• Journal of Digital Convergence
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• v.12 no.12
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• pp.329-335
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• 2014

In this paper, to improve the performance of PB/MC-CDMA system, we have researched about the decision feedback channel estimation method using the pilot symbol with data symbol. The PB/MC-CDMA system is able to obtain the improved BER by frequency diversity gain and frequency domain equalizer in the frequency selective fading channel. However, when it is not the estimating of channel exactly, it is degrading the performance of BER in the system for occurred the interference among users. To improve the performane system in the multi-user environment the proposed system is using the decision feedback to estimate channel using the channel estimated value of the first stage and second stage. The proposed system is evaluated by computer simulation. The proposed system is not only able to improve the performance of BER by decreasing the interference to each user, but also the proposed system is possible to reduce number of pilot symbol to estimate the channel. Therefore, it confirmed the proposed system improves the performance than the conventional system.

• Journal of the Earthquake Engineering Society of Korea
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• v.2 no.2
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• pp.45-55
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• 1998

Although a number of methods have been proposed to predict the liquefaction potential, few methods have been developed by using the characteristic of material's microstructure. In this research, fundamental procedure is proposed for the assessment of liquefaction potential in saturated soils based on the Disturbed Sate Concept(DSC) model which can provide a unified constitutive model for the characterization of entire stress-strain behavior under cyclic loading. From this concept, the value of disturbance at threshold state (Critical Disturbance, $D_C$) in the deforming microstructure provides the basis for initial liquefaction. This method is verified with respect to data from Cyclic Truly Triaxial test for saturated Ottawa sand. Also, the relationship between liquefaction and initial confinig stress is defined using definition of $D_C$. It is believed that the new procedure for identifying liquefaction based on the DSC model can capture the behavior of liquefation, and as a result, it is shown to be on improvement over the available empirical procedures.

• Korean Journal of Agricultural Science
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• v.32 no.2
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• pp.107-126
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• 2005

The most limited production resource in Korea is land. During the period from 1995 to 2002, annual farm land area of 17,600ha have been converted to urban and industrial land. The self-sufficiency rate of rice, Korean staple food, is expected to be decreased from 97.5% in 2003 to 60-70% in 2020. Under such conditions, this study is aimed at first identifying multi-functional benefits of the reclamation projects such as agricultural production, industrial water supply, urban land supply, transportation effects, sightseeing effects and environmental values with and without the projects. To carry out the objectives, three existing tideland reclamation projects such as Daeho, Kumgang and Yongsangang irrigation project stage II were evaluated and Saemangeum tideland reclamation project which was jointly revaluated by environmental NGO and Govn't appointed specialists in 2000 was reviewed. According to this study results, tide land reclamation projects were showed financially and economically feasible and environmentally sustainable. The joint cost like estuary dam should be allocated based on the multi-functional benefits of the projects. To allocate the joint cost, legal and institutional improvement should adapt the joint cost allocation method as the specific cost-remaining benefit method. Korea has more than 402,000 ha of tidal flat of which 76,396ha have been reclaimed in 2003. To meet food security and to cope with shortage of land, phil-environmental reclamation projects should be continuously implemented and necessary tidal flats for protecting environmental ecosystem should be remained according to the detail survey results of reclaimable resources.

• Proceedings of the Korean Geotechical Society Conference
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• 2007.09a
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• pp.623-634
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• 2007

The aim of this research is development and verification of resistivity seismic dilatometer (RSDMT) system. The resistivity module for obtaining resistivity-depth plot and seismic module for obtaining wave velocity-depth plot are attached to the conventional flat dilatometer testing equipment. To enhance reliability and repeatability of seismic part in RSDMT, automatic testing system including automatic surface source, PC based data acquisition system and operating program were developed. To obtain real resistivity value of soil, geometric factor for the array of electrodes in RSDMT was derived empirically. The verification studies for the developed RSDMT system were performed at the southeast side of Korea where soil improvement work is planned. SPT, CPT, geophysical subsurface imaging techniques and some laboratory tests were performed for the comparisons. As one penetration of RSDMT, various soil parameters could be obtained. The results of field test showed good repeatability and reliability in every part. From these studies, developed RSDMT system was checked and the effectiveness of this system was verified in light of proper evaluation of geotechnical characteristics of soft soil.

• Proceedings of the Korean Geotechical Society Conference
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• 2007.09a
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• pp.603-610
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• 2007

It is well known that the standard penetration test (SPT) has been used in all over the world to get geotechnical properties of the ground. However, it is difficult to apply the SPT to the dense sand, gravel, weathered rock, etc. For the application of the SPT in these grounds, it is necessary to change in the diameter and the impact energy of the SPT. For the improvement of site investigation technology, Large Penetration Testing device (KICT-type LPT) was developed and applied to the in situ condition. The drop height and weight of the hammer in developed system were decided as 760 mm and 150 kg, respectively. Semi-auto hammer drop system identical with KS F2307 and JI A1259S was adopted. And the developed sampler has the inner diameter of 63 mm and the length of 500 mm with the adjustment of energy ratio to the SPT of 1.5. The hammer energy level was measured during the performance of the KICT-type LPT using SPI system (quality control system from driven piles).

