Proposta de um algoritmo eficiente para a localização de faltas por relé diferencial numérico para proteção de linhas de transmissão com compensação série controlada por tiristores (TCSC)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Power system stability enhancement in a deregulated environment using FACTS devices

In deregulated versions of free-market electricity, producers will be free to send power along other utilities. The price of power strongly depends and fluctuates according to mutual benefit index of both supplier and consumer. In such a situation, strong interaction among utilities may cause instabilities in the system. As the frequency of market-based dispatch increases market forces tend to destabilize the stable system dynamics depending on the value of Ks/τλ(market dependent parameter) ratio. This tends to destabilize the coupled dynamics. The implementation of TCSC can effectively damp the inter area modes of oscillations of the coupled market system.

Modeling and control of unified power flow controller for transient stability

FACTS controllers are emerging as viable and economic solutions to the problems of large interconnected ne networks, which can endanger the system security. These devices are characterized by their fast response, absence of inertia, and minimum maintenance requirements. Thyristor controlled equipment like Thyristor Controlled Series Capacitor (TCSC), Static Var Compensator (SVC), Thyristor Controlled Phase angle Regulator (TCPR) etc. which involve passive elements result in devices of large sizes with substantial cost and significant labour for installation. An all solid-state device using GTOs leads to reduction in equipment size and has improved performance. The Unified Power Flow Controller (UPFC) is a versatile controller which can be used to control the active and reactive power in the Line independently. The concept of UPFC makes it possible to handle practically all power flow control and transmission line compensation problems, using solid-state controllers, which provide functional flexibility, generally not attainable by conventional thyristor controlled systems. In this paper, we present the development of a control scheme for the series injected voltage of the UPFC to damp the power oscillations and improve transient stability in a power system. (C) 1998 Elsevier Science Ltd. All rights reserved.

天花粉蛋白抗HIV．1构效关系及机制探讨

目的研究TCS抗HIV-1的构效关系并对机制进行探讨。方法蛋白工程技术构建14个TCS突变 体，测定各种TCS突变体的细胞毒性和抗HIV恬性。结果活性中心突变体TCSM(120—123)与TcSEl60A／E189A在失 去绝大部分RI活性的同时，也几乎完全失去抗HIV活性。而另一个活性中心突变体TCSRl22G，RI活性下降160 倍，却仍保留一定的抗HIV活性。TCSC末端删除突变体(TCS(2，TCSo和TCScl。)抗HIV活性的下降(1．4—4．8 倍)与其RI活性呈平行下降(1．2—3．3倍)；分别在C末端加上末端19个氨基酸延伸肽或KDEL信号肽的突变体 TCscl9。与TQkDEL，虽然保留全部的RI活性，但却几乎完全失去抗HIV活性；TCS抗原决定簇位点突变后对TCS 抗HIV．1括性没有显著影响，但当在抗原决定簇突变体所引入的Cys残基上加上PEG20K后，这些突变体则显著降 低了抗HIV-1的活性。TCS不能抑制HIV一1进入宿主细胞；对感染细胞和未感染细胞的融合没有抑制作用；TCS 也不能抑制HIV一1 rRT活性；TCS对病毒颗粒的直接杀伤作用不大。结论TCS抗HIV-1活性与其Rl活性显著 相关，但似乎又不是唯一的决定因素；TCS C末端氨基酸的突变影响其抗HIV．1活性；在C末端增加KDEL信号肽 序列及19aa尾肽并不能增加其抗HIV活性；抗原决定簇突变体以及PEG20K偶联TCS抗原决定簇突变体体外抗 HIV-1活性下降；抗HIV．1机制可能与对感染细胞的间接作用有关。

