• Journal of the Korean Institute of Navigation
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• v.21 no.2
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• pp.1-9
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• 1997

This paper presented a method of evaluating navigational safety of a ship by means fo the integrted seakeeping performance index(ISPI). The ISPI is defined by measuring only any one factor through the medium of relative dangerousness of the other factors for evaluating seakeeping performance. This evaluation method can be applied to the ships for any types and loading conditions. In devloping the practical evaluation system of navigational safety, it is expected to be useful to solve the difficulties in measuring factors by sensors. The results are also useful for devloping the optimum type of ship by applying at the initial design phase.

• 수도
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• v.22 no.3 s.73
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• pp.120-131
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• 1995

• Proceedings of KOSOMES biannual meeting
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• 2003.05a
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• pp.31-40
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• 2003

There are winds and waves in the sea, and they are changed frequently in accordance with the weather. By analyzing them which have the closest relation to the ship's safe voyage. evaluating the seakeeping performance and then taking a proper action, navigators should carry out safe navigation on the sea. A ship in seaways suffers continuous disturbances by irregular waves, and ship motions with irregular waves cannot be easily described as a system model which is adequate to a control system. But, in general, for seakeeping analysis, ship motions in irregular seas can be estimated by the superposition of the motion responses in regular wave components of the sea spectrum. After comparing and analyzing the winds and waves in major sea areas, this paper evaluates the navigational safety of ships on the Korean coast with potential dangerous seakeeping performance using the weather information provided by land. The conclusion is as follows : (1) It is possible that the safety of ships could be secured more accurately by evaluating the seakeeping performance of ships. (2) When the weather is bad, the departure of ships could be controlled by evaluating the navigational safety of ships. (3) When a ship is placed in commission in any area, this evaluation could be used to decide the type and size of ship in use.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1999.05a
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• pp.171-176
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• 1999

Nondestructive inspection and accompanying life analysis based on fracture mechanics were the major conventional methods for evaluating remaining life of critical high temperature components in power plants. By using these conventional methods, it has been difficult to perform in-service inspection for life prediction. Also, quantitative damage evaluation due to unexpected abrupt changes in operating temperature was almost impossible. Thus, many efforts have been made for evaluating remaining life during operation of the plants and predicting real-time life usage values based on the shape of structures, operating history, and material properties. In this study, a core software for on-line life monitoring system which carries out real-time life evaluation of a critical component in power boiler(high temperature steam headers) is developed. The software is capable of evaluating creep and fatigue life usage from the real-time stress data calculated by using temperature/stress transfer Green functions derived for the specific headers and by counting transient cycles. The major benefits of the developed software lie in determining future operating schedule, inspection interval, and replacement plan by monitoring real-time life usage based on prior operating history.

• Journal of Korean Society for Quality Management
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• v.26 no.3
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• pp.100-107
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• 1998

To evaluate the total quality activities is the most fundamental and critical process as one of the PDCA cycle. The quality award criteria such as Malcolm Baldrige National Quality Award and Deming Award can be a, pp.ied to the guideline for evaluating quality activities. We can identify several important factors for TQM by referring quality award criteria, but they don't suggest how efficiently implement TQM. In this paper, two methodologies are a, pp.ied to evaluate the TQM activities comparatively. One of them is the traditional scoring system (TSS) by analytic hierarchy process (AHP). TSS is the system which evaluates the performance of TQM by the weighted sum of critical success factors. Several quality award system are typical examples of TSS. The other is the efficiency measuring system (EMS) by data envelop analysis (DEA). DEA outperformed other alternative methods to measure the efficiency and it can be a, pp.ied to evaluate the TQM activities. The evaluation system by DEA can be named as EMS. The objective of this paper is to suggest a model called TAE (Total quality management Activities Evaluation), for evaluating TQM activities. In this model TQM organizations are classified into four types by considering TSS and EMS. Those types are high weighted sum and high efficiency type, high weighted sum and low efficiency type, low weighted sum and high efficiency type, and low weighted sum and low efficiency type. Therefore TQM organizations must not only make efforts to get the higher scores in terms of TSS, but also take necessary steps to enhance their efficiencies.

