65 research outputs found
Study on Cooperation Mode of E-ticket Online Distribution Channels
传统旅游业与信息和通信技术的结合催生了在线旅游业。近年来在线旅游业的蓬勃发展成就了无数从业企业,客户数量增长迅速,也得到了许多投资者的青睐。电子客票在线分销作为在线旅行预订最重要的部分,其行业竞争日趋激烈,不断出现新的商业模式,企业之间的关系也更加错综复杂。因此有必要研究电子客票在线分销渠道的合作模式,为创造更加稳定的合作环境提供借鉴。 本文通过分析电子客票在线市场的发展现状及其产业链构成,构建了电子客票在线分销渠道的服务供应链模型,讨论了分别以在线代理、C2C平台和旅游搜索为整合服务提供商所形成的三种模式。同时,详细阐述了电子客票的定价机制和市场供求状况,总结了借鉴供应链契约分析电子客票在...The combination of traditional travel industry and ICT (Information and Communication Technology) generates online travel industry. Recently, the booming development of the industry has been making many famous enterprises, appealing to more and more clients and investors. As the most important part of online travel booking, e-ticket online distribution market is undergoing an intense competition, ...学位:管理学硕士院系专业:管理学院管理科学系_技术经济及管理学号:1772007115073
Correlation between use of social software and high risk behaviors of HIV infection among MSM in Beijing
目的了解北京市男男性行为者(MSM)社交软件的使用与人类免疫缺陷病毒(HIV)感染及其影响因素的相关性,为今后干预工作提供依据。方法 2016年3—5月,由社区小组招募MSM进行问卷调查,同时进行HIV抗体检测。结果共招募215名MSM,回收有效问卷214份。214人的平均年龄为30.8岁;学历在大专及以上者占73.4%;同性恋者占72.4%;84.6%的人主要通过社交软件寻找性伴。214人中确证HIV感染5人,阳性率为2.3%。分析显示,是否使用社交软件、是否使用同性社交软件和是否使用普通人群社交软件均与HIV感染不相关。多因素分析结果显示,受教育程度高、性取向为同性恋的人更多地使用同性社交软件。63.1%被调查者自述曾经在社交软件上了解到艾滋病防治相关知识,但自述了解程度与是否通过社交软件获得相关信息不相关。结论 MSM社交软件的使用与HIV感染情况无关,也没有增加其对艾滋病知识的了解。但可以考虑改进同性社交软件功能,增加艾滋病防治知识内容,对MSM尤其是高学历、自我定位为同性恋的MSM进行艾滋病防治宣传。[Objective] To understand the correlation between the use of social software and human immunodeficiency virus(HIV)infection and its influencing factors among men who have sex with men(MSM)in Beijing,provide the basis for future intervention work.[Methods]From May to March in 2016,MSM was recruited by community groups to carry out a questionnaire survey and HIV antibody of them was detected.[Results]A total of 215 MSM were recruited and 214 valid questionnaires were recovered. The average age of the 214 MSM was 30.8 years old,73.4% had the education level in college and above,the homosexuals accounted for 72.4%,and84.6% of the respondents mainly found sexual partners through the social software. There were 5 cases of confirmed HIV infection among 214 MSM with the positive rate of 2.3%. The analysis revealed that whether the respondents use the social software,the homosexual social software and the general social software were not related to HIV infection. The results of multivariate analysis showed that people with higher educational level and homosexual orientation were more likely to use the homosexual social software. 63.1% of respondents reported that they had been obtained the knowledge of AIDS prevention and control from social software,but the understanding level was not related to whether the relevant information was obtained through social software or not.[Conclusion]The use of social software has no correlation with HIV infection among MSM,and does not increase their knowledge level of AIDS prevention and control. However,it is necessary to improve the function of the homosexual social software and increase the content of AIDS prevention and control knowledge to carry out the AIDS education among MSM,especially those with higher educational level and homosexual orientation
BP神经网络和ARIMA模型对污水处理厂出水总氮浓度的模拟预测
污水处理厂出水总氮(TN)浓度是评价水处理效果的关键指标之一,利用BP神经网络建立模型对污水处理厂脱氮工艺进行模拟,引入自回归移动平均模型(ARIMA)对污水处理厂未来短期出水TN浓度进行预测..
