一种实用新型三态双参数自动调节阀及控制方法

为满足许多工程的实际需要，本文提出了一种实用新型“三态双参数”自动调节阀及其控制方法，与原先的“双态单参数”自动调节阀相比，它具有更高的性价比，在工程方面有着广阔的应用前景。本文提出的控制，方法，可以采用单片机，也可以采用低成本的分立器件来实现控制系统（前者调整参数，方便控制精度高，后者成本低廉专用性强），以适应不同层次用户的需求。     

Serious games and learning effectiveness: The case of It’s a Deal!

Although the value of serious games in education is undeniable and the potential benefits of using video games as ideal companions to classroom instruction is unquestionable, there is still little consensus on the game features supporting learning effectiveness, the process by which games engage learners, and the types of learning outcomes that can be achieved through game play. Our aim in this discussion is precisely to advance in this direction by providing evidence of some of the factors influencing the learning effectiveness of a serious game called It’s a Deal! This serious game was created for the purpose of teaching intercultural business communication between Spaniards and Britons in business settings in which English is used as the lingua franca. This paper hypothesizes that the immersive, all-embracing and interactive learning environment provided by the video game to its users may contribute to develop and enhance their intercultural communicative competence. The study attempts to answer three main research questions: (a) after playing It’s a Deal!, did the students sampled improve their intercultural awareness, intercultural knowledge and intercultural communicative competence in business English? (b) If they improved their intercultural learning, what are the factors influencing such improvement? And (c) if they did not improve their intercultural learning, what are the factors influencing such failure? The game participants who volunteered to take part in the study were all students of English Studies at the University of Alicante in the academic year 2010-2011. One hundred and six students completed both the pre-test and the post-test questionnaires, and played It’s a Deal! A sample of fifty students was selected randomly for the empirical study. The results obtained in the tests performed were compared and contrasted intra-group, both qualitatively and quantitatively, for the purpose of finding any statistically significant difference that may confirm whether or not there was an improvement in the students’ intercultural communicative competence in business English as a result of the implementation of the It’s a Deal! serious game. Findings of this study demonstrate that the video game is an effective learning tool for the teaching of intercultural communication between Spaniards and Britons in business settings in which English is used as the lingua franca. In particular, whereas the game had a small learning effect on intercultural awareness and a medium learning effect on intercultural knowledge, it had a large learning effect on intercultural communicative competence. The study also documents correlating factors that make serious games effective, since it shows that the learning effectiveness of It’s a Deal! stems from the correct balance of the different dimensions involved in the creation of serious games, specifically instructional content, game dimensions, game cycle, debriefing, perceived educational value, transfer of learnt skills and intrinsic motivation.     

Dynamics in Linear Cournot Duopolies with Two Time Delays

Linear differential duopolies are constructed with continuous time scales, constant coefficients and two types of information delays: fixed and continuously distributed time delays. System dynamics are considered with delays in the diagonal terms. By analyzing the associated characteristic equations, it is found that the stability is lost when the lengths of delays cross some critical values. Then it is shown that the destabilizing effect caused by the fixed delays is stronger than the destabilizing effect of the distributed delays having exponentially-declining weighting function. It is further demonstrated that the strength of the destabilizing effect is reversed if the distributed delay has a bell-shaped weighting function.     

Never Let a Serious Crisis Go to Waste

Right now CEOs and board members are under the microscope. The typical CIO, usually struggling for higher visibility and true C-level status, is now in the enviable position of being just outside the scope of C-level witch hunts. At present, the CIO is a functionary—the plumber-in-chief! Previously, we would have cringed at these characterizations, but when there are water shortages, the plumber has great power. The authors describe the new role CIOs will increasingly find themselves in and how to navigate it.     

