• 전기학회논문지
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• 제67권3호
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• pp.374-382
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• 2018

This paper has done a hardware-based approach to increase the modulation index in 3-phase inverters, unlike the conventional software algorithm-based approaches. The minimum required time to measure the currents in a three-phase inverters with shunt resistors has also been analyzed. By the analysis, the longest time in minimum required time is AD conversion time. To shorten the minimum required time, this paper proposed a sample-and-hold(S/H) circuit implemented at the inverter current signal output to retain the current signal. When the linear operation region of an inverter with S/H was compared with that without it, the modulation index was increased by 7.8 %. Inverters with S/H circuits can employ the traditional software algorithms, such as the voltage injection method or current restoration method, and it will yield further increase the modulation index.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.165_166
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• 2009

A HTS(High Temperature Superconductor) Cable is regarded as the most underground power to respond higher power density delivery system. This paper discussed electrical characteristic and standards of HTS Cable system. Various HTS cable characteristics are examined[3-5], ad compared with XLPE cable characteristics on possible distribution system environment. HTS cable is required to stabilize thermal condition for superconducting status, possible improper operating condition which affects quench, unbalanced, and harmonics impacts are discussed. HTS cable is customer designed cable which shall be implemented in special requirement of power system, the standard origination process requires to establish a series of methodology including design manufacturing, testing and installation.

• 가정과삶의질연구
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• 제11권1호
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• pp.218-234
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• 1993

A study focused on the wives'managerial behavior and their life satisfaction according to wives'stress level ad their coping behavior. The statistical procedures used were percentile mean cronbach's a T-test F-test cluster analysis. Duncan's Multiple Range test. For the purpose the sample were conducted using questionnairs on 548 housewives that lived in seoul. The major findings wee ; 1) The wives's education level of background variables significantly was differentiated from wives' managerial behavior and their life satisfaction respectively. 2) The wives'stress level and their coping behavior respectively was higher than average. from wives'managerial behavior respectively. 4) The variable i.e. wives'stress level wives'coping behavior significantly was differentiate from wives'life satisfaction respectively In conclusion to improve wives'managerial behavior and their life satisfaction this study suggests we have to try to release or decrease wives'stress level and to do the resonable wives'co-ping behavior.

• 대한치과마취과학회지
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• 제11권2호
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• pp.146-152
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• 2011

Background: Elderly patients with progressive dementia including Alzheimer's disease (AD) are more and more often scheduled to undergo general anesthesia for various pathologies including dental problem. But, there is high risk of deterioration of underlying mental diseases and other co-morbidities. So it is important to implement preventive strategies and take adequate measures to minimize negative perioperative events in these patients. Methods: We reviewed the 17 cases of 11 patients with AD who underwent ambulatory general anesthesia for dental treatment at the clinic for the disabled in Seoul National University Dental Hospital. Results: The mean age was 68 (57-81) years. All of them were diagnosed with AD and some had hypertsnsion, bronchiectasis, urinary incontinence. For anesthesia induction, 3 cases (1 patient) was needed physical restraint, but others showed good or moderate cooperation. Drugs used for anesthesia induction was thiopental (11 cases), propofol (3 cases) and sevoflurane (3 cases). All patients received nasotracheal intubation without difficulties. Mean total anesthetic time was 3 hour 44 min ${\pm}$ 60 min and staying time at PACU was 83 ${\pm}$ 34 min. All the patients except one who showed hypertension discharged without any complication. There was no death or long term hospitalization because of severe complications. Conclusions: If general anesthesia is needed, pertinent diagnostic tests and workup about other medical problems, and appropriate anesthetic planning are essential for safety.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2009년도 춘계학술발표대회
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• pp.1186-1189
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• 2009

본 논문에서는 이동 애드 혹 네트워크의 성능 개선을 위한 방안으로 네트워크 중간에 고정 노드를 부가하여 어느 정도의 성능 향상이 있는지를 모의 실험을 통하여 평가하였다. 모의 실험 결과 이동 노드만을 사용했을 경우보다 고정노드를 함께 사용했을 때의 성능이 더 뛰어남을 알 수 있었고, 이동 노드의 이동 속도에 따른 비교에서도 고정 노드를 함께 사용한 경우가 성능이 더 뛰어남을 확인할 수 있었다. 또한 고정 노드의 개수에 따른 성능평가에서는 고정 노드를 여러 대 사용할수록 지연시간이 단축됨을 확인 할 수 있었다. 본 연구에서 제안한 방식은 이동 애드 혹 네트워크의 중간에 고정 노드를 부가하여야 하는 문제가 있으나, 비용과 처리율과의 관계를 비교한 후 비용 상승에도 불구하고 보다 높은 신뢰성과 빠른 처리율을 원하는 네트워크에 사용하면 효과적일 것이다. 향 후 본 절의 연구 결과에 이어서 애드 혹 네트워크에 몇 대의 고정 노드를 추가해야 하는지에 대한 연구가 이루어진다면 보다 높은 신뢰성을 가진 애드 혹 네트워크가 구축될 수 있을 것이다.

