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Artificial Intelligence for Maximizing Agricultural Input Use Efficiency: Exploring Nutrient, Water and Weed Management Strategies
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作者 Sumit Sow Shivani Ranjan +8 位作者 Mahmoud F.Seleiman Hiba M.Alkharabsheh Mukesh Kumar Navnit Kumar Smruti Ranjan Padhan Dhirendra Kumar Roy Dibyajyoti Nath Harun Gitari Daniel O.Wasonga 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第7期1569-1598,共30页
Agriculture plays a crucial role in the economy,and there is an increasing global emphasis on automating agri-cultural processes.With the tremendous increase in population,the demand for food and employment has also i... Agriculture plays a crucial role in the economy,and there is an increasing global emphasis on automating agri-cultural processes.With the tremendous increase in population,the demand for food and employment has also increased significantly.Agricultural methods traditionally used to meet these requirements are no longer ade-quate,requiring solutions to issues such as excessive herbicide use and the use of chemical fertilizers.Integration of technologies such as the Internet of Things,wireless communication,machine learning,artificial intelligence(AI),and deep learning shows promise in addressing these challenges.However,there is a lack of comprehensive documentation on the application and potential of AI in improving agricultural input efficiency.To address this gap,a desk research approach was used by utilizing peer-reviewed electronic databases like PubMed,Scopus,Goo-gle Scholar,Web of Science,and Science Direct for relevant articles.Out of 327 initially identified articles,180 were deemed pertinent,focusing primarily on AI’s potential in enhancing yield through better management of nutrients,water,and weeds.Taking into account researchfindings worldwide,we found that AI technologies could assist farmers by providing recommendations on the optimal nutrients to enhance soil quality and deter-mine the best time for irrigation or herbicide application.The present status of AI-driven automation in agricul-ture holds significant promise for optimizing agricultural input utilization and reducing resource waste,particularly in the context of three pillars of crop management,i.e.,nutrient,irrigation,and weed management. 展开更多
关键词 Agriculture artificial intelligence crop management NUTRIENT IRRIGATION weed management resource use efficiency
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Risk factors and predictive model of adrenocortical insuffi ciency in patients with traumatic brain injury 被引量:8
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作者 Gui-long Feng Miao-miao Zheng +6 位作者 Shi-hong Yao Yin-qi Li Shao-jun Zhang Wei-jing Wen Kai Fan Jia-li Zhang Xiao Zhang 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2021年第3期179-184,共6页