基于Conformant Fast-Forward规划系统的析取目标处理方法

将规划系统Conformant Fast-Forward从单目标规划扩展到基于析取目标的不确定规划,设计并实现了新的规划系统Conformant-FF-d.Conformant-FF-d的新功能主要包括:目标状态判断、可达性分析和启发函数.提出一种利用SAT技术进行目标状态判断的高效方法;提出析取目标条件下信念状态的可达性分析方法,有效地删除无法到达目标的信念状态,进而缩小了搜索空间的规模;设计了适用于析取目标的启发函数,有效地指导搜索算法向更有希望到达目标的方向进行.在国际规划竞赛的问题域上对Conformant-FF-d和先进的规划系统POND进行测试和对比分析,实验结果表明:ConformantFF-d的求解效率高而且具有较好的可扩展性.     

带两个不同时延神经网络的稳定性研究

讨论了带两个不同时延且有两个神经元系统的局部稳定性,得到了判定神经网络稳定性的一些准则,这些准则有的是与时延有关,而有的是与时延无关（这种情形也称为“无害时延”）;研究方法对于带不同时延且多个神经元网络的稳定性的研究有重要的指导意义。     

如何应对分布式拒绝服务攻击

DDoS攻击难于防范,但防范DDoS也不是绝对不可行的事情。文章从DDoS的原理入手,详细说明如何检查和防范DDoS(synflood)攻击。到目前为止,进行DDos攻击的防御还是比较困难的,因为这种攻击的特点是利用TCP/IP协议的漏洞,除非不用TCP/IP,才有可能完全抵御DDoS。即使DDoS难于防范,我们也不应该"逆来顺受"。实际上,防范DDoS也是可能的。     

应对高校图书馆读者流失的策略

论述了网络信息时代高校图书馆读者流失的原因,提出了高校应对图书馆读者流失的一些策略,以供参考。     

NBmalloc: Allocating Memory in a Lock-Free Manner

Efficient, scalable memory allocation for multithreaded applications on multiprocessors is a significant goal of recent research. In the distributed computing literature it has been emphasized that lock-based synchronization and concurrency-control may limit the parallelism in multiprocessor systems. Thus, system services that employ such methods can hinder reaching the full potential of these systems. A natural research question is the pertinence and the impact of lock-free concurrency control in key services for multiprocessors, such as in the memory allocation service, which is the theme of this work. We show the design and implementation of NBmalloc, a lock-free memory allocator designed to enhance the parallelism in the system. The architecture of NBmalloc is inspired by Hoard, a well-known concurrent memory allocator, with modular design that preserves scalability and helps avoiding false-sharing and heap-blowup. Within our effort to design appropriate lock-free algorithms for NBmalloc, we propose and show a lock-free implementation of a new data structure, flat-set, supporting conventional “internal” set operations as well as “inter-object” operations, for moving items between flat-sets. The design of NBmalloc also involved a series of other algorithmic problems, which are discussed in the paper. Further, we present the implementation of NBmalloc and a study of its behaviour in a set of multiprocessor systems. The results show that the good properties of Hoard w.r.t. false-sharing and heap-blowup are preserved.     

应对高纪实度时代的摄影

从摄影艺术的角度看,需要不断追求影像的清晰度以及高表现力吗?纪实摄影如何面对现今这个技术高速发展的社会是本文所需要解决的问题。摄影艺术应超脱技术性真实,人所处的时代、阶层、地区,所属的民族,所有的意识形态等种种的不同和它本身所有的特性也决定了摄影本身无法全部挑起背负记录真实历史的重担。所以,一个成功的摄影者完全有必要明白在真实与艺术之间该做出如何的选择,使摄影艺术的美与真完美结合。     

具有两类信息的无线局域网实时介质访问协议

针对工作站到达两类对实时性要求不同的数据帧的应用系统,设计了一种实时的无线局域网介质访问协议。具有实时帧的工作站需要延迟一个较短的帧间隙时间,如果实时帧之间发生了传输冲突,接入点会轮询所有工作站以快速解决冲突。仿真结果表明实时帧比非实时帧经历更短的平均等待时间,并且等待时间具有确定的上限值。     

