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Soft Computing of Biochemical Oxygen Demand Using an Improved T–S Fuzzy Neural Network 被引量:4
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作者 乔俊飞 李微 韩红桂 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第Z1期1254-1259,共6页
It is difficult to measure the online values of biochemical oxygen demand(BOD) due to the characteristics of nonlinear dynamics, large lag and uncertainty in wastewater treatment process. In this paper, based on the k... It is difficult to measure the online values of biochemical oxygen demand(BOD) due to the characteristics of nonlinear dynamics, large lag and uncertainty in wastewater treatment process. In this paper, based on the knowledge representation ability and learning capability, an improved T–S fuzzy neural network(TSFNN) is introduced to predict BOD values by the soft computing method. In this improved TSFNN, a K-means clustering is used to initialize the structure of TSFNN, including the number of fuzzy rules and parameters of membership function. For training TSFNN, a gradient descent method with the momentum item is used to adjust antecedent parameters and consequent parameters. This improved TSFNN is applied to predict the BOD values in effluent of the wastewater treatment process. The simulation results show that the TSFNN with K-means clustering algorithm can measure the BOD values accurately. The algorithm presents better approximation performance than some other methods. 展开更多
关键词 BIOCHEMICAL oxygen demand WAsTEWATER treatment T–s fuzzy NEURAL network K-MEANs clustering
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Cotton's Water Demand and Water-Saving Benefits under Drip Irrigation with Plastic Film Mulch 被引量:2
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作者 Yingyu YAN Juyan LI 《Asian Agricultural Research》 2016年第4期32-36,41,共6页
The primary purpose of this research was to give suitable irrigation program according to the growth period and water requirement.A cotton field experiment with mulched drip irrigation was conducted at the National Fi... The primary purpose of this research was to give suitable irrigation program according to the growth period and water requirement.A cotton field experiment with mulched drip irrigation was conducted at the National Field Observation and Research Station for Oasis Farmland Ecosystem in Aksu of Xinjiang in 2008.Water balance method was adopted to study the water requirement and water consumption law of cotton under mulched drip irrigation in Tarim Irrigated Area.Statistical analysis of experimental data of irrigation indicates that the relationship between yield of cotton and irrigation presents a quadratic parabola.We fit the model of cotton water production on the basis of field experimental data of cotton.And the analysis on water saving benefit of cotton under mulched drip irrigation was done.Results indicate that water requirements for the irrigated cotton are 543 mm in Tarim Irrigated Area.The water requirements of seedling stage is 252 mm,budding stage is 186 mm,bolling stage is 316 mm and wadding stage is 139 mm.the irrigation amount determines the spatial distribution of soil moisture and water consumption during cotton life cycle.However,water consumption at different growth stages was inconsistent with irrigation.Quantitatively,the water consumed by cotton decreases upon the increase of irrigation amount.From the perspective of water saving,the maximal water use efficiency can reach 3 091 m3/ha.But the highest cotton yield needs 3464 m3/ha irrigation water.In summary,compared to the conventional drip irrigation,a number of benefits in water saving and yield increase were observed when using plastic mulch.At the same amount of irrigation,the cotton yield with plastic mulch was 30.2% higher than conventional approaches,and the efficiency of water utilization increased by30.2%.While at the same yield level,29.3% water was saved by using plastic mulch,and the efficiency increased by 41.5%. 展开更多
关键词 Cotton’s WATER demand Cotton’s WATER consumption WATER-sAVING BENEFITs DRIP irrigation with PLAsTIC film MULCH
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Booming Demand in China’s Second-hand Market——2018 Development Report for China Second-hand E-businesses
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作者 Lynn Yu 《China's Foreign Trade》 2019年第3期47-49,共3页
On June 3rd,JD.com announced that Paipai,its second-hand commodity trade platform,was strategically merged with Aihuishou(Love Recycling)which is one of the largest electronics recycling platforms in China.Recently,th... On June 3rd,JD.com announced that Paipai,its second-hand commodity trade platform,was strategically merged with Aihuishou(Love Recycling)which is one of the largest electronics recycling platforms in China.Recently,the Ecommerce Research Centre of 100ec.cn released the2018 Development Report for China Second-hand E-businesses(hereinafter referred to as the Report),which indicated that as of the end of 2017. 展开更多
