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Can whole steps of grain production be outsourced? Empirical analysis based on the three provinces of Jiangsu,Jilin,and Sichuan in China
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作者 Jiacheng Liu Shengzhi Mao +1 位作者 Qiufen Zheng Zhigang Xu 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期336-347,共12页
Certain outsourcing services for agricultural management in China,such as pest control in grain production,have experienced prolonged sluggishness,contrasting with the relatively high level of outsourcing services obs... Certain outsourcing services for agricultural management in China,such as pest control in grain production,have experienced prolonged sluggishness,contrasting with the relatively high level of outsourcing services observed in harvesting,land preparation,and sowing.This study examines the feasibility of implementing whole-step outsourcing in grain production by conducting a case study of rice and maize production in Jiangsu,Jilin,and Sichuan provinces in China.The provision of outsourcing services hinges on two essential conditions:technological advancements fostering specialized production and economies of scale,coupled with a market size sufficient to realize the aforementioned potential economies of scale.The results showed that outsourcing pest control or harvesting services had varying economies of scale.The outsourcing services in pest control were less common than in harvesting services,and their marginal growth space of the economies of scale with technological change was also smaller.Determined by the operational characteristics of pest control itself,the market scale of its professional services is small.Therefore,achieving the whole-step outsourcing of grain production necessitates not only technological innovation but also effective policy interventions to overcome the constraints of market scale.Such interventions include(1)optimizing crop layouts between planning regions and reducing land fragmentation and(2)supplying timely and effective inter-regional agricultural information for service providers aided by information technology. 展开更多
关键词 outsourcing services economy of scale technical conditions market scale
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Validity,Reliability,and Measurement Invariance of the Thai Smartphone Application-Based Addiction Scale and Bergen Social Media Addiction Scale
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作者 Kamolthip Ruckwongpatr Chirawat Paratthakonkun +8 位作者 Usanut Sangtongdee Iqbal Pramukti Ira Nurmala Kanokwan Angkasith Weena Thanachaisakul Jatuphum Ketchatturat Mark DGriffiths Yi-Kai Kao Chung-Ying Lin 《International Journal of Mental Health Promotion》 2024年第4期293-302,共10页
Background:In recent years,there has been increased research interest in both smartphone addiction and social media addiction as well as the development of psychometric instruments to assess these constructs.However,t... Background:In recent years,there has been increased research interest in both smartphone addiction and social media addiction as well as the development of psychometric instruments to assess these constructs.However,there is a lack of psychometric evaluation for instruments assessing smartphone addiction and social media addiction in Thailand.The present study evaluated the psychometric properties and gender measurement invariance of the Thai version of the Smartphone Application-Based Addiction Scale(SABAS)and Bergen Social Media Addiction Scale(BSMAS).Method:A total of 801 Thai university students participated in an online survey from January 2022 to July 2022 which included demographic information,SABAS,BSMAS,and the Internet Gaming Disorder Scale-Short Form(IGDS9-SF).Results:Confirmatory Factor Analyses(CFAs)found that both the SABAS and BSMAS had a one-factor structure.Findings demonstrated adequate psychometric properties of both instruments and also supported measurement invariance across genders.Moreover,scores on the SABAS and BSMAS were correlated with scores on the IGDS9-SF.Conclusion:The results indicated that the SABAS and BSMAS are useful psychometric instruments for assessing the risk of smartphone addiction and social media addiction among Thai young adults. 展开更多
关键词 Factor analysis smartphone addiction social media addiction smartphone application-based addiction scale bergen social media addiction scale psychometric validation
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Path Analysis of High-Quality Development of Regional Economy The Role and Impact of Industrial Policies
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作者 Nan Zhou 《Proceedings of Business and Economic Studies》 2024年第2期198-204,共7页
