Reliability-based life-cycle cost seismic design optimization of coastal bridge piers with nonuniform corrosion using different materials

Reinforcement corrosion is the main cause of performance deterioration of reinforced concrete(RC)structures.Limited research has been performed to investigate the life-cycle cost(LCC)of coastal bridge piers with nonuniform corrosion using different materials.In this study,a reliability-based design optimization(RBDO)procedure is improved for the design of coastal bridge piers using six groups of commonly used materials,i.e.,normal performance concrete(NPC)with black steel(BS)rebar,high strength steel(HSS)rebar,epoxy coated(EC)rebar,and stainless steel(SS)rebar(named NPC-BS,NPC-HSS,NPC-EC,and NPC-SS,respectively),NPC with BS with silane soakage on the pier surface(named NPC-Silane),and high-performance concrete(HPC)with BS rebar(named HPC-BS).First,the RBDO procedure is improved for the design optimization of coastal bridge piers,and a bridge is selected to illustrate the procedure.Then,reliability analysis of the pier designed with each group of materials is carried out to obtain the time-dependent reliability in terms of the ultimate and serviceability performances.Next,the repair time of the pier is predicted based on the time-dependent reliability indices.Finally,the time-dependent LCCs for the pier are obtained for the selection of the optimal design.

Application of Grey System Theory in Design For Cost (DFC)

Design For Cost (DFC) is a branch of Design For X (DFX). In this paper, wedefined DFC as a design method that analyzed and evaluated the product's life cycle cost (LCC), thenmodified the design to reduce the LCC. Nowadays it is a very difficult thing to obtain LCC data inChina or in developing countries. Statistical methods can not be used because available LCC data arefew. In order to solve this problem, we used grey system theory. Then relations of cost factorswere analyzed in LCC using grey relevant methods, and a GM(1,1) model between design parameters andLCC was established. Using this model, we can estimate and control LCC by changing design parametersat the beginning of the design stage.

决策树和Design to Cost在纺织品开发中的应用

采用决策树分析的方法,并应用Design to Cost的概念,对某服装公司产品成本进行了分析,找出了影响产品成本的关键因素,进而降低产品的成本,使产品在市场上更加具有竞争力。

决策树和design to cost在纺织品开发中的应用

本文采用决策树分析的方法，应用Design to cost的概念。对某服装公司产品成本进行了分析．从而找出影响产品成本的关键因素，进而降低产品的成本，使得产品在市场上更加具有竞争力。 决策树是用二叉树形图来表示处理逻辑的一种工具。决策树有一个决策图和可能的结果（包括资源成本和风险）组成，用来创建到达目标的规则。决策树建立并用来辅助决策，是一种特殊的树结构。 Design to cost理念使得人们认识在纺织品的开发中，上游的产品的设计与开发在对产品成本或者最终价格的影响最为重要，而不完全是后期物流、管理方面的花费。 本文巧妙的将这两种分析法结合运用在纺织品开发这样一个复杂的环节中，从而清晰了产品开发的思路，简化复杂的开发过程，最终提高产品的竞争力。

决策树和design to cost在纺织品开发中的应用

本文采用决策树分析的方法，应用Design to cost的概念，对某服装公司产品成本进行了分析，从而找出影响产品成本的关键因素，进而降低产品的成本，使得产品在市场上更加具有竞争力。决策树是用二叉树形图来表示处理逻辑的一种工具。决策树由一个决策图和可能的结果（包括资源成本和风险）组成，用来创建到达目标的规则。决策树建立并用来辅助决策，是一种特殊的树结构。Design to cost理念使得人们认识到在纺织品的开发中，上游的产品的设计与开发对产品成本或者最终价格的影响最为重要，而不完全是后期生产、物流、管理方面的花费。本文巧妙的将这两种分析法结合运用在纺织品开发这样一个复杂的环节中，从而清晰化产品开发的思路，简化复杂的开发过程，最终提高产品的竞争力。

Highway Planning and Design in the Qinghai–Tibet Plateau of China: A Cost–Safety Balance Perspective

