• 품질경영학회지
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• 제26권1호
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• pp.99-107
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• 1998

This paper presents a software reliability model that is based on a nonhomogeneous poisson process. The major contribution of this model is combining multiple failure types with imperfect debugging by use of S-shaped mean value function. The software reliability model allows for three different types of errors: Critical errors are the most difficult to detect and the most expensive to remove. Major errors are moderately difficult to detect and fairly expensive to remove. Minor errors are easy to detect and inexpensive to remove. The model also allows for the introduction of any of these types of errors during the removal of an error. A numerical example is provided to illustrate the above techniques.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권7호
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• pp.2377-2389
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• 2022

At present people have higher and higher requirements for network video quality, but video quality will be impaired by various factors, so video quality assessment has become more and more important. This paper focuses on the video quality assessment method using different fuzzy neural networks. Firstly, the main factors that impair the video quality are introduced, such as unit time jamming times, average pause time, blur degree and block effect. Secondly, two fuzzy neural network models are used to build the objective assessment method. By adjusting the network structure to optimize the assessment model, the objective assessment value of video quality is obtained. Meanwhile the advantages and disadvantages of the two models are analysed. Lastly, the proposed method is compared with many recent related assessment methods. This paper will give the experimental results and the detail of assessment process.

• 제어로봇시스템학회논문지
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• 제12권12호
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• pp.1163-1168
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• 2006

Manufacturing technology for the production of high value-added fine chemical products is emphasized and getting more attention as the diversified interests of customers and the demand of high quality products are getting bigger and bigger everyday. Thus, the development of advanced batch processes, which is the preferred and most appropriate way of producing these types of products, and the related technologies are becoming more important. Therefore, high-precision batch distillation is one of the important elements in the successful manufacturing of fine chemicals, and the importance of the process operation strategy with quality assurance cannot be overemphasized. Accordingly, proposing a process structure explanation and operation strategy of such processes including batch processes and batch distillation would be of great value. We investigate optimal operation strategy and production planning of multi-purpose plants consisting of batch processes and batch distillation for the manufacturing of fine chemical products. For the short-term scheduling of a sequential multi-purpose batch plant consisting of batch distillation under MPC and UIS policy, we proposed a MILP model based on a priori time slot allocation. Also, we consider that the waste product of being produced on batch distillation is recycled to the batch distillation unit for the saving of raw materials. The developed methodology will be especially useful for the design and optimal operations of multi-purpose and multiproduct plants that is suitable for fine chemical production.

• 품질경영학회지
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• 제37권4호
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• pp.1-9
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• 2009

Supplier selection process is one of the most important arenas of production and logistics management for many companies. This study explores the application of the analytic network process (ANP) approach for the evaluation of suppliers based on several different evaluation criteria. The ANP approach in this study is capable of providing priorities of suppliers that capture network relationships among several evaluation criteria which are not independent. Therefore this study provides value to practitioners by providing a generic model for supplier selection. In addition, for researchers, it demonstrates further research possibilities for more complex decision making problems using ANP.

• 국제학술발표논문집
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• The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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• pp.453-458
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• 2011

The construction industry's importance to nation building, economic empowerment, and contributions to global commerce cannot be over emphasised. However, poor productivity, accidents, rework, time and cost overruns, and client dissatisfaction have characterised the industry performance in a multi-dimensional way. The central issue in this particular research is the seemingly inadequate achievement of optimum performance in the construction process, either with respect to value for money for the client and the entire construction supply chain or value in terms of the utility derived from built assets in spite of efforts by government and governmental bodies such as the Construction Industry Development Board (cidb) to increase industry performance. Therefore, based upon an extensive review of related literature, the paper reports on effects and causes of non-value adding activities in the construction industry in general, and South African construction in particular. The research findings indicate that activities that can be referred to as non-value activities are not only prevalent, but they can also be held responsible for performance related issues in terms of cost, time, quality and health and safety (H&S) in construction; and the exploration of pluralism in the research methodology may result in a robust model based upon the system dynamics approach. Therefore, the study suggests that there is major scope for value optimisation in the construction process especially in terms of availability and implementation of interventions, which have not only proven successful in other industries, but are also adaptable in the construction industry context.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2007년도 추계학술대회 및 정기총회
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• pp.488-492
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• 2007

