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Spatial Distribution Characteristics and Coverage Rate of Commercial Facilities in 15-minute Radius Livelihood Service Circles of Chunshu Street
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作者 HAN Qiqi YANG Kaitai 《Journal of Landscape Research》 2024年第1期17-21,共5页
Building a 15-minute radius livelihood service circle from the needs of residents is a topdown process of optimizing urban layout and promoting high-quality development implemented by the government.In September 2022,... Building a 15-minute radius livelihood service circle from the needs of residents is a topdown process of optimizing urban layout and promoting high-quality development implemented by the government.In September 2022,Xicheng District of Beijing served as a national pilot of the 15-minute radius livelihood service circle.Based on the data of POI,urban walking network and building outline,this paper studies the coverage of commercial service facilities in the 15-minute radius livelihood service circle of Chunshu Street by using kernel density analysis and urban network analysis tools.The research shows that the commercial facilities are concentrated in Zhuangsheng Square and Dazhalan commercial district.There are large gaps in housekeeping and couriers logistics facilities,which need to be further improved. 展开更多
关键词 Chunshu Street 15-minute radius livelihood service circle POI Historic urban areas Community business
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Enhancing Women's Well-being and Self-Confidence through Fragrance Cosmetics:Perceptions within Close and Broader Social Circles
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作者 Yang Fan Guo Miao +1 位作者 Zhou Ziyan Abriat Anne 《China Detergent & Cosmetics》 CAS 2024年第2期69-78,共10页
Mental and physical stress can affect people's self-confidence and happiness.The primary objective of this study is to develop an active fragrance that has been proved to have a positive effect on happiness and se... Mental and physical stress can affect people's self-confidence and happiness.The primary objective of this study is to develop an active fragrance that has been proved to have a positive effect on happiness and self-confidence based on the latest research results of aroma components and fragrance innovation.The active fragrance is applied to the cream formula to study the emotions it brings to the user and extend the research scope of the active emotion to the close and extensive social circle of users to see whether it can perceive it.This study provides a reference cosmetic solution for emotional regulating active fragrance. 展开更多
关键词 FRAGRANCE emotion CREAM social circle
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改进麻雀搜索算法的四旋翼无人机路径规划
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作者 朱易凡 裘旭冬 李硕 《传感器与微系统》 北大核心 2025年第1期141-145,151,共6页
针对麻雀搜索算法(SSA)容易陷入局部最优、求解精度不高和收敛速度较慢的问题,本文提出一种非线性正态差分SSA(NLN-DSSA)。采用改进Circle混沌映射初始化麻雀种群,提升种群多样性,提高算法在迭代开始时的全局搜索能力;引入非线性正态分... 针对麻雀搜索算法(SSA)容易陷入局部最优、求解精度不高和收敛速度较慢的问题,本文提出一种非线性正态差分SSA(NLN-DSSA)。采用改进Circle混沌映射初始化麻雀种群,提升种群多样性,提高算法在迭代开始时的全局搜索能力;引入非线性正态分布系数来控制发现者的搜索步长和收敛速度,平衡全局搜索和局部开发能力;引进差分变异策略增加种群的多样性,帮助算法跳出局部最优。在5个基准测试函数上寻优实验,结果表明:NLN-DSSA具有更好的收敛速度和寻优精度。最后将NLN-DSSA应用到无人机路径规划上,证明改进算法的有效性和实用性。 展开更多
关键词 麻雀搜索算法 Circle混沌映射 非线性正态差分 差分变异 路径规划
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Detecting Circles Using a Two-Stage Approach 被引量:1
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作者 Wen-Yen Wu 《Journal of Electronic Science and Technology》 CAS 2014年第3期318-321,共4页
We propose a two-stage method for detecting circular objects in this paper. In the first stage, curves are divided as linear segments or nonlinear segments. A least square estimator is used to find the estimated cente... We propose a two-stage method for detecting circular objects in this paper. In the first stage, curves are divided as linear segments or nonlinear segments. A least square estimator is used to find the estimated centers and radii of the nonlinear segments in the second stage. The found centers and radii are then evaluated to see if there exist circles in the nonlinear segments. Both of the broken and occluded circular objects are evaluated for the proposed method. From the experimental results, it is seen that the proposed method is efficient. 展开更多
