• Korean Journal of Computational Design and Engineering
• /
• v.5 no.3
• /
• pp.263-275
• /
• 2000

Multidisciplinary design optimization(MDO) can yield optimal design considering all the disciplinary requirements concurrently. A method to implement the collaborative optimization(CO) approach, one of the MDO methodologies, is developed using a pre-compiler “EzpreCompiler”, a design optimization library “EzOptimizer”, and a common object request broker architecture(CORBA) in distributed computing environment. The CO approach is applied to a mathematical example to show its applicability and equivalence to standard optimization(SO) formulation. In a realistic engineering problem such as optimal design of a two-member hub frame, optimal design of a speed reducer and initial design of a bulk carrier, the CO yields better results than the SO. Furthermore, the CO allows the distributed processing using the CORBA, which leads to reduction of overall computation time.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2001.10a
• /
• pp.201-210
• /
• 2001

In this study, large-scale distributed design approach for a life cycle cost (LCC) optimization of steel box girder bridges was implemented. A collaborative optimization approach is one of the multidisciplinary design optimization approaches and it has been proven to be best suited for distributed design environment. The problem of optimum LCC design of steel box girder bridges is formulated as that of minimization of the expected total LCC that consists of initial cost maintenance cost expected retrofit costs for strength, deflection and crack. To discuss the possibility of the application for the collaborative optimization of steel box girder bridges, the results of this algorithm are compared with those of single level algorithm. From the numerical investigations, the collaborative optimization approach proposed in this study may be expected to be new concepts and design methodologies associated with the LCC approach.

• Journal of Climate Change Research
• /
• v.2 no.2
• /
• pp.115-131
• /
• 2011

Out of all the possible actions that can be taken to respond to greenhouse gas reduction, including development of greenhouse gas reduction technology, infrastructure, actions to improve energy saving and efficiency, and offset with carbon emission reductions (CERs), this study shall focus on the investment on CERs. This study will take a look at risks involved with investing in CERs such as UN registration refusal risk and CERs price fluctuation, and will design risk management model which shall be verified. The goal of this paper is to provide optimized CERs investment strategies for different types of investors, such as general trading companies seeking for investment opportunities and financial companies with plans for green products development and investment by preparation for carbon market. It is expected that the global competitiveness of domestic financial companies shall be improved by taking actions on carbon market instead of previous passive response to climate change and that Korea, the number two Carbon Emissions supplier and number one derivatives market in terms of volume, shall be able to lead the worldwide carbon market.

• Journal of the Korea Concrete Institute
• /
• v.28 no.6
• /
• pp.703-711
• /
• 2016

The present study is mainly aimed at securing adequate pores which are applicable to the aquatic environment and satisfying the required strength of porous concrete as a structure by substituting pumice for crushed stone which is usually used for the fabrication of porous concrete. Accordingly, in order to deduce the optimum mixing conditions applicable to the aquatic environment, we sought to evaluate the porosity, coefficient of permeability and compressive strength of porous concrete based on the target porosity and the mixing factors for pumice. By examining the porosity and coefficient of permeability of porous concrete and the physical properties of its compressive strength based on the target porosity and the mixing factors for pumice, it is judged that the optimum mixtures for porous concrete applicable to the aquatic environment which satisfy both the necessity of securing adequate pores and the required strength for porous concrete as a structure are PC I I-10-0, PC I I-10-5 and PC I I-10-10.

• Journal of Digital Convergence
• /
• v.13 no.2
• /
• pp.1-11
• /
• 2015

The growing company that provides high quality service to every customer by introducing a cloud-system organization. However, the information needs of diverse and different, so every cloud system, and acts as a barrier to entry for cloud services provide appropriate. Cloud services are becoming complicated and diversified depending on concerns about cloud security continues, the growing need of professionalism held by the cloud service(Cloud Service Brokerage) CSB companies. Thus, to analyze the various services, find my support legislation, security and compatibility issues, the services of the best new business through service offerings tailored to the environment, and will implement the necessary management services which brokerage (CSB) is. This study presents a brokerage(CSB) development model, and suggested policy measures that apply to the co-op that I am having difficulties in cloud services business models.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2010.07a
• /
• pp.293-296
• /
• 2010

