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Evaluation of the Performance of Financial Support for Agriculture in Guizhou Province Using Secondary Relative Benefit Model Based on DEA
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作者 HUANG Qing-hua NIU Lei +1 位作者 WEI Xiao-ya XIE Lin-sha 《Asian Agricultural Research》 2012年第6期1-4,共4页
We use the secondary relative benefit model based on DEA to evaluate the performance of agricultural financial expenditure in Guizhou Province, which can give due consideration to the production effectiveness determin... We use the secondary relative benefit model based on DEA to evaluate the performance of agricultural financial expenditure in Guizhou Province, which can give due consideration to the production effectiveness determined by objective natural conditions, and management effectiveness of all regions (as decision-making body) in the use of financial fund for supporting agriculture. In general, there is north-south gradient difference in the performance of financial support for agriculture between regions in Guizhou Province. The drought in 2010 has significant impact on the technical efficiency in the whole province; the performance score of each item in Liupanshui City and Southwest Guizhou is very low; the technical efficiency and management efficiency in most regions need to be improved. In order to improve the performance of financial support for agriculture, we need to ensure the scale of input; at the same time, provide appropriate preferential financial policies for agricultural infrastructure, especially the construction of rural water conservancy, development and promotion of agricultural science and technology, and other fields; adopt the way of special check and acceptance of supporting projects to strengthen the use management of the fund for agriculture. 展开更多
关键词 FINANCIAL support for AGRICULTURE PERFORMANCE eval
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Study on Soil and Water Conservation Benefit Models of Grassland Ecosystem──A Case Study on Jianou Mountain Grasslan Ecosystem
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作者 ZHU Lian-qi, WANG Yu-biao, ZHAO Qing-liang 1. College of Environment and Planning, Henan University, Kaifeng 475001, China 2. Zhoukou Institute of Environment Science, Zhoukou 466001, China 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2001年第4期392-396,共5页
This paper studies the mechanism of grassland ecosystem's soil and water conservation function on the basis of two years experiment and inspection in Jianou mountain grassland ecosystem experiment station, Fujian ... This paper studies the mechanism of grassland ecosystem's soil and water conservation function on the basis of two years experiment and inspection in Jianou mountain grassland ecosystem experiment station, Fujian province. After anaIysis on the data of soil erosion and runoff coefficient, relations between eroded soil, runoff and slope gradient. we establish soil and water conservation benefit models. According to the mode1s, experiment and inspection results, some proposals have been made to decrease the area of soil erosion in Fujian mountainous areas, e. g., optimizing land use structure in mountainous areas, taking suitable measures for local condition, closing hills for grassland development, accelerating restoration and raising quality of mountain grassland ecosystem, strengthening scientific and technological input, breeding the grass species that are suitable to local physical geographic condition. 展开更多