Engineering designs for mountainous highways emphasize compliance checking to ensure safety. However, relying solely on compliance checking may lead designers to minimize costs at the expense of high risk indicators, since the overall risk level of the highway design is unknown to the designers. This paper describes a method for the simultaneous consideration of traffic safety risks and the associated cost burden related to the appropriate planning and design of a mountainous highway. The method can be carried out in four steps: First, the highway design is represented by a new parametric framework to extract the key design variables that affect not only the life-cycle cost but also the operational safety. Second, the relationship between the life-cycle cost and the operational safety risk factors is established in the cost-estimation functions. Third, a fault tree analysis (FTA) is introduced to identify the traffic risk factors from the design variables. The safety performance of the design solutions is also assessed by the generalized linear-regression model. Fourth, a theory of acceptable risk analysis is introduced to the traffic safety assessment, and a computing algorithm is proposed to solve for a cost-efficient optimal solution within the range of acceptable risk, in order to help decision-makers. This approach was applied and examined in the Sichuan–Tibet Highway engineering project, which is located in a complex area with a large elevation gradient and a wide range of mountains. The experimental results show that the proposed approach significantly improved both the safety and cost performance of the project in the study area.

决策树和Design to Cost在纺织品开发中的应用

本文采用决策树分析的方法,应用Design to cost的概念,对某服装公司产品成本进行了分析,从而找出影响产品成本的关键因素,进而降低产品的成本,使得产品在市场上更加具有竞争力。决策树是用二叉树形图来表示处理逻辑的一种工具。决策树有一个决策图和可能的结果(包括资源成本和风险)组成,用来创建到达目标的规则。决策树建立并用来辅助决策,是一种特殊的树结构。Design to cost理念使得人们认识到在纺织品的开发中,上游的产品设计与开发不仅影响后期物流、管理方面的花费,且对产品成本或者最终价格有着极为重要的影响。本文将这两种分析法结合运用在纺织品开发环节中,从而清晰了产品开发的思路,简化了复杂的开发过程,最终提高产品的竞争力。

Optimization for performance-based design under seismic demands, including social costs

Performance-based design in earthquake engineering is a structural optimization problem that has, as the objective, the determination of design parameters for the minimization of total costs, while at the same time satisfying minimum reliability levels for the specifi ed performance criteria. Total costs include those for construction and structural damage repairs, those associated with non-structural components and the social costs of economic losses, injuries and fatalities. This paper presents a general framework to approach this problem, using a numerical optimization strategy and incorporating the use of neural networks for the evaluation of dynamic responses and the reliability levels achieved for a given set of design parameters. The strategy is applied to an example of a three-story offi ce building. The results show the importance of considering the social costs, and the optimum failure probabilities when minimum reliability constraints are not taken into account.

Structural Design of Asphalt Pavement for Low Cost Rural Roads

On the basis of the equivalent axle load action frequency, the traffic classifications of rural roads as well as their corresponding types are classified. The asphalt pavement structure, road surface types and thickness of the rural roads are suggested for the various action frequency of the equivalent axle load. Furthermore, the roadbase thickness graphs are provided according to different equivalent axle load action frequency with different roadbed modulus and road surface modulus taken into account.

CO_(2)and Cost-Based Optimum Design of Sustainable Metakaolin-Modified Concrete

Metakaolin is a highly reactive pozzolanic material that is widely utilized for enhancing the performance of concrete.This study offers a framework for the mixture design of sustainable metakaolin-modified concrete with low CO_(2)emissions and low costs.Different design strengths after 28 days are first formulated,with values such as 30,40,50,and 60 MPa.A genetic algorithm is then used to determine the optimal mixtures.Minimized CO_(2)and cost are set as the aims of the genetic algorithm.The strength of the concrete,its workability(slump),and carbonation service life with climate change are set as constraints of the genetic algorithm.Five design cases are considered:1)low-CO_(2)concrete with no carbonation,2)low-CO_(2)concrete with carbonation,3)low-material cost concrete with carbonation,4)low-total cost concrete with carbonation,and 5)low-total cost concrete with climate change.Based on the analysis,the following results are found:1)When the design’s strength is 30 MPa,to satisfy the requirement of carbonation durability,the concrete real strength should exceed 30 MPa.Moreover,after considering climate change,the concrete real strength should be further improved.2)When the design strength is 40,50,or 60 MPa for low-total-cost concrete,climate change has no impact on the optimal design because the concrete has sufficient carbonation resistance.3)Low-material-cost concrete has the same mixture as low-total-cost concrete because compared with the material cost,the CO_(2)emission cost is much lower.Moreover,for low-material-cost or low-total-cost concrete,the metakaolin content is at the lower limit because the price of metakaolin is much higher than that of cement.Summarily,the proposed model covered different aspects of sustainable concrete,such as cost and CO_(2)emissions,clarified various decisive factors of mix design,such as strength and carbon durability,and considered different conditions of climate change,such as no climate change and Representative Concentration Pathways(RCP)8.5.The proposed method is valuable for designing sustainable metakaolin-modified concrete with low CO_(2)emissions and costs.

