反凝析现象对雅克拉凝析气处理工艺的影响

雅克拉凝析气田位于塔里木盆地北部，地处新疆维吾尔自治区阿克苏地区境内，它是中国石化集团公司西北分公司探明并投入开发的最大凝析气田，采用衰竭式开采。通过对井口物流的相态研究，认识了凝析气的反凝析规律，采取了提高凝析气中C^＋₃收率的方法，以确保外输干气的烃露点达到管输要求，并提高该气田开发的经济效益。在工艺方案设计过程中，通过多种工艺方案比选，确定选用膨胀机进口压力为6.0 MPa的膨胀机制冷工艺， C^＋₃收率达到92％以上，外输干气烃露点满足管输要求。     

Defocusing image to pattern contact holes using attenuated phase shift masks

The patterning of contact holes by selecting out-of-focus image plane (defocus) using attenuated phase shift masks (APSM) has been studied. Defocus is found to enhance the image modulation at low partial coherence for contact holes with negative local average of mask function. Semi-dense holes up to 130 nm in 8% APSM have been printed by 0.5 μm defocus at a partial coherence of 0.31 using KrF scanner with highest numerical aperture of 0.68. However, these holes were closed with in-focus imaging. Defocus is also found to be beneficial for patterning the pitches that have extensive side lobes with in-focus imaging.     

基于EDGE系统信道估计实现方案的研究

研究了基于ＥＤＧＥ系统接收机中信道估计的实现方案，并对算法的各项性能做出评估。首先论述了算法的采用及其理论依据。接着，说明了信道预估计的原理及方法。最后，针对ＭＡＴ－ＬＡＢ及 ＤＳＰ上的仿真结果，比较了各项系数对于系统性能改善所具有的影响和作用，对系统特性作了较为详细的分析总结。     

Adaptive motion control using neural network approximations

In this paper, we present a new adaptive technique for tracking control of mechanical systems in the presence of friction and periodic disturbances. Radial Basis Functions (RBFs) are used to compensate for the effects of nonlinearly occurring parameters in the friction and periodic disturbance model. Theoretical analysis, such as stability and transient performance, is provided. Furthermore, the performance of the adaptive RBF controller and its non-adaptive counterpart are compared.     

多级机站通风新模式和矿井通风技术的新进展

文中详细论述了我国“九五”期间金属矿山在多级机站通风系统改造中涌现出的先进技术 ,反映了我国矿山通风技术的发展现状。同时 ,探讨了矿井通风技术的发展方向 ,对矿井通风系统的改造研究具有一定意义     

Topology preservation of template-based 6-subiteration reduction operations

Generally, a reduction operation (e.g., thinning and shrinking) on 3D binary images can be represented as a set of reduction templates where every object voxel of the image satisfying any template is turned to a background voxel. Generally, it is rather difficult, error-prone and time-consuming for verifying the topological soundness of a 3D parallel reduction operation. This paper proposes sufficient conditions of time complexity O(n) for verifying the topological soundness of 3D parallel 6-subiteration reduction operations of n templates where such a kind of 3D reduction operations is performed alternatively from the six orthogonal directions to turn object voxels to background voxels. By such sufficient conditions, the topology soundness of a 3D 6-subiteration parallel reduction operation can be verified by checking each and every of its templates.     

Control of discrete time nonlinear systems with a time-varying structure

In this paper, we present a control methodology for a class of discrete time nonlinear systems that depend on a possibly exogenous scheduling variable. This class of systems consists of an interpolation of nonlinear dynamic equations in strict feedback form, and it may represent systems with a time-varying nonlinear structure. Moreover, this class of systems is able to represent some cases of gain scheduling control, Takagi-Sugeno fuzzy systems, as well as input-output realizations of nonlinear systems which are approximated via localized linearizations. We present two control theorems, one using what we call a “global” approach (akin to traditional backstepping), and a “local” approach, our main result, where backstepping is again used but the control law is an interpolation of local control terms. An aircraft wing rock regulation problem with varying angle of attack is used to illustrate and compare the two approaches.     

Stability robustness of networked control systems with respect to packet loss

This paper is concerned with stability analysis of discrete-time networked control systems over a communication channel subject to packet loss whose behavior is modeled by an i.i.d Bernoulli process with a packet dropping probability bounded by a constant. A necessary and sufficient condition for stability is obtained. A packet dropping margin is introduced as a measure of stability robustness of a system against packet dropping, and a formula for it is derived. A design method is proposed for achieving a large margin subject to a constraint that the system has a set of prescribed nominal closed-loop poles.