关键词 soil and water conservation benefit models grassland ecosystem land use structure
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Spatial distribution prediction and benefits assessment of green manure in the Pinggu District,Beijing,based on the CLUE-S model 被引量:14
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作者 ZHANG Li-ping ZHANG Shi-wen +3 位作者 ZHOU Zhi-ming HOU Sen HUANG Yuan-fang CAO Wei-dong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第2期465-474,共10页
Green manure use in China has declined rapidly since the 1980 s with the extensive use of chemical fertilizers.The deterioration of field environments and the demand for green agricultural products have resulted in mo... Green manure use in China has declined rapidly since the 1980 s with the extensive use of chemical fertilizers.The deterioration of field environments and the demand for green agricultural products have resulted in more attention to green manure.Human intervention and policy-oriented behaviors likely have large impacts on promoting green manure planting.However,little information is available regarding on where,at what rates,and in which ways(i.e.,intercropping green manure in orchards or rotating green manure in cropland) to develop green manure and what benefits could be gained by incorporating green manure in fields at the county scale.This paper presents the conversion of land use and its effects at small region extent(CLUE-S) model,which is specifically developed for the simulation of land use changes originally,to predict spatial distribution of green manure in cropland and orchards in 2020 in Pinggu District located in Beijing,China.Four types of land use for planting or not planting green manure were classified and the future land use dynamics(mainly croplands and orchards) were considered in the prediction.Two scenarios were used to predict the spatial distribution of green manure based on data from 2011:The promotion of green manure planting in orchards(scenario 1) and the promotion of simultaneous green manure planting in orchards and croplands(scenario 2).The predictions were generally accurate based on the receiver operating characteristic(ROC) and Kappa indices,which validated the effectiveness of the CLUE-S model in the prediction.In addition,the spatial distribution of the green manure was acquired,which indicated that green manure mainly located in the orchards of the middle and southern regions of Dahuashan,the western and southern regions of Wangxinzhuang,the middle region of Shandongzhuang,the eastern region of Pinggu and the middle region of Xiagezhuang under scenario 1.Green manure planting under scenario 2 occurred in orchards in the middle region of Wangxinzhuang,and croplands in most regions of Daxingzhuang,southern Pinggu,northern Xiagezhuang and most of Mafang.The spatially explicit results allowed for the assessment of the benefits of these changes based on different economic and ecological indicators.The economic and ecological gains of scenarios 1 and 2 were 175691 900 and143000 300 CNY,respectively,which indicated that the first scenario was more beneficial for promoting the same area of green manure.These results can facilitate policies of promoting green manure and guide the extensive use of green manure in local agricultural production in suitable ways. 展开更多
