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Prenatal radiographic evaluation of congenital transverse limb deficiencies:A scoping review
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作者 Neeraj Vij Luis F Goncalves +2 位作者 Aaron Llanes Sean Youn Mohan V Belthur 《World Journal of Orthopedics》 2023年第3期155-165,共11页
BACKGROUND Congenital transverse deficiencies are horizontal deficiencies of the long bones that occur with a reported incidence as high 0.38%.They can occur alone or represent a manifestation of a various clinical sy... BACKGROUND Congenital transverse deficiencies are horizontal deficiencies of the long bones that occur with a reported incidence as high 0.38%.They can occur alone or represent a manifestation of a various clinical syndromes.Diagnosis has tradi-tionally comprised of conventional radiography and prenatal imaging studies.There has been much advancement regarding prenatal imaging modalities to allow for early diagnosis and appropriate treatment.AIM To summarize the current state of knowledge on congenital transverse limb deficiencies and to provide an update regarding the radiographic evaluation of congenital transverse limb deficiencies.METHODS This IRB-exempt scoping review followed the PRISMA-ScR checklist for scoping reviews strictly.Five search engines were searched for a total of 265 publications.Four authors reviewed these during the screening process.Of these,51 studies were included in our article.Prenatal magnetic resonance imaging(MRI),3D Ultrasound,and multidetector Computed tomography(CT)exist are emerging modalities that have the potential to improve diagnosis.RESULTS Use of the appropriate classification system,three-dimensional ultrasonography with a maximum intensity projection,and appropriate use of prenatal MRI and prenatal CT can improve diagnosis and inter-provider communication.CONCLUSION Further scholarly efforts are required to develop improve standardized guidelines regarding the pre-natal radiographic evaluation of congenital limb deficiencies. 展开更多
关键词 Terminal deficiencies Roentgenographic evaluation Pediatric skeletal deficiencies Early diagnosis Patient-centered care Prenatal imaging©The Author(s)2023.Published by Baishideng Publishing Group Inc.All rights reserved.
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Exploring Taiwan’s China Landscape Painting Aesthetic Preferences Through Evaluation Grid Method and the Continuous Fuzzy Kano Model
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作者 Chin-Chin Kuo Jiann-Sheng Jiang Min-Min Lin 《Journal of Contemporary Educational Research》 2023年第12期268-276,共9页
The primary objective of this study is to apply the Evaluation Grid Method(EGM)and the continuous fuzzy Kano quality model to explore the cognitive preferences of Taiwan China residents regarding the beauty of Taiwan... The primary objective of this study is to apply the Evaluation Grid Method(EGM)and the continuous fuzzy Kano quality model to explore the cognitive preferences of Taiwan China residents regarding the beauty of Taiwan’s China landscape paintings.The aim is to contribute to the development of social and cultural art and promote the widespread appeal of art products.Through a literature review,consultations with aesthetic experts,and the application of Miryoku Engineering’s EGM,this paper consolidates the factors that contribute to the attractiveness of painting art products among Taiwan China residents,taking into account various aesthetic qualities.Simultaneously,the paper introduces the use of the triangular fuzzy golden ratio scale semantics,specifically the equal-ratio aesthetic scale semantics,as a replacement for the traditional subjective consciousness model.Departing from the traditional discrete Kano model that employs the mode as the standard for evaluating quality,this study applies triangular fuzzy numbers to the continuous Kano quality model to analyze the diverse preferences and evaluation standards of the public.The hope is that this research methodology will not only deepen Taiwan China residents’understanding and aesthetic literacy of painting art but also serve as a reference for the popularization of art products. 