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模规MG-1的光束质量检测实验 被引量:3
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作者 杨成龙 程晓峰 +4 位作者 岳正普 丁有义 邱服民 杨英 吕百达 《强激光与粒子束》 EI CAS CSCD 1994年第4期485-490,共6页
在高斯光束传输方程的基础上,介绍了模规MG-1的组成和工作原理,给出了单模稳频He-Ne激光和Ar ̄+激光光束质量的实验测试结果。
关键词 模规 光束质量 MG-1 检测
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建德:通过创建省环境保护模范城市规划
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作者 周义盼 《杭州》 2012年第6期77-77,共1页
近日,浙江省专家组一行听取了建德市创模办关于《建德市创建浙江省环境保护模范城市规划》主要内容及编制情况的汇报,并进行了论证。经过专家组的认真讨论,一致认为创模规划方案定位明确、规划内容合理、重点突出,对创模目标具有引领作... 近日,浙江省专家组一行听取了建德市创模办关于《建德市创建浙江省环境保护模范城市规划》主要内容及编制情况的汇报,并进行了论证。经过专家组的认真讨论,一致认为创模规划方案定位明确、规划内容合理、重点突出,对创模目标具有引领作用。建德市创建省环境保护模范城市的规划创建阶段为2011~2013年。 展开更多
关键词 环境保护范城市 建德市 划内容 浙江省 专家组 重点突出 方案定位 主要内容 经济强市 模规
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一种用于5G的大规模MIMO天线阵设计 被引量:5
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作者 毛建军 于大群 焦永昌 《现代雷达》 CSCD 北大核心 2016年第2期66-69,共4页
设计了一种用于第五代移动通信系统的大规模MIMO天线阵。该天线阵采用8×8矩形排布,天线单元采用缝隙耦合馈电的贴片形式,通过蚀刻在上层地板上的两个正交H型缝隙对辐射贴片分别耦合馈电来实现±45°双线极化特性。所设计... 设计了一种用于第五代移动通信系统的大规模MIMO天线阵。该天线阵采用8×8矩形排布,天线单元采用缝隙耦合馈电的贴片形式,通过蚀刻在上层地板上的两个正交H型缝隙对辐射贴片分别耦合馈电来实现±45°双线极化特性。所设计的天线阵工作在3.4 GHz^3.6 GHz,具有剖面低、结构紧凑、便于与射频前端集成化设计的特点,能够很好地满足下一代移动通信系统对天线阵的设计要求。 展开更多
关键词 耦合缝隙
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大规模多输入多输出系统中的导频污染降低策略
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作者 张书畅 张仁迟 《科学技术与工程》 北大核心 2017年第18期74-77,共4页
在大规模多输入多输出(massive multiple-input multiple-output,Massive MIMO)系统中,小区边缘用户遭受严重的导频污染,由此提出一种新的导频污染降低策略。根据大尺度衰落系数将小区内用户划分为中心用户和边缘用户,中心用户复用相同... 在大规模多输入多输出(massive multiple-input multiple-output,Massive MIMO)系统中,小区边缘用户遭受严重的导频污染,由此提出一种新的导频污染降低策略。根据大尺度衰落系数将小区内用户划分为中心用户和边缘用户,中心用户复用相同的一组导频序列,边缘用户使用相互正交的导频序列组。理论分析和仿真结果均表明,该策略能够有效地提升每个小区多用户的上行可达和速率,降低系统中的导频污染。 展开更多
关键词 MIMO 导频污染 导频分配
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Effects of Group Size on Vigilance Behavior of Wintering Common Cranes Grus grus 被引量:12
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作者 杨洋 陈文华 +3 位作者 江望高 杨士剑 彭贵鸿 黄庭发 《Zoological Research》 CAS CSCD 北大核心 2006年第4期357-362,共6页
From January to March 2005, the effects of group size on the vigilance behavior of wintering Common Cranes Grus grus were studied at Lashihai Lake, Yunnan Province, China. We used scan sampling to record the group siz... From January to March 2005, the effects of group size on the vigilance behavior of wintering Common Cranes Grus grus were studied at Lashihai Lake, Yunnan Province, China. We used scan sampling to record the group sizes and the number of vigilant individuals in each group, and focal sampling to record the frequency and duration of individual vigilance behavior. Both the vigilance efforts of groups and individuals significantly decreased as group size increased, but when the group size exceeded 30 individuals, the decrease of group vigilance became not significant (P 〉 0. 05), and the vigilance duration of adult cranes increased (P 〈 0.01 ). The vigilance frequency of adults increased (P 〈 0.05) when the size exceeded 50 individuals. Presumably, the maximal group size allowing the lowest vigilance for juvenile cranes was larger than that for adults, and the flocks composed of 20 to 30 individuals represented the optimal group size of wintering Common Cranes by considering only the vigilance behavior. Further research should focus on the synthesized effects of various factors. 展开更多
关键词 Grus grus Group size Vigilance effort Frequency DURATION
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Creep experiment and rheological model of deep saturated rock 被引量:11
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作者 刘浪 王革民 +1 位作者 陈建宏 杨珊 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第2期478-483,共6页
By the methods of uniaxial single-stage loading and graded incremental cyclic loading, the creep experiments were performed on the deep saturated rock from Dongguashan Mine, and the creep curves of saturated rock unde... By the methods of uniaxial single-stage loading and graded incremental cyclic loading, the creep experiments were performed on the deep saturated rock from Dongguashan Mine, and the creep curves of saturated rock under different loading stresses were obtained. By comparing with the creep rule of dry rock in the same location, the creep rule of deep saturated rock was analyzed. Based on the united rheological mechanical model, the rheological model of deep saturated rock was recognized, and the parameters of the model were determined. The results show that the creep curves are very smooth under low stress, but the phenomena of wave and catastrophe turn up under high stress, and the bearing capacity of rock is weakening over time. The rheological properties of saturated and dry rocks are very different under tlie condition of deep high stress, especially when unloading, degradation and damage of rock quality is more serious, and the effect of water cannot be neglected. The H--HIN--NJS model (Schofield-Scott-Blair model) was selected to represent the rheology rule of deep saturated rock, and the fitting curves of model agree well with the experiment data, so the selected model is reasonable. 展开更多
