期刊文献+
共找到10,779篇文章
< 1 2 250 >
每页显示 20 50 100
Mathematical Modelling for a Multi-Product Inventory Routing Problem with Split Delivery
1
作者 Yuling Yeh Chinyao Low 《Journal of Applied Mathematics and Physics》 2017年第9期1607-1612,共6页
In this article, a multi-product inventory routing problem is studied. One-depot and many retailers in a finite time period are considered, and split delivery is allowed as well for the addressed problem. The objectiv... In this article, a multi-product inventory routing problem is studied. One-depot and many retailers in a finite time period are considered, and split delivery is allowed as well for the addressed problem. The objective is to minimize the overall cost including vehicle cost, inventory holding cost and transportation cost while the delivery schedule and the quantity of each product for each retailer have to be decided simultaneously. A mathematical model is presented for solving the addressed optimally and example is illustrated as well. 展开更多
关键词 inventory ROUTING PROBLEM SPLIT Delivery MATHEMATICAL Model
下载PDF
An updated inventory of marine opisthobranch(Mollusca,Gastropoda)from the territorial waters of the Republic of Mauritius
2
作者 Lisa AH SHEE TEE Chandani APPADOO +1 位作者 Daneshwar PUCHOOA Vishwakalyan BHOYROO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期226-243,共18页
Island ecosystems support diverse aquatic invertebrate communities comprising endemic taxa.Documentation of existing species is important for conservation.In this study,a checklist of marine opisthobranch from the Rep... Island ecosystems support diverse aquatic invertebrate communities comprising endemic taxa.Documentation of existing species is important for conservation.In this study,a checklist of marine opisthobranch from the Republic of Mauritius is presented.A combination of benthic surveys(50 m×5 m in triplicates),rover diving techniques and photo documentation were used over two years(2018–2020)within 35 sheltered and unsheltered lagoons.Morphological and molecular analysis were used for identification.Species composition within sheltered and unsheltered areas in Mauritius was estimated using the Bray-Curtis similarity.The checklist featured 117 species belonging to 61 genera and 28families,of which 13 are new records.The findings increased the knowledge of opisthobranch diversity from the Mauritius by 15.4%.Among the listed species,the distribution range of Cyerce nigra,Actinocyclus papillatus,and Phyllidia picta extended from the Western Pacific to the South Western Indian Ocean.Molecular analysis of the undescribed Gymnodoris sp.showed it resembled Gymnodoris sp.from Hawaii and were different by a genetic distance value of 10.6%.The species richness and evenness were higher within the sheltered regions of Mauritius which harboured the food resource of opisthobranch.These areas as compared to unsheltered regions were heavily populated,suggesting the probable influence of wave actions on opisthobranch diversity and abundance.The order Nudibranchia was reported as most speciose,with 86 species.The Sacoglossa and Nudibranchia were observed only on macroalgae and sponges respectively.High abundance was also recorded on shipwrecks which are the most common form of artificial reefs.With the inclusion of observations from previous studies,201species belonging to 94 genera and 36 families are now known from the Mauritius. 展开更多
