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Search Results: 1 - 10 of 212786 matches for " 刘盼 "
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模糊—重复学习复合控制策略在并联型有源滤波器中的应用
,
电工技术学报 , 2011,
Abstract: 考虑到实际运行中并联型有源电力滤波器APF系统参数无法精确获得,提出了一种由模糊控制与重复学习组合的复合控制策略。在具体分析重复学习参数对系统补偿性能的影响之后,针对其学习因子Ks及反馈比例系数Kr详细设计了模糊控制器。并对基于LCL滤波器的并联型有源电力滤波器复合控制策略做仿真,仿真结果表明了其可行性和有效性。
涡轮叶栅叶顶间隙泄漏流动实验研究

大连理工大学学报 , 2013, DOI: 10.7511/dllgxb201306004
Abstract: 针对一种高负荷涡轮叶栅,利用低速矩形叶栅风洞实验研究叶顶间隙泄漏流动.研究了不同叶顶间隙和不同来流冲角情况下,涡轮叶栅的流场结构和气动性能.研究工况包括无间隙,0.5%、1.0%、1.5%叶高间隙和±10°、±5°、0°冲角.通过五孔探针获得矩形叶栅出口截面上总压、气流角以及速度分布;通过叶片表面开设的静压孔,获得叶片中部以及靠近叶顶截面的叶片表面静压分布.实验结果表明:叶顶间隙的存在增强了叶栅顶部的二次流动,恶化了上半叶展的流动状况,涡系结构发生了改变.随着叶顶间隙的增大,叶栅总压损失增加,气流偏转不足/过偏现象加剧;随着冲角的增大叶栅总压损失增加.
Studies on Eutrophicated Water Quality Improvement by Three Flowers
三种花卉对富营养化水体的水质净化作用研究

