新丝绸之路经济带建设背景下西安纺织城再生动力初探

在国家提出新丝绸之路经济带建设的宏观战略背景下,西安纺织城作为中国西部传统的纺织工业基地面临难得的复兴机遇。论文以纺织城由繁荣到衰败的过去为镜,以现状存在的现实问题为突破口,探索在重大机遇期,纺织城地区的再生机制。论文分别从政策动因、文化社会动因、区域发展动因、功能动因四个方面进行分析,通过对四个动因的内在关系的判断,探索如何以这些再生的核心动因为基础构建良性的再生机制,以期促使西安纺织城实现可持续的全面再生。     

嘉兴地区中小河流河道整治工程地质勘察技术探讨

近几年,嘉兴市中小河流整治工作如火如荼地展开。那么,如何提高河道的工程地质勘察技术水平呢？本文概述了嘉兴地区中小河流河道整治工程的现状,对嘉兴市河道整治工程地质勘察过程中的一些技术问题进行了分析和探讨。     

欠发达区域房地产业必须关注的问题

房地产业作为和经济发展直接相关的产业,在确立产业地位时,必须以当地经济发展情况而定,尤其是经济欠发达地区,要根据房地产业政策调整,从根本上促进就业与产业发展。本文就我国欠发达区域的房地产业,对相关问题进行了简要地探究。     

严寒地区乡村声景研究

声景有赖于人们在特定环境中对各种声音的评价,乡村声景的宁静特质为“聆听”提供了更多体验空间.基于声音与听者的关系,采用实地调查、声漫步、访谈问卷等方法,对环境声谱进行了案例分析,对主观数据的统计分析研究表明:随着年龄增长,村民对乡村环境常被感知到的声音声舒适评价先增高后降低;不同地区村民对交通声的评价无显著差异性:乡村人群对乡村环境中出现较多的交通声、家畜鸣叫声的声喜好与城市人群具有显著差异.     

浅谈寒冷地区建筑遮阳设计思路

建筑遮阳可以有效地改善室内的光热环境,达到建筑节能的需求。本文从建筑师的角度出发,通过对寒冷地区建筑遮阳的现状进行分析,探讨了寒冷地区建筑遮阳设计思路,包括整体设计的设计理念、寒冷地区的气候环境特点和历史文化对遮阳设计的影响、寒冷地区建筑遮阳的适宜材料和适宜技术的选择,以期为寒冷地区的建筑遮阳设计提供新的方向。     

基于扫描区间表示的不规则多边形快速定位算法及应用

不规则多边形定位算法是排料算法的重要组成部分,其效率对排料算法的性能有重要影响。基于扫描区间表示的不规则多边形定位算法因能适应任意复杂多边形而被广泛采用,但它存在计算量大的不足。通过深入研究基于扫描区间表示的多边形定位算法,该文从两个方面对其方法进行改进：首先提出候选平移位置矩阵的概念,进而实现定位扫描算法;然后通过最大跨度比较法快速排除一些不可能的行,从而通过减少定位扫描算法的调用次数进一步加速。该算法已应用于自主开发服装排料软件,多个实际衣片数据的测试结果证明了该文算法的有效性和高效性。     

分散固相萃取-高效液相色谱-串联质谱快速测定鸡肉中盐霉素残留

建立了分散固相萃取-超高效色谱-电喷雾串联质谱快速测定鸡肉中盐霉素残留的方法。样品经乙腈提取后,采用QuEChERS方法净化,氮吹转换溶剂后,采用Acquity BEH C18柱进行分离,0.3%甲酸水溶液-甲醇体系为流动相,梯度洗脱,电喷雾质谱正离子多反应监测模式测定,外标法定量。结果表明,在优化的条件下对样品进行分析检测,盐霉素的检出限为0.03μg·kg-1,添加水平为5.5~31.4μg·kg-1时,加标回收率为78.2-97.8%,RSD<2.0%(n=6),在0.630~25.2μg·L-1质量浓度范围内呈良好线性,相关系数R2>0.9989。该方法前处理步骤简单,具有较高灵敏度,可用于大批量样品的快速筛查检测。     

Brain segmentation in magnetic resonance human head scans using multi-seeded region growing

This paper presents a skull stripping method to segment the brain from MRI human head scans using multi-seeded region growing technique. The proposed method has two stages. In Stage-1, the brain in the middle slice is segmented, the brains in the remaining slices are segmented in Stage-2. In each stage, the proposed method is required to identify the rough brain mask. The fine brain region in the rough brain mask is segmented using multi-seeded region growing approach. The proposed method uses multiple seed points which are selected automatically based on the intensity profile of grey matter (GM), white matter (WM) and cerebrospinal fluid (CSF) of the brain image. The proposed brain segmentation method using multi-seeded region growing (BSMRG) was validated using 100 volumes of T1, T2 and PD-weighted MR brain images obtained from Internet Brain Segmentation Repository (IBSR), LONI and Whole Brain Atlas (WBA). The best Dice (D) value of 0·971 and Jaccard (J) value of 0·944 were recorded by the proposed BSMRG method on IBSR dataset. For LONI dataset, the best values of D?=?0·979 and J?=?0·960 were obtained for the sagittal oriented images by the proposed method. The performance consistency of the proposed method was tested on the brain images of all types and orientation and have and produced better and stable results than the existing methods Brain Extraction Tool (BET), Brain Surface Extraction (BSE), Watershed Algorithm (WAT), Hybrid Watershed Algorithm (HWA) and Skull Stripping using Graph Cuts (GCUT).     

两相区保温时间对QLT处理9Ni钢组织及性能的影响

将淬火态9Ni钢加热至670℃保温不同时间后水冷并回火.然后采用XRD法测定了实验钢中的逆转变奥氏体含量,进而分析了两相区保温时间对最终组织及性能的影响.结果表明:两相区保温时间为5 min时,其淬火组织特征与QT工艺较为接近;保温时间在10～30 min时,获得的组织与QT淬火后的组织产生明显的差异,组织中的大角度晶界显著增加,促进了回火过程中逆转变奥氏体的形成及钢低温韧性的改善;保温超过30 min后两相区淬火的特征逐渐减弱,钢的组织和性能再次趋近于QT处理,但当两相区保温时间更长时钢的低温韧性略有增加,这可能是由于钢中Ni元素的分布更加不均匀,促进了富Ni区形成更加稳定的逆转变奥氏体.     

Analysis of capacity and coverage region for Rayleigh fading MIMO relay channel

In this paper, we consider Rayleigh fading MIMO relay channel with channel state information at the receivers. First, we extend the previously obtained results for the ergodic capacity of uncorrelated and semi‐correlated MIMO channels and derive closed‐form expressions for the capacity bounds of MIMO relay channel. Next, we study this channel from a new point of view, maximizing coverage region for a desired transmission rate, and investigate the optimal relay location in the sense of maximizing coverage region. However, in order to overcome the mathematical complexity in desired transmission rate analysis, because of the randomness of the multiple antenna channel matrices, we evaluate this rate by using an existing exact formula and also by an approximation we find in the high signal‐to‐noise ratio regime. Numerical results show a perfect match between the Monte Carlo simulations and the obtained analytical closed‐form expressions and also confirm the effectiveness of our approach in cooperative vehicular communication for determining optimal relay location at which the coverage region is maximum. Copyright © 2013 John Wiley & Sons, Ltd.