展开更多
关键词 Aesthetic literacy Taiwan’s landscape painting Miryoku engineering evaluation grid method(EGM) Fuzzy Kano model Golden ratio scale semantics
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Model and method of permeability evaluation based on mud invasion effects 被引量:3
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作者 周峰 胡祥云 +2 位作者 孟庆鑫 胡旭东 刘志远 《Applied Geophysics》 SCIE CSCD 2015年第4期482-492,626,共12页
The evaluation of permeability in reservoir assessment is a complex problem. Thus, it is difficult to perform direct evaluation permeability with conventional well-logging methods. Considering that reservoir permeabil... The evaluation of permeability in reservoir assessment is a complex problem. Thus, it is difficult to perform direct evaluation permeability with conventional well-logging methods. Considering that reservoir permeability significantly affects mud invasion during drilling, we derive a mathematical model to assess the reservoir permeability based on mud invasion. A numerical model is first used to simulate the process of mud invasion and mud cake growth. Then, based on Darcy's law, an approximation is derived to associate the depth of mud invasion with reservoir permeability. A mathematical model is constructed to evaluate the reservoir permeability as a function of the mud invasion depth in time-lapse logging. Sensitivity analyses of the reservoir porosity, permeability, and water saturation are performed, and the results suggest that the proposed model and method are well suited for oil layers or oil-water layers of low porosity and low permeability. Numerical simulations using field logging and coring data suggest that the evaluated and assumed permeability data agree, validating the proposed model and method. 展开更多
关键词 mud invasion mud cake permeability evaluation Darcy's law
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Investigation on Phytoplankton and Water Quality Evaluation in Landscape Water of Campus in Nanjing Xianlin University Town 被引量:4
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作者 王琳 李敬伟 +5 位作者 夏娴 赵璐 孙晨霞 田园园 汪育文 许小军 《Journal of Landscape Research》 2010年第11期80-83,共4页
The major phytoplankton was investigated and analyzed in landscape water of six campuses in Nanjing Xianlin University Town,and water quality was evaluated by single factor assessment method and comprehensive weighted... The major phytoplankton was investigated and analyzed in landscape water of six campuses in Nanjing Xianlin University Town,and water quality was evaluated by single factor assessment method and comprehensive weighted evaluation method.The result showed that the major phytoplankton groups were Cyanophyta,Chlorophyta and Bacillariophyta.Besides,each evaluation indicator showed that waterbodies in four campuses were eutrophicated and result of single factor evaluation showed water quality all belonged to poor category V.The result of comprehensive weighted assessment showed that waters in Nanjing Normal University and Nanjing University of Posts and Telecommunications were seriously polluted,cyanobacterial bloom appearing.Waters in Nanjing University of Chinese Medicine and Nanjing Forest Police College hadn't been eutrophicated. 展开更多
