• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.6
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• pp.325-332
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• 2003

The loss minimization is one of the most important problems to save the operational cost in distribution systems. This paper presents an efficient method for optimal feeder reconfiguration of distribution systems. Chaos search algorithm (CSA) is used to reconfigure distribution systems so that active power losses are globally minimized with turning on/off sectionalizing switches. In optimization problem, the CSA searches the global optimal solution on the basis of regularity in chaotic motions and easily escapes from local or near optimal solution. The CSA is tested on 15 buses and 32 buses distribution systems, and the results indicate that it is able to determine appropriate switching options for global optimum reconfiguration.

• Proceedings of the Korean Society of Computer Information Conference
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• 2017.07a
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• pp.105-106
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• 2017

최근 고품질 방송콘텐츠 보호에 대한 요구가 증가하면서 DVB, MPEG, ATSC 등 국제표준단체에서는 보안 성능이 우수한 디지털방송 보호규격으로써 DVB-CSA ver.3에 대한 논의가 본격화되었다. 본 논문에서는 디지털방송에서 보안성능이 우수한 것으로 알려진 방송콘텐츠 암호화 규격인 DVB-CSA ver. 3 표준규격을 기반으로한 방송콘텐츠 스크램블링 시스템 설계에 대해 소개한다.

• Archives of Reconstructive Microsurgery
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• v.2 no.1
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• pp.82-92
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• 1993

A comparative study was undertaken to evaluate the contact Neo-dymium : yttrium aluminum garnet(Nd:YAG) laser system for vascular anastomosis of small caliber blood vessels(diameter 0.5-1.2 mm) in the animal model. In this study 40 femoral arteries and 40 femoral veins of Sprague-Dawley rats were anastomosed by contact laser assisted microvascular anastomosis(LAMA) utilizing 3 stay sutures which were placed 120 degrees apart and the intervals welded with contact Nd:YAG laser unit, conventionally sutured anastomosis(CSA) served as controls. The time needed for vascular anastomosis, patency rate(immediate postoperative, postoperative 2nd day, postoperative 1 week, postoperative 4 weeks), gross and microscopic evaluations were compared to conventional microsurgical suture technique. The results are as follows: 1. Postoperative patency rate was 82.5% for femoral artery and 75% for femoral vein by contact LAMA technique compared to 90% and 75% by CSA technique at postoperative 4 weeks. 2. Less time-consumed for arterial anastomosis by 6 minutes 23 seconds and venous anastomosis by 8 minutes 55 seconds with contact LAMA technique compared to CSA technique. 3. Grossly almost complete healing had taken place by postoperative 1 week by contact LAMA technique. 4. Aneurysm formation was 5% for femoral artery and 15% for femoral vein by contact LAMA technique compared to 5% and 10% respectively by CSA technique. 5. Microscopically, re-endothelization was complete by postoperative 7th day by contact LAMA technique. There was less medial hypertrophy and hyperplasia and also less inflammatory response compared to CSA.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.378-388
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• 2016

International societies are currently working together to achieve the Climate-Smart Agriculture (CSA) initiative which aims the triple wins: (1) sustainably increasing agricultural productivity and incomes; (2) adapting and building resilience to climate change; and (3) mitigating greenhouse gases emissions. In terms of its scope and context, CSA follows the '3Nong (三農)' vision cast about 200 years ago by Dasan Jeong Yak-Yong who emphasized the triad of governance, management and monitoring towards comfortable, profitable and noble agriculture. Yet, the CSA provides the practical aims that facilitate the development of holistic indicators for quantitative evaluation and monitoring, on which decision-making support system is based. In this study, we introduce an agent-based model, i.e. Mathematical Programming Multi-Agent Systems (MP-MAS), as a tool for supporting the decision-making toward CSA. We have established the initial version of MP-MAS adapted for domestic use and present the preliminary results from an application to the rice farming case in Haenam, Korea. MP-MAS can support both farmers and policy-makers to consider diverse management options from multiple perspectives. When the modules for system resilience and carbon footprint are added, MP-MAS will serve as a robust tool that fulfills not only CSA but also Dasan's '3Nong' vision of sustainable agricultural-societal systems.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.4
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• pp.235-250
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• 2021

