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基于Multi-index LQ与CIC指数的集成评估框架 被引量:3
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作者 张志明 曹钰 《合肥工业大学学报(自然科学版)》 CAS CSCD 北大核心 2009年第5期716-719,共4页
将多指标区位商计算和工业集群竞争力评价相结合,生成集成的工业集群竞争力评估框架,运用统计数据,可对我国区域工业集群现状及工业集群竞争力水平进行分析。结果表明,区域工业经济存在4种类型,即集聚的竞争优势产业、集聚的竞争劣势产... 将多指标区位商计算和工业集群竞争力评价相结合,生成集成的工业集群竞争力评估框架,运用统计数据,可对我国区域工业集群现状及工业集群竞争力水平进行分析。结果表明,区域工业经济存在4种类型,即集聚的竞争优势产业、集聚的竞争劣势产业、非集聚的竞争优势产业和非集聚的竞争劣势产业;据此,我国区域工业经济的支柱产业和主导产业可以被确定。 展开更多
关键词 工业集群 多指标区位商 工业集群竞争力 集成评估框架
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Multi-index analysis of the melting process of laterite metallized pellet 被引量:1
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作者 Yun Wang Rong Zhu +3 位作者 Kai-lu Tu Guang-sheng Wei Shao-yan Hu Hong Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2018年第12期1423-1430,共8页
Herein, a multi-index analysis of the nickel content of an alloy, output rate of the alloy, nickel recovery rate, and iron recovery rate during the melting of laterite metallized pellets was performed. The thermodynam... Herein, a multi-index analysis of the nickel content of an alloy, output rate of the alloy, nickel recovery rate, and iron recovery rate during the melting of laterite metallized pellets was performed. The thermodynamic reduction behavior of oxides such as NiO, FeO, Fe_3 O_4, and Cr_2 O_3 was studied using the FactSage software, which revealed that SiO_2 is not conducive to the reduction of iron oxides, whereas the addition of basic oxides such as CaO and MgO is beneficial for the reduction of iron oxides. On the basis of a comprehensive analysis to achieve greater nickel recovery and lower iron recovery rates, the optimum experimental parameters in the orthogonal experiment were A3 B1 C3(t = 30 min, C/O = 0.4, R = 1.2); the indicators wNi, φalloy, ηNi, and ηFe had values of 15.0 wt%, 12.1%, 44.9%, and 96.4%, respectively. In single-factor experiments, increasing basicity(R) substantially improved the separation effect in the low-basicity range 0.5 ≤ R ≤ 0.8 but not in the high-basicity range 0.8 ≤ R ≤ 1.2. Similar results were obtained for the effect of the C/O ratio. Moreover, the recovery rate of nickel increased with increasing recovery rate of iron. 展开更多
关键词 MELTING and separation LATERITE metallized PELLET multi-index ANALYSIS BASICITY carbon-to-oxygen ratio
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Joint Optimization of Satisfaction Index and Spectrum Efficiency with Cache Restricted for Resource Allocation in Multi-Beam Satellite Systems 被引量:4
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作者 Pei Zhang Xiaohui Wang +1 位作者 Zhiguo Ma Junde Song 《China Communications》 SCIE CSCD 2019年第2期189-201,共13页