关键词 deep saturated rock CREEP united rheological model rheology rule
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Text categorization based on fuzzy classification rules tree 被引量:2
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作者 郭玉琴 袁方 刘海博 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期339-342,共4页
To deal with the problem that arises when the conventional fuzzy class-association method applies repetitive scans of the classifier to classify new texts,which has low efficiency, a new approach based on the FCR-tree... To deal with the problem that arises when the conventional fuzzy class-association method applies repetitive scans of the classifier to classify new texts,which has low efficiency, a new approach based on the FCR-tree(fuzzy classification rules tree)for text categorization is proposed.The compactness of the FCR-tree saves significant space in storing a large set of rules when there are many repeated words in the rules.In comparison with classification rules,the fuzzy classification rules contain not only words,but also the fuzzy sets corresponding to the frequencies of words appearing in texts.Therefore,the construction of an FCR-tree and its structure are different from a CR-tree.To debase the difficulty of FCR-tree construction and rules retrieval,more k-FCR-trees are built.When classifying a new text,it is not necessary to search the paths of the sub-trees led by those words not appearing in this text,thus reducing the number of traveling rules.Experimental results show that the proposed approach obviously outperforms the conventional method in efficiency. 展开更多
关键词 text categorization fuzzy classification association rule classification rules tree fuzzy classification rules tree
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METHOD FOR BRIDGE BEARING CAPACITY ASSESSMENT BASED ON ANALYTIC HIERARCHY PROCESS 被引量:2
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作者 张丽芳 艾军 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第3期235-241,共7页
By analyzing the existing methods for the bridge bearing capacity assessment, an analytic hierarchy pro cess estimation model with a variable weight and fuzzy description is proposed based on the nondestructive infor ... By analyzing the existing methods for the bridge bearing capacity assessment, an analytic hierarchy pro cess estimation model with a variable weight and fuzzy description is proposed based on the nondestructive infor mation. Considering the actual strength, the bearing capacity is first calculated from its design state, and then modified based on the detection information. The modification includes the section reduction and the structure deterioration. The section reduction involves the concrete section and the steel cross-section reduction. The structure deterioration is decided by six factors, i.e. , the concrete surface damage, the actual concrete strength, the steel corrosion electric potential, the chloride ion content, the carbonization depth, and the protective layer depth. The initial weight of each factor is calculated by the expert judgment matrix using an analytic hierarchy process. The consistency approximation and the error transfer theory are used. Then, the variable weight is in- troduced to expand the influences of factors in the worse state. Finally, an actual bridge is taken as an example to verify the proposed method. Results show that the estimated capacity agrees well with that of the load test, thus the method is objective and credible 展开更多
关键词 BRIDGES bearing capacity fuzzy rules variable weight analytic hierarchy process
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Fuzzy programming approach solution for multi-objective solid transportation problem 被引量:3
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作者 韩世莲 李旭宏 《Journal of Southeast University(English Edition)》 EI CAS 2004年第1期102-107,共6页
