期刊文献+
共找到1,150篇文章
< 1 2 58 >
每页显示 20 50 100
Risk Factors for Geo-Helminthiasis in Children Aged 6 - 36 Months in a Rural Health District in Cameroon
1
作者 Isabelle Mekone Nkwele Monono Naiza +6 位作者 Gervais Talla Kamga Hugues Nana Djeunga Jeannette Epée Ngoue Patricia Epée Eboumbou Suzanne Ngo Um Sap Evelyn Mah Mungeh Joseph Kamgno 《Open Journal of Pediatrics》 2024年第2期391-400,共10页
Introduction and Objectives: Soil-Transmitted-Helminthiasis (STH) is a public health problem in Cameroon. The control strategies currently in place, particularly chemoprevention, has shortcomings linked to the target ... Introduction and Objectives: Soil-Transmitted-Helminthiasis (STH) is a public health problem in Cameroon. The control strategies currently in place, particularly chemoprevention, has shortcomings linked to the target population, which are school-age children. The objective was to determine the prevalence and the risk factors associated with geo-helminthiasis in children aged 0 to 3 years in a rural health district. Method: From December 2020 to May 2021, a descriptive and analytical cross-sectional study of 376 children between 6 and 36 months was carried out in the Akonolinga health district. This was a cluster sampling in 4 health areas. Stool samples were collected and analysed using the mini-FLOTAC method. The results expressed as the number of eggs per gram of stool. A questionnaire on socio-demographic and lifestyle data was administered to the parents. The Chi-squared test was used to measure the association between geo-helminth infection and the data collected. A multivariate analysis using logistic regression was performed (p 0.05). Results: The prevalence of STH was 19.4% (Ascaris lumbricoides: 16% and Trichuris trichiura: 8%). Risk factors were: consumption of contaminated water (AOR = 1.93 [1.03 - 3.6];p = 0.040), early contact of the child with the ground (before age of 4 months) (AOR = 4.9 [2.1 - 11.37];p .001), habit of walking barefoot (AOR = 2.91 [1.1 - 7.97];p = 0.038), and living in a habitat with unpaved ground (AOR = 7.4 [1.55 - 35.7];p = 0.012). Conclusion: The prevalence of STHs in infants was high. Preventive chemotherapy should be extended to this age-group, and other measures intensified. 展开更多
关键词 Akonolinga Soil-Transmitted-Helminths Children Aged 0 - 3 Years risk Factors
下载PDF
Migration and transfer of chromium in soil-vegetable system and associated health risks in vicinity of ferro-alloy manufactory 被引量:6
2
作者 廖映平 王振兴 +3 位作者 杨志辉 柴立元 陈建群 袁平夫 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第11期2520-2527,共8页
Study was carried out to analyze the distribution and migration patterns,soil-to-plant transfer and potential health risks of chromium in soil-vegetable system in areas near a ferro-alloy manufactory in Hunan province... Study was carried out to analyze the distribution and migration patterns,soil-to-plant transfer and potential health risks of chromium in soil-vegetable system in areas near a ferro-alloy manufactory in Hunan province.The results show that soils near sewer outlet,sewer channel and in control area are averaged 2 239.5,995.33 and 104.9 mg/kg,respectively.The total Cr has a relative accumulation in soil depth of 200-400 mm near the sewer outlet,mainly enriches in the surface layer(0-200 mm) near the sewer channel and decreases gradually in unpolluted soils.The differential concentration level of enrichment between layers is little.The results also indicate that the three vegetables of celery,lettuce and Chinese cabbage are able to convert the potentially toxic Cr(Ⅵ) species into the non-toxic Cr(Ⅲ) species,and the chromium contents in the edible parts of the vegetables are averaged 11.95 mg/kg.The transfer factors of the three vegetables follow the order:Chinese cabbage lettuce celery.The estimated total daily intake of chromium substantially exceeds the dietary allowable value,which may pose health risks to local population. 展开更多
关键词 heavy metal CHROMIUM MIGRATION transfer factor health risk soil VEGETABLE
下载PDF
基于ISM-SD的地下洞室群施工进度风险传递路径研究
3
作者 黄建文 谭永祎 +3 位作者 陈梦媛 王兴霞 姜海龙 江谊园 《水电能源科学》 北大核心 2024年第1期93-97,共5页