关键词 Campuss LANDsCAPE WATER PHYTOPLANKTON WATER QUALITY evaluation
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基于S-CAD方法的宅基地“三权分置”改革试点政策评估——以新疆试点市县为例
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作者 张晔 李婕 《江西农业学报》 CAS 2024年第7期117-126,共10页
采用S-CAD政策评估方法对新疆宅基地“三权分置”政策试点地区伊宁市和奇台县的政策执行效果进行评价,研究发现伊宁市和奇台县两试点政策整体逻辑一致性较好、政策要素之间具备充分性与必要性,利益相关者支持程度较高,有效实现了宅基地... 采用S-CAD政策评估方法对新疆宅基地“三权分置”政策试点地区伊宁市和奇台县的政策执行效果进行评价,研究发现伊宁市和奇台县两试点政策整体逻辑一致性较好、政策要素之间具备充分性与必要性,利益相关者支持程度较高,有效实现了宅基地“三权分置”改革的政策目标,但仍存在政策手段与政策目标充要性不足,预期政策效果与实际政策效果有一定偏差等问题。针对此,提出宅基地“三权分置”改革政策应适应城乡融合发展趋势,加强农户利益保障机制建设;坚持因地制宜,创新农村宅基地“三权分置”改革思路;兼顾多方利益与公平,提升综合价值效应的建议。 展开更多
关键词 宅基地 三权分置 s-CAD方法 政策评估
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基于混淆S盒的高维量子同态加密机制
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作者 宋秀丽 周建兵 +3 位作者 廖金伟 邓红耀 刘羽 吴涛 《密码学报(中英文)》 CSCD 北大核心 2024年第5期1003-1017,共15页
在量子同态加密机制中,对密文量子态执行同态评估计算并解密得到的结果与对明文量子态直接评估计算所得的结果相同.现有的量子同态加密机制不仅评估算子的逻辑门种类有限,而且使用单点或多点混淆导致计算开销较大.鉴于此,本文使用量子... 在量子同态加密机制中,对密文量子态执行同态评估计算并解密得到的结果与对明文量子态直接评估计算所得的结果相同.现有的量子同态加密机制不仅评估算子的逻辑门种类有限,而且使用单点或多点混淆导致计算开销较大.鉴于此,本文使用量子随机游走构建了一个混淆S盒并将其应用到高维量子同态加密机制的设计之中.客户端使用高维的Pauli算子对明文量子态加密之后,将密文量子态发送至服务器;服务器从评估算子集合中选取客户端需要的评估算子,配合评估参数对密文量子态执行评估操作,并将评估结果发送至解密方执行解密运算.为了避免服务器在执行评估操作时泄露解密密钥,客户端通过设计的混淆S盒来完成对解密密钥的混淆并将结果传输给解密方.解密方执行逆混淆S盒还原出解密密钥,并使用该密钥执行解密操作得到委托计算结果.对比同类型的相似机制,该机制增加了评估算子的种类,降低了量子混淆S盒的开销;通过仿真实验结果证明了提出机制的正确性,并从信息理论层面证明了该机制的安全性. 展开更多
关键词 量子同态加密 混淆s 高维量子逻辑门 评估算子集合
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Urban Construction Land Suitability Evaluation Based on Improved Multi-criteria Evaluation Based on GIS(MCE-GIS): Case of New Hefei City,China 被引量:23
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作者 ZHANG Xiaorui FANG Chuanglin +1 位作者 WANG Zhenbo MA Haitao 《Chinese Geographical Science》 SCIE CSCD 2013年第6期740-753,共14页
Urban construction land suitability evaluation (UCLSE) is a complex system engineering and the basis for rational use of the limited urban land resources in China. It has an important practical value on urban constr... Urban construction land suitability evaluation (UCLSE) is a complex system engineering and the basis for rational use of the limited urban land resources in China. It has an important practical value on urban construction land use planning and management from the angle of methodology. As a widely used technique, traditional multi-criteria evaluation based on GIS (MCE-GIS), is not suitable for UCLSE. This study develops an improved MCE-GIS method which could be more suitable for UCLSE based on urban complex ecological system theory and the summary of the shortcomings of traditional MCE-GIS. The improvements include three aspects: a composite evaluation index system rather than natural indexes alone, an index weight calculated by using fuzzy Analytic Hierarchy Process (AHP) method rather than the common AHP method, and the integrated overlay rule, which includes selecting the minimum value, weighted linear combination (WLC) and simple summation. The main advantage of this improved technique is that it can make UCLSE more comprehensive, more operational and more reasonable. It can provide a scientific basis for decision making in the planning and management of urban construction land use. The improved MCE-GIS system has been adopted in the New Hefei City, Anhui Province, China. Based on the results of UCLSE in New Hefei, three functional areas including construction-appropriate areas, construction-restricted areas and construction-forbidden areas could be worked out, in which 36.90% of the total study area could be developed as urban construction land and the remaining 63.10% should be protected as reserves land or as ecological land. Furthermore, the results can orovide scientific decision suooort for spatial planning and eco-environment nrotection in New Hefei. 展开更多
