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The Institut Pasteur of Côte D’Ivoire (Ivory Coast) in the Emergency Management of Air Travellers during the COVID-19 Pandemic: A Unique Experience in Supporting the Response Strategy in Côte D’Ivoire from 2021 to 2022
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作者 Blessa Jean-Claude Anné Tchepé Flore Bernadette Diplo +6 位作者 Kouassi Bernadin Kouame Serge Stéphane Yao Koffi Julien Golly Arouna Sidibe Jacques Kouakou Kouakou Serge Aoussi Mireille Dosso 《Open Journal of Applied Sciences》 CAS 2023年第5期739-745,共7页
Since its outbreak in December 2019 in Wuhan Province (China), the Coronavirus (COVID-19) disease quickly spread around the world in such a way that most response plans were outdated. There was an urgent need to chang... Since its outbreak in December 2019 in Wuhan Province (China), the Coronavirus (COVID-19) disease quickly spread around the world in such a way that most response plans were outdated. There was an urgent need to change and adapt response strategies as the virus globally spread. Entire firms and economies were brought to a standstill in order to reduce the virus’ capacity to spread and to limit some of the short-term impacts in order to save time and find out solutions to come back to a more or less normal way of life. Thus, most of the countries that closed their air, sea and land borders had to reopen them progressively, with travel restrictions submitted to rigid controls. In Côte d’Ivoire, as in all other countries, air travellers leaving the territory were required to provide a certificate for a negative COVID-19 test, valid for 24 to 72 hours depending on the country of destination. However, the national system implemented could not provide a result before 48 hours. The objective of this work was to develop an alternative strategy to the system for air travellers who were in a hurry and those who had a computer bug in obtaining their result. A total of 38,444 air travellers benefited from this strategy implemented by the Institut Pasteur de Côte d’Ivoire during these two years. 展开更多
关键词 cOVID-19 Institut Pasteur de côte D’Ivoire (IPcI) Air Travellers emergENcIES STRATEGY Hurry computer Bug
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Emergency C-Section on Multi-Scar Uterus: Maternal and Fetal Prognosis at the Nianankoro Fomba Hospital in Segou, Mali
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作者 Tidiani Traoré Seydou Traoré +21 位作者 Seydou Z. Dao Abdoul K. Ballo Kassoum Sidibé Brahima Donigolo Babou Traoré Famakan Kané Adama Coulibaly Abdrahamane Diarisso Alima Sidibé Adama Camara Yacouba Dembélé Thierno Boubacar Bagayoko Alpha Sanogo Adama Bah Abdoulaye Kassogue Hamidou Toungara Seydina Alioun Beye Agoustin Thera Youssou Traoré Ibrahima Teguété Niani Mounkoro Amadou Dolo 《Open Journal of Obstetrics and Gynecology》 CAS 2023年第5期997-1005,共9页