The Design of Stall-Regulated Wind Turbine Blade for a Maximum Annual Energy Output and Minimum Cost of Energy Based on a Specific Wind Statistic

The design of a stall-regulated wind turbine to achieve a maximum annual energy output is still a formidable task for engineers. The design could be carried out using an average wind speed together with a standard statistical distribution such as a Weibull with k = 2.0. In this study a more elaborated design will be attempted by also considering the statistical bias as a design criterion. The wind data used in this study were collected from three areas of the Lamtakong weather station in Nakhonratchasima Provice, the Khaokoh weather station in Phetchaboon and the Sirindhorn dam weather station in Ubonratchathani, Thailand. The objective is to design a best aerodynamic configurations for the blade (chord, twist and pitch) using the same airfoil as that of NREL Phase VI wind turbine. Such design is carried out at a design wind speed point. Wind turbine blades were optimized for both maximum annual energy production and minimum cost of energy using a method that take into account aerodynamic and structural considerations. The work will be carried out by the program “SuWiTStat” which was developed by the authors and based on BEM Theory (Blade Element Momentum). Another side issue is the credibility of the Weibull statistic in representing the real wind measurement. This study uses a regression analysis to determine this issue.

Improvement of the Life Cycle Costing Method in DesignStage Using KBIMS Library

With the advent of the fourth industrial revolution,the construction industry has undergone a paradigm shift.The smart construction technology market is expected to grow 12%annually in developed countries due to advanced technology investments.It is expected that businesses requiring highly sophisticated technology,for instance companies that need their old facilities upgraded,will become the main focus of the market.As building information modeling(BIM)design is becoming mandatory,such as in the Korea Public Procurement Service,researches regarding building automation,construction,and operation integration management systems based on BIM are conducted.In addition,for construction projects of over 10 billion won,design value engineering(Design VE)implementation,including life cycle cost(LCC)analysis,is mandatory at the design stage to improve quality and reduce the lifetime costs of buildings.In this study,we propose an improvement plan for LCC analysis at the design stage using the KBIMS library,which is an open BIM library developed by the Korean government and research groups.We analyze the existing LCC method,KBIMS library,and attribute information,and model the process that is applied in the LCC analysis system.This is expected to complement the LCC analysis system and improve work productivity.

Design and Development of a Competitive Low-Cost Robot Arm with Four Degrees of Freedom

The main focus of this work was to design, develop and implementation of competitively robot arm with en- hanced control and stumpy cost. The robot arm was designed with four degrees of freedom and talented to accomplish accurately simple tasks, such as light material handling, which will be integrated into a mobile platform that serves as an assistant for industrial workforce. The robot arm is equipped with several servo motors which do links between arms and perform arm movements. The servo motors include encoder so that no controller was implemented. To control the robot we used Labview, which performs inverse kinematic calculations and communicates the proper angles serially to a microcontroller that drives the servo motors with the capability of modifying position, speed and acceleration. Testing and validation of the robot arm was carried out and results shows that it work properly.

Large Cohort Data Based Cost-Effective Disease Prevention Design Strategy: Strong Heart Study

Background and Objective: A multitude of large cohort studies have collected data on incidence and covariates/risk factors of various chronic diseases. However, approaches for utilization of these large data and translation of the valuable results to inform and guide clinical disease prevention practice are not well developed. In this paper, we proposed, based on large cohort study data, a novel conceptual cost-effective disease prevention design strategy for a target group when it is not affordable to include everyone in the target group for intervention. Methods and Results: Data from American Indian participants (n = 3516;2056 women) aged 45 - 74 years in the Strong Heart Study, the diabetes risk prediction model from the study, a utility function, and regression models were used. A conceptual cost-effective disease prevention design strategy based on large cohort data was initiated. The application of the proposed strategy for diabetes prevention was illustrated. Discussion: The strategy may provide reasonable solutions to address cost-effective prevention design issues. These issues include complex associations of a disease with its significant risk factors, cost-effectively selecting individuals at high risk of developing disease to undergo intervention, individual differences in health conditions, choosing intervention risk factors and setting their appropriate, attainable, gradual and adaptive goal levels for different subgroups, and assessing effectiveness of the prevention program. Conclusions: The strategy and methods shown in the illustrative example can also be analogously adopted and applied to other diseases preventions. The proposed strategy provides a way to translate and apply epidemiological study results to clinical disease prevention practice.

