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CPC模式下保量合同的在线展示广告投放策略优化
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作者 代文强 初维佳 钟婧 《中国管理科学》 CSSCI CSCD 北大核心 2024年第10期256-264,共9页
在线展示广告发展迅猛,按点击付费(cost per click,CPC)的保量合同是在线展示广告的一种重要合同形式。基于实际,在制定广告投放决策时曝光供应量通常是不确定的,其概率分布难以精确获知,仅知部分分布信息。本文利用分布鲁棒优化框架,... 在线展示广告发展迅猛,按点击付费(cost per click,CPC)的保量合同是在线展示广告的一种重要合同形式。基于实际,在制定广告投放决策时曝光供应量通常是不确定的,其概率分布难以精确获知,仅知部分分布信息。本文利用分布鲁棒优化框架,构建寻求以已知信息为特征的不确定集,并在最坏情形下寻求最优广告投放策略。建立分布鲁棒机会约束模型并给出求解算法,进行了仿真分析。数值算例结果显示,设计的广告投放优化模型和相应的求解算法具有较好的表现。 展开更多
关键词 在线展示广告 点击付费 保量 随机优化 分布鲁棒
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高大平房仓小麦保量通风对比试验 被引量:1
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作者 武国富 王云猛 王辉 《粮油仓储科技通讯》 2020年第5期33-35,共3页
采用大功率离心风机进行储粮机械通风降温容易造成粮食水分的损耗,我库利用小功率轴流风机对高大平房仓新入小麦进行了通风试验,开展储粮保量通风,可以确保储粮安全、降低通风成本,取得较好试验效果。
关键词 高大平房仓 保量 通风
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浅析调质通风与保量通风
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作者 蒋金安 《粮油食品科技》 2008年第4期30-31,共2页
通过对调质通风的现状总结,引出保量通风,然后分析了保量通风的发展过程,研究了保量通风的实质以及保量通风与调质通风的关系,最后提出,在调质通风技术尚不成熟的今天,保量通风可以作为调质通风的一种替代措施来开展。
关键词 调质通风 保量通风 现状
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保量与合理控价是建立粮食流通新体制的核心
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作者 解继成 吴雪飞 《南京经济学院学报》 1995年第2期19-21,共3页
关键词 粮食 商品流通 流通体制 保量 价格控制
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不确定曝光量下保量投放合约广告鲁棒分配优化
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作者 代文强 刘敏 隋鑫 《系统工程》 CSSCI CSCD 北大核心 2024年第2期30-38,共9页
在线广告市场中,保量投放合约广告占有重要份额。在相应的广告分配研究中,通常假设广告发布商平台在分配决策时,已知曝光量的精确值或精确概率分布,但实际决策时该值是高度不确定的。本文假设仅知曝光量部分分布信息,寻求已知部分信息... 在线广告市场中,保量投放合约广告占有重要份额。在相应的广告分配研究中,通常假设广告发布商平台在分配决策时,已知曝光量的精确值或精确概率分布,但实际决策时该值是高度不确定的。本文假设仅知曝光量部分分布信息,寻求已知部分信息的不确定集的最坏情形下的鲁棒分配方案,建立分布鲁棒机会约束模型。通过分析问题结构特征,对模型进行转化,设计了基于黄金分割搜索的风险概率凸逼近迭代算法,有效提升分配效果。最后进行数值仿真实验,验证得到的广告分配方案和相应设计算法的有效性和鲁棒性。 展开更多
关键词 展示广告 保量投放 不确定性 分布鲁棒优化 迭代算法
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数据驱动下定向展示广告保量投放鲁棒策略
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作者 隋鑫 代文强 赵博 《系统工程理论与实践》 EI CSSCI CSCD 北大核心 2024年第5期1577-1588,共12页
具有不确定性的曝光供应量给广告资源的合理分配带来了极大挑战.针对这种不确定性,本文提出了数据驱动分布鲁棒定向展示广告保量投放分配模型.首先考虑以最大化发布商收益为目标,构建对未满足需求或超出需求的部分均进行惩罚的带有机会... 具有不确定性的曝光供应量给广告资源的合理分配带来了极大挑战.针对这种不确定性,本文提出了数据驱动分布鲁棒定向展示广告保量投放分配模型.首先考虑以最大化发布商收益为目标,构建对未满足需求或超出需求的部分均进行惩罚的带有机会约束的随机规划模型.其次,利用曝光供应量的历史数据,定义Wasserstein不确定集,构建数据驱动分布鲁棒机会约束模型,该模型提出的投放策略确保在曝光供应量最坏分布情况下发布商收益最大.通过保守近似,模型可重构为易于求解的混合整数规划问题.最后,大规模样本外测试验证了模型和求解方法的可行性、有效性以及稳定性. 展开更多
关键词 数据驱动 展示广告 保量 分布鲁棒优化
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论国家对粮棉保量保价的必要与措施
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作者 刘景江 《价格理论与实践》 CSSCI 北大核心 1994年第10期18-23,共6页
论国家对粮棉保量保价的必要与措施刘景江去冬今春,我国南方沿海一些省市的粮价曾一度大幅度上涨,后经中央及时采取措施,粮价才得到平抑。今年上半年,因去年棉花产量降到6年来的最低点,全国出现了棉花价格暴涨。到5月份,棉花市... 论国家对粮棉保量保价的必要与措施刘景江去冬今春,我国南方沿海一些省市的粮价曾一度大幅度上涨,后经中央及时采取措施,粮价才得到平抑。今年上半年,因去年棉花产量降到6年来的最低点,全国出现了棉花价格暴涨。到5月份,棉花市场价涨到国家牌价的3倍,每吨棉花为... 展开更多
关键词 粮食 棉花 保量保价 价格
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POPULATION AND CONSERVATION OF BLACK CRESTED GIBBONS ( Hylobates concolor jingdongensis ) IN WULIANG NATURE RESERVE,JINGDONG,YUNNAN 被引量:5
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作者 蒋学龙 王应祥 《Zoological Research》 CAS CSCD 1999年第6期421-425,共5页
Population estimates of black crested gibbons in Wuliang Nature Reserve,Jingdong,Yunnan,China,with two techniques,average group density total area and average home rang forest coverage,produced quite similar result... Population estimates of black crested gibbons in Wuliang Nature Reserve,Jingdong,Yunnan,China,with two techniques,average group density total area and average home rang forest coverage,produced quite similar results.The population was estimated around 115 groups in the Reserve.The paper also discussed the conservation problems of the Reserve.At present,the main threat to the gibbons is habitat fragmentation and population isolation.Thus,it is urgent to prohibit hunting and protect the habitat and forest corridors or habitat bridges. 展开更多
关键词 Hylobates concolor jingdongensis POPULATION CONSERVATION Wuliang Natural Reserve
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Urban street network capacity reliability 被引量:4