BP神经网络和ARIMA模型对污水处理厂出水总氮浓度的模拟预测
污水处理厂出水总氮(TN)浓度是评价水处理效果的关键指标之一。建立BP神经网络模型对污水处理厂脱氮工艺进行模拟,引入自回归整合移动平均模型(ARIMA模型)对污水处理厂未来短期出水TN浓度进行预测。结果表明:BP神经网络模型在训练集和测试集模拟结果的平均相对误差分别为15. 9%和16. 5%,模型预测结果的平稳性较差; ARIMA模型对未来7 d出水TN浓度的时序预测平均误差为4. 41%,预测精度较高; 2个模型相结合有助于实现污水处理厂快捷和高效的在线检测。福建省自然科学基金项目(2018J01016);;\n厦门大学大学生创新创业训练计划项目(2018X0256
Y型聚乙二醇干扰素琢-2b注射液治疗HCV基因2/3型慢性丙型肝炎患者疗效和安全性的多中心随机对照试验研究
目的以标准剂量的聚乙二醇干扰素(Peg IFN)α-2a联合利巴韦林作为阳性对照,评价新型试验药物Y型Peg IFNα-2b注射液联合利巴韦林治疗2型/3型慢性丙型肝炎(CHC)患者的疗效和安全性。方法采用多中心、随机开放、阳性药对照的Ⅲ期临床试验,筛选符合要求的2型/3型CHC患者,按照2:1的比例随机分配到Y型Peg IFNα-2b组和Peg IFNα-2a组,同时口服利巴韦林,疗程24 w,停药随访24 w。采用Abbott Real Time HCV Genotype II检测HCV基因型,采用Cobas Taq Man实时定量PCR法检测血清HCV RNA水平。详细记录不良事件。主要疗效指标为持续病毒学应答(SVR),并进行非劣效检验。结果本试验实际入组2型/3型CHC患者255例,实际治疗241例。全分析集(FAS)数据显示,158例试验组和83例对照组患者SVR分别为85.4%(95%CI 79.94%~90.94%)和79.5%(95%CI 70.84%~88.20%,P=0.2402);对符合方案分析集(PPS)人群分析显示,试验组和对照组患者SVR分别为87.9%(95%CI 82.45%~93.27%)和85.9%(95%CI 77.82%~94.01%,P=0.7060),率差的95%可置信区间均符合非劣效标准;对PPS人群分析显示,85.8%受试者获得了早期病毒学应答(RVR),RVR的阳性预测值为90.1%;试验组和对照组不良事件发生率相似,分别为95.6%和95.2%,严重不良事件发生率分别为3.8%和3.6%。结论应用Peg IFNα联合利巴韦林治疗2型/3型CHC患者,新型试验药物Y型Peg IFNα-2b具有与对照药物Peg IFNα-2a相似的疗效和安全性。国家科技部“十二五”重大专项(编号:2012ZX10002-003);“重大新药创制”十二五科技重大专项(编号:2012ZX09303019)
Review of flow and heat transfer of supercritical carbon dioxide
This paper gives a review of the heat transfer and pressure drop characteristics of supercritical carbon dioxide in-tube flow.Some published correlations for heat transfer coefficient and pressure drop during in-tube cooling are collected.The accuracy of the correlations are discussed through comparing the calculation results with the experimental data.The shortages of current researches are pointed out
Review on Heat Transfer of Subcritical Carbon Dioxide
This paper gives a review of the heat transfer characteristics of subcritical carbon dioxide in-tube flow. Some published correlations for heat transfer coefficient during in-tube flow are collected. The accuracy of the correlations is discussed through comparing the calculation results with the experimental data. The applicable correlations in different conditions are recommended
基于遗传算法的3-PCR减振平台等效刚度设计
基于3-PCR并联机构,通过在主动副处添加弹簧阻尼装置构建并联减振平台,推导了3-PCR机构的运动学方程并对其工作空间进行了分析。选择该减振平台上下平台半径、杆长以及杆与下平台夹角作为设计变量,研究了上述4参数对最大球形工作空间的影响规律。引入等效刚度的概念,采用遗传算法对上述参数进行了优化设计,以期得到满足特定等效刚度要求的减振平台,该平台在微幅振动下其等效刚度值接近恒定。工程应用中减振平台的等效刚度均可使用该设计方法予以实现,为基于并联机构的减振平台设计提供了一种新方法
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