Safety in international security: a view point from the practice of accident investigation

While security points to a deliberate harming of humans and/or the environment, safety refers to unintended damage. In this view point, I will analyse how the distinction between safety and security matters in the practice of accident investigation and I will argue that the division between the fields is problematic for the assessment of security-related safety risks. Drawing on the case of the our accident investigation into the downing of flight MH17 above Ukraine in 2014, I highlight key dilemmas the Dutch Safety Board dealt with.     

Steady‐state diffusion approximations for discrete‐time queue in hospital inpatient flow management

In this article, we analyze a discrete‐time queue that is motivated from studying hospital inpatient flow management, where the customer count process captures the midnight inpatient census. The stationary distribution of the customer count has no explicit form and is difficult to compute in certain parameter regimes. Using the Stein's method framework, we identify a continuous random variable to approximate the steady‐state customer count. The continuous random variable corresponds to the stationary distribution of a diffusion process with state‐dependent diffusion coefficients. We characterize the error bounds of this approximation under a variety of system load conditions—from lightly loaded to heavily loaded. We also identify the critical role that the service rate plays in the convergence rate of the error bounds. We perform extensive numerical experiments to support the theoretical findings and to demonstrate the approximation quality. In particular, we show that our approximation performs better than those based on constant diffusion coefficients when the number of servers is small, which is relevant to decision making in a single hospital ward.     

Analysis and optimal design of discrete order picking technologies along a line

Order picking accounts for most of the operating expense of a typical distribution center, and thus is often considered the most critical function of a supply chain. In discrete order picking a single worker walks to pick all the items necessary to fulfill a single customer order. Discrete order picking is common not only because of its simplicity and reliability, but also because of its ability to pick orders quickly upon receipt, and thus is commonly used by e‐commerce operations. There are two primary ways to reduce the cost (walking distance required) of the order picking system. First is through the use of technology—conveyor systems and/or the ability to transmit order information to pickers via mobile units. Second is through the design—where best to locate depots (where workers receive pick lists and deposit completed orders) and how best to lay out the product. We build a stochastic model to compare three configurations of different technology requirements: single‐depot, dual‐depot, and no‐depot. For each configuration we explore the optimal design. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008     

基于认知模型的人为差错分类方法

为了保证人为差错分类的全面性和一致性,在详细分析现有人为差错分类方法的基础上,提出了一种新的人为差错分类框架.该框架以"执行差错,忽略"为起点进行细化,得到五种基本的人为差错类别.以此作为人为差错原语,结合认知模型,分析了不同认知阶段可能出现的人为差错模式.实例证明,在这种分类方法指导下来分析人为差错,对提高人为差错分类结果的全面性和一致性有着重要意义.     

在线并列生产装置固有火灾危险度评估

石油化工生产工艺装置复杂 ,工艺控制参数苛刻 ,处理的物料大都具有易燃易爆等特殊的危险性。针对石化生产装置的共同特点 ,通过三套在线并列存在的炼油生产装置 ,从物料特性、工艺装置、工艺控制参数、操作控制等方面综合分析其火灾危险因素 ,并采用美国道化学公司火灾、爆炸危险指数评价法评估装置间的固有火灾危险 ,为消防安全设施的配置以及灭火预案的制定提供依据。     

现代小城镇消防监督管理探析

通过分析目前涌现出的现代化小城镇存在的消防安全问题 ,提出政府重视、建立合理的消防监督管理模式、加强消防宣传等措施 ,改善消防安全环境。     

舰船液压系统用油现状及发展方向

根据舰船液压设备和液压油通常承受高温、高湿、高油雾和辐射等工作特点,分析了舰船液压油的特殊性能要求.此外,通过介绍外军和我军舰船液压系统的主要用油品种、特性和使用方法,结合不断发展的舰船液压技术和日益严格的环境要求,指出品种简化、洁净化、多功能化以及环境友好化是未来我海军舰船液压系统用油的主要发展方向.     

长输管线泵机组状态监测与诊断系统研究

介绍了一个输油泵机组状态监测与故障诊断系统,研制该系统的目的是为了实时掌握输油泵机组的运行状态,为针对性的维护提供依据和手段.设计的系统一方面能对机组的运行状态进行实时监测,产生各种数据报表,另一方面能对机组的常见故障进行诊断分析,及时、准确地对泵机组各种异常状态或故障状态作出诊断,预防或消除故障,同时,也能为泵站运行提供必要指导,减轻管理人员的劳动强度,确保输油泵机组长期、稳定、高效、低耗地运行.     

储油罐计量系统中精度的分析及提高

在储油罐计量过程中,难免会存在测量误差.介绍了储油罐自动计量的3种方法:静压法(HTG)、液位法(LTG)、混合法(HIMS).重点分析了混合法(HIMS)中直接测量参数误差、间接测量参数误差对储油罐计量系统精度的影响,并给出了通过仪表的正确选型与安装、合理地分配计量系统的误差、直接测量参数的软件数字滤波处理等提高计量系统精度的方法措施.对于测量精度要求较高的场合,采用以上方法可以有效地消除测量过程中存在的系统误差,更好地实现在储油品的科学化计量管理.     

油料装备中发动机与油泵的匹配设计探讨

油料装备中发动机与油泵的合理匹配是设计中需解决的一个重要问题。介绍 了油料装备发动机与油泵的匹配原则,分析了油泵和发动机工作时所需的动力,发现发动机 在驱动油泵时具有一定的功率储备,尤其是共用发动机具有较大的功率储备,提出利用发动 机万有特性曲线进行匹配设计。