关键词 CLUE-S model green manure spatial distribution prediction benefits assessment
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A Cost-benefit Measuring Model of Green Products in Manufacturing Industry 被引量:1
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作者 Qingshan Zhang Luping Zhang 《Chinese Business Review》 2005年第5期8-15,共8页
The paper builds up a cost-benefit measuring model of green products in manufacturing industry throughout its full life cycle, which can quantify green products' cost and benefit completely and correctly under the ci... The paper builds up a cost-benefit measuring model of green products in manufacturing industry throughout its full life cycle, which can quantify green products' cost and benefit completely and correctly under the circumstance of satisfying enterprise, customer, environment and society. It also puts forth an operable method to estimate social benefit by opportunity cost and establishes a profit maximization-programming model. The model can be applied to justify whether some kinds of green products should be developed and produced. 展开更多
关键词 green product full life cycle social benefit estimation the measuring model
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Cost-Benefit Assessment of Inspection and Repair Planning for Ship Structures Considering Corrosion Model Uncertainty
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作者 李典庆 唐文勇 张圣坤 《China Ocean Engineering》 SCIE EI 2005年第3期409-420,共12页
Owing to high costs and unnecessary inspections necessitated by the traditional inspection planning for ship structures, the risk-based inspection and repair planning should be investigated for the most cost-effective... Owing to high costs and unnecessary inspections necessitated by the traditional inspection planning for ship structures, the risk-based inspection and repair planning should be investigated for the most cost-effective inspection. This paper aims to propose a cost-benefit assessment model of risk-based inspection and repair planning for ship structures subjected to corrosion deterioration. Then, the benefit-cost ratio is taken to be an index for the selection of the optimal inspection and repair strategy. The planning problem is formulated as an optimization problem where the benefit-cost ratio for the expected lifetime is maximized with a constraint on the minimum acceptalbe reliability index. To account for the effect of corrosion model uncertainty on the cost-benefit assessment, two corrosion models, namgly, Paik' s model and Guedes Soares' model, are adopted for analysis. A numerical example is presented to illustrate the proposed method. Sensitivity studies are also providet. The results indicate that the proposed method of risk-based cost-benefit analysis can effectively integrate the economy with reliability of the inspection and repair planning. A balance can be achieved between the risk cost and total expected inspection and repair costs with the proposed method, which is very. effective in selecting the optimal inspection and repair strategy. It is pointed out that the corrosion model uncertainty and parametric uncertaintg have a significant impact on the cost-benefit assessment of inspection and repair planning. 展开更多
关键词 ship structures inspection and repair planning COST-benefit model uncertainty
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西藏草业时空拓展的模式和路径 被引量:1
