• Atmosphere
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• v.32 no.2
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• pp.87-101
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• 2022

In this paper, the performance improvement for the new KMA's Climate Prediction System (GloSea6), which has been built and tested in 2021, is presented by assessing the bias distribution of basic variables from 24 years of GloSea6 hindcasts. Along with the upgrade from GloSea5 to GloSea6, the performance of GloSea6 can be regarded as notable in many respects: improvements in (i) negative bias of geopotential height over the tropical and mid-latitude troposphere and over polar stratosphere in boreal summer; (ii) cold bias of tropospheric temperature; (iii) underestimation of mid-latitude jets; (iv) dry bias in the lower troposphere; (v) cold tongue bias in the equatorial SST and the warm bias of Southern Ocean, suggesting the potential of improvements to the major climate variability in GloSea6. The warm surface temperature in the northern hemisphere continent in summer is eliminated by using CDF-matched soil-moisture initials. However, the cold bias in high latitude snow-covered area in winter still needs to be improved in the future. The intensification of the westerly winds of the summer Asian monsoon and the weakening of the northwest Pacific high, which are considered to be major errors in the GloSea system, had not been significantly improved. However, both the use of increased number of ensembles and the initial conditions at the closest initial dates reveals possibility to improve these biases. It is also noted that the effect of ensemble expansion mainly contributes to the improvement of annual variability over high latitudes and polar regions.

• Journal of Distribution Science
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• v.13 no.11
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• pp.111-121
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• 2015

Purpose - This study's purpose is to investigate the impact of supply chain management (SCM) factors among targeted Korean distribution firms. Antecedents are established for supply chain orientation (SCO) for the management and organization of cultural assets. The research sets up SCO corresponding to management cultural assets and to organizational factors in the results. The research model is created to examine the SCO based on a strategic perspective and the operational performance of the SC and SCM. In addition, an integrated model is constructed to analyze the moderating effect by setting partner cooperation as a relational capital factor. The main aim of this study is to analyze the characteristics of the supply chain structure as a source of competitive advantage for distribution service firms participating in the supply chain. In the moderating effects analysis, the role of partner cooperation as relational capital is examined in detail. Research design, data, and methodology - The study examined the existing research related to supply chains, discussing the antecedents of the performance of SCM and SCO. SCM was established with the partner's cooperation as relational capital. Including the moderating effects of the partner cooperation, the research proposed a seven hypotheses path analysis model. The samples were collected from the Korean export enterprises in the distribution service sector, with 185 samples selected for the final analysis. To try and measure the four latent variables presented in the analysis model based on existing studies, 22 measurement items were used. The empirical analysis used the appropriate PLS (partial least squares) method on the path analysis reliability and validity and for common method bias. After testing the seven hypotheses, the research tested the moderating effects to the path analysis. Using PLS as structural equation modeling, the seven hypotheses were tested including the moderating effects of the partner relational capital on the 185 samples. Results - In the results, the SCO had a positive impact on both SCM and the relational capital of partner cooperation. The SCM had a significant impact on the operational performance of the SC. Further, partner cooperation also had a significant impact on SCM and the operational performance of the SC. The moderating effect analysis of the SCM and partner cooperation found a significant impact on the operational performance of the SC. On the other hand, the moderating effect of the SCO and partner cooperation did not affect the SCM. Conclusion - The results of this research show that the existing supply chain-related research can be applied to the operational performance of the SC for a Korean distribution service firm. In view of the fact that SCO is a source of competitive advantage, it should be taken into account when a firm wants to improve the performance of the SCM of the distribution service. This is because it can be assumed that SCO plays a role in supply chain management for the distribution firm.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.507-513
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• 2004

In the railway system, transportation plan corresponds to a m aster plan for transport services. This service plan must be constructed to minimize operational cost or maximize revenue considering transportation demands and resource capacities in the railway operation company, and it includes several sub-planning activities such as train operation frequency plan, train (schedule) plan, train capacity assignment plan, and rolling stock requirement plan. In these sub- planning processes, train can be con side red as a product for providing customer services, and customer demands and operational advantages must be considered. In this paper, we present an effect estimation system for the train capacity pattern in a train schedule, and the effect of capacity pattern can be expressed as minimum spilled demand, minimum train service cost, and maximum train revenue or profit.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.349-352
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• 1999

In this paper, we present simplified fault set which is made by analyzing fault relation to design specification in CMOS operational amplifier. The hard fault is easily modeled because an effect of hard fault is out of all design specification. However, the soft fault is not easily modeled because an effect of soft fault on design specification is varied according to position and depth of fault. We simulated hard and soft fault by HSPICE, varying threshold voltage and W/L ratio from 90% increase to 90% decrease. The decrease of test time and the production of high reliability mixed-mode IC are possible by the proposed fault set.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.6
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• pp.143-154
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• 2018