BACKGROUND:Neuroendocrine dysfunction after traumatic brain injury(TBI)has received increased attention due to its impact on the recovery of neural function.The purpose of this study is to investigate the incidence an... BACKGROUND:Neuroendocrine dysfunction after traumatic brain injury(TBI)has received increased attention due to its impact on the recovery of neural function.The purpose of this study is to investigate the incidence and risk factors of adrenocortical insuffi ciency(AI)after TBI to reveal independent predictors and build a prediction model of AI after TBI.METHODS:Enrolled patients were grouped into the AI and non-AI groups.Fourteen preset impact factors were recorded.Patients were regrouped according to each impact factor as a categorical variable.Univariate and multiple logistic regression analyses were performed to screen the related independent risk factors of AI after TBI and develop the predictive model.RESULTS:A total of 108 patients were recruited,of whom 34(31.5%)patients had AI.Nine factors(age,Glasgow Coma Scale[GCS]score on admission,mean arterial pressure[MAP],urinary volume,serum sodium level,cerebral hernia,frontal lobe contusion,diff use axonal injury[DAI],and skull base fracture)were probably related to AI after TBI.Three factors(urinary volume[X4],serum sodium level[X5],and DAI[X8])were independent variables,based on which a prediction model was developed(logit P=-3.552+2.583X4+2.235X5+2.269X8).CONCLUSIONS:The incidence of AI after TBI is high.Factors such as age,GCS score,MAP,urinary volume,serum sodium level,cerebral hernia,frontal lobe contusion,DAI,and skull base fracture are probably related to AI after TBI.Urinary volume,serum sodium level,and DAI are the independent predictors of AI after TBI. 展开更多
关键词 Adrenocortical insuffi ciency Risk factor PREDICTOR Traumatic brain injury
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Effect of sedation on short-term and long-term outcomes of critically ill patients with acute respiratory insufficiency 被引量:7
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作者 Xue-zhong Xing Yong Gao +6 位作者 Hai-jun Wang Shi-ning Qu Chu-lin Huang Hao Zhang Hao Wang Qing-ling Xiao Ke-lin Sun 《World Journal of Emergency Medicine》 CAS 2015年第2期147-152,共6页
BACKGROUND: The present study aimed to determine the short-term and long-term outcomes of critically ill patients with acute respiratory insuffi ciency who had received sedation or no sedation.METHODS: The data of 91 ... BACKGROUND: The present study aimed to determine the short-term and long-term outcomes of critically ill patients with acute respiratory insuffi ciency who had received sedation or no sedation.METHODS: The data of 91 patients who had received mechanical ventilation in the first 24 hours between November 2008 and October 2009 were retrospectively analyzed. These patients were divided into two groups: a sedation group(n=28) and a non-sedation group(n=63). The patients were also grouped in two groups: deep sedation group and daily interruption and /or light sedation group.RESULTS: Overall, the 91 patients who had received ventilation ≥48 hours were analyzed. Multivariate