Background: Multi-scar uterus is a uterus with two or more scars due to surgery or trauma. Objective: The aim was to compare the maternal and fetal prognosis of emergency C-sections of bi-scar uteruses to those of ute... Background: Multi-scar uterus is a uterus with two or more scars due to surgery or trauma. Objective: The aim was to compare the maternal and fetal prognosis of emergency C-sections of bi-scar uteruses to those of uteruses with at least 3 scars at the Nianankoro Fomba Hospital in Segou. Materials and Methods: It was a descriptive and analytical cross-sectional study with prospective data collection over a 24-month period from March 20, 2018, to March 20, 2020. Results: In 2 years, we collected 103 emergency C-sections for multi-scar uterus out of 1198 C-sections with a frequency of 8.6%. The age group of 20 to 35 years was the most represented with 86.4%. The bi-scar uteruses were the most frequent with 77.7%. In 71.8% of cases, the C-section was performed during the latent phase of labor. The C-section was performed under loco-regional anesthesia in 89.3% of cases. Difficulties in hemostasis and bladder injury were the most frequent intraoperative accidents. Surgical site infection was the main postoperative complication. No maternal deaths were recorded. The perinatal prognosis was marked by 4.3% fresh stillbirths in bi-scar uterus against 3.7% in three or more scar uteruses and including 2 fresh stillbirths and 1 macerated. We did not record any early neonatal deaths after C-section. Conclusion: The frequency of emergency C-sections in patients with a multi-scar uterus remains very high in our hospital. A better awareness of the patients, their spouses and all the actors involved in the management of pregnancies and childbirth, can contribute to curb this trend. 展开更多
关键词 c-Section PROGNOSIS Segou Multi-Scar Uterus emergency
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基于临床特征、REDS评分、炎症标志物的logistic回归模型建立及联合因子对脓毒症预后的预测价值
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作者 张业鹏 毛宇径 +4 位作者 姜毓敏 谢佳丰 刘景荣 徐东 张娈娈 《河南医学研究》 CAS 2024年第11期2029-2033,共5页
目的 分析脓毒症预后不良的影响因素,基于临床特征、急诊可疑脓毒症危险分层(REDS)评分、炎症标志物建立logistic回归模型并验证其对预后的预测效能。方法 选取2021年1月至2023年1月郑州大学第一附属医院收治的脓毒症患者80例为研究对象... 目的 分析脓毒症预后不良的影响因素,基于临床特征、急诊可疑脓毒症危险分层(REDS)评分、炎症标志物建立logistic回归模型并验证其对预后的预测效能。方法 选取2021年1月至2023年1月郑州大学第一附属医院收治的脓毒症患者80例为研究对象,依据入院28 d临床结局将患者分为预后良好组、预后不良组。比较两组临床资料、REDS评分及炎症标志物[C反应蛋白(CRP)、降钙素原(PCT)、肝素结合蛋白(HBP)]水平。多因素logistic回归分析预后不良影响因素,建立logistic回归模型,包括模型1(含有临床特征、REDS评分)、模型2(含有REDS评分、炎症标志物)、联合模型(含有临床特征、REDS评分、炎症标志物)。评价不同logistic回归模型对预后的预测价值。结果 预后不良组血管活性药物使用占比、辅助通气占比高于预后良好组,入院序贯器官衰竭(SOFA)评分、入院急性生理与慢性健康状况评分Ⅱ(APACHEⅡ)、REDS评分及D-二聚体、CRP、PCT、HBP水平高于预后良好组(P<0.05);血管活性药物使用、入院SOFA评分、入院APACHEⅡ评分、REDS评分及D-二聚体、CRP、PCT、HBP水平升高为预后不良的独立危险因素(P<0.05);CRP、PCT、HBP与入院SOFA评分、入院APACHEⅡ评分、REDS评分、D-二聚体呈正相关(P<0.05);联合模型预测预后不良的曲线下面积分别大于模型1、模型2(P<0.05)。结论 基于临床特征、REDS评分及血清CRP、PCT、HBP水平建立logistic回归模型,该模型对脓毒症预后不良具有一定预测价值。 展开更多
关键词 脓毒症 急诊可疑脓毒症危险分层评分 c反应蛋白 降钙素原 肝素结合蛋白
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TT3、TT4、Hcy、Cys C预测脑小血管病认知损害的价值及意义
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作者 彭湘芮 李波 +2 位作者 赵安容 张磊 李智生 《河北医药》 CAS 2023年第24期3726-3730,共5页
目的探讨总三碘甲状腺原氨酸(TT3)、总甲状腺素(TT4)、同型半胱氨酸(Hcy)、胱抑素C(Cys C)预测脑小血管病认知损害的价值及意义。方法选取2019年2月至2021年1月收治的脑小血管病患者129例,根据6个月内是否发生脑小血管病相关认知障碍(CS... 目的探讨总三碘甲状腺原氨酸(TT3)、总甲状腺素(TT4)、同型半胱氨酸(Hcy)、胱抑素C(Cys C)预测脑小血管病认知损害的价值及意义。方法选取2019年2月至2021年1月收治的脑小血管病患者129例,根据6个月内是否发生脑小血管病相关认知障碍(CSVD-VCI)分为障碍组(n=45)和无障碍组(n=84),比较2组基线资料、入院时、3个月后TT3、TT4、Hcy、Cys C、简易智力状态检查量表(MMSE)评分,应用Pearson及偏相关性分析TT3、Hcy、Cys C与MMSE评分关系,采用受试者工作特征曲线(ROC)及ROC下面积(AUC)分析TT3、Hcy、Cys C及联合预测CSVD-VCI价值。结果障碍组高血压、脑白质高信号、静息性脑梗死、脑微出血患者占比高于无障碍组(P<0.05);障碍组入院时、3个月后TT3、MMSE评分低于无障碍组,Hcy、Cys C高于无障碍组(P<0.05);入院时、3个月后TT3与MMSE评分呈正相关,Hcy、Cys C与MMSE评分呈负相关(P<0.05);控制了高血压、脑白质高信号、静息性脑梗死、脑微出血后,入院时、3个月后TT3、Hcy、Cys C均与MMSE评分相关(P<0.05);3个月后各指标及联合的AUC大于入院时各指标及联合对应的AUC。结论TT3、Hcy、Cys C与CSVD患者认知损害的发生有关,联合检测可作为预测认知损害的有效方案,为临床防治CSVD-VCI提供参考。 展开更多
