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Quasi-Z-Source Based Bidirectional DC-DC Converter and Its Control Strategy

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Chinese Journal of Electrical Engineering 2019年第1期5卷 1-9页

作者： yuba Raj Kafle Saad Ul Hasan Graham E.Town School of Engineering Macquarie UniversityNSW 2109Australia

This paper presents a quasi-Z-source based isolated bidirectional DC-DC converter(qZIBDC)for renewable energy *** converter utilizes a dual active bridge circuit with a quasi-Z-source network on both sides,so the converter works as buck/boost converter from either *** has a wider input/output voltage operating range,soft-switching capabilities without additional devices,and higher boost capability than a traditional dual active bridge *** from that,shoot-through states are incorporated in its operating cycle to boost the input voltage resulting in high reliability of the proposed *** to the symmetrical structure of the circuit,there is no defined high voltage or low voltage side as in traditional isolated bidirectional DC-DC *** operating principle and control strategy of the proposed converter are *** and experimental results are provided to verify the effectiveness of the proposed converter topology and its control strategy.

关键词： Bidirectional DC-DC converter dual active bridge impedance source quasi-Z-source DC-DC converter

Absorption and emission modulation in a MoS2–GaN（0001） heterostructure by interface phonon–exciton coupling

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Photonics Research 2019年第12期7卷 1511-1520页

作者： yuba POUDEL JAGODA SLAWINSKA PRIYA GOPAL SAIRAMAN SEETHARAMAN ZACHARIAH HENNIGHAUSEN SWASTIK KAR FRANCIS D'SOUZA MARCO BUONGIORNO NARDELLI ARUP NEOGI Department of Physics University of North TexasDentonTexas 76203USA Department of Chemistry University of North TexasDentonTexas 76203USA Department of Physics Northeastern UniversityBostonMassachusetts 02115USA

Semiconductor heterostructures based on layered two-dimensional transition metal dichalcogenides(TMDs)interfaced to gallium nitride(Ga N)are excellent material systems to realize broadband light absorbers and emitters due to their close proximity in the lattice *** surface properties of a polar semiconductor such as Ga N are dominated by interface phonons,and thus the optical properties of the vertical heterostructure are influenced by the coupling of these carriers with *** activation of different Raman modes in the heterostructure caused by the coupling between interfacial phonons and optically generated carriers in a monolayer MoS_2–Ga N(0001)heterostructure is *** excitonic states in MoS_2 are close to the interband energy state of intraband defect state of Ga *** functional theory(DFT)calculations are performed to determine the band alignment of the interface and revealed a type-I *** close proximity of the energy levels and the excitonic states in the semiconductors and the coupling of the electronic states with phonons result in the modification of carrier relaxation *** of the excitonic absorption states in MoS_2 is measured by transient optical pump-probe spectroscopy and the change in emission properties of both semiconductors is measured by steady-state photoluminescence(PL)emission *** is significant red-shift of the C excitonic band and faster dephasing of carriers in MoS_***,optical excitation at energy higher than the bandgap of both semiconductors slows down the dephasing of carriers and energy exchange at the *** and blue-shifted PL emission is observed in MoS_*** N band-edge emission is reduced in intensity at room temperature due to increased phonon-induced scattering of carriers in the Ga N *** results demonstrate the relevance of interface coupling between the semiconductors for the development of optical and electronic applications.

关键词： spectroscopy. coupling interface

Recent Advances in Ketamine Research: An Update

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Open Journal of Anesthesiology 2020年第3期10卷 89-100页

作者： Thapa yuba Raj Ren Quan Department of Anesthesiology Zhongda Hospital School of Medicine Southeast University Nanjing China

Ketamine is a sedative N-methyl-D-aspartate receptor antagonist, considered as a dissociative anesthetic medication. Ketamine inhibits the voltage-gated Na+ & K+ channels and serotonin and dopamine re-uptake and affects specific receptors, such as α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), kainate and aminobutyric acid A receptors. It is commonly administered by a parenteral route. On administration, ketamine has particular properties that are potentially involved during anesthetic induction including the enhancement of descending inhibition and anti-inflammatory effects. Recent literature reviews report that ketamine possesses various clinically beneficial properties. Sub-dissociative dose/Lower dose of ketamine (LDK) has potential as well as safe effects in clinical practice for the management of acute and chronic pain in postoperative room as well as Emergency Department (ED), along with cognitive function and depression in Psychiatric Department. Moreover, pharmacology of ketamine includes bronchodilators, neuro-protective actions, anti-shock, anti-suicide, and anti-tumor action immune system disorder. The purpose of this review is to illustrate recent advances in mechanism of action, mode of administration and indication of clinical uses of ketamine. In this article various new uses of ketamine have been shown, mainly related to its NMDAR antagonism and the clinical implementation and significance of low dose/sub dissociative dose of ketamine. In future, beyond being used as the adjuvant general anesthesia, it also can be used as a rapid acting antidepressant and anti-suicidal agent for mental disorders, and adjuvant analgesia to avoid potential risk and side effects of opioids in emergency department and in post-operative care.