Based on recent research developments in multi-objective solid transportation problem (MOSTP), this paper presents a fuzzy programming approach to determine the optimal compromise solution of MOSTP. The characteristic... Based on recent research developments in multi-objective solid transportation problem (MOSTP), this paper presents a fuzzy programming approach to determine the optimal compromise solution of MOSTP. The characteristic feature of the proposed approach is that various objectives are synthetically considered with marginal evaluation for individual objectives and global evaluation for all objectives. The decision-maker's preference is taken into account by his/her assigning weights to the objectives. With global evaluation for all objectives, a compromise programming model is formulated. As a generic aggregation operator is adopted, several solution methods proposed earlier become special cases of this approach, and the solution process also becomes more flexible and realistic. An illustrative numerical example is provided to demonstrate the approach. 展开更多
关键词 Fuzzy sets Global optimization
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Novel process for large scale synthesis of N-(4-hydroxyphenyl) retinamide 被引量:1
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作者 吴晓晴 余佳 吉民 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期247-249,共3页
A method to synthesize anticancer drug N-( 4- hydroxyphenyl) retinamide (4-HPR)on a large scale is described. It consists of the preferred steps of reacting all-trans retinoic acid with thionyl chloride to form re... A method to synthesize anticancer drug N-( 4- hydroxyphenyl) retinamide (4-HPR)on a large scale is described. It consists of the preferred steps of reacting all-trans retinoic acid with thionyl chloride to form retinoyl chloride and then reacting with triethylamine to generate retinoyl ammonium salt which in turn is reacted with p-aminophenol to eventually produce 4-HPR. This process can overcome many scale-up challenges that exist in the methods reported in the literature and provide an easy, mild and high yield route for large scale synthesis of 4-HPR. Moreover, the effects of the molar ratios of the reagents on the yield are examined. The best molar ratios are a 2.0 molar equivalence of thionyl chloride and a 3.0 molar equivalence of paminophenol to retinoic acid, and the total yield is 80. 7%. 展开更多
关键词 4-HPR large scale SYNTHESIS ANTICANCER
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Influential Factors on Economic Benefit of Rice Farmers 被引量:2
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作者 齐振宏 綦校海 +1 位作者 王磊 陈庆根 《Agricultural Science & Technology》 CAS 2012年第2期460-467,共8页
[Objective] This study was to provide references for the improvement of agricultural economic benefit by analyzing the main factors on influencing the economic benefit of rice farmer. [Method] Field survey was carried... [Objective] This study was to provide references for the improvement of agricultural economic benefit by analyzing the main factors on influencing the economic benefit of rice farmer. [Method] Field survey was carried out on 300 rice farmers in Suizhou, Wuxue and Xiaogan of Hubei Province. Through the descriptive statistics to the production input and output data of the sample farmers, the econometric model was established to conduct empirical test on the economic benefit of rice farmer and the influential factors. The optimal production scale for rice farmer was also estimated, and through the theoretical and empirical analysis of the optimal production scale, countermeasures were put forward with the aim to promote economic benefit of rice farmer. [Result] The application of fertilizer affected the economic benefit most, followed by the planting area; food policy, farming population and average economic income per capita had significant effects on the economic benefit of rice production; economic benefit was beneficial for cost control. [Conclusion] This study had great practical and instructive significance for stabilizing national food production, ensuring regional and national food safety. 展开更多
关键词 Economic benefit Rice farmers Influential factor Optimal planting scale
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Research on the Effect of Microbial Fermentation Feeds on Slaughter Performance and Meat Quality in Pig with Large-scale Feeding 被引量:9
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作者 林标声 罗建 +1 位作者 李益明 杨小燕 《Agricultural Science & Technology》 CAS 2016年第10期2329-2331,2382,共4页