The overarching question of this study is how a typical rice cultivation system in Gimje, Korea was keeping up with the triple-win challenge of climate-smart agriculture (CSA). To answer this question, we have employed (1) quantitative data from direct measurement of energy, water, carbon and information flows in and out of a rice cultivation system and (2) appropriate metrics to assess production, efficiency, GHG fluxes, and resilience. The study site was one of the Korean Network of Flux measurement (KoFlux) sites (i.e., GRK) located at Gimje, Korea, managed by National Academy of Agricultural Science, Rural Development Administration. Fluxes of energy, water, carbon dioxide (CO₂) and methane (CH₄) were directly measured using eddy-covariance technique during the growing seasons of 2011, 2012 and 2014. The production indicators include gross primary productivity (GPP), grain yield, light use efficiency (LUE), water use efficiency (WUE), and carbon uptake efficiency (CUE). The GHG mitigation was assessed with indicators such as fluxes of carbon dioxide (F_CO2), methane (F_CH4), and nitrous oxide (F_N2O). Resilience was assessed in terms of self-organization (S), using information-theoretic approach. Overall, the results demonstrated that the rice cultivation system at GRK was climate-smart in 2011 in a relative sense but failed to maintain in the following years. Resilience was high and changed little for three year. However, the apparent competing goals or trade-offs between productivity and GHG mitigation were found within individual years as well as between the years, causing difficulties in achieving the triple-win scenario. The pursuit of CSA requires for stakeholders to prioritize their goals (i.e., governance) and to practice opportune interventions (i.e., management) based on the feedback from real-time assessment of the CSA indicators (i.e., monitoring) - i.e., a purpose-driven visioneering.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.16 no.4
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• pp.33-41
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• 2006

RSA cryptosystem is of great use in systems such as IC card, mobile system, WPKI, electronic cash, SET, SSL and so on. RSA is performed through modular exponentiation. It is well known that the Montgomery multiplier is efficient in general. The critical path delay of the Montgomery multiplier depends on an addition of three operands, the problem that is taken over carry-propagation makes big influence at an efficiency of Montgomery Multiplier. Recently, the use of the Carry Save Adder(CSA) which has no carry propagation has worked McIvor et al. proposed a couple of Montgomery multiplication for an ideal exponentiation, the one and the other are made of 3 steps and 2 steps of CSA respectively. The latter one is more efficient than the first one in terms of the time complexity. In this paper, for faster operation than the latter one we use binary signed-digit(SD) number system which has no carry-propagation. We propose a new redundant binary adder(RBA) that performs the addition between two binary SD numbers and apply to Montgomery multiplier. Instead of the binary SD addition rule using in existing RBAs, we propose a new addition rule. And, we construct and simulate to the proposed adder using gates provided from SAMSUNG STD130 $0.18{\mu}m$ 1.8V CMOS Standard Cell Library. The result is faster by a minimum 12.46% in terms of the time complexity than McIvor's 2 method and existing RBAs.

• Journal of the Korea Safety Management & Science
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• v.7 no.5
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• pp.135-153
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• 2005

