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The Interventional Capacity of Community Health Volunteers for Screening and Linkages of Non-Communicable Diseases in Nyeri County, Kenya
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作者 Kenneth Mugambi Jackline Nyaberi Elizabeth Echoka 《Open Journal of Preventive Medicine》 2024年第4期61-78,共18页
Non-communicable diseases (NCDs) account for 63% of mortalities. Approximately 80% of these NCD-related deaths occur in LMICs. A quasi-experimental study utilizing a non-equivalent pre-and post-test was conducted from... Non-communicable diseases (NCDs) account for 63% of mortalities. Approximately 80% of these NCD-related deaths occur in LMICs. A quasi-experimental study utilizing a non-equivalent pre-and post-test was conducted from May 2022 to March 2023 with 370 study participants. Multistage cluster and random sampling were used to select ten community units, and therefore, 150 CHVs were chosen for the control unit, and 150 were used to form the interventional group. Data was collected from the KOBO app. Six (6) homogenous FGDs comprised ten members, and 10 KII were conducted across study sites. Quantitative data was analyzed using SPSS version 28.0, and qualitative data was audio-recorded, transcribed, and analyzed via N-Vivo 12. The study shows that 59.3% of respondents have minimal information, and 92.7% (n = 139) have no clear understanding of NCDs, with a pre-intervention capacity of 48.8%. Independent sample t-test showed a significant difference in capacity from a pre-intervention average of 48.75 (SD ± 5.7)%, which increased to 68.28 (SD ± 7.6)%, p < 0.001. A well-designed community interventional model plays a pivotal role in grassroots healthcare delivery but requires optimization for NCD management. 展开更多
关键词 INTERVENTION Community Health Volunteers Non-Communicable Disease SCREENING linkages
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基于Linkage Mapper的武汉市生态安全格局构建
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作者 严定华 周翔 +2 位作者 包丽艳 杨恩蕾 王鹏程 《城市建筑》 2024年第19期28-33,60,共7页
城市蓝绿空间对维持城市生态平衡具有重要作用,城市化的快速发展促使生态用地破碎化。文章以武汉市为研究对象,基于“生态源地识别—阻力面构建—生态廊道识别—战略节点识别”框架结合连通性构建生态安全格局。结果表明:①生态源地面积... 城市蓝绿空间对维持城市生态平衡具有重要作用,城市化的快速发展促使生态用地破碎化。文章以武汉市为研究对象,基于“生态源地识别—阻力面构建—生态廊道识别—战略节点识别”框架结合连通性构建生态安全格局。结果表明:①生态源地面积共3053.09 km^(2),空间上多集中于武汉市西北部、东南部和东北部。②阻力因子的选取包括土地利用、地形、人为干扰及生态保护四个方面,运用层次分析法得到各阻力因子权重分别为0.387、0.316、0.109和0.188,结合ArcGIS加权得到综合生态阻力值,在空间上呈现“中间高、四周低”的特征。③基于Linkage Mapper识别出生态廊道21条,共计1223.72 km,生态网络结构α指数为0.43、β指数为1.62、γ指数为0.64,重力模型筛选出的作用力大于15的一级廊道共8条。④识别出548个生态夹点,总面积2.7801 km^(2);473处生态障碍点,总面积8.874 km^(2)。 展开更多
关键词 linkage Mapper 生态安全格局 重力模型 MSPA
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Research on the Linkage Effect and Coordinated Development Between Public Libraries Construction and Innovation Efficiency:Theoretical and Empirical Evidence from China
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作者 Jiacheng GAO Yue LIU 《Journal of Systems Science and Information》 CSCD 2024年第5期647-666,共20页
Based on the panel data of 29 provincial administrative regions in China from 2011 to 2022,this study uses the entropy weighting method and the global super-efficiency SBM model to evaluate and measure the public libr... Based on the panel data of 29 provincial administrative regions in China from 2011 to 2022,this study uses the entropy weighting method and the global super-efficiency SBM model to evaluate and measure the public libraries construction level and innovation efficiency in China,uses the vector autoregression model,theαconvergence model and theβconvergence model to evaluate and test whether there is a positive linkage effect between public libraries construction and innovation efficiency,and uses the coupling coordination model to calculate and analyze the coupling coordination degree between public libraries construction and innovation efficiency.The results show that China’s public libraries construction and innovation efficiency are generally in a good development trend,but there is still a large gap from reaching a high level.There is a positive linkage effect between China’s public libraries construction and innovation efficiency,which can not only promote each other’s development,but also drive each other to achieve regional balanced development.The coupling coordination degree between China’s public libraries construction and innovation efficiency is showing a steady upward trend,but it is still on the verge of imbalance