In this paper, Duroc-lanndrae-Yorkshire crossbred piggy of born at 75 days of age, bouncing with health and similar body weight were randomly divided into experimental group (136 pigs) and control group (136 pigs)... In this paper, Duroc-lanndrae-Yorkshire crossbred piggy of born at 75 days of age, bouncing with health and similar body weight were randomly divided into experimental group (136 pigs) and control group (136 pigs). Pigs in control group were fed with conventional diets, and 4% microbial fermentation feeds were added to the basal diet of experimental group to research on the effect of performance and meat quality of pig breeding. The results indicated that after feeding 106 d, compared to control group, the slaughter performance, meat quality and content of fatty acid and amino acid of experimental group were all better, its slaughter rate increased 1.53%, the carcass weight increased 2.75% and the backfat thickness decreased 0.02 cm. In addition, the pork meat in test group hadn't antibiotic and heavy metal residues, while it had higher color score, lower pH45min and pH24h value, better tenderness and rate of cooked meat and higher content of fatty acids, polyunsaturated fatty acids and amino acids. Microbial fermentation feed using in test group can significantly improved the flavor and aroma of pork, and eating this pork conducive more to human health. Thus, the application of microbial fermenta- tion feed can provide a more safe, healthy and nutritious flavor pork for human beings. 展开更多
关键词 Microbial fermentation feeds Large-scale feeding Slaughter performance Meat quality
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Large_scale Isolation and Purification of R_phycoerythrin from Red Alga Palmaria palmata Using the Expanded Bed Adsorption Method 被引量:2
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作者 王广策 孙海宝 +1 位作者 范晓 曾呈奎 《Acta Botanica Sinica》 CSCD 2002年第5期541-546,共6页
R-phycoerythrin, a light-harvesting protein in some marine algae, and can be widely used in medicine, was isolated and purified from a red alga, Palmaria palmata (Lannaeus) Kuntze, using the streamline column (expande... R-phycoerythrin, a light-harvesting protein in some marine algae, and can be widely used in medicine, was isolated and purified from a red alga, Palmaria palmata (Lannaeus) Kuntze, using the streamline column (expanded bed adsorption) combined with ion-exchange chromatography. Because the crude extract was applied to the column upwardly, the column would not be blocked by polysaccharides usually very abundant in the extract of marine alga, this kind of blockage could hardly lie overcome in ordinary chromatographic column. After applying the crude extract containing 0.5 mol/L (NH4)(2)SO4, (NH4)(2)SO4 solution of different concentrations (0.2 mol/L, 0.1 mol/L and 0.05 mol/L) was used to elute the column downwardly and the eluates were collected and desalted. The desalted eluates were then applied onto all ion-exchange chromatographic column loaded with Q-sepharose for further purification of the R-phycoerythrin. Through these two steps, the purity (OD565/OD280) of the R-phycoerythrin from P. palmata was up to 3.5, more than 3.2, the commonly accepted criterion for purity, and the yield of the purified R-phycoerythrin could reach 0.122 mg/g of frozen P. palmata, much higher than that of phycobiliproteins purified with the previous methods. The result indicated that the cost of R-phycoerythrin will drop down with the method reported in this article. 展开更多
关键词 Palmaria palmata ( Lannaeus) Kuntze R-PHYCOERYTHRIN streamline column ion-exchange chromatography
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Configuration knowledge modeling of customizable products based on semantic web technologies 被引量:1
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作者 叶艳 杨东 江志斌 《Journal of Southeast University(English Edition)》 EI CAS 2006年第3期418-422,共5页
In order to solve the problem of modeling product configuration knowledge at the semantic level to successfully implement the mass customization strategy, an approach of ontology-based configuration knowledge modeling... In order to solve the problem of modeling product configuration knowledge at the semantic level to successfully implement the mass customization strategy, an approach of ontology-based configuration knowledge modeling, combining semantic web technologies, was proposed. A general configuration ontology was developed to provide a common concept structure for modeling configuration knowledge and rules of specific product domains. The OWL web ontology language and semantic web rule language (SWRL) were used to formally represent the configuration ontology, domain configuration knowledge and rules to enhance the consistency, maintainability and reusability of all the configuration knowledge. The configuration knowledge modeling of a customizable personal computer family shows that the approach can provide explicit, computerunderstandable knowledge semantics for specific product configuration domains and can efficiently support automatic configuration tasks of complex products. 展开更多