天花粉蛋白抗HIV-1构效关系研究及机制探讨

天花粉蛋白（Trichosanthin，TCS）是从葫芦科植物括楼（TrichosanthesKiriloii）球根中提取的一种由247个氨基酸组成的I型核糖体失活蛋白（RibosomeInactivatingProtein，RIP）。TCS具有广谱的生物学和药学活性，包括抗肿瘤、免疫抑制、中期引产以及抗病毒活性，TCS还具有抗白血病和淋巴瘤的作用。TCS能够抑制HI卜1在急性感染的T淋巴细胞和慢性感染的巨噬细胞中的复制。TCS抗HIV的机制还不清楚，一般认为与R1（RibosolneInactivating）活性有关。TCS的毒副作用限制了它在抗HIV／AIDS临床上的进一步应用。人们期望通过改造或修饰，在保留TCS抗HIV活性的同时，降低其神经毒副作用及所引起的变态反应。因此，研究TCS的抗HIV-1作用机制及构效关系，有利于拓宽TCS的临床应用适应症，也对RIP类化合物基础研究和应用研究具有重要的指导作用。本论文在实验室己有研究工作的基础上，对TCS抗HIV-1作用、机制及构效关系进一步研究。首先，采用MTT比色法检侧TcS对人T淋巴细胞系C8166、HIV-1慢性感染细胞系H9／HIV-1IIIB细胞毒性作用以及采用台盼蓝染色法检测了TCs对刺激转化的人外周血单个核细胞（PeriphejralBloodMononuclearCen，PBMC）的细胞毒性作用；以合胞体形成抑制实验检测了TCS对实验株HIV-1ms诱导C8166细胞致细胞病变的抑制作用；以捕捉HIV-1p24抗原ELISA方法检测TCS对实验．株HIV-1IIIB在急性感染C8166，细胞和慢性感染Hg细胞中复制的抑制作用、临床分离株HIV-1KMO18在PBMC中复制的抑制作用、耐药株HIV-174v在C8166细胞中复制的抑制作用。其次，利用荧光实时定量RT-PCR检测了TCS对HIV-IIIB吸附和融合宿主细胞的抑制作用；采用高效液相色谱（HighPerformanceLiquidChromatograPhy，HPLC）检测了TCS脱HIV-IRNA腺嘿呤作用；另外还检测了TCS对病毒颗粒的直接杀伤作用、TCS对HIV感染和未感染细胞融合的抑制以及对HIV重组逆转录酶活性的抑制作用。最后，利用以蛋白工程技术构建的14个TCD突变体研究其抗HIV的构效关系，其中活性中心突变体：结果表明，TCS不仅能够有效抑制实验株HIV-1mB在C8166细胞中的复制和HIV-1ms诱导宿主细胞的病变作用，还能抑制临床分离株HIV-1KM018在PMBC中的复制和耐药株HIV-174v在C8166细胞中的复制，但TCS对HIV-1在慢性感染H9细胞中的复制无直接抑制作用。TCS不能抑制HIV-1进入宿主细胞；对感染细胞和未感染细胞的融合没有抑制作用；TCS也不能抑制HIV-1重组逆转录酶活性；TCS对病毒颗粒的直接杀伤作用不大；但TCS能够使裸露的HIV-1RNA脱腺漂呤，可能TCS的脱缥岭活性或其它酶活性直接损伤病毒或者病毒感染细胞的核酸，而胞质腺嗦岭含量的增高则可以导致线粒体膜电位的降低、细胞色素C的释放、活性氧的增加和抗凋亡因子表达的下降，结果使感染细胞更多的凋亡，这可能是TCS抗HIV的一个机制。结果也表明，活性中心突变体TCSM（120-123）与TCSE160A/E189A，在失去绝大部分R工活"性的同时，也几乎完全失去抗HIV活性。、而另一个活性中心突变体TCSR122G，RI活性下降1的倍，却仍保留一定的抗HIV活性。TcSC末端删除突变体（TCSC2，TCSC4和TCSC14）抗HIV活性的下降（1.4-4.8倍）与其R1活性呈平行下降（1.2-3.3倍）。这些结果表明TCS抗HIV-1活性与其R1活性显著相关，但似乎又不是唯一的决定因素，因为我们发现二个分别在C末端加上末端19个氨基酸延伸肤或KDEL信号肤的突变体TCS饥触与TCSKDEL，虽然保留全部的RI活性，但却几乎完全失去抗HIV活性，表明有其它机制介入了TCS的抗HIV-1活性。TCS抗原决定簇位点突变后对TCS抗HIV-1活性没有显著影响，但当在抗原决定簇突变体所引入的Cys残基上加上PEG漱后，这些突变体则显著降低了抗HIV-1的活性。

l-ucon: towards layered access control with ucon

IEEE; IEEE Computer Society; IEEE Technical Committee on Scalable Computing (TCSC)

Departmental Select Committees

The idea of departmental select committees in the House of Commons was floated as long ago as the Haldane Report in 1918 and periodically mooted by figures from both left and right as varied as Amery and Laski in the inter‐war years. It was raised again during the wartime investigations of the Machinery of Government committee, only to be shot down by the then Cabinet Secretary, Sir Edward Bridges, on the grounds that it would constrain the frankness with which the Civil Service could advise ministers. Departmental select committees were not to be introduced until 1979. Ten years ago the Institute of Contemporary British History organised a symposium to review their progress. On 31 January 1996 in committee room 10 at the House of Commons the ICBH, in conjunction with the Hansard Society, held another seminar to re‐examine the development of the departmental select committee system, its successes and failings. It was chaired by George Cunningham (Labour MP 1970–82, SDP MP 1982–83). The principal participants were Sir Peter Kemp (Deputy Secretary, Treasury 1983–88, Next Steps Project Manager, Cabinet Office, 1988–92), Douglas Millar (Clerk of Select Committees, House of Commons since 1994), Dr Ann Robinson (author of Parliament and Public Spending, head of the policy unit at the Institute of Directors [IOD], 1989–95 and Director‐General of the National Association of Pension Funds Ltd since 1995), Robert Sheldon (Labour MP since 1964, Financial Secretary to the Treasury 1974–75, member of the Public Accounts Committee [PAC] 1965–70 and 1975–79 and chairman since 1983, member, Public Expenditure Committee 1972–74, and member of the Treasury and Civil Service Committee [TCSC] 1979–81) and Sandy Walkington (head of corporate affairs at BT [British Telecom] plc), with further contributions from Peter Riddell (assistant editor: politics, The Times, since 1993), Chloe Miller, Sean McDougall, Tim King and Chris Stevens.

Efeitos da compensação série na capacidade de sincronização em sistemas multimáquinas

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Estudo dos efeitos da compensação série no desempenho transitório dos sistemas de energia elétrica sob o enfoque da energia

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo da comunicação de um compensador série para rede de distribuição com o centro de controle utilizando tecnologia GPRS

Pós-graduação em Engenharia Elétrica - FEIS

Utilização de sinais adicionais estabilizantes para o amortecimento de oscilações de baixa frequência do sistema elétrico de potência multimáquinas

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Regulação de tensão utilizando compensador série controlado a tiristores para sistemas de distribuição

Pós-graduação em Engenharia Elétrica - FEIS

Controle coordenado de múltiplos dipositivos facts com vistas à estabilidade transitória de SEE

Pós-graduação em Engenharia Elétrica - FEIS

Compensador série controlado a tiristores na distribuição: Compensação dinâmica

Pós-graduação em Engenharia Elétrica - FEIS