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作者 余成群 庞晓攀 +1 位作者 李捷 钟志明 《草业科学》 CAS CSCD 北大核心 2024年第5期1255-1265,共11页
草业发展是维护西藏生态屏障安全的重要内容,也是高原特色畜牧业高质量发展和西藏牧民维持生计的传统优势产业。国家生态安全与粮食安全战略背景下,西藏草业高质量发展受到时空条件的制约。本研究借助城市时空拓展理论,阐明了西藏草业... 草业发展是维护西藏生态屏障安全的重要内容,也是高原特色畜牧业高质量发展和西藏牧民维持生计的传统优势产业。国家生态安全与粮食安全战略背景下,西藏草业高质量发展受到时空条件的制约。本研究借助城市时空拓展理论,阐明了西藏草业发展时空拓展的必要性和可行性,并依据西藏草业资源的禀赋特征,提出了聚焦生态效益模式、生产效益模式、生态和生产效益兼顾模式,以及实现3种模式的路径,以期为西藏草业未来的发展提供理论指导,也为我国其他地区草业时空拓展提供借鉴。 展开更多
关键词 草业多维性 生态效益模式 生产效益模式 生态和生产效益兼顾模式 时空拓展路径
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Comprehensive benefits assessment of the ecological management model in Hobq Desert of China
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作者 Rui Wang Li Hua Zhou Yong Chen 《Research in Cold and Arid Regions》 CSCD 2018年第3期251-260,共10页
The Hobq Desert is the seventh largest desert in China. Since 1988, the effects of ecological management in Hobq Desert have been obvious and a typical desertification control model developed gradually, which is well ... The Hobq Desert is the seventh largest desert in China. Since 1988, the effects of ecological management in Hobq Desert have been obvious and a typical desertification control model developed gradually, which is well known as the "Hobq model". It is important to evaluate the comprehensive benefits of the "Hobq model", but this has not been addressed in previous studies. Thus, we established an index system to comprehensively evaluate the benefits of the "Hobq model", using an analytic hierarchy process method from 1988 to 2013. The results show the following: ecological benefits of the "Hobq model" had a positive trend, but with fluctuations during 2008 and 2009; economic benefits increased by 74% and the maximum value occurred in 2013; and social benefits increased steadily, but with fluctuations in 2010 and 2011. The social benefits were higher than ecological and economic benefits in the same period. Trends in overall benefits of the "Hobq model" were similar to changes in ecological benefits, which increased each year. 展开更多
关键词 benefit assessment comprehensive benefit ecological management Hobq model
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Cost-benefit Analysis of Scale Pig Breeding in Shandong Province Based on Modified Entropy Weight-TOPSIS Model
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作者 Yuanyuan ZHANG Shimin SUN 《Asian Agricultural Research》 2014年第8期21-25,共5页
According to the relevant statistical data in National Agricultural cost-benefit Data Compilation(2001- 2013),we use the modified entropy weight- TOPSIS model to research the cost-benefit status of scale pig breeding ... According to the relevant statistical data in National Agricultural cost-benefit Data Compilation(2001- 2013),we use the modified entropy weight- TOPSIS model to research the cost-benefit status of scale pig breeding in Shandong Province from the perspective of comparing it with that of the entire country and 9 other main pig producing areas. The results show that compared with the national average,the cost-benefit ratio of small scale pig breeding in Shandong Province is lower,while the cost-benefit ratio of medium scale and large scale pig breeding is significantly improved; the cost-benefit ratio of small scale pig breeding in Shandong Province is basically the same as that in 9 other main pig producing areas,while the cost-benefit ratio of medium scale and large scale pig breeding is higher; the output value of main products and the purchase price of piglet are two major bottlenecks restricting the cost-benefit improvement of scale pig breeding in Shandong Province. 展开更多