针对水电工程地下洞室群施工进度风险存在传递问题,提出了基于解释结构模型(ISM)和系统动力学(SD)的地下洞室群施工进度风险传递路径分析方法。根据地下洞室群的施工特点,建立了地下洞室群施工进度风险指标体系;结合风险传递机理,运用... 针对水电工程地下洞室群施工进度风险存在传递问题,提出了基于解释结构模型(ISM)和系统动力学(SD)的地下洞室群施工进度风险传递路径分析方法。根据地下洞室群的施工特点,建立了地下洞室群施工进度风险指标体系;结合风险传递机理,运用解释结构模型分析风险因素间传递关系,建立了风险因素传递矩阵,并总结归纳出风险因素关系对照表,通过系统动力学分析风险因素间传递路径,揭示了施工进度风险传递路径网络;集成ISM-SD构建了地下洞室群施工进度风险传递路径分析模型,并结合西南地区某大型水电站地下洞室群工程进行分析。结果表明,该方法可有效识别施工进度风险重要因素和关键传递路径,为地下洞室群施工进度风险管理提供了决策依据。 展开更多
关键词 地下洞室群 施工进度风险 风险传递路径 解释结构模型 系统动力学
下载PDF
Knowledge Transfer Learning via Dual Density Sampling for Resource-Limited Domain Adaptation 被引量:1
4
作者 Zefeng Zheng Luyao Teng +2 位作者 Wei Zhang Naiqi Wu Shaohua Teng 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第12期2269-2291,共23页
Most existing domain adaptation(DA) methods aim to explore favorable performance under complicated environments by sampling.However,there are three unsolved problems that limit their efficiencies:ⅰ) they adopt global... Most existing domain adaptation(DA) methods aim to explore favorable performance under complicated environments by sampling.However,there are three unsolved problems that limit their efficiencies:ⅰ) they adopt global sampling but neglect to exploit global and local sampling simultaneously;ⅱ)they either transfer knowledge from a global perspective or a local perspective,while overlooking transmission of confident knowledge from both perspectives;and ⅲ) they apply repeated sampling during iteration,which takes a lot of time.To address these problems,knowledge transfer learning via dual density sampling(KTL-DDS) is proposed in this study,which consists of three parts:ⅰ) Dual density sampling(DDS) that jointly leverages two sampling methods associated with different views,i.e.,global density sampling that extracts representative samples with the most common features and local density sampling that selects representative samples with critical boundary information;ⅱ)Consistent maximum mean discrepancy(CMMD) that reduces intra-and cross-domain risks and guarantees high consistency of knowledge by shortening the distances of every two subsets among the four subsets collected by DDS;and ⅲ) Knowledge dissemination(KD) that transmits confident and consistent knowledge from the representative target samples with global and local properties to the whole target domain by preserving the neighboring relationships of the target domain.Mathematical analyses show that DDS avoids repeated sampling during the iteration.With the above three actions,confident knowledge with both global and local properties is transferred,and the memory and running time are greatly reduced.In addition,a general framework named dual density sampling approximation(DDSA) is extended,which can be easily applied to other DA algorithms.Extensive experiments on five datasets in clean,label corruption(LC),feature missing(FM),and LC&FM environments demonstrate the encouraging performance of KTL-DDS. 展开更多
关键词 Cross-domain risk dual density sampling intra-domain risk maximum mean discrepancy knowledge transfer learning resource-limited domain adaptation
下载PDF
海南琼中岩-土体系重金属迁移特征及表土环境质量评价
5
作者 赵红坤 唐世新 +4 位作者 付燕刚 兰瑞烜 赵克强 李晓东 马生明 《岩矿测试》 CAS CSCD 北大核心 2024年第1期137-151,共15页
地球关键带和土壤重金属污染是当今研究的前沿与热点,岩-土体系是地球关键带的重要组成部分。目前海南岛针对不同成壤母质岩-土体系的详细研究较少,并且重金属亟需基于新标准进行评价。为了查清岩-土体系中重金属元素迁移特征及污染状况... 地球关键带和土壤重金属污染是当今研究的前沿与热点,岩-土体系是地球关键带的重要组成部分。目前海南岛针对不同成壤母质岩-土体系的详细研究较少,并且重金属亟需基于新标准进行评价。为了查清岩-土体系中重金属元素迁移特征及污染状况,本文以海南岛琼中3个土壤垂向剖面及7115件表层土壤样品为研究对象,采用电感耦合等离子体质谱/发射光谱法(ICP-MS/OES)和原子荧光光谱法(AFS)等分析方法,测定岩石和土壤中Cu、Pb、Zn、Cr、Ni、Cd、As和Hg共8种重金属元素含量,利用土壤环境质量农用地土壤污染风险管控标准、内梅罗指数法和潜在生态危害指数法定量评价了表层土壤样品重金属污染状况及生态风险。结果表明,①海南岛琼中二长花岗岩岩-土体系中,不同重金属元素表现出明显的分异特征,Cu、Pb、Zn、Cr、Ni、Cd元素以亏损为主,As元素以富集为主,Hg元素则表现出不同的富集或亏损特征,As、Hg元素尤其富集在表层。②琼中绝大多数表层土壤中重金属元素含量低于土壤环境质量农用地土壤污染风险筛选值,土壤污染风险低。③以琼中和海南岛背景值为评价标准时,应关注Cr、Ni和As污染以及Hg、As和Cd的生态危害。以土壤环境质量为评价标准时,研究区表层土壤的环境质量总体清洁,生态风险较弱。 展开更多
关键词 -土体系 重金属元素 电感耦合等离子体质谱/发射光谱法(ICP-MS/OES) 原子荧光光谱法(AFS) 质量迁移 环境质量 生态风险评价 海南岛琼中
下载PDF
Corporate Governance, Enterprise Risk Management, and Inter-temporal Risk Transfer
6
作者 Antonio Renzi Gianluca Vagnani 《Journal of Modern Accounting and Auditing》 2020年第3期105-116,共12页
