延边区域竞争优势的源泉--全球化背景下的企业集群

企业出现以来，企业组织形式随着技术进步和市场需求的变化不断演进．21世纪，中小企业和企业集群逐渐成为主流，并成为全球化背景下延边区域竞争优势的源泉．本文立足延边现状，分析了延边企业集群的类型选择和发展问题，并提出了对策．     

基于电子商务环境下的中小企业核心竞争力构建探究

电子商务的出现为中小企业提供了快捷廉价的信息和服务,扩宽了中小企业的发展空间,为中小企业核心竞争力的提高创造了条件。本文分析了中小企业核心竞争力的现状,提出了我国中小企业在当前电子商务背景下存在的问题,并提出从开发核心技术、建立规范的企业制度、制定企业的战略目标以及创建企业特色的企业文化四个方面采取措施来提高核心竞争力。     

Transmission congestion and voltage profile management coordination in competitive electricity markets

This paper describes a generalized active/reactive iterative coordination process between GENCOs and the Independent System Operator (ISO) for active (transmission congestion) and reactive (voltage profile) management in the day-ahead market. GENCOs apply priced-based unit commitment without transmission and voltage security constraints, schedule their units and submit their initial bids to the ISO. The ISO executes congestion and voltage profile management for eliminating transmission and voltage profile violations. If violations are not eliminated, the ISO minimizes the transmission and voltage profile violations and sends a signal via the Internet to GENCOs. GENCOs reschedule their units taking into account the ISO signals and submit modified bids to the ISO. The voltage problem is addressed and a linear model is formulated and used in the proposed method. The voltage problem is formulated as a linear programming with a block-angular structure and Dantzig-Wolfe decomposition is applied to generate several smaller problems for a faster and easier solution of large-scale power systems. Two 36 unit GENCOs are used to demonstrate the performance of the proposed generalized active/reactive coordination algorithm.     

我国企业科技发展弊端之分析

通过对经济发展与科技发展模式的分析 ,提出做大我国企业的经济规模 ,提高我国企业的国际竞争力 ,进行技术开发与技术创新。采取企业与科技部门相结合 ,处理科技部门与企业之间的关系及科技成果转化困难的问题     

产业市场竞争结构分析方法及其应用

针对产业市场环境因素分析法的不足,提出运用结构分析法来解决产业市场环境分析问题,产业市场结构分析的重点是竞争关系分析,本文在阐述具体分析方法的同时给出在焊管产业的一个应用案例。     

Competitive Separation of Lead,Cadmium, and Nickel from Aqueous Solutions Using Activated Carbon: Response Surface Modeling,Equilibrium, and Thermodynamic Studies

In this study, the competitive separation of lead, cadmium, and nickel ions from aqueous solutions using a commercial activated carbon (AC) has been investigated and optimized using response surface methodology (RSM). The optimal conditions to reach the highest adsorption capacity for these metals were found as follows: initial pH = 6.3, temperature = 56.8°C, and shaking speed = 308 rpm. Under these conditions, the sequence of adsorption capacity toward the metal ions was as follows: Pb (II): 9.44 mg g^?1 > Cd (II): 9.37 mg g^?1 > Ni (II): 4.52 mg g^?1. The effect of shaking speed on the adsorption capacity of AC was higher than the effects of the initial pH and temperature, indicating the more important role of physisorption than chemisorption in the adsorption of these metal ions. This was confirmed by the results of thermodynamic studies. The equilibrium adsorption data were fitted to the Freundlich, Langmuir adsorption isotherm models and the Dubinin–Radushkevich model parameters were evaluated. All the models were tested and all were shown to represent the experimental data satisfactorily. The thermodynamic parameters such as ΔH, ΔS, and ΔG were computed from the experimental data. These values show that the adsorption is endothermic and spontaneous. The positive value of ΔS° indicates increasing of randomness at the solid/liquid interface during the adsorption of metal ions on AC.     

总银杏酸对酪氨酸酶活性的影响及动力学研究

研究了总银杏酸(C13∶0,C15∶1,C17∶2,C15∶0,C17∶1)对酪氨酸酶单酚、二酚酶活力的影响及其抑制动力学。在28℃,p H=6.8的Na2HPO4-Na H2PO4缓冲体系中,测试总银杏酸对酪氨酸酶催化反应进程的影响、酶活性抑制率以及抑制动力学参数。实验表明,总银杏酸对酪氨酸酶单酚酶和二酚酶活性均有抑制作用,单酚酶和二酚酶活力下降50%的总银杏酸质量浓度(IC50)分别为0.03 g/L和0.20 g/L。总银杏酸能延长单酚酶反应的迟滞时间,对二酚酶的抑制作用表现为可逆效应。Lineweaver-Burk图显示总银杏酸对二酚酶的抑制作用表现为竞争性抑制,抑制常数KI=75.20 mg/L。     

Real-time multiple people tracking using competitive condensation

The CONDENSATION (Conditional Density Propagation) algorithm has a robust tracking performance and suitability for real-time implementation. However, the CONDENSATION tracker has some difficulties with real-time implementation for multiple people tracking since it requires very complicated shape modelling and a large number of samples for precise tracking performance. Further, it shows a poor tracking performance in the case of close or partially occluded people. To overcome these difficulties, we present three improvements: First, we construct effective templates of people's shapes using the SOM (Self-Organizing Map). Second, we take the discrete HMM (Hidden Markov Modelling) for an accurate dynamical model of the people's shape transition. Third, we use the competition rule to separate close or partially occluded people effectively. Simulation results shows that the proposed CONDENSATION algorithm can achieve robust and real-time tracking in the image sequences of a crowd of people.     

Competitive randomized algorithms for nonuniform problems

Competitive analysis is concerned with comparing the performance of on-line algorithms with that of optimal off-line algorithms. In some cases randomization can lead to algorithms with improved performance ratios on worst-case sequences. In this paper we present new randomized on-line algorithms for snoopy caching and the spin-block problem. These algorithms achieve competitive ratios approachinge/(e–1) 1.58 against an oblivious adversary. These ratios are optimal and are a surprising improvement over the best possible ratio in the deterministic case, which is 2. We also consider the situation when the request sequences for these problems are generated according to an unknown probability distribution. In this case we show that deterministic algorithms that adapt to the observed request statistics also have competitive factors approachinge/(e–1). Finally, we obtain randomized algorithms for the 2-server problem on a class of isosceles triangles. These algorithms are optimal against an oblivious adversary and have competitive ratios that approache/(e–1). This compares with the ratio of 3/2 that can be achieved on an equilateral triangle.Supported in part by the Center for Discrete Mathematics and Theoretical Computer Science (DIMACS), an NSF Science and Technology Center funded under NSF Contract STC-88-09648 and supported by the New Jersey Commission on Science and Technology.     

On the power of randomization in on-line algorithms

Against in adaptive adversary, we show that the power of randomization in on-line algorithms is severely limited! We prove the existence of an efficient simulation of randomized on-line algorithms by deterministic ones, which is best possible in general. The proof of the upper bound is existential. We deal with the issue of computing the efficient deterministic algorithm, and show that this is possible in very general cases.A previous version of this paper appeared in the22nd ACM STOC Conference Proceedings. Part of this research was performed while A. Borodin and A. Wigderson were visitors at the International Computer Science Institute, and while G. Tardos was a visitor at the Hebrew University.