首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   16篇
  免费   1篇
  国内免费   3篇
安全科学   8篇
废物处理   1篇
环保管理   1篇
综合类   4篇
基础理论   2篇
污染及防治   1篇
社会与环境   2篇
灾害及防治   1篇
  2017年   1篇
  2016年   1篇
  2014年   2篇
  2013年   1篇
  2011年   2篇
  2010年   2篇
  2009年   5篇
  2008年   1篇
  2007年   1篇
  2006年   2篇
  2005年   1篇
  2000年   1篇
排序方式: 共有20条查询结果,搜索用时 15 毫秒
1.
设计了基于PXA270 Xscale处理器和多片TMS320DM642 DSP处理器的并行智能视频监控系统,详细介绍了其体系结构的特点,关键模块的硬件组成及工作原理,并通过在该系统上实现运动目标的实时跟踪算法验证了系统的设计性能.验证结果表明,该监控系统具有处理速度快、接口丰富、成本低廉、可重构的特点,适合应用于视觉导航、安全监控等要求高速视频图像处理的场合.  相似文献   
2.
本文比较研究了BP神经网络中的几种常用算法,针对这些不同算法下的BP神经网络进行训练,并得出了各自网络的性能。在此基础上,针对经典BP算法和LM算法进行对比研究,找到LM算法的改进之处。此外,在实际的应用中表明,不仅不同的BP算法对网络的运算速度、泛化能力等有较大的影响,而且BP神经网络对隐含层神经元数目也很敏感。我们希望在BP神经网络的基础上,构建一种合适的天线模型,来应用于天线的分类识别,这将具有很大的现实意义。  相似文献   
3.
ABSTRACT

This work deals with the optimization of an hybrid energy system used to supply an isolated site. The proposed system combines a wind turbine, a photovoltaic panel, a diesel generator and a battery bank to electrify atypical home. An energy cost-effectiveness approach is adopted in accordance with meteorological data, time profile of energy consumption, and the cost of different alternative systems. A variety of performances is obtained through simulations within the Homer Pro environment. The selection of an optimal combination is based on the maximum integration of renewable energy in the suggested system with a minimum of gas emission. According to the obtained results, the overall cost of the selected installation is about 72,900 €, with 0.415€ the unit cost of a kWh electric energy provided with a contribution of renewable energy of around 86%. Simulations show a technical and financial benefits of the different configurations obtained to supply the target site. To control the proposed hybrid energy system, a supervision algorithm is developed and implemented on TMS320F28027 DSP platform. The proposed energy system aims to take advantages of renewable energy sources and shift to conventional sources only when necessary in order to ensure source autonomy and service continuity.  相似文献   
4.
稀有鮈鲫Dmrt基因家族13个成员的克隆与序列分析   总被引:1,自引:0,他引:1  
已经发现果蝇Doublesex、线虫Mab-3、青DMRT1Y/DMY和人类DMRT1等性别决定与分化基因均含有一个具有DNA结合能力的保守基序--DM结构域,对性别决定和性别分化具有调控功能.利用简并PCR,从稀有鲫基因组DNA中克隆了13个具有不同DM结构域的Dmrt基因家族成员.基于DM保守基序,建立了各物种的进化树.结果表明,稀有鲫基因组存在多个Dmrt基因成员,该基因在脊椎动物和非脊椎动物中具有高度保守性,是一种理想的环境内分泌干扰物研究的分子模型,在分子生态毒理学研究中具有很好的应用前景.  相似文献   
5.
黑斑蛙Dmrt1基因的克隆及在不同组织中的表达   总被引:4,自引:0,他引:4  
Dmrt基因家族是新近发现的一个与性别决定相关的基因家族,该家族成员都含有一个新的具有DNA结合能力的保守基序——DM结构域.本文采用简并PCR技术,扩增并克隆了黑斑蛙基因组中的DM结构域,经序列分析,获得了Dmrt家族成员rnDmrt1;进一步根据获得的rnDmrt1序列,设计一对特异引物,采用RT-PCR技术对成蛙不同组织Dmrt1基因的表达进行了研究.结果发现,rnDmrt1只在精巢中特异表达,在卵巢、脑、肝、心、肾及肌肉组织中无表达,显示Dmrt1基因在性别决定和分化中有重要功能. 图4参9  相似文献   
6.