This work is an initial attempt to describe the interconnections among corporate governance,enterprise risk management,and the phenomena of inter-firm risk transfer that occurs in combination with firms’income smooth... This work is an initial attempt to describe the interconnections among corporate governance,enterprise risk management,and the phenomena of inter-firm risk transfer that occurs in combination with firms’income smoothing.Corporate governance is conceived as a set of rules according to which a firm is managed and governed by its top managers.Extant literature on corporate governance has pointed out the benefits of the adoption,at a firm level,of a comprehensive enterprise risk management process.We note that,although such an adoption favors the smoothing of a firm’s income,in smoothing the income a firm,it also gives rise to an inter-temporal transfer of risk from the firm itself to its stakeholders,specifically to suppliers and employees.Such transfer of risk depends on the strength of a firm contractual power and on the structural relationships established by a firm with its stakeholders.We therefore argue that larger-sized organizations affiliated with a business group are likely to smooth income to a greater extent than smaller-sized organizations unaffiliated with a business group.The paper also offers some discussions of the findings and points out some important issues to be addressed in future studies. 展开更多
关键词 enterprise risk management CORPORATE GOVERNANCE risk transfer net operating INCOME SMOOTHING
下载PDF
Research on Personal Credit Risk Assessment Model Based on Instance-Based Transfer Learning
7
作者 Maoguang Wang Hang Yang 《International Journal of Intelligence Science》 2021年第1期44-55,共12页
Personal credit risk assessment is an important part of the development of financial enterprises. Big data credit investigation is an inevitable trend of personal credit risk assessment, but some data are missing and ... Personal credit risk assessment is an important part of the development of financial enterprises. Big data credit investigation is an inevitable trend of personal credit risk assessment, but some data are missing and the amount of data is small, so it is difficult to train. At the same time, for different financial platforms, we need to use different models to train according to the characteristics of the current samples, which is time-consuming. <span style="font-family:Verdana;">In view of</span><span style="font-family:Verdana;"> these two problems, this paper uses the idea of transfer learning to build a transferable personal credit risk model based on Instance-based Transfer Learning (Instance-based TL). The model balances the weight of the samples in the source domain, and migrates the existing large dataset samples to the target domain of small samples, and finds out the commonness between them. At the same time, we have done a lot of experiments on the selection of base learners, including traditional machine learning algorithms and ensemble learning algorithms, such as decision tree, logistic regression, </span><span style="font-family:Verdana;">xgboost</span> <span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> so on. The datasets are from P2P platform and bank, the results show that the AUC value of Instance-based TL is 24% higher than that of the traditional machine learning model, which fully proves that the model in this paper has good application value. The model’s evaluation uses AUC, prediction, recall, F1. These criteria prove that this model has good application value from many aspects. At present, we are trying to apply this model to more fields to improve the robustness and applicability of the model;on the other hand, we are trying to do more in-depth research on domain adaptation to enrich the model.</span> 展开更多
关键词 Personal Credit risk Big Data Credit Investigation Instance-Based transfer Learning
下载PDF
Diagnostic performance of dynamic contrast-enhanced magnetic resonance imaging parameters and serum tumor markers in rectal carcinoma prognosis
8
作者 Ren-Qi Mu Jun-Wei Lv +3 位作者 Cai-Yun Ma Xiao-Hui Ma Dong Xing Hou-Sheng Ma 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第5期1796-1807,共12页
