• Journal of the Korea Computer Industry Society
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• v.2 no.4
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• pp.537-546
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• 2001

Griffth's and LCCMA which are Single-user detection adaptive algorithm are proposed for mitigate MAI(multiple access interference) and the near-far problem in direct-sequence spread-spectrum CDMA system and MOE Algorithm is proposed for MMSE(Minimum Mean-Square Error). This paper pertains to three types of Blind adaptive algorithms which can upgrade system functionality without the requirements from training sequence. It goes further to compare and analyze the functionalities of the algorithms as per number of interfering users or data update rate of the users. The simulation results was that LCCMA algorithm was superior to other algorithms in both areas. Blind application enabled a more flexible network design by eliminating the necessity of training sequence.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.5
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• pp.1145-1149
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• 2008

This paper presents KEPCO research project for developing wide area DAS by reengineering conventional DAS and its functional upgrade. Through the research project system design requirements were prepared based on the local operation status and oversea examples. Application softwares were also developed supporting integrated operation of several area. The system implementation was performed on Choongnam regional head office for pilot operation. The developed wide area DAS will be fully installed on 41 DCC nation wide and expected to contribute on innovation of our distribution network operation.

• Journal of the Korean Magnetics Society
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• v.7 no.6
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• pp.327-333
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• 1997

We designed and constructed the high frequency magnetic characteristics measurement system to measure core loss, B-H curve, permeability of toroidal ferrite core, amorphous core and various materials for high frequency application. The system consists of universal equipments such as digitizing oscilloscope, signal generator, power amplifier, PC in order to make upgrade easily. The power source is composed of waveform synthesizer and power amplifier ranging from DC to 20 MHz, and output signal H and B from sample core are digitized by oscilloscope with sampling rate 1 GS/ s per channel. Computer controls power source and oscilloscope, reads data from oscilloscope, displays analyzed waveform and saves data with file. The entire procedures finishes within few seconds.

• International Journal of Highway Engineering
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• v.14 no.5
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• pp.21-29
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• 2012

PURPOSES: This study is to investigate the mechanical performance of the fiber reinforced lean concrete with respect to different types of fibers. METHODS: Increased vehicle weight and other causes from the exposed conditions have accelerated the deteriorations of road pavement. A new multi-functional composite pavement system is being developed recently in order to extend service life and upgrade the pavement. A variety of tests were conducted before and after hardening of the concrete. RESULTS: From the test results, it was found that the use of different types of fibers did not affect the compressive strength development. This might be due to the inherent property of the lean concrete. When steel fibers were used relatively greater flexural strength and flexural fracture toughness were developed. Also addition of fly ash by replacing a part of Portland cement the fracture toughness was slightly increased. CONCLUSIONS: It has been known that the addition of fibers and use of mineral admixture can be positively considered in the development of multi-functional composite pavement system as its required mechanical performance is obtained.

• Journal of Navigation and Port Research
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• v.26 no.1
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• pp.78-84
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• 2002

In this thesis a shipping broker agent system, which can be executed by a CORBA-based environment using the distributed object technique, CORBA is designed and implemented Nowadays, while the EC system is extensive on the web, legacy host systems have limitations and its capacity-upgrade os required. In order to solve these problems the method that distributes programs into several computer systems can reduce their loads, set low system capacity and minimize network bottleneck. In this thesis using Agent Communication Language(ACL), we propose an agent based prototype and implement an intelligent agent prototype for ships search using CORBA, which can exchange and shiare data between different systems.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.1
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• pp.57-63
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• 2015

Recently, Korea's municipal wastewater treatment plants generated amount of wastewater sludge per day. However, ocean dumping of sewage sludge has been prohibited since 2012 by the London dumping convention and protocol and thus removal or treatment of wastewater sludge from field sites is an important issue on the ground site. The hydrothermal carbonization is one of attractive thermo-chemical method to upgrade sewage sludge to produce solid fuel with benefit method from the use of no chemical catalytic. Hydrothermal carbonization improved that the upgrading fuel properties and increased materials and energy recovery, which is conducted at temperatures ranging from 200 to $350^{\circ}C$ with a reaction time of 30 min. Hydrothermal carbonization increased the heating value though the increase of the carbon and fixed carbon content of solid fuel due to dehydration and decarboxylation reaction. Therefore, after the hydrothermal carbonization, the H/C and O/C ratios decreased because of the chemical conversion. Energy retention efficiency suggest that the optimum temperature of hydrothermal carbonization to produce more energy-rich solid fuel is approximately $200^{\circ}C$.