关键词 总三碘甲状腺原氨酸 总甲状腺素tt4 同型半胱氨酸 胱抑素c 脑小血管病 认知损害
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Emergency department targeted screening for hepatitis C does not improve linkage to care
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作者 Inbal Houri Noya Horowitz +4 位作者 Helena Katchman Yael Weksler Ofer Miller Liat Deutsch Oren Shibolet 《World Journal of Gastroenterology》 SCIE CAS 2020年第32期4878-4888,共11页
BACKGROUND Hepatitis C virus(HCV)infection is a leading cause of chronic liver disease worldwide.New treatments for HCV revolutionized management and prompted the world health organization to set the goal of viral eli... BACKGROUND Hepatitis C virus(HCV)infection is a leading cause of chronic liver disease worldwide.New treatments for HCV revolutionized management and prompted the world health organization to set the goal of viral elimination by 2030.These developments strengthen the need for HCV screening in order to identify asymptomatic carriers prior to development of chronic liver disease and its complications.Different screening strategies have been attempted,most targeting high-risk populations.Previous studies focusing on patients arriving at emergency departments showed a higher prevalence of HCV compared to the general population.AIM To identify previously undiagnosed HCV carriers among high risk emergency room attendees and link them to care for anti-viral treatment.METHODS In this single center prospective study,persons visiting the emergency department in an urban hospital were screened by a risk factor-specific questionnaire.The risk factors screened for were exposure to blood products or organ transplantation before 1992;origins from countries with high prevalence of HCV;intravenous drug use;human immunodeficiency virus carriers;men who have sex with men;those born to HCV-infected mothers;prior prison time;and chronic kidney disease.Those with at least one risk factor were tested for HCV by serum for HCV antibodies,a novel oral test from saliva(OraQuick®)or both.RESULTS Five hundred and forty-one participants had at least one risk factor and were tested for HCV.Eighty four percent of all study participants had only one risk factor.Eighty five percent of participants underwent OraQuick®testing,34%were tested for serum anti-HCV antibodies,and 25%had both tests.3.1%of patients(17/541)had a positive result,compared to local population incidence of 1.96%.Of these,82%were people who inject drugs(current or former),and 64%served time in prison.One patient had a negative HCV-RNA,and two patients died from non-HCV related reasons.On review of past medical records,12 patients were found to have been previously diagnosed with HCV but were unaware of their carrier state.At 1-year follow-up none of the remaining 14 patients had completed HCV-RNA testing,visited a hepatology clinic or received anti-viral treatment.CONCLUSION Targeted high-risk screening in the emergency department identified undiagnosed and untreated HCV carriers,but did not improve treatment rates.Other strategies need to be developed to improve linkage to care in high risk populations. 展开更多