as a whole,and the eastern region is significantly better than the central region and western region.The results reveal the positive linkage effect between public libraries construction and innovation efficiency,which has enlightenment significance for building a strong country in culture and innovation.Based on this,this study puts forward suggestions on increasing investment in public libraries construction,optimizing the configuration structure of innovation factors,and strengthening the deep integration of public libraries construction and innovation activities,so as to give full play to the positive linkage effect between public libraries construction and innovation efficiency. 展开更多
关键词 public libraries innovation efficiency linkage effect convergence test coordinated development
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New model of linkage evolution for the transtensional fault systems in the Nanpu Sag of Bohai Bay Basin:Insight from seismic interpretation and analogue modelling
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作者 Yu-Heng Wang Fu-Sheng Yu +1 位作者 Bao-Yin Zhao Ling-Jian Meng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2287-2310,共24页
The evolution of faults within the same stress field is frequently influenced by numerous factors,involving the reactivation of pre-existing structures,stress transmission through ductile detachment layers,and the gro... The evolution of faults within the same stress field is frequently influenced by numerous factors,involving the reactivation of pre-existing structures,stress transmission through ductile detachment layers,and the growth,interaction,as well as linkage of new fault segments.This study analyses a complex multi-phase oblique extension fault system in the Nanpu Sag(NPS)of the Bohai Bay Basin(BBB),China.High-resolution three-dimensional(3D)seismic data and analogue modelling indicate that the oblique extensional reactivation of pre-existing structures governs the sequential arrangement of fault segments in the caprock,and they dip synthetically to the reactivated fault at depth.During the NW-SE extension in the Eocene,the predominant movement of the pre-existing fault is strike-slip.Subsequently,during the N-S extension since the Oligocene,inclined at 20.to the pre-existing fault,forming splay fault segments and ultimately creating large en-echelon arcuate faults linked by relay ramps.Using fault throw-distance(T-D)and laser scanning,we reconstructed the fault evolution model of oblique extension reactivation in the presence of a ductile detachment basement.Our study illustrates that the arcuate faults can be categorized into linear master fault segments controlled by pre-existing structures,bending splay faults in the termination zone,and normal fault segments responding to the regional stress field.The interaction between faults occurs among normal faults and strike-slip faults,and the kinematic unification of the two fault systems is accomplished in the intersection zone.As the faults continue to evolve,the new fault segments tend to relinquish the control of pre-existing structures and concentrate more on the development of planar and continuous major faults.The ductile detachment layer significantly contributes to the uniform distribution of strain,resulting in narrow shear zones and discontinuous normal faults in its absence. 展开更多
关键词 Analogue modelling Transtensional deformation Fault linkage Fault intersection zone Nanpu Sag of Bohai Bay basin
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Spatiotemporal Evolution and Linkage Analysis of Mutton Price in Xinjiang
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作者 Yulin YANG Jian XU Lean YU 《Journal of Systems Science and Information》 CSCD 2024年第5期667-689,共23页
The mutton industry plays a pivotal role in the animal husbandry industry of Xinjiang Uygur Autonomous Region.To better monitor the volatility movement and risk warning of mutton price,the fluctuation characteristics ... The mutton industry plays a pivotal role in the animal husbandry industry of Xinjiang Uygur Autonomous Region.To better monitor the volatility movement and risk warning of mutton price,the fluctuation characteristics of mutton prices and the future trend of prices are analyzed systematically.On the one hand,the Hodrick Prescott(HP)filter method is used to analyze the long-term trends and cyclical characteristics of mutton prices in Xinjiang and explored the spatial evolution