• Food Science and Preservation
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• v.3 no.1
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• pp.61-75
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• 1996

Apple is most favorable fruit in Korea, and apple farmland has been increased before and after the agreements of Uruguay Round and apple is considered as one of strategic agricultural products. Especially expansion of apple farmland is concentrated in Kyungpook region because of the suitable climate and its market share is about 70 percents in 1992. The marketing channels of apples of Kyungpook region are widely classified by merchant, agricultural or horticultural co-op and large scale farmer's. Among them market share of merchant's occupy over 65 percent. In marketing margins, commercial profit is higher than cost in total marketing margins and, assembler and retailer's margin is not less than wholesaler's. The fluctuation of the price of apple is high in year. The marketing problems of apples are several, first, complex marketing channels, secondly, the high percentage of market share by growing district assembler, thirdly, low rate of package and quality standardization, finally, concentration of shipment of apple because of the shortage of apple processing, storage and marketing facilities, of newly produced apples. In conclusion, to increase apple grower's income with the stabilization of supply and quality upgrade, the improvement measures of marketing system are as follows, first, government level's support in marketing facilities and mechanism, secondly, the increment of supply by grower's cooperatives, thirdly, the establishment of a serious of marketing system to increase the efficiency, fourthly, the establishment of cold-chain system and quality standardization of apple, finally, production of various kinds of apple processing goods.

• Journal of Korea Society of Digital Industry and Information Management
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• v.10 no.1
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• pp.99-104
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• 2014

Nowadays, various researches fulfill in many communication engineering area for B4G (Beyond Forth Generation). Next LTE-A (Long Term Evolution Advanced), MU-MIMO (Multi-User Multi Input Multi Output) method raises to upgrade throughput performance. However, the method of user selection is not decided because of many types and discussions in MU-MIMO system. Many existing methods are powerful for enhancing performance but have various restrictions in practical implementation. Fairness problem is primary restriction in this area. Existing papers emphasis algorithm to increase sum-rate but we introduce an algorithm about dealing with fairness problem for real commercialization implementation. Therefore, this paper introduces new user selection method in MU-MIMO system. This method overcomes a fairness problem in SUS (Semiorthogonal User Selection) algorithm. We can use the method to get a similar sum-rate with SUS and a high fairness performance. And this paper uses a hybrid method with SC-SUS (Superposition Coding SUS) algorithm and SUS algorithm. We find a threshold value of optimal performance by experimental method. We show this performance by computer simulation with MATLAB and analysis that results. And we compare the results with another paper's that different way to solve fairness problem.

• Electronics and Telecommunications Trends
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• v.32 no.6
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• pp.105-115
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• 2017

This paper describes a project - based quality management model that identifies development technologies and codes while at the same time verifying the ability to implement processes that are essential in R & D projects. In order to verify the process implemented in the R & D project implementation, there are review, checking points, and evaluating methods the process performance levels for five processes such as defining requirements which is the beginning stage of system development, testing process which is the completion stage of system development, and project management and peer review process for project management and support in the proposed project-based quality management model. For development technology and code validation, the model included the documented test cases for each requirement by the developer in the requirements definition stage, debugging and testing in the design and implementation stages, static analysis and open source licence verification procedure, and system environment. After applying the model in SW development R&D project for evaluating the process performance, and verifying the development technology and the code, the developers responded that the improvement in the development technique and the code, and upgrade of process performance level for project are more than 10%.

• The Journal of the Korea institute of electronic communication sciences
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• v.4 no.1
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• pp.7-13
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• 2009

Now society has been extending to ubiquitous information society under the information telecommunication facilities. So it is importance to install and design those for the core business. If there is a serious problem on the information telecommunication infra-facility, it could be seriously effected to the life of the people and the national economy. To prevent the those problems, information telecommunication infra-facilities have been installed/supervised due to the proper telecommunication specialists. In this paper, firstly invested the current supervision system and then proposed how to upgrade information telecommunication services through the proposed supervision system for the telecommunication infra-facilities.