关键词 ScREENING emergency departments Israel SALIVA Hepatitis c Liver
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Management of an Unanticipated Difficult Airway during Emergency “C” Section—A Novel Approach
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作者 Ramasamy Govindarajan Christopher Chang +3 位作者 Wesam Khalil Noemi Balogh Elizabeth Cole England Saiganesh Ravikumar 《Surgical Science》 2014年第1期28-31,共4页
Introduction: Knowledge, skill and training in addition to quick thinking, come to the rescue of Anesthesiologists when encountering an unanticipated difficult airway during emergency Caesarean section. Ability to rea... Introduction: Knowledge, skill and training in addition to quick thinking, come to the rescue of Anesthesiologists when encountering an unanticipated difficult airway during emergency Caesarean section. Ability to react with time to spare will ensure maternal and fetal well being while handling this life threatening emergency. Case History: While anesthetizing a 22-year parturient for emergency Caesarean section, the endotracheal tube was inadvertently placed in the esophagus. As the “call for help” was activated, the esophageal tube was delivered thru the endoscopic port of a Patil-Syracuse face mask. After confirming our ability to ventilate the patient without distending the stomach while maintaining the oxygen saturation and end tidal carbon dioxide levels within normal limits, surgery was allowed to proceed under mask anesthesia employing oxygen, nitrous oxide and sevoflurane with rocuronium for muscle relaxation. After a healthy infant was delivered, definitive airway access was obtained with Glidescope? assisted fiberoptic intubation. The esophageal tube was then removed. Further surgery proceeded uneventfully. Discussion: By choosing to deliver the proximal end of the inadvertently placed esophageal tube thru the endoscopic port of a Patil-Syracuse mask and mask ventilating the patient, we have been able to provide that few precious minutes of oxygenation to the distressed fetus before delivery. By isolating and venting the stomach thru the esophageal tube we provided maternal air way protection during the initial phase of the delivery. Definitive airway access was obtained as soon as additional help and equipment were available. Conclusion: Difficult airway algorithm while comprehensive, does not address the question of time management. While dealing with a difficult airway in obstetric anesthesia, time is the single most important factor, which will determine the maternal and fetal well being. We in our case report have attempted to answer that question of “time”. 展开更多
关键词 Unanticipated DIFFIcULT AIRWAY emergency c SEcTION GLIDEScOPE Assisted Fiberoptic INTUBATION DIFFIcULT AIRWAY Algorithm
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Analysis of Evacuation of Tourists Based on the Louvre’s Emergency
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作者 Rui Tang Xiaozhen Luan +2 位作者 Shiwei Xu Fuliang Lu Wei Zhang 《Open Journal of Applied Sciences》 2019年第6期515-534,共20页