analysis demonstrated two independent risk factors for in-hospital death: sequential organ failure assessment score(P=0.019, RR 1.355, 95%CI 1.051–1.747, B=0.304, SE=0.130, Wald=50483) and sedation(P=0.041, RR 5.015, 95%CI 1.072–23.459, B=1.612, SE=0.787, Wald=4.195). Compared with the patients who had received no sedation, those who had received sedation had a longer duration of ventilation, a longer stay in intensive care unit and hospital, and an increased in-hospital mortality rate. The Kaplan-Meier method showed that patients who had received sedation had a lower 60-month survival rate than those who had received no sedation(76.7% vs. 88.9%, Log-rank test=3.630, P=0.057). Compared with the patients who had received deep sedation, those who had received daily interruption or light sedation showed a decreased in-hospital mortality rate(57.1% vs. 9.5%, P=0.008). The 60-month survival of the patients who had received deep sedation was signifi cantly lower than that of those who had daily interruption or light sedation(38.1% vs. 90.5%, Log-rank test=6.783, P=0.009).CONCLUSIONS: Sedation was associated with in-hospital death. The patients who had received sedation had a longer duration of ventilation, a longer stay in intensive care unit and in hospital, and an increased in-hospital mortality rate compared with the patients who did not receive sedation. Compared with daily interruption or light sedation, deep sedation increased the in-hospital mortality and decreased the 60-month survival for patients who had received sedation. 展开更多
关键词 SEDATION Respiratory insuffi ciency PROGNOSIS Critical illness
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Proteinuria in paediatric patients with human immunodefi ciency virus infection 被引量:1
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作者 Vania Giacomet Paola Erba +3 位作者 Francesca Di Nello Sonia Coletto Alessandra Viganò Gian Vincenzo Zuccotti 《World Journal of Clinical Cases》 SCIE 2013年第1期13-18,共6页
In human immunodef iciency virus(HIV)-infected people kidney disease is as an important cause of morbidity and mortality. Clinical features of kidney damage in HIV-infected patients range from asymptomatic microalbumi... In human immunodef iciency virus(HIV)-infected people kidney disease is as an important cause of morbidity and mortality. Clinical features of kidney damage in HIV-infected patients range from asymptomatic microalbuminuria to nephrotic syndrome. The lack of specif ic clinical features despite the presence of heavy proteinuria may mask the renal involvement. Indeed, it is important in HIV patients to monitor renal function to early discover a possible kidney injury. After the introduction of antiretroviral therapy, mortality and morbidity associated to HIV-infection have shown a substantial reduction, although a variety of side effects for longterm use of highly active antiretroviral therapy, including renal toxicity, has emerged. Among more than 20 currently available antiretroviral agents, many of them can occasionally cause reversible or irreversible nephrotoxicity. At now, three antiretroviral agents, i.e., indinavir, atazanavir and tenofovir disoproxil fumarate have a well established association with direct nephrotoxicity. This review focuses on major causes of proteinuria and other pathological f indings related to kidney disease in HIV-infected children and adolescents. 展开更多