With China’s economic development entering a new normal,high-quality regional economic development has become an important goal of current economic development.As one of the important means to promote high-quality de... With China’s economic development entering a new normal,high-quality regional economic development has become an important goal of current economic development.As one of the important means to promote high-quality development of the regional economy,industrial policies are increasingly receiving attention in terms of their role and impact.This article mainly conducts an in-depth analysis of the mechanism and impact path of industrial policies,exploring the role and impact of industrial policies in promoting high-quality regional economic development.Firstly,industrial policies play an important role in promoting high-quality regional economic development.Secondly,the impact path of industrial policies on the high-quality development of the regional economy mainly includes promoting industrial structure upgrading,promoting technological innovation,guiding resource allocation,and enhancing enterprise competitiveness.Therefore,it is necessary to increase research and practice on industrial policies,continuously optimize policy measures,and promote high-quality development of the regional economy. 展开更多
关键词 Industrial policy Regional economy High-quality development Path analysis
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Study on the Influence of Lanzhou-Urumqi High-Speed Railway on Regional Accessibility and Economic Development
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作者 Lili Ma Xiaolong Han Miao Gong 《Proceedings of Business and Economic Studies》 2024年第2期22-31,共10页
The Lanzhou-Urumqi high-speed railway is an important part of the railway network connecting Gansu,Qinghai,and Xinjiang,and it is of far-reaching significance in facilitating China’s western development.An accessibil... The Lanzhou-Urumqi high-speed railway is an important part of the railway network connecting Gansu,Qinghai,and Xinjiang,and it is of far-reaching significance in facilitating China’s western development.An accessibility model and a double difference model were built to analyze the impact of the Lanzhou-Urumqi high-speed railway on regional accessibility and economic development of the areas along the line before(2012-2014)and after(2017-2019)its opening.The results show that the regional accessibility remains unchanged before and after the operation of this railway line.However,there is a spatial difference in improvement,that of central cities being better.The opening of the high-speed railway is conducive to driving the overall economic development of the region and promoting the comprehensive and coordinated development of regional economies. 展开更多
关键词 Lanzhou-Urumqi high-speed railway Regional economy Double difference model Accessibility model Empirical analysis
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Factor Structure and Measurement Invariance of the Japanese Version of the Mother-to-Infant Bonding Scale
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作者 Mami Yamamoto Fumie Takauma +2 位作者 Katsuhiko Tada Kaori Baba Toshinori Kitamura 《Advances in Reproductive Sciences》 2023年第4期159-170,共12页
Background: Bonding disorders affect the growth and development of infants. In Japan, the Japanese version of the Mother-to-Infant Bonding Scale (MIBS-J) is widely used for early detection of bonding disorders. Repeat... Background: Bonding disorders affect the growth and development of infants. In Japan, the Japanese version of the Mother-to-Infant Bonding Scale (MIBS-J) is widely used for early detection of bonding disorders. Repeated use of a questionnaire has problems of reduced validity. In order to correctly detect bonding disorders at multiple time points, it is necessary to confirm the measurement invariance of the scale. Baba et al. reported that invariance of the MIBS-J factor structure could only be obtained by abridging the scale into three items. Purpose: The aim of this study was to 1) confirm the factor structure and measurement invariance of the MIBS-J between two measurement times and 2) to examine factors that can be used without being affected by measurement time in order to identify item that contribute to measure met invariance. Methods: We analysed the data of 1049 and 878 mothers with a neonate collected in two waves: 5 days (Wave 1) and 1 month postpartum (Wave 2). Exploratory and confirmatory factor analyses were conducted on the data randomly divided into two groups in each wave. Results: The three-item model (MIBS-J items 1, 6, and 8) was most accepted. Measurement invariance and structural invariance were confirmed in the model. This was consistent with Baba et al.’s model. Conclusion: The three MIBS-J items showed measurement invariance and structural invariance in Japanese mothers during 1 month postpartum. 展开更多
关键词 Bonding Disorders Mother-to-Infant Bonding scale Factor analysis Measurement Invariance