Dynamic resource allocation(DRA) is a key technology to improve system performances in GEO multi-beam satellite systems. And, since the cache resource on the satellite is very valuable and limited, DRA problem under r... Dynamic resource allocation(DRA) is a key technology to improve system performances in GEO multi-beam satellite systems. And, since the cache resource on the satellite is very valuable and limited, DRA problem under restricted cache resources is also an important issue to be studied. This paper mainly investigates the DRA problem of carrier resources under certain cache constraints. What's more, with the aim to satisfy all users' traffic demands as more as possible, and to maximize the utilization of the bandwidth, we formulate a multi-objective optimization problem(MOP) where the satisfaction index and the spectrum efficiency are jointly optimized. A modified strategy SA-NSGAII which combines simulated annealing(SA) and non-dominated sorted genetic algorithm-II(NSGAII) is proposed to approximate the Pareto solution to this MOP problem. Simulation results show the effectiveness of the proposed algorithm in terms of satisfaction index, spectrum efficiency, occupied cache, and etc. 展开更多
关键词 GEO multi-BEAM satellite system dynamic resource ALLOCATION SA-NSGAII CACHE SATISFACTION index spectrum efficiency
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Presentation of a multi-index clustering technique for the mathematical programming of block-cave scheduling
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作者 Farshad Nezhadshahmohammad Yashar Pourrahimian Hamid Aghababaei 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2018年第6期941-950,共10页
Long-term planning is one of the most important stages that determines the distribution of cash flows over the mine life and the feasibility of the project. However, it is not feasible in block caving to generate a pr... Long-term planning is one of the most important stages that determines the distribution of cash flows over the mine life and the feasibility of the project. However, it is not feasible in block caving to generate a production schedule that will provide optimal operating strategies without considering geotechnical constraints. This paper develops a mixed-integer linear programming(MILP) model to optimize the extraction sequence of drawpoints over multiple time horizons of block-cave mines with respect to the draw control systems. A multi-similarity index clustering technique to solve the MILP model in a reasonable time is also presented. Application and comparison of production scheduling based on the draw control system and clustering technique are illustrated using 325 drawpoints over 15 periods. The results show a significant reduction in the size of the MILP model, and in the time required to solve it. 展开更多