• Culinary science and hospitality research
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• v.12 no.3 s.30
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• pp.151-163
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• 2006

The sauce is very important to western dishes and also to value and relish of dishes because taste, appearance and the degree of water content are determined by sauce. Also, the taste derived from major sauce like a demi-glace and the basic sauce that affects cooking quality are highly recognized, but preference analyses of source and researches on each ingredients have not been performed up to now. Until today, sauces act as lubricants which add relish to dishes and aid digestion, so the importance of source is more emphasized to raise the taste, appearance, water content and specially healthy function of main ingredients. In this research, some problems of sauce itself and possibilities of improvement was grasped and then some remedies were suggested through the preference, variety and quantity analyses of demi-glace sauce practically used in hotels and restaurants around Gwang-Ju City and South Jeolla(Chon-Nam) Province. Finally, the volume of demi-glace sauce with various ingredients was suggested for various kinds of application. Through the actual proof analysis, preference of each sauce made from various kinds of ingredients was investigated. The result shows that the sauce made from beef bone is highly preferred, followed by pork bone and lamb bone. The least preferred is chicken bone.

• Korean Journal of Clinical Pharmacy
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• v.20 no.3
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• pp.183-192
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• 2010

While Self-monitoring of blood glucose (SMBG) has been recommended in some diabetes mellitus (DM) patients population according to the 2010 American Diabetes Association (ADA), 2007 Korean Diabetes Association (KDA), 2005 International Diabetes Federation guideline, it is excluded from a routine insurance coverage for outpatients in Korea. The objective of this study is to meta-analyze the impact of SMBG on HbA1c in non insulin-treated diabetes mellitus (NIT) DM patients. Published clinical literatures were identified through electronic database searches from inception and until May 2010. Studies were selected if they met the following inclusion criteria: 1) randomized controlled trials (RCTs), 2) comparing SMBG with non-SMBG in NIT type 2 diabetes, 3) measuring HbA1c as an outcome. Literature qualities were assessed by the Scottish Intercollegiate Guidelines Network Checklist. The mean difference of HbA1c between the 2 groups was pooled from non-heterogeneous 6 RCTs by meta-analysis using Review Manger (RevMan) Version 5.0 program. Pooled results demonstrated that SMBG is associated with a statistically significant improvement in glycemic control (mean HbA1c difference -0.23, 95%CI -0.32, -0.13). Sensitivity analysis showed that glycemic controls were significantly improved in patients with shorter study duration, more frequent self-monitoring, higher baseline HbA1c value, and without prior SMBG experiences. Conclusively SMBG is effective in improving glycemic control in NIT DM patients, but additional evidences from further researches in Korean patients and cost-effectiveness analysis would be necessary to make a suggestion for coverage expansion.

• Korean Journal of Construction Engineering and Management
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• v.14 no.1
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• pp.63-70
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• 2013

A judgment on the redevelopment projects' predicted profitability is an essential decision-making element for the success of the redevelopment projects. It is necessary to review the literature on profitability of redevelopment project and draw risk factors that could affect profitability through the risk analysis based on surveys. It is also necessary to judge profitability prediction toward the business value of the redevelopment project in the planning phase according to the risk analysis results which can affect the profitability prediction. In order to prevent the growing difficulties in executing the projects, a profitability prediction model is proposed using the method of management and disposal based on a proportional calculation that can estimate the share of expenses in order to judge profitability in the planning phase. With the improvement of profitability prediction models, it is possible to appropriately judge profitability in the planning phase in order to allow the prevention of suspension, reduction of project term, reduction of cost, and making of rational decisions.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.4 no.1
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• pp.8-24
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• 1979

Including the Qualfication of Staffer required for Commuinication, the National Law of Professional qualification is a basic law for supply with manpower of high growth industry, and it is aiming at perfect the national Policy Concerned improvement for education and training of staff, carrying out of state examination for qualification and getting an occupation or application for special qualification. This law has established a management committee for qualification system in The Ministry of Science and Technique ROK, and authorized competence Minister according to kind of special qualification aiming at getting employment, practical use and courteous treatment in society and economy for national qualification, and also regulated their each official duty. A qualification of staffer required for communication is an administrative measure giving as occupational certificate after some examination for knowledge, technique and faculty in vocational ability to adapt to intrinsic of telecommunication. This certificate has the cause of an attribution of over the sphere of telecommunication, and so it has been originated in international situation, and then some of them is forced by international law, otherwise it be in common use between the nations. The Characteristic and orthodox of communication certificate has been succeded continually in company with development of telecommunication and the appliable field of them is specified, but the sovereign power of nation is approved by ITU that she can extent the applicable position for communication certificate and coordinate the utility of qualification for telecommunication value. Korean telecommunication law excepted the application of communication certificate in public communication field. It is unreasonable and even disobeyed against the theory of communication science and intrinsic of telecommuncation. Therefore it should be corrected immediately and then communication certificate have to accept in the public communication field at all, if so, the application field of communication certificate can have more than useful extenxion such as administration measure should be achieved by the management committee for qualification system in Ministry of Science and Technique and competemce Minister appointed according to special kind of certificate and the administration have to manage by the method and proccess caused by communication science or cooperative system between administration, industry, education and science. And, then, every acquisitor of qualification also has to try to perfect his vocational duty sincerely and to promote each self-realization.

• Korean Chemical Engineering Research
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• v.54 no.6
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• pp.775-780
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• 2016

Recently, photovoltaic industry needs a new design of Czochralski (Cz) process for higher productivity with reasonable energy consumption as well as solar cell's efficiency. If the process uses the large size reactor for increasing productivity, it is possible to produce a 12-inch, rather than the 8-inch. Also the continuous czochralski process method can be maximized to increase productivity. In this study, it was designed to improve the yield value of ingot with optimal condition which reduce consumption of electrical power. It has increased the productivity of the 12-inch ingot process condition by using CFD simulation. I have found optimal growth rate, by comparing each growth rate the interface shape, Temperature gradient, power consumption. As a result, the optimal process parameters of the growth furnace has been derived to improve for the productivity and to reduce energy. This study will contribute to the improvement of the productivity in the solar cell industry.