关键词 urban construction land suitability evaluation (UCLsE) multi-criteria evaluation based on GIs (MCE-G1s New Hefei
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Reliability Evaluation of Machine Center Components Based on Cascading Failure Analysis 被引量:3
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作者 Ying-Zhi Zhang Jin-Tong Liu +2 位作者 Gui-Xiang Shen Zhe Long Shu-Guang Sun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第4期933-942,共10页
In order to rectify the problems that the com- ponent reliability model exhibits deviation, and the evalu- ation result is low due to the overlook of failure propagation in traditional reliability evaluation of machin... In order to rectify the problems that the com- ponent reliability model exhibits deviation, and the evalu- ation result is low due to the overlook of failure propagation in traditional reliability evaluation of machine center components, a new reliability evaluation method based on cascading failure analysis and the failure influ- enced degree assessment is proposed. A direct graph model of cascading failure among components is established according to cascading failure mechanism analysis and graph theory. The failure influenced degrees of the system components are assessed by the adjacency matrix and its transposition, combined with the Pagerank algorithm. Based on the comprehensive failure probability function and total probability formula, the inherent failure proba- bility function is determined to realize the reliability evaluation of the system components. Finally, the method is applied to a machine center, it shows the following: 1) The reliability evaluation values of the proposed method are at least 2.5% higher than those of the traditional method; 2) The difference between the comprehensive and inherent reliability of the system component presents a positive correlation with the failure influenced degree ofthe system component, which provides a theoretical basis for reliability allocation of machine center system. 展开更多
关键词 s Cascading failure Machine centercomponents Reliability evaluation Pagerank algorithmInfluenced degree
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Performance Evaluation of Public Bus Transportation by Using DEA Models and Shannon’s Entropy:An Example From a Company in a Large City of China 被引量:7
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作者 Zicheng Liu Naiqi Wu +1 位作者 Yan Qiao Zhiwu Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第4期779-795,共17页
The purpose of this paper is to assess the operational efficiency of a public bus transportation via a case study from a company in a large city of China by using data envelopment analysis(DEA)model and Shannon’s ent... The purpose of this paper is to assess the operational efficiency of a public bus transportation via a case study from a company in a large city of China by using data envelopment analysis(DEA)model and Shannon’s entropy.This company operates 37 main routes on the backbone roads.Thus,it plays a significant role in public transportation in the city.According to bus industry norms,an efficiency evaluation index system is constructed from the perspective of both company operations and passenger demands.For passenger satisfaction,passenger waiting time and passenger-crowding degree are considered,and they are undesirable indicators.To describe such indicators,a superefficient DEA model is constructed.With this model,by using actual data,efficiency is evaluated for each bus route.Results show that the DEA model with Shannon’s entropy being combined achieves more reasonable results.Also,sensitivity analysis is presented.Therefore,the results are meaningful for the company to improve its operations and management. 展开更多