关键词 PRODUCTION SCHEDULING Block-cave mining multi-similarity index clustering DRAW control system PRODUCTION rate curve
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Kind of Fuzzy Method Determining Index Weight on Multi-Objctive Decision Making
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作者 程国明 黄侃 《International Journal of Mining Science and Technology》 SCIE EI 1999年第2期211-214,共4页
Based on fuzzy characteristic of dicision-making thought, matrix of priority relation has been introduced and blurrized. A kind of fuzzy method, which is to determine the index weight on multi-objective decision makin... Based on fuzzy characteristic of dicision-making thought, matrix of priority relation has been introduced and blurrized. A kind of fuzzy method, which is to determine the index weight on multi-objective decision making, has been put forward by means of the sequence root method for analysis of hierarchical process (AHP). Using this method an example which is to define the index weigbt on multi-objective decision making in thc scheme optimization of mine design has been given. 展开更多
关键词 fuzzy method index weight multi-OBJECTIVE decision making CONSISTENCY MINE design
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Application of multi-dimensional index matching in Pub/Sub system
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作者 SONG Yu WU Yan QIAO Ling-ling 《通讯和计算机(中英文版)》 2009年第12期9-13,共5页
关键词 匹配算法 子系统 发布/订阅 酒吧 多维 应用 事件约束 相匹配
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Study on Multi-effect Time Parameters of Ergonomic Validity Index in Low-carbon Residential Kitchen
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作者 Jun Ji Hong Jin 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第5期52-58,共7页
In the study on functional low-carbon ergonomic validity in buildings,ergonomic validity is different from resource validity which is easy for quantitative analysis. To eliminate the complexity and uncertainty impacts... In the study on functional low-carbon ergonomic validity in buildings,ergonomic validity is different from resource validity which is easy for quantitative analysis. To eliminate the complexity and uncertainty impacts of human factors on quantitative study,it proposes a method of building a parameter of ergonomic validity—multi-effect time by using cardiotachometer to record heart rate change,being used to evaluate the functional low-carbon ergonomic validity targeting at the ontological characteristics of kitchen. This method is used to determine the physical consumption intensity( multi-effect) through heart rate