Deploying a Recall Mitigation Framework for Systems Engineering

This article proposes a novel safety framework for complex systems, called Recall Mitigation Framework, that assists engineering teams in identifying recall risk factors during the systems engineering process. Current frameworks do not address recalls for complex systems. A modified ISO 42010:2011 for identifying multiple stakeholders of complex systems is also proposed, as the current architecture is tailored for systems with only one stakeholder. Existing system engineering tools such as Failure Mode and Effects Analysis are incorporated to identify risks factors. To measure recall propensity of each recall factor, a new formula, called Recall Index (pRI), was also developed and applied in this research. Four activity phases are included within the framework: Stakeholder Identification, Data Acquisition, Statistical Safety Analysis, and Risk Review. Both the Recall Mitigation Framework and pRI are validated through a case study involving the engineering of a new vehicle model in the automotive industry. Use of the framework provided better insights to the engineering team by employing statistical methods to identify three predictive factors that influence vehicle recalls: fuel economy, warranty coverage, and crashworthiness. Managers in other industries can utilize this framework early in the systems engineering lifecycle to identify potential risk factors and prevent a costly recall campaign.     

无缝高压钢瓶热处理规范的探究

本文针对钢质无缝气瓶机械性能的要求,选用35CrMo为瓶体材料,设计了3种热处理实验方案,通过这3种热处理方案的验证比较,寻求能够获得良好综合机械性能的热处理工艺并应用于生产实际,取得了良好效果。     

Unlocking the Power of Systems Engineering for Product and Process Management

ABSTRACT

To improve the efficiency of American industry, it is necessary to create an environment to manage and control the processes that enable complex systems to be created, deployed, operated, supported, and disposed of. Steps toward realizing that environment include process definition, organizational development, assignment of responsibility, and personnel training. Automated support tools are essential for defining and managing the environment and for personnel training. These tools must include abroad range of modeling elements, a three-schema representation system, stored content (data base) and application logic acquisition tools, and a common-sense knowledge base for product definition. This article will provide a background regarding these requirements and will describe efforts to meet the requirements through developing and applying advanced information system technologies.     

A Framework for Reliability Prediction During Product Development Process Incorporating Engineering Judgments

This paper presents a comprehensive framework for reliability prediction during the product development process. Early in the product development process, there is typically little or no quantitative evidence to predict the reliability of the new concept except indirect or qualitative information. The proposed framework addresses the issue of utilizing qualitative information in the reliability analysis. The framework is based on the Bayesian approach. The fuzzy logic theory is used to enhance the capability of the Bayesian approach to deal with qualitative information. This paper proposes to extract the information from various design tools and design review records and incorporate it into the Bayesian framework through a fuzzy inference system. The Weibull distribution is considered as failure/survival time distribution with the assumption of a known value of shape factor. Initial parameters of the Weibull distribution are estimated from warranty data of prior systems to estimate the initial Bayesian parameter ( λ_t). The applicability of the framework is illustrated via an example.     

Membrane Engineering for Green Process Engineering

Green process engineering, which is based on the principles of the process intensification strategy, can provide an important contribution toward achieving industrial sustainable development. Green process engineering refers to innovative equipment and process methods that are expected to bring about substantial improvements in chemical and any other manufacturing and processing aspects. It includes decreasing production costs, equipment size, energy consumption, and waste generation, and improving remote control, information fluxes, and process flexibility. Membrane-based technology assists in the pursuit of these principles, and the potential of membrane operations has been widely recognized in the last few years. This work starts by presenting an overview of the membrane operations that are utilized in water treatment and in the production of energy and raw materials. Next, it describes the potential advantages of innovative membrane-based integrated systems. A case study on an integrated membrane system (IMS) for seawater desalination coupled with raw materials production is presented. The aim of this work is to show how membrane systems can contribute to the realization of the goals of zero liquid discharge (ZLD), total raw materials utilization, and low energy consumption.     

LD30大口径薄壁无缝管成形工艺

介绍了LD30大直径无缝薄壁筒采用热拉伸坯经变薄旋压成形工艺,讨论了其工艺过程,工艺参数和应用范围等.     

A First-Principles Computational Framework for Liquid Mineral Systems

Computer modeling of liquid phase poses tremendous challenge: It requires a relatively large simulation size, long simulation time and accurate interatomic interaction and as such, it produces massive amounts of data. Recent advances in hardware and software have made it possible to accurately simulate the liquid phase. This paper reports the details of methodology used in the context of liquid simulations and subsequent analysis of the output data. For illustration purpose, we consider the results for the liquid phases of two geophysically relevant materials, namely MgO and MgSiO₃. The simulations are performed using the parallel first-principles molecular dynamics (FPMD) technique within the framework of density functional theory. Various physical properties including the equation of state, diffusion, atomic structure and electronic structure of these liquids are obtained as a function of pressure and temperature. The three-dimensional and timedependent data for atomic configuration and electronic density are analyzed using the recently developed spacetime- multiresolution and multiple-dataset-visualization techniques. It is shown that the structural, dynamical and electronic properties of the liquid phases are highly sensitive to compression, with no discernible influence of temperature in most cases.     

A Novel Framework for Building Materials Knowledge Systems

This paper presents a novel mathematical framework for building a comprehensive materials knowledge system (MKS) to extract, store and recall hierarchical structure-property-processing linkages for a broad range of material systems. This new framework relies heavily on the use of computationally efficient FFT (Fast Fourier Transforms)-based algorithms for data-mining local structure-response-structure evolution linkages from large numerical datasets produced by established modelling strategies for microscale phenomena. Another salient feature of this new framework is that it facilitates flow of high fidelity information in both directions between the constituent length scales, and thereby offers a new strategy for concurrent multi-scale modelling of materials phenomena. The viability of this new approach is demonstrated in this paper with two selected case studies: (i) rigid-plastic deformation of a two-phase composite material, and (ii) spinodal decomposition of a binary alloy.     