BACKGROUND Rectal carcinoma(RC),one of the most common malignancies globally,presents an increasing incidence and mortality year by year,especially among young people,which seriously affects the prognosis and quality ... BACKGROUND Rectal carcinoma(RC),one of the most common malignancies globally,presents an increasing incidence and mortality year by year,especially among young people,which seriously affects the prognosis and quality of life of patients.At present,dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)parameters and serum carbohydrate antigen 19-9(CA19-9)and CA125 Levels have been used in clinical practice to evaluate the T stage and differentiation of RC.However,the accuracy of these evaluation modalities still needs further research.This study explores the application and value of these methods in evaluating the T stage and differentiation degree of RC.AIM To analyze the diagnostic performance of DCE-MRI parameters combined with serum tumor markers(TMs)in assessing pathological processes and prognosis of RC patients.METHODS A retrospective analysis was performed on 104 RC patients treated at Yantai Yuhuangding Hospital from May 2018 to January 2022.Patients were categorized into stages T1,T2,T3,and T4,depending on their T stage and differentiation degree.In addition,they were assigned to low(L group)and moderate-high differentiation(M+H group)groups based on their differentiation degree.The levels of DCE-MRI parameters and serum CA19-9 and CA125 in different groups of patients were compared.In addition,the value of DCE-MRI parameters[volume transfer constant(Ktrans),rate constant(Kep),and extravascular extracellular volume fraction(Ve)in assessing the differentiation and T staging of RC patients was discussed.Furthermore,the usefulness of DCE-MRI parameters combined with serum CA19-9 and CA125 Levels in the evaluation of RC differentiation and T staging was analyzed.RESULTS Ktrans,Ve,CA19-9 and CA125 were higher in the high-stage group and L group than in the low-stage group and M+H Group,respectively(P<0.05).The areas under the curve(AUCs)of the Ktran and Ve parameters were 0.638 and 0.694 in the diagnosis of high and low stages,respectively,and 0.672 and 0.725 in diagnosing moderate-high and low differentiation,respectively.The AUC of DCE-MRI parameters(Ktrans+Ve)in the diagnosis of high and low stages was 0.742,and the AUC in diagnosing moderate-high and low differentiation was 0.769.The AUCs of CA19-9 and CA-125 were 0.773 and 0.802 in the diagnosis of high and low stages,respectively,and 0.834 and 0.796 in diagnosing moderate-high and low differentiation,respectively.Then,we combined DCE-MRI(Ktrans+Ve)parameters with CA19-9 and CA-125 and found that the AUC of DCE-MRI parameters plus serum TMs was 0.836 in the diagnosis of high and low stages and 0.946 in the diagnosis of moderate-high and low differentiation.According to the Delong test,the AUC of DCE-MRI parameters plus serum TMs increased significantly compared with serum TMs alone in the diagnosis of T stage and differentiation degree(P<0.001).CONCLUSION The levels of the DCE-MRI parameters Ktrans and Ve and the serum TMs CA19-9 and CA125 all increase with increasing T stage and decreasing differentiation degree of RC and can be used as indices to evaluate the differentiation degree of RC in clinical practice.Moreover,the combined evaluation of the above indices has a better effect and more obvious clinical value,providing important guiding importance for clinical condition judgment and treatment selection. 展开更多
关键词 Rectal carcinoma Volume transfer constant Rate constant Extravascular extracellular volume fraction Serum carbohydrate antigen 19-9 Serum carbohydrate antigen 125
下载PDF
Credit Risk Transfer and the Performance of Commercial Banks --Based on the Panel Data
9
作者 Wang shoufang 《International English Education Research》 2015年第6期22-27,共6页