LIU Pan,

水生态学杂志 , 2011,
Abstract: 用紫叶酢浆草(Oxalis triangularis)、凤眼莲(Eichhornia crassipes)和大漂(Pistia stratiotes)作为试验对象,研究了其生长状况及对三种不同富营养化水体的净化效果,分析了三种花卉对水体中总磷、总氮和氨氮的吸附能力。结果表明,三种花卉在富营养化水体中可以正常生长。大漂对三种不同富营养化程度水体的总磷吸收率分别为93.58%、97.72%、96.65%、紫叶酢浆草为89.57%、83.76%、86.45%、凤眼莲为90.11%、85.07%、91.46%。;对于不同富营养化程度水体中总氮的吸收结果是大漂为89.05%、90.18%、73.5%、紫叶酢浆草为68.32%、59.73%、72.90%、凤眼莲为68.45%、71.49%、71.53%;大漂对不同富营养化水体中氨氮的吸收率为85.80%、91.48%、88.60%、紫叶酢浆草为77.51%、72.07%、89.68%、凤眼莲为68.64%、90.90%、90.88%。结果表明,三种花卉均能显著改善富营养化水体的水质。各项指标综合分析表明,大漂对富营养化水体的净化效果最为明显;凤眼莲次之。
认知老化中有意控制对自动抑制的调节作用
,谢宁,吴艳红
心理学报 , 2010,
Abstract: 结合比例控制范式与基于空间位置的返回抑制范式, 探讨了认知老化过程中自上而下的有意认知控制对自动抑制的调节作用。结果表明, 当线索有效率由50%提升至80%时, 两组被试的返回抑制量均下降, 老年组表现为返回抑制消失, 但年轻组出现返回抑制的反转, 表明有意认知控制对自动抑制的调节作用受认知老化的影响而发生衰减。同时文章还就认知老化机制的新兴理论—— 执行衰退假说进行了讨论。
认知老化中有意控制对自动抑制的调节作用
,谢宁,吴艳红
心理学报 , 2010,
Abstract: ?结合比例控制范式与基于空间位置的返回抑制范式,探讨了认知老化过程中自上而下的有意认知控制对自动抑制的调节作用。结果表明,当线索有效率由50%提升至80%时,两组被试的返回抑制量均下降,老年组表现为返回抑制消失,但年轻组出现返回抑制的反转,表明有意认知控制对自动抑制的调节作用受认知老化的影响而发生衰减。同时文章还就认知老化机制的新兴理论——执行衰退假说进行了讨论。
中国股指期货异常交易处置机制探析中国股指期货异常交易处置机制探析
庆富,
- , 2016,
Abstract: 异常交易事件近年来时有发生,这极大损害了证券市场的基本功能及其市场效率。为防范股指期货异常交易的发生并消除其带来的消极影响,文章首先从驱动因素角度对国内外异常交易经典案例进行了剖析。据此认为,股指期货市场异常交易主要是指由于不可抗力、技术故障、重大差错或市场操纵等致使股指期货市场无法正常交易、发生交易错误或价格大幅波动等现象,进而严重影响市场基本功能的交易行为;其异常交易行为主要是在市场联动化、产品复杂化、交易多样化、高频交易增加、结算结构更新和电子交易快速发展的背景下产生的,并多由交易系统本身的脆弱性、新技术下的高频交易频发、交易人员的疏忽或犯错、交易机制的固有缺陷和证券账户和托管体系的不健全等原因引起的,且具有突发性、重大性和负面性的特点。为此,根据“数值标准”和“人工认定”异常交易的国际准则,文章从价格信息、交易量信息以及投资者交易行为角度给出了异常交易的识别指标:价格、期货及其标的物(或现货)价差、交易量、持仓量的异常变化,异常的自买自卖和对敲行为,以及信息披露前的巨额交易、关联账户的异常报价等行为。鉴于此,文章系统给出了以价格限制、技术修正和交易者要求为主要手段的前端控制办法,以及以临时停牌、临时停市、暂缓交收、取消交易、自行补救、强化交易规则为主要手段的事后处置机制,从而为期货交易所科学防范和处置异常交易提供了较可靠的参考依据。
Abstract:The abnormal trading events often come up in recent years, which largely damage the fundamental function and market efficiency in securities markets. In order to prevent abnormal trades and their effects in Chinese stock index futures market, this paper firstly analyzes the classic cases at home and abroad from the factor-drived viewpoint. Thus, the abnormal trading of stock index futures is defined as the phenomenon of no normal trading, transaction error or huge fluctuation of price in stock index futures market, which affects the basic function of market trading seriously, due to the force majeure, technical failure, major errors or market manipulation. The behavior of abnormal trading of stock index futures market is coming up mainly based on the background of co-movement of markets, complication of products, diversification of trades, increasing of high-frequency trading, updating of settlement structure and rapid development of electronic trading, mainly focuses on the reasons of fragility of trading system itself, emergence of high-frequency trading under the new technology, negligence or mistakes of traders, intrinsic defects of trading mechanism, and incomplete securities account and managed system, and has characteristics of emergency, materiality and negativity. According to the international standards of “numerical standard” and “labor standard”, this paper gives the abnormal changes of price, difference of futures and underlying (or spot), trading volume and open interest, the abnormal behaviors of wash sale and bucketing, the huge trading before disclosure of information, the abnormal quotation of affiliate accounts, and so on, from the aspects of price information, information of trading volume, and behavior of traders. Then, the paper improves the front control measures based on price limit, technical correction and trader requirements, and the ex-post treatment mechanisms based on sidecar, temporarily closed, suspended delivery, cancel transaction,
预期寿命、年金市场与经济行为
,王欣雨
- , 2019, DOI: 10.16538/j.cnki.jfe.2019.02.003
Abstract: 随着经济的发展,人口预期寿命持续增加,社会养老压力逐步加大;年金作为养老保障的重要支柱,其需求也在不断增大。文章在一个包含信贷约束和年金市场的三期生命周期模型框架下,从理论上分析了预期寿命增加和年金市场发展对典型消费者人力资本投资、储蓄行为、退休决策和预期终生劳动供给的影响。研究发现,随着预期寿命的增加,消费者会增加人力资本投资水平,增加储蓄率,但是退休行为和预期终生劳动供给的变化不确定,取决于年金市场的完善程度和外生的市场利率水平。如果年金市场不完善程度较高或市场利率水平较低,预期寿命增加会引起退休提前。但是即使进入劳动力市场的时间推迟,退出劳动力市场的时间提前,由于生存概率增加,预期终生劳动供给的变化并不确定。文章还发现,当预期寿命保持不变时,随着年金市场的不断完善,消费者会提前退休。
多轴商用车驱动防滑硬件在环试验研究
Research on Anti-skidding Regulation System of Commercial Vehicles Based on Hardware in Loop Bench