The effects of rice straw addition level on odorous compounds emissions in a pilot-scale organic fraction of municipal solid waste (OFMSW) composting plant were investigated. The cumulative odorous compounds emissions occurred in a descending order of 40.22, 28.71 and 27.83 mg/dry kg of OFMSW for piles with rice straw addition level at ratio of 1:10, 2:10 and 3:10 (mixing ratio of rice straw to OFMSW on a wet basis), respectively. The mixing ratio of rice straw to OFMSW had a statistically significant effect on the reduction of malodorous sulfur compounds emissions, which had no statistically significant effect on the reduction of VFAs, alcohols, aldehydes, ketones, aromatics and ammonia emissions during composting, respectively. The cumulative emissions of malodorous sulfur compounds from piles with the increasing rice straw addition level were 1.17, 1.08 and 0.88 mg/dry kg of OFMSW, respectively. The optimal mixing ratio of rice straw to OFMSW was 1:5. Using this addition level, the cumulative malodorous sulfur compounds emissions based on the organic matter degradation were the lowest during composting of OFMSW.  相似文献   
7.
本文提出了一种基于以太网的视频监控系统的设计方案.采用TMS320DM642为核心处理器,设计了视频采集、显示模块和网络接口模块,开发了H.264压缩算法和流媒体实时传输协议(RTP),并编写了软件,实现了视频图像的编码压缩、本地存储和网络传输.运行结果表明,本系统能够满足实时监控的要求,且压缩效率高,图像质量好.  相似文献   
8.
介绍了无线视频采集传输方案,利用CMOS微型数字图像传感器OV7660采样空间图像,DSP控制器TMs320DM642芯片根据OV7660同步时序控制图像数据采集,并实现基于H.263的实时编码压缩,压缩后的视频流经由基于TCP/IP协议的以太网无线传输到远程监控中心,最后通过上位机处理软件解码还原图像.另外,对压缩后的视频数据还可以通过USB接口进行本地存储.便于校验和查询.采用软硬件相结合的方式,降低了系统开发成本.  相似文献   
9.
A field lysimeter/mini plot experiment was established in a silt loam soil near Lincoln, New Zealand, to investigate the effectiveness of urea fertilizer in fine particle application (FPA), with or without the urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT - “Agrotain”), in decreasing nitrogen (N) losses and improving N uptake efficiency. The five treatments were: control (no N) and 15N-labelled urea, with or without NBPT, applied to lysimeters or mini plots (unlabelled urea), either in granular form to the soil surface or in FPA form (through a spray) at a rate equivalent to 100 kg N ha−1. Gaseous emissions of ammonia (NH3) and nitrous oxide (N2O), nitrate (NO3) leaching, herbage dry-matter (DM) production, N-response efficiency, total N uptake and total recovery of applied 15N in the plant and soil varied with urea application method and with addition of NBPT. Urea with NBPT, applied in granular or FPA form, was more effective than in application without NBPT: N2O emissions were reduced by 7-12%, NH3 emissions by 65-69% and NO3 leaching losses by 36-55% compared with granular urea. Urea alone and with NBPT, applied in FPA form increased herbage DM production by 27% and 38%, respectively. The N response efficiency increased from 10 kg DM kg−1 of applied N with granular urea to 19 kg DM kg−1 with FPA urea and to 23 kg DM kg−1 with FPA urea plus NBPT. Urea applied in FPA form resulted in significantly (P < 0.05) higher 15N recovery in the shoots compared with granular treatments and this was improved further when urea in FPA form was applied with NBPT. These results suggest that applying urea with NBPT in FPA form has potential as a management tool in mitigating N losses, improving N-response efficiency and increasing herbage DM production in intensive grassland systems.  相似文献   
10.
基于DaVinci技术的嵌入式视频监控系统设计   总被引:1,自引:0,他引:1  
针对视频监控系统实时性要求高运算量大的特点,提出了基于DaVinci技术的嵌入式视频监控系统设计方案。方案利用基于DaVinci技术的TMS320DM6467 ARM+DSP双核处理器,提高了系统性能,缩短了开发周期。ARM核植入嵌入式Web服务器,以UDP协议实时传输视频数据,实现控制模块与监控终端之间的通信。DSP内核视频数据编码算法选用H.264,大大提高了数据编码效率。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号