关键词 HUMAN IMMUNODEFIciency virus-infection NEPHROPATHY PROTEINURIA ANTIRETROVIRAL therapy Children
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Measuring effi ciency of listed tourism companies in China
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作者 SUN Yuan-yuan 《Ecological Economy》 2015年第1期72-80,共9页
This study seeks to evaluate the comparative productivity of 32 listed tourism companies which are the main suppliers of China tourism, using the popular methodology known as the data envelopment analysis(DEA). This s... This study seeks to evaluate the comparative productivity of 32 listed tourism companies which are the main suppliers of China tourism, using the popular methodology known as the data envelopment analysis(DEA). This study analyzes the productivity of listed tourism companies from business and region aspects based on the calculation of Malmquist index. The results show that(1) the overall productivity is non-effi cient(0.954);(2) the productivity of accommodation and catering is biggest, which shows the tourism develops quickly with supports from technology;(3) the productivity in western China is highest, where the economy and tourism attraction are better than other regions; and(4) the effi ciency differences among the listed tourism companies are not signifi cant, and they attribute to the scale effi-ciency, that is the input of the fi nance, resource, talents and policy. 展开更多
关键词 LISTED TOURISM COMPANIES OPERATIONAL effi ciency MALMQUIST index DEA China
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Smart Nutrient Deficiency Prediction System for Groundnut Leaf
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作者 Janani Malaisamy JebakumarRethnaraj 《Intelligent Automation & Soft Computing》 SCIE 2023年第5期1845-1862,共18页
Prediction of the nutrient deficiency range and control of it through application of an appropriate amount of fertiliser at all growth stages is critical to achieving a qualitative and quantitative yield.Distributing f... Prediction of the nutrient deficiency range and control of it through application of an appropriate amount of fertiliser at all growth stages is critical to achieving a qualitative and quantitative yield.Distributing fertiliser in optimum amounts will protect the environment’s condition and human health risks.Early identification also prevents the disease’s occurrence in groundnut crops.A convo-lutional neural network is a computer vision algorithm that can be replaced in the place of human experts and laboratory methods to predict groundnut crop nitro-gen nutrient deficiency through image features.Since chlorophyll and nitrogen