关键词 PIG SCALE BREEDING COST-benefit analysis TOPSIS mo
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碳减排“时-空-效-益”统筹理论:IV.收益统筹 被引量:2
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作者 魏一鸣 易琛 +2 位作者 袁潇晨 陈炜明 余碧莹 《北京理工大学学报(社会科学版)》 CSSCI 北大核心 2024年第5期39-49,共11页
面对巨大的气候变化损害以及高额的减排行动成本,如何在多时期、多主体框架下统筹经济发展与减排行动,协同推进发展与减排,成为全球气候治理中的关键议题。作为碳减排“时-空-效-益”统筹理论系列论文的组成部分,构建了收益统筹理论。... 面对巨大的气候变化损害以及高额的减排行动成本,如何在多时期、多主体框架下统筹经济发展与减排行动,协同推进发展与减排,成为全球气候治理中的关键议题。作为碳减排“时-空-效-益”统筹理论系列论文的组成部分,构建了收益统筹理论。该理论在综合集成时间统筹、空间统筹、效率统筹相关理论与方法基础上,以最优经济增长为核心,将碳排放问题引入长期宏观经济分析中,深入探析经济发展与减排行动二者间的复杂关系,构建了经济-气候双向耦合的中国气候变化综合评估模型,并设计了多区跨期优化福利函数,实现发展与减排的统筹。基于碳减排“时-空-效-益”统筹理论,应用中国气候变化综合评估模型C3IAM,明确了未来全球及各区域最优减排路径,并提出了各国及国家内部减排任务分配方案,科学回答了碳减排系统工程的减多少、何时减、谁来减、如何减、何效果等关键问题,为统筹发展与减排提供方法基础。 展开更多
关键词 碳减排 收益统筹 气候经济建模 成本收益分析 跨期优化
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Model of Cost-benefit Flow in Six Green Projects in China
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作者 ZhuYongjie ZhouBoling 《Forestry Studies in China》 CAS 2003年第3期49-53,共5页
From the point of cost-benefit flow and with the Six Green Projects in China as the case and background, it is criticized that the current natural resource and environmental management and the policies in China have s... From the point of cost-benefit flow and with the Six Green Projects in China as the case and background, it is criticized that the current natural resource and environmental management and the policies in China have some problems unsolved since the model of cost-benefit flow is still centralized and mainly in an administrative way in spite of many efforts made theoretically and practically. It is suggested that a new model based on market-oriented economy from the point of cost-benefit flow with Six Green Projects Management and Policies System consist of complete natural reserve (NR). Management system included environmental nature reserves in addition to biodiversity nature reserve, paid using nature resources, an environmental conservation and construction industry and renewable resource production incentive system that turn the direct administration and operation to management and services. The detail figure of the new model of cost-benefit flow is provided and the main points related are discussed in this paper. 展开更多
关键词 Six Green Projects model of cost-benefit flow management and policy frame
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Benefit Analysis of Chemical Fertilizer Input for Staple Grain Production Based on Threshold Panel Data Model
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作者 Tengda ZUO Wan NIE 《Asian Agricultural Research》 2018年第9期1-5,8,共6页
Based on the threshold panel data model,this paper analyzed the nonlinear relationship between chemical fertilizer input and grain output. At the provincial level,from the perspective of average and marginal net benef... Based on the threshold panel data model,this paper analyzed the nonlinear relationship between chemical fertilizer input and grain output. At the provincial level,from the perspective of average and marginal net benefits,it compared the effects of chemical fertilizer input on farmers' income. It reached the conclusion that the chemical fertilizer input efficiency has deviated from the optimal level. Thus,only by increasing the marginal productivity of chemical fertilizers,may it be able to increase farmers' income. 展开更多