组织工程用生物材料与系统

当今以工程科学、生命科学原理开发修复、维持或改善组织功能的生物取代物为目标的组织工程正引起先进国家官、产、学各方面的关注,此高新技术不仅能显著提高对疾患的诊治水平,更能形成组织工程产品市场。本文结合１９９６年在加拿大多伦多举行的第５届世界生物材料大会期间举办的组织工程科学展示会为经纬,介绍相关的研究与开发进展。     

Framework for Modeling Dependencies in Collaborative Engineering Processes

This article describes an engineering process representation and modeling tool. The approach is especially suitable for describing large-scale, mature design processes involving numerous tasks, some of which may be performed by automated computer agents. The underlying representation is a graph of information-processing units with explicitly defined input and output feature elements. We show that this representation is more complete than those used in previous process modeling approaches and overcomes some of their limitations when dealing with design processes involving dependencies at multiple levels of detail. The representation is combined with rules for automatically operating upon the graph to preserve consistency when traversing to higher or lower levels of detail.     

CONCORD: A Control Framework for Distributed Real-Time Systems

Novel network technology combined with advances in hardware development have permitted the enabling of distributed real-time systems and have shortened the time-to-market period. Distributed frameworks, also known as middleware, are often used to integrate enterprise systems, shorten the development time, and reduce complexity. However, to deploy standard middleware in robotics and control applications, we have to deal with the challenge of producing predictable outputs. Most real-time applications in these areas are developed in ad hoc manner, and as such, it is hard to migrate them to new platforms. To overcome this issue while minimizing development effort and increasing reusability for distributed real-time systems, we propose a control framework for distributed real-time systems based on standard middleware specifications. The control framework is composed of asynchronously running task modules, which can be located on either the local or the remote machines. The task modules are connected by an event channel, which uses the publish/subscribe communication method. We also have developed an adaptive event channel in order to meet real-time system requirements and to produce predictable outputs. Detailed development of the control framework along with the adaptive event channel are assessed through a set of experimental results.     

A Mathematical Framework for the Key Characteristic Process

To maximize product quality, a product design team selects concepts and dimensions to minimize a product’s sensitivity to variation. However, even for the most robust products, it is rarely possible to transition a product into production without encountering any variation-related problems. In a complex product, it is not economically or logistically feasible to control and/or monitor the thousands of tolerances specified in a product’s drawing set. To address this problem, many organizations are using Key Characteristic (KCs) methods to identify where excess variation will most significantly affect product quality, and what product features and tolerances require special attention from manufacturing. As simple as this principle seems, most companies struggle to effectively implement KC methods because no quantitative methods to prioritize KCs exist. This paper develops a mathematical definition of a KC based on a variation propagation model. In addition, it develops a quantitative effectiveness measure used to prioritize where verification, variation reduction, and on-going monitoring should be applied. The effectiveness measure incorporates the cost of control, the benefit of control, and the expected change in process capability. The methods are illustrated using an automotive door assembly.     

无缝气瓶热旋压收口成形工艺数值模拟研究

本文采用有限元分析软件ABAQUS对无缝气瓶热旋压收口成形工艺进行模拟研究,分析了不同工艺参数对气瓶热旋压成形的影响。模拟结果表明,无缝气瓶热旋压收口成形过程中,随着旋压温度的升高和进给比的增加,起旋点处最小壁厚减薄,瓶肩最大壁厚处壁厚增加;随着旋压温度的升高,最大等效应力不断减小,最大等效应变不断增加;随着进给比增加最大等效应力应变都略有增加;旋压力随着温度的升高和进给比的减小而降低。     

工程图技术要求自动生成工具的设计与实现

针对我国企业用户的应用需求,实现了工程图技术要求自动生成工具。本文着重阐述了设计过程中技术要求数据库的设计、工程图技术要求自动生成工具与数据库、AutoCAD系统的通讯以及实现自动标注等关键技术,并给出了具体开发实例,从而简化了技术要求的标注操作和技术要求数据管理。     

创建知识系统工程学科

介绍了如何在钱学森的系统科学与思维科学思想的启发和指引下，创建知识系统工程学科，知识系统工程的任务与内涵，知识系统的组成要素和功能；提出了知识系统的组织、人员、技术、经营和文化的体系结构；分析了知识系统的运作过程；特别对创新过程中知识的集成、转化与新知识的生成提出了一些新的观点。     

超声C扫电子性能计量方法分析

超声检测技术是特种工艺检测中不可缺少的重要手段之一,本文分析了成飞公司现阶段所涉及的超声C扫描系统有关设备电子性能校准的方法和特种工艺要求,对校准项目、测量原理等进行了剖析。基于工信部民机专项科研标准化的要求,为编写国内民机超声C扫描校准行业规范做准备,并对未来超声系统校准趋势进行了探讨。     

工程项目物流管理框架模型

提出工程项目物流的概念,构建了物流管理框架模.其关键环节包括识别业主、设计行商、承包商的三重角色及供应商的新角色,制定物料需求计划、作业层物料跟踪系统,确定库存,建立供应商的主动交付以及专门的物流管理小组,并分别研究了它们的运作过程和责任.工程项目物流管理的完善对于提高工程项目的科学管理水平有重要意义.     

基于全生命周期的企业流程再造(BPR)模型框架

本文依据流程再造理论与实践相结合的原则,建立了一个比较可靠的流程再造模型,提出了企业流程再造应该是包括功能、组织和信息系统的全周期流程再造的再造新观点,并给出了流程再造的策略、建模方法及在思想、流程及组织三方面的再造规则。