直线加速器十年故障分析总结

目的分析和总直线加速器十多年来的故障。方法根据十多年来的故障维修记录，统计和分析直线加速器各阶故障率及故障特点。结果直线加速器使用早期由于机器不稳定故障率比较高，使用中期及其比较稳定，故障率比较低，使用后期由于零部件老化，故障率比较高。     

Using switching detection and variational equations for the shooting method

We study in this paper the resolution by single shooting of an optimal control problem with a bang‐bang control involving a large number of commutations. We focus on the handling of these commutations regarding the precise computation of the shooting function and its Jacobian. We first observe the impact of a switching detection algorithm on the shooting method results. Then, we study the computation of the Jacobian of the shooting function, by comparing classical finite differences to a formulation using the variational equations. We consider as an application a low thrust orbital transfer with payload maximization. This kind of problem presents a discontinuous optimal control, and involves up to 1800 commutations for the lowest thrust. Copyright © 2007 John Wiley & Sons, Ltd.     

步枪立姿射击稳定性的力学特征

射击运动技术是衡量运动员水平的关键，它对运动员姿态控制的稳定性有相当高的要求。本文以步枪立姿运动为例，分析其姿态控制的力学特征，运用运动稳定性原理，求得人体上躯干最佳姿态控制角，并论证了人体躯干长度，前臂长度对稳定性的影响。最后将理论结果与对一些国内外著名运动员实测参数比较分析，证明了理论结论与实际基本相符。     

修复贝尔克血透机同一报警编码不同故障原因的故障

重庆市中医研究院医疗器械维修小组在维修贝尔克(Bellco)公司的formula(tm)型血液透析机压力传感器的不同故障中的心得体会.     

浅谈基层医院护理管理中的安全隐患与对策

目的 分析基层医院影响护理质量的因素,制定相应对策,防止护理差错事故的发生.方法 通过对护理安全隐患的分析,认为主要原因是职能科室和规章制度不健全,护理人员的职业倦怠,流动性大,业务水平低,护理记录不规范等.结果 采取健全科室和规章制度,加强责任心和业务技术的培训,合理调配人力资源,加强护理人员法制观念的教育等措施.提高了护理人员的整体水平,提高了病人的满意度,稳定了护理队伍.结论 通过有效的干预措施,促进了基层医院护理安全,全面提高了护理质量.     

Respiratory Chain Complex-I Defect Mimicking Myasthenia

In a 67-year-old woman with ptosis, double vision, dysphagia, ambiguous Tensilon tests, normal acetylcholine-receptor antibodies, normal thymus, and repeatedly abnormal responses to low-frequency repetitive stimulation, ocular myasthenia was suspected. Pyridostigmin was ineffective, but corticosteroids improved the abnormalities. Despite this therapy, lower-limb weakness developed. Reevaluation disclosed abnormal increase of serum lactate during slight exercise, myogenic electromyography, ragged-red fibers, reduced oxidative enzyme staining and abnormally shaped and structured mitochondria on muscle biopsy, and a respiratory chain complex-I defect on biochemical investigation of the muscle homogenate. Respiratory chain disorder due to complex-I defect with abnormal decremental response to low-frequency repetitive stimulation was diagnosed. It is concluded that respiratory chain disorders due to a complex-I defect may mimic ocular myasthenia clinically, electrophysiologically, and even therapeutically.     

精神分裂症患者凶杀犯罪研究进展

重性精神病以精神分裂症为主,患者受精神症状等多种因素的影响,易发生暴力或凶杀等行为,严重威胁着社会的公共安全,已日益受到社会各界的重视。本文对国内外有关精神分裂症患者凶杀犯罪的研究文献作一综述,为开展精神病患者凶杀研究提供参考。     

Validity and reliability of the TargetScan ISSF Pistol & Rifle application for measuring shooting performance

Several technologies, with varying economic costs, are used to measure the performance of Olympic sport shooters, including electronic targets, laser systems, and mobile phone applications. Nevertheless, the International Shooting Sport Federation (ISSF) does not currently accept any mobile applications as valid measurement systems. The objective of the study was to check the validity and reliability of the TargetScan ISSF Pistol & Rifle application, an automatic mobile application for measuring the performance of shooters via image analysis. A total of 1440 shots were fired by 24 shooters (720 shots each for the air rifle and air pistol events), and the target sheets were analyzed with the application installed on an iPhone X. The official competition results and the measurements from the application were then compared. The results showed an almost perfect reliability for air pistol shots (ICC = .999) and no significant differences between the official average scores and those measured by the application. The reliability was also high for air rifle shots (ICC = .998), but the average scores registered by the application were statistically lower than the official results. We concluded that TargetScan ISSF Pistol & Rifle is a low‐cost, valid, and reliable application for measuring amateur and semi‐professional shooting performance which may be useful to shooters, coaches, clubs, and federations worldwide.     

Parallel indirect solution of optimal control problems

This paper presents an algorithm for the indirect solution of optimal control problems that contain mixed state and control variable inequality constraints. The necessary conditions for optimality lead to an inequality constrained two‐point BVP with index‐1 differential‐algebraic equations (BVP‐DAEs). These BVP‐DAEs are solved using a multiple shooting method where the DAEs are approximated using a single‐step linearly implicit Runge–Kutta (Rosenbrock–Wanner) method. An interior‐point Newton method is used to solve the residual equations associated with the multiple shooting discretization. The elements of the residual equations, and the Jacobian of the residual equations, are constructed in parallel. The search direction for the interior‐point method is computed by solving a sparse bordered almost block diagonal (BABD) linear system. Here, a parallel‐structured orthogonal factorization algorithm is used to solve the BABD system. Examples are presented to illustrate the efficiency of the parallel algorithm. It is shown that an American National Standards Institute C implementation of the parallel algorithm achieves significant speedup with the increase in the number of processors used. Copyright © 2013 John Wiley & Sons, Ltd.