• Journal of the Society of Naval Architects of Korea
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• v.44 no.3 s.153
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• pp.340-347
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• 2007

Main purpose of the study is to develop a transit model for icebreaking cargo vessels in the Northern Sea Route and to select optimum sea routes with the shortest navigation time and the lowest operation cost. This numerical model executed with basic information such as ship capabilities, transit directions and months of transit, can calculate total transit distance and elapsed time, mean speed, operation cost for each vessel. In the transit model. environment information such as the site-specific ice conditions, wave and wind states are utilized for four different months (April, June, August, and October) along the Northern Sea Route. The model also defines a necessary period of an icebreaker escort. Then the optimum sea routes are selected and visually displayed on the digital map using a commercial software ArcGIS. Usefulness of the selected sea routes is discussed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.4
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• pp.1239-1247
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• 2010

In this paper, we were researched decision problem called an optimal release policies after testing a software system in development phase and transferring it to the user. The applied model of release time exploited infinite failure non-homogeneous Poisson process This infinite failure non-homogeneous Poisson process is a model which reflects the possibility of introducing new faults when correcting or modifying the software. The intensity function used Gompertz, Preto and Log-logstic pattern which has the efficient various property. Thus, optimal software release policies which minimize a total average software cost of development and maintenance under the constraint of satisfying a software reliability requirement becomes an optimal release policies. In a numerical example, after trend test applied and estimated the parameters using maximum likelihood estimation of inter-failure time data, estimated software optimal release time.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.8
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• pp.1903-1910
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• 2009

In this paper, we were researched decision problem called an optimal release policies after testing a software system in development phase and transferring it to the user. The applied model of release time exploited infinite failure non-homogeneous Poisson process This infinite failure non-homogeneous Poisson process is a model which reflects the possibility of introducing new faults when correcting or modifying the software. The failure life-cycle distribution used the Weibull distribution which has the efficient various property which has the place efficient quality. Thus, optimal software release policies which minimize a total average software cost of development and maintenance under the constraint of satisfying a software reliability requirement becomes an optimal release policies. In a numerical example, after trend test applied and estimated the parameters using maximum likelihood estimation of inter-failure time data, estimated software optimal release time.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.8
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• pp.3689-3700
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• 2016

It is not practically feasible to apply hardware-based fault-tolerant schemes, such as hardware replication, in mobile devices. Therefore, software-based fault-tolerance techniques, such as checkpoint and rollback schemes, are required. In checkpoint and rollback schemes, the optimal checkpoint interval should be applied to obtain the best performance. Most previous studies focused on minimizing the expected execution time or response time for completing a given task. Currently, most mobile applications run in real-time environments. Therefore, it is extremely essential for mobile devices to employ optimal checkpoint intervals as determined by the real-time constraints of tasks. In this study, we tackle the problem of determining the optimal inter-checkpoint interval of checkpoint and rollback schemes to maximize the deadline meet ratio in real-time systems and to build a probabilistic cost model. From this cost model, we can numerically find the optimal checkpoint interval using mathematical tools. The performance of the proposed solution is evaluated using analytical estimates.

• Journal of Information Technology Applications and Management
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• v.9 no.3
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• pp.113-127
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• 2002

The effort for software process improvement is lately surging its interest though it does not satisfy both developer and receiver In terms of low productivity, quality, delay and increasing cost. According to current research, software process improvement contributes to improvement of productivity, its Duality, reduction of development time and cost, and the prediction of the time limit for delivery, which means software process improvement affects competitive advantage among developers. The latest research is whether the investment for information technology substantially had effect on improvement of productivity. That is, software process improvement and maturity of software industries has influence upon economic efficiency and as a result, it plays an important role in whole industries. This research is that how does software process improvement using CMM (Capability Maturity Model) and SPICE (Software Process Improvement and Capability dEtermination) have a effect on factors of software engineering, and how does it have influence upon competitive advantage among SI firms. For this research, reusability, customizability, participation, and review & inspection are set to independent variable and process flexibility and process predictability are set to mediate Variable. Finally, competitive advantage among SI firms Is set to dependent variable. The targets for survey are laborers who work for SI firms. The result of this research is as follows: 1 ) Reusability, Customizability and participation is not rejected but review and Inspection is rejected in process flexibility which has significant level 0.05. 2) Reusability, Customizability and participation is not rejected but review and inspection Is rejected in process predictability which has significant level 0.05. 3) Process flexibility is not rejected and process predictability Is rejected in the competitive advantage of 51 industries which has significant level 0.05

