一种基于高动态无人机群的TDMA时隙调度策略

为了满足高动态无人机群自组网在网络拓扑频繁变化下快速传输高优先级业务的需求,提出一种基于TDMA协议的动态优先级时隙分配算法。根据节点优先级级别,在TDMA协议框架下提出面向不同业务需求的动态时隙分配算法,采用位向量（BOV）间接确认法实现节点时隙分配;并通过多维度调整策略,综合业务优先级、邻居节点数量、邻居节点变化率和等待时间多个维度确定节点优先级,均衡不同优先级节点对不同数量时隙的申请;最后通过仿真实验对调度策略进行了验证。结果表明,提出的动态优先级时隙分配算法（DP-TDMA）在拓扑频繁变化时可以动态申请、快速分配不同数量的业务时隙,满足对多种业务传输需求;在一定程度上降低了高动态下网络拓扑变化的影响,提高了协议的公平性与稳定性,保证了高优先级信息快速传输,提高了网络的吞吐量。所设计的DP-TDMA算法可应用在高动态无人机群自组网场景中,为网络时隙资源分配提供参考。     

基于改进Bernsen算法的图像二值化研究

针对传统Bernsen算法在实际应用中问题,提出一种改进的新算法。该算法经过对图像进行灰度处理、高斯平滑滤波处理后,计算滤波后阈值,使平滑前后的阈值起不同作用,实现对图像的二值化处理。经验证,该算法不仅适合解决光照不均问题,同时对图像细节有更多保留,优于传统的Bernsen算法。     

美国成品油管道管输能力分配机制及其启示

以用户分类模式、长期托运方及新托运方管输能力分配机制为着眼点,以美国巴克艾伙伴公司和科洛尼尔管道公司为例,详细剖析美国成品油管道的管输能力分配机制.中国成品油管道的公平开放尚处于初期阶段,在深化成品油管道市场化进程中,首先应保证油气设施信息的公开和透明,制订标准的公平开放制度,而后根据中国油气市场行业实际情况逐步细化开放机制.借鉴美国成品油管道管输能力分配机制,对于中国成品油管输能力分配机制,建议:制订全国统一的成品油管网准入制度;搭建统一的管输能力交易平台;考虑地区差异,在统一按历史运输量进行用户分类的模式下,不同地区可根据具体情况对用户分类的具体阈值进行一定程度调整;在管道发生拥塞时,针对长期托运方采取基于历史运输量按比例进行分配的方式;新托运方的管输能力分配采取抽签的方式;监管体系透明化.     

MIMO通信系统下行链路预编码仿真研究

MIMO无线蜂窝通信系统是一种在同一时域和频域中向多个用户提供传输的系统。多用户MIMO技术利用无线通信系统中用户的独立性来增加整个系统的通信性能,从而实现多用户分集和复用。针对单天线用户的线性预编码和针对多天线用户的线性预编码,对联合迫零、迫零和最小均方误差预编码算法进行了仿真和性能对比。对实际通信系统设计具有指导意义。     

区际大气污染物排放权初始分配研究

本文以区际污染物传输决定的区际非合作博弈为研究对象， 依据最优补偿方法和区域浓度上限约束条件， 构建区际大气污染物排放权初始分配模型， 并针对处于不同工业化阶段的区域体系分别求解相应的纳什均衡解和最优排污权初始分配方案， 选取样本进行实证分析。 研究发现， 工业化初期， 各区域完全按照自身无监管排污量的一半申报初始排污权， 无需考虑区域间的相互传输。 工业化中前期， 超前发展的中心区的最优申报量无法达到最优补偿条件， 其值是上限浓度的传出量与承载量之和， 外围区域的最优申报量为其最优补偿结果。 工业化中后期， 区域体系的最优申报量均无法达到最优补偿条件， 此时必然出现最优批复量赤字区， 工业化中期和工业化后期区域间污染传输冲突严重。     

有线电视光缆传输系统指标的分析与设计

介绍了有线电视网中ＡＭ 光缆干线传输综合指标的分析与设计。由于ＤＦＢ激光器间的非线性有较大差异,故引入了光链路这一参数。当把这一参数引入有线电视光缆干线设计时,可根据有线电视光缆系统不同传输距离、光接点的分配指标和光缆干线传输系统的实际情况,计算光链路损耗,以确定光端设备的选型,从而进一步确定光缆干线传输系统的设计,使得有线电视总系统指标给以保证     