关键词 China service Development Report for China second-hand E-businesses BOOMING demand in China’s second-hand MARKET
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China's Auto Market Demand Potential
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作者 Mao Xuan 《China's Foreign Trade》 1997年第3期31-32,共2页
In the 1980s, China’s auto market saw three dramatic fluctuations. Since the beginning of the 1990s, the market, as a whole, has become calm and stable without any major changes, though it has never evaded occasional... In the 1980s, China’s auto market saw three dramatic fluctuations. Since the beginning of the 1990s, the market, as a whole, has become calm and stable without any major changes, though it has never evaded occasional rises and fails. The pattern of demand on the market has been generally set and clear, and has begun to grow steadily. In view of the present situation, two major categories of vehicles—office-use and business or service use cars and trucks—have long been in demand on the market, almost dominat- 展开更多
关键词 AUTO China’s Auto Market demand Potential
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TRANSFORM THE MECHANISM OF RENMINBI’S EXCHANGE RATE SYSTEM IN CONFORMITY WITH THE DEMAND OF MARKET ECONOMY——The academic report delivered at the Annual Meeting of NNCIFS on October 1993
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作者 Qian Rongkun NANKAI UNIVERSITY.Cui Yonglu 《南开经济研究》 CSSCI 北大核心 1994年第S1期2-11,共10页
Exchange rate functions under systems of centrallyplanned economy and market economy are quite different,and the mechanism to determine such exchange rate is alsodifferent. To adopt a socialist market economic system ... Exchange rate functions under systems of centrallyplanned economy and market economy are quite different,and the mechanism to determine such exchange rate is alsodifferent. To adopt a socialist market economic system inChina, the exchange rate mechanism of Renminbi must bethoroughly transformed. To accomplish this goal, I believethere are three problems that must be solved: first, 展开更多
关键词 rate TRANsFORM THE MECHANIsM OF RENMINBI The academic report delivered at the Annual Meeting of NNCIFs on October 1993 s EXCHANGE RATE sYsTEM IN CONFORMITY WITH THE demand OF MARKET ECONOMY
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China's Growing Demand For PVC
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《China's Foreign Trade》 1999年第7期36-36,共1页
ChinawillneedmorepolyVinylchloride(PVC)in1999,ChinaLightindustryNewsreports.PVCisusedintheproductionofplasticsandplasticsheetingforagriculturaluse.IndusalanalystspredictariseinPVCdemandbecauseoftheincreaseduseoftheshe... ChinawillneedmorepolyVinylchloride(PVC)in1999,ChinaLightindustryNewsreports.PVCisusedintheproductionofplasticsandplasticsheetingforagriculturaluse.IndusalanalystspredictariseinPVCdemandbecauseoftheincreaseduseofthesheeting.TheexpansionofChina'slandco... 展开更多
关键词 China’s Growing demand For PVC
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Status and Perspective of Demand Resource Market in Korea's Electric Power Industry
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作者 Don Hur 《Journal of Energy and Power Engineering》 2012年第4期591-600,共10页
This paper calls attention to the demand resource market in Korea which opened in 2008 to reduce customers' consumption at critical times and, at the same time, secure the load that can be shut down. In Korea, the de... This paper calls attention to the demand resource market in Korea which opened in 2008 to reduce customers' consumption at critical times and, at the same time, secure the load that can be shut down. In Korea, the demand resource market is operated by either forward market or spot market. The discussion here is limited to the operations of the demand resource spot market. As the demand response program has matured in the smart grid environment, KPX (Korea Power Exchange) will shortly complete the development of the real-time demand resource trading system, taking into account an integrated dispatch system. 展开更多
关键词 demand response demand resource market Korea's electric power industry.
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Saurer's View The Chinese Demand Optimisim
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《China Textile》 2006年第1期86-88,共3页
Mr. H Fischer, the CEO of Saurer’s Speech on Chinese Textile Machinery Market and Investments in 2006 at the China Textile Round Table Forum, Beijing.