关键词 Performance evaluation public transportation system shannon’s entropy super-efficiency data envelopment analysis undesirable outputs
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Positron emission tomography/computerized tomography in the evaluation of primary non-Hodgkin's lymphoma of prostate 被引量:4
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作者 Bo Pan Jian-Kui Han +1 位作者 Shi-Cun Wang Ao Xu 《World Journal of Gastroenterology》 SCIE CAS 2013年第39期6699-6702,共4页
Primary malignant lymphoma of the prostate is exceedingly rare.Here we report a case of a 65-year-old man who presented with increased urinary frequency,urinary urgency,and urinary incontinence for two years.Benign pr... Primary malignant lymphoma of the prostate is exceedingly rare.Here we report a case of a 65-year-old man who presented with increased urinary frequency,urinary urgency,and urinary incontinence for two years.Benign prostatic hypertrophy was suspected at primary impression.Ultrasound revealed a hypoechoic lesion of the prostate.The total serum prostate-specific antigen was within normal range.Positron emission tomography/computerized tomography(PET/CT)showed a hypermetabolic prostatic lesion.Prostate biopsy was consistent with a non-germinal center diffuse large B cell lymphoma.There was complete remission of the prostatic lesion following six cycles of chemotherapy as shown on the second PET/CT imaging.18F-fluoro-deoxy glucose PET/CT is not only a complement to conventional imaging,but also plays a significant role in the diagnosis and evaluation of treatment response of prostatic lymphoma. 展开更多
关键词 Fluoro-Deoxy-Glucose Positron emission tomography/computerized tomography Non-Hodgkin’s LYMPHOMA PROsTATIC LYMPHOMA evaluation
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Fatigue life evaluation on key components of high-speed railway catenary system 被引量:6
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作者 QI Guang-feng XIAO Xiao-hui +1 位作者 ZHAO Hui CHEN Jian-fang 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第8期1958-1965,共8页
The fatigue load spectrum and operation life evaluation of key components in the catenary system under the high speed train running condition were investigated.Firstly,based on the catenary model and pantograph model,... The fatigue load spectrum and operation life evaluation of key components in the catenary system under the high speed train running condition were investigated.Firstly,based on the catenary model and pantograph model,the couple dynamic equations of pantograph–catenary were built with the Lagrange’s method;then the dynamic contact force was obtained by the Newmark method at the train speeds of 250,280 and 300 km/h,respectively.Secondly,the finite element model(FEM)of one anchor section’s catenary was built to analyze its transient response under the contact force as train running;then the loading time history of messenger wire base,steady arm,registration tube,oblique cantilever,and straight cantilever were extracted.Finally,the key components’fatigue spectrum was carried out by the rain-flow counting method,and operation life was estimated in consideration of such coefficients,such as stress concentration,shape and dimension,surface treatment.The results show that the fatigue life of the catenary system reduces with the increasing of train speed;specifically,the evaluated fatigue life of the steady arm is shorter than other components. 展开更多