关键词 marine opisthobranch inventory new record occurrence Republic of Mauritius Indian Ocean
下载PDF
Multi-Objective Optimization of Multi-Product Parallel Disassembly Line Balancing Problem Considering Multi-Skilled Workers Using a Discrete Chemical Reaction Optimization Algorithm
3
作者 Xiwang Guo Liangbo Zhou +4 位作者 Zhiwei Zhang Liang Qi Jiacun Wang Shujin Qin Jinrui Cao 《Computers, Materials & Continua》 SCIE EI 2024年第9期4475-4496,共22页
This work investigates a multi-product parallel disassembly line balancing problem considering multi-skilled workers.A mathematical model for the parallel disassembly line is established to achieve maximized disassemb... This work investigates a multi-product parallel disassembly line balancing problem considering multi-skilled workers.A mathematical model for the parallel disassembly line is established to achieve maximized disassembly profit and minimized workstation cycle time.Based on a product’s AND/OR graph,matrices for task-skill,worker-skill,precedence relationships,and disassembly correlations are developed.A multi-objective discrete chemical reaction optimization algorithm is designed.To enhance solution diversity,improvements are made to four reactions:decomposition,synthesis,intermolecular ineffective collision,and wall invalid collision reaction,completing the evolution of molecular individuals.The established model and improved algorithm are applied to ball pen,flashlight,washing machine,and radio combinations,respectively.Introducing a Collaborative Resource Allocation(CRA)strategy based on a Decomposition-Based Multi-Objective Evolutionary Algorithm,the experimental results are compared with four classical algorithms:MOEA/D,MOEAD-CRA,Non-dominated Sorting Genetic Algorithm Ⅱ(NSGA-Ⅱ),and Non-dominated Sorting Genetic Algorithm Ⅲ(NSGA-Ⅲ).This validates the feasibility and superiority of the proposed algorithm in parallel disassembly production lines. 展开更多
关键词 Parallel disassembly line balancing problem multi-product multiskilled workers discrete chemical reaction optimization algorithm
下载PDF
Intelligent Decision-Making in Warehouse Management: How AI Automation Improves Inventory Tracking, Order Fulfillment, and Logistics Efficiency Compared to Drone Technology
4
作者 Somil Nishar 《Intelligent Control and Automation》 2024年第1期1-8,共8页