关键词 化肥投入 粮食产量 农业 计算方法
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浅论基于实施效益决策的标准化业务模式
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作者 杨天 湛希 《中国标准化》 2024年第11期57-63,共7页
为了进一步提升标准化行业对我国高质量发展的促进作用,本文从标准化原理角度探讨了企业和标准化行业获取标准化效益的案例,总结分析了我国现行标准化业务模式的发展、问题、困境和创新苗头,提出一种基于实施效益决策的标准化业务模式,... 为了进一步提升标准化行业对我国高质量发展的促进作用,本文从标准化原理角度探讨了企业和标准化行业获取标准化效益的案例,总结分析了我国现行标准化业务模式的发展、问题、困境和创新苗头,提出一种基于实施效益决策的标准化业务模式,并初步分析了该业务模式的意义和难点。该业务模式综合了标准化需求分析、标准化范围建立、解决方案统筹与测算、方案优化协调与测算、基于效益规则的标准协定、完整贯标改造、标准实施效益核算和实施范围推广等主要工作环节,供学术交流研讨和业务实践指导。 展开更多
关键词 标准化 模式 效益 实施
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Application of the AERMOD Model to Evaluate the Health Benefits Due to Air Pollution from the Public Transport Sector in Ha Noi, Viet Nam
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作者 Tran Do Bao Trung Doan Quang Tri 《Journal of Geoscience and Environment Protection》 2022年第3期13-33,共21页
Fine particulate matter (PM<sub>2.5</sub>) mainly originates from combustion emissions on-road transportation. Exposure to PM<sub>2.5</sub> could be considered one of the primary causes of dise... Fine particulate matter (PM<sub>2.5</sub>) mainly originates from combustion emissions on-road transportation. Exposure to PM<sub>2.5</sub> could be considered one of the primary causes of diseases such as heart attack, stroke, lung cancer, and chronic respiratory, which made it one of the most important co-benefits when evaluating the impact of GHG mitigation measures. This study quantifies the co-benefit of Ha Noi’s modal shift from private to public means of transport, which are reduced air pollution and extended life expectancy, combining AERMOD model and benefit transfer method. Analytical results show that shifting from motorbike to electric train could be the most beneficial option in term of health co-benefit, compared to the usage of standard buses and BRTs. 展开更多
关键词 AERMOD model Air Pollution Health Co-benefit Ha Noi
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基于绿色建筑全寿命周期的增量成本与收益模型研究
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作者 郑双七 吴群 陈馨怡 《安徽职业技术学院学报》 2024年第2期31-35,共5页
基于绿色建筑全寿命周期理论,以现有绿色建筑评价标准为基础,分析绿色建筑全寿命周期内增量成本与增量收益,构建经济性评价模型,并对某绿色建筑项目进行评估与分析,打破绿色建筑“高消费”的固有模式,推动绿色建筑市场化、普及化,促进... 基于绿色建筑全寿命周期理论,以现有绿色建筑评价标准为基础,分析绿色建筑全寿命周期内增量成本与增量收益,构建经济性评价模型,并对某绿色建筑项目进行评估与分析,打破绿色建筑“高消费”的固有模式,推动绿色建筑市场化、普及化,促进绿色建筑发展,加速低碳经济转型。 展开更多
关键词 绿色建筑 全寿命周期 增量成本与收益 模型 经济性评价
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CEV模型下目标收益型养老金的最优投资和支付策略
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作者 叶传秀 石媛 赵永霞 《曲阜师范大学学报(自然科学版)》 CAS 2024年第2期73-82,共10页
该文研究了目标收益计划下养老金的最优投资策略和支付策略.养老金的支付取决于计划的财务状况,且风险由不同代人分担.养老基金可以投资于无风险资产和风险资产,其中风险资产价格由几何布朗运动模型推广为常方差弹性(CEV)模型来驱动.以... 该文研究了目标收益计划下养老金的最优投资策略和支付策略.养老金的支付取决于计划的财务状况,且风险由不同代人分担.养老基金可以投资于无风险资产和风险资产,其中风险资产价格由几何布朗运动模型推广为常方差弹性(CEV)模型来驱动.以最小化收益风险和福利风险的组合为目标,利用动态规划原理和HJB方程,推导出了最优投资策略和最优福利调整的闭型解.最后,数值实例分析了模型参数对控制问题的影响. 展开更多
关键词 目标收益计划 最优投资 CEV模型 代际风险分担
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“双碳”背景下林纸绿色供应链利益分配优化模型及应用研究 被引量:1
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作者 岳庆如 宋鑫鑫 《现代工业经济和信息化》 2024年第2期36-39,42,共5页
在“双碳”发展背景下,考虑核心竞争能力、主观投入水平、客观贡献程度、生态绩效贡献度、风险承担强度等影响因素,构建优化夏普利值法模型,应用算例并结果分析,从研究结果可知,在林纸绿色供应链发展及利益分配过程中,首先要认识到影响... 在“双碳”发展背景下,考虑核心竞争能力、主观投入水平、客观贡献程度、生态绩效贡献度、风险承担强度等影响因素,构建优化夏普利值法模型,应用算例并结果分析,从研究结果可知,在林纸绿色供应链发展及利益分配过程中,首先要认识到影响因素对林纸绿色供应链的发展及利益分配的重要性。其次,要始终将绿色化贯穿林纸绿色供应链整个发展过程,充分体现林纸绿色供应链发展与“双碳”发展的目标一致性。 展开更多