In this study, we investigated how to distinguish customer delivered value to re-purchasing in fierce B2C industry. To identify key managerial variables that could distinctively impact re-purchasing, we first identified customer value proposition as per the customer buying decision process. Next, core value propositions of choice efficiency and competitive price are defined to determine vendor satisfaction during the searching stage and purchasing stage. The trust level is also introduced in the sense of reflecting confirmation to guarantee after purchase security. Then, significant managerial variables to impact on core value propositions are extracted. The resulting structural model illustrated that search convenience and quality assurance affect the choice efficiency, and re-purchase intention is strongly explained by both the vendor satisfaction and trust level. The empirical testing results also support that transaction cost reduction is key determinant of shopping at the Internet shopping mall. Furthermore, trust level should be combined to induce re-purchasing in addition to transaction cost savings.

• Journal of Construction Engineering and Project Management
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• 제1권3호
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• pp.38-44
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• 2011

The central issue in this particular research is the seemingly inadequate achievement of optimum performance in the construction process, either with respect to value for money for the client and the entire construction supply chain or value in terms of the utility derived from built assets in spite of efforts by government and governmental bodies such as the Construction Industry Development Board (cidb) to increase industry performance. Therefore, based upon an extensive review of related literature, the paper reports on effects and causes of non-value adding activities in the construction industry in general, and South African construction in particular. The research findings indicate that activities that can be referred to as non-value activities are not only prevalent, but they can also be held responsible for performance related issues in terms of cost, time, quality and health and safety (H&S) in construction; and the exploration of pluralism in the research methodology may result in a robust model based upon the system dynamics approach.

• 한국해양공학회지
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• 제21권5호
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• pp.18-24
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• 2007

The environmental value of coastal vegetation has been widely recognized. Coastal vegetation such as reed forests and seaweed performs several useful functions, including maintaining water quality, supporting fish (and, thus, fisheries), protecting beaches and land from wave attack, stabilizing sea beds and providing scenic value. However, studies on the physical and numerical process of wave propagation, sediment transport and bathymetric change are few and far between compared to those on the hydrodynamic roles of coastal vegetation. In general, vegetation flourishing along the coastal areas attenuates the incident waves through momentum exchange between stagnated water mass in the vegetated area and rapid mass in the un-vegetated area. This study develops a numerical model for describing the wave attenuation and sediment transport in a wave channel in a vegetation area. By comparing these results, the effects of vegetation properties, wave properties and model parameters are clarified.

• 오토저널
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• 제5권3호
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• pp.45-55
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• 1983

This paper discussed about Application Technique of Numerical Methods for large structure. The dynamic behaviours of a vehicle were investigated through finite element modelling. After dividing a vehicle body into three substructures, Basic Mass System was composed of 60 flexual modes which was obtained from the dynamic characteristics of each substructure using Modal Synthesis Method. Engine, transmission and rear axle, etc. were added to Basic Mass Model, consequently Full Mass System was constructed by 72 degree of freedoms. Full Mass System was analyzed over the frequency range 0.5-50.0 Hz under the loading conditions which were Stationary Gaussian Random Process. Results and discussions provided the guidelines to eliminate resonances among the parts and to improve the Ride Quality. The Absorbed Power was used as a standard to determine the Ride Quality. The RMS value of driver's vertical acceleration was obtained 0.423g from the basic model and 0.415g from the modified model.

• 융합보안논문지
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• 제8권1호
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• pp.101-108
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• 2008

본 연구에서는 항만 물류 프로세스의 현황과 장애요인을 분석하고, Lean이론을 적용한 프로세스의 재설계를 통해 이를 개선하기 위한 방안을 도출하는 한편, 개선된 프로세스를 통한 항만물류시스템을 구축하기 이전 과정을 철강기업 내에 특화된 부두 운영 업무 중 슬라브 관리업무에서 항만물류프로세스의 관련 주체를 선별하고 각 주체간의 관계를 파악하여 부두, 조업, 출하, 공정, 품질, 구매에 이르는 관리업무를 정의하고 각각 개체사이의 정보와 슬라브의 흐름에서 Lean 도구를 사용하여 기존 프로세스 상에 Value added와 Non-Value added를 분석하여 Cycle Time의 감소, 재고감소, 업무전환시간의 감소, 재작업감소, 서비스개선, 낭비 감소 등을 목표로 업무프로세스를 정형화시키고, 항만현장이 항만물류프로세스를 최적의 상황으로 실행 할 수 있도록 환경의 재설계를 통한 항만물류프로세스의 개선된 모델을 제시한다.