关键词 knowledge modeling semantic web technology product configuration mass customization
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Measuring technical efficiency of Chinese nonferrous metals enterprises on a background of industry consolidation 被引量:5
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作者 危平 唐慧泉 +1 位作者 陈瑶 陈晓红 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第9期2797-2806,共10页
Since 2009, Chinese nonferrous metals industry has been carried out industry consolidation with strong support by the central government. This work examined technical efficiency of Chinese nonferrous metals firms and ... Since 2009, Chinese nonferrous metals industry has been carried out industry consolidation with strong support by the central government. This work examined technical efficiency of Chinese nonferrous metals firms and its change during the period of 2007 and 2011. Based on financial data from nonferrous metals listed companies, technical efficiency of nonferrous metal minerals mining firms and nonferrous metal smelting, pressing and processing firms was estimated respectively using the data envelopment analysis (DEA) method. It was found that, in both sectors, number of pure technical and scale inefficient firms dominated over efficient ones. Overall, their technical and scale efficiency tended to be very low after 2009. In particular, efficiency scores of nonferrous metal smelting, pressing and processing firms fluctuated greatly during the research period. And a limited number of large leading firms were able to maintain 100% efficiency score in the industry, while efficiency of most of other leading firms has declined since 2009. 展开更多
关键词 industry consolidation nonferrous metals finns data envelopment analysis (DEA) technical efficiency scale efficiency CONGLOMERATE
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Construction of Risk Assessment Application Model of Epidemic Disease in Large-scale Pig Farms 被引量:1
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作者 谭业平 刘强 +3 位作者 胡肄农 郁达威 何孔旺 陆昌华 《Agricultural Science & Technology》 CAS 2016年第9期2124-2126,共3页
The application model of epidemic disease assessment technology for Web-based large-scale pig farm was expounded from the identification of epidemic disease risk factors, construction of risk assessment model and deve... The application model of epidemic disease assessment technology for Web-based large-scale pig farm was expounded from the identification of epidemic disease risk factors, construction of risk assessment model and development of risk assessment system. The assessed pig farm uploaded the epidemic disease risk data information through on-line answering evaluating questionnaire to get the immediate evaluation report. The model could enhance the risk communication between pig farm veterinarian, manager and veterinary experts to help farm system understand and find disease risk factors, assess and report the potential high risk items of the pig farm in the three systems of engineering epidemic disease prevention technology, biological safety and immune monitoring, and promote the improvement and perfection of epidemic disease prevention and control measures. 展开更多
关键词 Large-scale pig farm Risk assessment of epidemic disease Model construction
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Fame:A Fast Detailed Placement Algorithm for Standard\| Cell Layout Based on Mixed Mincut and Enumeration 被引量:1
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作者 姚波 侯文婷 +1 位作者 洪先龙 蔡懿慈 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2000年第8期744-753,共10页
Rapid progress in manufacturing greatly challenges to the VLSI physical design in both speed and performance. A fast detailed placement algorithm, FAME is presented in this paper, according to these demands. It inhe... Rapid progress in manufacturing greatly challenges to the VLSI physical design in both speed and performance. A fast detailed placement algorithm, FAME is presented in this paper, according to these demands. It inherits the optimal positions of cells given by a global placer and exact position to each cell by local optimization. FM Mincut heuristic and local enumeration are used to optimize the total wirelength in y and x directions respectively, and a two way mixed optimizing flow is adopted to combine the two methods for a better performance. Furthermore, a better enumeration strategy is introduced to speed up the algorithm. An extension dealing with blockages in placement has also been discussed. Experimental results show that FAME runs 4 times faster than RITUAL and achieves a 5% short in total wirelength on average. 展开更多