This paper analyzes how artificial intelligence (AI) automation can improve warehouse management compared to emerging technologies like drone usage. Specifically, we evaluate AI’s impact on crucial warehouse function... This paper analyzes how artificial intelligence (AI) automation can improve warehouse management compared to emerging technologies like drone usage. Specifically, we evaluate AI’s impact on crucial warehouse functions—inventory tracking, order fulfillment, and logistics efficiency. Our findings indicate AI automation enables real-time inventory visibility, optimized picking routes, and dynamic delivery scheduling, which drones cannot match. AI better leverages data insights for intelligent decision-making across warehouse operations, supporting improved productivity and lower operating costs. 展开更多
关键词 Warehouse Management Artificial Intelligence AUTOMATION inventory Management Order Fulfillment
下载PDF
A Note on an Order Level Inventory Model with Varying Two-Phased Demand and Time-Proportional Deterioration
5
作者 Sephali Mohanty Trailokyanath Singh +1 位作者 Sudhansu Sekhar Routary Chinmayee Naik 《American Journal of Operations Research》 2024年第1期59-73,共15页
The main purpose of this paper is to generalize the effect of two-phased demand and variable deterioration within the EOQ (Economic Order Quantity) framework. The rate of deterioration is a linear function of time. Th... The main purpose of this paper is to generalize the effect of two-phased demand and variable deterioration within the EOQ (Economic Order Quantity) framework. The rate of deterioration is a linear function of time. The two-phased demand function states the constant function for a certain period and the quadratic function of time for the rest part of the cycle time. No shortages as well as partial backlogging are allowed to occur. The mathematical expressions are derived for determining the optimal cycle time, order quantity and total cost function. An easy-to-use working procedure is provided to calculate the above quantities. A couple of numerical examples are cited to explain the theoretical results and sensitivity analysis of some selected examples is carried out. 展开更多
关键词 Deteriorating Items EOQ (Economic Order Quantity) inventory Time-Proportional Deterioration Two-Phased Demand
下载PDF
An open-accessed inventory of landslides triggered by the M_(S)6.8 Luding earthquake,China on September 5,2022 被引量:3
6
作者 Yuandong Huang Chenchen Xie +6 位作者 Tao Li Chong Xu Xiangli He Xiaoyi Shao Xiwei Xu Tao Zhan Zhaoning Chen 《Earthquake Research Advances》 CSCD 2023年第1期37-44,共8页
This study constructs a preliminary inventory of landslides triggered by the M_(S) 6.8 Luding earthquake based on field investigation and human-computer interaction visual interpretation on optical satellite images.Th... This study constructs a preliminary inventory of landslides triggered by the M_(S) 6.8 Luding earthquake based on field investigation and human-computer interaction visual interpretation on optical satellite images.The results show that this earthquake triggered at least 5007 landslides,with a total landslide area of 17.36 km^(2),of which the smallest landslide area is 65 m^(2)and the largest landslide area reaches 120747 m^(2),with an average landslide area of about 3500 m^(2).The obtained landslides are concentrated in the IX intensity zone and the northeast side of the seismogenic