不同游戏方式下的暴力网络游戏对大学生攻击性的影响

目的:探讨不同游戏方式下的暴力网络游戏对不同攻击性特质大学生攻击性的影响。方法:采用攻击性特质问卷、词汇决策任务和竞争反应时任务对60名大学生进行问卷和实验研究。结果:在不同游戏方式下,被试表现出的攻击性认知和行为存在显著差异(F(2,52)=4.41,P<0.05;F(1,52)=50.06,P<0.001)。高、低攻击性特质者在游戏后的攻击性认知和行为上存在显著差异(F(1,52)=15.25,P<0.001;F(1,52)=82.35,P<0.001)。结论:不同游戏方式下的暴力网络游戏对大学生的攻击性存在不同的影响,相比竞争游戏和单人游戏,合作游戏是一种较好的游戏方式,可以在一定程度减少大学生,特别是高攻击性特质大学生的攻击性认知和行为。此外,暴力网络游戏对大学生攻击性认知和攻击性行为的影响存在一致性。     

Numerical investigation on cooling performance of filter in a pyrotechnic gas generator

As a key part of the pyrotechnic gas generator,the filter not only removes the particulate matter but also cools the hot gas to a safe level.This paper aims to improve the understanding of the basic heat and flow phenomenon in the gas generator.The pyrotechnic gas generator is modelling by a simplified filter structure with fiber arrays.A finite-volume model of the heat and fluid flow is proposed to simulate the detailed multi-dimensional flow and energy conversion behaviors.Several verification results are in good agreement with data in different references.Simulation results demonstrate that the filter can not only absorb heat from the gas but also cause the high intensity enhancement of the heat transfer.The per-formance difference between inline and staggered arrays is also discussed.The findings of the study put a further prediction tool for the understanding and design of the filter system with fibers.     

VRML及其在WEB MIS中的应用

简要介绍了虚拟现实建模语言 ,以及该技术在防险救生这一特殊领域中的应用 ;探讨了基于WEB管理信息系统中VRML的实现以及与数据库的关联 .     

The parallel machine min-max weighted absolute lateness scheduling problem

Given a set of jobs, a processing time and a weight for each job, several parallel and identical machines, and a common due date that is not too early to constrain the scheduling decision, we want to find an optimal job schedule so as to minimize the maximum weighted absolute lateness. We show that this problem is NP-complete even for the single-machine case, and is strongly NP-complete for the general case. We present a polynomial time heuristic for this problem and analyze its worst-case performance. Empirical testing of the heuristic is reported, and the results suggest that the performance is asymptotically optimal as the number of jobs tends to infinity. © 1994 John Wiley & Sons, Inc.     

火炮制退机节制杆稳健优化设计方法研究

合理调整制退机节制杆结构尺寸的变化范围,既可以调整火炮的最大后坐阻力和后坐长度,又能缩小它们的波动范围。为了达到上述目的,建立了能够充分考虑坡膛和膛线对炮膛合力影响的节制杆优化模型。提出了一种不仅可以给出设计变量公差带和优化目标变化范围,还能充分考虑设计变量在公差带内分布情况的现代稳健优化设计方法。最后通过某火炮制退机节制杆的稳健优化设计,实现了对上述方法的验证。     

Two-agent scheduling with linear resource-dependent processing times

This paper considers a two-agent scheduling problem with linear resource-dependent processing times, in which each agent has a set of jobs that compete with that of the other agent for the use of a common processing machine, and each agent aims to minimize the weighted number of its tardy jobs. To meet the due date requirements of the jobs of the two agents, additional amounts of a common resource, which may be in discrete or continuous quantities, can be allocated to the processing of the jobs to compress their processing durations. The actual processing time of a job is a linear function of the amount of the resource allocated to it. The objective is to determine the optimal job sequence and resource allocation strategy so as to minimize the weighted number of tardy jobs of one agent, while keeping the weighted number of tardy jobs of the other agent, and the total resource consumption cost within their respective predetermined limits. It is shown that the problem is -hard in the ordinary sense, and there does not exist a polynomial-time approximation algorithm with performance ratio unless ; however it admits a relaxed fully polynomial time approximation scheme. A proximal bundle algorithm based on Lagrangian relaxation is also presented to solve the problem approximately. To speed up convergence and produce sharp bounds, enhancement strategies including the design of a Tabu search algorithm and integration of a Lagrangian recovery heuristic into the algorithm are devised. Extensive numerical studies are conducted to assess the effectiveness and efficiency of the proposed algorithms.     

适于PCT编码的低内存通用树状多带滤波器组实现

基于常用的多带滤波器组的紧支撑性及FIFO(First-in First-out)缓存技术提出了一种具有低内存需求的通用树状多带滤波器组(Tree-structured Filter Bank,TSrS)的实现方法SBFB.该方法具有两大特点:(1)生成与全局变换法相同的子带系数,但是内存需求大大减小且仅与图像宽度及采用的TSFB相关;(2)在FIFO缓存中直接生成父子树(Parent-children Tree,PCT).基于PCT的编码器可直接对位于缓存中的PCT进行编码,而无须在SBFB与编码器之间引入中间缓存.通过分析TSFB的各分解层中的数据流,给出了样本点与子带系数之间的时序关系,并且使用该关系从数学上严格证明了SBFB的正确性.     

Approximation schemes for single‐machine scheduling with a fixed maintenance activity to minimize the total amount of late work

We consider the problem of scheduling n independent and simultaneously available jobs without preemption on a single machine, where the machine has a fixed maintenance activity. The objective is to find the optimal job sequence to minimize the total amount of late work, where the late work of a job is the amount of processing of the job that is performed after its due date. We first discuss the approximability of the problem. We then develop two pseudo‐polynomial dynamic programming algorithms and a fully polynomial‐time approximation scheme for the problem. Finally, we conduct extensive numerical studies to evaluate the performance of the proposed algorithms. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 172–183, 2016     

稀薄流高超声速飞行器气动加热耦合计算

针对稀薄流域高超声速飞行器的气动加热问题,开展耦合数值计算研究。通过引入牛顿冷却定律,将直接模拟蒙特卡洛数值模拟方法与结构传热计算方法相结合,设计一种可对全机外形进行气动热和结构传热计算的高效松耦合方法,实现飞行器防热层结构材料温度分布特性的数值模拟。在以钝锥外形为例对直接模拟蒙特卡洛数值模拟程序进行验证的基础上,采用该方法对X37B轨道飞行器外形长时加热与结构传热过程进行数值模拟,给出结构温度及热流密度随飞行时间的变化规律。研究结果表明,设计的耦合计算方法能够模拟稀薄流域高超声速飞行器的气动加热及结构传热耦合过程,可为该类飞行器的气动热分析及热防护设计提供技术支持。