关键词： Ketamine Dissociative Anesthesia Sedative Pain Management Anti-Depressant Agent Pediatrics Anesthesia

Enhancing Performance in Multi Channel Wireless Networks Using Channel Selection Strategies

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Enhancing Performance in Multi Channel Wireless Networks Usi...

作者： Devkota yuba Raj 华中科技大学

学位级别：硕士

Multi-channel Medium Access Control （MAC） protocols have been used to improve the performance in IEEE 802.11 wireless standard. In‘n’channel environment, practically it is impossible to increase the performance by‘n’times however improvements can be made as near as possible. This paper uses ns-2 simulations to show the improvement of performance in multi channel environment than IEEE 802.11 DCF environment. Ns-2.29 is extended with Hyacinth framework to work in multi-channel environment. IEEE 802.11 DCF is modified to work in multi-channel environment. The MAC protocol used is Dedicated Control Channel MAC Protocol and Receiver Based Channel Selection Strategy is studied. The common multi channel hidden terminal problem has been an issue in multi-channel environment and it is shown that Multi channel MAC has better approach to solve that problem. The channel selection scheme reduces the frame losses and improves performance. The performance metrics studied to compare two protocols are throughput, delay and throughput with increased packet size. The IEEE 802.11 DCF protocol is modified so that it can work in the multi-interface framework. Multi-channel environment increases the performance of a wireless system but it also complicates the process. There are various issues [28] [42] [45] in multi-channel framework and each of them have to be deal with ease. Although improving the throughput in‘n’channel environment by‘n’times is limited only in ideal case, however, throughput can go as much as possible. The simulation performed later in chapter, increases throughput by about 40% and explained that increasing the packet size can increase the throughput but within certain criteria. The performance also depends on how well the channel selection is done. In IEEE 802.11 DCF, there is no need to choose the channel being it a single channel but in multi-channel interface, it is necessary to choose a suitable channel. My work includes Receiver Based Channel Selection

关键词：多频道无线网路介质访问控制协议信道选择策略吞吐量

事先给予布托啡诺对全身麻醉诱导期舒芬太尼诱发的咳嗽和肌僵直的影响：随机对照实验

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事先给予布托啡诺对全身麻醉诱导期舒芬太尼诱发的咳嗽和肌僵直的...

作者： yuba Raj Thapa(塔帕) 东南大学

学位级别：硕士

前言:全身麻醉诱导过程中阿片类药物常可引发咳嗽反射和肌僵直需要设法抑制。目的:本研究旨在评估静脉注射布托啡诺在全麻诱导过程中对舒芬太尼药物引起的咳嗽和肌僵直的抑制作用。方法:将106例年龄在18～75岁之间,在全麻诱导下接受择... 详细信息

前言:全身麻醉诱导过程中阿片类药物常可引发咳嗽反射和肌僵直需要设法抑制。目的:本研究旨在评估静脉注射布托啡诺在全麻诱导过程中对舒芬太尼药物引起的咳嗽和肌僵直的抑制作用。方法:将106例年龄在18～75岁之间,在全麻诱导下接受择期手术的ASAⅠ、Ⅱ患者随机分为两组。存在以下疾病或情况的病人将被排除,包括:有哮喘病史、慢性咳嗽、长期吸烟、肝肾功能不全、接受支气管扩张剂或类固醇治疗、2周内发生上呼吸道感染、服用血管紧张素转化酶抑制剂或布托啡诺喏过敏。实验组(布托啡诺组)静脉注射布托啡诺1mg,对照组注射等量生理盐水。注射布托啡诺1mg(1ml)或等容量生理盐水30秒后,在5秒内给予患者舒芬太尼0.3mcg/kg and 0.4mcg/kg,并通过监测仪记录平均动脉压(MAP)、心率(HR)和脉搏血氧饱和度(SPO),并观察注射舒芬太尼后2分钟内咳嗽次数(咳嗽严重程度)和肌肉僵硬的严重程度。结果:根据排除标准排除5例患者。实验组51名和对照组50名共101名患者(54名女性,47名男性)完成了实验方案。两组的基本资料具有可比性。在研究期间,在给药布托啡诺或生理盐水(T0)之前、开始麻醉(T1)、舒芬太尼注射后30秒(T2),插管后1分钟(T3)3分钟(T4)和5分钟(T5)分别记录MAP、HR和SpO。两组比较,各时点各生命体征指标没有统计学差异。舒芬太尼药物引起的咳嗽发生率对照组为29.4%,布托啡诺组为2%(P<0.001),其中对照组中轻度咳嗽和中度咳嗽的发生率分别为23.5%和5.9%,布托啡诺组轻度咳嗽的发生率为2%,无中度咳嗽(P<0.001);两组患者均无严重咳嗽。与对照组相比,布托啡诺组患者肌肉僵硬的发生率较低(9.8%vs2%),但差异无显著性意义(P=0.205)。结论:静脉注射布托啡诺有助于抑制舒芬太尼所致的咳嗽,降低肌肉僵硬的发生率,对全身麻醉诱导过程的血液动力学变化不形成显著影响。