incremental relation based on the principles of physiology and ergonomics,and to confirm the ergonomic validity of environmental factors by the time to complete standard work as well as multi-effect quantitative analysis. The test results show that,under the kitchen operating conditions,the multi-effect( ME) can properly reflect the real-time status of the operator and is easily operated; the parameters obtained are not significantly related to the physiological status of the operator,and multi-effect time( MT) is sensitive to the physical consumption brought about to the operator due to kitchen environmental factors; thus,it can be taken as an objective index,which is simple and easy to operate in residential kitchen functional low-carbon evaluation. 展开更多
关键词 functional low-carbon human factors ergonomic validity index basal heart rate increment ratio multi-effect time of kitchen work
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库存管理模拟Multi-Agent建模方法研究 被引量:5
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作者 贾红雨 陈燕 +1 位作者 胡松筠 汪蓓蓓 《系统仿真学报》 CAS CSCD 北大核心 2006年第z2期73-76,共4页
针对物流库存管理决策问题,把客户满意度作为考核系统效率的关键指标之一,研究库存系统中的出入库量、服务水平、库存规则以及各种成本等要素之间的关系,提出一种基于多智能体的系统模拟建模方法。建立库存管理模拟Multi-Agent系统,模... 针对物流库存管理决策问题,把客户满意度作为考核系统效率的关键指标之一,研究库存系统中的出入库量、服务水平、库存规则以及各种成本等要素之间的关系,提出一种基于多智能体的系统模拟建模方法。建立库存管理模拟Multi-Agent系统,模拟运行结果可以给出库存补进建议,帮助管理人员进行决策。研究了一个应用实例,利用具体历史数据对建模方法和模型进行了验证和分析。 展开更多
关键词 模拟建模 多智能体 库存管理 客户满意度
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电子商务环境下基于Multi-Agent的B2B信任评价模型研究 被引量:7
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作者 孙华梅 邹维娜 《运筹与管理》 CSSCI CSCD 北大核心 2014年第5期231-236,共6页
电子商务的发展为企业的合作提供了机遇,同时也带来了诸多挑战。企业在合作过程中表现出了许多问题,例如信任的缺失,缺乏可以合理全面测量企业信任度的方法等。本文运用Multi-agent技术,建立了结合企业基本信息的声誉评价Agent和结合特... 电子商务的发展为企业的合作提供了机遇,同时也带来了诸多挑战。企业在合作过程中表现出了许多问题,例如信任的缺失,缺乏可以合理全面测量企业信任度的方法等。本文运用Multi-agent技术,建立了结合企业基本信息的声誉评价Agent和结合特定交易信息的单次交易评价Agent的信任评价指标体系,并在此基础上构建了基于Multi-agent的B2B信任评价模型,最后进行了仿真实验。论文的研究对于企业在电子商务环境下选择合适的合作伙伴,解决合作中的信任问题,适应电子商务发展的需要具有一定的意义。 展开更多
关键词 信任评价指标 B2B信任评价模型 电子商务
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低复杂度的Multi-hCPM调制指数同步算法 被引量:2
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作者 杨春 钟声 +1 位作者 谢顺钦 张健 《兵工自动化》 2015年第9期45-50,共6页
针对多指数连续相位调制信号的调制指数同步困难且算法复杂的问题,提出一种实现结构相对简单的低复杂度的Multi-h CPM调制指数同步算法。基于最大似然准则获得Multi-h CPM信号的调制指数同步误差和残留定时误差的联合估计,分别利用残留... 针对多指数连续相位调制信号的调制指数同步困难且算法复杂的问题,提出一种实现结构相对简单的低复杂度的Multi-h CPM调制指数同步算法。基于最大似然准则获得Multi-h CPM信号的调制指数同步误差和残留定时误差的联合估计,分别利用残留定时误差近似为零的性质与滤波器冲击响应量化函数来降低算法的复杂度,并进行性能仿真验证。仿真结果表明:该算法调制指数同步误差估计的性能良好,适用于全响应和部分响应的Multi-h CPM信号。 展开更多
关键词 多指数连续相位调制 调制指数 同步 低复杂度
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GC-MS结合电子鼻技术对不同茶区茉莉花茶香气的差异比较 被引量:3