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作者 程琳 李强 +1 位作者 王京元 王炜 《Journal of Southeast University(English Edition)》 EI CAS 2004年第2期235-239,共5页
A reliability measure of network capacity under node capacities is introduced, using the concept of network reserve capacity, and compared with that based on link capacities. The node capacities should be considered i... A reliability measure of network capacity under node capacities is introduced, using the concept of network reserve capacity, and compared with that based on link capacities. The node capacities should be considered in to the reliability analysis of urban street networks. Providing that every origin-destination (OD) pair have a uniform growth or decline in its OD demand, whereas relaxing this limitation can yield pictures regarding the spatial distribution of the demand pattern with non-uniform change, which can be especially useful in individual zone land-use development plans. 展开更多
关键词 Computer simulation PROBABILITY RELIABILITY TRANSPORTATION
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加油站布局的构思(上) 被引量:4
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作者 陈红 《石油库与加油站》 2001年第5期27-31,共5页
对加油站建设的选址问题进行了较为详细的论述,并对加油站功能区的设置进行了探讨。选址的原则是加油站应在加油需求量大,交通便利,符合安全规范、城乡规划和环保要求的地方。
关键词 加油站 布局 选址 辐射选址法 保量选址法
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轴流风机冬季降温及保温通风实验 被引量:1
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作者 臧波 梁庆文 宋永久 《粮食加工》 2008年第4期71-73,共3页
高大平房仓冬季利用轴流风机进行降温通风,具有操作简单灵活、受条件限制小、能耗低等优点,现已被各仓储单位普遍应用。抓住冬季自然冷源丰富时机,适当选择通风时大气相对湿度,利用轴流风机对粮堆进行通风降温,使平均粮温降至4.0~6.0℃... 高大平房仓冬季利用轴流风机进行降温通风,具有操作简单灵活、受条件限制小、能耗低等优点,现已被各仓储单位普遍应用。抓住冬季自然冷源丰富时机,适当选择通风时大气相对湿度,利用轴流风机对粮堆进行通风降温,使平均粮温降至4.0~6.0℃,最大限度地降低储粮机械通风的单位能耗、原有粮食水分损耗,实现降温、保量通风,为准低温储粮奠定基础。 展开更多
关键词 轴流风机 保量降温通风 结露 能耗
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Research on development of urban taxi supply based on influence factors classification 被引量:2
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作者 陈景旭 王炜 +1 位作者 陈学武 沈劲石 《Journal of Southeast University(English Edition)》 EI CAS 2013年第2期194-198,共5页
In order to determine the regulations of the development of taxi supply under entry regulations in Chinese cities, an improved neural network model is applied to find the particular years when the government artificia... In order to determine the regulations of the development of taxi supply under entry regulations in Chinese cities, an improved neural network model is applied to find the particular years when the government artificially puts new taxis into the market, and then extract the political influence from the taxi supply. The model is also utilized to study the relationships between the adjusted taxi supply and non-policy factors. A case study of Nanjing city is conducted. The results show that 2001 and 2007 are the particular years that the Nanjing government artificially put new taxis into its taxi market, which is in accordance with the five-year plan of China and the local development plans. The results also show that the improved neural network model has a good performance in expositing the evolution of adjusted taxi supply related to non-policy factors. 展开更多
关键词 taxi supply neural network model policy year influence factor
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小学数学简约课堂教学策略探究 被引量:5
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作者 张丽平 《华夏教师》 2020年第19期76-77,共2页
简约化教学不是盲目的偷工减料,而是以先进的理念为支撑,通过精简程序,去粗存精,删减重复的枝节,剪除赘余的环节,让教学设计与实践轻装上阵,以简明扼要的形式揭示出丰富的数学内涵,从而实现大巧若拙,外松内紧的数学课堂。
关键词 减负 数学 体质 保量 精练 推导
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Probabilistic method and its application for evaluating carbonation life of newly-built concrete structures 被引量:2
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作者 巴明芳 钱春香 黄雷 《Journal of Southeast University(English Edition)》 EI CAS 2010年第4期578-581,共4页
