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Tsinghua University Appoints 28 Overseas Scholars
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《Tsinghua Science and Technology》 SCIE EI CAS 2002年第6期635-635,共1页
关键词 Tsinghua University appoints 28 Overseas Scholars WELL
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LANXESS Appoints GM of Specialty Chemicals Company Shanghai
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《China Chemical Reporter》 2009年第10期8-8,共6页
LANXESS AG has appointed Natalie Chen asGeneral Manager of LANXESS Specialty ChemicalsCompany Limited, Jinshan, Shanghai.The company is a legal entity newly establishedin September 2008 following the successfulacquisi... LANXESS AG has appointed Natalie Chen asGeneral Manager of LANXESS Specialty ChemicalsCompany Limited, Jinshan, Shanghai.The company is a legal entity newly establishedin September 2008 following the successfulacquisition of the plant in Jinshan-the largestand most modem plant for yellow iron oxide pigmentsin China. It is a 100% subsidiary ofLANXESS Shanghai Pigments CompanyLimited. 展开更多
关键词 SUBSIDIARY appointed LEGAL MODEM QUARTERS YELLOW f
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CNOOC Ltd.Appoints New CEO
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《China Chemical Reporter》 2010年第17期6-6,共11页
CNOOC Ltd.announces it has appointed Mr.Yang Hua as its new Chief Executive Officer andnew Vice Chairman of the Board, effective September16th, 2010.Mr.Yang will resign fromthe role of President and Chief Financial Of... CNOOC Ltd.announces it has appointed Mr.Yang Hua as its new Chief Executive Officer andnew Vice Chairman of the Board, effective September16th, 2010.Mr.Yang will resign fromthe role of President and Chief Financial Officerof the company.Also, CNOOC Ltd.appointsMr.Li Fanrong as new President. 展开更多
关键词 appointed Chairman Officer ANALYST SEEKING
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Comprehensive characterization of volatile organic compounds in Chinese chemical industry park soils:Spatial variation,source identification,and health risk assessment 被引量:1
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作者 Haibao Zhu Yuanchen Chen +3 位作者 Zheng Ruan Han Wang Danhua Liu Meirong Zhao 《Journal of Environmental Sciences》 2025年第9期48-59,共12页
Ubiquitous contamination of the soil environment with volatile organic compounds(VOCs)has raised considerable concerns.However,there is still limited comprehensive surveying of soil VOCs on a national scale.Herein,65 ... Ubiquitous contamination of the soil environment with volatile organic compounds(VOCs)has raised considerable concerns.However,there is still limited comprehensive surveying of soil VOCs on a national scale.Herein,65 species of VOCswere simultaneously determined in surface soil samples collected from 63 chemical industrial parks(CIPs)across China.The results showed that the total VOC concentrations ranged from 7.15 to 1842 ng/g with a mean concentration of 326 ng/g(median:179 ng/g).Benzene homologs and halogenated hydrocarbons were identified as the dominant contaminant groups.Positive correlations between many VOC species indicated that these compounds probably originated from similar sources.Spatially,the hotspots of VOC pollution were located in eastern and southern China.Soils with higher clay content and a higher fraction of total organic carbon(TOC)content were significantly associated with higher soil VOC concentrations.Precipitation reduces the levels of highly water-soluble substances in surface soils.Both positive matrix factorization(PMF)and principal component analysis-multiple linear regression(PCA-MLR)identified a high proportion of industrial sources(PMF:59.2%and PCA-MLR:66.5%)and traffic emission sources(PMF:32.3%and PCA-MLR:33.5%).PMF,which had a higher R^(2) value(0.7892)than PCA-MLR(0.7683),was the preferred model for quantitative source analysis of soil VOCs.The health risk assessment indicated that the non-carcinogenic and carcinogenic risks of VOCs were at acceptable levels.Overall,this study provides valuable data on the occurrence of VOCs in soil from Chinese CIPs,which is essential for a comprehensive understanding of their environmental behavior. 展开更多
关键词 Volatile organic compounds Chemical industry park soils Source appointment Risk assessment
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A Smartphone Is Not Enough:Telehealth Attendance and the Digital Divide
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作者 James Labadorf Matthew Nichols +2 位作者 Tayana Williams Celina Cunanan Brian D'Anza 《Health Care Science》 2025年第4期259-268,共10页