Due to France has suffered from many terrorist attacks and the number of visitors to the Louvre has gradually increased in recent years, a good evacuation plan for the Louvre is of vital significance. We use the minim... Due to France has suffered from many terrorist attacks and the number of visitors to the Louvre has gradually increased in recent years, a good evacuation plan for the Louvre is of vital significance. We use the minimization of the total evacuation time of all tourists as the optimization goal to find an optimal path. For conventional emergencies, a static model is built to evacuate visitors. And then we establish a nonlinear programming model. Using Lingo software, we get the distribution information of the visitors in different exhibition halls. For unconventional emergencies, we establish an adaptive dynamic model of tourist evacuation based on genetic algorithm. The sensitivity analysis of the model is considered by adding new paths. By solving the nonlinear programming problem with the double objective function of maximizing evacuation time and balancing the number of people in every path, we get the evacuation time last 1582.74 s. Finally, according to our result, we built mathematical models for the evacuation after an emergency and analyzed how to adapt and implement our models for other large and crowded structures. 展开更多
关键词 NT MODEL Linear Programming Genetic Algorithm cellular AUTOMATA M/G/c/c QUEUING Network MODEL emergency EVAcUATION
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C-V2X网联环境下应急优先的绿灯补偿模型研究
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作者 张长隆 韩发荣 +3 位作者 魏吉敏 戴金钢 杨晓东 瞿仕波 《电信科学》 北大核心 2024年第1期59-70,共12页
针对在路口实施应急车辆优先策略会对非优先相位交通造成影响的问题,在蜂窝车联网(C-V2X)环境下进行了均衡非优先相位通行效益的绿灯补偿模型研究。搭建了相应的算法模型,并对一辆应急车辆的场景进行了模拟。该模型在不影响应急车辆优... 针对在路口实施应急车辆优先策略会对非优先相位交通造成影响的问题,在蜂窝车联网(C-V2X)环境下进行了均衡非优先相位通行效益的绿灯补偿模型研究。搭建了相应的算法模型,并对一辆应急车辆的场景进行了模拟。该模型在不影响应急车辆优先通行的前提下,根据非优先相位实时交通需求计算补偿绿灯时间,从而最小化应急优先对非优先相位的车辆通行影响。仿真结果证明,所提模型在不同的饱和度状态下均可有效地降低应急车辆通过后非优先相位车辆的平均延误时间和平均排队长度。所提模型对于应急车辆通过红绿灯路口的策略进行了优化,提高了通行效率。 展开更多
关键词 应急车辆优先 c-V2X 非优先相位 绿灯补偿 排队长度
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Anesthesia Considerations in Emergency C-Section and Perioperative Neonatal Resuscitation: A Case Report and Review of Literature
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作者 Pratap Nadavaluru Stephen Hannaford +2 位作者 Molly Amin Hee Jung Park Ming Xiong 《Open Journal of Obstetrics and Gynecology》 2018年第9期803-811,共9页
Emergency C-sections are performed for various reasons. This is a case report of emergency C-section performed due to fetal distress. This is a classic case report which emphasizes the importance of managing emergency... Emergency C-sections are performed for various reasons. This is a case report of emergency C-section performed due to fetal distress. This is a classic case report which emphasizes the importance of managing emergency C-sections according to international standards and acknowledges co-operation of obstetrician and anesthesiologist. We reviewed literature about emergency C-sections and discussed sensitive time intervals, types of anesthesia and neonatal resuscitation. 展开更多
关键词 ANESTHESIA for c-Section emergency c-Section PERIOPERATIVE Neonatal RESUScITATION
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新工科背景下“C语言程序设计”课程教学改革探索——以地球物理学专业为例
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作者 吴娟 白敏 《教育教学论坛》 2024年第30期83-86,共4页