关键词 detailed placement layout VLSI mincut optimization
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Diagnosis of Mixed Infection of CSFV, PRV and E.coli in a Modern Pig Farm of Guizhou Province 被引量:2
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作者 龙冬梅 韦冠东 +4 位作者 汤德元 王洪光 曾智勇 李达 李谦 《Agricultural Science & Technology》 CAS 2016年第8期1906-1908,共3页
In order to understand the incidence reasons in a scaled pig farm of Guizhou Province, the infected pigs were diagnosed with epidemiological investigation, clinical observation, pathological diagnosis, enzyme-linked i... In order to understand the incidence reasons in a scaled pig farm of Guizhou Province, the infected pigs were diagnosed with epidemiological investigation, clinical observation, pathological diagnosis, enzyme-linked immunosorbent assay (ELISA), PCR/RT-PCR and bacterial isolation and identification. The results showed that the pigs were infected mixedly with classical swine fever virus (CSFV), pseudorabies virus (PRV) and E. coli. Therefore, some measures should be adopted to control the incidence of CSF, PR and colibacillosis in the pig farm. 展开更多
关键词 Guizhou Province Scaled pig farm Classical swine fever (CSF) Pseudorabies (PR) E. coil Mixed infection
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Challenges to Data-Path Physical Design Inside SOC 被引量:2
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作者 经彤 洪先龙 +5 位作者 蔡懿慈 许静宇 杨长旗 张轶谦 周强 吴为民 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第8期785-793,共9页
Previously,a single data-path stack was adequate for data-path chips,and the complexity and size of the data-path was comparatively small.As current data-path chips,such as system-on-a-chip (SOC),become more complex,m... Previously,a single data-path stack was adequate for data-path chips,and the complexity and size of the data-path was comparatively small.As current data-path chips,such as system-on-a-chip (SOC),become more complex,multiple data-path stacks are required to implement the entire data-path.As more data-path stacks are integrated into SOC,data-path is becoming a critical part of the whole giga-scale integrated circuits (GSI) design.The traditional physical design methodology can not satisfy the data-path performance requirements,because it can not accommodate the data-path bit-sliced structure and the strict performance (such as timing,coupling,and crosstalk) constraints.Challenges in the data-path physical design are addressed.The fundamental problems and key technologies in data-path physical design are analysed.The corresponding researches and solutions in this research field are also discussed. 展开更多
关键词 physical design data-path bit-sliced structure SYSTEM-ON-A-CHIP giga-scale integrated circuits very-deep-submicron
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Empirical Analysis on Rural Financial Development and Farmers' Income Increase in China 被引量:2
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作者 邹小芳 黎东升 《Agricultural Science & Technology》 CAS 2015年第4期774-776,781,共4页
The growth of farmer's incomes is cIoseIy reIated to rural finance. The research analyzed the dynamic reIationship of rural financial deveIopment, efficiency and farmer's incomes based on VAR modeI, and the resuIts ... The growth of farmer's incomes is cIoseIy reIated to rural finance. The research analyzed the dynamic reIationship of rural financial deveIopment, efficiency and farmer's incomes based on VAR modeI, and the resuIts indicated that the ex-pansion of rural finance wouId stimuIate farmer's incomes in a Iong term, and the growth of rural financial efficiency significantIy improves farmer's incomes in a short term, instead of a Iong term. Hence, it is necessary to introduce more credit funds and social funds to rural areas, deepen rural financial system reform and acceIerate use rate of Ioan capital and enhance guidance for farmers and township enterprises in use of Ioan capitals. 展开更多
关键词 Financlal scale in rural areas Rural financlal efficlency Farmer&#39 s in-comes ImpuIse response functlon
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