• Journal of Korea Multimedia Society
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• v.20 no.11
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• pp.1741-1749
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• 2017

In commercial digital-cameras, color-filter filters light according to wavelength range of color filter array (CFA) and the filtered intensities contain color information of light. Then, output data of CFA is transformed to final rendered image through demosaicing process. In image processing of digital-camera, the quality of the final rendered image is affected by optical cross talk of CFA, kind of CFA pattern etc. Basically, pattern of CFA plays important role in image quality of final image rendered by digital-camera. Therefore, an evaluation system capable of quantitatively evaluating CFA is needed. This paper proposes a novel evaluation system using existing and proposed image metrics for evaluating CFAs of digital-camera. Proposed CFA evaluation system consist of color difference in CIELAB and S-CIELAB, Structure SImilarity (SSIM), MTF50, moire starting point (MSP), and subjective preference (SP). MSP and SP are newly designed for the proposed evaluation system. Proposed evaluation system is expressed in polar coordinates to analyze the characteristics of CFA objectively and intuitively. Through simulations, we confirmed that proposed CFA evaluation system can objectively assess performance of developed CFAs.

• Journal of the Korean Solar Energy Society
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• v.27 no.2
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• pp.29-35
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• 2007

Monitoring system is constructed for evaluating and analyzing performance of installed 50kW grid-connected PV system and have been monitored since October 2005. As climatic and irradiation conditions have been varied through long-term operation, there is necessity for evaluating numerical values of PV(Photovoltaic) system performance to observe the overall effect of environmental conditions on their operation characteristics. This paper presents performance monitoring results and analysis on component perspective(PV array and power conditioning system) and global perspective(yield, losses) of PV system for one year monitoring periods.

• Journal of KIISE:Information Networking
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• v.37 no.6
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• pp.494-498
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• 2010

Performance requirements of a system are usually closely related to the quality of service provided by the system. The call success rate of a mobile communication system is, for example, directly linked with the quality of call service. Therefore, meeting the performance requirements is one of the critical issues during the operation of services as well as in system development. In this paper, we present a testing method for evaluating the call success rate of a mobile communication system by using interval estimation. Also we analyze the criterion used in the evaluation of the quality of 3G mobile communication services which was recently performed by Korea Communications Commission and then discuss the problems.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.6
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• pp.596-604
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• 2005

This paper presents the work on evaluating the LCC (Life-Cycle Cost) of a heat pump system as unutilized energy system. The river water as an unutilized energy source was used for the heat source of heat pump system. LCC analysis is a concrete method for evaluating the economical efficiency of energy facilities of building. The present case study shows an example of adequate use of the LCC analysis on a heat pump system and conventional gas boiler and refrigerator for building heat supply. A life cycle of 20 years was used to calculated net present value of energy cost. Over a 20 year life cycle, the energy cost could be reduced by 612 million won if a heat pump system were used instead of a conventional boiler and an absorption refrigerator.

• Proceedings of the KIEE Conference
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• 1997.07c
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• pp.1118-1120
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• 1997

This paper presents a simple method for evaluating of voltage stability using the line flow equation. Line flow equations ($P_{ij}$, $Q_{ij}$) are comprised of state variable, $V_i$, ${\delta}_i$, $V_j$ and ${\delta}_j$, and line parameter, r and x. Using the feature of polar coordinate, these becomes one equation with two variables, $V_i$ and $V_j$. Moreover, if bus j is slack or generater bus, which is specified voltage magnitude, it becomes one equation with one variable $V_i$, that is, may be formulated with the second-order equation for $V_i^2$. Therefore, multiple load flow solutions may be obtained with simple computation, and the formulated equation used for approximately evaluating of voltage stability limit considering line flow sensitivity. The proposed method was validated to 2-bus and IEEE 6-bus system.