关于B股回购的法律探讨

Ｂ股回购是目前研究和争议的焦点。从法律角度看，证券回购已成为国际资本市场通行的惯例，它应当允许符合条件的 Ｂ股上市公司根据公司资本结构调整需要，维护公司股价和市场形象等原因进行Ｂ股回购。     

Electronic markets in support of procurement processes along the automotive supply chain

Since the introduction of the internet, firms have continued to seek ways to use these public networks to gain competitive advantage. The procurement function is beginning to take on greater strategic importance as these networks started providing firms wider opportunities such as choices of suppliers. This aims not only to reduce procurement costs, but also to build stronger relationships with suppliers to improve quality and flexibility in meeting customer demand. This type of linkage of firms with their suppliers when the product manufactured is complex and supply-chain is heavily tiered, such as the case of the automobile industry, creates challenges to any electronic market or exchange that is aiming to support such a system. Based on discussions with some key individuals in an automotive supply chain and an in-depth analysis of a supply-chain segment, this paper explores the role electronic markets may have to play, if they are to support the procurement processes of various agents along the supply chain.     

2HDM中B→ππ衰变的新物理效应

介绍了双Higgs二重态模型 (2HDM)的结构和特点 ,具体分析了标准模型 (SM)和 2HDM中B介子衰变的有效哈密顿和Wilson系数 ,并由B→ππ衰变事例发现 2HDM的贡献对SM有较好改善。     

“该A则A，该B则B”框式结构研究

“该 A 则 A，该 B 则 B”是一种“框中框”“句中句”的复杂框式结构，其可变项 A 和 B 的语义特征较为复杂。整个结构强调理当怎么样自然就怎么样，表现出[+理应性]、[+虚拟性]、[+条件性]、[+推理性]和[+强调性]的语义特征。在语义上，该框式结构还具有特殊的语义增值性，其增值的方式主要有对比凸显增值和典型事例增值两种，而其中的增值机制就是极量原则和类比推理。     

Culture-based versus risk-based screening for the prevention of group B streptococcal disease in newborns: A review of national guidelines

BackgroundMaternal colonisation with group B streptococcus (GBS) is recognised as the most frequent cause of severe early onset infection in newborns. National and international guidelines outline two approaches to the prevention of early onset disease in the neonate: risk based management and antenatal culture-based screening. We undertook an analysis of existing national and international guidelines in relation to GBS in pregnancy using a standardised and validated instrument to highlight the different recommended approaches to care.MethodsEnglish language guidelines on the screening and management of GBS colonisation in pregnant women and the prevention of early-onset group B streptococcal disease in newborns were sought.ResultsFour guidelines met the inclusion criteria, one from the United States of America (USA), the United Kingdom (UK), Canada and New Zealand. All four were appraised as at a high standard in terms of development using the AGREE II tool. Both approaches were recommended in the guidelines with different regions of the world advocating different approaches often based on the same evidence. Guidelines from the USA recommend an antenatal culture-based approach while the UK guidelines recommend risk-based management.ConclusionBased on an AGREE II analysis, the standard of the guidelines was high despite having disparate recommendations. Both approaches to the prevention of early onset GBS infection in neonates are recommended with the split being geographically-based.     

Optimal procurement of long-term contracts in the presence of imperfect spot market

B2B spot market has grown rapidly and become an effective trading channel for commodity products. Besides long-term contract procurement from conventional suppliers (forward and option), a buyer can procure or sell commodities at any time in B2B spot market to adjust her inventory level. However, spot prices are generally volatile and the market is imperfect in the sense that spot trading may be realized with uncertainty in a given period of time and often comes with extra transaction cost. This paper considers a commodity buyer who can order forward and option contracts in advance and trade in a B2B spot market when spot price and demand are observed stochastically. Based on a single-period newsvendor model, we discuss three optimal order strategies and derive respective expected profits when the buyer is risk-neutral. The sensitivity of purchase costs, market liquidity and transaction cost is investigated. We also compare the optimal expected profits for different strategies to illustrate the effects of the two long-term contracts in the presence of the B2B spot market. We then extend our model to a multi-period setting and derive the optimal strategy. Finally, we numerically compute the optimal order strategy for a risk-averse buyer and analyze the impact of spot market, risk aversion, as well as the correlation between customer demand and spot price.     

B2C电子商务模式下多渠道分销系统研究综述

随着网络技术及电子商务的迅速发展,众多企业在保持传统零售渠道的同时,开辟电子市场直接向终端消费者出售产品。B2C电子商务模式下多渠道分销系统问题的研究近几年引起企业界和学术界的重视。本文针对近几年B2C电子商务模式下多渠道分销系统的研究成果进行了跟踪,主要从多渠道结构安排和定价、多渠道冲突与协调、多渠道运作管理等问题对国内外研究现状进行了综述,最后提出了该领域未来的研究方向。     

Nonlinear regression modeling via regularized radial basis function networks

The problem of constructing nonlinear regression models is investigated to analyze data with complex structure. We introduce radial basis functions with hyperparameter that adjusts the amount of overlapping basis functions and adopts the information of the input and response variables. By using the radial basis functions, we construct nonlinear regression models with help of the technique of regularization. Crucial issues in the model building process are the choices of a hyperparameter, the number of basis functions and a smoothing parameter. We present information-theoretic criteria for evaluating statistical models under model misspecification both for distributional and structural assumptions. We use real data examples and Monte Carlo simulations to investigate the properties of the proposed nonlinear regression modeling techniques. The simulation results show that our nonlinear modeling performs well in various situations, and clear improvements are obtained for the use of the hyperparameter in the basis functions.     

An L-statistic approach to a test of exponentiality against IFR alternatives

In this note we consider the problem of testing exponentiality against IFR alternatives. A measure of deviation from exponentiality is developed and a test statistic constructed on the basis of this measure. It is shown that the test statistic is an L-statistic. The asymptotic as well as the exact distribution of the test statistic is obtained and the test is shown to be consistent.     

慢性乙型病毒性肝炎的科学治疗与预防

乙肝在我国广泛流行,严重危害人民的健康,给病人、家庭、社会造成沉重的经济负担和巨大的精神压力,给社会发展带来不容忽视的影响。针对公众对于乙肝的恐慌心理和治疗、预防乙肝的模糊认识,文章介绍了慢性乙型病毒性肝炎(乙肝)的感染机理、乙肝病毒的传播途径和预防方法、乙肝病人的临床诊断和治疗原则。在此基础上介绍了病程进展和相关表现症状,明确了乙肝治疗的总体目标,传递了科学的治疗与预防知识,提出了预防控制乙肝宣传教育的知识要点。