黄智,
- , 2015,
Abstract: 以三轴商用车ASR为研究对象,研究了低附路面下发动机扭矩控制和分离路面下差动制动控制的驱动防滑控制算法,设计了发动机扭矩PID控制器和以滑转量和轮加速度为门限的差动制动门限逻辑控制算法,并研制了ABS/ASR控制器。采用Trucksim、Labview RT及转向、制动系统实物搭建硬件在环仿真平台,对开发的ABS/ASR 控制器进行典型工况试验分析。试验结果表明:所开发的驱动防滑控制算法能较好地抑制车轮滑转,提高了车辆动力性和燃油经济性。
This paper presents studies on the anti-skidding regulation (ASR) for tractor with three axles. The anti-skidding algorithms, i.e. PID controller for engine torque on low friction road and the logic threshold controller for differential braking on the split friction road are designed. An anti-lock braking system (ABS)/ASR controller is developed. Hardware in loop (HIL) simulation bench is built, which is constituted of Trucksim, Labview real-time operating system, and actual steering and brake parts. ABS/ASR electronic control unit (ECU) is tested with typical operation conditions on HIL bench. Experimental results show that the proposed anti-skidding algorithms and the developed ABS/ASR ECU can restrain the skidding of driving wheels effectively, therefore, improve vehicle maneuverability and lateral stabilities
发电系统可靠性随负荷率变化规律研究
Study on the Power System Reliability Variation with Load Rate
 [PDF]


Smart Grid (SG) , 2014, DOI: 10.12677/SG.2014.46034
Abstract:
基于削峰填谷和等比例调整等负荷率调整策略,提出调整策略对应的负荷调整算法;基于此,建立系统可靠性指标随系统负荷率变化的样条插值模型。两种负荷率调整策略均针对给定时段(如一年或一天)内,在满足负荷电能需求下,调整负荷谷峰差及负荷曲线,即在系统平均负荷不变的前提下改变系统最大负荷及其他时段负荷,以达到提高负荷率的目的。应用IEEE-RTS 79系统验证了模型的有效性。算例表明:随着系统负荷率的提高,系统可靠性呈非线性上升规律,即提高系统负荷率可提高系统可靠性;但是,当负荷率提高到一定程度时,系统可靠性的提高会出现明显的饱和现象。
Load rate adjustment strategies based on reducing peak and filling valley and the proportion of load shifting are presented, and the algorithm for the load adjustment is also presented. The rela-tionship between the system reliability and the load rate is modeled using the spline interpolation method. Both the two load rate adjustment strategies can adjust the peak-valley difference and the load curve satisfying load demand in a given period of time; that is, the maximum load and the load in other times of the system are changed with the same average load in order to improve load rate. The validity of the model is verified using the IEEE-RTS 79 system. Results indicate that with the increase of the system load rate, the system reliability increases in a non-linear way, which also means the reliability performance of the system can be improved by increasing the system load rate; however, when the loading rate increases to a certain extent, saturation will arise in the sys-tem reliability.
发输电组合系统可靠性随系统负荷变化的规律研究
Study on the Reliability Variation of Generation and Transmission System with Load Rate
 [PDF]


Smart Grid (SG) , 2014, DOI: 10.12677/SG.2014.46033
Abstract:
本文分析了发输电组合系统主要可靠性指标,如:LOLP、LOLF和EENS,随系统负荷的变化规律,以拟合的规律曲线连续、光滑等为目标,建立系统可靠性指标随系统负荷变化的三次样条插值模型。通过插值边界条件、插值点导数等信息,即可求解该模型。结合该模型,可建立电力系统可靠性预测估计模型,以避免负荷变化时可靠性的重复评估。将该模型应用于RBTS测试系统。算例表明:系统可靠性随负荷呈非线性的变化规律;当负荷变化时,可直接应用该模型预测估计系统可靠性,其平均绝对百分误差约2.0%。
The rules between the reliability indices of generation and transmission system, such as: LOLP (loss of load probability), LOLF (loss of load frequency), EENS (expected energy not supplied), and the system load are analyzed. The relationship model between the power system reliability and system load rate is modeled using cubic spline interpolation, and the model can be solved according to the interpolation boundary conditions, the interpolation points and derivative information. Therefore, a fast evaluation technique based on the proposed model for the reliability of power systems can be obtained, which can avoid the duplication of reliability evaluation with multi-load levels. The proposed model is applied to the RBTS system. Results indicate that the relationship between the system reliability and load rate is non-linear variation. The average error for the evaluation on the reliability in these cases is about 2.0% when the load changes.
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