are proportionate to one another,the Smart Nutrient Deficiency Prediction System(SNDP)is proposed to detect and categorise the chlorophyll concentration range via which nitrogen concentration can be known.The model’sfirst part is to per-form preprocessing using Groundnut Leaf Image Preprocessing(GLIP).Then,in the second part,feature extraction using a convolution process with Non-negative ReLU(CNNR)is done,and then,in the third part,the extracted features areflat-tened and given to the dense layer(DL)layer.Next,the Maximum Margin clas-sifier(MMC)is deployed and takes the input from DL for the classification process tofind CCR.The dataset used in this work has no visible symptoms of a deficiency with three categories:low level(LL),beginning stage of low level(BSLL),and appropriate level(AL).This model could help to predict nitrogen deficiency before perceivable symptoms.The performance of the implemented model is analysed and compared with ImageNet pre-trained models.The result shows that the CNNR-MMC model obtained the highest training and validation accuracy of 99%and 95%,respectively,compared to existing pre-trained models. 展开更多
关键词 CNN CHLOROPHYLL groundnut crop deep learning nitrogen deficiency
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Input-output Efficiency of Elements of Urban Construction Land in Beijing: Empirical Analysis Based on Panel Data of Jurisdiction
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作者 GU Yuekun 《Journal of Landscape Research》 2020年第2期49-53,56,共6页
Based on the Data Envelopment Analysis method,and by using CCR and BCC model,Super Efficiency model and Malmquist model guided by input efficiency,the input-output efficiency of elements of urban construction land in ... Based on the Data Envelopment Analysis method,and by using CCR and BCC model,Super Efficiency model and Malmquist model guided by input efficiency,the input-output efficiency of elements of urban construction land in different jurisdictions of Beijing from 2005 to 2015 was studied.The results showed that there were obvious differences between input-output efficiency of elements of urban construction land in different jurisdictions of Beijing,among which the efficiency of the core area of capital,Yanqing District,Fangshan District and Huairou District was relatively high,while the efficiency of Daxing District,Fengtai District and Miyun District was relatively low.There was no obvious correlation between efficiency differentiation and location factors,which is mainly caused by whether the land use in each jurisdiction has scale effect,whether the technology is improved,whether the input is redundant and whether the output is insufficient.For the jurisdiction of inefficient land use,we should strengthen the consciousness of intensive land use,improve the technical level,appropriately reduce the redundancy of input elements,and pay attention to the output of social and ecological benefits. 展开更多
关键词 Data Envelopment Analysis Urban construction LAND INPUT and OUTPUT Effi ciency