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作者 李璐 尹礼国 +4 位作者 陆安霞 王秋卫 陈丽 赵先明 黄彤 《现代食品科技》 CAS 北大核心 2024年第2期302-311,共10页
为探究不同产区茉莉花茶香气差异,采用气相色谱-质谱(GasChromatography-Mass Spectrometry,GC-MS)结合电子鼻(Electronic Nose,E-nose)技术对西南、华南、江南三大茶区的8种茉莉花茶进行香气研究。结果表明,8个样品共鉴定出香气成分58... 为探究不同产区茉莉花茶香气差异,采用气相色谱-质谱(GasChromatography-Mass Spectrometry,GC-MS)结合电子鼻(Electronic Nose,E-nose)技术对西南、华南、江南三大茶区的8种茉莉花茶进行香气研究。结果表明,8个样品共鉴定出香气成分58种,其中西南、江南、华南茶区分别为45种、51种、47种。江南茶区香气化合物总量最高。共有香气成分主要包括邻氨基苯甲酸甲酯、顺式-3-己烯醇苯甲酸酯、乙酸苄酯、水杨酸甲酯、芳樟醇、吲哚等。其中水杨酸甲酯在江南茶区含量最高(22.32μg/g),分别较华南、西南茶区高33.96%、68.01%;邻氨基苯甲酸甲酯(67.39μg/g)和吲哚(43.84μg/g)含量在华南茶区最高。茉莉花茶香气评价指数(JasmineTea Flavor Index,JTF index)分析表明西南茶区样品等级最高。香气聚类分析将共有香气成分分为3类,分别呈花香、茉莉花香和草木香。通过电子鼻技术可知样品香气物质变化与硫化物、碳氢化合物、芳香化合物有关,并能有效区别样品香气。综上,三大茶区样品香气种类差异不明显,但各香气成分含量差异显著(P<0.05),江南和华南茶区的样品特征性香气成分含量较高,西南茶区样品综合指数高。 展开更多
关键词 香气 茉莉花茶 气相色谱-质谱法(GC-MS) 电子鼻 茉莉花茶香气评价指数(JTF index)
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熵权-正交法优化赤苍藤中多糖、多酚和黄酮的提取工艺
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作者 陆玉婷 毕明月 +3 位作者 卓燊 李有娟 陆苑 伍善广 《广西科技大学学报》 CAS 2024年第1期123-130,共8页
优化赤苍藤中多糖、多酚和黄酮的提取工艺,为综合评价其质量提供参考。以赤苍藤茎为研究对象,采用酶解法,选取适宜的酶质量分数、酶解p H、酶解温度及酶解时间为考察因素,以多糖、多酚、黄酮和浸膏提取率为评价指标。基于熵权法客观赋... 优化赤苍藤中多糖、多酚和黄酮的提取工艺,为综合评价其质量提供参考。以赤苍藤茎为研究对象,采用酶解法,选取适宜的酶质量分数、酶解p H、酶解温度及酶解时间为考察因素,以多糖、多酚、黄酮和浸膏提取率为评价指标。基于熵权法客观赋权结合L_9(3~4)正交试验,优选赤苍藤的多指标提取工艺。最佳提取工艺条件为:酶质量分数4%,酶解p H值6.0,酶解温度50℃,酶解时间45 min。考察多指标后,确认优选的提取工艺稳定可行,可为赤苍藤的质量评价提供实验依据。 展开更多
关键词 赤苍藤 熵权法 酶解法 多指标评价 提取工艺
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一测多评法测定法制半夏曲中11种成分含量及其GRA、EW-TOPSIS质量评价
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作者 舒波 雷果平 袁斌 《医药导报》 CAS 北大核心 2024年第7期1120-1126,共7页
目的采用一测多评(QAMS)法同时测定法制半夏曲中肌苷、鸟苷、腺苷等11种成分含量,并建立其灰色关联度分析(GRA)联合熵权逼近理想解排序分析法(EW-TOPSIS)综合质量评价方法。方法采用Shimadzu C 18色谱柱;乙腈-0.5%醋酸为流动相,梯度洗脱... 目的采用一测多评(QAMS)法同时测定法制半夏曲中肌苷、鸟苷、腺苷等11种成分含量,并建立其灰色关联度分析(GRA)联合熵权逼近理想解排序分析法(EW-TOPSIS)综合质量评价方法。方法采用Shimadzu C 18色谱柱;乙腈-0.5%醋酸为流动相,梯度洗脱,流速1.0 mL·min-1;检测波长254和290 nm。以对甲氧基肉桂酸乙酯为内参比物质,计算其他10个成分的相对校正因子(RCF),测定各成分含量。采用GRA联合EW-TOPSIS模型对法制半夏曲进行综合质量评价。结果法制半夏曲中11种成分在一定浓度范围内线性关系良好,相关系数均>0.999;平均加样回收率96.94%~100.12%(RSD<2.0%,n=9);QAMS与外标法(ESM)实测值无明显差异。GRA模型相对关联度0.2903~0.6187,EW-TOPSIS模型相对接近度0.2114~0.6343;GRA和EW-TOPSIS模型综合评价结果基本一致。结论QAMS法便捷、准确,可用于法制半夏曲多指标成分定量控制,GRA联合EW-TOPSIS模型可用于法制半夏曲综合质量评价。 展开更多
关键词 法制半夏曲 一测多评法 多指标成分 相对校正因子 灰色关联度分析 熵权-逼近理想解排序法 质量评价
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Multi-Agent技术在车间调度中的应用 被引量:7
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作者 王雪辉 李世杰 张玉芝 《河北工业大学学报》 CAS 2005年第2期105-109,共5页
根据车间调度的动态复杂性,本文提出了一种将多智能体(Multi-Agent)技术应用于设备调度的模型.整个调度系统建立于任务Agent,资源Agent和协调Agent基础上,通过招标——投标机制及奖罚制度完成车间调度,调度过程的优化通过一个综合指标... 根据车间调度的动态复杂性,本文提出了一种将多智能体(Multi-Agent)技术应用于设备调度的模型.整个调度系统建立于任务Agent,资源Agent和协调Agent基础上,通过招标——投标机制及奖罚制度完成车间调度,调度过程的优化通过一个综合指标来实现.经过仿真实例验证,本系统很好的实现了多目标优化,并且保证了整个系统朝着全局最优的方向发展. 展开更多
