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.

Study on Influencing Factors and Control Points of Design Estimate of Landscaping Engineering

In recent years,China’s landscaping projects have developed vigorously,and the growth rate of urban garden green space areas has been maintained at about 5%.Overall,with the development of the national economy and the support of macro policies,people’s demand for close to nature and beautify the environment is gradually increasing,which has brought new growth momentum for the development of the landscaping industry.Simultaneously,from the perspective of future economic development and urban development,the landscaping industry still has a lot of room for development.However,with the rapid development of landscape engineering,the problem of cost control of landscape engineering is becoming more prominent,the phenomenon of budget overestimation is common,and there are many factors affecting the cost of landscape engineering,which brings difficulties and challenges to the analysis of its influencing factors and cost management.How to scientifically analyze the influencing factors and control the cost has become an important link in the landscaping project.To solve the above problems,this paper takes the design stage of landscaping engineering as the background,takes the design estimate of landscaping engineering as the research object,through literature research and data collection,fully excavates the main influencing factors of the design estimate stage of landscaping engineering,analyzes the key points of cost control,and provides reference ideas and directions for the later cost management and control.

Low-cost Plant Landscape Design of Small-scale Residential Area——A Case Study of Huayu Residential Area on Baoping Road in Baoji City of Shaanxi Province

Modern landscape emphasizes the resource conservation and sustainable development.Simple and fine residential green areas should be the development trend.Taking the landscape design of Huayu residential area on Baoping Road in Baoji City of Shaanxi Province as an example,the way how to create a fine view and a good ecological environment for the people living in the bustling city with less investment and simple maintenance was analyzed.

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.

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。

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。

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。

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。

卫星低成本策略与实践研究

随着航天产业的发展,低成本已经成为卫星研制转型的重要特性.“如何迎接低成本挑战,达到既符合市场发展需求,又风险可控的卫星研制策略”是卫星研制的重要议题.首先从成本内涵的角度出发,论述了成本度量与低成本的内涵;然后从目标体系、组织管理机制及经营策略等方面,对卫星低成本研制策略进行了探索;最后从技术方案、产品实现、发射运行、应用服务及条件保障等方面,对卫星低成本设计技术进行了全方位研究.本研究工作旨在为卫星规模化发展提供理论与实践指导.

多冗余模式下综合能源系统两阶段优化配置

在综合能源系统向复杂化、高耦合度发展的过程中,设备单元运行可靠性降低与高昂的设备运维成本问题难以忽视。针对上述问题,从内部配置结构优化的角度,将系统工程中主、被动冗余思路引入综合能源系统,完成子系统单元的冗余设计。提出了一种针对冗余设备逻辑最优工况匹配的两阶段流程,以实现全系统整年运行优化。从经济、能源和环境3方面建立评价指标,基于蜜獾算法对两建筑、四系统进行案例研究。结果表明:所提3种冗余系统均实现了可靠性与各性能指标的明显提升;主动冗余系统年度总运行成本最低,热备用系统可靠性表现最好,冷备用系统综合性能最佳。

低成本小批量微纳卫星控制系统的研制实践

针对微纳卫星的研制特点,结合控制系统研制过程中的具体实践,从单机产品设计、系统方案设计、测试和环境试验,以及软件开发方面,给出了微纳卫星降低成本、提高可靠性与研制效率的措施和建议.通过采用控制系统内部的冗余备份设计,以及系统级可靠性措施,简化了系统配置,并提高了系统可靠性.通过进行系统级的热循环试验可降低研制成本,并达到可靠性试验筛选的目的.通过开展平台化和通用化设计,完善和改进软件开发流程,提高了研制效率.所述方法和措施在卫星研制中取得了较好的效果.