汽车维修配件 全球统一编码与标识简介

汽车配件与维修服务全球统一编码与标识是汽车维修、流通企业及汽车配件产品的唯一“身份证”。配件产品的唯一编码在全球贸易与信息交换及共享中是唯一的辨识依据,是增强供应链管理的有效手段,能有效提升供应链管理水平。     

医用耗材分类编码工作会在京召开

11月24日,中国医学装备协会和中国物品编码中心在京联合召开医用耗材分类编码工作会。来自食药监总局医疗器械标准管理中心、北医三院的专家及企业代表参加了本次会议。     

Optimal binary codes and binary construction of quantum codes

This paper discusses optimal binary codes and pure binary quantum codes created using Steane construction. First, a local search algorithm for a special subclass of quasi-cyclic codes is proposed, then five binary quasi-cyclic codes are built. Second, three classical construction methods are generalized for new codes from old such that they are suitable for constructing binary self-orthogonal codes, and 62 binary codes and six subcode chains of obtained self-orthogonal codes are designed. Third, six pure binary quantum codes are constructed from the code pairs obtained through Steane construction. There are 66 good binary codes that include 12 optimal linear codes, 45 known optimal linear codes, and nine known optimal self-orthogonal codes. The six pure binary quantum codes all achieve the performance of their additive counterparts constructed by quaternary construction and thus are known optimal codes.     

信息的编码：四位二进制编码

主持人手记：本专栏主要介绍信息技术实验在基础教育信息技术课当中的典型案例,并期望这些案例能够促进信息技术课程学科合法性的提升、丰富信息技术课的教学内容、拓展信息技术教师的课程设计视野。对此栏目有任何好的主意或建议,请发送稿件至towujunjie@163.com（主持人）或tougao1@chinaitedu.cn（杂志社）。     

The design and analysis of unequal error protection fountain coding for multiple source networks over binary erasure channels

A novel network model of multiple source fountain coding is developed and a novel class of generic multiple source fountain codes with unequal error protection(UEP)property is proposed.The And–Or tree analysis technique is generalized to analyze the asymptotic performance of the proposed codes and a joint optimization method employing both linear and nonlinear programs is developed to optimize the degree distributions.Furthermore,we propose three basic methods to achieve UEP property and the performance of each method is discussed.We employ these analytical results and optimization method to design and discuss several UEP codes with two and four sources for different application scenarios.Simulation results verify that the proposed codes can be applied to the networks with any number of sources and can provide strong UEP property in various ways based on the proposed three basic methods.     

化学工程中多目标遗传算法的应用

多目标遗传算法(MOGA)是在遗传算法的基础上发展起来的,它可以进行多个目标之间直接权衡.介绍了多目标遗传算法的概念及发展历程,重点介绍了非劣排序遗传算法(NSGA)和NSGA-Ⅱ,以及多目标遗传算法和过程模拟器结合在化学工程中的应用情况.     

利用Hausdorff距离的快速人耳检测

为有效解决人耳检测中的遮挡和光照不均等问题,结合Hausdorff距离的模糊匹配的特点和较强的抗干扰能力,提出基于Hausdorff距离的人耳检测算法.算法首先用肤色模型检测出人脸区域,然后用canny算子提取边缘,并进行距离变换,再构造多分辨率金字塔模型,在不同分辨率层上采用不同的匹配策略进行Hausdorff距离匹配.算法采用多分辨率方法显著提高检测速度,采用部分Hausdorff距离提高它的抗干扰能力.仿真实验结果取得95%的正确率,并且对遮挡和光照不均具有较强的鲁棒性.     

一种使用小波矩的飞行器目标识别方法

为了在自动识别中提高分类准确率,利用小波的多分辨特性对飞行器图像进行特征提取,并对图像进行径向小波变换,得到可分辨的小波矩.为保证数字图像从笛卡尔坐标系变换到极坐标系的精度,将原图像扩大64倍,并使用三次B样条小波矩、Haar小波矩和Zernike矩分别提取两组图像的特征向量,得到的分离度标准差由使用Zernike矩的0.584提高到使用三次B样条小波矩的0.158.表明三次B样条小波矩可以有效提高分类准确率.     

单纯形法中确定主元素的两个新法则

给出了单纯形法中确定主元素的两个新法则,即"按使目标函数值增加得最多的原则确定主元素"和"按使目标函数值增加得最快的原则确定主元素",并以实例说明了应用这两个法则来确定主元素较应用"最大口法则"来确定主元素.具有迭代次数更少、收敛速度更快的特点.     

基于SWMM与NSGA-Ⅱ耦合的城区雨水泵站多目标优化调控

针对城区复杂水系统中雨水泵站的调控系统性弱和优化时效性慢的问题,将SWMM的水量水质过程模拟与NSGA-Ⅱ的快速非支配排序进行深度耦合,从减缓城区内涝、控制面源污染负荷输出与减低耗电量的角度,建立了多线程并行计算和带有决策者偏好的城区雨水泵站多目标优化调控模型。对天津空港经济区的雨水泵站优化调度进行实例研究,结果表明,与常规调度方式相比,在典型设计降水情景下,该优化模型在不显著增加节点积水累计时间的前提下,减少输出了1383.34 kg的污染负荷,节约了621.92 kW·h电能,求解速率可提升至单线程串行计算的4.2倍。该优化方案充分利用了泵站调蓄池的库容缓冲和水质稀释作用,减缓了场次降水对于城区水环境的瞬时冲击影响,降低了运行成本。