关键词 多智能体 招标-投标 奖罚制度 综合指标
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中亚地区2001-2020年250 m及2020年30 m分辨率植被生长季NDVI数据集
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作者 高超 任小丽 +4 位作者 曾纳 刘畅 张心昱 张黎 何洪林 《中国科学数据(中英文网络版)》 CSCD 2024年第3期1-11,共11页
中亚地区是北半球最大的干旱和半干旱区,其生态环境十分脆弱,对全球气候变化的响应较为敏感。由于该区域的特殊地理位置,维护该区域生态系统的稳定对全球经济社会发展至关重要。植被具有重要的生态环境指示作用,其时空分布格局和变化趋... 中亚地区是北半球最大的干旱和半干旱区,其生态环境十分脆弱,对全球气候变化的响应较为敏感。由于该区域的特殊地理位置,维护该区域生态系统的稳定对全球经济社会发展至关重要。植被具有重要的生态环境指示作用,其时空分布格局和变化趋势是评估区域生态状况的重要指标。归一化植被指数(Normalized Difference Vegetation Index,NDVI)作为研究植被最常用的遥感指数之一,能够表征植被的时空变化特征。本数据集利用MODIS13Q1产品生成了中亚地区2001–2020年长时间序列空间分辨率为250 m的生长季均值NDVI数据,并使用基于规则的分段回归Cubist算法,结合Landsat数据,融合得到了能够更好表征地物细节的30 m空间分辨率的2020年生长季均值NDVI数据。同时,本数据集从数据源的质控,模型训练优化,以及模型独立验证三个方面对数据产品进行质量控制,以确保数据的精度和可靠性。本数据集的生成为中亚地区植被动态变化和空间格局的分析提供了有力的数据支持。 展开更多
关键词 归一化植被指数 中亚 多源遥感数据融合 遥感产品
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多指标综合评分法结合Box-Behnken响应面法优选栀子茯苓压片糖果的提取工艺
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作者 邓刚 梁可文 蒋婳影 《化工科技》 CAS 2024年第3期40-45,共6页
以提取液中栀子苷含量及干膏率作为考察指标,在单因素试验基础上采用直接回流提取法、多指标综合评分法结合Box-Behnken响应面法考察了乙醇浓度、提取时间和料液比3个因素对提取工艺的影响。结果表明,制剂的最佳提取工艺为乙醇浓度75%,... 以提取液中栀子苷含量及干膏率作为考察指标,在单因素试验基础上采用直接回流提取法、多指标综合评分法结合Box-Behnken响应面法考察了乙醇浓度、提取时间和料液比3个因素对提取工艺的影响。结果表明,制剂的最佳提取工艺为乙醇浓度75%,提取时间120 min,料液比17倍,栀子苷平均含量为3.17%,平均干膏率为11.33%,综合评分平均值为98.30(n=3,RSD=0.18%)。该工艺合理可行,有效成分提取率高,适合大规模生产。 展开更多
关键词 栀子茯苓压片糖果 多指标综合评分法 Box-Behnken响应面法 提取工艺
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基于FBG和F-P的温度和折射率双参量传感器
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作者 姚国珍 宗子天 +3 位作者 吴玉章 李炳峰 颜炳欣 尚秋峰 《半导体光电》 CAS 北大核心 2024年第3期349-355,共7页
提出了一种由单模布拉格光栅和多模Fabry-Perot腔级联而成的温度和折射率双参量传感器。对多模光纤的末端采用氢氟酸进行腐蚀,在腐蚀后形成的凹陷处填充紫外胶,从而形成Fabry-Perot腔。Fabry-Perot腔和单模光纤布拉格光栅级联后,构成最... 提出了一种由单模布拉格光栅和多模Fabry-Perot腔级联而成的温度和折射率双参量传感器。对多模光纤的末端采用氢氟酸进行腐蚀,在腐蚀后形成的凹陷处填充紫外胶,从而形成Fabry-Perot腔。Fabry-Perot腔和单模光纤布拉格光栅级联后,构成最终的传感结构。Fabry-Perot腔对温度和折射率敏感,而光纤布拉格光栅对温度敏感而对折射率不敏感。利用上述特性,采用灵敏度矩阵法可实现对温度和折射率的同时测量。实验结果表明,传感器的温度和折射率灵敏度分别为-0.4832nm/℃和-508.64pm/RIU。该传感器具有制作工艺简单、结构紧凑、成本低、灵敏度高的优点,有很好的应用前景。 展开更多
关键词 温度和折射率传感 Fabry-Perot腔 光纤布拉格光栅 多模光纤
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Multi-features Based Approach for Moving Shadow Detection 被引量:4
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作者 周宁 周曼丽 +1 位作者 许毅平 方宝红 《Journal of Donghua University(English Edition)》 EI CAS 2004年第6期76-80,共5页
In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving... In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving visual object detection. The major novelty of the shadow suppression is the integration of several features including photometric invariant color feature, motion edge feature, and spatial feature etc. By modifying process for false shadow detected, the averaging detection rate of moving object reaches above 90% in the test of Hall-Monitor sequence. 展开更多