자가통제평가(CSA : Control Self Assessment)는 핵심사업 목적을 달성하는데 개입되는 위험 그리고 그러한 사업위험을 관리하기 위하여 설계된 내부통제를 공식적이고 문서화된 협력적 프로세스에 의하여 검토하기 위하여 사용되는 방법론이다. 현재 많은 기업에서 효과적인 조직통제와 비즈니스 프로세스 개선을 위하여 전문 감사인과 경영인들이 기업지배구조 조직의 강력한 위험관리 도구로서 자가통제평가의 필요성을 강조하고 있다. 자가통제평가는 해당 조직의 담당부서나 팀에서 내부통제평가를 통하여 내부통제상의 재무보고, 준법, 사업 및 운영상의 효율성 등을 확보하기 위해서 설치되며, 효과적인 모니터 장치로서 기업지배구조상의 업무 프로세스를 정비하고 업무에서 발생하는 제반 정보의 흐름을 원활하게 해서 조직에게 손해가 발생할 수 있는 여러 가지 위험으로부터 회사를 사전에 차단하는 기능을 한다. 이러한 부분에서 효과적인 자가통제평가 시스템을 구축하는 것이 중요할 것이다. 본 연구에서는 e-Business 관련 기업지배구조의 안전성을 확보하기 위한 자가통제평가 모델에 대한 개발 필요성과 관련 자가통제평가 세가지 기본 모델들을 통하여 장단점을 제시하고, 자가통제평가 모델의 필요성을 논의하였다.

• The KIPS Transactions:PartA
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• v.10A no.6
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• pp.671-676
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• 2003

In this paper, we proposed a new First Partial product Addition (FPA) architecture with new compressor (or parallel counter) to CSA tree built in the process of adding partial product for improving speed in the fast parallel multiplier to improve the speed of calculating partial product by about 20% compared with existing parallel counter using full Adder. The new circuit reduces the CLA bit finding final sum by N/2 using the novel FPA architecture. A 5.14nS of multiplication speed of the $16{\times}16$ multiplier is obtained using $0.25\mu\textrm{m}$ CMOS technology. The architecture of the multiplier is easily opted for pipeline design and demonstrates high speed performance.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.6
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• pp.516-521
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• 2005

Drug delivery to the lymphatic system may be important in terms of the treatment with lymphatic involvement, such as tumor metastases and immunization. Especially, drug transport via the intestinal lymphatics after oral administration has been attracted lots of interests. The purpose of this study was to prepare cyclosporin A (CSA)-loaded liposomes, with different characteristics, and evaluate their mucoadhesivity. Three liposome preparations were formulated: cationic stearylamine liposomes (SA-Lip), anionic phosphatidylserine liposomes (PS-Lip), Polymer (chitosan)-coated liposomes (CS-Lip), and characterized. The liposome preparations were found to be spherical in shape, with PS-Lip being the smallest. The liposome preparations exhibited entrapment efficiencies in the order: PS-Lip $(52.5{\pm}2.9%)$ > SA-Lip $(48.8{\pm}3.3%)$ > CS-Lip $(41.7{\pm}4.2%)$. Finally, mucoadhesive tests were carried out using rat intestine, with SA-Lip (67%) showing the best adhesive rate of the three preparations (PS-Lip: 56%, CS-Lip: 61%). These results suggest that a positive charge on the surface of drug carriers may be an important factor for the intestinal drug delivery.

• Nuclear Engineering and Technology
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• v.56 no.1
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• pp.189-194
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• 2024

This paper presents a radiation-hardened-by-design preamplifier that utilizes a self-compensation technique with a charge-sensitive amplifier (CSA) and replica for total ionizing dose (TID) effects. The CSA consists of an operational amplifier (OPAMP) with a 6-bit binary weighted current source (BWCS) and feedback network. The replica circuit is utilized to compensate for the TID effects of the CSA. Two comparators can detect the operating point of the replica OPAMP and generate appropriate signals to control the switches of the BWCS. The proposed preamplifier was fabricated using a general-purpose complementary metal-oxide-silicon field effect transistor 0.18 ㎛ process and verified through a test up to 230 kGy (SiO₂) at a rate of 10.46 kGy (SiO₂)/h. The code of the BWCS control circuit varied with the total radiation dose. During the verification test, the initial value of the digital code was 39, and a final value of 30 was observed. Furthermore, the preamplifier output exhibited a maximum variation error of 2.39%, while the maximum rise-time error was 1.96%. A minimum signal-to-noise ratio of 49.64 dB was measured.