关键词 fatigue spectrum fatigue life evaluation pantograph–catenary’s contact force high-speed railway
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Research on China's Aquaculture Efficiency Evaluation and Influencing Factors with Undesirable Outputs 被引量:2
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作者 JI Jianyue WANG Pingping 《Journal of Ocean University of China》 SCIE CAS 2015年第3期569-574,共6页
Taking the aquaculture area, the number of farming boats and that of aquaculturist as input variables, the aquaculture production as desirable output variable and polluted economic loss as undesirable output variable,... Taking the aquaculture area, the number of farming boats and that of aquaculturist as input variables, the aquaculture production as desirable output variable and polluted economic loss as undesirable output variable, this paper conducts SBM model to evaluate the aquaculture efficiency based on the data of 16 aquaculture-developed provinces in China from 2004 to 2011. The results show the efficiency in China has not changed much in recent years with the efficiency values mainly between 0.39 and 0.53, and the efficiency of marine-aquaculture-dominated provinces is generally higher than that of freshwater-aquaculture-dominated ones. To analyze the difference under the efficiency, the panel Tobit model is used with education level factor, training factor, technology extension factor, technical level factor, scale factor and species factor as the efficiency influencing factors. The results show that technology extension factor and technical level factor have significant positive influence. 展开更多
关键词 China's aquaculture industry efficiency evaluation influencing factors sBM model panel Tobit model
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基于S-CAD法的县域新型城镇化发展规划方案评估研究——以陕西省佳县为例
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作者 付晓萌 张沛 +1 位作者 杨保琨 王娜 《西部人居环境学刊》 CSCD 北大核心 2024年第1期115-121,共7页
规划方案作为相关利益主体价值观的直接体现,应当在规划评估中予以重视。基于城乡规划的公共政策属性,采用S-CAD政策评估方法,以陕西省佳县的《新型城镇化与城乡统筹规划》文本为例,选取规划编制与实施主体——政府作为主导视角,对规划... 规划方案作为相关利益主体价值观的直接体现,应当在规划评估中予以重视。基于城乡规划的公共政策属性,采用S-CAD政策评估方法,以陕西省佳县的《新型城镇化与城乡统筹规划》文本为例,选取规划编制与实施主体——政府作为主导视角,对规划文本的内容进行解构,在此基础上进行规划立场、目标、手段与预期结果的一致性、充要性与依赖性分析。研究发现:一、该规划文本自身的逻辑性较强,各个环节存在基本的对应关系;二、规划文本当中对于产业发展以及由此带来的人口问题、基础设施与公共服务设施问题的解决方案描述较多,对于生态环境保护、交通环境改善以及人口流动的实质性解决方案相对较少,逻辑上存在一定的漏洞,需进一步完善逻辑链条。基于此,提出建立城乡规划全过程评估体系及重视多元利益主体协调关系的建议,以期为相关规划的编制与评估工作提供参考。 展开更多
关键词 s-CAD政策评估方法 县域城镇化 新型城镇化 城乡统筹 文本评估
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ASD与非ASD语言发育迟缓儿童的语言行为能力差异分析
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作者 陈玉美 胡丽娜 牟志伟 《广东医学》 CAS 2024年第6期661-665,共5页
目的通过比较孤独症谱系障碍(autism spectrum disorder,ASD)与非ASD语言发育迟缓儿童的各项语言行为能力,分析两者的特征差异。方法回顾收集2020年1月至2022年12月就诊的确诊为ASD(98例)和非ASD(122例)语言发育迟缓儿童的年龄、性别、... 目的通过比较孤独症谱系障碍(autism spectrum disorder,ASD)与非ASD语言发育迟缓儿童的各项语言行为能力,分析两者的特征差异。方法回顾收集2020年1月至2022年12月就诊的确诊为ASD(98例)和非ASD(122例)语言发育迟缓儿童的年龄、性别、ABC量表和S-S量表得分资料,对两组儿童的结果先进行单因素分析,对单因素分析有统计学差异的项目进行多因素二元logistic回归分析。结果经单因素分析,两组儿童年龄无统计学差异,其他项目包括性别,S-S交流态度能力、S-S操作性课题能力、S-S语言理解能力、S-S语言表达能力和ABC总分均有统计学差异(均P<0.05)。采用输入法把两组有差异的性别、S-S交流态度能力、S-S操作性课题能力、S-S语言理解能力、S-S语言表达能力和ABC总分共6个项目进行多因素二元logistic回归分析,结果表明S-S交流态度能力和ABC总分两个项目是区分两组儿童的独立影响因素(均P<0.05),S-S交流态度不良和ABC总分高均是危险因素。结论S-S交流态度能力和ABC总分是区分ASD和非ASD语言发育迟缓儿童的独立影响因素,临床上对于S-S交流态度不良及ABC总分高的语言发育迟缓儿童要高度警惕是否ASD儿童。 展开更多
关键词 孤独症谱系障碍 语言发育迟缓 s-s评估法 ABC量表 LOGIsTIC回归
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融合专利SAO特征的早期专利价值评估方法