Based on the panel data, we analyze the US commercial banks' CRT. According to the study, we find that the introduction of CRT will increase the level of banks' liquid risk. The performance of bank mainly is that it... Based on the panel data, we analyze the US commercial banks' CRT. According to the study, we find that the introduction of CRT will increase the level of banks' liquid risk. The performance of bank mainly is that its supervision and review of risk will drop, based on the impact of asymmetric information, commercial Banks transfer the bad loans to investors. Through the analysis we can see that after the transfer of credit risk in commercial bank did not increase income and reduce risk. Because commercial Banks can extend more bad loans to expand its lending scale, and bad loans will increase the bank overall risk. 展开更多
关键词 Commercial banks credit risk transfer panel data PERFORMANCE
下载PDF
风险管理联合精准护理在体外受精-胚胎移植中的应用效果研究
10
作者 夏凌 孟瑶 李进娥 《联勤军事医学》 CAS 2024年第7期614-618,共5页
目的 观察风险管理联合精准护理在体外受精-胚胎移植(in vitro fertilization-embryo transfer,IVF-ET)患者中的应用效果。方法 回顾性分析2022-01/2023-12月在作者医院行IVF-ET治疗的98例不孕症患者,按照不同的护理管理方法分为管理组... 目的 观察风险管理联合精准护理在体外受精-胚胎移植(in vitro fertilization-embryo transfer,IVF-ET)患者中的应用效果。方法 回顾性分析2022-01/2023-12月在作者医院行IVF-ET治疗的98例不孕症患者,按照不同的护理管理方法分为管理组和对照组,每组各49例。对照组不孕症患者采用IVF-ET后常规护理措施;管理组不孕症患者采用IVF-ET后风险管理联合精准护理措施。比较两组不孕症患者的健康宣教知识知晓度评分、患者依从性评分、护理安全风险事件发生率和护理满意度。鲜胚移植术后随访,比较两组不孕症患者睡眠及妊娠情况。结果 管理组不孕症患者健康宣教知识知晓度评分、患者依从性评分均优于对照组,差异具有统计学意义(P均<0.05)。管理组不孕症患者的护理安全风险事件总发生率低于对照组,满意度高于对照组,差异有统计学意义(P均<0.05)。促排卵启动日两组不孕症患者阿森斯失眠量表(Athens insomnia scale,AIS)评分比较差异无统计学意义(P>0.05),鲜胚移植术后4周管理组不孕症患者AIS评分低于对照组,差异有统计学意义(P<0.05)。两组不孕症患者获卵数比较差异无统计学意义(P>0.05),管理组不孕症患者临床妊娠率高于对照组,差异有统计学意义(P<0.05)。结论 风险管理联合精准护理能提升不孕症患者对健康宣教知识的知晓率,有效规避临床护理工作中潜在的风险隐患问题,进而降低护理不良事件的发生,改善患者对护理服务的满意度,同时可提高不孕症患者的睡眠质量和临床妊娠率。 展开更多
关键词 风险管理 精准护理 体外受精-胚胎移植 临床妊娠率 护理安全
下载PDF
United States Healthcare Data Breaches: Insights for NIST SP 800-66 Revision 2 from a Review of the NIST SP 800-66 Revision 1
11
作者 Mohammed Mohammed Raoof 《Journal of Information Security》 2024年第2期232-244,共13页
Healthcare security and privacy breaches are occurring in the United States (US), and increased substantially during the pandemic. This paper reviews the National Institute of Standards and Technology (NIST) publicati... Healthcare security and privacy breaches are occurring in the United States (US), and increased substantially during the pandemic. This paper reviews the National Institute of Standards and Technology (NIST) publication base as an effective solution. The NIST Special Publication 800-66 Revision 1 was an essential standard in US healthcare, which was withdrawn in February 2024 and superseded by SP 800-66 Revision 2. This review investigates the academic papers concerning the application of the NIST SP 800-66 Revision 1 standard in the US healthcare literature. A systematic review method was used in this study to determine current knowledge gaps of the SP 800-66 Revision 1. Some limitations were employed in the search to enforce validity. A total of eleven articles were found eligible for the study. Consequently, this study suggests the necessity for additional academic papers pertaining to SP 800-66 Revision 2 in the US healthcare literature. In turn, it will enhance awareness of safeguarding electronic protected health information (ePHI), help to mitigate potential future risks, and eventually reduce breaches. 展开更多
关键词 SP 800-66 Revision 1 SP 800-66 Revision 2 HIPAA Compliance Security Breaches risk Management Framework (RMF) Internet of Things (IoT) Artificial Intelligence (AI)
下载PDF
基于SFN-SD的北极冰区船舶航行风险传递路径研究 被引量:1
12
作者 席永涛 张靓 +2 位作者 付姗姗 胡甚平 韩冰 《中国安全科学学报》 CAS CSCD 北大核心 2023年第4期52-60,共9页
为明晰北极冰区船舶航行风险传递路径,从人员、船舶、环境、管理4方面识别北极冰区航行风险因素,并应用空间故障网络(SFN)理论和决策试验与评估实验室(DEMATEL)方法,分析船舶北极航行风险事件;采用主观数据获得风险传递概率和传递路径,... 为明晰北极冰区船舶航行风险传递路径,从人员、船舶、环境、管理4方面识别北极冰区航行风险因素,并应用空间故障网络(SFN)理论和决策试验与评估实验室(DEMATEL)方法,分析船舶北极航行风险事件;采用主观数据获得风险传递概率和传递路径,构建北极冰区船舶航行风险传递网络模型;基于永盛轮北极航行记录数据,运用系统动力学(SD)方法,仿真并验证北极冰区船舶航行风险传递网络模型。结果表明:船舶北极航行风险事件中,8种为边缘事件,14种为过程事件,8种为最终事件;从边缘事件到最终事件有15条网络传递路径;经实例验证,所构建的风险传递网络模型可靠;通过该模型能够描述风险事件的传递效应和传递路径,获得最终风险事件的动态概率曲线,揭示北极冰区船舶航行风险传递的规律,为风险防范措施的制定提供技术支持。 展开更多
关键词 空间故障网络(SFN) 系统动力学(SD) 北极冰区 船舶航行风险 传递网络
下载PDF
Evolution trend of the water quality in Dongping Lake after South-North Water Transfer Project in China 被引量:2
13
作者 HU Zun-fang KANG Feng-xin +4 位作者 ZOU An-de YU Lin-song LI Yang TIAN Tong-liang KANG Gui-ling 《Journal of Groundwater Science and Engineering》 2019年第4期333-339,共7页
