摘要：未来活动通讯系统瞄准提供很高的数据传播率，甚至在象高速度的车轮轨道火车，磁悬浮火车火车，高速公路车辆，飞机，指导导弹或太空船那样的高活动性的情形。一个特别地重要的商业应用程序是对高速度的宽带的强壮、增加的世界范围的要求无线通讯(多达 574.8 ? km/h 测试速度或 380 ? km/h 广告速度)为象为旅客的机载的娱乐服务那样的应用程序在铁路，提供的数据，声音和录像满足，火车控制，训练派遣，火车传感器地位处理和监视。在如此的高活动性的情形，有很多通讯挑战，包括快移交，更新的地点，当模特儿的高速度的隧道，评价和均等， anti-Doppler 传播技术，快力量控制，和奉献网络建筑学。因为在很高速度的情形的信号传播将不可避免地经历 s ……

摘要：Power System Stabilizer (PSS) was proposed during 1960s to solve the low frequency oscillation problem raised by the wide application of the high-gain fast-response exciters. The fundamentals of PSS design lie in the angle compensation to increase the damping torque, which, since then, has become an important principle in designing the various power system dampers, such as SVC, TCSC, UPFC. Although many papers have been dedicated to the application of this principle, it is interesting to note that in the real industry applications PSS parameters have to be carefully tuned on site in spite of its mature design theory. So does the classical PSS design theory really meet the PSS design demand? By combining the frequency domain and the time domain analysis, this paper reinvestigates the basic idea behind the classical PSS design theory. The paper clarifies the con-cepts of the synchronous torque as well as the damping torque and proves that the classical PSS design principles based on these concepts are not theoretically sound. Then the paper discusses the Linear Optimal Controller Design method and ana-lyzes its relations with the conventional PID design. By doing so the paper reveals the real mechanism of the PSS and proposes to use more systematic and advanced control tools to enhance the controller performance.

摘要：A critical safe distance(CSD)model in V2V(vehicle-to-vehicle)communication systems was proposed to primarily enhance driving safety by disseminating warning notifications to vehicles when they approach calculated *** elaborately analyzing the vehicular movement features especially when braking,our CSD definition was introduced and its configuration method was given through dividing radio range into different communication *** on our definition,the needed message propagation delay was also derived which could be used to control the beacon frequency or ***,the detailed CSD expressions were proposed in different mobility scenarios by fully considering the relative movement status between the front and rear *** results show that our proposed model could provide reasonable CSD under different movement scenarios which eliminates the unnecessary reserved inter-vehicle distance and guarantee the safety at the same *** compared time-headway model always shows a smaller CSD due to focusing on traffic efficiency whereas the traditional braking model generally outputs a larger CSD because it assumes that the following car drives with a constant speed and did not discuss the scenario when the leading car suddenly *** from these two models,our proposed model could well balances the requirements between driving safety and traffic throughput efficiency by generating a CSD in between the values of the two models in most cases.

摘要：This paper presents a new developed anthropomorphic robot dexterous hand:HIT/DLR Hand Ⅱ.The hand is composed of an independent palm and five identical modular fingers,and each finger hasthree degree of freedom(DOFs)and four *** the actuators and electronics are integrated in thefinger body and the *** to using a new actuator,drivers and a novel arrangement,both thelength and width of the finger is about two third of its former *** using the wire coupling mecha-nism,the distal phalanx transmission ratio is kept exactly 1:1 in the whole movement *** packingmechanism which is implemented directly in the finger body and palm not only reduces the size of wholehand but also make it more ***,the new designed force/torque and positionsensors are integrated in the hand for increasing multisensory *** evaluate the performances ofthe finger mechanism,the position and impedance control experiments are conducted.

摘要：过渡金属磷化物是电催化设计中的新兴材料,而多元金属磷化物因其能显著提高电催化活性而备受关注.然而,由于不同种类金属前驱物之间水解和缩合速率的差异,当前有关超过两种金属元素和化学计量比精确控制的多元金属磷化物的报道非常少.因此,合理设计多元金属磷化物的组成对提高其催化性能具有重要意义.本工作通过直接磷化二价过渡金属离子氢氧化物的合成策略,制备了能够精确控制化学计量比(x:y:z=(1–10):(1–10):1)的分级结构Co_(x)Ni_(y)Fe_(z)P,其中具有最优组分的Co_(1.3)Ni_(0.5)Fe_(0.2)P在析氧反应(OER)中展示了优异的催化活性和高稳定性.密度泛函理论计算表明,相对于其他组分的过渡金属磷化物,Co_(1.3)Ni_(0.5)Fe_(0.2)P在费米能级附近的态密度明显增加,这可以增强催化剂对OH−的吸附,从而提升OER性能.