关键词 MOVING SHADOW detection multi - features MOVING OBJECT DETECTION
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The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) 被引量:42
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作者 Xiang-Qun Cui Yong-Heng Zhao +52 位作者 Yao-Quan Chu Guo-Ping Li Qi Li Li-Ping Zhang Hong-Jun Su Zheng-Qiu Yao Ya-Nan Wang Xiao-Zheng Xing Xin-Nan Li Yong-Tian Zhu Gang Wang Bo-Zhong Gu A-Li Luo Xin-Qi Xu Zhen-Chao Zhang Gen-Rong Liu Hao-Tong Zhang De-Hua Yang Shu-Yun Cao Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Ying Chen Jia-Ru Chu Lei Feng Xue-Fei Gong Yong-Hui Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Lei Jia Fang-Hua Jiang Xiang Jiang Zi-Bo Jiang Ge Jin Ai-Hua Li Yan Li Ye-Ping Li Guan-QunLiu Zhi-Gang Liu Huo-Ming Shi Zheng-Hong Tang Qing-Sheng Tao Xiang-Yan Yuan Chao Zhai Jing Zhang Yan-Xia Zhang Yong Zhang Ming Zhao Fang Zhou Guo-Hua Zhou Jie Zhu Si-Cheng Zou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第9期1197-1242,共46页
The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effecti... The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effective aperture of 3.6 m–4.9 m) and a wide field of view (FOV) (5°). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror’s surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67m×6.05 m) and active Schmidt mirror (5.74m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects. 展开更多
关键词 techniques: wide field telescope - active optics - multi fiber - spectroscopy survey - data reduction
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基于多指标成分定量、化学计量学、EW-TOPSIS分析的白术厚朴合剂质量评价研究
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作者 陈飞 魏谭军 +5 位作者 肖成 魏旭 徐飞 王春龙 李先海 王毅 《湖南中医药大学学报》 CAS 2024年第3期401-407,共7页
目的以10种成分为指标,建立白术厚朴合剂HPLC定量分析方法,联合化学计量学及熵权优劣解距离法(EW-TOPSIS)对其质量进行综合评价。方法以75%甲醇提取液为样品,采用Agilent TC-C18色谱柱,乙腈-0.1%磷酸为流动相梯度洗脱,HPLC法同时测定12... 目的以10种成分为指标,建立白术厚朴合剂HPLC定量分析方法,联合化学计量学及熵权优劣解距离法(EW-TOPSIS)对其质量进行综合评价。方法以75%甲醇提取液为样品,采用Agilent TC-C18色谱柱,乙腈-0.1%磷酸为流动相梯度洗脱,HPLC法同时测定12批白术厚朴合剂中10个化合物(白术内酯Ⅲ、白术内酯Ⅰ、肉桂醇、肉桂酸、桂皮醛、和厚朴酚、厚朴酚、6-姜辣素、8-姜酚和10-姜酚)含量,运用化学计量学和EW-TOPSIS法对含量数据进行分析。结果经方法学验证,各指标均符合《中华人民共和国药典》要求:10种成分在各自质量浓度范围内线性关系良好,相关系数>0.999;精密度、稳定性、重复性、加样回收率RSD均<2.0%。化学计量学分析显示,前2个主成分代表10个成分92.24%的信息,12批样品聚为3类,桂皮醛、厚朴酚、和厚朴酚、白术内酯Ⅲ、6-姜辣素和白术内酯Ⅰ对白术厚朴合剂的质量影响较大。EW-TOPSIS法结果显示,12批白术厚朴合剂的最优解欧氏贴近度均值为0.2385~0.6662,各批次间质量差异较大。结论建立的多指标成分定量方法操作便捷、结果准确,可用于白术厚朴合剂的质量控制,化学计量学及EW-TOPSIS分析可实现对白术厚朴合剂质量的综合评价,为白术厚朴合剂质量标准提升提供参考。 展开更多
关键词 白术厚朴合剂 高效液相色谱法 化学计量学 多指标成分 熵权优劣解距离法 质量评价
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