Layouts for ocean wave energy farms: Models,properties, and optimization

Renewable energy, such as wave energy, plays a significant role in sustainable energy development. Wave energy represents a large untapped source of energy worldwide and potentially offers a vast source of sustainable energy. We present models and a heuristic algorithm for choosing optimal locations of wave energy conversion (WEC) devices within an array, or wave farm. The location problem can have a significant impact on the total power of the farm due to the interactions among the incident ocean waves and the scattered and radiated waves produced by the WECs. Depending on the nature of the interference (constructive or destructive) among these waves, the wave energy entering multiple devices, and thus the power output of the farm, may be significantly larger or smaller than the energy that would be seen if the devices were operating in isolation. Our algorithm chooses WEC locations to maximize the performance of a wave farm as measured by a well known performance measure called the q-factor, which is the ratio of the power from an array of N WECs to the power from N WECs operating independently, under the point absorber approximation. We prove an analytical optimal solution for the 2-WEC problem and, based on the properties of the 2-WEC solution, we propose an iterative heuristic optimization algorithm for the general problem.     

商业生态系统价值结构、企业角色与战略选择

与强调企业在商业生态系统中如何攫取领导地位的战略观不同,本文把研究重心放在了企业战略如何塑造成功商业生态系统上。首先,本文构建了成功商业生态系统的价值结构模型,为企业的战略选择提供了微观与宏观上的方向与路径。其次,本文讨论了与成功商业生态系统相匹配的企业角色,并结合价值结构模型定义了与企业角色相匹配的战略任务。最后,在此基础上,重点阐述了骨干型企业在如何塑造成功商业生态系统过程中具体的宏观战略选择路径与机制问题。     

论民法上的公共政策——兼论民法规范配置的政策导向

公共政策是为了实现某一特定时期的政治或社会目标而采取紧急措施的准则,是一个开放的不确定性概念。公共政策与公序良俗的核心内容是基本一致的,但公共政策的外延要比公序良俗广。为了限制法官的自由裁量权,对公共政策类型化研究极为必要。为了贯彻和体现民法中不同类型的公共政策,民法设置了不同的规范类型。公共政策的关键要点在于,绝大多数的公共政策都是"有旨向的"。     

同一电子组态原子态g因子的最大值

本文指出了文［１］中的错误，给出了确定同一电子组态原子态ｇ的最大值的普遍方法．     

Study on the Labor Resources Distribution and Optimizing Configuration

This thesis analyzes the change of labor resources distribution in the whole country and the effect of financial crisis on the labor force by use of employment population size,investment scale and the relevant data of GDP scale from different provinces in China.The optimal investment model of labor force is built according to the Marginal Product Elasticity Theory to estimate the quantity of surplus labor force in provinces and cities in China.It also analyzes the effect of investment on the labor force migration according to Capital-Labor Force Flow Model of Thomas B.The study shows that there is no shortage of labor resources in our country;the labor resources distribution in eastern regions is close to the optimization;the largescale surplus labor force still exist in central and western regions;western regions will become the regions with the largest number of surplus labor resources instead of central regions.     

我国农业、农村经济发展历程的经济学思考

建国以后,在我国农业和农村经济曲折的发展过程中,生产力要素配置规律起了决定性的作用。土地改革,农业合作化,八十年代农业经营方式的改革,其效果都因是否遵循生产力要素配置规律而明显不同。回顾农业、农村经济发展的历程,违背生产力要素的配置规律,是造成我国农业长期落后和农村贫困的主要原因。目前,我国的二元社会、经济结构及由此带来的破坏生产力要素配置规律的种种因素仍在起作用。     

Technological change and sociocultural models in China: A case study of train commuters in Beijing

ABSTRACT

China’s mobility turn has created the world’s largest public rail system, contributing extensively to citizens’ economic, social, and spatial mobility. Concurrently, this technological transformation has introduced many opportunities for individuation, which could potentially challenge the social, collectivistic, and Confucian foundations of China’s sociocultural and political ideology. While the notion that ‘mobility produces culture’ is readily accepted, research on train mobility in China is rare. In this study, we use Albert Bandura’s Model of Triadic Reciprocal Causation to conceptualize mobility as agency. We employ Hermeneutic Content Analysis, a mixed methods framework, to study how this rapidly evolving mobility environment connects to the lives of 31 regular train users living in Beijing. Studying agency in China enables us to systematize the sociocultural models within which mobility practices are embedded and how they manifest. We find that our interviewees embed agentive practices in a cultural model that is intertwined with collectivistic aspirations of the country. Technological developments are thus integrated into existing sociocultural models and political expectations, contradicting existing debates on the fracturing impact of disruptive technologies.     

Establishing safety stocks for master production schedules

The basic master production scheduling problem assumes that periodic demands are known with certainty. Uncertainty in the forecasts arc typically accommodated afterwards by adding safety stocks to a schedule. Two popular methods for establishing safety stocks are: (1) the constant cycle service level method; and (2) the constant safety stock method. This paper outlines these methods and then develops a third method which results in optimal safety stocks. The paper includes an experimental investigation aimed at comparing performances of the three safety stock methods. The constant safety stock method is shown to perform within one or two per cent of optimal, while the constant cycle service level method performs worse under most conditions. Shorter lead times, variable order interval lengths, and time-dependent forecast errors all adversely affect the performances of the non-optimal methods. An operations manager could use these results to evaluate the appropriateness of the methods for his master production scheduling environment.     

HSRP技术在网络设计中的应用

HSRP是最为常用的路由器备份技术,本文介绍了HSRP的工作原理及运用,并结合企业的网络设计要求,给出了在C isco 2611XM路由器上实现HSRP的具体配置。     

Windows2003下IIS安全配置与管理

Windows2003下IIS安全配置与管理,是实现WIN2003操作系统和IIS服务器的安全,也是创建Internet网站所必须的设置。