characteristics of mutton price fluctuations in various regions of Xinjiang.On the other hand,the Threshold Auto-Regressive(TAR)model is used to analyze the linkage relationship between mutton prices and the prices of other livestock products.The empirical results show that 1)the overall volatility of mutton price in Xinjiang is high,showing a trend of rising first,then falling and then rising from the temporal perspective.2)At the regional level,the price in the south is higher than that of the north,showing a decreasing trend from south to north on the whole from the spatial viewpoint.3)From the linkage relationship perspective,mutton and beef are complementary in the short term,but they are substitutes each other in the long term.This paper explores the characteristics of mutton price fluctuations in Xinjiang from the single time series of mutton prices and the linkage with other livestock products,which provides a reliable basis for the monitoring and risk warning of mutton price fluctuation. 展开更多
关键词 mutton price fluctuation spatiotemporal volution linkage analysis Hodrick Prescott filtering method threshold autoregressive model
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Constructing a Triangular Linkage Model of Government Audit,Social Audit,and Internal Audit to Promote High-Quality Development of Audit Services
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作者 TANG Pengzhan 《Journal of Modern Accounting and Auditing》 2024年第3期89-98,共10页
It is a complex and important topic to study the linkage mechanism of government audit,social audit,and internal audit in the context of China’s high-quality economic development.The implementation of measures,such a... It is a complex and important topic to study the linkage mechanism of government audit,social audit,and internal audit in the context of China’s high-quality economic development.The implementation of measures,such as establishing a sound and perfect organizational safeguard mechanism,strengthening project collaborative audit mechanism,enhancing the mechanism for utilizing audit results,and establishing an audit and rectification joint mechanism can promote the efficient operation of the audit supervision system and the high-quality development of audit services. 展开更多
关键词 government audit social audit internal audit triangular linkage model high-quality development
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基于Linkage Mapper模型的汉江生态城生态廊道构建与修复策略研究
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作者 朱捷缘 徐望朋 +3 位作者 边金云 熊东禹 张忠义 荣月静 《水利规划与设计》 2024年第12期25-30,59,共7页
生态廊道构建对于国土空间格局优化和绿色发展具有重要意义。文章以十堰市汉江生态城为例,以生物多样性维护重要区域为主要生态源地,选取土地覆被类型、地形、坡度、植被指数、距道路距离、距水域距离等因子构建景观综合阻力面,运用Link... 生态廊道构建对于国土空间格局优化和绿色发展具有重要意义。文章以十堰市汉江生态城为例,以生物多样性维护重要区域为主要生态源地,选取土地覆被类型、地形、坡度、植被指数、距道路距离、距水域距离等因子构建景观综合阻力面,运用Linkage Mapper模型构建生态廊道、识别生态障碍点。结果表明:(1)汉江生态城生态源地斑块共39处,面积为232.67km^(2);生态廊道共84条,长度合计108.36km。(2)生态障碍点28个,主要分布在南部和北部的耕地、村镇居民点、采矿用地、林灌植被等地类。(3)建议加强郊野区域农田边界景观营造,对采矿边坡采取绿化覆土种植措施,开展南部园岭山区域中幼林抚育提质,从而提升生境网络连通性。 展开更多
关键词 生态廊道 linkage Mapper模型 生态修复 汉江生态城
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Chronic Hepatitis B in Indian Americans: Lack of Screening and Poor Linkage to Care
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作者 Chul Hyun Soonsik Kim +4 位作者 Emily Li Minhee Lee Mitchell K. Spinnell Joseph McMenamin Dohyun Cho 《International Journal of Clinical Medicine》 CAS 2024年第4期197-209,共13页
Background: Chronic hepatitis B (CHB) is a major cause of liver-related morbidity and mortality in the United States (US) and globally. CHB disproportionately affects Asian Americans and many other immigrant minority ... Background: Chronic hepatitis B (CHB) is a major cause of liver-related morbidity and mortality in the United States (US) and globally. CHB disproportionately affects Asian Americans and many other immigrant minority populations, primarily owing to the high prevalence of CHB in their countries of origin. India is a country with a medium-to-high prevalence of hepatitis B (HB) (>2%) and has over 40 million people infected with hepatitis B virus (HBV), with more than 115,000 deaths annually from HBV-related complications. Indian Americans are one of the largest immigrant populations in the US but remain underdiagnosed and poorly linked to clinical care. We, therefore, assessed the HBV prevalence and evaluated the linkage-to-care (LTC) among Indian Americans to develop strategic plans to reduce the impact of HBV in the US. Methods: Between April 2022 and January 2024, serologic screening and surveys were provided to 328 Indian American adults (age 20 - 80) in New York City. All participants were tested for a triple panel consisting of hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti-HBs), and hepatitis B core IgG antibody (anti-HBc). A survey was conducted on the subjects chronically infected with HBV regarding their histories of infection. Self-administered questionnaires were employed to evaluate demographic and epidemiologic characteristics. Results: Of 328 screened and evaluated (246 males and 82 females), 10 (3.0%) were HBV-infected, 222 (67.7%) were susceptible to HBV, and 96 (29.3%) were immune. The prevalence of chronic HBV varied between the age groups: 4.6% (age 20 - 40), 3.4% (age 41 - 60), and 1.7% (age 61 - 80). Of 10 chronically infected, only two subjects had been previously diagnosed but were not engaged in care. Conclusion: HBV disproportionately affects Asian Americans, primarily owing to immigration from parts of the world where the disease is endemic. Indian Americans belong to an intermediate-risk group, with an HBV prevalence of >2%, but remain underdiagnosed and poorly linked to care. Our pilot study on Indian American populations, the first of its kind, demonstrates a 3% prevalence of CHB, none of whom are linked to care. In addition, this population has a high percentage of unimmune subjects, creating a large reservoir for future infection. With the growing population of Indian Americans, our findings can be used to develop community-based strategies for HBV screenings and LTC that target high-risk groups. 展开更多
关键词 Hepatitis B Virus Chronic Hepatitis B Indian Americans Health Disparity Community-Based Screening linkage-to-Care
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基于MSPA-Linkage Mapper的福州滨海长乐区生态网络构建与优化 被引量:4
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作者 廖剑威 闫淑君 +3 位作者 叶佳伟 杨丽 纪霜 尤泽欣 《西北林学院学报》 CSCD 北大核心 2023年第5期243-251,共9页
构建生态网络是改善城市生态环境和维持生态服务功能的重要举措。以福州市长乐区为例,基于形态空间格局(MSPA)、Linkage Mapper和重力模型提取各级潜在生态廊道及生态节点,构建并优化长乐区生态网络。结果表明:1)基于MSPA识别出所有景... 构建生态网络是改善城市生态环境和维持生态服务功能的重要举措。以福州市长乐区为例,基于形态空间格局(MSPA)、Linkage Mapper和重力模型提取各级潜在生态廊道及生态节点,构建并优化长乐区生态网络。结果表明:1)基于MSPA识别出所有景观类型,核心区面积最大(245.36 km^(2)),占所有景观类型的73.61%,结合核心源地连通性评价,筛选出11个核心生态源地;2)通过Linkage Mapper、重力模型提取研究区潜在生态廊道共32条,1级廊道11条,2级廊道10条,3级廊道11条,主要分布在研究区南北部纵向连接,尚未形成整体的网络连接;3)采用Barrier Mapper、Pinch point综合识别生态节点,1级生态节点17个,2级生态节点12个、3级生态节点8个,确定各类型生态修复关键区域,提出生态暂歇点建设策略。研究结果为长乐区域生态可持续发展及建设生态保护重点区时序性研究提供参考意义。 展开更多
关键词 生态廊道 形态学空间格局(MSPA) linkage Mapper 生态网络 生态节点
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Mobility Analysis of Altmann Overconstrained Linkages by Modified Grübler-Kutzbach Criterion 被引量:7
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作者 LIU Jingfang LI Yanwen HUANG Zhen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第4期638-646,共9页
Developing a general mobility method/formula is a hot topic lasting for more than 150 years in kinematics. It is necessary to apply any mobility method to puzzling overconstrained mechanisms for verification of its ge... Developing a general mobility method/formula is a hot topic lasting for more than 150 years in kinematics. It is necessary to apply any mobility method to puzzling overconstrained mechanisms for verification of its generality. Altmann linkages are such recognized puzzling mechanisms that their mobility analysis is of important significance. A necessary condition for judging a general mobility method is that the method can be fit for Altmann linkages. Firstly, this study classes Altmann linkages into 17 types in terms of the numbers and types of kinematic pairs, and then Altmann overconstrained linkages are further classified into 4 types. Secondly, the mobility of Altmann overconstrained linkages is systematically analyzed by the Modified Grübler-Kutzbach criterion based on screw theory, where passive freedoms are defined as limb passive freedoms and mechanism passive freedoms. In addition, the full-cycle mobility is judged, which overcomes the shortcoming of instantaneous property of screw theory. It is shown that Modified Grübler-Kutzbach criterion not only obtains the correct numerical mobility, but also gives the mobility character by resolving reciprocal screws for the constraint system. This study lays the foundation of verification for the generality of Modified Grübler-Kutzbach criterion. Besides, Altmann overconstrained linkages almost comprise all kinds of modern parallel mechanisms and some classical mechanisms, which provides an important reference for mechanism mobility calculation. 展开更多