摘要：因可自发响应外部刺激而发生体积溶胀并引起其光学性能变化,胆甾型液晶微粒备受关注并在溶剂传感、防伪图案等方面具有广泛应用.胆甾型液晶微粒在溶剂中呈现中心颜色和刷结构颜色的协同变化.但由于刷结构颜色变化的复杂性,科学家们仅关注胆甾型液晶微粒中心颜色在传感中的应用,尚未有其刷结构颜色变化机理及相关应用的报道,这极大地限制了胆甾型液晶微粒的潜在应用.本文揭示了一种胆甾型液晶微粒的新型传感机理,并结合胆甾型液晶微粒中心颜色变化及刷结构颜色变化,发展了新型的溶剂传感器.与传统系统相比,该传感器提供了更为丰富的传感信息.采用反应性介晶、反应性手性掺杂剂、非反应性液晶分子和光引发剂通过微流控装置制备及光聚合得到了胆甾型液晶微粒.所制备的胆甾型液晶微粒分别在微粒的中心处和刷结构处均呈现丰富的色彩.中心反射颜色的可逆变化归因于分子萃取引起的体积收缩及溶剂溶胀引起的体积膨胀的竞争性效应.而胆甾型液晶微粒刷结构的丰富色彩归因于其在不同溶剂中的双折射效应.本文考察了中心/刷微粒在多达16种溶剂中的协同变色行为,提出了协同颜色变化的机理,并展示了这种变色聚合物微粒在多溶剂传感检测和图案显示中的应用.本文有望为开发具有可设计纳米结构的刺激响应性先进功能材料提供新的见解,拓展其在传感、防伪及图案显示等方面的技术应用.

摘要：In this paper, we focus on energy-efficient transceiver and relay beamforming design for multi-pair two-way relay system. The multi-antenna users and the multi-antenna relay are considered in this work. Different from the existing works, the proposed algorithm is energy-efficient which is more applicable to the future green network. It considers both the sum-MSE problem and the power consumption problem for the users under the relay power constraint. Based on the optimal condition decomposition(OCD) method, the energy-efficient precoders at the users can be designed separately with limited information exchanged. The proposed relay beamforming algorithm is based on the alternative direction method of multipliers(ADMM) which has simpler iterative solution and enjoys good convergence. Simulation results demonstrate the performance of the proposed algorithms in terms of power consumption and MSE performance.

摘要：薄膜中自由传输水通道的建立对高效脱盐至关重要,然而靶向合成具有这种传输通道的薄膜材料非常具有挑战性.本研究利用分子设计策略,合成了具有刚性和开放结构的多孔芳香骨架(PAF)膜,以达到调控水传输过程的目的.具有三角形结构的腈基单体在三氟甲磺酸的催化下形成了PAF-98系列膜材料.采用刚性和特定几何形状的单体所合成的膜材料具有4.5-6.7Å的孔道,能够有效分离水分子(2.8Å)和钠盐离子(7.2Å).同时,合成的PAF膜具有很好的柔软性和连续性,是一种理想的海水淡化膜.反渗透实验表明,三种PAF膜对水分子都具有选择性透过的能力,其中PAF-98-E膜具有优异的脱盐效果:水通量为547.1 L m^(-2)h^(-1),钠盐离子的截留率为90%,该性能优于现有报道的膜材料.此外,PAF-98-E膜还能够高效去除实际海水中各种阳离子,在海水淡化中具有广阔的应用前景.

摘要：有不同配置的七个经销商被 constructal 途径设计并且优化。他们的流动分发表演和精力驱散被计算液体动力学(CFD ) 调查并且比较模拟。CFD 模拟的可靠性被在一个盘子上有所有散布矩形隧道的分发者的实验验证。结果证明散布隧道的对称在流动分发的表演上有明确的影响。增加隧道分叉的代将改进流动分发一致性，但是在另一方面增加精力驱散。在所有 sevenconstructal 经销商，有两分配置的分发者， Y 类型连接和直相连隧道之中，为它的更好的流动分发表演和更少的精力驱散被推荐。

摘要：将具有高催化活性的材料与等离激元金属纳米材料复合是制备局域表面等离激元共振增强电催化剂的常用策略.然而,这种复合方式不仅会降低等离激元材料的局域表面等离激元共振强度,同时会改变等离激元电磁场的逸散方式以及热电子在复合结构内部的传输途径,无法实现最佳的等离激元增强效果.在此,我们选择了简单的Ag@Pt双金属纳米立方体作为研究对象,深入探究了热电子在金属异质结构内部的激发和传输机制以及其在电化学析氢反应中的贡献.相应的实验和理论结果证实,Pt在Ag表面的复合会改变等离激元电磁场的逸散方式,促进激发产生更多热电子,同时热电子可以通过级联传输方式转移至复合结构表面,显著增强电催化反应.这项工作为等离激元金属异质结构催化剂的设计和应用提供了重要参考.