• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2007년도 정기 학술대회 논문집
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• pp.301-306
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• 2007

Design of civil infrastructures is generally based on 2-D drawings and analyses. Design provisions also specify the limit states using member based equations. Most construction projects are done through collaboration of engineers who have different specialized knowledge. Information technologies can dramatically enhance the performance of the collaboration. For the information transfer, we need a mediator between engineers. Object based 3-D models are useful for the communication and for the owners who have to maintain whole the information of infrastructures. In this paper, basic guidelines for the 3-D design according to design phases. Adequate interoperability of 3-D objects from any CAD system is essential for the collaboration. Owners, contractors and design consultants were considered as users of 3-D objects. Cost and performance of each design phases was investigated through the existing data.

• 한국CDE학회논문집
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• 제22권2호
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• pp.129-140
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• 2017

This paper presents a systematic approach for design of timely and proper layouts of a manufacturing system facilitating reconfigurability, referred to as a reconfigurable manufacturing system. A proper methodology for design of a system layout is required for reconfiguration planning - adding or removing machines for supplying the exact capacity needed to fulfill market demands, as well as minimizing the cost of adding new machines. In this paper, theory of constraints is used to make reconfiguration manufacturing systems more cost-effective and efficiency. The proposed approach is validated by using a real industrial case. This paper suggests that the proposed study should be performed concurrently with the design of a new manufacturing system.

• International Journal of Quality Innovation
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• 제7권1호
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• pp.98-111
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• 2006

The paper presents the design of an optical profilometer, a device used for the reconstruction of the micro-geometry of mechanical parts in applications where high precision is needed. The design is based on Robust Design, a major' methodology for quality improvement of engineering systems. Several design solutions, namely different hardware and software setups of the device, are compared in order to select a configuration realising a desired trade-off between performance and cost. The peculiarity of the design strategy is the use of a computer model of the measurement process where the physical part of the process is simulated. This allows for an extensive exploration of the design space, thus opening the way to product innovation.

• 에너지공학
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• 제25권1호
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• pp.43-47
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• 2016

한수원 중앙연구원은 2007년부터 정부과제의 하나로 전기출력이 1500MWe급인 GEN III+ 원전 APR+를 개발해 왔다. APR1400 보다 안전성이 진전된 노형을 개발하기 위해 국내외에서 건설되거나 설계중인 ALWR의 개선된 설계특성을 조사하였다. 국내외의 원전건설 사업에 적합한 APR+ 표준설계를 개발하기 위해 신개념설계특성과 후쿠시마 원전사고 경험을 설계에 반영하였다. APR+의 안전성향상 표준설계 단계(2013.1 ~ 2015.12)에서 한 번의 경제성평가를 수행하였다. 설계 안전성향상 기술개발 단계에의 경제성 평가 결과 APR+ N-th호기는 국내석 탄화력 1000MWe급 대비 39.2% 경쟁력 우위인 것으로 평가되었다. 또한 APR+원전은 해외 원전 선진국 ALWR에 비해 동등 이상 수준의 경쟁력을 확보하는 것으로 평가되었다.

• Korean Chemical Engineering Research
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• 제58권4호
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• pp.550-564
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• 2020

증류탑은 경제적 효율성, 높은 신뢰성 및 자료 확보의 용이성으로 석유화학 공정 설계 시 화학 성분의 분리를 위해 적용되는 주된 기술 중 하나이다. 하지만, 기본적으로 에너지 소비 및 투자비가 높은 설비이기 때문에, 운전비와 투자비에 대한 Trade-Off 분석을 진행하여 가장 경제적인 증류탑 설계 진행이 필요하다. 본 연구에서는 가능한 많은 공정 엔지니어의 활용을 위해 대중적 공정 모사 프로그램인 Aspen Plus를 사용하여 검토를 진행하였다. 증류탑 최적화 진행시의 설계 변수를 정의하여 공정 엔지니어의 주관적인 판단에 의한 설계 품질의 편차를 최소화 하였으며, 불필요한 검토 과정 배제 및 체계적/효율적인 절차를 수립하여 설계에 소요되는 시간 및 인력 소요를 최소화 하였다. 또한, 증류탑 단수 최적화 검토시 투자비의 신뢰성 있는 산출을 위해 APEA (Aspen Process Economic Analyzers) 프로그램을 도입하고, APEA 사용에 대한 효율적인 방법에 대해서도 다방면으로 검토하여 최적화 절차를 수립하였다.