关键词 mobility analysis overconstrained linkage screw theory
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General Order Principle for Multi-Bennett Linkages 被引量:6
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作者 LIU Jingfang YU Yueqing +1 位作者 HUANG Zhen HUANG Xiao'ou 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第2期275-281,共7页
Order analysis for multi-Bennett linkages is a difficult topic in kinematics. Traditional methods fail to obtain the order of multi-Bennett linkages due to considering the special geometric distributions among joint a... Order analysis for multi-Bennett linkages is a difficult topic in kinematics. Traditional methods fail to obtain the order of multi-Bennett linkages due to considering the special geometric distributions among joint axes. An order principle for multi-Bennett linkages is presented. For a summated multi-Bennett linkage, three procedures are included in the order principle. Firstly, a homogeneous screw equation is obtained by taking linear superposition operations and then the maximum order is determined according to linear dependency of all screws. Secondly, two theorems are employed to determine the maximum order, where the first is used to judge the linear independency of four-system screws and the second is fit for identifying the linear independency of five-system screws. Lastly, all possible cases in the order range are considered until the valid order is screened out. For a syncopated multi-Bennett linkage, an equivalent summated model is built and then the order analysis is the same as that of summated linkages. In order to verify the effectiveness of the presented order principle, the orders of summated 5R and 6R linkages as well as a syncopated 6R linkage are analyzed. The computed orders of the former two summated linkages are both 4 and the computed order of the last syncopated 6R linkage is 5. The results coincide with the prototype data. The advantage of the proposed principle is that it can get the correct order of a multi-Bennett linkage without solving the geometric conditions of joint axes and has wide application in variety of multi-Bennett linkages. 展开更多
关键词 Order analysis Multi-Bennett linkage Homogeneous screw equation Screw theory
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DYNAMIC DESIGN OF VARIABLE SPEED PLANAR LINKAGES 被引量:5
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作者 YaoYanan YanHongsen ZouHuijun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第1期51-54,共4页
A method for improving dynamic characteristics of planar linkages by activelyvarying the speed function of the input link is presented. Design criteria and constraints for thedynamic design of variable speed planar li... A method for improving dynamic characteristics of planar linkages by activelyvarying the speed function of the input link is presented. Design criteria and constraints for thedynamic design of variable speed planar linkages are developed. Both analytical and optimizationapproaches for determining suitable input speed functions to minimize the driving torque, theshaking moment, or both simultaneously of planar linkages, subject to various design requirementsand constraints, are derived. Finally, some examples are given to illustrate the design procedureand to verify its feasibility. 展开更多
关键词 Planar linkage Driving torque Shaking moment
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基于Linkage Mapper与复杂网络的成都市生态网络构建与优化 被引量:7
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作者 田硕娟 张文君 +2 位作者 何灵 缪骏懿 訾应昆 《西北林学院学报》 CSCD 北大核心 2023年第3期176-184,共9页
城市化速度加快,城镇内部生态斑块破碎,生态廊道隔断,区域可持续发展受到阻碍。构建生态网络可以连接破碎斑块,保护生物多样性与地域特色。以成都市为例,基于形态学空间格局分析(morphological spatial pattern analysis, MSPA)方法并... 城市化速度加快,城镇内部生态斑块破碎,生态廊道隔断,区域可持续发展受到阻碍。构建生态网络可以连接破碎斑块,保护生物多样性与地域特色。以成都市为例,基于形态学空间格局分析(morphological spatial pattern analysis, MSPA)方法并结合景观连通度指数确定生态源地,从地形、景观结构、人类活动三方面确定阻力因子来构建综合阻力面,基于ArcGIS水文分析原理和linkageMapper识别生态廊道和生态节点,利用复杂网络增边优化理论,对研究区处于高阻力值且介中心性低的点进行模拟增边,最后对比增边前后的稳定性,验证增边效果。结果表明:1)成都市生态源地主要分布在西部林区,东部和中部较为稀疏。2)成都市阻力值呈现由中部向外部降低趋势,中心都市圈阻力值最高。3)基于GIS共提取111条生态廊道、209条辐射道、101个生态节点。4)识别出增边优化节点8个,成功模拟增加11条生态廊道,模拟增边优化后网络稳定性明显提升,网络连通性增强,网络结构整体更为稳定。 展开更多
关键词 生态廊道 生态节点 生态网络 linkage Mapper(LM) 复杂网络 稳定性
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Phase-Division-Based Dynamic Optimization of Linkages for Drawing Servo Presses 被引量:4