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作者 周小琴 蔡鸿宇 +1 位作者 石进 卢明欣 《情报杂志》 CSSCI 北大核心 2024年第10期176-186,共11页
[研究目的]在知识产权强国战略背景下,存在着专利数量与质量不匹配、技术转化率较低的困境,评估早期专利价值对高价值专利培育工程和专利技术转化具有重要意义。[研究方法]提出一种融合专利SAO网络特征和文本特征的早期专利价值评估方... [研究目的]在知识产权强国战略背景下,存在着专利数量与质量不匹配、技术转化率较低的困境,评估早期专利价值对高价值专利培育工程和专利技术转化具有重要意义。[研究方法]提出一种融合专利SAO网络特征和文本特征的早期专利价值评估方法。首先,从专利摘要和标题中抽取主体-行为-客体(SAO)结构。其次,用社会网络分析法挖掘专利SAO网络的核心组件,得到专利SAO网络中心性特征。然后,将SAO结构序列文本输入Doc2Vec模型,得到专利SAO文本特征。最后,融合专利基础特征和SAO特征,构建基于AutoGluon自动机器学习框架的早期专利价值评估模型。[研究结论]以人工智能产业专利为例进行实证研究,实验结果表明引入专利SAO特征后,模型的准确率、召回率和F1值相比基准模型均提高了2%~5%,证明了专利SAO特征在识别早期高价值专利中的有效性。 展开更多
关键词 专利价值 早期专利价值评估 高价值专利 专利文本 人工智能 专利sAO网络 自动机器学习 社会网络分析
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Weapons system portfolio selection based on the contribution rate evaluation of system of systems 被引量:11
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作者 DOU Yajie ZHOU Zhexuan +1 位作者 ZHAO Danling WEI Yong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第5期905-919,共15页
The weapons system portfolio selection problem arises at the equipment demonstration stage and deals with the military application requirements.Further,the contribution rate of the system is one of the important indic... The weapons system portfolio selection problem arises at the equipment demonstration stage and deals with the military application requirements.Further,the contribution rate of the system is one of the important indicators to evaluate the role of a system,which can facilitate the weapons system portfolio selection.Therefore,combining the system contribution rate with system portfolio selection is the focus of this study.It also focuses on calculating the contribution rates of multiple equipment systems with various types of capabilities.The contribution rate is measured by establishing a hierarchical multi-criteria value model from three dimensions.Based on the value model,the feasible portfolios are developed under certain cost constraints and the optimal weapons system portfolios are obtained by using the classification optimization selection strategy.Finally,an illustrative example is presented to verify the feasibility of the proposed model. 展开更多
关键词 WEAPON sYsTEM sYsTEM of systems (sos) portfolioselection CONTRIBUTION rate evaluation DECIsION analysis
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复合材料层压板S-N曲线模型的综述与评估
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作者 冯炜森 杨成鹏 贾斐 《材料导报》 EI CAS CSCD 北大核心 2024年第22期278-287,共10页
S-N模型是分析预测材料及其结构疲劳寿命的重要基础。本文对复合材料层压板的S-N曲线模型进行了全面综述,并将其归纳为基于数据拟合思想的经验模型和考虑损伤机理的半经验模型。研究发现,应力比是S-N模型需要考虑的关键载荷参数,而包含... S-N模型是分析预测材料及其结构疲劳寿命的重要基础。本文对复合材料层压板的S-N曲线模型进行了全面综述,并将其归纳为基于数据拟合思想的经验模型和考虑损伤机理的半经验模型。研究发现,应力比是S-N模型需要考虑的关键载荷参数,而包含应力比的半经验模型较少、经验模型更为匮乏。拟定了模型评估五个基本标准,选取了两种材料体系、不同铺层结构层合板在不同应力比条件下的八组疲劳数据,对典型S-N模型的表征能力进行了分析评估。结果表明:Weibull模型、Wu模型和Epaarachchi模型在不同疲劳影响因素下均能表现出较强的拟合能力,整体拟合精度较高,而且Weibull模型和Wu模型具有拟合S-N曲线全区间的能力;Basquin模型虽然在理论和工程中经常使用,但预测精度通常并不理想;相较于不包含应力比的模型,包含应力比的模型其表征精度通常比较差,适用范围反而受限;同时,与半经验模型相比,经验模型通常满足边界条件,对不同形式S-N曲线的拟合优度更高,适应能力更强,且适用范围更广。 展开更多
关键词 复合材料层压板 疲劳 寿命预测 s-N模型 模型评估
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The Level 2 Fuzzy Comprehensive Evaluation Model's Application in 5S
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作者 李鹏翔 赵清 《自动化博览》 2011年第S2期173-177,共5页