关键词 VIEW WILL saurer’s View The Chinese demand Optimisim
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China's economic growth pushed by domestic demand and relevant measures
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作者 Tao Runyuan 《中国远洋航务》 2002年第3期30-33,共4页
By contrast to a slowdown in the world economy, China kept up a rapid growth rate, a relatively high quality of growth and low inflation for the year 2001. This is mainly due to the result of proactive fiscal policies... By contrast to a slowdown in the world economy, China kept up a rapid growth rate, a relatively high quality of growth and low inflation for the year 2001. This is mainly due to the result of proactive fiscal policies that the Chinese Government adopted to stimulate domestic demand. Domestic demand can be divided into investment demand and consumption demand, 展开更多
关键词 high WILL China’s economic growth pushed by domestic demand and relevant measures THAN rate CPI over
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Domestic Demand-Based Economic Globalization: Strategic Choice for China to Profit from the Second Wave of Globalization
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作者 刘志彪 《China Economist》 2012年第6期68-76,共9页
China's first wave of economic globalization is characterized by its full utilization of foreign advanced, especially innovative, production factors in the domestic market to develop its innovation economy. China's ... China's first wave of economic globalization is characterized by its full utilization of foreign advanced, especially innovative, production factors in the domestic market to develop its innovation economy. China's participation in global economy can be described as fully utilizing domestic low-end production factors through foreign markets. This type of participation has been overdone. As China aims to engage in a second wave of economic globalization, the focus is to implement an in-depth globalization strategy under the condition of expanding domestic demands, namely and to develop the global economy based on domestic demands, The purpose is to achieve an economic rebalance with the world and help China out of its overcapacity predicament in weaker global economic climates. Moreover, it will bring China a chance to introduce foreign advanced factors to accelerate growth and develop innovation economy by turning economic crisis in the West into opportunities. 展开更多
关键词 domestic demands export orientation economic globalization and China's economic development
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CHINA'S GRAIN SUPPLY AND DEMAND IN THE 21ST CENTURY
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作者 Chen Xikang & Wang Zihong(Institute of Systems Science, CAS)Guo Ju-e(Shanxi Institute of Finance and Economics) 《Bulletin of the Chinese Academy of Sciences》 1996年第2期136-144,共9页
This paper makes predictions for China’s grain production and its associated supply and demand situation up to 2030 by using input-occupancy-output techniques and systems science methodology. It argues that, taking i... This paper makes predictions for China’s grain production and its associated supply and demand situation up to 2030 by using input-occupancy-output techniques and systems science methodology. It argues that, taking into account its basic situation and world grain resources, China has no other choice but to count on self-sufficiency in terms of grain supply. 展开更多