中国碳排放权交易机制与实践:基于微观企业股权资本成本的视角

碳排放权交易市场作为企业减排增效的重要机制,引发了资本市场投资者对企业碳排放问题的关注,进而可能影响投资者对企业的风险评估与价值判断。手工整理中国各试点碳市场的控排企业名录发现:碳排放权交易机制显著提升了控排企业的权益资本成本,主要机制为投资者碳风险关注,但该市场机制存在明显的效应边界。进一步发现,当碳市场的初始配额实施部分竞价拍卖和非履约主体交易更为活跃,产品市场竞争程度更高和企业所在城市空气污染更为严重,以及企业非财务绩效表现更好时,碳排放权交易机制对企业权益资本成本的提升作用更为明显。研究结论有助于更为全面的评估我国碳市场建设的经济后果,为该低碳环保政策的持续推广提供理论依据与经验参考。

基于公理设计理论的DFC成本估算软件框架

面向成本的设计是DFx方法的一个分支 ,在满足用户需求的前提下 ,尽可能地降低成本。运用公理设计理论 ,通过分解面向成本的设计对全生命周期成本的需求 ,解除了有关成本要素间的耦合关系 ,建立了面向成本的设计的成本估算软件框架 。

面向成本的设计(DFC)与其他DFX工具的集成与应用方法

DFC(DesignForCost)是DFX方法的一个分支 ,是指在满足用户需求的前提下 ,尽可能地降低成本 ,通过分析和研究产品制造过程及其相关的销售、使用、维修、回收、报废等产品全生命周期中的各个部分的成本组成情况 ,并进行评价后 ,对原设计中影响产品成本的过高费用部分进行修改 ,以达到降低成本的设计方法。选择DFE、DFM、DFA、DFS与DFC进行集成 ,达到综合评价设计方案的目的。采用的方法是以全生命周期成本为核心 ,通过产品生命周期的各个环节 (制造M、装配A、回收R、维修S)的分解和分析 ,给出有关的评价指标体系 ,然后使用设计兼容性分析 (DCA———DesignCompatibilityAnalysis)的方法和模糊理论完成对设计方案的综合评价。

DFC中全生命周期成本数据的收集、处理与使用

在面向成本的设计方法中，全生命周期成本数据可以分为发生在企业内和企业外两部分，对于发生在企业内的成本数据一般可以通过成本会计的数据得到。对于发生在企业外的成本数据（如：维修成本和报废成本数据），需要通过用户调查等方法得到。对于得到的原始成本数据需要去除异常值、通货膨胀等因素的影响后才可以使用。本文通过全生命周期成本与成本核算中成本信息的分析，给出了全生命周期成本数据的收集和使用的途径和原则，为ＤＦＣ中全生命周期成本的计算打下了基础。

面向并行工程的DFC与DTC辨析

对面向成本的设计和按费用设计的思想进行了分析 ,指出 DFC与 DTC的不同之处主要在于 :DFC是一种设计方法 ,DTC在很大程度上属于管理方法 ;DFC主动地运用各种方法降低产品的成本 ,而 DTC是为了获得一个满足给定的目标成本并符合用户要求的设计。两者的相同之处主要体现在从设计入手考虑产品的全生命周期成本。从两者对成本的重视程度、对设计的改进和产生的时间顺序看 ,可以说 DFC是

DFC技术在农业机械设计中的应用

描述了面向成本设计(Design for cost)的概念以及我国农机行业的现状;通过对农机全生命周期的分析,阐述了在我国农机企业中实施面向成本设计的必要性;介绍了在农机设计阶段所需要的成本估算方法,并提出了基于CAD/CAPP模型的农机成本估算框架体系,从而有助于提高我国自主品牌农机的市场竞争力。