Average consensus in networks of dynamic agents with switching topologies and multiple time-varying delays

In this paper, we discuss average consensus problem in undirected networks of dynamic agents with fixed and switching topologies as well as multiple time-varying communication delays. By employing a linear matrix inequality method, we prove that all the nodes in the network achieve average consensus asymptotically for appropriate communication delays if the network topology is connected. Particularly, several feasible linear matrix inequalities are established to determine the maximal allowable upper bound of time-varying communication delays. Numerical examples are given to demonstrate the effectiveness and the sharpness of the theoretical results.     

涤纶复合丝（POY＋DTY）的研发

DTY和POY网络复合丝是以聚酯直纺生产的两种不同规格的POY丝为原料,通过对加弹机进行适当改造,利用不同的加工路线,使一股POY丝经过加捻后形成DTY,再与另一股POY丝网络合股形成包芯复合丝.该复合丝利用POY丝和DTY丝的收缩差异和染色差异等不同风格特性,使得布面形成一种具有雪花状的色丁效果.该复合丝属于差别化纤维,是国家鼓励发展的项目,它具有优良的吸湿排汗性能和弹性保暖性能,是保暖内衣的首选面料,市场前景广阔.     

钻井液振动筛叠层筛网透筛率的研究

从理论上详细论述了钻井液振动筛叠层筛网对固相颗粒分离的影响 ,首次提出用透筛率的概念定量地描述这一影响 ,并进行了实例计算。研究表明 ,当上下层筛网随机叠加时对透筛率的影响有以下几种情况 :(1)当上下层筛网开孔尺寸相除的余数为零 ,任意组合叠层筛网的透筛率分别为某一常数 ;(2 )上层筛网目数一定时 ,下层筛网目数越大 ,则透筛率越小 ;(3)上下层筛网的目数相差越小 ,透筛率越小 ;(4 )任意目数的上下层筛网随机叠加后 ,其透筛率仅在一个小范围内变化 ,因此任一叠层筛网有其固有的透筛率属性。     

Study on Oxygen Isotope Fractionation in RE Oxide Minerals

ＳｔｕｄｙｏｎＯｘｙｇｅｎＩｓｏｔｏｐｅＦｒａｃｔｉｏｎａｔｉｏｎｉｎＲＥＯｘｉｄｅＭｉｎｅｒａｌｓＦａｎｇＴａｏ（方涛），ＱｉｕＹｕｚｈｕｏ（裘愉卓）（ＩｎｓｔｉｔｕｔｅｏｆＧｅｏｃｈｅｍｉｓｔｒｙ，ＡｃａｄｅｍｉａＳｉｎｉｃａ，Ｇｕｉｙａｎｇ５...     

新型超微晶软磁合金FePCCuMoSi微观结构缺陷的正电子湮没研究

用正电子湮没方法研究了新型超微晶软磁合金的微观结构缺陷，样品选用的是在不同温度下退火的Ｆｅ８１Ｐ１２Ｃ３Ｃｕ１Ｍｏ０．５Ｓｉ２．５合金，结果表明，合金的微观结构构陷大小，密度随退火温度有规律地变化，这种现象可能与非晶的晶化过程有关。     

Modeling electromigration lifetime under bidirectional currentstress

Electromigration reliability of interconnect under bidirectional current stress has been studied in a wide frequency range (mHz to 200 MHz). Experimental results show that the AC lifetime rises with the stress current frequency. The current density exponent and the activation energy of AC lifetime are found to be twice that of DC lifetime. Pure AC current stress failure at extremely high current density is believed to result from thermal migration of metal at hot/cold transition points     

Optimal solutions for a dynamic bandwidth allocation scheme in high-speed networks

In this paper, we investigate the problem of determining the optimal bandwidth allocation for a Dynamic Bandwidth Allocation Scheme (DBAS). The objective is to minimize the total amount of bandwidth required to satisfy the Quality of Service (QoS) requirements of all traffic streams. It is shown that when the performance functions satisfy a certain number of conditions, there exists a unique optimal bandwidth allocation such that, for each traffic stream, either its QoS is just satisfied or its QoS is over-satisfied and it is allocated zero bandwidth. Such an allocation is said to be efficient. It is also shown that there exists a unique efficient allocation in the entire feasible region. An iterative algorithm is developed to compute the efficient allocation employing its special properties. Numerical examples are presented to demonstrate how the algorithm works. Future extensions of this work are also discussed.Partially supported by NSERC of Canada through grants OGP14020 and STRIN-200.     

液相添加剂对PTCR陶瓷电性能的影响

液相添加剂ＡＳＴ（Ａｌ２Ｏ３＋ＳｉＯ２＋ＴｉＯ２）对ＢａＴｉＯ３陶瓷材料电性能的影响很大，随着Ａｌ２Ｏ３含量的增加，材料的电性能降低；ＳｉＯ２、ＴｉＯ２的物理特性对材料电性能影响较大；过量ＴｉＯ２对材料ＰＴＣ效应有重要影响，适当过量ＴｉＯ２含量，可得到性能优良的ＰＴＣＲ陶瓷。     

Evaluation of Qbd for electrons tunneling fromthe Si/SiO2 interface compared to electron tunneling from thepoly-Si/SiO2 interface

Electrical time-to-breakdown (TTB) measurements have shown the charge to breakdown Q_bd of gate oxide capacitors fabricated on n-type well (n-well) substrates always to be higher than that of capacitors on p-type well (p-well) substrates on the same wafer when both are biased into accumulation under normal test conditions. Here the authors correlate the higher n-well Q_bd to smooth capacitor oxide/substrate interfaces and minimized grain boundary cusps at the poly-Si gate/oxide interfaces, confirming that Fowler-Nordheim tunneling is the dominant current conduction mechanisms through the oxide. They correlate higher Q_bd to higher barrier height for a given substrate type and observe that the slope of the barrier height versus temperature plot is lower for both p-well and n-well cases with electrons tunneling from the silicon substrate. This is attributed to surface roughness at the poly-Si gate/SiO₂ interface. A poly-Si gate deposition and annealing process with clean, smooth oxide/substrate interfaces will improve the p-well breakdown characteristics and allow higher Q_bd to be achieved     

榆树林油田砂岩储层敏感性研究

榆树林油田储层粘土矿物含量较高，各种注入条件和施工条件都会对该储层造成相应的伤害，应采取相应的防护措施，为防止速敏的发生，储层的注水速度应控制在临界流速（1.0mL/min）以下，在油井转注时，可先注入1.09PV的含粘土稳定剂的进行处理，以提高产量或注入量，注入阴离子表面活性剂配置的活性水再注入地层水，不能增加地层水的渗透率，该项试验研究对指导榆树林油田的开发具有重要的意义。