In order to evaluate the carbonation life of newly-built concrete structures,two kinds of nondestructive methods are adopted to test the thickness of the concrete cover and the ultrasonic velocity of two newly-built t... In order to evaluate the carbonation life of newly-built concrete structures,two kinds of nondestructive methods are adopted to test the thickness of the concrete cover and the ultrasonic velocity of two newly-built tunnel structures.Simultaneously a probabilistic method is proposed based on the relationship between the accelerated carbonation rate and the ultrasonic velocity.This proposed method is applied to evaluate the carbonation related lives of two newly-built tunnels and the results indicate that even under nearly the same environment and CO2 combining conditions,there exits a big difference in the probabilistic carbonation lives between the two tunnels;i.e.,the probabilistic lives of Tunnel A and Tunnel B are 94.0% and 82.3% and the corresponding maximum discrepancies are 11.6% and 27.0%,respectively.Thus,it can be concluded that the scattered quality of the concrete cover is attributed to the differences in construction technique,which eventually leads to the diversity in the evaluated probabilistic carbonation lives of the two tunnels. 展开更多
关键词 probabilistic carbonation life newly-built structure concrete-cover quality
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Effects of Super Absorbent Polymers on Yield and Water-saving and Drought-escaping Mechanism in Spring Maize 被引量:11
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作者 唐海明 汤文光 +1 位作者 肖小平 杨光立 《Agricultural Science & Technology》 CAS 2009年第4期112-116,共5页
The effects of super absorbent polymers (SAP) on yield as well as water-saving and drought-escaping mechanism in spring maize in the seasonal drought region were studied. As shown by the results, during the seasonal... The effects of super absorbent polymers (SAP) on yield as well as water-saving and drought-escaping mechanism in spring maize in the seasonal drought region were studied. As shown by the results, during the seasonal drought in southern China, SAP treatment promoted the soil moisture, improved the capability of absorption and transportation of roots, promoted physiological and biochemical functions, increased the chlorophyll content, photosynthetic rate and intercellular CO2 concentration, and reduced the stomatal conductance and transplre.tion rate. As a result, the economic characters of spring maize were improved, and the yield was increased. 展开更多
关键词 Super absorbent polymer Spring maize Water-saving and drought-escaping mechanism
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《选煤楼装车系统的改造》研究报告
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作者 李海斌 《科技信息》 2009年第2期283-283,共1页
通过具体问题具体分析对装车系统进行改造,以符合万吨列车的装车要求,此项目完成后具有操作方便、安全可靠,同时避免了皮带的频繁启动,延长了皮带、电机、减速箱等的使用寿命,可在同类情况下推广使用。
关键词 按时 保质 保量 装车 提高 效率
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Admission Control Based on QoS for Third Generation Broadband Mobile Communication Systems
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作者 侯春萍 常倩 +1 位作者 曹达仲 范仲方 《Transactions of Tianjin University》 EI CAS 2002年第2期110-113,共4页
In this paper, a novel admission scheme is proposed which provides high degrees of quality of service (QoS) guarantees for multimedia traffic carried in mobile networks. The proposed scheme combines the admission cont... In this paper, a novel admission scheme is proposed which provides high degrees of quality of service (QoS) guarantees for multimedia traffic carried in mobile networks. The proposed scheme combines the admission control and bandwidth reservation to guarantee QoS requirements. It considers both local information and remote information to determine whether to accept or reject a connection. In order to embody the characteristics of the algorithms proposed in the article, two traditional algorithms of admission control are used for comparison. In the end of the paper the simulation analyses are given and the results show that the proposed algorithm can adjust the bandwidth according to the current status of networks and decrease the probability of connections forcibly dropped. The most important thing is that the algorithm is based on the multimedia communications and can guarantee the QoS of real time connections through decreasing the bandwidth of non real time connections. 展开更多
关键词 broadband mobile networks admission control quality of service guarantee
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Characteristics of natural Japanese yew population in Muling Nature Reserve of Heilongjiang Province,China 被引量:1