矿厂财务科三条线会计核算方式的研究

一、矿厂财务科三条线核算方式的种类 1.整体分配核算法。所谓整体分配核算法,就是矿厂财务科保持“三条线”划分前矿厂会计主体整体核算现状,然后按“三条线”划分后的各核算点资产、权益数额对财务科各期整体核算数据进行分配从而在会计报表上相应确定各核算点财务状况和经营成果数额的一种核算方法。原煤炭部1996年推行“三条线”管理和核算办法时各企业基本采用了这种核算方式。 2.整分平行核算法。所谓整分平行核算法,是指矿厂财务科保持“三条线”划分前矿厂整体核算现状不变,     

基于变邻域搜索算法的物流配送系统集成优化研究

本文针对物流配送系统集成优化问题,考虑取货和送货两种业务的配送情形下仓库和车辆的容量上限约束,构建包括仓库的开放成本、配送成本以及容量溢出成本的非线性混合整数优化模型,设计变邻域搜索启发式算法对模型进行求解。算法通过泰森多边形确定位置上的初始订单分配,再通过扫描半径及消费者数据结构标识实现邻域搜索,改进算法对解决方案进行迭代更新,完成优化求解。最后通过对辽宁宅急送取／送一体化物流配送案例进行数值分析,验证算法可行性和有效性。     

绿盟科技安全知识系列介绍之六

很多网络协议使用明文方式进行数据的传输甚至包括用户认证信息，兀甲、TELNET、POP3、SMTP等协议基本上就是采用明文传输用户名及口令的认证方式，如果黑客居于特定的网络位置可以使用报文嗅探程序窃听到服务器与客户端之间的网络通讯。那么他就能不费力气地收集到用户口令，非法地获取服务的访问权限。对于那些只对认证信息使用可逆算法做简单编码的协议，在网络通信过程中暴露认证信息的风险同样存在。     

基于光子计数探测器的CT系统在蒙特卡罗模拟平台的实现

为了解决利用Matlab,C++等软件对投影图像、重建算法的模拟无法真实反映CT系统的成像过程的问题,在研究模拟理论的基础上,首先利用Geant4和Gate数据包搭建蒙特卡罗模拟平台;然后通过光子计数探测器模拟多能谱CT成像,同时分析在不同标准下的阈值划分对重建图像的影响,利用光子计数探测器同时扫描出多个不同能段下的投影图像,并对比出各个能段下的投影效果;其次,根据不同能段的划分,选取每个能段的360度下的投影数据,利用FBP算法重建投影切片图像;最后,对所得到的切片图像进行材料区分,得到硫和铝的衰减系数曲线。实验结果表明,模拟方法对光子计数探测器的成像过程做出了模拟,得到了较好的模拟图像,并给出了相关阈值的划分依据,可为其他CT成像研究提供参考。     

Comparing FTTH access networks based on P2P and PMP fibre topologies

There is an ongoing discussion in the market which Next Generation Access (NGA) architecture best suits future needs and which investment and cost differences exist. The discussion can be subsumed as P2P vs. GPON, which is somewhat misleading as this article reveals. The discussion is driven by the fact that the high capital cost and the long asset life time of fibre mean that the technology choices made today will dominate the opportunities for telecommunication business of all market players, incumbents, competitors, content providers and business and residential users for many years in the future.The paper analyzes the cost and other differences between Fibre-to-the-Home (FTTH) access network architectures and their related different wholesale approaches by using the well-known and understood steady state approach applied in other NGA analyses in the past. In addition to the steady state analysis a dynamic cost evaluation is included taking into account the different investment behaviour of the FTTH architectures over time. The results describe investment and cost differences between architectures, incumbents and wholesale based competitive operators. The analysis has been performed for different geotypes (clusters) of decreasing population density in a representative European settlement structure.     