关键词 Circle detection curve segmentation error estimation FITTING
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Finite element analysis of slope stability by expanding the mobilized principal stress Mohr's circles-Development, encoding and validation 被引量:2
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作者 Djillali Amar Bouzid 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第4期1165-1179,共15页
In recent years,finite element analysis is increasingly being proposed in slope stability problems as a competitive method to traditional limit equilibrium methods(LEMs)which are known for their inherent deficiencies.... In recent years,finite element analysis is increasingly being proposed in slope stability problems as a competitive method to traditional limit equilibrium methods(LEMs)which are known for their inherent deficiencies.However,the application of finite element method(FEM)to slope stability as a strength reduction method(SRM)or as finite element limit analysis(FELA)is not always a success for the drawbacks that characterize both methods.To increase the performance of finite element analysis in this problem,a new approach is proposed in this paper.It consists in gradually expanding the mobilized stress Mohr’s circles until the soil failure occurs according to a prescribed non-convergence criterion.The present approach called stress deviator increasing method(SDIM)is considered rigorous for three main reasons.Firstly,it preserves the definition of the factor of safety(FOS)as the ratio of soil shear strength to the mobilized shear stress.Secondly,it maintains the progressive development of shear stress resulting from the increase in the principal stress deviator on the same plane,on which the shear strength takes place.Thirdly,by introducing the concept of equivalent stress loading,the resulting trial stresses are checked against the violation of the actual yield criterion formed with the real strength parameters rather than those reduced by a trial factor.The new numerical procedure was encoded in a Fortran computer code called S^(4)DINA and verified by several examples.Comparisons with other numerical methods such as the SRM,gravity increasing method(GIM)or even FELA by assessing both the FOS and contours of equivalent plastic strains showed promising results. 展开更多
关键词 Slope stability Finite element analysis Strength reduction method(SRM) Stress point-based factor of safety(FOS) Limit equilibrium method(LEM) Stress deviator Mohr’s circle Plastic strain
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GENERALIZED CIRCLES AND THEIR CONFORMAL MAPPING IN A SUBSPACE OF A WEYL SPACE
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作者 Güler Gürpinar Arsan Gülcin Civi Yildirim 《Acta Mathematica Scientia》 SCIE CSCD 2005年第2期331-339,共9页
The authors give the necessary and sufficient conditions for a generalized circle in a Weyl hypersurface to be generalized circle in the enveloping Weyl space. They then obtain the neccessary and sufficient conditions... The authors give the necessary and sufficient conditions for a generalized circle in a Weyl hypersurface to be generalized circle in the enveloping Weyl space. They then obtain the neccessary and sufficient conditions under which a generalized concircular transformation of one Weyl space onto another induces a generalized transformation on its subspaces. Finally, it is shown that any totally geodesic or totally umbilical hypersurface of a generalized concircularly flat Weyl space is also generalized concircularly flat. 展开更多
关键词 Weyl space generalized circle generalized concircular transformation totally umbilical space generalized concircular flat space
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Study on the Constructing Strategies of Rural Life Circles in Chinese Metropolitan Areas
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作者 Dongshu Li Yueping Hu Darong Deng 《Journal of World Architecture》 2020年第2期10-13,共4页