“C语言程序设计”是地球物理学专业学生必修的一门重要的专业基础课。由于课程内容较多、实践性较强、部分知识点难度大,在传统教学过程中学生学习的主动性不足,教学效果有待改进。在新工科背景下,通过明确课程目标、强调课程思政的引... “C语言程序设计”是地球物理学专业学生必修的一门重要的专业基础课。由于课程内容较多、实践性较强、部分知识点难度大,在传统教学过程中学生学习的主动性不足,教学效果有待改进。在新工科背景下,通过明确课程目标、强调课程思政的引领作用、增强教学互动、培养学生形成良好的编程习惯、建设全方位的考核评价机制等思路开展教学改革探索,培养具有社会责任感和爱国主义情怀、扎实理论基础和综合实践能力、刻苦钻研精神和创新意识的高级工程技术人才。 展开更多
关键词 c语言程序设计 新工科 课程思政 教学改革 地球物理学专业
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基于遗传算法的TT&C测控资源优化调度(英文) 被引量:11
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作者 吴斌 李元新 黄永宣 《宇航学报》 EI CAS CSCD 北大核心 2006年第6期1132-1136,1167,共6页
TT&C测控资源调度是一个涉及卫星、测控站以及调度准则等多方面因素的复杂优化问题。针对这一优化问题,根据测控调度的一般原则和优化准则,建立了相应的优化模型,并给出了基于遗传算法求解该问题的方法和步骤;最后,通过两个示例分析... TT&C测控资源调度是一个涉及卫星、测控站以及调度准则等多方面因素的复杂优化问题。针对这一优化问题,根据测控调度的一般原则和优化准则,建立了相应的优化模型,并给出了基于遗传算法求解该问题的方法和步骤;最后,通过两个示例分析,演示验证了该方法对于解决一般测控调度问题的有效性。 展开更多
关键词 tt&c 资源调度 遗传算法
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C群奈瑟氏脑膜炎球菌荚膜多糖-TT结合疫苗的制备及其在小鼠体内免疫原性的研究 被引量:5
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作者 吴兵 刘方蕾 +4 位作者 崔萱林 杜琳 杨淼 王志军 冯君平 《微生物学免疫学进展》 2005年第3期12-18,共7页
将C群脑膜炎球菌荚膜多糖以ADH作为间隔剂与TT结合形成GCMP-TT结合疫苗,然后用此结合疫苗免疫NIH小鼠,结果显示使用GCMP免疫小鼠后仅能产生较低水平抗GCMP的IgG抗体,而用GCMP-TT免疫后小鼠血清中产生了较GCMP免疫显著增高抗GCMP的IgG抗... 将C群脑膜炎球菌荚膜多糖以ADH作为间隔剂与TT结合形成GCMP-TT结合疫苗,然后用此结合疫苗免疫NIH小鼠,结果显示使用GCMP免疫小鼠后仅能产生较低水平抗GCMP的IgG抗体,而用GCMP-TT免疫后小鼠血清中产生了较GCMP免疫显著增高抗GCMP的IgG抗体,并且GCMP-TT组第二次和第三次免疫后与初次免疫相比,IgG抗体水平均有显著升高(P<0.01),表明GCMP-TT结合疫苗具有免疫记忆和再次免疫加强应答效应。补体介导的血清抗体体外杀菌试验结果证明,GCMP-TT结合疫苗组免疫小鼠诱导的抗体IgG比GCMP组具有增强的体外杀菌活性。 展开更多
关键词 c群脑膜炎双球菌 荚膜多糖 破伤风类毒素 结合疫苗 免疫原性
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带局部交互的多星TT&C调度合作协同进化 被引量:2
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作者 陈峰 武小悦 《计算机工程》 CAS CSCD 北大核心 2011年第6期250-252,255,共4页
针对现有合作协同进化机制较少利用局部协同信息的问题,通过对多星TT&C资源调度的合作协同进化求解进行改进,在全局协同的基础上加强局部交互,为每个个体设定一个表明其与所有相邻子种群合作效果的进化性能指标——局部交互值,将该... 针对现有合作协同进化机制较少利用局部协同信息的问题,通过对多星TT&C资源调度的合作协同进化求解进行改进,在全局协同的基础上加强局部交互,为每个个体设定一个表明其与所有相邻子种群合作效果的进化性能指标——局部交互值,将该值作为选择操作中衡量个体优劣的尺度之一,以局部交互值与各子适应度之和的差值决定个体变异率,使变异具有自适应性,从而减少由子种群代表个体选择的非全局性造成的优秀个体丢失现象。仿真实验结果表明该方法能较好地提高求解质量。 展开更多
关键词 多星tt&c调度 局部交互 协同进化
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JiTT—Blending Learning理念下的C++课程特色网站开发 被引量:2
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作者 王爱侠 《软件》 2014年第7期44-48,共5页
Ji TT充分体现了Blending Learning的本质特点,把传统学习方式的优势和E-Learning(即网络化学习)的优势结合起来。Ji TT—Blending Learning理念下的C++课程特色网站突破了时间和空间的限制,将多种教学媒体、资源、情境混合,建立了课堂... Ji TT充分体现了Blending Learning的本质特点,把传统学习方式的优势和E-Learning(即网络化学习)的优势结合起来。Ji TT—Blending Learning理念下的C++课程特色网站突破了时间和空间的限制,将多种教学媒体、资源、情境混合,建立了课堂学习和网络学习相结合的模式,给教师和学生提供了一个方便、高效的通过网络教与学C++课程的平台。 展开更多
关键词 Ji tt BLENDING Learning c++课程 B/S
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航天TT&C调度的拉格朗日松弛策略
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作者 康宁 武小悦 陈杨 《计算机工程》 CAS CSCD 北大核心 2011年第19期283-285,共3页
根据航天遥测、跟踪和指挥(TT&C)调度的测控需求,建立航天测控调度问题的0-1整数规划模型,运用(λ,ν)、(μ,ν)和(λ,μ)3种策略对模型中的约束进行松弛,通过次梯度优化算法求得每种松弛问题的上界。利用2个场景验证上界(目标函数... 根据航天遥测、跟踪和指挥(TT&C)调度的测控需求,建立航天测控调度问题的0-1整数规划模型,运用(λ,ν)、(μ,ν)和(λ,μ)3种策略对模型中的约束进行松弛,通过次梯度优化算法求得每种松弛问题的上界。利用2个场景验证上界(目标函数值)的有效性,调度结果表明,3种松弛策略中以次梯度优化算法得到的上界差别最小。 展开更多
关键词 航天遥测 跟踪和指挥 调度 tt&c需求 拉格朗日松弛策略 次梯度优化 上界
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第31届美国ITC会议中的TT&C
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作者 刘嘉兴 《电讯技术》 北大核心 1996年第2期51-58,共8页
本文介绍了第31届美国国际遥测会议的概况。对综合化、数字化、精度自校和BIT、角跟踪、应答机和GPS的技术问题进行了评述。
关键词 测控系统 综合化 数字化 ITc会议 美国 遥测