Some method on the evaluation of management’s effect should be applied to 5S of manufacturing enterprises’ workshops.To improve traditional methods that are applied to evaluation of management’s effect of those ent... Some method on the evaluation of management’s effect should be applied to 5S of manufacturing enterprises’ workshops.To improve traditional methods that are applied to evaluation of management’s effect of those enterprises,the paper applied the level 2 fuzzy comprehensive evaluation model to the new method and detailedly demonstrated the new method that based on the level 2 fuzzy comprehensive evaluation model with a practical example.In a period of production,managers can easily grasp the macroscopic effect of 5S with the new method,and then make some corresponding measures according to certain actual condition. 展开更多
关键词 FUZZY MATHEMATICs management’s effect COMPREHENsIVE evaluation
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Consistency evaluation of the current distribution of short-circuit tests in AT feeding systems for high-speed railways 被引量:1
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作者 Qing-an Ma Wei Liu 《Journal of Modern Transportation》 2018年第3期163-172,共10页
To improve the accuracy of fault location system, several short-circuit tests need to be conducted before being brought into service in autotransformer (AT) feeding systems for high-speed railways in China. However,... To improve the accuracy of fault location system, several short-circuit tests need to be conducted before being brought into service in autotransformer (AT) feeding systems for high-speed railways in China. However, no systematic algorithm yet exists to evaluate the consistency of the current distribution of short-circuit tests. A methodology is proposed in this paper to address this problem. Based on Kirchhoff’s current law and the generalized method of symmetrical components, the current deviations of the AT feeding systems are analysed and then normalized with the short-circuit current as they vary greatly with systems and short-circuit sites. It is also found that the short-circuit current varies with the calculation methods, and its unbiased standard deviation also reflects the consistency of the short-circuit test. The mean and maximum of the current deviations, as well as the unbiased standard deviation of the short-circuit current, show the consistency of the short-circuit test from different aspects,although the last two items are highly relevant. Therefore, a unified evaluation index is defined as the sum of the three items, and then applied in two case studies to test its performance. The results show that, the proposed index canclearly distinguish the consistency of the short-circuit tests and may be used to sort the short-circuit tests for fault location systems. Besides, some short-circuit tests may have very poor consistency indices, and thus are not applicable to the tuning of fault location systems. In the authors’ opinion, the determination of the threshold of the proposed index needs further investigation. 展开更多
关键词 Autotransformer feeding system short-circuittest Consistency evaluation Kirchhoff’s current law Generalized method of symmetrical components
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基于S-CAD方法的安全生产治本攻坚政策评估 被引量:1
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作者 杨志军 朱启珍 《甘肃行政学院学报》 CSSCI 2024年第3期94-108,128,共16页
国务院安委会牵头发布《安全生产治本攻坚三年行动方案(2024—2026年)》(简称“总政策”),为此,各部门制定了31个部门子方案及部分省级行动实施方案(简称“子政策”),从而形成“1+31+N”的安全生产治本攻坚总体方案。论文运用S-CAD方法... 国务院安委会牵头发布《安全生产治本攻坚三年行动方案(2024—2026年)》(简称“总政策”),为此,各部门制定了31个部门子方案及部分省级行动实施方案(简称“子政策”),从而形成“1+31+N”的安全生产治本攻坚总体方案。论文运用S-CAD方法和NVivo12 Plus软件,对上述政策文本开展量化政策评估。通过系统梳理从目标到结果的逻辑链条,研究发现,总政策与子政策在目标与手段、手段与价值观/立场存在逻辑上的高度一致性,手段对目标的实现上存在较强充分性。在行动方案实施过程中,需要聚焦总政策与子政策的衔接性、政策工具选择的多样性、治理目标的一致性,树立本质安全理念,坚持政府间多部门以及政府、市场与社会多主体双向协同治理,采取行政、市场、法律、社会等多种政策工具,建立事前预防型公共安全治理模式,推进高质量发展和高水平安全良性互动,实现安全生产治理体系和治理能力现代化。 展开更多
关键词 安全生产 治本攻坚行动 s-CAD 政策评估 能力提升
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