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A Note on an Economic Lot-sizing Problem with Perishable Inventory and Economies of Scale Costs:Approximation Solutions and Worst Case Analysis 被引量:2
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作者 Qing-Guo Bai Yu-Zhong Zhang Guang-Long Dong 《International Journal of Automation and computing》 EI 2010年第1期132-136,共5页
This paper presents an economic lot-sizing problem with perishable inventory and general economies of scale cost functions. For the case with backlogging allowed, a mathematical model is formulated, and several proper... This paper presents an economic lot-sizing problem with perishable inventory and general economies of scale cost functions. For the case with backlogging allowed, a mathematical model is formulated, and several properties of the optimal solutions are explored. With the help of these optimality properties, a polynomial time approximation algorithm is developed by a new method. The new method adopts a shift technique to obtain a feasible solution of subproblem and takes the optimal solution of the subproblem as an approximation solution of our problem. The worst case performance for the approximation algorithm is proven to be (4√2 + 5)/7. Finally, an instance illustrates that the bound is tight. 展开更多
关键词 Economic lot-sizing problem BACKLOGGING economies of scale function PERISHABLE approximation algorithm
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The Scale Benefit Analysis of Sugar Clusters in Resource-rich Area of Southweatern Guangxi——A Case of Chongzuo City
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作者 MA Chang-gang Guangxi Normal University for Nationalities,Chongzuo 532200,China 《Asian Agricultural Research》 2011年第3期15-19,共5页
Based on the scope economic theory of "resource curse" and industrial clusters,the scale of sugar cluster is calculated by the output of sugarcane and sugar while the scale benefit of sugar cluster is measur... Based on the scope economic theory of "resource curse" and industrial clusters,the scale of sugar cluster is calculated by the output of sugarcane and sugar while the scale benefit of sugar cluster is measured by the productivity(rate of sugar production),sales output ratio,industrial output value as well as profit margin.Positive analysis of the scale merit of sugar clusters in resource-rich area of southwestern Guangxi is conducted according to related statistics of Chongzuo City.And the primary problems of sugar clusters are pointed out.The profit created by sugar for the sugar industry in Chongzuo City has already been near capacity.The sugar industry is big but not strong.With much governmental interfernce,there is no effective connections and inadequte competitive forces among subjects of the clusters.The extention of industrial chain is limited.Therefore,measures for developing sugar clusters in resource-rich area of southwestern Guangxi are proposed.Industrial structure is to be adjusted to improve the sugarcane cultivation techniques.The industrial chain should be extended to increase the economic benefits of sugar industry.Industrial support is to be strengthened and capital output for sicence and technology increased.Price regualtion fund of grain sugar is to be established with coordination with the superior region.The transformation from savings to investment should be quickened to evade "resource curse". 展开更多
关键词 RESOURCE-RICH SUGAR CLUSTERS scale ECONOMY BENEFIT
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Temporal and Spatial Scale Dependence of Precipitation Analysis over the Tropical Deep Convective Regime
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作者 沈新勇 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2012年第6期1390-1394,共5页
Data from Goddard cumulus ensemble model experiment are used to study temporal and spatial scale dependence of tropical rainfall separation analysis based on cloud budget during Tropical Ocean Global Atmosphere Couple... Data from Goddard cumulus ensemble model experiment are used to study temporal and spatial scale dependence of tropical rainfall separation analysis based on cloud budget during Tropical Ocean Global Atmosphere Coupled Ocean Atmosphere Response Experiment (TOGA COARE). The analysis shows that the calculations of model domain mean or time-mean grid-scale mean simulation data overestimate the rain rates of the two rainfall types associated with net condensation but they severely underestimate the rain rate of the rainfall type associated with net evaporation and hydrometeor convergence. 展开更多
关键词 cloud microphysical budget temporal and spatial scale rainfall partitioning analysis
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Ecological Network Analysis Quantifying the Sustainability of Regional Economies: A Case Study of Guangdong Province in China 被引量:2
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作者 LIANG Jinshe HU Ke DAI Teqi 《Chinese Geographical Science》 SCIE CSCD 2018年第1期127-136,共10页