Background:Telehealth has emerged as a powerful tool for managing chronic diseases and mental health conditions,offering increased access to care and improved patient outcomes.However,inequities in digital connectivit... Background:Telehealth has emerged as a powerful tool for managing chronic diseases and mental health conditions,offering increased access to care and improved patient outcomes.However,inequities in digital connectivity and technological resources have created significant disparities in access to these potentially life-changing services,disproportionately impacting marginalized and minoritized communities across the globe.Methods:Data on 473,716 telehealth encounters occurring between January 1,2022,and June 30,2023 were retrieved from the electronic health records(EHR)system used by University Hospitals.These encounters were classified into three groups:attended,canceled,and no-show.Relative risk was calculated based on age,sex,and race,and a multivariate linear regression was performed with age,sex,and race as inputs,to determine their effect on the encounter outcome.Results:Our analysis identified significant differences in relative risk between demographic groups.Patients 20-39 years of age had a high relative risk of cancellation and no-show,and Black patients demonstrated the highest relative risk for cancellation and no-show.The regression analysis illustrated a statistically significant link between no-shows and patients with a cellular plan with no other internet subscription(p<0.001),smartphone ownership(p<0.001),and not having a computer(p<0.05).Conclusions:This study highlights the clinical repercussions of the digital divide,as patients relying on a mobile phone and data plan to attend telehealth visits were more likely to no-show.Current disparities in digital connectivity for historically marginalized populations heightens the risk of creating a digital underclass.There is evidence this study may be applicable in multiple countries across the world.Further research on the causes of the observed no-shows is necessary to ensure equitable delivery of digital healthcare services. 展开更多
关键词 appointment cancellations data plan digital divide digital health healthcare access missed appointment no-show SMARTPHONE TELEHEALTH virtual care
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The Implementation Dilemmas and Solutions of the Appointed Guardianship System from the Perspective of the Protection of the Rights and Interests of the Elderly
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作者 LI Dejian ZHENG Ran JIANG Yu(Translated) 《The Journal of Human Rights》 2025年第4期896-917,共22页
In a deeply aging society,the appointed guardianship system,as an important arrangement for the protection of the rights and interests of the elderly,still faces many practical difficulties.Typical examples include:du... In a deeply aging society,the appointed guardianship system,as an important arrangement for the protection of the rights and interests of the elderly,still faces many practical difficulties.Typical examples include:during the decision-making stage of whether to choose appointed guardianship,the lack of professionalism and availability of appointed guardians can easily hinder the elderly from choosing to apply it;during the establishment stage of appointed guardianship,the limited rules related to the appointed guardianship agreement can easily lead to the frustration of the elderly’s subjective will;during the operation stage of appointed guardianship,the insufficient accountability mechanisms for appointed guardians can easily lead to the infringement of the personal or property rights of the elderly.By reflecting on its jurisprudential causes,it can be found that the current law largely ignores the orientation of appointed guardianship as a welfare for the elderly in social law,the concept of substantive equality in the appointed guardianship agreement,and the theoretical attributes of the appointed guardianship as a fiduciary relationship.Therefore,the appointed guardianship system in China should be systematically improved to fully release its institutional potential in the protection of the rights and interests of the elderly based on these jurisprudential principles.In particular,it is possible to consider actively promoting the“trust+appointed guardianship”model and cultivating a team of appointed guardians by the state based on the concept of elderly welfare;strengthening the protection of notarization procedures and the reasonable design of the appointed guardianship agreement based on the concept of substantive equality;and refining the fiduciary standards of appointed guardians and strengthening guardianship supervision based on the nature of fiduciary relationship. 展开更多