数字新媒体时代如何应对国外文化渗透

通过介绍数字新媒体的概念和特点,引出网络时代应对国外文化渗透的重要性,介绍应对措施,分别是:对网络讨论要进行深层次挖掘,有关部门要及时进行舆论引导;去伪存真,及时发现"以退为进"的渗透策略;加大正面宣传力度,多方面主动出击,维护我国正面形象;认清"网络水军"的管理者,把握可能的舆论导向;加大整体网民的上网素质;加大新媒体的管理力度。     

关系模型中不确定信息与可能信息的引入与处理

一、引言 传统关系模型下的关系数据库所表示的信息都是确定信息,即元组所描述的实确确实实被包含在关系数据库所定义的现实世界中,即使是含有空值及模糊值的不完全关系数库,元组与相应的数     

处理动态优化问题中控制变量路径约束的方法

目前国际上对动态优化问题中的状态变量路径约束已有一些研究,但专门处理控制变量路径约束的方法却鲜见报道. 本文首先介绍两种分别基于三角函数变换、约束算子截断来处理控制变量路径约束的方法,然后提出一种基于光滑化的二次罚函数方法. 光滑化罚函数方法不仅能够处理控制变量路径约束,而且还能同时处理关于状态变量的路径约束. 最后使用目前流行的控制变量参数化 (Control variable parameterization, CVP)策略对最终获得的、不再含控制变量路径约束的动态优化问题求解. 实例测试一展现了三种方法各自的特点;实例测试二表明了光滑罚函数方法的有效性和优越性.     

Improved SMOTE Algorithm to Deal with Imbalanced Activity Classes in Smart Homes

Neural Processing Letters - Performance of resident-activity-recognition systems is an important measure in the evaluation of smart homes performance. An imbalanced distribution of activity...     

自动加药装置在煤矿矿井水治理中的应用

针对矿井水在提升过程中,流量和水中浊度不断改变。聚合氯化铝(PAC)和聚丙烯酰胺(PAM)的加药量也需不断地改变,人工调节很难满足现场要求的问题,采用了全自动加药装置。矿井水治理采用自动加药装置后,保证了井下除尘用水水质稳定,使净化后的清水浊度稳定在50 NTU以下,完全满足了井下除尘用水的要求;降低了药耗,药剂成本由0.98元/t降到0.44元/t,每年可节省药刑费19.44万元;并且减轻了工人劳动强度,改善了治理水平。     

一个可处理不确定性知识的专家系统开发工具

介绍了用面向对象的可视化语言Ｖｉｓｕａｌ Ｃ＋＋实现的一个可处理不确定性知识的专家系统开发工具ＲＥＳＴＯＯＬ,着重描述了其知识库组织、不精确推理机的实现及推进过程可视化,并给出了一个运行实例。     

数字新媒体时代如何应对国外文化渗透

通过介绍数字新媒体的概念和特点,引出网络时代应对国外文化渗透的重要性,介绍应对措施,分别是：对网络讨论要进行深层次挖掘,有关部门要及时进行舆论引导;去伪存真,及时发现“以退为进”的渗透策略;加大正面宣传力度,多方面主动出击,维护我国正面形象;认清“网络水军”的管理者,把握可能的舆论导向;加大整体网民的上网素质;加大新媒体的管理力度。     

一种应对APT攻击的安全架构:异常发现

威胁是一种对特定系统、组织及其资产造成破坏的潜在因素,反映的是攻击实施者依照其任务需求对被攻击对象长期持续地施以各种形式攻击的过程.面对高级可持续威胁(advanced persistent threat, APT),在其造成严重经济损失之前,现有的安全架构无法协助防御者及时发现威胁的存在.在深入剖析威胁的外延和内涵的基础上,详细探讨了威胁防御模型.提出了一种应对APT攻击的安全防御理论架构:异常发现,以立足解决威胁发现的难题.异常发现作为防御策略和防护部署工作的前提,通过实时多维地发现环境中存在的异常、解读未知威胁、分析攻击实施者的目的,为制定具有针对性的应对策略提供必要的信息.设计并提出了基于异常发现的安全体系技术架构:“慧眼”,通过高、低位协同监测的技术,从APT攻击的源头、途径和终端3个层面监测和发现.