fault,and the area density and point density of landslides are 13.8%,and 35.73 km^(-2) peaks with 2 km as the search radius.It should be noted that the number of landslides obtained in this paper will be lower than the actual situation because some areas are covered by clouds and there are no available post-earthquake remote sensing images.Based on the available post-earthquake remote sensing images,the number of landslides triggered by this earthquake is roughly estimated to be up to 10000.This study can be used to support further research on the distribution pattern and risk evaluation of the coseismic landslides in the region,and the prevention and control of landslide hazards in the seismic area. 展开更多
关键词 Luding earthquake Landslide inventory Coseismic landslides Visual interpretation Field investigation
下载PDF
Spatial distribution and inventory of natural gas hydrate in the Qiongdongnan Basin,northern South China Sea 被引量:1
7
作者 Zhongxian ZHAO Ning QIU +4 位作者 Zhen SUN Wen YAN Genyuan LONG Pengchun LI Haiteng ZHUO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第2期729-739,共11页
Natural gas hydrate is a potential clean energy source and is related to submarine geohazard,climate change,and global carbon cycle.Multidisciplinary investigations have revealed the occurrence of hydrate in the Qiong... Natural gas hydrate is a potential clean energy source and is related to submarine geohazard,climate change,and global carbon cycle.Multidisciplinary investigations have revealed the occurrence of hydrate in the Qiongdongnan Basin,northern South China Sea.However,the spatial distribution,controlling factors,and favorable areas are not well defined.Here we use the available high-resolution seismic lines,well logging,and heat flow data to explore the issues by calculating the thickness of gas hydrate stability zone(GHSZ)and estimating the inventory.Results show that the GHSZ thickness ranges between mostly~200 and 400 m at water depths>500 m.The gas hydrate inventory is~6.5×109-t carbon over an area of~6×104 km2.Three areas including the lower uplift to the south of the Lingshui sub-basin,the Songnan and Baodao sub-basins,and the Changchang sub-basin have a thick GHSZ of~250-310 m,250-330 m,and 350-400 m,respectively,where water depths are~1000-1600 m,1000-2000 m,and2400-3000 m,respectively.In these deep waters,bottom water temperatures vary slightly from~4 to 2℃.However,heat flow increases significantly with water depth and reaches the highest value of~80-100 mW/m2 in the deepest water area of Changchang sub-basin.High heat flow tends to reduce GHSZ thickness,but the thickest GHSZ still occurs in the Changchang sub-basin,highlighting the role of water depth in controlling GHSZ.The lower uplift to the south of the Lingshui sub-basin has high deposition rate(~270-830 m/Ma in 1.8-0 Ma);the thick Cenozoic sediment,rich biogenic and thermogenic gas supplies,and excellent transport systems(faults,diapirs,and gas chimneys)enables it a promising area of hydrate accumulation,from which hydrate-related bottom simulating reflectors,gas chimneys,and active cold seeps were widely revealed. 展开更多
