On efficiency of the ratio estimator

Summary The exact mean square error for the ratio estimator of a finite population total based on simple random sampling without replacement is shown to have an expected value less than that of the variance of the ratio estimator based on Midzuno’s scheme, under a usual super-population model.     

知识产权侵权归责原则探析——谈无过错责任原则的不适用

知识产权侵权损害赔偿采用何种归责原则,事关知识产权权利人的权益及普遍公众的公共利益.无过错责任原则在知识产权侵权损害赔偿领域的适用打破了知识产权权利人和公共利益的平衡,影响了知识产权制度平衡机制的正常运转,歪曲了知识产权激励机制的本意,束缚了一般民事主体创造知识产品的热情.无过错责任原则在知识产权领域的适用有其天然的弊端和不足,而TRIPS协议第45条也并未将该原则作为一般原则来对待,即便按照民法学方法分析,知识产权侵权损害赔偿也不应适用无过错责任原则.     

抽油泵凡尔罩可靠性分析及对策

石油开采过程中，抽油泵凡尔罩故障性断脱的频繁发生．不仅加大了采油作业工作量．增加了采油成本．同时也严重影响了原油产量。河南双河油田每年都有60-80口油井的抽油泵凡尔罩发生断脱?指出凡尔罩断脱主要表现为磨损、变形、腐蚀、脱扣等4种形式．分析归纳了造成凡尔罩断脱失效的主要影响因素有6个方面：凡尔罩材质选用不合适，油井深，凡尔罩结构不理想，柱塞上下往复运动所产生的交变应力对凡尔罩造成疲劳损坏，老油井含砂量高使凡尔罩内壁形成研磨划伤，加工工艺流程不合理。针对上述原因．提出了提高凡尔罩质量可靠性的4项主要技术措施：在修复泵时更换凡尔罩材质，将凡尔罩原热处理工序流程进行调整，运用渗氮技术对凡尔罩进行表面化学热处理，对凡尔罩的结构进行优化改进。采用以上措施所产生的积极效果在现场得到了验证：双河油田2003年以来．73口油井采用了改进后的凡尔罩，在保持产液量不变的状况下，投用至今未发生一起断脱事故．效果良好     

数字化分析技术在提高阀门检验质量中的应用

针对传统阀门质量检验统计分析以人工统计为主、耗时长、效率低、时效性差、结果不准确等问题,通过开发智能质量检验统计分析系统,自动采集压力试验数据,自动生成检验记录、检验报告以及各类报表,还可以根据制造厂商、阀门类型、缺陷种类等自动生成柱状图、饼状图等质量分析图表,降低了人工录入数据的差错率,检索统计准确迅速,提高了检验效率和检验质量,为产品质量管理提供了快捷、高效的决策数据。     

Comparing post-operative resource consumption following transcatheter aortic valve implantation (TAVI) and conventional aortic valve replacement in the UK

Objective:

To define the in-hospital and 6-month post-discharge resource use, following Transcatheter Aortic Valve Implantation (TAVI) and conventional Aortic Valve Replacement (AVR) surgery within a single UK hospital.

Methods:

A local service evaluation of patients undergoing TAVI or AVR between January 2011 and May 2012 captured data until 6-months post-procedure, collected from hospital records and via a General Practitioner questionnaire. The main end-points were mortality, time in ITU/HDU, hospital length of stay (LoS), discharge destination, re-admission, and post-discharge primary/secondary care resource use. Sub-group analyses were performed for AVR patients aged ≥80 (AVR?≥?80) and with EuroSCORE of ≥10 (AVR ES?≥?10) to allow more direct comparison with ‘TAVI type’ patients.

Results:

Results are given as means (standard deviation) for TAVI (n?=?51), AVR (n?=?188), AVR?≥?80 (n?=?48), and AVR ES?≥?10 (n?=?47), respectively, unless otherwise stated. Age in years was 83.0 (8.1), 71.2 (13.1), 84.1 (2.7), 79.4 (7.1); EuroSCORE was 24.7 (11.9), 8.1 (6.4), 12.0 (6.0), and 16.5 (6.6); post-operative LoS (days) was 11.5 (11.2), 10.9 (10.8), 14.3 (16.7), and 15.2 (17.7). For discharged patients, 0%, 7%, 13%, and 9% had unplanned cardiac-related re-admissions within 30-days of discharge. Time to first readmission was 74.6 (34.0), 35.0 (34.2), 20.8 (9.7), and 22.6 (14.3) days.

Limitations:

This was a single-center retrospective evaluation, not prospectively powered to confirm differences in outcomes.

Conclusions:

Despite TAVI being performed in an older, higher risk population, LoS was similar to AVR. Most strikingly there were no cardiac-related re-admissions within 30-days for TAVI and time to first re-admission was significantly longer. This evaluation suggests that TAVI is clinically appropriate and provides economic advantages in both the hospital and post-discharge setting in this high risk group. Many patients undergoing TAVI are considered unfit for surgery and, hence, TAVI offers a treatment that delivers similar results to traditional AVR without the high risk associated with surgery.     

北宋孤幼、户绝财产检校制度辨析

财产检校制度是宋代朝廷对社会孤幼家庭的财产或者有争议财产进行代管、到期归还的一种强制性财产管理制度,主要有孤幼财产检校和户绝财产检校.其中前者直接承袭唐五代,后者于太平兴国二年正式确立.北宋前期开封府的财产检校一般由内侍省和三司临时受朝廷旨意施行,开封府检校库约于庆历四年出现,用以管理并存放检校财产,地方州军存放在军资库(元符二年后存放在常平库).这是中国古代社会产权制度一大发展.     

均值-极差控制图在阀门质量控制中的应用

产品的质量控制是企业获取市场的重要保证。针对阀门关键质量指标,结合企业生产现场采集阀门直径数据,借助minitab软件对所测得的数据进行统计处理,绘制出阀门直径的均值-极差(-R)图,据此断判出生产过程的质量控制状态,为阀门生产过程的质量控制提供了保障。     

减压阀(调节阀)在兰成渝管道中的应用

减压阀是长输管道的重要设备之一,能够通过调节长输管道的压力大小进而实现对管道安全的保护。本文根据减压阀在兰成渝输油管道应用八年以来的实际经验,从减压阀的结构及原理、维护保养、维修安装、常见操作及故障分析等几个方面介绍减压阀以及其在应用过程中的改进。     

供热系统中平衡阀的性能与用途

本文主要阐述了供热系统中手动平衡阀、自力式压差控制阀、自力式流量控制阀、自力式流量控制阀的选择、自力式流量控制阀在暖通工程中的应用等问题。     

论无权处分的法律效力

无权处分的法律效力一直就有争论,相关论文也非常多。在主张物权行为与债权行为区分对待和坚持物权行为有因性的前提下,对无权处分的法律效力加以区分控制。