关键词 protection of the rights and interests of the elderly appointed guardianship elderly welfare substantive equality fiduciary relationship
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老年患者门诊预约挂号的影响因素:基于安德森健康行为模型的实证研究 被引量:10
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作者 朱慧敏 刘隽 +3 位作者 李钟仁 张薇琪 张文珊 孙振军 《中国卫生资源》 CSCD 北大核心 2023年第3期286-292,共7页
目的基于安德森健康行为模型,研究老年患者门诊预约挂号的影响因素,为优化门诊预约挂号服务、推进老年患者预约挂号提供参考。方法以安德森健康行为模型为理论框架设计问卷,采用方便抽样法向上海某三级甲等综合医院门诊老年患者发放调... 目的基于安德森健康行为模型,研究老年患者门诊预约挂号的影响因素,为优化门诊预约挂号服务、推进老年患者预约挂号提供参考。方法以安德森健康行为模型为理论框架设计问卷,采用方便抽样法向上海某三级甲等综合医院门诊老年患者发放调查问卷。将各维度因素纳入二分类logistic回归模型,采用单因素分析和logistic回归分析探讨老年患者门诊预约挂号的影响因素。结果共回收282份有效问卷,预约挂号187人,占66.31%。曾使用过1~2种预约挂号服务、存在社会支持、距离医院路程80 min以上、收入为>5000~7500元、就诊科室预约率25.00%以上、有预约挂号使用意愿的老年患者更倾向于预约挂号。患慢性病数量在5种及以上的老年患者更不倾向于预约挂号。结论老年患者门诊预约需求较大且受多种因素影响。须关注老年人预约挂号“痛点”,关怀老年群体,共建支持网络,加强有效宣传,优化医疗资源配置,激发使用意愿。 展开更多
关键词 老年患者elderly patient 门诊预约挂号outpatient appointment registration 安德森健康行为模型Anderson’s health behavior model 影响因素influencing factor
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上海市预防接种网约服务发展历程、现状、问题与策略 被引量:13
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作者 刘捷宸 马晓英 +5 位作者 胡家瑜 黄卓英 杨守飞 任佳 吴琳琳 孙晓冬 《中国卫生资源》 北大核心 2022年第2期150-153,共4页
回顾上海市预防接种网络预约接种服务(以下简称“网约服务”)的发展历程,成绩斐然,网约服务方便接种门诊规划工作,方便受种者,特定疫苗预约功能方便紧缺疫苗管理和接种、助力完成新型冠状病毒疫苗接种。针对已建成的上海市预防接种网约... 回顾上海市预防接种网络预约接种服务(以下简称“网约服务”)的发展历程,成绩斐然,网约服务方便接种门诊规划工作,方便受种者,特定疫苗预约功能方便紧缺疫苗管理和接种、助力完成新型冠状病毒疫苗接种。针对已建成的上海市预防接种网约服务系统的局限性提出改进建议方案,旨在未来进一步优化上海市预防接种网约服务,提高疫苗接种可及性及用户服务满意度。 展开更多
关键词 预防接种vaccination 网络预约服务network appointment service 互联网+internet plus 上海市Shanghai
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Investigation of PM_(2.5) pollution during COVID-19 pandemic in Guangzhou,China 被引量:6
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作者 Luyao Wen Chun Yang +9 位作者 Xiaoliang Liao Yanhao Zhang Xuyang Chai Wenjun Gao Shulin Guo Yinglei Bi Suk-Ying Tsang Zhi-Feng Chen Zenghua Qi Zongwei Cai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2022年第5期443-452,共10页
The COVID-19 pandemic has raised awareness about various environmental issues,includ-ing PM_(2.5) pollution.Here,PM_(2.5) pollution during the COVID-19 lockdown was traced and an-alyzed to clarify the sources and fact... The COVID-19 pandemic has raised awareness about various environmental issues,includ-ing PM_(2.5) pollution.Here,PM_(2.5) pollution during the COVID-19 lockdown was traced and an-alyzed to clarify the sources and factors influencing PM_(2.5) in Guangzhou,with an emphasis on heavy pollution.The lockdown led to large reductions in industrial and traffic emissions,which significantly reduced PM_(2.5) concentrations in Guangzhou.Interestingly,the trend of PM_(2.5) concentrations was not consistent with traffic and industrial emissions,as minimum concentrations were observed in the fourth period(3/01-3/31,22.45 μg/m^(3))of the lockdown.However,the concentrations of other gaseous pollutants,e.g.,SO_(2),NO_(2) and CO,were corre-lated with industrial and traffic emissions,and the lowest values were noticed in the sec-ond period(1/24-2/0_(3))of the lockdown.Meteorological correlation analysis revealed that the decreased PM_(2.5) concentrations during COVID-19 can be mainly attributed to decreased in-dustrial and traffic emissions rather than meteorological conditions.When meteorological factors were included in the PM_(2.5) composition and backward trajectory analyses,we found that long-distance transportation and secondary pollution offset the reduction of primary emissions in the second and third stages of the pandemic.Notably,industrial PM_(2.5) emis-sions from western,southern and southeastern Guangzhou play an important role in the formation of heavy pollution events.Our results not only verify the importance of control-ling traffic and industrial emissions,but also provide targets for further improvements in PM_(2.5) pollution. 展开更多
关键词 PM_(2.5)pollution COVID-19 pandemic PM_(2.5)composition Meteorological analysis Source appointment
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Sources appointment and health risks of PM_(2.5)-bound trace elements in a coastal city of southeastern China 被引量:5
