thus, expanding installation of the renewable energy sources such as a wind power is strongly desirable. Such fluctuating energy sources, however, harm power quality of the small-scale power grid, and in addition, conventional power plant in the small-scale power grid cannot, in general, stabilize the grid system with such fluctuating power sources. In this study, Variable Speed Doubly-Fed Induction Generator (VS-DFIG) is proposed to be in-stalled at a diesel power plant instead of a conventional Fixed Speed Synchronous Generator (FS-SG), because quick control of a power balance in the small-scale power grid can be achieved by using the inertial energy of VS-DFIG. In addition, utilization of a Battery Energy Storage System (BESS) is also considered to assist cooperatively the VS-DFIG control. As a result of the simulation analysis by using the proposed method, it is verified that frequency fluctuations due to renewable energy source can be effectively reduced by quick power control of the VS-DFIG compared to the conventional FS-SG, and further control ability can be obtained by utilizing BESS. Moreover, the transient stability of a small-scale power grid during a grid fault can also be enhanced.

关键词： Small-Scale Power Grid Variable Speed Doubly-Fed Induction Generator (VS-DFIG) Diesel Power Plant Wind Power Battery Energy Storage System (BESS)

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关于黄土高原草业和种植业的建立

干旱区资源与环境 1993年第Z1期7卷 346-348页

作者： Saburo tamura 东京大学

1.引言黄土高原覆盖着地球上最广(580,000km^2)和最厚(50—100m)的黄土沉积物。早在人类历史以前,高原上生长着大量的植被。传统上黄土高原被称为中国文化与农业的摇篮。然而由于人类的影响,特别是长期不合理的农业生产行为,使高原自然... 详细信息

1.引言黄土高原覆盖着地球上最广(580,000km^2)和最厚(50—100m)的黄土沉积物。早在人类历史以前,高原上生长着大量的植被。传统上黄土高原被称为中国文化与农业的摇篮。然而由于人类的影响,特别是长期不合理的农业生产行为,使高原自然生态系统完全破坏。现在,荒芜的地貌由无数沟谷和秃岭组成,更严重的是本区土壤侵蚀依然严重。

关键词：黄土高原引种

Near-Infrared Polarimetric Iaming of the Becklin-Neugeba Object and Its Associated Nebula

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Near-Infrared Polarimetric Iaming of the Becklin-Neugeba Obj...

Compact Hybrid Subsystem of 16 Channel Optical Demultiplexer, 2x2 Switches, Optical Power Monitors and Control Circuit

中国天文学会恒星分会2004年学术年会

作者： M.tamura National Astronomical Observatories of Japan

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光学学报 2003年第S1期23卷 259-260页

作者： Kenichiro Takahashi Toshihiko Kishimoto Shintaro Mouri Youichi Hata Hideaki Yusa Mitsuaki tamura Kazuhito Saito Hisao Maki Sumitomo Electric Industries Ltd. 1 Taya Sakae Yokohama Japan

A compact hybrid subsystem of 16channel optical demultiplexer, 2x2 switches, optical power monitors and control circuit board is developed. The subsystem is able to add or drop arbitrary optical channels and monitor t... 详细信息

关键词： circuit board