To meet the challenge of sustainable development, sustainability must be made. Ecological network analysis(ENA) was introduced in this paper as an approach to quantitatively measure the growth, development, and sustai... To meet the challenge of sustainable development, sustainability must be made. Ecological network analysis(ENA) was introduced in this paper as an approach to quantitatively measure the growth, development, and sustainability of an economic system. The Guangdong economic networks from 1987 to 2010 were analyzed by applying the ENA approach. Firstly, a currency flow network among economic sectors was constructed to represent the Guangdong economic system by adapting the input-output(I-O) table data. Then, the network indicators from the ENA framework involving the total system throughput(TST), average mutual information(AMI), ascendency(A), redundancy(R) and development capacity(C) were calculated. Lastly, the network indicators were analyzed to acquire the overall features of Guangdong's economic operations during 1987–2010. The results are as follows: the trends of the network indicators show that the size of the Guangdong economic network grows exponentially at a high rate during 1987–2010, whereas its efficiency does not present a clear trend over its whole period. The growth is the main characteristic of the Guangdong economy during 1987–2010, with no clear evidence regarding its development. The quantitative results of the network also confirmed that the growth contributed to a great majority of the Guangdong economy during 1987–2010, whereas the development's contribution was tiny during the same period. The average value of the sustainability indicator(α) of the Guangdong economic network was 0.222 during 1987–2010, which is less than the theoretically optimal value of 0.37 for a sustainable human-influenced system. The results suggest that the Guangdong economic system needs a further autocatalysis to improve its efficiency to support the system maintaining a sustainable evolvement. 展开更多
关键词 经济系统 网络分析 可持续性 广东省 生态 地区性 案例 中国
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Analysis of a Group of Weak Small-Scale Vortexes in the Planetary Boundary Layer in the Mei-yu Front 被引量:13
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作者 翟国庆 周玲丽 王智 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第3期399-408,共10页
A mei-yu front process in the lower reaches of the Yangtze River on 23 June 1999 was simulated by using the fifth-generation Pennsylvania State University-NCAR (PSU/NCAR) Mesoscale Model (MM5) with FDDA (Four Dim... A mei-yu front process in the lower reaches of the Yangtze River on 23 June 1999 was simulated by using the fifth-generation Pennsylvania State University-NCAR (PSU/NCAR) Mesoscale Model (MM5) with FDDA (Four Dimension Data Assimilation). The analysis shows that seven weak small mesoscale vortexes of tens of kilometers, correspondent to surface low trough or mesoscale centers, in the planetary boundary layer (PBL) in the mei-yu front were heavily responsible for the heavy rainfall. Sometimes, several weak small-scale vortexes in the PBL could form a vortex group, some of which would weaken locally, and some would develop to be a meso-α-scale low vortex through combination. The initial dynamical triggering mechanism was related to two strong currents: one was the northeast flow in the PBL at the rear of the mei-yu front, the vortexes occurred exactly at the side of the northeast flow; and the other was the strong southwest low-level jet (LLJ) in front of the Mei-yu front, which moved to the upper of the vortexes. Consequently, there were notable horizontal and vertical wind shears to form positive vorticity in the center of the southwest LLJ. The development of mesoscale convergence in the PBL and divergence above, as well as the vertical positive vorticity column, were related to the small wind column above the nose-shaped velocity contours of the northeast flow embedding southwestward in the PBL, which intensified the horizontal wind shear and the positive vorticity column above the vortexes, baroclinicity and instability. 展开更多
关键词 mei-yu front heavy rainfall mesoscale numerical simulation FDDA meso-β-scale vortexes group physical diagnosis and analysis
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Efficiency Comparison and Influencing Factor Analysis of Dairy Farms over/at Different Scales:Based on the Survey Data of 263 Scale Farms in 22 Provinces of China
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作者 Jing WANG Xiaoxia DONG +3 位作者 Hua PENG Jing ZHANG Chao ZHANG Hao LIU 《Asian Agricultural Research》 2021年第7期1-8,共8页