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作者 Ziyi Lin Xiaolong Fan +8 位作者 Gaojie Chen Youwei Hong Mengren Li Lingling Xu Baoye Hu Chen Yang Yanting Chen Zhiqian Shao Jinsheng Chen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第4期561-571,共11页
To gain a comprehensive understanding of sources and health risks of trace elements in an area of China with high population densities and low PM_(2.5)concentrations,15 trace elements(Al,K,Ca,Ti,V,Cr,Mn,Fe,Ni,Cu,Zn,As... To gain a comprehensive understanding of sources and health risks of trace elements in an area of China with high population densities and low PM_(2.5)concentrations,15 trace elements(Al,K,Ca,Ti,V,Cr,Mn,Fe,Ni,Cu,Zn,As,Sn,Ba,Pb)in PM_(2.5)were monitored from December 2020 to November 2021 in a representative city,Xiamen.The concentrations of trace elements in Xiamen displayed an obvious seasonal variation and were dominated by K,Fe,Al,Ca and Zn.Based on Positive Matrix Factorization analysis,source appointment revealed that the major sources of trace elements in Xiamen were traffic,dust,biomass and firework combustion,industrial manufacture and shipping emission.According to health risk assessment combined with the source appointment results,it indicated that the average noncarcinogenic risk was below the threshold and cancer risk of four hazardous metals(Cr,Ni,As,Pb)exceeded the threshold(10^(-6)).Traffic-related source had almost half amount of contribution to the health risk induced by PM_(2.5)-bound trace elements.During the dust transport period or Spring Festival period,the health risks exceeded an acceptable threshold even an order of magnitude higher,suggesting that the serious health risks still existed in low PM_(2.5)environment at certain times.Health risk assessment reminded that the health risk reduction in PM_(2.5)at southeastern China should prioritize traffic-related hazardous trace elements and highlighted the importance of controlling vehicles emissions in the future. 展开更多
关键词 PM_(2.5)-bound trace elements Seasonal variations Source appointment Health risks Traffic-related source
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Appointment scheduling with customer impatience based on operating cost model 被引量:1
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作者 Song Minshan Zhang Yulin 《Journal of Southeast University(English Edition)》 EI CAS 2019年第2期252-256,共5页
An appointment scheduling problem is studied with the consideration of customer impatience.On the assumption that both the time of leaving queue and the time of service are exponentially distributed,in order to minimi... An appointment scheduling problem is studied with the consideration of customer impatience.On the assumption that both the time of leaving queue and the time of service are exponentially distributed,in order to minimize the joint cost,the optimal appointment schedule of the fixed number of customers is studied.The joint cost function is composed of customers expected delay time and service availability time.The expected delay time of each customer in the queue is recursively computed in terms of customer interarrival time.Furthermore,the effect of impatience on the optimal schedule as well as the total operating cost is studied.The results show that as the impatience rate increases,the optimal interarrival time becomes shorter and the interarrival time of the last few customers gradually approaches that of the customers in the middle.In addition,impatient behaviors can increase the joint cost. 展开更多
关键词 APPOINTMENT customer impatience queueing theory single server
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Lessons from the Real World: Financial Incentives to Improve Glycemic Control in Patients with Type 2 Diabetes 被引量:1
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作者 June F. O’Leary Janelle Howe +1 位作者 Jeremy Rich Glenn Melnick 《Health》 2018年第2期171-180,共10页
Objectives: While the value of glycemic control to minimize adverse health outcomes among patients with diabetes is clear, achieving hemoglobin A1c (A1c) goals remain a challenge. We evaluated the use of financial inc... Objectives: While the value of glycemic control to minimize adverse health outcomes among patients with diabetes is clear, achieving hemoglobin A1c (A1c) goals remain a challenge. We evaluated the use of financial incentives to increase enrollment and improve glycemic control among patients invited to participate in a monthly diabetes group appointment (DGA) as part of their enrollment in DaVita HealthCare Partners, a large southern California managed care organization. Methods: Adult diabetes