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不同赋存形式H_(2)映震特征及机理分析
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作者 李娜 向阳 +1 位作者 李新勇 汪成国 《地震》 CSCD 北大核心 2024年第3期138-155,共18页
乌鲁木齐04泉水中溶解气H_(2)和阿克苏断层土壤气H_(2)监测点均属新疆地震监测预报评估A类。本文以二者为研究对象,分析不同赋存形式H_(2)浓度的动态变化特征;利用R值评分方法和Molchan图表法对H_(2)浓度进行映震效能检验,并提取异常指... 乌鲁木齐04泉水中溶解气H_(2)和阿克苏断层土壤气H_(2)监测点均属新疆地震监测预报评估A类。本文以二者为研究对象,分析不同赋存形式H_(2)浓度的动态变化特征;利用R值评分方法和Molchan图表法对H_(2)浓度进行映震效能检验,并提取异常指标;探讨和分析不同赋存形式H_(2)的映震机理。结论如下:乌鲁木齐04泉水中溶解气H_(2)浓度受气象因素影响较小,而阿克苏断层土壤气H_(2)浓度受气压和气温双重影响,其中以气温影响为主。R值评分方法和Molchan图表法检验显示,两个监测点均具有较好的短期预测效能。H_(2)浓度测项具有较好的短临预测效能,这得益于H_(2)的物理化学性质稳定且迁移速度极快。 展开更多
关键词 地震监测 H_(2) 影响因素 映震效能 异常指标 机理
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基于Cuk变换的MCR-WPT系统阻抗匹配研究
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作者 姜建国 江骁 《化工自动化及仪表》 CAS 2024年第6期1123-1128,共6页
在分析无线充电系统的基础上,在发射端检测电流电压相位并加入锁相环调整系统频率,使系统处于谐振状态,提升系统的传输效率。同时,为满足无线充电系统在不同负载阻值下都具有较高效率,在负载端接入Cuk变换器并采用PID控制策略实现系统... 在分析无线充电系统的基础上,在发射端检测电流电压相位并加入锁相环调整系统频率,使系统处于谐振状态,提升系统的传输效率。同时,为满足无线充电系统在不同负载阻值下都具有较高效率,在负载端接入Cuk变换器并采用PID控制策略实现系统恒功率输出。用Simulink仿真平台搭建模型,当系统处于谐振状态后,负载阻值在20、30、40Ω时系统传输效率最终稳定在0.84,并且稳定持续输出5 kW的功率。 展开更多
关键词 无线充电 阻抗匹配 CUK变换器 锁相环 传输效率
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基于DEA-Malmquist指数模型风电企业融资效率研究
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作者 侯新 汪林峰 《吉林金融研究》 2024年第6期27-33,共7页
风电产业作为国家战略性新兴产业,对经济发展和环境保护具有举足轻重的地位。近10年来,在国家政策的大力推动下,该行业发展迅速。但是,自疫情爆发以来,国内的很多风电企业都面临着生存危机,随着后疫情时代的到来,中国风电行业面临新的... 风电产业作为国家战略性新兴产业,对经济发展和环境保护具有举足轻重的地位。近10年来,在国家政策的大力推动下,该行业发展迅速。但是,自疫情爆发以来,国内的很多风电企业都面临着生存危机,随着后疫情时代的到来,中国风电行业面临新的机遇与挑战,更在技术经济和融资方面出现了新问题,制约了其发展。本文采用DEA-Malmquist模型,对风电行业的17家企业进行静态及动态融资效率分析。研究结果表明,规模效率和纯技术效率是制约风电企业融资效率提升的主要因素。同时,结合Malmquist指数模型发现,技术进步指数对融资效率的提升具有显著影响。根据上述分析结果,为风电企业融资效率的提升提出具体的建议和意见,为风电企业解决融资问题提供参考。 展开更多
关键词 融资效率 风电企业 DEA MALMQUIST指数
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数字基础设施建设如何影响民营企业投资效率——营商环境的中介效应
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作者 苏斌 刘露露 《吉林金融研究》 2024年第5期19-28,78,共11页
为探究数字基础设施建设对中国民营企业投资效率的影响,并考察营商环境在其中的中介作用。基于2013-2022年中国30个省级行政区和上市民营企业的面板数据,采用双向固定效应模型与中介效应模型进行经验分析。研究结果显示,数字基础设施建... 为探究数字基础设施建设对中国民营企业投资效率的影响,并考察营商环境在其中的中介作用。基于2013-2022年中国30个省级行政区和上市民营企业的面板数据,采用双向固定效应模型与中介效应模型进行经验分析。研究结果显示,数字基础设施建设显著提升了上市民营企业的投资效率,并有效缓解了企业投资不足与投资过度的问题。营商环境的中介效应检验结果表明,数字基础设施建设优化了营商环境,通过聚集人才和吸引投入促进了民营企业投资效率的提升。异质性分析显示,改善的数字基础设施在经济发达的东部地区对解决民营企业的投资过度和不足问题更为显著,而在经济发展相对落后的中西部地区,其改善主要集中于解决企业的投资不足问题。综上所述,针对民营企业投资疲软的现实困境,应当加快数字基础设施投资与建设,释放数字红利,并进一步发挥数字基础设施建设对营商环境的改善作用,以助力民营企业实现投资效率的提升与高质量发展。 展开更多
关键词 数字基础设施建设 投资效率 营商环境 民营企业
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游戏化教学策略在模具设计课程中的实施与评估
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作者 陈茜 文杰 《模具工业》 2024年第4期73-79,共7页
探讨了游戏化教学策略在模具设计课程中的实施并进行了效果评估,通过综合运用理论分析和实证研究,考察了游戏化教学的核心元素及其如何融入模具设计教学中。通过引入游戏元素,分析其对提升学生学习动机、认知能力、情感态度和合作交流... 探讨了游戏化教学策略在模具设计课程中的实施并进行了效果评估,通过综合运用理论分析和实证研究,考察了游戏化教学的核心元素及其如何融入模具设计教学中。通过引入游戏元素,分析其对提升学生学习动机、认知能力、情感态度和合作交流的影响,并分析和评估该策略的有效性,发现游戏化教学提高了学生的课堂参与度和学习成效,学生对游戏元素的接受度高,反馈积极,显示游戏化教学在增强学习体验方面的有效性。此外,教学实践的成果分析表明,游戏化教学有助于学生更好地掌握模具设计的专业知识和技能,为高职模具设计课程的教学改革提供了新的视角和方法,展示了游戏化教学在技术教育领域的潜力和价值。 展开更多