China's dairy farming has presented a striking development in recent years.Under the dual constraints of environment and resources,it is of practical significance to increase the output of dairy farming and ensure... China's dairy farming has presented a striking development in recent years.Under the dual constraints of environment and resources,it is of practical significance to increase the output of dairy farming and ensure the healthy and stable development of the dairy industry,by accurately comparing the differences in the farming efficiency of dairy farms at different scales and grasping key factors influencing the farming efficiency.This study,through the cost analysis of 263 scale farms across 23 provinces and regions of China in 2019,reaches a result that the cost of a single cow in a certain scale farm increases with the enlargement of the scale,and shows an inverted-U shaped curve with the relatively large scales(1001-2000 cows)at the highest point.It measures the farming efficiency of dairy farms at different scales through the data envelopment analysis and finds that the scale efficiency and allocation efficiency of scale farms in China are relatively high,while the technology efficiency and cost efficiency are relatively low.The efficiency of different scale farms is obviously different,where the cost efficiency,allocation efficiency and scale efficiency show a U-shaped curve as the scale enlarges(with the relatively large scale as the lowest point),while the technology efficiency gradually decreases as the scale expands.It is concluded that for the scale farms,feed conversion ratio and forage-to-concentrate ratio have a significantly negative impact on the scale efficiency,while the labor cost,number of employees,and depreciation of fixed assets are negatively correlated to the technology efficiency and cost efficiency of dairy farming. 展开更多
关键词 Data envelopment analysis Farming efficiency Influencing factor scale farm
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The Spatial Sensitivity Analysis of Evapotranspiration using Penman-Monteith Method at Grid Scale
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作者 Sivarajah Mylevaganam Chittaranjan Ray 《Journal of Geographic Information System》 2016年第1期121-136,共16页
The need to allocate the existing water in a sustainable manner, even with the projected population growth, has made to assess the consumptive use or evapotranspiration (ET), which determines the irrigation demand. As... The need to allocate the existing water in a sustainable manner, even with the projected population growth, has made to assess the consumptive use or evapotranspiration (ET), which determines the irrigation demand. As underscored in the literature, Penman-Monteith method which is a combination of aerodynamic and energy balance method is widely used and accepted as the method of estimation of ET. However, the application of Penman-Monteith relies on many climate parameters such as relative humidity, solar radiation, temperature, and wind speed. Therefore, there exists a need to determine the parameters that are most sensitive and correlated with dependent variable (i.e., ET), to strengthen the knowledge base. However, the sensitivity of ET using Penman-Monteith is oftentimes estimated using meteorological data from climate stations. Such estimation of sensitivity may vary spatially and thus there exists a need to estimate sensitivity of ET spatially. Thus, in this paper, based on One-AT-A-Time (OAT) method, a spatial sensitivity tool that can geographically encompass all the best available climate datasets to produce ET and its sensitivity at different spatial scales is developed. The spatial tool is developed as a Python toolbox in ArcGIS using Python, an open source programming language, and the ArcPy site-package of ArcGIS. The developed spatial tool is demonstrated using the meteorological data from Automated Weather Data Network in Nebraska in 2010. To summarize the outcome of the sensitivity analysis using OAT method, sensitivity indices are developed for each raster cell. The demonstration of the tool shows that, among the considered parameters, the computed ET using Penman-Monteith is highly sensitive to solar radiation followed by temperature for the state of Nebraska, as depicted by the sensitivity index. The computed sensitivity index of wind speed and the relative humidity are not that significant compared to the sensitivity index of solar radiation and temperature. 展开更多
关键词 EVAPOTRANSPIRATION Penman-Monteith Method Aerodynamic Method Energy Balance Method PYTHON ArcPy ArcGIS Spatial scale GEOPROCESSING Python Toolbox Sensitivity analysis One-AT-A-Time Sensitivity Index
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Suitability Analysis of Scale Management in Northeast China Based on Efficiency Evaluation 被引量:2
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作者 Wenxin LIU Xiuli HE 《Asian Agricultural Research》 2018年第10期30-34,共5页
