Entropy Optimization Models with Convex Constraints

In this paper, we study the minimum cross-entropy optimization problem subject to a general class of convex constraints. Using a simple geometric inequality and the conjugate inequality we demonstrate how to directly construct a "partial" geometric dual program which allows us to apply the dual perturbation method to derive the strong duality theorem and a dual-to-primal conversion formula. This approach generalizes the previous results of linearly, quadratically, and entropically constrained cross-entropy optimization problems and provides a platform for using general purpose optimizers to generate ε-optimal solution pair to the problem.     

PAA-PSF交联复合膜的制备及对低浓度有机醇水溶液反渗透分离性能研究

进行了ＰＡＡ（ＰｏｌｙａｃｒｙｌｉｃＡｃｉｄ）－ＰＳＦ（Ｐｏｌｙｓｕｌｆｏｎｅ）交联复合膜的制备，研究了交联剂、添加剂对膜性能的影响，并通过扫描电镜观察了膜的断面结构．研究了ＰＡＡ－ＰＳＦ交联复合膜对低浓度有机醇类水溶液反渗透分离性能．发现对于１０００×１０－６乙醇水溶液截留率达到６６．２％，透过流束可达０．９×１０－６（ｍ３·ｍ－２·ｓ－１）．随醇的分子量的增加，截留率不断上升，对戊醇的截留率达９４．３％，而透过流束则保持相对稳定．对不同结构醇类的分离性能研究表明，截留率存在有：ｔｅｒｔ－＞ｓｅｃ－＞ｉｓｏ－＞ｎ－的规律．     

Formation Mechanism of MoO3-Doped YSr2Cu3Oy Using the Citrate Process

The formation mechanism of the synthesis of MoO₃-doped YSr₂Cu₃O _y powders using the citrate process was investigated. It was shown that the precursor phase (Sr_{1- x} Y _x )₁₄Cu₂₄O₄₁ played a crucial role in forming the superconducting phase. It was found that the precursor phase (Sr_{1- x} Y _x )₁₄Cu₂₄O₄₁ interacted with water and decomposed when it was heavily milled and heated.     

Progress in the study of mechanism of fetal scarless wound healing

From January 1987 to December 1993, 426 patients with lung cancer were operated in our hospital, among which 159 patients were diagnosed postoperatively to be N2 disease by pathology including 81 central type and 78 peripheral type lung cancer. Radical operations were performed on 135 cases, palliative operations on 24 cases. Follow up study: one-year survival rate was 71.7%, three-year survival rate 29.0% and five-year survival rate 21.7%. The main factors affecting operative results are tumor cell type, the number and location of metastatic lymph nodes and the thoroughness of dissection. Tumor staging, except T4 tumor is not a main factor influencing prognosis. The indications of operation performed on N2 lung cancer and the necessity of extensive nodal exenteration are also discussed in this article. We consider extensive hilar and mediastinal nodal exenteration necessary in order to achieve radical resection and good prognosis.     

ATM局域网仿真体系结构的研究

本文在简要叙述了基于ＡＴＭ技术进行局域网仿真的原理后，对局域网仿真体系结构作了一些探讨。考虑的重点是无连接服务和群播功能的实现     

A novel ultracompact two-mode-interference wavelength division multiplexer for 1.5-/spl mu/m operation

A novel ultracompact 2/spl times/2 wavelength division multiplexer (WDM) for 1.55-/spl mu/m operation based on highly dispersive two-mode interference (TMI) was designed, theoretically modeled, and verified using a finite-difference-time-domain (FDTD) method. A two-moded waveguide assisted with a dispersive tooth-shaped grating provided a mode-dependent reflection band of central wavelength at 1.55 /spl mu/m. The wavelengths of 1538 and 1572 nm that were at the band edges and had the lowest reflection losses and relatively high dispersion were selected for wavelength multiplexing. The result showed that the wavelengths were separated by grating dispersion in a coupler length of 75 /spl mu/m which was much shorter than the required length of 1.1 mm in a regular TMI multiplexer of no grating. Insertion loss of about 1.7 dB and channel contrast of about 12 dB were achieved.     

浅谈“水源空调“在丹东市的推广使用

本文通过对“水源空调”的介绍,结合丹东市的地质情况,分析论证其在我市推广使用的可行性。     

泥土中微量六氯环戊二烯的气相色谱分析

采用SE 3 0为固定液进行色谱柱分离 ,用外标定量法测定泥土中的微量六氯环戊二烯 ,结果最小检知量为 0 .18× 10 - 6 ,相关系数为 0 .99992。     

一种基于GE90-30PLC的飞剪自动控制系统

本文介绍了调整线材轧线精轧机前专用于切头的启停式飞剪的自动控制系统。该系统以GE90—30PLC为控制核心，辅以热金属HMD、光电编码器等元件，能很好地完成飞剪的剪切及定位。其中着重阐述了飞剪控制中各个重要参数的计算原理和方法。     

鄂尔多斯盆地姬塬-堡子湾地区长4+5油层成岩作用与储层评价

利用岩石铸体薄片鉴定、X射线衍射分析、扫描电镜分析等测试手段，对鄂尔多斯盆地姬塬一堡子湾地区延长组长4＋5油层储集岩的岩石学特征、成岩作用和物性特征进行了分析。结果表明，该储集岩为细粒的长石砂岩和岩屑长石砂岩，颗粒呈次棱角状，成分成熟度普遍较低，结构成熟度中等一较好；经历了压实、胶结、压溶和溶解等一系列成岩作用；储集岩具有低孔、低渗的特点。在以上研究基础上，结合压汞分析、孔隙组合分析，对储层进行综合评价认为，长4＋5储层可分为4类，研究区以Ⅱ、Ⅲ类（中等一差）储层为主。