关键词 游戏化教学 模具设计 高职教育 学习成效 教学策略
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碳交易政策对城市能源利用效率的影响及机制
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作者 李珊珊 马艳芹 《工业技术经济》 CSSCI 北大核心 2024年第8期90-99,共10页
能源利用效率提升是实现碳达峰战略目标的重要抓手。本文将能源利用效率区分为单要素能源生产率与绿色全要素能源效率,以2004~2022年我国284个地级市为研究样本,运用双重差分、连续型双重差分等方法考察检验碳交易政策对试点城市能源利... 能源利用效率提升是实现碳达峰战略目标的重要抓手。本文将能源利用效率区分为单要素能源生产率与绿色全要素能源效率,以2004~2022年我国284个地级市为研究样本,运用双重差分、连续型双重差分等方法考察检验碳交易政策对试点城市能源利用效率的影响及机制。结果显示:碳交易政策能显著提升城市单要素能源生产率与全要素能源效率,且政策效应随年份推移越发显著。机制分析表明:碳价上升有助于改善城市单要素能源生产率与全要素能源效率;碳交易政策能通过能源资源错配的纠正改善城市单要素能源生产率与全要素能源效率,而绿色技术创新的中介影响为负。碳交易政策有助于提升非资源型城市、非老工业基地城市单要素能源生产率与全要素能源效率,而对老工业基地城市单要素能源生产率存在抑制作用。本文基于城市能源利用效率提升的视角,为全国范围碳交易市场建设提供政策启示。 展开更多
关键词 碳达峰 碳交易政策 单要素能源生产率 绿色全要素能源效率 双重差分 连续型双重差分 能源资源错配 绿色技术创新
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静脉腔内激光闭合术和内镜深筋膜下穿通静脉离断术治疗下肢静脉曲张伴病理性穿通静脉功能不全的临床效果研究
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作者 于家祥 姜俊义 《临床普外科电子杂志》 2024年第3期36-40,共5页
目的观察静脉腔内激光闭合术(endovenous laser ablation,EVLA)和内镜深筋膜下穿通静脉离断术(subfascial endoscopic perforator surgery,SEPS)治疗下肢静脉曲张伴病理性穿通静脉功能不全的临床效果。方法选取2021年4月至2024年3月敦... 目的观察静脉腔内激光闭合术(endovenous laser ablation,EVLA)和内镜深筋膜下穿通静脉离断术(subfascial endoscopic perforator surgery,SEPS)治疗下肢静脉曲张伴病理性穿通静脉功能不全的临床效果。方法选取2021年4月至2024年3月敦化市医院诊治的83例下肢静脉曲张伴病理性穿通静脉功能不全患者,根据治疗方式不同分为EVLA组(n=42)、SEPS组(n=41)。对比两组患者手术相关指标、疼痛程度、应激反应、生活质量。结果EVLA组患者的手术用时、切口长度、住院时长、术后卧床时长均短于SEPS组,术中失血量少于SEPS组,差异均有显著性(P<0.05)。两组患者术后的并发症发生率无显著差异(P>0.05)。术后3、12、24、48h,EVLA组患者的NRS评分均低于SEPS组,差异均有显著性(P<0.05)。术前,两组患者的皮质醇及肾上腺素水平无显著差异(P>0.05)。术后2d,两组患者的皮质醇、肾上腺素水平较术前升高,且EVLA组的皮质醇及肾上腺素水平低于SEPS组,差异均有显著性(P<0.05)。术前,两组患者的慢性静脉功能不全问卷(chronic venous insuffi ciency questionnaire,CIVIQ)评分无显著差异(P>0.05)。术后3个月,两组患者的CIVIQ评分较术前均升高,EVLA组的CIVIQ评分高于SEPS组,差异有显著性(P<0.05)。结论对于下肢静脉曲张伴病理性穿通静脉功能不全的患者,EVLA、SEPS在降低并发症发生率方面效果相似,但EVLA可缩短患者康复时间,减轻患者应激反应与机体疼痛感,并提高患者的生活质量。 展开更多
关键词 静脉腔内激光闭合术 内镜深筋膜下穿通静脉离断术 下肢静脉曲张 病理性穿通静脉功能不全 疼痛程度 应激反应
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基于知识关联分析的科技成果转化效率测度方法研究 被引量:2
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作者 田常伟 董坤 +1 位作者 郭锐 林艳秋 《情报理论与实践》 CSSCI 北大核心 2024年第5期123-130,共8页
[目的/意义]科技成果转化是科学技术转变为现实生产力的关键环节,客观评价科技成果转化效率是促进科技成果转化的重要前提。[方法/过程]首先,采用BERTopic主题模型识别科学、技术和产业主题;其次,融合直接关联与间接关联计算主题关联度... [目的/意义]科技成果转化是科学技术转变为现实生产力的关键环节,客观评价科技成果转化效率是促进科技成果转化的重要前提。[方法/过程]首先,采用BERTopic主题模型识别科学、技术和产业主题;其次,融合直接关联与间接关联计算主题关联度,并结合主题分布时间识别知识关联路径;再次,构建科学知识转化强度、科学知识转化速度、技术知识转化强度和技术知识转化速度等指标测度科学知识转化效率与技术知识转化效率;最后,以工业机器人领域为例进行实证研究。[结果/结论]该方法能够充分挖掘科技成果转化过程中科学、技术、产业要素的知识关联特征,可以面向科技成果转化全链条进行效率测度,分析过程与结果具有较好的可行性与有效性。 展开更多
关键词 科技成果转化 知识关联 知识转化 效率测度 工业机器人
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苹果渣饲料在畜牧生产中的应用
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作者 张建梅 谢全喜 +4 位作者 张杰 赵金 刘敬博 孙国政 汪官保 《饲料工业》 CAS 北大核心 2024年第18期138-143,共6页
苹果渣富含多种营养成分,作为一种非常规饲料原料饲喂动物,不仅可以节约养殖成本,还可以提高生产效益。目前,苹果渣饲料的使用方式主要有两种,即使用干果渣直接饲喂或经发酵后再进行饲喂动物,文章主要针对苹果渣饲料的在畜牧生产中的添... 苹果渣富含多种营养成分,作为一种非常规饲料原料饲喂动物,不仅可以节约养殖成本,还可以提高生产效益。目前,苹果渣饲料的使用方式主要有两种,即使用干果渣直接饲喂或经发酵后再进行饲喂动物,文章主要针对苹果渣饲料的在畜牧生产中的添加比例及使用效果进行综述,以期为苹果渣的实际应用提供指导。 展开更多