This study is intended to look into the effects of SCM(supply chain management) competency and process improvement on operational performance in small and venture companies. To achieve this, a survey was empirically carried out to 179 small and venture manufacturing companies. The findings showed that the SCM competency had a significant effect on the process improvement and operational performance in small and venture companies, adopting all hypotheses. And the process improvement had a significant mediating effect on the relationship between SCM competency and operational performance in small and venture companies, adopting hypothesis 4. As for the findings, strategic alliance, technology development, competency concentration as SCM competencies and starting preparation, detailed planning, implementation management as process improvements were factors that have positive effects on quality performance, cost reduction and profit increase as operational performances in small and venture companies. In other words, the better process and performance by the maximized SCM competencies require selective input strategies for strategic alliance, technology development and competency concentration in small and venture companies. And for its early application and settlement, the starting preparation and detailed planning of business process within small and venture companies need to be jointly put in action under clear company-wide goal management. Consequently, the expected performance can be maximized when strict management and implementation lead to these attributes.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.6D
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• pp.623-636
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• 2012

Roundabout is an intersection that allows vehicles to pass through the intersection by circulating the circular traffic island at the center of the intersection. In this study, a comparative analysis was conducted on roundabout at five locations in order to deduce the operational result and financial effect of roundabout and signal intersection. As for the operational result, it was found that roundabout showed improvement effect in the average delay per vehicle compared to that of signal intersection by minimum of 65.6% and maximum of 91.77%. it was found that roundabout showed financial cost-saving effect in the traffic congestion cost compared to that of signal operation by minimum of 58.59% and maximum of 81.69% per year. It can be known from these analysis results that roundabout has significant operational effects under certain amount of traffic volume by allowing vehicles to pass through the intersection in a continuous way without much waiting time and stoppage from signal control.

• Journal of Digital Convergence
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• v.9 no.6
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• pp.153-163
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• 2011

This study analyzes the military and political factors that influenced the Participatory Government's resolution in Wartime Operational Control (OPCON) Transition. The research on key factors in OPCON transition firstly implemented literature research and then increased feasibility through additional use of AHP. The analysis results showed that there was a negative effect for Korean Peninsular Defense in the 'ROK-US Alliance Asymmetry' area, a positive effect to increase ROK-led Capability of Theater Operation in the 'ROK and U.S. Alliance Interdependence' area and a positive effect for Invocation of ROK Self-Defense Power in the 'Interests of Participatory Government's Liberal Regime' area respectively. After applying AHP, "ROK exercise of Self-defense" in the 'Interests of Participatory Government's Liberal Regime' area received the highest assessment, while the "Increasement of North Korea's Threat" in the 'ROK-US Alliance Asymmetry' area received the lowest assessment. This study is meaningful in that it analyzed the key military and political factors in the Participatory Government's resolution of Wartime OPCON Transition using AHP.

• Journal of Korea Port Economic Association
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• v.27 no.3
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• pp.13-39
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• 2011

Many previous studies on the subject of supply chain have consistently claimed that they need collaboration among the partners of supply chains in order to enhance supply chain performance. The purpose of research is to examine the causal linkages among relational characteristics, collaboration, performance in the logistics firm and this research focuses on two types collaboration(operational collaboration and strategic collaboration) as the mediation variable between relational characteristics and supply chain performance. To test the above research questions, we collected data from logistics firm(N=164). The proposed structural model was tested using the PLS(Partial Least Square) statistical program. The research results are as follows. Trust, and information sharing have positive influences on operational collaboration, and operational collaboration have also positive influences on supply chain performance. Duration and information sharing have positive influences on strategic collaboration. However, strategic collaboration has non-positive influences on supply chain performance. The effect of relational characteristics on supply chain performance is mediated by operational collaboration.

• Journal of the Korean earth science society
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• v.29 no.7
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• pp.567-578
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• 2008

The extratropically transitioning cyclones have been shown to have a large effect on weather system in the midlatitues and cause sometimes the severe weather phenomena. However, both operational forecasting and research aspect of ET remain a significant challenge. Because it is difficult to distinguish ET stage due to obscure configuration of the cyclone itself. Furthermore, any definition of ET should not only be precise enough to satisfy the needs of the operational and research communities. Therefore, the "operational deterministic process for ET" was proposed and has been used to diagnose both structure and subsequent process of ET in 2007. In this study, it has been examined the maximum wind and SST in the 1st step, satellite image in the 2nd step, sounding in the 3rd step, surface weather chart analysis in the final step. This operational manual has allowed better monitoring and understanding of the changes in the structure as ET occurs.

• Atmosphere
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• v.31 no.5
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• pp.511-523
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• 2021

This study explores the optimal ensemble size to improve the prediction performance of the Korea Meteorological Administration's operational climate prediction system, global seasonal forecast system version 5 (GloSea5). The GloSea5 produces an ensemble of hindcast data using the stochastic kinetic energy backscattering version2 (SKEB2) and timelagged ensemble. An experiment to increase the hindcast ensemble from 3 to 14 members for four initial dates was performed and the improvement and effect of the prediction performance considering Root Mean Square Error (RMSE), Anomaly Correlation Coefficient (ACC), ensemble spread, and Ratio of Predictable Components (RPC) were evaluated. As the ensemble size increased, the RMSE and ACC prediction performance improved and more significantly in the high variability area. In spread and RPC analysis, the prediction accuracy of the system improved as the ensemble size increased. The closer the initial date, the better the predictive performance. Results show that increasing the ensemble to an appropriate number considering the combination of initial times is efficient.