Based on the aims of“issues of agriculture”and“three highs”in the new era,the metropolitan rural areas are targeted under the trend of counterurbanization.It follows the theory of Social Space Building,Maslow'... Based on the aims of“issues of agriculture”and“three highs”in the new era,the metropolitan rural areas are targeted under the trend of counterurbanization.It follows the theory of Social Space Building,Maslow's Theory of Demand,and the theory of Social Governance.It mainly explores rural constructing strategies on development and the life with clear governance integration,range,hierarchy and main function as well as completing the issues such as ecology,culture,industry,living environment and livelihood facilities. 展开更多
关键词 VILLAGERS CITIZEN LIFE circles
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Maritime Arbitration Creates a Legal Environment For Shipping Circles
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《China's Foreign Trade》 2002年第10期30-31,共2页
关键词 CMAC Maritime Arbitration Creates a Legal Environment For Shipping circles
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基于MDS和改进SSA-SVM的高速铁路道岔故障诊断方法研究 被引量:1
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作者 王彦快 米根锁 +2 位作者 孔得盛 杨建刚 张玉 《铁道学报》 EI CAS CSCD 北大核心 2024年第1期81-90,共10页
针对高速铁路道岔设备故障频繁,现场维修工作量大等问题,提出基于多维尺度缩放法(MDS)和改进麻雀搜索算法(SSA)优化支持向量机(SVM)的高速铁路道岔故障诊断模型。首先以ZDJ9道岔转换功率曲线为研究对象,总结现场典型道岔故障类型及故障... 针对高速铁路道岔设备故障频繁,现场维修工作量大等问题,提出基于多维尺度缩放法(MDS)和改进麻雀搜索算法(SSA)优化支持向量机(SVM)的高速铁路道岔故障诊断模型。首先以ZDJ9道岔转换功率曲线为研究对象,总结现场典型道岔故障类型及故障原因,分别提取道岔功率曲线的时域、频域特征指标以及小波包能量熵,组成特征指标向量;其次采用MDS方法进行多维特征指标的降维优化,建立道岔故障特征指标样本数据库;最后利用改进Circle混沌映射初始化种群,并通过自适应t分布增强麻雀种群的多样性,再以改进SSA算法优化SVM模型中的惩罚因子和核函数方差2个关键参数,构建改进SSA-SVM的道岔故障诊断模型。故障诊断结果表明,本模型的故障诊断正确率高达96.25%,诊断效果优于其他方法,可以为道岔设备的故障维修提供理论依据。 展开更多
关键词 高速铁路道岔 故障诊断 改进麻雀搜索算法-支持向量机 Circle混沌映射 自适应t分布 小波包能量熵 多维尺度缩放法
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Strengthening Standardized Construction of Band Card,Integrating with International Financial Circles
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作者 Song Lei 《China Standardization》 2005年第6期24-27,共4页
Following the accession to the WTO of China,bank card industry faces new competition pressure and challenges. At present, the most outstanding problem we face is, how to narrow the gap of development between the inter... Following the accession to the WTO of China,bank card industry faces new competition pressure and challenges. At present, the most outstanding problem we face is, how to narrow the gap of development between the international bank card industry and that of China and keep up with fast-developing paces of international bank card as soon as possible. Objectively speaking, bank card industry of our country is still at the initial stage. 展开更多
关键词 CARD Strengthening Standardized Construction of Bank Card Integrating with International Financial circles Bank Innovation EMV
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Analysis of the Higher Education Research in the Chengdu-Chongqing Region:A Comparative Perspective Based on Three Major Economic Circles in China
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作者 Dai Rui Luo Hong Xie Xiaoli 《Contemporary Social Sciences》 2023年第1期102-115,共14页
Drawing on literature regarding higher education research retrieved from the CNKI database from 1997 to 2021,this paper used CiteSpace to analyze the current status of higher education research in the Chengdu-Chongqin... Drawing on literature regarding higher education research retrieved from the CNKI database from 1997 to 2021,this paper used CiteSpace to analyze the current status of higher education research in the Chengdu-Chongqing economic circle.By comparing it with that in the Beijing-Tianjin-Hebei region,the Guangdong-Hong Kong-Macao Greater Bay Area,and the Yangtze River Delta,this paper concluded that the level of higher education research within a region is in line with the level of the region’s economic and social development.As higher education research in the Chengdu-Chongqing economic circle draws more and more attention,its research areas and topics are