关键词 gas hydrate stability zone gas hydrate inventory Qiongdongnan Basin South China Sea
下载PDF
Inventory of Host Plants and Parasitoids of the Fall Armyworm (FAW), Spodoptera frugiperda (JE Smith), in the Southern Agricultural Zone of Niger
8
作者 Ousmane Zakari Moussa Souleymane Laminou +2 位作者 Hamissou Zangui Laouali Amadou Ibrahim Baoua Boukari 《Journal of Agricultural Chemistry and Environment》 CAS 2023年第1期16-27,共12页
The fall armyworm, Spodoptera frugiperda (JE Smith), is a polyphagous pest reported in sub-Saharan Africa since 2016 and has expanded rapidly in almost Africa. In Niger, Spodoptera frugiperda (JE Smith) is considered ... The fall armyworm, Spodoptera frugiperda (JE Smith), is a polyphagous pest reported in sub-Saharan Africa since 2016 and has expanded rapidly in almost Africa. In Niger, Spodoptera frugiperda (JE Smith) is considered like a major pest of maize, to which it causes significant damage, in a context where proven control methods against this moth remain almost non-existent. The objective of the present study was to determine the economic importance of FAW through the damage caused to the different host plants and to identify the parasitoids of this caterpillar. The study was conducted in the southern agricultural zone of Niger, specifically in the regions of Dosso, Maradi, Tahoua and Zinder. FAW eggs and caterpillars were collected from six villages in each region and then incubated and reared in the entomology laboratory of INRAN in Maradi. The rate of infestation of the different crops by FAW was determined as well as the observation of the beneficiaries. The results obtained indicate the presence of FAW on millet with an attack rate varying from 45.7% to 68%, sorghum with 47.2% to 62.25% and sesame with 9.7%. This work also revealed an oophagous parasitoid, Telenomus remus with 138 ± 23 and larval parasitoids, Cotesia sp with 16 ± 1 maximum number of individuals emerged from the collected material. Also, it was identified the parasitoid Cotesia icipe with a rate of parasitism from 4.6% to 5.75%;the Charops ater whose rate of parasitism varies from 4.5% and 12.25% but for Chelonus insularis with 17.25% and Tachnidae with 53%. These very interesting results will constitute a basis for the development of biological control and a component of an agroecological management strategy of caterpillar. 展开更多
关键词 inventory Host Plants Spodoptera frugiperda PARASITOIDS NIGER
下载PDF
Screening Tree Species for Carbon Storage Potential through Urban Tree Inventory in Planted Vegetation
9
作者 Abdullah Sulaiman Al-Nadabi Hameed Sulaiman 《Open Journal of Forestry》 2023年第1期61-74,共14页
