基于复杂供应链库存管理策略的系统动力学研究

在分析了具有不同提前期和加工时间的复杂供应链特点基础上，研究了混合CONWIP／Kanban库存管理思想与同步CONWIP库存管理思想在复杂供应链上的应用。同时借助Vensim建模平台。针对这两种管理思想建立了基于复杂供应链系统的动态仿真模型，并对模拟结果进行了分析。     

Do investors in Green Bond market pay a premium? Global evidence

We examine the pricing difference of Green Bonds (GB) and conventional bonds (CBs) in capital markets worldwide. Credit spread is used to observe whether investors would like to pay a premium for GBs over CBs. This study uses panel data regression with hybrid model to analyse daily observations over the period 2016 to 2017. We employ Option-Adjusted spread (OAS) to measure the credit spreads of bonds while controlling for bond specific, macroeconomic and global factors that influence the spread. With the hybrid model used in the panel data analysis, we were able to capture the fixed-effects of variables in a random effect model. We find that GBs are traded at a premium of 63 basis points (BPS), compared with a comparable corporate bond issue. We find that the green label provides issuers an incentive to raise funds through issuing GBs while providing investors an opportunity to diversify their investments returns. Our findings provide several implications to the major stakeholders driving the GB market to scale up the market to finance the required level of global green investment needs. We stress an urgent need to support the growth of the GB market to achieve sustainable development through mitigating climate change challenges.

Abbreviation GB: Green Bond; CB: Conventional Bond; YS: Yield Spread; BPS: Basis Points; OAS: Option-Adjusted Spread; PCSE: Panels Corrected Standard Errors; CPI: Consumer Price Index; GBPs: Green Bond Principles; CBS: Climate Bond Standard     

Dynamic R&D competition with memory

We consider a differential game of R&D competition and explore the impact of rivalry on the firms' investment behavior over time. Using closed-loop strategies and hence allowing for strategic interactions among rival firms we show that R&D spending by the individual competitor is increased due to competition in the race for priority. This leads us to argue that competitive encounters enhance R&D activities at the same time as increasing efficiency in the race for a technological breakthrough.     

Bioenergy Crop Production in the United States: Potential Quantities, Land Use Changes, and Economic Impacts on the Agricultural Sector

The U.S. Departments of Agriculture and Energyjointly analyzed the economic potential for,and impacts of, large-scale bioenergy cropproduction in the United States. Anagricultural sector model (POLYSYS) wasmodified to include three potential bioenergycrops (switchgrass, hybrid poplar, and willow). At farmgate prices of US $2.44/GJ, anestimated 17 million hectares of bioenergycrops, annually yielding 171 million dry Mg ofbiomass, could potentially be produced at aprofit greater than existing agricultural usesfor the land. The estimate assumes highproductivity management practices are permittedon Conservation Reserve Program lands. Traditional crops prices are estimated toincrease 9 to 14 percent above baseline pricesand farm income increases annually by US $6.0billion above baseline.At farmgate prices of US $1.83/GJ, anestimated 7.9 million hectares of bioenergycrops, annually yielding 55 million dry Mg ofbiomass, could potentially be produced at aprofit greater than existing agricultural usesfor the land. The estimate assumes managementpractices intended to achieve highenvironmental benefits on Conservation ReserveProgram lands. Traditional crops prices areestimated to increase 4 to 9 percent abovebaseline prices and farm income increasesannually by US $2.8 billion above baseline.     

信息网络对企业空间组织的影响

信息网络是信息社会的主要基础设施,本文从信息网络的概念、分类和形状入手,讨论了信息网络对企业区位和劳动空间分工的影响,并举例加以说明,最后对地理学开展新的空间经济发展研究提出了思路.     

Illicit drug markets and economic irregularities

Markets for illicit drugs present an interesting case study for economics, combining non-standard characteristics such as addiction and product illegality. One response has been to argue the generality of economic principles by suggesting that they apply even in the extreme case of markets for addictive substances, e.g., by showing that demand for illicit goods is responsive to price [1] [Reframing health behavior change with behavioral economics. Hillsdale, NJ:Lawrence Earlbaum Associates; 2000. p. 89-111.] and even by modeling addiction as rational [2] [J Political Econ 1988;96:675-700]. This paper sketches examples of an alternative reaction, focusing on idiosyncrasies of drug markets that might plausibly create counter-intuitive effects, including supply curves that slope downward because of enforcement swamping and/or a good serving as the only available store of wealth for its producer, demand reduction programs that increase demand, and consumption by “jugglers” possibly increasing rather than decreasing as prices rise. This analysis yields non-obvious policy recommendations; for example, source country control programs should concentrate on growing regions with a healthy banking sector.     

Hybrid Inflation-Price-Level Targeting in an Economy With Output Persistence

This paper investigates hybrid inflation‐price‐level targeting (HT), employing a Phillips curve with output persistence. By HT we mean that a central bank targets a weighted average of the optimal inflation rate and its corresponding price level. The analysis shows that if output is persistent to some extent, it is desirable to adopt HT because, relative to the case of alternative regimes such as inflation targeting (IT) and price‐level targeting (PT), it will reduce the variability of inflation and thereby social loss. In addition, it is shown that the optimal hybrid‐type target is uniquely determined according to the degree of persistence in output.     

基于混合优化算法的带时间窗的车辆调度问题求解研究

论文建立了带时间窗的车辆调度问题的数学模型，并针对遗传算法在局部搜索能力方面的不足，提出将模拟退火算法与遗传算法相结合，从而构造了求解车辆调度问题的混合优化算法，并进行了实验计算。计算结果表明，用这种混合优化算法求解车辆调度问题，可以在一定程度上用模拟退火算法突跳性克服遗传算法在局部搜索能力方面的不足，从而得到质量较高的解。     

网络经济下企业组织环境的变化与经营模式的变革

网络经济是建立在信息的生产、分配和使用基础之上的经济形态。在网络经济环境下 ,企业经营的组织环境出现了新的变化 ,因而使企业的经营模式发生了从大规模生产到大规模定制 ,从产品经济到服务经济 ,从实体经营到虚拟经营 ,从互相竞争到双赢合作的根本性变革。把握这些新变化并改进我国企业经营的策略 ,有利于企业战略目标的实现。     

知识联盟中的学习障碍研究

知识联盟是企业获取外部知识的重要途径。然而 ,在知识联盟中却蕴含着各种形式的学习障碍 ,制约了知识的有效转移。本文首先从知识、企业和联盟对象三方面分析了联盟中学习障碍的状况及主要来源。