becoming increasingly diversified.However,by comparison,the research in this region features a late start and lower participation of researchers and research institutions,resulting in insufficient research in both quantity and quality.Therefore,it is essential to encourage more experts and scholars to participate in higher education research in the Chengdu-Chongqing economic circle.Efforts should also be made to strengthen academic exchanges and cooperation between scholars in Chengdu and Chongqing and establish a long-term cooperation mechanism for higher education research between the two cities.Improved higher education research will definitely facilitate the construction of first-class universities,thus providing human capital and intellectual support for the construction of the Chengdu-Chongqing economic circle. 展开更多
关键词 higher education research Chengdu-Chongqing economic circle Beijing-Tianjin-Hebei region Guangdong-Hong Kong-Macao Greater Bay Area Yangtze River Delta
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Chinese Composers Make Their Mark in U.S. Music Circles
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《China & The World Cultural Exchange》 1995年第3期10-12,共3页
关键词 Chinese Composers Make Their Mark in U.S Music circles
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改进麻雀搜索算法的入侵检测特征选择 被引量:1
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作者 刘涛 蒙学强 《计算机工程与设计》 北大核心 2024年第4期989-996,共8页
针对网络入侵检测所处理数据存在特征维数高、检测效率低、准确率不高的问题,提出一种改进麻雀搜索算法的特征选择方法,旨在减少特征冗余的同时提高分类准确率。利用改进Circle映射初始化种群;结合秃鹰搜索算法中的螺旋搜索方式更新发... 针对网络入侵检测所处理数据存在特征维数高、检测效率低、准确率不高的问题,提出一种改进麻雀搜索算法的特征选择方法,旨在减少特征冗余的同时提高分类准确率。利用改进Circle映射初始化种群;结合秃鹰搜索算法中的螺旋搜索方式更新发现者位置;采用单纯形法和小孔成像法优化适应度较差和最优麻雀的位置,提升算法的寻优能力。将该算法与其它算法在6个经典基准函数上进行对比测试,其在收敛速度、精度等方面均有提升。使用数据集CIC-IDS2017进行特征选择实验,平均保留了7.6个特征,准确率达到了99.5%,结果表明,该算法可以在保证准确率的同时有效降低特征维度。 展开更多
关键词 麻雀搜索算法 Circle映射 螺旋搜索 单纯形法 小孔成像 入侵检测 特征选择
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基于改进INFO-Bi-LSTM模型的SO_(2)排放质量浓度预测 被引量:1
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作者 王琦 柴宇唤 +2 位作者 王鹏程 刘百川 刘祥 《动力工程学报》 CAS CSCD 北大核心 2024年第4期641-649,共9页
针对火电机组SO_(2)排放质量浓度的影响因素众多,难以准确预测的问题,提出一种改进向量加权平均(weighted mean of vectors,INFO)算法与双向长短期记忆(bi-directional long short term memory,Bi-LSTM)神经网络相结合的预测模型(改进IN... 针对火电机组SO_(2)排放质量浓度的影响因素众多,难以准确预测的问题,提出一种改进向量加权平均(weighted mean of vectors,INFO)算法与双向长短期记忆(bi-directional long short term memory,Bi-LSTM)神经网络相结合的预测模型(改进INFO-Bi-LSTM模型)。采用Circle混沌映射和反向学习产生高质量初始化种群,引入自适应t分布提升INFO算法跳出局部最优解和全局搜索的能力。选取改进INFO-Bi-LSTM模型和多种预测模型对炉内外联合脱硫过程中4种典型工况下的SO_(2)排放质量浓度进行预测,将预测结果进行验证对比。结果表明:改进INFO算法的寻优能力得到提升,并且改进INFO-Bi-LSTM模型精度更高,更加适用于SO_(2)排放质量浓度的预测,可为变工况下的脱硫控制提供控制理论支撑。 展开更多
关键词 炉内外联合脱硫 烟气SO_(2)质量浓度 INFO算法 Bi-LSTM神经网络 Circle混沌映射 自适应t分布
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Word Problems about Circles
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作者 焦瑞 《疯狂英语(理论版)》 2019年第1期38-42,共5页
In primary school maths, CIRCLE is one of the most important units. Some of the students would think it would be okay to be able to understand the relationship between the diameter or the radius and the circumference ... In primary school maths, CIRCLE is one of the most important units. Some of the students would think it would be okay to be able to understand the relationship between the diameter or the radius and the circumference or the area of a circle.Here is a word problem:Choose the correct option A, B or C.Inthesquare,thereisaquartercircleandasmallcircle. 展开更多
关键词 In WORD PROBLEMS circles
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The Application of Quality Control Circles to Reduce the Cost of Non-priced Consumables in Department of Oncology
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作者 Xiaofang Zhang Jinglan Luo +5 位作者 Rui Dai Lu Wang Jieli Wei Yingying Liang Qiugui Huang Yuyao Liu 《Journal of Clinical and Nursing Research》 2021年第3期140-143,共4页