Urban tree inventory is a great tool for gathering data that can be used by different end users. This study attempted to chart the species diversity in planted areas and measure their tree diameter at breast height to... Urban tree inventory is a great tool for gathering data that can be used by different end users. This study attempted to chart the species diversity in planted areas and measure their tree diameter at breast height to screen them for the carbon storage potential. A total of 2860 trees belonging to 36 species were recorded in the planted vegetation in parks and avenue plantation. The dominant species were Azadirachta indicia (25.5%), Conocarpus erectus (19.2%), Ficus spp. (15.5%), Tabebuia rosea (9.2%), Peitophorum pterocarpum (9.0%) and the remaining represents (21.6%) of the tree identified in this study. It was found that the highest contribution of carbon sequestration (CO<sub>2</sub> equivalent) is dominated by the Ficus spp. (30.3%) with a total of 3399.3 tCO<sub>2</sub>eq, followed by Azadirachta indicia (25.4%) with a total of 2845.2 tCO<sub>2</sub>eq and Conocarpus erectus (20.4%) with a total of 2286 tCO<sub>2</sub>eq. The entire area has the capability to sequester around 11,213.3 tCO<sub>2</sub>eq and on average of 3.9 ± 0.1 tCO<sub>2</sub>eq. In accordance with the findings, it is imperative for the preservation of a sustainable environment to have vegetation that has the capacity to store carbon. The study suggests, there is potential to increase carbon sequestration in urban cities through plantation programs on existing and new land uses and along roads. 展开更多
关键词 Tree inventory Urban Vegetation Carbon Storage Carbon Sequestration SCREENING
下载PDF
Inventory of the Thermo-Physiological Behavior of Fabrics—A Review
10
作者 Nicole Mölders 《Journal of Textile Science and Technology》 2023年第2期127-150,共24页
A comprehensive literature review was performed to create an inventory of thermal-physiological quantities for fabrics from different fiber materials, material blends, and fabric structures. The goal was to derive ove... A comprehensive literature review was performed to create an inventory of thermal-physiological quantities for fabrics from different fiber materials, material blends, and fabric structures. The goal was to derive over-arching concepts that cannot be seen by the individual studies alone. Equations of best fits suggest non-linear changes for fabric thickness, thermal and water-vapor resistance with changes in material blend ratio. Air permeability decreases with increasing fabric density and fabric weight wherein the degree of decrease differs among fabric materials, blend ratio, and fabric structure. Water-vapor transmission rates strongly depend on fabric thickness, material, and blend, but marginally depend on fabric structure as long as the fabric and material thickness remain the same. 展开更多
关键词 Thermal Resistance of Fabrics Thermal Conductivity of Fabrics Water-Vapor Resistance of Fabrics Water-Vapor Transmission Rate inventory of Thermal-Physiological Characteristics of Fabrics Energetics of Fabrics
下载PDF
基于零库存目标的体外诊断试剂供应链质量评价与改进研究 被引量:1
11
作者 吴函 徐智勇 +4 位作者 高小坤 葛文俊 马宪礼 丁蔚 李伟政 《中国医学装备》 2024年第2期127-131,161,共6页