关键词 苹果渣 畜禽生产 发酵苹果渣 生产效率 微生物发酵
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从芍药甘草汤方证与药量探讨胞轮振跳的治疗
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作者 晏振东 李艳鹏 +3 位作者 张佳琪 刘艺 马乾 陈明 《中国中医眼科杂志》 2024年第1期53-55,共3页
胞轮振跳是临床中的难治性疾病,该病严重影响患者的情绪及生活质量。目前临床治疗手段有限,西医多以手术为主,且容易反复,创伤性较大。中医药治疗该病不良反应少且疗效稳固。芍药甘草汤主治肝脾阴虚证,而胞轮振跳的病机之一则为肝脾阴虚... 胞轮振跳是临床中的难治性疾病,该病严重影响患者的情绪及生活质量。目前临床治疗手段有限,西医多以手术为主,且容易反复,创伤性较大。中医药治疗该病不良反应少且疗效稳固。芍药甘草汤主治肝脾阴虚证,而胞轮振跳的病机之一则为肝脾阴虚,这是与芍药甘草汤证的契合点。因此,根据异病同治原则,该方治疗此类疾病是辨病与辨证结合的临床思路的体现。通过文献考证古今度量衡质量的单位换算,芍药(白芍)与炙甘草的用量需达60 g以上方可获得良好临床疗效。本文总结了芍药甘草汤的临床使用经验,并结合文献从方义与药量角度论证其治疗胞轮振跳的可行性与合理性。 展开更多
关键词 芍药甘草汤 眼轮匝肌痉挛 胞轮振跳 肝脾阴虚 药量
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功能性产业政策能否促进企业生产率增长——基于《中国制造2025》的准自然实验 被引量:1
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作者 戴魁早 陈阿丽 杨新宇 《南开经济研究》 CSSCI 北大核心 2024年第2期43-63,共21页
本文在政府与市场关系分析框架下,理论分析制造强国战略这一功能性产业政策对企业全要素生产率的影响机制,并以《中国制造2025》为准自然实验,结合2010—2019年沪深A股上市公司数据,运用双重差分法对理论预期进行验证。研究发现,制造强... 本文在政府与市场关系分析框架下,理论分析制造强国战略这一功能性产业政策对企业全要素生产率的影响机制,并以《中国制造2025》为准自然实验,结合2010—2019年沪深A股上市公司数据,运用双重差分法对理论预期进行验证。研究发现,制造强国战略这一功能性产业政策显著地促进了制造业企业全要素生产率增长,这一结论在安慰剂检验、PSM-DID、工具变量法等一系列稳健性检验后仍然成立。制造强国战略的这种影响是通过协同创新、关键核心技术突破等技术创新机制,以及专业技术人才、经营管理人才等人才支撑机制实现的。政府治理效能提升显著增强了制造强国战略的实施效果,而且这种影响对于政府效率和营商环境排名前50的城市更显著。政府治理效能提升强化了制造强国战略的协同创新、关键核心技术突破、专业技术人才支撑和经营管理人才支撑等机制,但未明显改善创新溢出机制和技能人才支撑机制。此外,异质性分析表明,制造强国战略对试点地区、配套政策完善地区、融资约束程度较低、智能化水平较高、技术差距较大行业的企业生产率提升效果更为显著。本文的研究验证了制造强国战略在制造业生产率增长方面的重要作用,为功能性产业政策实施与制造业高质量发展提供了有益的参考依据。 展开更多
关键词 产业政策 中国制造2025 政府治理效能 高质量发展
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高质量发展背景下养老服务机构效率测度、空间网络结构特征及其影响因素 被引量:2
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作者 张园 《社会保障评论》 CSSCI 2024年第1期107-125,共19页
效率是养老服务高质量发展的重要体现,论文从空间地理视角研究养老服务机构效率问题,基于窗口DEA模型测度了我国2011—2020年29个省份养老服务机构的效率值及变动趋势,然后采用修正引力模型构建省际间空间关联矩阵,结合社会网络分析方法... 效率是养老服务高质量发展的重要体现,论文从空间地理视角研究养老服务机构效率问题,基于窗口DEA模型测度了我国2011—2020年29个省份养老服务机构的效率值及变动趋势,然后采用修正引力模型构建省际间空间关联矩阵,结合社会网络分析方法,揭示了养老服务机构效率空间关联网络的结构特征及影响因素,研究表明:①养老服务机构效率存在中、东、西部区域差异和不均衡性,且区域差距随着时间推移逐步扩大。②样本考察期内养老服务机构效率空间网络关联程度呈上升趋势,网络结构具有较强的稳健性,等级特征不显著。东部省份扮演“引领者”和“行动者”的角色,中西部省份扮演“边缘行动者”的角色。③浙江、广东等省份属于“净溢出板块”,河北、山东等省份属于“经纪人板块”,内蒙古、上海等省份属于“净受益板块”,板块之间显著关联。④养老服务机构分布密度差异、地理邻近、人力投入差异因素对养老服务机构效率空间网络的形成产生正向影响。最后从构建跨区域协同发展机制、推动网络空间板块间和区域间均衡发展、综合考虑影响因素发挥空间溢出效应提出建议。 展开更多
关键词 窗口DEA模型 养老服务机构效率 空间关联网络 社会网络分析 QAP回归
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碱液电解槽建模与宽范围运行控制
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作者 胡致远 程浩然 +1 位作者 夏杨红 韦巍 《电力自动化设备》 EI CSCD 北大核心 2024年第11期17-23,共7页
在碱液电解制氢中,碱液电解槽(AWE)的低载性能差,难以宽范围跟踪波动性可再生能源出力。基于工业AWE的内部结构和工作原理,建立了一种新的工业AWE等效电路模型,揭示了AWE低载低效率的内在机理,并提出了一种多模态自寻优(MMSO)控制策略... 在碱液电解制氢中,碱液电解槽(AWE)的低载性能差,难以宽范围跟踪波动性可再生能源出力。基于工业AWE的内部结构和工作原理,建立了一种新的工业AWE等效电路模型,揭示了AWE低载低效率的内在机理,并提出了一种多模态自寻优(MMSO)控制策略及其原理样机。在低载时施加低频脉冲电流以提高制氢效率,从而实现工业AWE的宽范围运行。基于10 kW的AWE实验平台,验证了所提模型的正确性以及所提MMSO控制策略对AWE在低载范围内效率的提升具有显著的效果。 展开更多
关键词 制氢 碱液电解槽 变流器 宽范围运行 效率提升
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