patients (≥18 years) with a currently uncontrolled hemoglobin A1c level (>8.0% if 9.0% if ≥ 65 years) were randomized to 1) no DGA, 2) DGA with no financial incentives (non-incentive DGA) or 3) DGA with financial incentives (incentive DGA). Results: Nine sites among four regions of the greater Los Angeles area participated. Each site offered one non-incentive DGA and one incentive DGA. Over 1500 patients were identified for recruitment and at the peak of enrollment, 299 patients were enrolled in 18 DGAs. On average, hemoglobin A1c values dropped more for patients participating in the incentive DGA (9.9% to 8.7%, -1.2%) versus non-incentive DGA (9.7% to 9.0%, -0.7%) versus no DGA group (9.1% to 8.7%, -0.4%). Several unexpected implementation challenges arose which complicated evaluation but provide important learning lessons. Conclusions: Management of chronic diseases like diabetes is challenging for patients and the primary care system alike. Continuing to implement and evaluate programs under “real-world” conditions can provide further insight into how best to support patients with diabetes and their primary care teams in order to achieve glycemic control and avoid preventable complications. 展开更多
关键词 DIABETES Glycemic Control FINANCIAL INCENTIVES BEHAVIORAL ECONOMICS Group Appointments
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形容词位置不同对其意义的影响
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作者 刘建辉 杨述伊 《白城师范高等专科学校学报》 2001年第3期56-58,共3页
大多数形容词,具有三种主要用法:作前置定语、后置定语和表语。一般来说,作前置定语的形容词表示限制意义,作后置定语或表语的形容词表示描绘意义,有时同一个形容词在不同的位置上具有不同的词义。本文试结合一些常见的形容词来说明其... 大多数形容词,具有三种主要用法:作前置定语、后置定语和表语。一般来说,作前置定语的形容词表示限制意义,作后置定语或表语的形容词表示描绘意义,有时同一个形容词在不同的位置上具有不同的词义。本文试结合一些常见的形容词来说明其位置对意义的影响。 1.alive (1)作前置定语时作“active,fuul of life” 展开更多
关键词 前置定语 ALIVE 英国英语 暗指 女口 天才作家 医院病 活着 ORGANIZER appointed
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Applications of Artificial Intelligence in Morocco’s Healthcare Sector: A Springboard to Medical Excellence 被引量:1
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作者 Chaimaa Idaomar Dahbia Idaomar +1 位作者 Mouna Hannaoui Khalid Chafik 《Journal of Computer and Communications》 2024年第9期63-77,共15页
Artificial intelligence (AI) is revolutionizing the healthcare sector worldwide. In Morocco, several AI applications are being deployed in public and private healthcare establishments, improving appointment management... Artificial intelligence (AI) is revolutionizing the healthcare sector worldwide. In Morocco, several AI applications are being deployed in public and private healthcare establishments, improving appointment management, surgical operations, diagnostics, patient record tracking, biology and radiology, and OR organization. This article explores the main AI applications used in the Moroccan healthcare sector, their frequency of use, the types of establishments adopting them, as well as the main functionalities of each application and its contribution to the sector. The aim of this study is to analyze the impact of the main AI applications on quality of care and process efficiency in Moroccan healthcare facilities. This research focuses on several fundamental questions: Which AI applications are most frequently used? What types of establishments are adopting these technologies, and for which specific functionalities? What are the benefits and challenges of integrating AI into the Moroccan healthcare system, particularly in terms of territorial distribution and accessibility? The methodology is based on a quantitative analysis of data collected from selected healthcare establishments, combined with studies of reports from public health authorities and a sweep of their websites. The results show that 45% of hospitals use AI systems for appointment scheduling and 30% for medical diagnosis. The use of surgical robots, such as the Da Vinci system, increased by 30% between 2020 and 2024. Comparisons with other emerging countries highlight Morocco’s acceptable advances, while underlining the challenges, particularly in terms of the territorial distribution of these technological infrastructures generally centralized in the country’s major cities. 展开更多
关键词 Artificial Intelligence Public Health Appointments SURGERY DIAGNOSTICS Patient Records Biological and Radiological Analyses
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Prof. James M.Tiedje Appointed as an Honorary Editor-in-Chief
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《Pedosphere》 SCIE CAS CSCD 2019年第1期81-81,共1页
