双肌臀大约克猪选育与杂交利用的初步研究

描述了滑刃线虫属（Aphelenchoides Fischer,1894)的2个国内新记录种：游泳滑刃线虫(Aphelenchoides hechaleos)和内卷滑刃线虫(A.involutus)。游泳滑刃线虫采自辽宁省盖州市熊岳镇莴苣(Lactuca sativa)的根际土壤中,它与近似种拟游泳滑刃线虫(A.paranechaleos)的主要区别是雌虫尾较长,尾的形状是腹面凸（而拟游泳滑刃线虫的尾较短,尾的形状是背面凸,腹面凹）,雄虫交合刺背杆的弯曲程度较小。内卷滑刃线虫采自辽宁省凌海市苍耳(Xanthium sibiricum)及山东济南大花金鸡菊(Coreopsis grandiflora)的根际土壤中,它与近似种A.jacobi的主要区别是雌虫尾向腹面弯曲程度较大,尾后部呈钩状,尾较长。     

基于测量的接纳控制研究

与传统的接纳控制算法相比,基于测量的纳控制有诸多优点,首先它无需知识应用的流量模型,其次它能动态适应网络的负载变化,提高网络资源的利用率。文中分析了基于测量的接纳控制的基本思想,并在此基础上提出和实现了一种自适应的接纳控制算法（Adaptive Measurement-Based Admission Control,AMBAC).作者通过实验对该算法进行了验证,发现在系统资源利用率（或接纳能力）接近的情况下,与传统的（固定时间窗口的）,MBAC相比,AMBAC能达到更低的平均分组丢失率。     

The time required for recovery from mixing stress in young bulls and the prevention of dark cutting beef

Two trials were conducted in which a total of twenty-eight Friesian bulls (12 months old) were slaughtered 0, 1, 2, 4, 7, 9 or 10 days after they had been mixed with unfamiliar animals overnight. The resulting behavioural interactions and associated physical activity led to large rises in plasma creatine phosphokinase (CPK) activity and free fatty acid (FFA) concentration and a decrease in plasma lactate. In the second trial the relative number of interactions engaged in by each animal was estimated. Bulls which exhibited the most interactions had the highest levels of plasma CPK and FFA after mixing. Liver and muscle glycogen were depleted by mixing. Animals killed on days 0 and 1 after mixing had low concentrations of liver glycogen compared with animals allowed longer to recover. Concentrations of glycogen in the M. longissimus dorsi (LD) had recovered by day 4 and in the M. psoas by day 2. Muscle glycogen concentrations were reflected in the ultimate pH (pHu) of the meat. All animals killed immediately after mixing produced carcasses with pHu>6. in the LD. By the second day of recovery muscle glycogen stores had been repleted sufficiently so that all animals had muscles with pHu<6. However, the LD from these animals was still very slightly darker than those killed after 7 or more days of recovery although this was probably not commercially significant. It was concluded that, if young bulls from separate rearing groups are mixed before slaughter, either on the farm or during lairage, then they require resting with food for at least 48 h before being killed to ensure that no carcasses are produced with high pHu in the musculature.     

The usability of digestate in organic farming

As organic farming prohibits the use of synthetic fertilisers, animal slurries and manures must be used. Digestate offers an alternative to these and this study reports on three experiments conducted to determine its usability in terms of: (1) the effect on earthworm populations, (2) its fertilising effects on Italian Ryegrass and wild Creeping Thistle, and (3) the suppression effects digestate has on weed emergence. The results for digestate application to field plots were intermediate between slurry and no treatment for earthworm attraction and wild thistle suppression. In glasshouse trials it led to increased ryegrass growth compared with undigested slurry. Analysis showed that the digestate had improved nitrogen availability, leading to increased plant growth, but a reduced organic matter content compared with the slurry, leading to a positive though less beneficial impact on the earthworms. Digestate therefore provides a suitable fertiliser for organic farming. This suitability could be improved by drying or separation to increase the OM content making its properties closer to those of slurry whilst still retaining the higher content of plant available nitrogen.     

一种跳频信号动态检测方法

基于构造型神经网络运算复杂度低、构造直观方便、学习速度快、可解释性强的特点,提出一种跳频信号动态检测方法.首先从滑动窗口的数据流模型入手,采用适合增量学习的覆盖算法动态聚类,聚合相似度大的样本,分离相似度小的样本,降低了聚类复杂度,并减轻了噪声的影响,实现了覆盖簇的动态维护.然后在不同的覆盖簇中提取信号数据概要,构造数据结构数组,运用时频关联方法,排除数组中的定频信号、突发信号、随机噪声信号等,分离出了其中的跳频信号,实现了跳频信号的动态检测.实验结果表明该方法能快速、准确地动态检测跳频信号.     

基于涡轮蜗杆效率的研究及控制系统仿真

设计了一套基于涡轮蜗杆的性能试验台,通过一系列实验准确测量出涡轮蜗杆的传动效率。并在此基础上建立控制系统数学模型,对控制系统进行仿真。     

X射线线扫描安全检查设备实时信号处理

针对X射线在成像过程中存在的非均匀性，利用两点校正法设计了用于X射线安全检查设备的增益和偏移补偿电路；完成了线扫描X射线安全检查设备的数据信号处理硬件模块，给出了电路结构框图；电路采用DSP＋CPLD的结构，在模拟部分和数字部分两次校正，得到了校正前后的处理结果，实现了工程应用。     

基于GIS的城市管网管理系统的设计与实现

本文介绍了采用MapX开发城市管网信息系统的具体过程,并对系统的设计原则、结构设计及功能设计等方面的内容进行了深入分析;为城市规划及管理部门提供了科学管理、科学建设城市的决策依据。     

图片演示稿，PowerPoint快速造

当要在PowerPoint制作图片数很多的图片演示文稿时，如果采用一张张地插入，操作麻烦且易出错，而咱们借助PowerPoint2003中的“相册”功能便可快速完成。