Concentrated supply chain membership and financial performance: Chain- and firm-level perspectives

This study reports evidence that concentrated 3-firm supply chains achieve superior financial performance, and that supply chains’ financial performance varies systematically with measures of chain concentration and chain duration. Results from firm-level analyses suggest that the profitability benefits of supply chain relationships are captured predominantly by downstream chain members, whereas cash cycle benefits are realized throughout the supply chain. Firm-level tests also reveal that chain members’ financial performance varies systematically with measures of downstream bargaining power, downstream relationship duration, and degree of supply consolidation. The study's chain- and firm-level analyses employ data extracted from sample firms’ publicly available financial reports, including their major customer disclosures under Statement of Financial Accounting Standards Nos. 131 (1997) and 14 (1976).     

基于投入要素影响的中国物流地区差距研究

文章基于集中度指数和面板数据模型,采用2002~2010年间中国31个省份的面板数据,分析了中国物流的地区差距及投入要素对地区差距的影响。结果表明:我国物流发展水平存在显著的地区差距,东部地区明显强于中西部地区;在投入要素中,信息化水平对物流发展水平的影响较大,物流基础设施的影响较小,而物流从业人员的影响未见;我国的物流发展正处于结构调整期,信息化水平差距对物流发展水平差距的贡献最大。     

专业化交易地理集中、区域市场一体化与浙中内陆城市圈层化——“义乌商圈”的空间效应分析

基于专业化交易地理集中促成的总合交易费用节约,义乌市场不仅衍生出周边产业集群,从而提升义乌城市集聚度,并进一步引致周边的浙中城市群走上圈层化的发展路径,构建起基于自主层级体系的城市共同体.本文借助新兴古典城市网络分层模型刻画了圈层化的微观机制,并启示内陆城市形成自主共同体,以获取类似海滨城市优势的途径.     

基于fluent的综采工作面采空区内瓦斯浓度场研究

本文通过数值模拟采空区内瓦斯浓度场,从理论上确定了瓦斯浓度的分布情况。进而在对综采工作面瓦斯治理提供了科学的理论依据。     

美国早期制造业集中的转变及其对中国西部开发的启示

本文通过引述Krugman的中心 -外围区域模型 ,详细分析了美国早期制造业中心从位于东北部、大西洋中部沿海地区向中西部地区转移的条件、过程。本文发现 ,美国中西部地区制造业的发展是与该地区人口数量特别是城市人口快速增长、内部运输系统效率提高、暂时维持与制造业发达地区运输成本分不开的。联系到中国改革开放以来地区差距总体上是处于不断扩大的趋势之中 ,缩小地区差距的前提条件是实现西部地区产业结构的升级 ,而这一目标实现的前提条件是西部地区城市化的发展和地区内部交通运输效率的提高。     

Market structure and competitive conditions in the Arab GCC banking system

This paper investigates the market structure of Arab GCC banking industry during the years of 1993–2002 using the most frequently applied measures of concentration k-bank concentration ratio (CRk) and Herfindahl–Hirschman Index (HHI) and evaluates the monopoly power of banks over the ten years period using the ‘H-statistic’ by Panzar and Rosse. The results show that Kuwait, Saudi Arabia and UAE have moderately concentrated markets and are moving to less concentrated positions. The measures of concentration also show that Qatar, Bahrain and Oman are highly concentrated markets. The Panzar–Rosse H-statistics suggest that banks in Kuwait, Saudi Arabia and the UAE operate under perfect competition; banks in Bahrain and Qatar operate under conditions of monopolistic competition; and we are unable to reject monopolistic competition for the banking market in Oman.     

超细全尾砂连续充填工艺技术的研究与开发

冬瓜山铜矿采用阶段空场嗣后充填采矿法,设计生产能力13000t/d,充填能力3850m3/d,年需充填量120万立方。矿块分二步骤回采,即先采矿房,后采矿柱,为控制地压活动,采用隔三采一和隔一采一的采矿顺序。在矿石中有25%的难选矿石,为提高选矿回收率因此矿石粒级细且尾砂含硫较高,若用分级尾砂充填矿山充填材料缺口很大,同时在充填料浆中含有一定的有害气体。因此采用全尾砂高浓度连续充填和选择适宜的高强度充填胶结材料是冬瓜山铜矿实现安全文明生产,保证矿山生产能力的前提。     

美国的城市化进程与现代城市规划联系的解读

回顾了美国城市化的独特发展历程和美国现代城市规划历史,并就二者之间的相互关系进行了探讨,以期对处于转型期的中国城市化发展有所启示和借鉴.     

Similarly traded securities: Greek common vs. preferred stock

This paper examines the price spread between voting (common) and non‐voting (preferred) stocks during the period 1990–95 for a sample of 55 Greek companies. Because in Greece preferred stocks are not essentially different from common stocks, a number of hypotheses were tested to explain the observed differences. The data reveal an average spread of 27.5% for the entire period which, however, varies across years considerably. In cross‐sectional regressions it was found that the volatility of common stock returns, the liquidity of common shares relative to preferred shares, the ownership concentration, and the minimum dividend yield guaranteed to preferred stockholders explain a significant portion of the spread.     

VERTICAL DIFFERENTIATION AND THE DISTRIBUTION OF INCOME

The paper analyses the effects of income concentration on the behaviour of a duopoly with vertical product differentiation and uncovered market. By using a trapezoid distribution, we solve explicitly for market equilibrium as a function of a mean preserving spread of the income distribution. We show that overall more concentrated incomes imply stronger product differentiation, as the presence of a large share of middle‐income consumers stimulates a price competition, whose effects are dampened through an enlargement of the quality spread. While the high‐quality advantage and market coverage increase unambiguously in the degree of income concentration, the behaviour of prices is non‐monotone in the distribution parameter.