Indigenous peoples’ nutrition transition in a right to food perspective

In indigenous communities the nutrition transition characterized by a rapid westernization of diet and lifestyle is associated with rising prevalence of chronic disease. Field work and literature reviews from two different policy environments, Argentina (Jujuy) and Canada (Nunavut), identified factors that add to indigenous peoples’ disease risk. The analytical framework was the emerging human right to adequate food approach to policies and programmes. Indigenous peoples’ chronic disease risk tends to increase as a result of government policies that infringe on indigenous peoples’ livelihoods and territories, undermining their economic system, values and solidarity networks. Policies intended to increase food security, including food aid, may also fuel the nutrition transition. There is a need to explore further the connection between well-intended policies towards indigenous peoples and the development of chronic diseases, and to broaden the understanding of the role that different forms of discrimination play in the westernization of their lifestyles, values and food habits. Food policies that take due account of indigenous peoples’ human rights, including their right to enjoy their culture, may counteract the growth of chronic disease in these communities.     

A strategic skill based model of supplier integration and its effect on supply management performance

Supplier integration is a tool to help organizations gain competitive advantage. Strategic supply management skills and the supply management function's perceived status are hypothesized as antecedents to supplier integration leading to supply management performance. The sample for this study includes 152 executive level supply management professionals. The empirical results suggest that strategic skills and perceived status are essential antecedents to supplier integration and subsequent performance. Further, the relationship between strategic skills and performance is mediated by supplier integration. Results of a dominance analysis also suggest which strategic skills are most likely to explain status integration, and performance. These findings have significant implications for supply management theory and practice.     

面向对象的程序设计

用Ｃ＋ ＋ 语言阐述面向对象程序设计中封装和继承的概念以及在实际中怎样运用这些概念提高程序设计水平。     

Cost allocation of WCDMA and wholesale pricing for mVoIP and data services

This study estimates cost-based prices for wholesale voice and data services provided to 3G (WCDMA) MVNOs according to their distinct types. For estimation, 3G MVNOs are classified into different types, and the overall cost of WCDMA facilities are separated into voice and data components based on their subscriber rates, actual traffic rates, as well as efficiency consideration of traffic rates. The study then calculates cost-based wholesale prices of voice and data services for each of the 3G MVNO types. The result of this study shows that a cost-plus pricing scheme can help achieve the policy goals of the regulator, namely, lowering telecommunications tariffs and facilitating the introduction of new convergent-type services, far more effectively than the current retail-minus pricing scheme. The findings of this study may assist firms in developing business models based on 3G networks and telecom regulators in designing policies related to interconnection, mVoIP, prepaid calls, wholesale services, and network neutrality.     

Collectivism,individualism, and outgroup cooperation in a segmented China

A consistent theme in cross-cultural management research is that collectivists are more cooperative than individualists. We use Hofstede's measure for individualism–collectivism and combine it with an experimental measure of cooperation to test this relationship in China. In contrast to the established paradigm, we find that groups with higher individualistic scores are more cooperative than those groups with higher collectivistic scores. We attribute these results to groups being composed of outgroup members. In addition, we find that subjects from the more developed coastal area are more individualistic and cooperative than are subjects from inland China.

应用CGI技术创建CAI网页计数器

:CGI( Common Gateway Interface)是应用程序与 Web服务器交互的一个标准接口 ,利用该技术可以实现 HTML不具备的交互式主页功能。本文将通过“教育窗”主页的访问 (点击 )计算器的开发应用实例 ,提出了两种使用 CGI技术实现点击计数的方案     

钻井现场H2S气体的探测及防护

在钻井生产过程中，实施HSE管理体系，预防和控制H2S，保护每一位员工不受H2S气体危害，是钻井生产过程中HSE工作的重要一环。阐述了有害气体H2S的物理特性、毒性标准，介绍了几种常用的H2S气体探测器，以及具体操作方法。     

电子产品的电磁兼容性设计

首先介绍电磁兼容性的基本概念与研究领域,然后重点阐述电子产品的电磁兼容性设计与测量。     

SPYRO在烯烃原料生产方案测算中的应用

文章对SPYRO裂解模拟软件在石化企业烯烃生产原料优化方案测算中的应用进行了比较深度的概括分析.结合该软件在上海石化的实际应用,认为在劣质化原油加工份额不断增加的趋势下,SPYRO裂解模拟软件有助于石化企业在烯烃生产原料优化选择、生产计划合理安排、原油加工生产效益比较等方面为企业相关决策者提供有效地帮助.