To investigate the evolution trend of water quality in Dongping Lake after South-North Water Transfer Project operation as well as to ensure the safe usage of the water receiving areas, water samples were collected an... To investigate the evolution trend of water quality in Dongping Lake after South-North Water Transfer Project operation as well as to ensure the safe usage of the water receiving areas, water samples were collected and determined before and after water delivery in different hydrological seasons. Then, comprehensive pollution index method, comprehensive nutrition state index method and health risk assessment model were utilized to evaluate the quality, nutrition, and health risk of Dongping Lake water. Results showed that the quality of Dongping Lake water still met level Ⅲ (light pollution) no matter before or after water delivery. The nutrition state was improved from light eutropher before water delivery to mesotropher after water delivery. The health risk level was reduced from high-medium before water delivery to medium level after water delivery. In summary, the operation of the eastern route of South-North Water Transfer Project is beneficial for water environment improvement of Dongping Lake. 展开更多
关键词 South-North WATER transfer Project Dongping LAKE WATER quality NUTRITION Health risk
下载PDF
Activity of the Fungicide JS399-19 Against Fusarium Head Blight of Wheat and the Risk of Resistance 被引量:7
14
作者 CHEN Yu WANG Wen-xiang +3 位作者 ZHANG Ai-fang GU Chun-yan ZHOU Ming-guo GAO Tong-chun 《Agricultural Sciences in China》 CAS CSCD 2011年第12期1906-1913,共8页
This report reviews the characteristics of JS399-19, a novel cyanoacrylate fungicide. JS399-19 strongly inhibits the mycelial growth of the fungal plant pathogens of the genus Fusarium and exhibits great potential in ... This report reviews the characteristics of JS399-19, a novel cyanoacrylate fungicide. JS399-19 strongly inhibits the mycelial growth of the fungal plant pathogens of the genus Fusarium and exhibits great potential in controlling Fusarium head blight (FHB) on wheat and other cereals. The mode of action of JS399-19 is evidently different from that of benzimidazole (for example, carbendazim) and other sort of fungicides, making it a possible replacement for carbendazim in China to manage carbendazim-resistant subpopulations of Fusarium graminearum and F. asiaticum. JS399-t9 has excellent protective and curative activity against these pathogens. Incorrect use of this fungicide, however, is likely to select for resistance. Among JS399-19-resistant mutants of F. asiaticum induced in the laboratory, the resistant level of mutants was high and the phenotype of resistance against JS399-19 was conferred by a major gene by genetic analysis. The fitness of laboratory-induced JS399-19-resistant mutants of F. asiaticum was nearly equal to that of their parents. JS399-19 lacks cross resistance with other sort fungicides. To control FHB with JS399-19 and to delay the development of the fungicide-resistance, farmers should use tank mixtures containing JS399-19 and carbendazim, metconazole, tebuconazole, or prothioconazole. 展开更多
关键词 fungicide JS399-19 cyanoacrylate fungicide Fusarium head blight ACTIVITY resistance risk
下载PDF
Interfacial stress transfer behavior in a specially-shaped fiber/matrix pullout test 被引量:2
15
作者 Y. R. Zhao Y. M. Xing +1 位作者 Z. K. Lei F. C. Lang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第1期113-119,共7页
Specially designed fibers are widely used in engineering practice because the specially-designed shape can help to improve the bonding strength of the fiber and the interface. Studied in this paper is the interfacial ... Specially designed fibers are widely used in engineering practice because the specially-designed shape can help to improve the bonding strength of the fiber and the interface. Studied in this paper is the interfacial shear stress transfer behavior on both sides of the specially designed fiber when it is being pulled out; in which automatic analysis of three-dimensional photoelasticity is employed and the finite element method is adopted. The results show that the stress transfer occurs mainly in the region near the fiber's embedded end where the stress reaches its critical point, leading to debonding of the interface. Before debonding, as the pullout loading increases, the peak value of shear stress transfers along the fiber from the embedded end to the interior of the matrix, and then stops at the hooked part of the fiber because of its impediment. When the interface begins to debond as the load increases, the shear stress can be transferred to the hooked part. 展开更多