현재 지능형 서비스로봇이 활성화되고 있으며 지능형 로봇 분야에서 청소로봇은 개인생활의 본질적인 운동성을 보조하며 인간과 공생의 형태를 지원하는 로봇으로 성장하고 있다. 청소로봇은 가정에서 다양한 서비스를 제공하기 위하여 가정환경과 적절한 상호작용은 필수적이다. 따라서 로봇이 외부의 서버와 협동을 통한 원격제어는 필수적이라 할 수 있다. 현재 지도 작성이 가능한 청소로봇은 바닥에 센서를 부착하거나 작업환경에 카메라 및 기타 많은 장치를 구축하므로 고가의 장비로 분류되어 일반적으로 활용지 못하고 있다. 본 연구에서는 청소로봇의 효율적인 제어를 위하여 작업환경에서 로봇의 궤적과 센서정보를 원격으로 서버에 전달하고 서버는 이러한 정보를 바탕으로 지도를 작성하고 최적의 작업을 수행할 수 있는 알고리즘을 연산하여 로봇에 전달할 수 있는 방법을 연구하였다. 이는 로봇이 지도 작성을 위한 연산 과정을 줄이므로 수행 시간을 단축하고 로봇에 주어지는 부하를 줄일 수 있다. 또한 원격으로 제어를 수행하므로 무선통신이 가능한 각종 디바이스와 상호 연동할 수 있는 체계를 만들어 유비쿼터스 환경을 구축할 수 있는 계기를 만들므로 청소로봇의 성능이 향상될 수 있음을 보인다. 본 연구에서는 청소로봇을 제작하고 시뮬레이션과 실험을 통하여 전체적으로 주어진 작업을 효율적으로 수행할 수 있음을 보여준다.

• The Journal of the Korea Contents Association
• /
• v.19 no.6
• /
• pp.179-191
• /
• 2019

It is not easy to predict the return on investment in the content business, and there is no index to evaluate cast & crew. The absolute number of TV ratings is steadily declining, but there is no substitute index yet. In this study, we tried to predict the relative popularity of the drama by designing the relative superiority of the individual drama viewership as the response variable and designing the relative superiority of the drama participants as the explanatory variables. We used various machine learning algorithms and added explanatory variables that were found to be useful in previous studies. As a result, with properly combined explanatory variables, a high prediction accuracy of 84% is obtained. In this study, we intend to promote the investment efficiency of the entire contents industry by predicting the relative popularity of the contents.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.28 no.3A
• /
• pp.323-330
• /
• 2008

The ship collision analysis of steel pile group as protection system of bridge in navigable waterways was performed to analyze the structural characteristics of protective structure during ship collision. The analysis encompassed finite element modeling of ship and pile, modeling of material non-linearity, hard impact analysis, displacement-based analysis and soft impact analysis for collision scenarios. Through the analysis of hard impact with a rigid wall, impact load for each collision type of ship bow was estimated. In the displacement-based analysis the estimate of energy which protection system can absorb within its maximum horizontal clearance so as to secure bridge pier from vessel contact during collision was performed. Soft impact analysis for various collision scenarios was conducted and the collision behaviors of vessel and pile-supported protection system were reviewed for the design of protection system. The understanding of the energy dissipation mechanism of pile supported structure and colliding vessel would give us the optimized design of protective structure.

• Journal of Intelligence and Information Systems
• /
• v.10 no.2
• /
• pp.147-163
• /
• 2004

For the purchase of a cheaper product on the Internet, many customers have been trying to search online shopping mall sites and visit comparison-pricing shops that compare prices and other criteria of the product. Others have been participating into online auction markets or group-buying markets. However, a lot of online shopping malls, auction markets, and group-buying markets provide the same product with different prices. Since these marketplaces have different price settlement mechanism, it is very difficult for the customers to determine marketplace to purchase, considering different kinds of marketplaces at the same time. To overcome such limitations, decision rules and solution procedures for purchase decision making are necessary, which can cover multiple marketplaces simultaneously. For this purpose, purchase decision making in each market must be conducted to maximize customer's utility, and conflicts with other marketplaces must be resolved. Therefore, we have developed the rules and methods that can negotiate cooperatively the purchase decision making in several marketplaces, and designed an architecture of Intelligent Buyer Agent and a message structure to support the idea.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.1
• /
• pp.719-727
• /
• 2021

In the field of architecture, retractable devices capable of responding flexibly to the environment have been applied widely to large structures. Among these devices, the aesthetically pleasing retractable membrane is lightweight so that the membrane can be opened easily using only a traction device. On the other hand, because the towed membrane moves as it is connected to the main cable by a trolley, the number of trolleys needed increases in proportion to the roof's area. This study proposes an optimal model for an open-type trolley (OTT), which is used widely in these devices, using topology optimization. The analysis used the ANSYS program. A new model was proposed based on the results and reviewed through the feedback. Through this process, it was possible to develop a prototype with increased durability and reduced weight. For OTT, optimization was performed based on static analysis and the boundary conditions, so three prototypes were designed. A comparison of the proposed trolley with the conventional one under the same conditions revealed an up to 71.04% decrease in volume while the yield-strength reached 8.67 to 11.43%. In conclusion, the optimal trolley proposed was found to be reliable in terms of economy and stability.