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131.
循环流化床半干法烟气脱硫(CFB-FGD)技术是目前烟气脱硫综合效益最优越的一种半干法烟气脱硫技术。文章主要设计并实现了CFB-FGD半干法烟气脱硫网络控制系统。该系统结合了快速以太网、工业以太网以及现场总线,构成三层控制网络;采用了合理的冗余结构,提高了系统的可靠性。实际的运行表明,该系统实现设计合理稳定,实现了半干法烟气脱硫的自动化控制,提高了脱硫效率。  相似文献   
132.
单机多媒体本地影像视频的应用在很久以前就已经得到重视,目前应用越来越广泛,虽然现在网络多媒体很流行,但是单机多媒体的地位是无法取代的。本论文以会声会影11制作科技馆十周年纪录短片为例,对单机多媒体本地影像视频的制作过程和其中注意事项进行探讨.  相似文献   
133.
本文设计了一种新的基于MPEG-2 TS流语法语义的数字视颇信号可变延时器。  相似文献   
134.
网络安全是目前国内外非常注重的网络问题,《网络安全技术》课程也是网络工程专业学生所学习的一门很重要的专业课。结合本校该课程的教学特点和学生的需求,对该课程的教学资料库进行建设,增加学生知识面,从而最大程度的提高教与学的效率。  相似文献   
135.
Customs and quarantine departments are applying information systems to automate their inspection processes and improve their inspection efficiency and accuracy. The product codes from the Harmonized System (HS codes) are the essential elements of the system's integration, automation and intelligence. The identified HS codes are well-accepted and precise product references used by customs authorities, to match applicable policies to the products being inspected and taxed. Domain ontology for importing and exporting industry can be used to acquire HS codes for given products, and is a prerequisite for an integrated and intelligent automated inspection system. The authors have proposed and implemented an importing and exporting domain ontology. The ontology is composed of an integrated and comprehensive knowledge base derived from static dictionaries and the HS specification, and dynamic processing data. Based on this ontology, a reasoning engine is developed to generate HS codes intelligently for the given product names. Information systems can use the engine to get HS codes for submitted products and find applicable policies automatically. The ontology and the engine have been implemented in a Java-based platform and published as a HS Web service. In this paper, knowledge structure, reasoning mechanism and implementation details for the domain ontology and reasoning engine are presented. A test bed in the application environment has been conducted and experimental results have been obtained. The ontology and the service have the potential to be widely used by authorities and international traders of importing and exporting industry around the world.  相似文献   
136.
An improved algorithm is developed based on support vector regression (SVR) to estimate horizonal water vapor transport integrated through the depth of the atmosphere (Θ) over the global ocean from observations of surface wind-stress vector by QuikSCAT, cloud drift wind vector derived from the Multi-angle Imaging SpectroRadiometer (MISR) and geostationary satellites, and precipitable water from the Special Sensor Microwave/Imager (SSM/I). The statistical relation is established between the input parameters (the surface wind stress, the 850 mb wind, the precipitable water, time and location) and the target data (Θ calculated from rawinsondes and reanalysis of numerical weather prediction model). The results are validated with independent daily rawinsonde observations, monthly mean reanalysis data, and through regional water balance. This study clearly demonstrates the improvement of Θ derived from satellite data using SVR over previous data sets based on linear regression and neural network. The SVR methodology reduces both mean bias and standard deviation compared with rawinsonde observations. It agrees better with observations from synoptic to seasonal time scales, and compare more favorably with the reanalysis data on seasonal variations. Only the SVR result can achieve the water balance over South America. The rationale of the advantage by SVR method and the impact of adding the upper level wind will also be discussed.  相似文献   
137.
The Individual Haplotyping MFR problem is a computational problem that, given a set of DNA sequence fragment data of an individual, induces the corresponding haplotypes by dropping the minimum number of fragments. Bafna, Istrail, Lancia, and Rizzi proposed an algorithm of time O(22k m 2 n+23k m 3) for the problem, where m is the number of fragments, n is the number of SNP sites, and k is the maximum number of holes in a fragment. When there are mate-pairs in the input data, the parameter k can be as large as 100, which would make the Bafna-Istrail-Lancia-Rizzi algorithm impracticable. The current paper introduces a new algorithm PM-MFR of running time , where k 1 is the maximum number of SNP sites that a fragment covers (k 1 is smaller than n), and k 2 is the maximum number of fragments that cover a SNP site (k 2 is usually about 10). Since the time complexity of the algorithm PM-MFR is not directly related to the parameter k, the algorithm solves the Individual Haplotyping MFR problem with mate-pairs more efficiently and is more practical in real biological applications. This research was supported in part by the National Natural Science Foundation of China under Grant Nos. 60433020 and 60773111, the Program for New Century Excellent Talents in University No. NCET-05-0683, the Program for Changjiang Scholars and Innovative Research Team in University No. IRT0661, and the Scientific Research Fund of Hunan Provincial Education Department under Grant No. 06C526.  相似文献   
138.
With an increasing acceptance of Wireless Sensor Networks (WSNs), the health of individual sensor is becoming critical in identifying important events in the region of interest. One of the key challenges in detecting event in a WSN is how to detect it accurately transmitting minimum information providing sufficient details about the event. At the same time, it is also important to devise a strategy to handle multiple events occurring simultaneously. In this paper, we propose a Polynomial-based scheme that addresses these problems of Event Region Detection (PERD) by having a aggregation tree of sensor nodes. We employ a data aggregation scheme, TREG (proposed in our earlier work) to perform function approximation of the event using a multivariate polynomial regression. Only coefficients of the polynomial (PP) are passed instead of aggregated data. PERD includes two components: event recognition and event report with boundary detection. This can be performed for multiple simultaneously occurring events. We also identify faulty sensor(s) using the aggregation tree. Performing further mathematical operations on the calculated PP can identify the maximum (max) and minimum (min) values of the sensed attribute and their locations. Therefore, if any sensor reports a data value outside the [min, max] range, it can be identified as a faulty sensor. Since PERD is implemented over a polynomial tree on a WSN in a distributed manner, it is easily scalable and computation overhead is marginal. Results reveal that event(s) can be detected by PERD with error in detection remaining almost constant achieving a percentage error within a threshold of 10%10% with increase in communication range. Results also show that a faulty sensor can be detected with an average accuracy of 94%94% and it increases with increase in node density.  相似文献   
139.
模糊C-均值(FCM)聚类算法的实现   总被引:11,自引:0,他引:11  
传统的FCM算法能够将靠近边界的具有固有形状的两个簇合并成为一个大的簇.然而,对于一些稍微复杂的数据,如果没有其它的像去除小簇之类的机制的话,FCM算法很难将非常接近的类聚类到一起.给出的聚类算法是在传统FCM算法的循环之后添加了去除掉空簇的步骤,解决了上述很难将非常接近的类聚到一个簇中的问题.另外,为便于选出最优结果,在递归之后又添加了计算聚类有效性的步骤.最后用Java实现了该算法并在数据集上进行了实验,证实了改进方法的有效性.  相似文献   
140.
码间串扰和信道噪声是影响基带传输系统性能的两个主要因素。因此,如何消除它们的影响,使系统的误码率达到规定的要求是数字基带系统中必须研究的两个问题。奈奎斯特第一准则为消除码间串扰奠定了理论基础。本文将以此为依据,通过使用Systemview和MATLAB软件实现对基带传输系统的仿真,并根据所得图形从消除码间串扰的角度来定性地分析无码间串扰系统函数的传输特性。实验中所得结果将对我们的理解和实践均有一定的指导作用。  相似文献   
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