关键词 CHINA’s GRAIN sUPPLY AND demand IN THE 21sT CENTURY THAN sT
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Choosing Mandarin Senegal’s public and private schools keep up with demand for study of the Chinese language
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作者 Aly Diouf 《ChinAfrica》 2018年第12期42-43,共2页
In Dakar, Happy Kids Kindergarten has set itself an ambitious challenge: to teach Senegalese toddlers to speak Chinese. This kindergarten, located in Ngor District, boasts of being the first trilingual school in Sene... In Dakar, Happy Kids Kindergarten has set itself an ambitious challenge: to teach Senegalese toddlers to speak Chinese. This kindergarten, located in Ngor District, boasts of being the first trilingual school in Senegal. In addition to French (the country's official language) and English, the school also teaches Mandarin. With China being the world's most popu lous country and second largest economy, there is much to benefit from it this decision. 展开更多
关键词 In Choosing Mandarin senegal’s public and private schools keep up with demand for study of the Chinese language
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基于D-S证据理论的电商服装新品需求预测与订货决策研究
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作者 李凯莹 葛洪磊 +2 位作者 邬恬妮 王恒 季常恺 《物流工程与管理》 2023年第5期80-82,共3页
现有服装电商企业对新品需求预测不准确,会导致大量商品滞销或缺货,造成企业亏损。服装新品预测困难的主要原因在于其无历史数据可参考。由于证据理论具有处理多源不确定信息的能力,文中采用该理论建立需求预测模型。首先,构建证据理论... 现有服装电商企业对新品需求预测不准确,会导致大量商品滞销或缺货,造成企业亏损。服装新品预测困难的主要原因在于其无历史数据可参考。由于证据理论具有处理多源不确定信息的能力,文中采用该理论建立需求预测模型。首先,构建证据理论模型,运用D-S证据合成法则将多位专家的预测进行融合,并将预测需求量信度函数转换为概率分布;其次,通过报童模型得出最优订货量;最后,以某电商企业新品上新为例进行了算例分析。该方法可提升服装类新品需求初次预测的精准度,辅助电商企业新品订货决策。 展开更多
关键词 D-s证据理论 需求预测 订货决策 电子商务 服装新品
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中国铬矿资源特征及2021—2035年铬供需形势分析
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作者 张照志 潘昭帅 +2 位作者 车东 闫强 吴晴 《中国地质》 CAS CSCD 北大核心 2024年第4期1191-1209,共19页
【研究目的】铬矿作为我国关键性矿产之一,是支撑我国战略性新兴新兴产业发展的重要矿种。我国铬矿资源匮乏,资源禀赋不佳,产量低,长期以来,铬矿石对外依存度高。研究铬矿未来供需情况,对于铬矿资源产业良性持续发展至关重要。【研究方... 【研究目的】铬矿作为我国关键性矿产之一,是支撑我国战略性新兴新兴产业发展的重要矿种。我国铬矿资源匮乏,资源禀赋不佳,产量低,长期以来,铬矿石对外依存度高。研究铬矿未来供需情况,对于铬矿资源产业良性持续发展至关重要。【研究方法】本文对我国铬矿床地质、空间分布和资源储量等特征进行了总结,分析了我国铬矿资源开发利用的历史数据。在此基础上预测了我国铬供应量,并进一步利用铬部门消费法、人均不锈钢产量“S”形法、ARIMA模型法(不锈钢)等预测方法,分高、中、低3种情景对我国2021—2035年不锈钢产量和铬需求量进行了预测。【研究结果】(1)2021—2035年我国矿山铬年预测产量(矿石量)为15~20万t,二次铬预测产量(铬金属量)在182~284万t内;(2)在中情景下,2021—2035年我国铬需求量呈现先增后降的趋势,峰值点为2030年。2021—2030年我国人均不锈钢产量呈上升趋势,2030年到达峰值点,届时人均不锈钢产量35 kg,不锈钢产量5005万t,折铬总需求量945.39万t;之后逐渐下降,到2035年人均不锈钢产量降至30 kg,不锈钢产量4280万t,铬总需求量808.44万t。(3)2021—2035年,我国铬供需形势严峻,矿山铬对外依存度99%以上,若利用二次铬产量,则铬对外依存度降至69%以上。【结论】2021—2035年我国铬供需形势仍将严峻,缺口仍需大量进口矿石来补充。据此,提出加强铬矿地质勘查工作力度、力争实现铬矿找矿突破,重视二次铬回收利用、发展二次铬回收产业,加强铬矿产品储备、保障铬矿产品供应安全,优化铬矿产品结构,利用境外铬矿资源产品等对策结论。本文所形成的认识结论、对策建议对我国编制矿产资源规划、制定铬矿资源管理政策等具有一定的现实意义。 展开更多
关键词 铬矿资源 人均不锈钢产量 不锈钢产量"s"形法 需求预测 供需形势 矿产勘查工程 中国
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化学计量学指导原则在我国制药行业中的需求分析
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作者 赵瑜 邵学广 尹利辉 《中国药品标准》 CAS 2024年第1期5-9,共5页
