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

• The Transactions of the Korean Institute of Power Electronics
• /
• v.11 no.1
• /
• pp.22-28
• /
• 2006

Establishment of practicalization technologies is becoming more important as dissemination of domestic PV system has been increased. To improve performance through PV system optimization, this paper presents loss factors analysis of PV system based on results of field operational test. Also, as simulation results are compared with actual operational ones, the main loss factors of PV system due to performance degradation are reviewed.

• IE interfaces
• /
• v.25 no.4
• /
• pp.431-440
• /
• 2012

Since pooling is a popular scheme in many areas to attain operational excellence, many researchers investigated the performance of pooling systems. However, rare research could be found on pooling with game situation which has much applicability to real world phenomenon. We analyze the performance of noncooperative pooling system with two servers having different sharing capacity. We investigate the sensitivity of the advantage of capacity pooling on the variation of system parameters, including sharing capacity numbers, pooling probability, pooling strategy and traffic intensity. As a result, we suggest an efficient control policy which facilitate the performance of pooling in a game situation.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.11 no.6
• /
• pp.81-89
• /
• 2008

University Research Centers specialized in defense technology(DURCs) were designed to develop fundamental knowledge and to acquire core technologies related to defense development by conducting creative and interdisciplinary research. The centers also have a function of fostering scientists and practitioners possessing defense-oriented cross-disciplinary knowledges. Since the outset of the DURC in 1994, Sixteen DURCs have been funded and eleven DURCs are now in operation. The purpose of this paper is to analyse the operational status and the performance of DURCs and to suggest ideas on improving the effectiveness of the DURC program by comparing with the Korea Excellent Research Center program and the U.S. National Science Foundation(NSF) Engineering Research Center(ERC) program.

• Journal of the Korea Society for Simulation
• /
• v.3 no.1
• /
• pp.55-63
• /
• 1994

FMS is two or more computer controlled units interconnected with automated workhandling equipment and supervised by an executive computer having random scheduling capabilities. The complex nature of a FMS, coupled with the need to maximize its performance, means that such a system can be effectly designed only by iterative computer simulation methods. At the operational level, simulation had a reduced role to evaluate the performance of planned FMS under a variety of operating strategies. This is probably due to the fact that few simulation models are able to access the current status data of the system. This study reviews the role of simulation for design/operation of FMS and suggests an interface scheme for incorporating a simulation package with a FMS operational database. This scheme can be used for reducing the performance gap between design and real operation of a FMS.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.3 no.1
• /
• pp.66-75
• /
• 2000

The purpose of this study is to develop and illustrate methods of applying trade-off techniques to landing craft air cushion design evaluation. The problem areas of concern are the application of quantitative analytical methods to conceptual design. The interrelationships between composite system measures and selected performance requirements(speed, cruising range, cargo etc.) are analyzed and the expressions for gross weight are developed as functions of performance parameters. Trade-offs of performance parameters in terms of weight are then calculated. The application of these results to evaluation of Require Operational Capabilities are illustrated.

• 한국태양에너지학회:학술대회논문집
• /
• 2012.03a
• /
• pp.494-497
• /
• 2012

A methodology to predict the output performance of small hydro power using treated effluent in wastewater treatment plant has been studied. Existing plant located Kyunggi-Do were selected and the output performance characteristics for these plants were analyzed. As a result, it was found that the developed model in this study can be used to analyze the output characteristics for small hydro power in wastewater treatment plant. Additionally, primary design specifications such as design flowrate, capacity, operational rate and annual electricity production were estimated and discussed.

• Journal of Korean Society for Quality Management
• /
• v.32 no.1
• /
• pp.1-20
• /
• 2004

Six sigma has been the most influential management innovation program since 1996 in Korea. As a result of successful implementation of 6 sigma, there have been a number of dramatic quality improvement cases. However, no empirical study of 6 sigma implementation study has done especially in the service industry of Korea. This article reviews status of finance companies which implemented 6 sigma programs in Korea and then demonstrates the relationship between 6 sigma problem solving tools such as analysis of variance and graph techniques, etc and project success and operational performance. Customer survey tools, process analysis, and documentation tool are identified as influential tools on project success. Tools of measure steps, customer survey tools, and documentation tool are found as influential tools on operational performance.

• Proceedings of the KIEE Conference
• /
• 2007.04a
• /
• pp.23-25
• /
• 2007

The partial distortion elimination (PDE) scheme is used to decrease the sum of absolute difference (SAD) computational complexity, since the SAD calculation has been taken much potion of the video compression. In motion estimation (ME) based on PDE, it is ideal that the initial value of SAD in summing performance has large value. The traditional scan order methods have many operation time and high operational complexity because these adopted the division or multiplication. In this paper, we introduce the new scan order and search order by using only adder. We define the average value which is called to rough average value (RAVR). Which is to reduce the computational complexity and increase the operational speed and then we can obtain the improvement of SAD performance. And also this RAVR is used to decide the search order sequence, since the difference RAVR between the current block and candidate block is small then this candidate block has high probability to suitable candidate. Thus, our proposed algorithm combines above two main concepts and suffers the improving SAD performance and the easy hardware implementation methods.

• International Journal of High-Rise Buildings
• /
• v.6 no.4
• /
• pp.333-343
• /
• 2017

Across the world, building energy codes are becoming stricter, demanding higher levels of energy performance with each issuance. Some locations have taken initiatives to eliminate operational emissions altogether by requiring buildings to be carbon neutral. However, while the objectives of carbon neutrality are without doubt statement worthy, we believe that once operational performance has been tackled to a reasonable level of performance the sights should be trained on a different objective-life; cycle carbon. This paper defines what we mean by life cycle carbon neutrality and presents an approach toward reducing it.