目的:制定体外诊断试剂供应链的零库存管理目标,评价供应链质量,改进试剂供应中存在的问题。方法:从体外诊断试剂的库存量、供应效率和产品质量方面分析体外诊断试剂管理中存在的问题,制定医院运营、管理质量和患者利益最优化的管理体系... 目的:制定体外诊断试剂供应链的零库存管理目标,评价供应链质量,改进试剂供应中存在的问题。方法:从体外诊断试剂的库存量、供应效率和产品质量方面分析体外诊断试剂管理中存在的问题,制定医院运营、管理质量和患者利益最优化的管理体系,构建零库存管理路径和质量评价模型。选取2020年1月至2023年3月江苏省苏北人民医院采购的21种类型85个型号的体外诊断试剂,根据供应链质量管理方式不同,分别采用按需库存管理模式(模式1)和零库存管理模式(模式2),对比两种管理模式的需求采购、库存管理和临床使用效果。结果:采用模式2管理方式的体外诊断试剂的采购需求达标率、供应能力优质率和临床使用匹配度分别为(93.35±3.62)%、(94.87±2.63)%和(96.08±2.31)%,均高于模式1,其差异有统计学意义(Z=2.489、2.836、2.838,P<0.05),存产品长期积压、环境不达标和信息不及时的例数分别为(2.92±2.54)例、(2.83±1.59)例和(5.58±3.12)例,均低于模式1,其差异有统计学意义(Z=2.959、3.037、3.703,P<0.05);临床科室、医技科室及采购中心对模式2的体外诊断试剂的供应配送和信息沟通的满意度分别为97.8%和93.3%、97.0%和87.9%、100%和84.6%,均高于模式1,其差异有统计学意义(χ^(2)_(临床科室)=5.428、6.133,χ^(2)_(医技科室)=3.958、3.937,χ^(2)_(采购中心)=5.159、4.996,P<0.05)。结论:零库存管理模式能够提高体外诊断试剂需求采购的规范性,降低库存管理中积压失效问题的发生率,提升临床供应服务质量。 展开更多
关键词 零库存管理 体外诊断试剂 供应链 招标采购 库房管理
下载PDF
城市存量土地更新的动力机制研究 被引量:1
12
作者 阳建强 孙丽萍 朱雨溪 《西部人居环境学刊》 CSCD 北大核心 2024年第1期1-7,共7页
随着城市化的加速发展,城市面临着空间资源有限、环境压力不断加大的问题。城市存量土地更新成为优化城市发展格局、提高资源利用效率的重要手段。论文阐述了城市存量土地的内涵,分析了城市存量土地类型与基本特征,构建了“权力—资本... 随着城市化的加速发展,城市面临着空间资源有限、环境压力不断加大的问题。城市存量土地更新成为优化城市发展格局、提高资源利用效率的重要手段。论文阐述了城市存量土地的内涵,分析了城市存量土地类型与基本特征,构建了“权力—资本—民生”三大驱动力交互作用影响的更新动力分析框架,重点分析讨论了居住类存量土地的“政府+社会”协作更新机制、产业类存量土地的“政府+市场”协作更新机制、公共设施类存量土地的政府主导更新机制、公共空间类存量土地的政府主导更新机制以及历史文化类存量土地的多方协作更新机制等五种更新驱动作用机制,以期为城市存量土地更新制度设计与治理优化路径制定提供依据,更好地推动城市更新的协同、健康与可持续发展。 展开更多
关键词 存量土地 城市更新 更新动力 动力机制 制度建设
下载PDF
我国垃圾填埋碳排放核算标准的编制建议
13
作者 何品晶 李晓静 +3 位作者 吕凡 仇俊杰 廖南林 章骅 《中国工程科学》 CSCD 北大核心 2024年第2期174-184,共11页
填埋作为我国主要的垃圾处理方式之一,是碳排放的重要来源;编制我国垃圾填埋碳排放核算标准,将支持碳排放统计核算体系建设,推进碳达峰、碳中和目标进程。本文梳理了国内外垃圾填埋碳排放核算的相关标准和指南研制进展,分析了我国垃圾... 填埋作为我国主要的垃圾处理方式之一,是碳排放的重要来源;编制我国垃圾填埋碳排放核算标准,将支持碳排放统计核算体系建设,推进碳达峰、碳中和目标进程。本文梳理了国内外垃圾填埋碳排放核算的相关标准和指南研制进展,分析了我国垃圾填埋碳排放核算标准编制面临的挑战,在深入讨论相关标准的基准方法、编制重点任务的基础上提出了有关发展建议。研究认为,国际上已有的标准和指南以及提供的缺省值不完全适用于我国垃圾填埋碳排放核算的实际情况,目前我国缺少规范统一的垃圾填埋碳排放核算方法,也缺乏可靠的核算清单数据。为此,针对我国填埋垃圾特征和技术现状,提出了我国垃圾填埋碳排放核算方法、核算范围和清单的建议内容;明晰了我国垃圾填埋碳排放核算标准编制的重点任务,提供了适合我国垃圾填埋场景的清单数据获取方式。后续,可充分考虑地区因素,采用我国特征性数据,以获得更贴合实际情况的垃圾填埋碳排放核算结果,据此开展我国垃圾填埋碳排放核算标准的编制工作。 展开更多
关键词 垃圾填埋 碳排放 标准 核算方法 清单数据
下载PDF
老年抑郁问卷在心力衰竭患者中的应用性评估
14
作者 梁玉兰 吕晓珍 +5 位作者 崔飞环 王雪梅 吕强 蔡松 宁新惠 王华丽 《心肺血管病杂志》 CAS 2024年第5期474-477,498,共5页
目的:评估老年抑郁问卷(geriatric depression inventory,GDI)在老年心力衰竭患者中进行抑郁障碍筛查的价值,确定最佳划界分。方法:采用方便抽样法,选取2017年9月至2018年12月期间,在北京市三家综合医院就诊的老年心力衰竭患者,共195例... 目的:评估老年抑郁问卷(geriatric depression inventory,GDI)在老年心力衰竭患者中进行抑郁障碍筛查的价值,确定最佳划界分。方法:采用方便抽样法,选取2017年9月至2018年12月期间,在北京市三家综合医院就诊的老年心力衰竭患者,共195例接受了GDI评估。以中文版简明国际神经精神访谈(mini-international neuropsychiatric interview,M.I.N.I.)为“金标准”。结果:根据M.I.N.I.结果,受试者被分为抑郁障碍组(共90例,其中包括52例重性抑郁障碍,30例轻性抑郁障碍,8例心境恶劣)和非抑郁障碍组(105例)。GDI的ROC曲线下面积为0.98(SE=0.01,95%CI:0.97~1.00,P<0.01)。最佳划界分为5分,此时灵敏度和特异度均为93.3%,阳性预测值和阴性预测值分别为94.5%和94.2%。结论:GDI在老年心力衰竭人群进行抑郁障碍筛查时筛查价值高,可在该人群中进行推广,最佳划界分为5分。 展开更多
关键词 老年抑郁问卷 抑郁 心力衰竭 心理学试验
下载PDF
人工耳蜗植入对成人语后聋患者植入侧耳鸣的影响
15
作者 李玲 王乐 +3 位作者 户红艳 李红敏 李盼盼 叶放蕾 《听力学及言语疾病杂志》 CAS CSCD 北大核心 2024年第2期138-141,共4页