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作者 刘彤 周志强 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第2期132-134,共3页
The scalar of Japanese yew (Taxus cuspidata) population and the relationship between individual distribution and site factors were analyzed according to investigating data in 74 sample belts with a total sampled are... The scalar of Japanese yew (Taxus cuspidata) population and the relationship between individual distribution and site factors were analyzed according to investigating data in 74 sample belts with a total sampled area of 436.872 hm2 in Muling Nature Reserve. The result showed that the distribution rules of Japanese yew population were correlated to elevation, slope position, slope aspect and slope gradient. The optimal distribution range in elevation for the natural Japanese yew population is at the attitudes of 700-800 m. The amounts of Japanese yew individuals on shady slope were more than those on sunny slope. On top slope and mid-slope, the individual amounts of Japanese yew are more than those on toe slope. Most of Japanese yew individuals occurred on slope gradient of less than 15. The scalar of the population was decreased with the slope gradient increasing. 展开更多
关键词 Japanese yew Taxus cuspidate Muling Nature Reserve POPULATION
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QUALITY ASSURANCE INFORMATION SYSTEM FOR AGILE MANUFACTURING
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作者 孙蓓蓓 钟秉林 +2 位作者 崔敏 黄仁 A kif A.Bulgak 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2000年第1期71-77,共7页
The customer driven dynamic global market and geographical distribution of collaborating partners bring new challenges to the development of quality assurance information system (QAIS) for agile manufacturing. With re... The customer driven dynamic global market and geographical distribution of collaborating partners bring new challenges to the development of quality assurance information system (QAIS) for agile manufacturing. With recent dramatic advances in information technology, firstly the requirements of QAIS are examined in agile manufacturing environment, then a new implementation framework of a distributed QAIS is presented, where a deve loping environment of QAIS is established and some critical techniques are studied. Finally a prototype system based on world wide web (WWW) is accomplished. 展开更多
关键词 QUALITY quality control information system quality assurance agile manufacturing INTERNET INTRANET
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A Study of Fructification Quantitative Characteristics of Spartina alterniflora Lossel in Mangroves 被引量:7
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作者 覃盈盈 梁士楚 《Agricultural Science & Technology》 CAS 2009年第1期101-104,共4页
[Objective] The countermeasure on the number of fructification of Spartina alterniflora in the period of sexual reproduction and the component of seed yielding construction was explored.[Method] The Spartina altemiflo... [Objective] The countermeasure on the number of fructification of Spartina alterniflora in the period of sexual reproduction and the component of seed yielding construction was explored.[Method] The Spartina altemiflora in Mangroves conservation zone located at Hepu of Guangxi being taken as experimental material, its morphological and quantitative characteristics, as well as the weight of 100 full seeds at maturity stage in three different growth conditions( clay, loam and sand) were studied. [ Results] The results showed that Spartina alterniflora had the best growth pattern in the loam. The morphological factors of fructification of S. altemiflora grown in sand were larger then in others. In the three growth conditions the order of quantitative characteristics of fructification of S. alterniflora was clay 〉 sand 〉 loam and the seeds in spikelet at top position were more maturity than those at the button position. [ Conclusion] In good condition, the Spartina altemiflora growth was vigor but the ratio of seed-setting was low. 展开更多
关键词 Spartina altemiflora Different habitat FRUCTIFICATION Quantitative characteristics
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