Prof.James M.Tiedje,University Distinguished Professor and Director of the Center for Microbial Ecology at Michigan State University,Academician of the American Academy of Sciences,has been appointed as an Honorary Ed... Prof.James M.Tiedje,University Distinguished Professor and Director of the Center for Microbial Ecology at Michigan State University,Academician of the American Academy of Sciences,has been appointed as an Honorary Editor-in-Chief of Pedosphere.Prof. 展开更多
关键词 JAMES M.Tiedje Appointed as an Honorary Editor-in-Chief
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Machine learning-based prediction models for patients no-show in online outpatient appointments 被引量:1
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作者 Guorui Fan Zhaohua Deng +1 位作者 Qing Ye Bin Wang 《Data Science and Management》 2021年第2期45-52,共8页
With the development of information and communication technologies,all public tertiary hospitals in China began to use online outpatient appointment systems.However,the phenomenon of patient no-shows in online outpati... With the development of information and communication technologies,all public tertiary hospitals in China began to use online outpatient appointment systems.However,the phenomenon of patient no-shows in online outpatient appointments is becoming more serious.The objective of this study is to design a prediction model for patient no-shows,thereby assisting hospitals in making relevant decisions,and reducing the probability of patient no-show behavior.We used 382,004 original online outpatient appointment records,and divided the data set into a training set(N_(1)=286,503),and a validation set(N_(2)=95,501).We used machine learning algorithms such as logistic regression,k-nearest neighbor(KNN),boosting,decision tree(DT),random forest(RF)and bagging to design prediction models for patient no-show in online outpatient appointments.The patient no-show rate of online outpatient appointment was 11.1%(N=42,224).From the validation set,bagging had the highest area under the ROC curve and AUC value,which was 0.990,followed by random forest and boosting models,which were 0.987 and 0.976,respectively.In contrast,compared with the previous prediction models,the area under ROC and AUC values of the logistic regression,decision tree,and k-nearest neighbors were lower at 0.597,0.499 and 0.843,respectively.This study demonstrates the possibility of using data from multiple sources to predict patient no-shows.The prediction model results can provide decision basis for hospitals to reduce medical resource waste,develop effective outpatient appointment policies,and optimize operations. 展开更多
关键词 Online health Online outpatient appointment Patient no-show Prediction model Machine learning
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Abundance and sources of particulate polycyclic aromatic hydrocarbons and aromatic acids at an urban site in central China
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作者 Luqi Shang Zhe Dong +4 位作者 Zihan Li Mingkai Wang Zihan Kong Xiao Li Ruiqin Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第8期155-168,共14页
We conducted a simultaneous field study of PM_(2.5)-bound particulate polycyclic aromatic hydrocarbons(PAHs)and aromatic acids(AAs)in a polluted city Zhengzhou to explore the concentration,sources and potential conver... We conducted a simultaneous field study of PM_(2.5)-bound particulate polycyclic aromatic hydrocarbons(PAHs)and aromatic acids(AAs)in a polluted city Zhengzhou to explore the concentration,sources and potential conversion pathways between PAHs and AAs in different seasons.The average concentrations of PM_(2.5),28PAHs and 8AAs during the sampling period were 77μg/m^(3),75 ng/m^(3),and 283 ng/m^(3),respectively.The concentration of both28PAHs and 8AAs were highest in winter and lowest in summer with ratios of 6.3 and 2.3,respectively.PAHs with 5-7 rings were the main components of PAHs(52%),followed by 4rings PAHs(30%)and 2-3 rings PAHs(18%).According to the source appointment results obtained by positive matrix factorization,the main sources of PAHs were combustion and vehicle emissions,which account for 37%and 34%,respectively.8AAs were divided into three groups,including four benzene dicarboxylic acids(B2CAs),three benzene tricarboxylic acids(B3CAs)and one benzene tetracarboxylic acid(B4CA).And interspecies correlation analysis with PM_(2.5)source markers were used to investigate potential sources.Phthalic acid(o-Ph)was the most abundant specie of 8AAs(157 ng/m^(3),55%of 8AAs),which was well correlated with sulfate.Meanwhile,B3CAs and B4CA were highly correlated with sulfate and weakly correlated with levoglucosan,suggesting that secondary formation was their main source.As logical oxidation products of PAHs,o-Ph and B3CAs showed good correlations with a number of PAHs,indicating possible photochemical oxidation pathway by PAHs.In addition,O_(3),NO_(2),temperature and relative humidity have positive effects on the secondary formation of B3CAs. 展开更多