• Current Industrial and Technological Trends in Aerospace
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• v.9 no.1
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• pp.110-118
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• 2011

In this paper, design techniques and technological trends applied on simulator development, which are based on Model Driven Architecture, are described. The methodology, process and modeling support tools for development of simulation software are introduced with both satisfaction of user's requirements and benefit to simulator developers of reducing cost. In addition, contents in ECSS standard for reusability of simulation model and its usages applied on industries are presented and major features of current technological changes with highlights of key-word are discussed.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2015.07a
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• pp.171-172
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• 2015

Vinalines is actually known as not only one of Vietnam's state-sponsored economic giants but also the largest shipowner by tonnage in Vietnamese shipping industry. Therefore, a question of how to improve business performance of the corporation is always received deep attention by Vietnamese government, specially after the seriously economic scandal of Vinalines in a last few years. Among development strategies, the study focuses on short-term one in which Vinalines is recommended to restructure its own fleet in order to optimize performance of fleet operation and minimize costs while meeting the customer's shipping demand in near future. The first section is of introduction. Via method of statistical data analysis, section 2 brings to readers a panorama about the development profile and the current situation of development of Vinalines. In section 3, the authors use linear programming for setting a cost-minimization model optimizing Vinalines fleet structure based on available statistics and forecast information by Vinalines. The optimization problem is solved by applying AIMMS software in section 4. Finally, some conclusions and proposals by authors for the development of Vinalines are given.

• Journal of Korean Society for Geospatial Information Science
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• v.12 no.1 s.28
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• pp.79-85
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• 2004

The GIS(Geographic Information System) projects require big initial investment and cost of maintenance. Decision makers would not launch GIS projects unless they are convinced of the benefits of the projects. Therefore the purpose of this paper is to develop an appropriate model for GIS project evaluation. We proposed a GIS project evaluation model and summarize the steps involved in Cost-Benefit Analysis(CBA). The costs of a GIS implementation include hardware and software cost, costs of database development, training expenses, annual maintenance expenses, and other annual expenses. The benefit by using GIS has been assessed into Type I(direct benefits), Type II(indirect benefits), Type III(benefits that result from the sale of information services), Type IV(intangible benefits).

• Journal of KIISE:Software and Applications
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• v.33 no.7
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• pp.605-614
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• 2006

The success of a software development project can be determined by the use of QCD. And as a software's size and complexity increase, the importance of early quality assurance rises. Therefore, more effort should be given to prevention, as opposed to correction. In order to provide a framework for the prevention of defects, defect detection activities such as peer review and testing, along with analysis of previous defects, is required. This entails a systematization and use of quality data from previous development efforts. FMEA, which is utilized for system safety assurance, can be applied as a means of software defect prevention. SW-FMEA (Software Failure Mode Effect Analysis) attempts to prevent defects by predicting likely defects. Presently, it has been applied to requirement analysis and design. SW-FMEA utilizes measured data from development activities, and can be used for defect prevention on both the development and management sides, for example, in planning, analysis, design, peer reviews, testing, risk management, and so forth. This research discusses about related methodology and proposes defect prevention model based on SW-FMEA. Proposed model is extended SW-FMEA that focuses on system analysis and design. The model not only supports verification and validation effectively, but is useful for reducing defect detection.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.4
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• pp.137-146
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• 2016

In recent years, business environment is faced with multi uncertainty that have not been suffered in the past. As supply chain is getting expanded and longer, the flow of information, material and production is also being complicated. It is well known that development service industry using application software has various uncertainty in random events such as supply and demand fluctuation of developer's capcity, project effective date after winning a contract, manpower cost (or revenue), subcontract cost (or purchase), and overrun due to developer's skill-level. This study intends to social contribution through attempts to optimize enterprise's goal by supply chain management platform to balance demand and supply and stochastic programming which is basically applied in order to solve uncertainty considering economical and operational risk at solution supplier. In Particular, this study emphasizes to determine allocation of internal and external manpower of developers using S&OP (Sales & Operations Planning) as monthly resource input has constraint on resource's capability that shared in industry or task. This study is to verify how Stochastic Programming such as Markowitz's MV (Mean Variance) model or 2-Stage Recourse Model is flexible and efficient than Deterministic Programming in software enterprise field by experiment with process and data from service industry which is manufacturing software and performing projects. In addition, this study is also to analysis how profit and labor input plan according to scope of uncertainty is changed based on Pareto Optimal, then lastly it is to enumerate limitation of the study extracted drawback which can be happened in real business environment and to contribute direction in future research considering another applicable methodology.