Objective:To investigate the effectiveness of using quality control circle(QCC)techniques to reduce the cost of non-priced consumables in medical oncology.Methods:Analytic statistics were compiled on the performance a... Objective:To investigate the effectiveness of using quality control circle(QCC)techniques to reduce the cost of non-priced consumables in medical oncology.Methods:Analytic statistics were compiled on the performance appraisal form.Aiming at the key points of improvement with respect to the excess cost of non-valuable consumables,the reasons were analyzed,and corresponding measures were formulated to compare the cost before and after the improvement.Results:After the QCC activity,the cost of non-priced consumables decreased from RMB 6.57/bed day to RMB 3.96/bed day.Conclusion:QCC has effectively reduced the cost of non-priced consumables in the oncology department,and it is worthy of promotion. 展开更多
关键词 Quality control circles Reduction non-priced consumables Cost
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Use of Quality Control Circles-A Fad or Need
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作者 AMIR Manzur Wain SHAHID Ikramullah Butt 《Computer Aided Drafting,Design and Manufacturing》 2006年第1期44-49,共6页
Different techniques including Quality Control Circles, Business Process Reengineering and Statistical Process Control (SPC), Total Quality Management have been in use to reduce waste in the industry. Waste is consi... Different techniques including Quality Control Circles, Business Process Reengineering and Statistical Process Control (SPC), Total Quality Management have been in use to reduce waste in the industry. Waste is considered as necessary evil and there are many types of waste in the industry. There are many ways and means to reduce waste but the less costly is to use Quality Control Circles technique effectively and efficiently. In quality control circles human resources that consist of small groups of employees are selected, who voluntarily meet at regular intervals to identify, analyze and solve quality and other problems in their work areas. In the Quality Control Circles different techniques of the quality improvement and total quality management are utilized which could be numeric or nonnumeric such as statistical quality control techniques and fish bone diagram or brain storming respectively. This article discusses that how reduction of waste in Pakistan industry is possible by using Quality Control Circles implementation. 展开更多
关键词 Quality Control circles (QCCs) FAD waste reduction continuous improvement processes
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A Small Universe of Circles and Squares--Hakka Folk Buildings in China
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作者 Zhao juan&Shao Quanxuan 《大美术》 2007年第4期131-138,共8页
At the common boundary of Min, Yue and Ga lies a world of mountains, brooks, forests and bamboos that hide some of China's best kept architectural secrets:the legendary folk buildings of the Hakka. Inspiring awe i... At the common boundary of Min, Yue and Ga lies a world of mountains, brooks, forests and bamboos that hide some of China's best kept architectural secrets:the legendary folk buildings of the Hakka. Inspiring awe in all who have stumbled upon them, these fortresses are home 展开更多
关键词 A Small Universe of circles and Squares Hakka Folk Buildings in China
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A Grand Event for Cultural Circles──Publication Begins of the 40-volume King Gesar
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《China's Tibet》 2001年第2期27-27,共1页
关键词 A Grand Event for Cultural circles Publication Begins of the 40-volume King Gesar
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融合T-分布小波变异的混沌鲸鱼优化算法
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作者 毛清华 赵冰 王迎港 《小型微型计算机系统》 CSCD 北大核心 2024年第10期2362-2369,共8页
针对鲸鱼优化算法难以跳出局部最优导致收敛精度不足的问题,提出一种融合了T-分布小波变异和多项式差分学习策略的鲸鱼优化算法.该算法首先引入Circle混沌扩大搜索范围,提高收敛速度;然后采用T-分布小波变异策略平衡全局和局部搜索能力... 针对鲸鱼优化算法难以跳出局部最优导致收敛精度不足的问题,提出一种融合了T-分布小波变异和多项式差分学习策略的鲸鱼优化算法.该算法首先引入Circle混沌扩大搜索范围,提高收敛速度;然后采用T-分布小波变异策略平衡全局和局部搜索能力;最后采用多项式差分学习策略改进算法的优化精度.对3种改进策略作单一引入的仿真对比分析,并将改进的鲸鱼优化算法在12个可变维度的基准测试函数上进行仿真,对本文改进的鲸鱼优化算法与其他改进策略的鲸鱼优化算法以及其他几种智能算法进行比较.结果表明,基于T-分布小波变异和多项式差分学习策略的改进鲸鱼优化算法具有较好的稳定性,收敛速度和精度更好. 展开更多
关键词 鲸鱼优化算法 Circle混沌映射 T-分布小波变异 多项式差分学习
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