关键词 Fiber-reinforced composites Specially-shaped fiber Interfacial stress transfer Photo-elasticity - FEM
下载PDF
基于水-光-荷模块分层协同搜索的风险调度策略 被引量:5
16
作者 鲜于虎成 黄显峰 +3 位作者 李旭 李大成 张艳青 许昌 《电网技术》 EI CSCD 北大核心 2023年第3期908-917,共10页
多能互补是促进清洁能源并网消纳与提升电力调节性能的重要途径,多源接入规模加剧了决策与风险并存问题。该文旨在优化搜索维度,协调源–荷互动关系以应对能源消纳与调峰压力,并保障电站与机组运行可靠性。为此提出光–荷模块分层协同... 多能互补是促进清洁能源并网消纳与提升电力调节性能的重要途径,多源接入规模加剧了决策与风险并存问题。该文旨在优化搜索维度,协调源–荷互动关系以应对能源消纳与调峰压力,并保障电站与机组运行可靠性。为此提出光–荷模块分层协同搜索策略。在外层,提出光–荷预测偏差的鲁棒特征,依据场景集合反演特征参数,计及光–荷模块多重不确定性的置信区间;在中层,结合源–荷调节平衡能力重构水–光模块,旨在支持系统出力调峰目标;在内层,引入中层电力重构的电量与波动特征识别机组运行风险区间,通过逐步优化机组安排与分区负荷转移,降低机组穿越振动区风险;以此建立层间目标跟踪与层内风险调控的动态协同搜索策略,形成光–荷不确定性下的发电决策空间。最后以澜沧江西藏段混合发电系统为研究背景,结果表明该策略相较于传统方法,在响应调峰目标的基础上有效降低了光、荷交替波动下的系统运行风险。 展开更多
关键词 多能互补 消纳 调峰 模块重构 风险识别 负荷转移 优化调度
下载PDF
Kinetic Study of Atom Transfer Radical Polymerization of 2-(N,N-Dimethylamino)ethyl Methacrylate 被引量:2
17
作者 江成发 张允湘 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第2期208-213,共6页
A kinetic model was developed to describe the atom transfer radical polymerization (ATRP) of 2(N,N-dimethylarnino) ethyl methacrylate (DMAEMA). The model was based on a polymerization mechanism, which included the ato... A kinetic model was developed to describe the atom transfer radical polymerization (ATRP) of 2(N,N-dimethylarnino) ethyl methacrylate (DMAEMA). The model was based on a polymerization mechanism, which included the atom transfer equilibrium for primary radical, the propagation of growing polymer radical, and the atom transfer equilibrium for the growing polymer radical. An experiment was carried out to measure the conversion of monomer, the number-average molecular weight of polymer and molecular weight distribution for the ATRP process of DMAEMA. The experimental data were used to correlate the kinetic model and rate constants were obtained. The rate constants of activation and deactivation in the atom transfer equilibrium for primary radical are 1.0 x 10(4) L(.)mol(-1.)s(-1) and 0.04 L(.)mol(-1.)s(-1), respectively. The rate constant of the propagation of growing polymer radical is 8.50 L(.)mol(-1.)s(-1), and the rate constants of activation and deactivation in the atom transfer equilibrium for growing polymer radical are 0.045 L(.)mol(-1.)s(-1) and 1.2 x 10(5) L(.)mol(-1.)s(-1), respectively. The values of the rate constants represent the features of the ATRP process. The kinetic model was used to calculate the ATRP process of DMAEMA. The results show that the calculations agree well with the measurements. 展开更多
关键词 KINETICS MODELING atom transfer radical polymerization moment method 2-(N N-dimethylamino)-ethyl methacrylate
下载PDF
Synthesis and characterization of Ca2Sn1-xCexO4 with blue luminescence originating from Ce^4+ charge transfer transition 被引量:1
18
作者 符史流 尹涛 柴飞 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第10期3129-3133,共5页
Ce^4+-doped Ca2SnO4 with a one-dimensional structure, which emits bright blue light, is prepared by using a solid-state reaction method. The x-ray diffraction results show that the Ce^4+ ions doped in Ca2SnO4 occupy... Ce^4+-doped Ca2SnO4 with a one-dimensional structure, which emits bright blue light, is prepared by using a solid-state reaction method. The x-ray diffraction results show that the Ce^4+ ions doped in Ca2SnO4 occupy the Sn^4+ sites. The excitation and emission spectra of Ca2Sn1-xCexO4 appear to have broad bands with peaks at - 268nm and -442nm, respectively. A long excited-state lifetime (-83μs) for the emission from Ca2Sn1-xCexO4 suggests that the luminescence originates from a ligand-to-metal Ce^4+ charge transfer (CT). The luminescent properties of Ca2Snl_xCexO4 have been compared with those of Sr2CeO4, which is the only material reported so far to show Ce^4+ CT luminescence. More interestingly, it is observed that the emission intensity of Ca2Sn1-xCexO4 with a small doping concentration (x - 0.03) is comparable to that of Sr2CeO4 in which the concentration of active centre is 100%. 展开更多