关键词：阿片类舒芬太尼咳嗽肌肉强直

Assessment of Phytochemical, Antioxidant and Antimicrobial Activities of Some Medicinal Plants from Kaski District of Nepal

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American Journal of Plant Sciences 2020年第9期11卷 1383-1397页

作者： Lekha Nath Khanal Khaga Raj Sharma yuba Raj Pokharel Surya Kant Kalauni Central Department of Chemistry Tribhuvan University Kirtipur Kathmandu Nepal Faculty of Life Science and Biotechnology South Asian University New Delhi India

Medicinal plants have been known to treat simple to life-threatening diseases in different communities of Nepal for many years. This study aims to analyze the phytochemicals as plant secondary metabolites, evaluate the antioxidant and antibacterial activities of Rubus ellipticus, Ziziphus mauritiana, Pyrus pashia, and Drynaria coronans extracts that are commonly being used as traditional medicine. Phytochemical analysis was performed to investigate the plant’s secondary metabolites such as polyphenols, alkaloids, flavonoids, terpenoids, reducing sugar, glycosides, tannins, carotene, phytosterols, coumarins, saponins, and anthracenes. The methanol extracts of the plants were used to evaluate the in vitro antioxidant activity by using 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical and the antibacterial activity against Staphylococcus aureus (ATCC 25923), Klebsiella pneumoniae (ATCC 700603), <

关键词： Medicinal Plant Phytochemical Antioxidant Antibacterial Activity Resazurin

SIGMA-1数据流巨型机-对新一代巨型机系统的挑战

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计算机工程与科学 1989年第3期11卷 43-52页

作者： KEI HIRAKI KENJI NISHIDA SATOSHI SEKIGUCHI TOSHIO SHIMADA TOSHITSUGU yuba 黄志毅

SIGMA-1是一种很有前途的、基于数据流体系结构的实用计算机原型。它在性能上超过了传统的冯氏计算机。这种大规模数据流机用于科学技术计算。它正由日本通产省的电子技术实验室进行最后阶段的设计和制造。本文概述了SIGMA-1的系统结构... 详细信息

SIGMA-1是一种很有前途的、基于数据流体系结构的实用计算机原型。它在性能上超过了传统的冯氏计算机。这种大规模数据流机用于科学技术计算。它正由日本通产省的电子技术实验室进行最后阶段的设计和制造。本文概述了SIGMA-1的系统结构,讨论了最近进行的性能测试,同时还给出了为达到SIGMA-1计划中提出的100MFLOPS性能指标所作的设计决策和有关体系结构的问题。最后简述了SIGMA-1计划的历史。

关键词：数据流计算机 SIGMA-1 巨型机体系结构设计决策性能测试处理单元指令集性能指标日本通产省

A Human T Lymphotropic Virus Type 1 Carrier Coinfected with <i>Mycobacterium intracellulare</i>and <i>Pneumocystis jirovecii</i>with a Characteristic Compositional Change of Bone Marrow Cells

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Open Journal of Respiratory Diseases 2017年第3期7卷 110-116页

作者： Sayaka Uda Shinsuke Shiotsu Ayaka Omura Ryosuke Hamashima Akihiro Yoshimura Naoko Kurisu Tomoya Sagawa Koichi Hasegawa Tatsuya yuba Chieko Takumi Seiko Ono Noriya Hiraoka Noriya Hiraoka Department of Respiratory Medicine Japanese Red Cross Kyoto Daiichi HospitalKyotoJapan Department of Respiratory Medicine Graduate School of MedicineKyoto UniversityKyotoJapan Department of Infection Control and Prevention Japanese Red Cross Kyoto Daiichi HospitalKyotoJapan

Human T lymphotropic virus type 1 (HTLV-1) is endemic in the southern part of Japan. Infection of the virus can cause adult T cell leukemia/lymphoma (ATL), while most infected individuals remain in a carrier state for a long period of time. Although rare cases of carriers, like ATL patients, who developed opportunistic infections, have been reported, hematological changes of carriers who are prone to opportunistic infections have not been well defined. Here, we present a case of an HTLV-1 carrier who developed Mycobacterium intracellulare infection and Pneumocystis jirovecii pneumonia (PcP) simultaneously. Flow cytometric analysis of bone marrow cells revealed an aberrant compositional change similar to that in ATL patients. This suggests the presence of a pre-ATL state prior to the development of ATL, which is notable in terms of underlying cellular immunodeficiency.

关键词： Human T Lymphotropic Virus Type 1 Carrier Immunodeficiency Pneumocystis jirovecii

新连接管CT增强扫描中螺旋流盐水冲洗对增强扫描效果的影响

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国际医学放射学杂志 2014年第1期 92-93页

作者： M.Kidoh T.Nakaura K.Awai K.yuba T.Kobayashi Y.K.Park 刘洋 Diagnostic Radiology Amakusa Medical Center kameba 854-1 Amakusa Kumamoto 863-0046 Japan

目的评价一种新开发、能产生螺旋流的连接管对肝动脉期及门静脉期主动脉和肝强化的影响。方法80例病人随机分为两组,分别应用新连接管及传统连接管。在30 s

关键词： CT增强扫描盐水冲洗对比剂对比增强螺旋流