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   6篇
  免费   0篇
化学工业   1篇
无线电   1篇
冶金工业   1篇
自动化技术   3篇
  2010年   1篇
  2005年   1篇
  1999年   1篇
  1996年   3篇
排序方式: 共有6条查询结果,搜索用时 15 毫秒
1
1.
This paper presents a motion estimation and compensation large scale integration (LSI) for the MPEG2 standard. An embedded RISC processor and special hardware modules enable the LSI to achieve a sufficient ability to perform real-time operation and provide the availability to realize many kinds of block matching algorithms. Using a three-step hierarchical telescopic search algorithm, a single chip accomplishes real-time motion estimation with search ranges of ±32.5×±32.5 pixels for motion vectors. The chip was fabricated using 0.5-μm CMOS technology and has an area of 16.5×16.5 mm2 and 2.0 M transistors  相似文献   
2.
Cellulose β-ketoesters with branched alkenyl chains were prepared using cis-9-octadecenyl ketene dimer (OKD) and LiCl/1,3-dimethyl-2-imidazolidinone (DMI) as the esterifying reagent and cellulose solvent, respectively. Relationships between degree of substitution (DS) of the cellulose/OKD β-ketoesters and reaction conditions were studied in detail. The results showed that DS values of the products were controllable up to 2.1 by selecting the reaction conditions. Solution- and solid-state 13C-NMR analyses revealed that cellulose backbones of the cellulose/OKD β-ketoesters with DS 2.1 behave like solid in chloroform owing to strong restriction on movement of cellulose chains by the long and branched alkenyl substituents introduced. Size-exclusion chromatographic analysis showed that little depolymerization occurred on cellulose during β-ketoesterification at room temperature, and that molecules of the cellulose/OKD β-ketoesters with DS 2.1 had semi rigid-rod conformation in tetrahydrofuran. Thus, cellulose β-ketoesters with densely substituents like polymer brushes or comb-shaped polymers were prepared in this study.  相似文献   
3.
Disaster management systems are complex applications due to their distributed and decentralized nature. Various components execute in parallel with high need of coordination with each other. In such applications, interaction and communication issues are difficult to model and implement. In this paper, we have proposed agent-based Earthquake Management System (EMS) which is modeled and analyzed using formal approach. Traditionally, such systems undergo through various transformations starting from requirement models and specification to analysis, design and implementation. A variety of formal approaches are available to specify systems for analyzing their structure and behavior; however, there are certain limitations in using these techniques due to their expressiveness and behavior requirements. We have adopted combination of Pi-calculus and Pi-ADL formal languages to model EMS from analysis to design. The formal approach helps to enhance reliability and flexibility of the system by reducing the redundant information. It reduces chances of errors by explicitly mentioning working flow of information. Additionally, a prototype application is presented as proof of concept in EMS context. We have also evaluated our formal specification by using ArchWare and ABC tools; also, comparison of prototype application with major existing techniques is highlighted.  相似文献   
4.
Thanks to increased market acceptance of applications such as digital versatile disks (DVDs), HDTV, and digital satellite broadcasting, the MPEG-2 (Moving Picture Experts Group-2) standard is becoming widely used. The MPEG-2 video standard, established in 1934, provides for a high-quality video compression format that, through high bit rates and frame rates, yields high-resolution video images. Emerging multimedia applications, such as digital versatile disk and high-definition television, demand higher quality video than ever before. In response, our MPEG-2 video encoder chip supports multiple profiles and levels  相似文献   
5.
The clinical significance of the detection of Pneumocystis carinii DNA was evaluated, as well as the detection of circulating P. carinii antigen from serum using previously collected samples. Fourteen serum samples from 13 patients were diagnosed positively for P. carinii DNA by polymerase chain reaction (PCR). Ten of 14 episodes (71.4%) of pulmonary complications were compatible with P. carinii pneumonia. Two patients were definitely diagnosed as having had P. carinii pneumonia at autopsy. All patients positive for circulating antigens were also positive for P. carinii DNA, suggesting that the detection of P. carinii DNA by PCR is more sensitive compared to the detection of circulating antigens by the Ouchterlony method. It is concluded that the detection of P. carinii DNA in serum by PCR provides useful information for identifying P. carinii pneumonia.  相似文献   
6.
Our two-chip, real time, MPEG-2, simple-profile-at-main-level encoder supports NTSC 4:2:0 video signals with only three external memories. We have developed a compact encoder chip set. The key features of this chip set are a low encoding delay based on a simple profile at main level; wide-range motion estimation, which it performs using a hierarchical search; a flexible, macroblock level pipeline architecture based on RISC CPUs; and three small peripherals with no glue logic: a VRAM, synchronous DRAM, and FIFO DRAM  相似文献   
1
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