关键词 “双碳” 林纸绿色供应链 利益分配优化模型 应用
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基于价值链的饲料企业营销模式分析
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作者 范志英 《中国饲料》 北大核心 2024年第6期161-164,共4页
市场对动物源性食品的旺盛需求有效提高了饲料企业的经济效益,这对实现饲料企业的可持续发展具有重要的推动作用。但在复杂多变的市场环境下,饲料产品同质化、产能过剩、需求多元化等现实情况都对饲料企业的市场营销提出了挑战。为了更... 市场对动物源性食品的旺盛需求有效提高了饲料企业的经济效益,这对实现饲料企业的可持续发展具有重要的推动作用。但在复杂多变的市场环境下,饲料产品同质化、产能过剩、需求多元化等现实情况都对饲料企业的市场营销提出了挑战。为了更好地帮助饲料企业创造价值,需要从价值链的角度入手,对饲料企业的营销模式进行分析,力求通过提高产品销量来为饲料企业的可持续发展奠定基础。 展开更多
关键词 价值链 饲料企业 营销模式 经济效益 可持续发展
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创新过程视角下产学研深度融合动态利益分配机制
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作者 郭彬 常哲 王文 《技术与创新管理》 2024年第6期612-623,共12页
为构建产学研深度融合动态利益分配机制,在探讨创新过程演进与利益分配影响因素变化的基础上,将过程阶段思想引入利益分配。首先,构建完全信息条件下的两阶段收益分配的Stackelberg博弈模型,在比较产学研合作、协同创新以及产学研深度... 为构建产学研深度融合动态利益分配机制,在探讨创新过程演进与利益分配影响因素变化的基础上,将过程阶段思想引入利益分配。首先,构建完全信息条件下的两阶段收益分配的Stackelberg博弈模型,在比较产学研合作、协同创新以及产学研深度融合的基础上确定事前两阶段的最优投入、产出以及最优收益分配比例;然后,采用模糊层次分析法、模糊综合评价法和Topsis法构建基于风险分担和实际绩效的收益调整模型进一步调整收益分配比例,确定每个创新主体的最终收益分配比例;最后,通过算例证明:该利益分配机制充分考虑了产学研深度融合的特征、风险分担以及创新主体的实际绩效等因素,规避了传统利益分配平均化问题,大幅提高了创新主体投入产出的有效性以及风险承担能力。研究表明:分配系数随着创新过程演进而变化,以满足创新主体在各个融合阶段的利益需求,可为构建产学研深度融合利益分配机制提供参考。 展开更多
关键词 技术创新 产学研深度融合 STACKELBERG博弈模型 利益分配机制 风险共担
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考虑碳减排收益的高速公路差异化收费定价模型
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作者 王江锋 李秀东 +1 位作者 宋之凡 郭恩懿 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第8期14-22,共9页
高速公路差异化收费可以促进道路领域碳减排,助推“双碳”目标实现。文中将碳减排收益作为高速公路效益的组成部分,基于同时考虑高速公路效益和物流企业成本的目标,构建了基于双层规划的高速公路差异化收费定价模型。首先分析了货车路... 高速公路差异化收费可以促进道路领域碳减排,助推“双碳”目标实现。文中将碳减排收益作为高速公路效益的组成部分,基于同时考虑高速公路效益和物流企业成本的目标,构建了基于双层规划的高速公路差异化收费定价模型。首先分析了货车路径选择因素;然后利用Logit模型构建了基于高速公路差异化收费的转移车流量测算方法和基于转移车流量的碳排放量测算方法,并提出了影子价格下的碳交易定价模型;最后,考虑碳减排效益部分最大化和物流企业成本最小化,提出了差异化收费双层规划模型,同时利用山东省高速公路A和并行国省道的车流量数据进行实例分析。结果表明:通过高速公路差异化收费策略的调整,双层规划模型在保证高速公路管理部门的最优化效益下可实现物流企业成本的最小化;在最优收费费率附近调整收费标准,对高速公路A的效益的影响较小,使得高速公路效益的波动影响低于1.5%,结果表现出良好的收益稳定性;文中所提出的差异化收费双层规划模型可实现高速公路碳减排效益最大化和物流企业成本最小化的目标。 展开更多
关键词 差异化收费 双层规划模型 碳减排收益 最优化 实证分析
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病毒性脑炎217例症状性癫痫发生风险的预测研究 被引量:1
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作者 张少浩 朱勇冬 林麒 《安徽医药》 CAS 2024年第7期1430-1434,共5页
目的分析病毒性脑炎并发症状性癫痫的风险因素,据此构建列线图预测模型。方法回顾性分析2018年2月至2022年5月汕头市中心医院收治的217例病毒性脑炎病人临床资料,抽取70%为建模集(152例),30%为验证集(65例)。根据病人是否合并症状性癫痫... 目的分析病毒性脑炎并发症状性癫痫的风险因素,据此构建列线图预测模型。方法回顾性分析2018年2月至2022年5月汕头市中心医院收治的217例病毒性脑炎病人临床资料,抽取70%为建模集(152例),30%为验证集(65例)。根据病人是否合并症状性癫痫,将建模集进一步分为发生组和未发生组,比较两组病人一般资料,选择差异有统计学意义的指标用逐步向前回归法进行非条件多因素logistic分析病毒性脑炎病人症状性癫痫发生的影响因素,并采用R3.4.3软件包绘制基于多因素分析结果的列线图模型。采用Bootstrap法分别对建模集和验证集进行验证,并绘制受试者操作特征曲线(ROC曲线)和决策曲线(DCA)以评估列线图模型的预测效能和临床净获益率。结果217例病毒性脑炎病人中,共46例病人合并症状性癫痫(21.20%),其中建模集中有32例合并症状性癫痫,验证集中有14例合并症状性癫痫;发生组昏迷、大脑皮质损坏、脑电图重度异常、颅脑核磁共振成像(MRI)有责任病灶、累及颞叶或额叶、脑脊液单纯疱疹病毒(HSV)(+)占比及脑脊液压力均高于未发生组(P<0.05);logistic多元回归分析,昏迷、大脑皮质损坏、脑电图重度异常、颅脑MRI有责任病灶、累及颞叶或额叶、脑脊液压力、脑脊液HSV(+)均是病毒性脑炎合并症状性癫痫的影响因素(P<0.05);经Bootsrap法进行验证,建模集其一致性指数(C-index)为0.833,验证集的C-index则为0.830,校正曲线和标准曲线拟合度较好。建模集ROC曲线下面积(AUC)、灵敏度、特异度分别为0.84[98%CI:(0.78,0.89)]、79.17%、84.04%,验证集则为0.81[98%CI:(0.76,0.86)],83.04%,73.64%,提示模型区分度良好。DCA曲线显示病人根据列线图模型进行风险评估可获得满意的净收益。结论昏迷、大脑皮质损坏、脑电图重度异常、颅脑MRI有责任病灶、累及颞叶或额叶、脑脊液压力、脑脊液HSV(+)均是病毒性脑炎合并症状性癫痫的影响因素,综合上述因素针对病毒性脑炎病人构建的列线图预测模型可以较好地个体化预测症状性癫痫的发生,对临床防治症状性癫痫提供指导。 展开更多
关键词 脑炎 病毒性 症状性癫痫 风险因素 列线图模型 临床获益率
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