Under the resource constraint of low per capita possession of cultivated land and the strategic requirements for ensuring national food security,the intensive and efficient use of cultivated land is an important topic... Under the resource constraint of low per capita possession of cultivated land and the strategic requirements for ensuring national food security,the intensive and efficient use of cultivated land is an important topic for long-term research in China's academic circles. It is an important prerequisite for exploring the moderate scale management of agricultural land. The calculation results of 147 county-level units in Northeast China by DEA method show that in the use efficiency evaluation results of cultivated land of county-level units,the mean values of comprehensive efficiency,pure technical efficiency and scale efficiency were 0. 674,0. 705 and 0. 96,respectively,and the DEA effective units account for about 11%. The effective areas of pure technical efficiency and scale efficiency do not have a high level of superposition. To a certain extent,this also limits the improvement of overall efficiency. In view of the scale of family farmland management,counties and cities with an average per household possession of cultivated land of 1. 71-2. 13 ha can achieve both scale and efficiency through efficiency improvement. 展开更多
关键词 人均占有耕地 中国 粮食安全 农业
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Numerical Analysis of the Adhesive Forces in Nano-Scale Structure 被引量:1
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作者 Young-Sam Cho Houkseop Han Wan-Doo Kim 《Journal of Bionic Engineering》 SCIE EI CSCD 2006年第4期209-216,共8页
Nanohairs, which can be found on the epidermis of Tokay gecko's toes, contribute to the adhesion by means of van der Waals force, capillary force, etc. This structure has inspired many researchers to fabricate the at... Nanohairs, which can be found on the epidermis of Tokay gecko's toes, contribute to the adhesion by means of van der Waals force, capillary force, etc. This structure has inspired many researchers to fabricate the attachable nano-scale structures. However, the efficiency of artificial nano-scale structures is not reliable sufficiently. Moreover, the mechanical parameters related to the nano-hair attachment are not yet revealed qualitatively. The mechanical parameters which have influence on the ability of adhesive nano-hairs were investigated through numerical simulation in which only van der Waals force was considered. For the numerical analysis, finite element method was utilized and van der Waals force, assumed as 12-6 Lennard-Jones potential, was implemented as the body force term in the finite element formulation. 展开更多
关键词 NUMERICAL analysis adhesive force nano-scale structure finite element model van der Waals force 12-6 L-J potential
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An Assessment Scale for Evaluating the Experimental Design Ability of Elementary Science Teachers Based on Primary Trait Analysis
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作者 Saiqi Tian Jinxing Zhu +1 位作者 Chuyin Chen Zhiqing Wang 《Journal of Contemporary Educational Research》 2022年第3期12-20,共9页
In this study,an assessment scale for evaluating the experimental design ability of elementary science teachers was constructed based on primary trait analysis.This assessment scale contains three first-level indexes ... In this study,an assessment scale for evaluating the experimental design ability of elementary science teachers was constructed based on primary trait analysis.This assessment scale contains three first-level indexes and eleven second-level indexes.The corresponding weights of indexes were determined by the objective weighting method.The scores of all the descriptions of the indexes were also assigned.After a trial test,this assessment scale was verified to be reliable and valid for evaluating the experimental design ability of elementary science teachers. 展开更多
关键词 Assessment scale Experimental design ability Elementary science teachers Primary trait analysis
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Research on Prediction of the Scale of OTC Drug Market in China Based on Quantitative Analysis
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作者 Xu Yang Xu Lang Xue Aoming 《Asian Journal of Social Pharmacy》 2020年第3期145-152,共8页
Objective To analyze the scale of domestic OTC drug market and its influencing factors,so as to predict its future market and provide a scientific basis for pharmaceutical enterprises to grasp the opportunities in the... Objective To analyze the scale of domestic OTC drug market and its influencing factors,so as to predict its future market and provide a scientific basis for pharmaceutical enterprises to grasp the opportunities in the market.Methods The scale of OTC drug market from 1999 to 2018 in China and its influencing factors were analyzed by unit root test,Granger causality test and co-integration test.Results and Conclusion From the perspective of the global pharmaceutical market,OTC drug market has broad prospects and great development potential.Since the influence of GDP and the number of elderly populations on the scale of OTC drug market is positive,the predicted growth rate of OTC market in the next three years is 5.82%,5.86%and 5.90%,respectively. 展开更多