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作者 Zhi-Gang Zhang Li-Ping Wang Yan-Ke Cao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第6期1426-1437,共12页
Existing linkage-optimization methods are designed for mechanical presses; few can be directly used for servo presses, so development of the servo press is limited. Based on the complementarity of linkage opti- mizati... Existing linkage-optimization methods are designed for mechanical presses; few can be directly used for servo presses, so development of the servo press is limited. Based on the complementarity of linkage opti- mization and motion planning, a phase-division-based linkage-optimization model for a drawing servo press is established. Considering the motion-planning principles of a drawing servo press, and taking account of work rating and efficiency, the constraints of the optimization model are constructed. Linkage is optimized in two modes: use of either constant eccentric speed or constant slide speed in the work segments. The performances of optimized link- ages are compared with those of a mature linkage SL4- 2000A, which is optimized by a traditional method. The results show that the work rating of a drawing servo press equipped with linkages optimized by this new method improved and the root-mean-square torque of the servo motors is reduced by more than 10%. This research pro- vides a promising method for designing energy-saving drawing servo presses with high work ratings. 展开更多
关键词 Drawing servo press linkage optimization Phase-division Motion planning
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The Belt and Road Initiative and the 2030 Agenda for Sustainable Development:seeking linkages for global environmental governance 被引量:5
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作者 Liang Dong Xiaohua Yang Hongtao Li 《Chinese Journal of Population,Resources and Environment》 2018年第3期203-210,共8页
Global environmental cooperation serves as an important part in the Chinese ideal of building a Community with a Shared Future for all Human Beings. The report of 19 th CPC National Congress indicates that China is co... Global environmental cooperation serves as an important part in the Chinese ideal of building a Community with a Shared Future for all Human Beings. The report of 19 th CPC National Congress indicates that China is committed to proactive mitigation under the Paris Agreement and further participating in global environmental governance under the 2030 Agenda for Sustainable Development, and both of which are largely integrated to the Belt and Road Initiative(BRI). BRI are also closely linked with South-South environmental and climate cooperation proposed by China from previous UN summits. Based on shared ideas, intersected agendas, and compatible governance approaches, BRI and the 2030 Agenda for Sustainable Development grow increasingly relevant and they might form synergies based on increasingly interactive relations. In sum,seeking and intensifying the linkages between BRI and 2030 sustainable development goals(SDGs) could address global environmental governance deficits and enhance cooperation among nations. 展开更多
关键词 The BELT and ROAD INITIATIVE 2030 AGENDA for Sustainable Development South-South cooperation INTERPLAY global environmental governance linkage climate change
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Urban Hierarchy of Innovation Capability and Inter-city Linkages of Knowledge in Post-reform China 被引量:22
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作者 LU Lachang HUANG Ru 《Chinese Geographical Science》 SCIE CSCD 2012年第5期602-616,共15页
The 2000s has witnessed increasing interests in cities′role of innovation in the era of knowledge-based economy.Compared with substantial empirical analysis on the world city hierarchy of innovation,this paper attemp... The 2000s has witnessed increasing interests in cities′role of innovation in the era of knowledge-based economy.Compared with substantial empirical analysis on the world city hierarchy of innovation,this paper attempts to examine the national urban hierarchy of innovation capability in China,in terms of ranking systems,spatial pattern and inter-city linkages of knowledge during the post-reform period since the late 1970s.Based on quantitative analysis such as principal component factor analysis and clustering analysis,this paper identifies the five-tier hierarchy of in-novation,which is headed by