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测控(TT&C)技术21世纪发展动向预测
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作者 姜昌 《遥测遥控》 2000年第3期1-5,共5页
回顾 2 0世纪后 5 0年 TT& C(遥测、跟踪和遥控 )技术得到大发展的历史背景、TT& C的根本任务和在优势环境下取得的主要成就。根据目前国际形势 ,指出 2 1世纪 TT& C进一步发展所处的主要环境以及
关键词 测控技术 分包遥测遥控 天基深空网
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基于改进蚁群算法的TT&C资源配置方法 被引量:1
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作者 黄萍 拱长青 白元庆 《计算机工程与设计》 CSCD 北大核心 2009年第20期4731-4733,4765,共4页
研究了航天测控网资源配置问题,它是在航天器-地面站有限的时间窗口内对航天器的测控任务进行合理的配置,给每个任务分配一个开始执行时间,在给定的调度时间下,使得任务完成的目标值最大。将引入了杂交算子的蚁群算法来求解该问题,合理... 研究了航天测控网资源配置问题,它是在航天器-地面站有限的时间窗口内对航天器的测控任务进行合理的配置,给每个任务分配一个开始执行时间,在给定的调度时间下,使得任务完成的目标值最大。将引入了杂交算子的蚁群算法来求解该问题,合理地构造了与问题相适应的杂交算子和杂交段。具体的仿真实例表明,在相同的约束条件下该算法总是能最大化地完成任务,并且求得的目标值也有很大的改进。 展开更多
关键词 航天测控网 资源配置 时间窗口 地面站 蚁群算法 杂交算子
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TT viral infection through blood transfusion:retrospective investigation on patients in a prospective study of post-transfusion hepatitis 被引量:8
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作者 Yang SS Wu CH +2 位作者 Chen TH Huang YY Huang CS 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第1期70-73,共4页
AIM To investigate the role of bloodtransfusion in TT viral infection(TTV).METHODS We retrospectively studied serumsamples from 192 transfusion recipients whounderwent cardiovascular surgery and bloodtransfusion betwe... AIM To investigate the role of bloodtransfusion in TT viral infection(TTV).METHODS We retrospectively studied serumsamples from 192 transfusion recipients whounderwent cardiovascular surgery and bloodtransfusion between July 1991 and June 1992.Allpatients had a follow-up every other week for atleast 6 months after transfusion.Eightyrecipients received blood before screeningdonors for hepatitis C antibody(anti-HCV),and112 recipients received screened blood.Recipients with alanine aminotransferase level】2.5 times the upper normal limit were testedfor serological markers for viral hepatitis A,B,C,G,Epstein-Barr virus and cytomegalovirus.TTV infection was defined by the positivity forserum TTV DNA using the polymerase chainreaction method.RESULTS Eleven and three patients,whoreceived anti-HCV unscreened and screened'blood,respectively,had serum ALT levels】90 IU/L.Five patients(HCV and TTV:1;HCV,HGV,and TTV:1;TTV:2;and CMV and TTV:1)were positive for TTV DNA,and four of them hadsero-conversion of TTV DNA.CONCLUSION TTV can be transmitted viablood transfusion.Two recipients infected byTTV alone may be associated with the hepatitis.However,whether TTV was the causal agentremains unsettled,and further studies arenecessary to define the role of TTV infection inchronic hepatitis. 展开更多
关键词 Subject headings blood TRANSFUSION tt VIRAL infection HEPATITIS c ANTIBODY VIRAL
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TT&C系统中测距误差的频率特性分析法 被引量:1
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作者 任然 《电讯技术》 2005年第5期88-91,共4页
以往的文献中,多用群时延来分析TT&C的测距误差,这种方法不够准确和全面。本文采用幅、相频率特性和相位波动特性来分析TT&C信道中的测距误差。详细讨论了由于信道频率特性和相位波动特性变化产生的测距误差,给出了测距侧音相... 以往的文献中,多用群时延来分析TT&C的测距误差,这种方法不够准确和全面。本文采用幅、相频率特性和相位波动特性来分析TT&C信道中的测距误差。详细讨论了由于信道频率特性和相位波动特性变化产生的测距误差,给出了测距侧音相位的数学表达式。运用这些公式可以计算出这些因素对测距漂移误差的影响,提高测距精度。 展开更多
关键词 tt&c 测距误差 频率特性 相位波动特性 分析法
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