关键词 quantitative analysis OTC drugs prediction of the scale of market unit root test granger causality test co-integration test
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THE "STRUCTURE-STRATIGRAPHY ANALYSIS" METHOD APPLIED IN THE PREDICTION OF SMALLER-SCALED STRUCTURE IN UNDERGROUND MINING
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作者 李增学 魏久传 李守春 《Journal of Coal Science & Engineering(China)》 1996年第1期61-66,共6页
Structure-stratigraphy analysis" is a new method used in the study and prediction of and small-scaled structures in coal mines. The object of this method is coalbed structure that includes the folds and fracture ... Structure-stratigraphy analysis" is a new method used in the study and prediction of and small-scaled structures in coal mines. The object of this method is coalbed structure that includes the folds and fracture occurred in the vicinity of coal-seams. It emphases the analysis on the relationship between structural deformation and stratal lithologic combination.Based on the statistics of a series of related parameters in stratigraphy and structure,comprehensive analysis and drawing, this method may provide a good means for the quantitative evaluation and prediction of small scale structure in coal mines. 展开更多
关键词 地下矿区 矿井构造 构造预测 煤矿 多维分析 地层分析
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Direct scaling of residual displacements for bilinear and pinching oscillators
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作者 Mohammad Saifullah Vinay K.Gupta 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期129-149,共21页
The estimation of residual displacements in a structure due to an anticipated earthquake event has increasingly become an important component of performance-based earthquake engineering because controlling these displ... The estimation of residual displacements in a structure due to an anticipated earthquake event has increasingly become an important component of performance-based earthquake engineering because controlling these displacements plays an important role in ensuring cost-feasible or cost-effective repairs in a damaged structure after the event.An attempt is made in this study to obtain statistical estimates of constant-ductility residual displacement spectra for bilinear and pinching oscillators with 5%initial damping,directly in terms of easily available seismological,site,and model parameters.None of the available models for the bilinear and pinching oscillators are useful when design spectra for a seismic hazard at a site are not available.The statistical estimates of a residual displacement spectrum are proposed in terms of earthquake magnitude,epicentral distance,site geology parameter,and three model parameters for a given set of ductility demand and a hysteretic energy capacity coefficient in the case of bilinear and pinching models,as well as for a given set of pinching parameters for displacement and strength at the breakpoint in the case of pinching model alone.The proposed scaling model is applicable to horizontal ground motions in the western U.S.for earthquake magnitudes less than 7 or epicentral distances greater than 20 km. 展开更多
关键词 residual displacement spectrum bilinear hysteresis model pinching hysteresis model nonlinear analysis scaling model
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The Research of Change Trend of Our Government's Public Expenditure Scale
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作者 孔祥利 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2004年第S2期441-443,共3页
It is obvious that the change trend of our government expenditure scale declined constantly .The expenditure proportion of science, education, culture and hygiene increased fast, reflected the situation that the finan... It is obvious that the change trend of our government expenditure scale declined constantly .The expenditure proportion of science, education, culture and hygiene increased fast, reflected the situation that the finance of our country was transformed into “public finance” from “building type finance” gradually.The expenditure proportion of the local is higher than central authorities. This is disadvantageous for our country’s economy development and society stability. 展开更多
关键词 PUBLIC EXPENDITURE scale Chinese ECONOMY FINANCE
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A Probe into Economic Regionalization Theory Analysis Framework of Conflicts Between Scale Expansion and Transaction costs
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作者 Deng Xilong 《International Journal of Technology Management》 2014年第6期15-17,共3页
关键词 经济区域 交易成本 区域化 框架 模扩张 地方政府 经济资源 经济增长
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