• 대한기계학회논문집A
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• 제39권8호
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• pp.823-830
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• 2015

구조최적설계는 구조물의 성능 개선을 추구하며, 최근에는 구조최적설계는 항공기와 같이 복잡하고 대형인 구조물의 설계에 적용되고 있다. 해석의 정확도를 높이기 위해 유한요소의 수가 증가하는 추세이나 이는 설계 비용의 증가로 이어진다. 이에 부분구조합성법으로써 구분모드합성법이 해석시간 단축을 위해 종종 사용되어 왔다. 본 연구에서는 구조물의 동적특성을 고려하고 해석의 정확도는 유지하면서, 설계에 소요되는 시간과 비용을 줄일 수 있는 설계방법을 제안한다. 제안한 방법은 등가정하중을 이용한 동적응답 최적설계에, 부분구조합성법을 적용하여 설계영역만을 고려한 구조최적설계를 수행하는 것이다. 제안한 방법의 유용성 검증을 위하여 선형 및 비선형 동적응답 최적설계의 예제를 풀이하고, 그 결과에 대해 토의한다.

• Structural Engineering and Mechanics
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• 제86권3호
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• pp.337-348
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• 2023

The optimization of reinforced concrete (RC) cantilever retaining walls is a complex problem and requires the use of advanced techniques like metaheuristic algorithms. For this purpose, an optimization model must first be developed, which involves mathematical complications, multidisciplinary knowledge, and programming skills. This task has proven to be too arduous and has halted the mainstream acceptance of optimization. Therefore, it is necessary to unravel the complications of optimization into an easily applicable form. Currently, the most commonly used method for designing retaining walls is by following the proportioning limits provided by the ACI handbook. However, these limits, derived manually, are not verified by any optimization technique. There is a need to validate or modify these limits, using optimization algorithms to consider them as optimal limits. Therefore, this study aims to propose updated proportioning limits for the economical design of a RC cantilever retaining wall through a comprehensive parametric investigation using the genetic algorithm (GA). Multiple simulations are run to examine various design parameters, and trends are drawn to determine effective ranges. The optimal limits are derived for 5 geometric and 3 reinforcement variables and validated by comparison with their predecessor, ACI's preliminary proportioning limits. The results indicate close proximity between the optimized and code-provided ranges; however, the use of optimal limits can lead to additional cost optimization. Modifications to achieve further optimization are also discussed. Besides the geometric variables, other design parameters not covered by the ACI building code, like reinforcement ratios, bar diameters, and material strengths, and their effects on cost optimization, are also discussed. The findings of this investigation can be used by experienced engineers to refine their designs, without delving into the complexities of optimization.

• 한국경영과학회지
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• 제33권3호
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• pp.77-92
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• 2008

Commonality strategy is a popular design practice in designing a product line as it enables the firm cost saving and simplification in design, manufacturing, and distribution processes. However the issue of commonality has been mostly analyzed from a profit maximizing firm's perspective and, to our knowledge, there is no literature that deals with the issue from a different perspective. in this paper, we consider the issue of commonality strategy from a social welfare maximization perspective, and argue that commonality strategy used in designing of public goods can bring certain benefits not just for a firm but also for consumers, i.e., for society as a whole. While we assume certain cost saving in production process due to economies of scale under commonality strategy, we conceptualize two different effects of commonality strategy, utility effect due to cost saving and weighted-averaging effect, and show how these two effects interplay to determine the design of common attribute and desirability of commonality strategy. We also discuss how the implementation of commonality strategy differs under different objectives of a product line designer : social welfare and firm's profit maximization.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제7권10호
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• pp.2395-2410
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• 2013

Many telecommunication operators around the world have multiple networks. The networks run by each operator are always of different generations, such as 2G and 3G or even 4G systems. Each system has unique characters and specified requirements for optimal operation. It brings about resource allocation problem among these networks for the operator, because the budget of each operator is limited. However, the evaluation of resource allocation among various networks under each operator is missing for long, not to mention resource allocation optimization. The operators are dying for an algorithm to end their blind resource allocation, and the Resource Allocation Optimization Algorithm for Multi-network Operator (RAOAMO) proposed in this paper is what the operators want. RAOAMO evaluates and optimizes resource allocation in the view of overall cost for each operator. It outputs a resource distribution target and corresponding optimization suggestion. Evaluation results show that RAOAMO helps operator save overall cost in various cases.

• Computers and Concrete
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• 제26권4호
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• pp.317-325
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• 2020

A precise estimation of the natural time period of buildings improves design quality, causes a significant reduction of the buildings' weight, and eventually leads to a cost-effective design. In this study, in order to optimise the reinforced concrete frames design, some symmetrical and unsymmetrical buildings composed of solid and hollow members have been simulated using finite element software SAP 2000. In numerical models, different parameters such as overturning moment, story drift, deflection, base reactions, and stiffness of the buildings were investigated and the results have been compared with strength and serviceability limit criteria proposed by Australian Standard (AS 3600 2018). Comparing the results of the numerical modelling with existing standards and performing a cost analysis proved the merits of hollow box sections compared to solid sections. Finally, based on numerical simulation results, two equations for natural time period of moment resisting reinforced concrete buildings have been presented. Both derived equations reflected higher degree of correlation and reliability with different complexities of building when compared with existing standards and relationships provided by other scholars. Therefore, these equations will assist practicing engineers to predict elastic behaivour of structures more precisely.