Beijing and Shanghai,followed by the capital cities of each province and regional centre cities.The development of China′s urban hierarchy of innovation capability has been driven by such factors as the scale of innovation,scientific scale,innovation potential and innovation environment.The paper further investigates the inter-city linkages of knowledge measured by the number of co-authored papers among the cities.Beijing is positioned in the central position of the knowledge diffusion and knowledge cooperation innovation.More knowledge diffusion among high level cities has occurred than that among the low level cities as well as between the low level cities and high level cities,and provincial capital cities and the regional central cities. 展开更多
关键词 urban hierarchy innovation capability inter-city linkages of knowledge Chinese cities
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IMPROVED HOMOTOPY ITERATION METHOD AND APPLIED TO THE NINE-POINT PATH SYNTHESIS PROBLEM FOR FOUR-BAR LINKAGES 被引量:1
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作者 Zhang Jian Chen Yong (School of Mechanical Engineering, Southwest Jiaotong University) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2000年第1期10-16,共7页
A new algorithm called homotopy iteration method based on the homotopy function is studied and improved. By the improved homotopy iteration method, Polynomial systems with high Order and deficient can be solved fast a... A new algorithm called homotopy iteration method based on the homotopy function is studied and improved. By the improved homotopy iteration method, Polynomial systems with high Order and deficient can be solved fast and efficiently comparing to the original homotopy iteration method. Numerical examples for the ninepoint path synthesis of four-bar linkages show the advantages and efficiency of the improved homotopy iteration method. 展开更多
关键词 Homotopy function Homotopy iteration method Nine-point path synthesis Four-bar linkage
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SUPERHARMONIC RESONANCES OF ELASTIC LINKAGES UNDER HAMONIC EXCITATION 被引量:1
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作者 王玉新 储景云 张策 《Transactions of Tianjin University》 EI CAS 1995年第1期53+48-53,共7页
Considering the geometric nonlinearity due to the large elastic deformations of flexible links, the superharmonic resonances of elastic linkages in the forms of ω1/3 and ω1/2 are studied by the method of multiple sc... Considering the geometric nonlinearity due to the large elastic deformations of flexible links, the superharmonic resonances of elastic linkages in the forms of ω1/3 and ω1/2 are studied by the method of multiple scales. The research shows that the analytical results are coincident with the experimental results. 展开更多
关键词 elastic linkages geometric nonlinearity superharmonic resonances
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CALCULATION OF NATURAL FREQUENCIES FOR THE PLANAR SIX-BAR LINKAGE OF WATT TYPE
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作者 张代昌 刘小豹 《Journal of China Textile University(English Edition)》 EI CAS 1991年第3期49-57,共9页
By using transfer matrix,the lower-order natural frequencies of the Watt type planar six-barlinkage are calculated in this paper.The experiment of the modal analysis is done with the SignalProcessor 7T17S,and the expe... By using transfer matrix,the lower-order natural frequencies of the Watt type planar six-barlinkage are calculated in this paper.The experiment of the modal analysis is done with the SignalProcessor 7T17S,and the experiment results agree with the calculated ones.This method only re-quires calculation of lower-order transfer matrix and determinant values,so that, it can be done ona minicomputer such as IBM/PC.The method adopted in this paper is also suitable for vibrationanalysis of other types of linkages. 展开更多
关键词 vibration ANALYSIS transfer matrix modal ANALYSIS FUR SEWING machine bend needle mechanism PLANAR linkagE six-bar linkagE of Watt TYPE
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A Study on Six-Bar Linkage Knee Prosthesis 被引量:1
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作者 Ruihong Zhang Linhong Ji +2 位作者 Dewen Jin Jichuan Zhang Caiqin Bai(Department of Precision Instruments, Tsinghua University Beijing 100084, China) 《Chinese Journal of Biomedical Engineering(English Edition)》 1999年第3期5-6,共2页
关键词 A Study on six-bar linkage Knee Prosthesis
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