关键词 Ca2Sn1-xCexO4 Ce^4+-O^2- charge transfer luminescent property
下载PDF
Risk Assessment M ode of Sale-Leaseback——Based on Fuzzy Analytic Hierarchy Process 被引量:1
19
作者 陈俊宇 李智 张佳煌 《Journal of Donghua University(English Edition)》 EI CAS 2013年第4期343-348,共6页
Sale-leaseback is paid special focus on for its great application in China in recent years.By giving a detailed analysis,an analysis of the features of sale-leaseback and a study of the risks of it are given in this p... Sale-leaseback is paid special focus on for its great application in China in recent years.By giving a detailed analysis,an analysis of the features of sale-leaseback and a study of the risks of it are given in this paper.Then a quantitative analysis of commercial real estate sale-leaseback is carried out.The scientific theoretical analysis is provided in this paper for risk assessment in commercial real estate sale-leaseback mode in China.An effective approach is put forward for sale-leaseback project evaluation and prevention of risk.A useful means is given to supervise commerciai real estate sale-leaseback mode for relevant departments and a certain contribution is made to a further sound development of commercial real estate sale-leaseback mode. 展开更多
关键词 sale-leaseback fuzzy analytic hierarchy process(FAHP) risk assessment modeCLC number:F830.9Document code:AArticle ID:1672-5220(2013)04-0343-06
下载PDF
Optimization of the Classic Transfer-Stacking Model Migration Algorithm: A Way to Solve Time-Varying Performance Degradation of Acute Kidney Injury Clinical Prediction Model
20
作者 Yunfei Xue 《Journal of Biosciences and Medicines》 2021年第4期14-28,共15页
Acute Kidney Injury (AKI) is one of the most common acute and critical illnesses in general wards and intensive care units. Its high morbidity and high fatality rate have become a major global public health problem. T... Acute Kidney Injury (AKI) is one of the most common acute and critical illnesses in general wards and intensive care units. Its high morbidity and high fatality rate have become a major global public health problem. There are often serious lags in clinical diagnosis of AKI. Early diagnosis and timely intervention and effective care become critical. The use of electronic medical record data to build an AKI risk prediction model has been proven to help prevent the occurrence of AKI. However, in actual clinical applications, the distribution of historical data and new data will continue to vary over time, resulting in a significant decrease in the performance of the model. How to solve the problem of model performance degradation over time will be a core challenge for the long-term use of predictive models in clinical applications. Aiming at the above problems, this paper studies the classic Transfer-Stacking model migration algorithm. Aiming at the lack of this algorithm, such as the loss of a large amount of feature information of the target domain and poor fit when integrating the model of the target domain, the Accumulate-Transfer-Stacking algorithm is proposed to improve it. Improvements include: 1) Optimize the input vector and model integration algorithm of Transfer-Stacking’s target domain model. 2) Optimize Transfer-Stacking from a single-source domain model to a multi-source domain model. The experimental results show that for the improved algorithm proposed in this paper when the data is sufficient and insufficient, the average AUC value of the model on the data of subsequent years is 0.89 and 0.87, and the average F1 Score value is 0.45 and 0.36. Moreover, this method is significantly better than the unimproved Transfer-Stacking algorithm and baseline method, and can effectively overcome the problem of data distribution heterogeneity caused by time factors. 展开更多
关键词 Acute Kidney Injury Electronic Medical Record risk Prediction transfer Learning
下载PDF
上一页 1 2 58 下一页 到第
使用帮助 返回顶部