OSGi及其QoS获益驱动动态软件体系结构研究

随着软件领域中移动计算、分布计算和Web Service等技术的迅速发展,软件计算环境变得越来越开放、复杂、多元。如何应对不断变化的计算环境,构建一个自适应的动态软件架构,受到了越来越多的关注。文章首先介绍一个成功的软件系统结构框架实例——Open Service Gateway Initiative(OSGi)。然后,以请求质量QoS为核心,对面向服务的OSGi框架进行扩展,提出了一个动态自适应软件架构解决方案,它以用户QoS属性为目标驱动,通过动态调整软件自身结构,以进一步提高用户期望的服务质量。实验结果证明了该调度框架的有效性。     

Areal differentiation of virtual water for agricultural products and its effect on regional agricultural structure adjustment in China： 1995-2007

With a vast territory, the space-time distribution of water resources is uneven in China. There is a great dif ference in natural conditions and farmland management of agricuttural production in different regions. The areal differentiation of agricultural products virtual water is obvious. Comparison with the agricultural products virtual water from 1995 to 2007 in China shows an increase in the first ten vears and a little decrease in recent years. There has been a tendency of increase all the time in Northeast and Northwest. but a decrease after an increase firstly in other regions. The virtual water offood crops is the maximum which accounts for more than 70% in China. and that of vegetables is in a fast growth. The proportion of agricultural products virtual water to the total water resources in each region has a large difference, showing the imbalance of agricultural water in different regions, which accounts for 50%-90% in Northeast, and 125%-185% in North China. Under the guidance of virtual water strategy, based on the differences of resource endowment, each region should adjust agricultural structure, decide production by water, and select water suitable crops. In water-rich region, agricultural produets of high water consumption should be planted appropriately, which will make full use of the abundant local water resources. In water-shortage region the crop production of high water consumption and low efficiency should be depressed, and that of low water consumption and high efficiency should be supported and increased. It will achieve reasonable disposition of water resources, promote ecological restoration and environmental protection, as welt as ensure food security.     

论大学校园文化建设

优秀的校园文化是创建一流大学的必要条件,一流的大学必有一流的校园文化。大学的校园文化建设要从软硬件两个方面着手,软件方面主要指学校的传统等;硬件方面包括校园的建筑设计、校园景观和美化绿化等物化形态的东西。     

软件开源发展及商业化分析

随着开源日益快速的发展,开源对软件开发越来越重要。该文对欧美开源发展及商业化情况作了简要分析,列出企业开源的主要途径以及开源商业化的模式。同时针对国内的开源状况,分析了未来我国开源发展的几个重要因素,并提出了相应的建议和措施。     

浅谈多媒体与多媒体课件的制作

在现代教学实践中,讲究的是教学的手段和教学的效果,随着科学技术的发展,计算机辅助教学（CAI）越来越得到普及,从而要求老师去改变传统的教学方法,适应现代化教学的需要,其中多媒体课件在教学中的应用就是这方面的一个突出表现。     

虚拟平台中智慧城市信息转移演化博弈分析

在新一代信息技术支撑下的智慧城市中,构建信息化资源共享的虚拟平台成为其信息转移和共享的有效途径。因此文章分析了信息作为生产要素在农业时代、工业时代、信息时代、智慧时代的表现形式及转移虚拟平台构建的必要性。在信息传递主体有限理性的情况下,将演化博弈理论引入到信息转移过程中形成政府与信息主体的收益矩阵,并研究虚拟平台在官管民营模式下,信息转移过程中资源主体和政府的复制动态方程及稳定状态点现实解释。用复制动态相位图表示政府和信息资源主体在转移共享和激励行为比例变化的复制动态关系,探讨四种情况下稳定状态的收敛性与抗扰动性。最后得出结论为不管任何状态下的复制动态关系和稳定性,政府通过调整战略和信息平台中的收益分配比重,既不影响信息主体的积极性,同时又能提高其收益,使博弈双方主体均有能力和动力推动信息转移共享,从而达到帕累托上策均衡。     

仿真技术在电类课程实践教学中的应用

在电类实践课程教学过程中引入仿真软件,可以克服传统实践教学中的一些不足,使教学过程更加方便、灵活、直观,能激发学生的学习兴趣,从而能取得更好的教学效果。通过阐述多种仿真软件在电类课程实践性教学中的应用,说明引入仿真技术有利于提高教学质量,也是电类专业课程教学改革的关键之一。     

The M4 Competition: Results,findings, conclusion and way forward

The M4 competition is the continuation of three previous competitions started more than 45 years ago whose purpose was to learn how to improve forecasting accuracy, and how such learning can be applied to advance the theory and practice of forecasting. The purpose of M4 was to replicate the results of the previous ones and extend them into three directions: First significantly increase the number of series, second include Machine Learning (ML) forecasting methods, and third evaluate both point forecasts and prediction intervals. The five major findings of the M4 Competitions are: 1. Out Of the 17 most accurate methods, 12 were “combinations” of mostly statistical approaches. 2. The biggest surprise was a “hybrid” approach that utilized both statistical and ML features. This method’s average sMAPE was close to 10% more accurate than the combination benchmark used to compare the submitted methods. 3. The second most accurate method was a combination of seven statistical methods and one ML one, with the weights for the averaging being calculated by a ML algorithm that was trained to minimize the forecasting. 4. The two most accurate methods also achieved an amazing success in specifying the 95% prediction intervals correctly. 5. The six pure ML methods performed poorly, with none of them being more accurate than the combination benchmark and only one being more accurate than Naïve2. This paper presents some initial results of M4, its major findings and a logical conclusion. Finally, it outlines what the authors consider to be the way forward for the field of forecasting.     

Identifying changes and trends in Hong Kong outbound tourism

Despite the numerous research endeavors aimed at investigating tourists’ preferences and motivations, it remains very difficult for practitioners to utilize the results of traditional association rule mining methods in tourism management. This research presents a new approach that extends the capability of the association rules technique to contrast targeted association rules with the aim of capturing the changes and trends in outbound tourism. Using datasets collected from five large-scale domestic tourism surveys of Hong Kong residents on outbound pleasure travel, both positive and negative contrasts are identified, thus enabling practitioners and policymakers to make appropriate decisions and develop more appropriate tourism products.     

Migrant networks, language learning and tourism employment

This paper examines the relationship between migrants’ social networks, the processes of language acquisition and tourism employment. Data collected using netnography and interviews are used to identify the strategies that Polish workers in the UK use to develop their language skills. The paper highlights the roles played by co-workers, co-nationals and customers in migrants’ language learning, both in the physical spaces of work and the virtual spaces of internet forums. It also shows how migrant workers exchange knowledge about the use of English during different stages of their migration careers: prior to leaving their country of origin and getting a job, during their employment and after leaving their job. Implications for academic inquiry and human resource management practice are outlined.