目的 探究成人语后聋患者人工耳蜗植入术后植入侧耳鸣的变化,并分析其影响因素。方法 2017年1月~2021年12月于郑州大学第一附属医院耳科进行单侧人工耳蜗植入的47例成人语后聋伴耳鸣患者,分别于术前和术后开机6个月进行耳鸣问卷评估,评... 目的 探究成人语后聋患者人工耳蜗植入术后植入侧耳鸣的变化,并分析其影响因素。方法 2017年1月~2021年12月于郑州大学第一附属医院耳科进行单侧人工耳蜗植入的47例成人语后聋伴耳鸣患者,分别于术前和术后开机6个月进行耳鸣问卷评估,评估材料为耳鸣障碍量表(tinnitus handicap inventory,THI)和视觉模拟量表(visual analogue scale,VAS),比较人工耳蜗植入术后患者耳鸣的变化,并分析其可能的影响因素。结果 47例患者人工耳蜗植入术前、术后开机6个月时THI评分别为36.94±13.337、14.48±12.726分,VAS评分分别为5.13±1.676、2.34±1.903分,术后评分均较术前降低,差异均有统计学意义(P<0.05);其中18例患者耳鸣完全消失,13例患者耳鸣减轻,14例患者耳鸣无变化,2例患者耳鸣加重,总体耳鸣有效率为66.0%(31/47);术前耳鸣病程与耳鸣严重程度对术后耳鸣预后有影响(P<0.05),术前耳鸣病程≤5年、中度及以上耳鸣组耳鸣有效率分别高于耳鸣病程>5年(P<0.05)、轻微及轻度耳鸣组(P<0.001)。结论 人工耳蜗植入对成年语后聋患者植入侧耳鸣具有抑制作用;术前耳鸣病程短、耳鸣程度重的患者术后耳鸣改善的可能性更大。 展开更多
关键词 人工耳蜗植入 耳鸣 耳鸣障碍量表 视觉模拟量表
下载PDF
镍闪速炉熔炼共生产品生命周期评价碳排放分配问题
16
作者 崔素萍 张端 +3 位作者 孙博学 孟令钦 杨兆宁 聂祚仁 《北京工业大学学报》 CAS CSCD 北大核心 2024年第10期1170-1178,共9页
金属镍生产是典型的多元素共生冶炼过程,清单分配问题是制约其生命周期评价准确性的重要技术因素。以共生反应最为密集的硫化镍矿闪速炉熔炼流程为研究对象,采取边界扩展、物理关联、质量分配等多种清单分配方法,在Ni、Cu、S这3种元素... 金属镍生产是典型的多元素共生冶炼过程,清单分配问题是制约其生命周期评价准确性的重要技术因素。以共生反应最为密集的硫化镍矿闪速炉熔炼流程为研究对象,采取边界扩展、物理关联、质量分配等多种清单分配方法,在Ni、Cu、S这3种元素之间进行CO_2排放分配。边界扩展分配计算结果显示,非金属共生元素与金属产物之间的分配结果为29.86%,金属共生元素之间的分配结果为70.14%。对比分析结果显示,边界扩展方法对于中间态产物的适用性较差;物理关联分配结果准确,但需要大量流程工艺参数支撑;质量分配易于计算,但其准确性取决于共生产品之间的物理化学属性差异。 展开更多
关键词 生命周期评价 碳排放 清单分配 冶金 金属共生
下载PDF
基于森林资源清查资料的盈江县森林生物量和生长量分析
17
作者 汤明华 刘娟 +3 位作者 高林 赵金发 樊骥善 余涛 《西部林业科学》 CAS 北大核心 2024年第1期129-137,共9页
为确定盈江县森林碳储量和碳汇潜力的变化特征及其影响因子,以便更好地分析盈江县森林生物量和生长量。基于盈江县2012年和2017年森林资源清查数据,利用生物量换算因子连续函数法和异速生长方程,评估盈江县森林碳储量和碳汇潜力的变化... 为确定盈江县森林碳储量和碳汇潜力的变化特征及其影响因子,以便更好地分析盈江县森林生物量和生长量。基于盈江县2012年和2017年森林资源清查数据,利用生物量换算因子连续函数法和异速生长方程,评估盈江县森林碳储量和碳汇潜力的变化特征及其影响因子。结果显示:(1)盈江县森林生物量储量丰富,达85.55 t/hm^(2)。其中:栎类林最大,为168.3 t/hm^(2);核桃林最低,为7.10 t/hm^(2)。(2)不同林龄林分生物量差异较大,近熟林最高,其次分别为中龄林、成熟林、过熟林、幼龄林。(3)常绿阔叶林的林分生长量最大,其次是落叶阔叶林和针叶林。结果表明:盈江县森林生物量储量丰富且以阔叶林为主;林龄和年均气温是影响林分生长和生物量的主要因素。 展开更多
关键词 森林资源清查 生物量评估 生长量 影响因子 随机森林模型
下载PDF
基于EOQ模型传统涉外制造企业物料库存管理研究
18
作者 钟飞燕 《物流科技》 2024年第11期39-42,共4页
库存成本管理水平高低对企业经营成本有着直接影响,提高库存管理水平,有助于降低库存成本和经营成本。文章基于EOQ模型,以传统涉外制造企业DJ公司为例,选取物料面浆作为研究对象,通过对EOQ模型使用前后库存成本对比分析,发现采用EOQ模型... 库存成本管理水平高低对企业经营成本有着直接影响,提高库存管理水平,有助于降低库存成本和经营成本。文章基于EOQ模型,以传统涉外制造企业DJ公司为例,选取物料面浆作为研究对象,通过对EOQ模型使用前后库存成本对比分析,发现采用EOQ模型后,面浆的库存量和库存总成本比原来有所降低。研究表明,科学合理采用EOQ模型有助于实现订货成本与维持成本最小化,降低企业经营成本,促进企业可持续发展。 展开更多
关键词 库存管理 库存成本 EOQ模型 库存控制模型
下载PDF
中国上市公司存货投资粘性研究
19
作者 张亮亮 黄诗梦 柴紫谦 《管理学报》 北大核心 2024年第2期278-286,316,共10页
以2007~2020年中国沪深A股制造业上市公司为样本,实证研究企业存货投资的粘性行为。研究发现,企业销售收入下降时存货投资减少的幅度小于等量销售收入上升时存货投资增加的幅度,即企业存货投资存在粘性。考虑不同类别存货的差异后发现,... 以2007~2020年中国沪深A股制造业上市公司为样本,实证研究企业存货投资的粘性行为。研究发现,企业销售收入下降时存货投资减少的幅度小于等量销售收入上升时存货投资增加的幅度,即企业存货投资存在粘性。考虑不同类别存货的差异后发现,产成品的存货投资粘性更强。进一步,管理者对未来需求的乐观预期、稳定的市场需求和较高的缺货成本是存货投资粘性的重要成因。研究还发现,存货投资粘性越强,企业未来销售收入增长越快,市场竞争力越强,分析师销售收入预测也越乐观和准确,这表明存货投资粘性有助于提升企业产品市场的表现,同时能够向资本市场参与者提供有用的信息,具有一定的信息含量。 展开更多
关键词 存货投资 投资粘性 市场表现 分析师预测
下载PDF
部分共享下航空企业周转件两级库存配置研究
20
作者 付维方 王馨平 张兆民 《航空计算技术》 2024年第1期32-36,共5页
针对周转件的部分共享两级配置问题,将部分共享与库存配置模型相结合,提出了部分共享下周转件两级库存配置模型。企业组建本地级和共享级进行优先级保障,并构建部分共享转运流程。通过马尔可夫分析两级的需求关系和在库库存的状态转移,... 针对周转件的部分共享两级配置问题,将部分共享与库存配置模型相结合,提出了部分共享下周转件两级库存配置模型。企业组建本地级和共享级进行优先级保障,并构建部分共享转运流程。通过马尔可夫分析两级的需求关系和在库库存的状态转移,建立了基于稳态概率的两级库存转运模型。在此模型基础上,结合备件保障成本构成分析,建立以服务水平为约束的部分共享转运成本模型。运用粒子群算法求解部分共享模型下的两级库存配置和系统总成本。通过算例计算,将得到的结果与相同保障率下的独立保障模型进行对比,表明部分共享的两级配置模型能够使系统总成本和库存量显著减少,为制定合理的备件配置方案提供决策依据。 展开更多
关键词 两级库存 部分共享 周转件 马尔可夫 库存配置
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部