目的:了解和把握我国制药行业的现状和实际需求,为《中国药典》通则“化学计量学指导原则”的建立提供依据。方法:以网络问卷的形式对制药行业从业人员化学计量学相关背景和需求进行调研。结果:我国制药行业从业人员对化学计量学指导原... 目的:了解和把握我国制药行业的现状和实际需求,为《中国药典》通则“化学计量学指导原则”的建立提供依据。方法:以网络问卷的形式对制药行业从业人员化学计量学相关背景和需求进行调研。结果:我国制药行业从业人员对化学计量学指导原则具有一定期望和需求,但人才储备情况不容乐观。结论:《中国药典》通则“化学计量学指导原则”的制订极为迫切,其作为法定依据指导分析实践活动中的数据质量控制、分析方法的建立及分析方法的验证,以保障多变量分析方法的科学性和分析结果的可靠性,这将有利于推动我国制药水平的提高。 展开更多
关键词 药典技术通则 化学计量学指导原则 近红外光谱法 过程分析技术 我国制药行业需求 人才储备
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基于“S”规律的中国钢需求预测 被引量:56
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作者 高芯蕊 王安建 《地球学报》 EI CAS CSCD 北大核心 2010年第5期645-652,共8页
本文基于人均钢消费量与人均GDP"S"形规律,对典型发达国家工业化过程钢消费量峰值年份进行截面分析,并依据我国经济增长发展目标厘定高、参考及低三种方案,解析中国未来钢需求,结论是:按高增长方案,我国人均钢消费峰值点将在2... 本文基于人均钢消费量与人均GDP"S"形规律,对典型发达国家工业化过程钢消费量峰值年份进行截面分析,并依据我国经济增长发展目标厘定高、参考及低三种方案,解析中国未来钢需求,结论是:按高增长方案,我国人均钢消费峰值点将在2015年到达,届时人均钢消费量480~500千克,消费总量6.7~7亿吨;按参考方案,我国人均钢消费峰值点将在2015-2016年到达,届时人均钢消费量430~470千克,消费总量为6~6.5亿吨;按低增长方案,我国人均钢消费峰值点将在2017-2018年到达,届时人均钢消费量400~440千克,消费总量为5.6~6.1亿吨。 展开更多
关键词 钢需求 s”形规律 预测指标 需求预测
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基于SDN的按需智能路由系统研究与验证 被引量:16
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作者 王歆平 王茜 +3 位作者 刘恩慧 马亦然 林程勇 史凡 《电信科学》 北大核心 2014年第4期8-14,共7页
软件定义网络(SDN)是一种新型的网络技术,SDN开放可编程的理念与网络管道智能化的需求能够完美地契合。在基于SDN的下一代高智能网络(S-NICE)总体架构研究的基础上进行探索,论述了S-NICE架构中的核心系统——按需智能路由系统的关键技... 软件定义网络(SDN)是一种新型的网络技术,SDN开放可编程的理念与网络管道智能化的需求能够完美地契合。在基于SDN的下一代高智能网络(S-NICE)总体架构研究的基础上进行探索,论述了S-NICE架构中的核心系统——按需智能路由系统的关键技术、系统设计、部署验证和应用场景。 展开更多
关键词 软件定义网络 智能增强型网络 基于sDN的下一代高智能网络 按需 智能路由
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基于C/S模式的粮食供需平衡监测预警系统 被引量:4
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作者 张勇 曾澜 +1 位作者 张雪 吴炳方 《计算机工程》 EI CAS CSCD 北大核心 2005年第2期214-215,218,共3页
在分析我国粮食宏观调控需求的基础上,介绍了粮食供需动态监测和预警系统的总体设计和实现方法。并对其中的关键技术问题进行了较深入的探讨。
关键词 粮食 监测预警系统 供需平衡 需求 宏观 中国 问题 关键技术 动态监测 总体设计
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GDP增速的“S”形演变轨迹-增速放缓背景下的中国矿产资源需求趋势 被引量:14
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作者 王安建 代涛 刘固望 《地球学报》 EI CAS CSCD 北大核心 2016年第5期563-568,共6页
使用美国咨商局提供的GDP 数据, 运用统计学方法, 分析了美、英、德、法、意、日、韩和中国台湾等15 个发达国家和地区1900 年以来GDP 增速变化趋势, 发现随着经济增长, GDP 增速呈现出“S”形演变轨迹, 识别出以德日为代表的快速增长... 使用美国咨商局提供的GDP 数据, 运用统计学方法, 分析了美、英、德、法、意、日、韩和中国台湾等15 个发达国家和地区1900 年以来GDP 增速变化趋势, 发现随着经济增长, GDP 增速呈现出“S”形演变轨迹, 识别出以德日为代表的快速增长型和以英美为代表的缓慢增长型两类“S”形轨迹.指出工业化中期之后GDP 增速的下降缘于第二产业增加值增速放缓和其对GDP 贡献率的快速下降, 是工业化中期之后产业结构调整和升级转型的结果.强调近年来中国GDP 增速减缓的趋势与快速增长型发达国家相同发展阶段GDP 增速减缓的“S”形轨迹相一致, 是工业化中期发展阶段大宗商品需求增速放缓过程中产业结构调整的必然.指出GDP 增速下降背景下中国主要矿产资源需求增速将放缓, 但资源消费的数量仍然会持续增长一段时间, 并保持较高的人均消费水平. 展开更多
关键词 GDP增速 s”形轨迹 矿产资源 需求趋势
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基于DirectShow的网络视频点播系统的设计与实现 被引量:3
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作者 雷文礼 任新成 +1 位作者 张栋 高瑛 《现代电子技术》 北大核心 2015年第7期31-33,38,共4页
随着计算机技术和Internet日新月异的的发展,宽带VOD视频点播技术因其良好的人机交互性和流媒体传输技术倍受教育、娱乐等行业的青睐。设计了一种基于Direct Show技术的视频点播系统,该系统采用VC编程语言实现,基于C/S架构搭建通信网络... 随着计算机技术和Internet日新月异的的发展,宽带VOD视频点播技术因其良好的人机交互性和流媒体传输技术倍受教育、娱乐等行业的青睐。设计了一种基于Direct Show技术的视频点播系统,该系统采用VC编程语言实现,基于C/S架构搭建通信网络,通过套接字实现多台客户机与服务器间的通信。测试结果表明,系统能够正常运行,视频播放流畅,可以满足网络视频点播的需求。 展开更多
关键词 视频点播 Direct sHOW C/s架构 套接字
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