关键词 Polycyclic aromatic hydrocarbons Aromatic acids Source appointment Secondary formation
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WORLD NEWS IN BRIEF(August 16-31, 1991)
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《国际展望》 北大核心 1991年第17期32-32,共1页
On August 19, Acting Soviet President Gennady Yanayev ordered a state of emergency in Moscow. Yansyev declared a six-month state of emergency in the Soviet Union. Minutes laten, the State Committee for the State of Em... On August 19, Acting Soviet President Gennady Yanayev ordered a state of emergency in Moscow. Yansyev declared a six-month state of emergency in the Soviet Union. Minutes laten, the State Committee for the State of Emergency was announcea to have been set up to govern the whole country. On August 22, Soviet President Mikhail Gorbachev appointed some new ministers after he was back in full control of the situation in the country. Criminal suits have been brought against all the members of 展开更多
关键词 appointed EMERGENCY MOSCOW laten govern NEWS ORDERED brought ORGANS easing
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Appointment of Dr. Xue-Long JIANG as the Associate Editor-in-Chief of Zoological Research
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《Zoological Research》 CAS CSCD 2016年第2期66-66,共1页
We are very pleased to announce that we have invited Dr. Xue-Long JIANG to serve as the Associate Editor-in-Chief for Zoological Research (ZR), effective from 1 March, 2016. Dr. JIANG, Professor and principle invest... We are very pleased to announce that we have invited Dr. Xue-Long JIANG to serve as the Associate Editor-in-Chief for Zoological Research (ZR), effective from 1 March, 2016. Dr. JIANG, Professor and principle investigator from the Laboratory of Mammal Ecology and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, has worked with ZR since 2006 as a member of the editorial board and has played an active and important role in maintaining ZR as a respected academic publishing platform. Currently, he also works as the Associate Editor-in-Chief of Acta Thefiologica Sinica, Mammal Research and as a senior editorial board member of Biodiversity Science. 展开更多
关键词 Appointment of Dr Xue-Long JIANG as the Associate Editor-in-Chief of Zoological Research LONG
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Reinforcement⁃Learning⁃Based Appointed⁃Time Prescribed Performance Attitude Control for Rigid Spacecraft
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作者 Xiaoning Shi Di Zhou Zhigang Zhou 《Journal of Harbin Institute of Technology(New Series)》 CAS 2023年第1期13-23,共11页
This paper addresses a geometric control algorithm for the attitude tracking problem of the rigid spacecraft modeled on SO(3).Considering the topological and geometric properties of SO(3),we introduced a smooth positi... This paper addresses a geometric control algorithm for the attitude tracking problem of the rigid spacecraft modeled on SO(3).Considering the topological and geometric properties of SO(3),we introduced a smooth positive attitude error function to convert the attitude tracking issue on SO(3)into the stabilization counterpart on its Lie algebra.The error transformation technique was further utilized to ensure the assigned transient and steady state performance of the attitude tracking error with the aid of a well⁃designed assigned⁃time performance function.Then,using the actor⁃critic(AC)neural architecture,an adaptive reinforcement learning approximator was constructed,in which the actor neural network(NN)was utilized to approximate the unknown nonlinearity online.A critic function was introduced to tune the next phase of the actor neural network operation for performance improvement via supervising the system performance.A rigorous stability analysis was presented to show that the assigned system performance can be achieved.Finally,the effectiveness and feasibility of the constructed control strategy was verified by the numerical simulation. 展开更多
关键词 spacecraft attitude tracking appointed⁃time control performance constraints actor⁃critic NNs
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