• 한국중재학회지:중재연구
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• 제17권2호
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• pp.101-124
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• 2007

The legal systems and open-door policies to foreign affairs in North Korea have been followed by those of China. Whereas an arbitration system of South Korea accepted most parts of UNCITRAL Model Law, North Korea has succeeded to an arbitration system of a socialist country. China, under the arbitration system of socialist country, enacted an arbitration act reflected from UNCITRAL Model Law for keeping face with international trends. We have used these three arbitration system as a tool for analyzing an arbitration system in North Korea. With an open-door policy, North Korea and China enacted an arbitration act to provide a legal security. Therefore, the core parts of arbitration system in North Korea and China are based on a socialist system while those of South Korea is on liberalism. So, North Korea and China enacted an arbitration act on the basis of institutional arbitration, on the other side, South Korea is based on ad-hoc arbitration. Because of these characters, in terms of party autonomy, it is recognized with the order as South Korea, China and North Korea. Also North Korea enacted separate 'Foreign Economic Arbitration Act' to resolve disputes arising out of foreign economies including commercial things and investments. There are differences in arbitration procedures and appointment of arbitrators : South Korea recognizes parties' autonomy, however parties should follow the arbitration rules of arbitration institutes in North Korea and China. According to an appointment of arbitrators, if parties fail to appoint co-arbitrators or chief arbitrators by a mutual agreement, the court has the right to appoint them. In case of following KCAB's rules, KCAB secretariats take a scoring system by providing a list of candidates. A party has to appoint arbitrators out of the lists provided by arbitration board(or committee) in North Korea. If a party may fail to appoint a chief arbitrator, President of International Trade Arbitration Board(or Committee) may appoint it. In China, if parties fail to appoint a co-arbitrator or a chief arbitrator by a mutual agreement, Secretary general will decide it. If a arbitral tribunal fails to give a final award by a majority decision, a chief arbitrator has the right for a final decision making. These arbitration systems in North Korea and China are one of concerns that our companies take into account in conducting arbitration procedures inside China. It is only possible for a party to enforce a final arbitral award when he applies an arbitration inside North Korea according to International Trade Arbitration Act because North Korea has not joined the New York Convention. It's doubtful that a party might be treated very fairly in arbitration procedures in North Korea because International Trade Promotion Commission controls(or exercises its rights against) International Trade Arbitration Commission(or Board).

• 천문학논총
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• 제35권3호
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• pp.29-41
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• 2020

Korea has numerous astronomical resources, such as observational records, star maps, and a wealth of literature, covering the period from the Three Kingdoms (54 BC - 932 AD) to the Joseon Dynasty (1392 - 1910 AD). The research activities related to these resources have been limited to those by individual researchers. It is now necessary to conduct research by efficiently and systematically collecting and managing Korean astronomical records using an accessible Web environment. The purpose of this study is to complete a system that enables researchers systematically to collect and verify a large number of historical records related to astronomical phenomena in a Web environment. In 2017, a preliminary survey was conducted, and the requirements pertaining to an implementation target system were devised. In addition, a joint development plan was carried out by the developer, lasting three months in 2018. Although the system is relatively simple, it is the first system to be attempted in the historical astronomy field. In order to proceed with the systematic development, the software development methodology is applied to the entire process from deriving the requirements of researchers to completing the system. The completed system is verified through integrated function and performance tests. The functional test is repeated while modifying and testing the system based on various test scenarios. The performance test uses a performance measurement test tool that takes measurements by setting up a virtual operation environment. The developed system is now in normal operation after a one-year trial period. Researchers who become authorized to use the system can use it to verify the accuracy of data and to suggest improvements. The collected feedback will be reflected in future systems, and Korean astronomical records will be available for use internationally through a multilingual service.

• 동의생리병리학회지
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• 제23권2호
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• pp.374-380
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• 2009

Samryungbaikchul-san(SRBCS) has been used in oriental medicine for the treatments of gastrointestinal and neurological disorders. Here, potential protective function of SRBCS was investigated in neural tissues in Alzheimer's disease(AD) mouse model. In primary cultured cells from the spinal cord of newborn rats, treatment of ${\beta}$-amyloid peptide elevated cell counts positive to glial fibrillary acidic protein(GFAP) or caspase 3 immunoreactivity, but the co-treatment of SRBCS reduced positive cell counts. In vivo administration of scopolamine, an inhibitor of muscarinic receptor, resulted in increases in the number of glial fibrillary acidic protein(GFAP) and caspase 3-positive cells in hippocampal subfields, which was then decreased by the treatment of SRBCS or acetylcholinesterase inhibitor galathamine. The present data suggest that SRBCS may play a protective role in damaged neural tissues caused by scopolamine treatments in mice.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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• pp.1061-1062
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• 2006

This paper represent improved On-line Turn off, commutation Angle control schemes for switched reluctance motors based on current control. For the purpose of the finding optimal commutation switching angle point, it is utilized turn on and turn off position calculation with inductance vs. current vs. flux linkage analysis method. The goal of proposed paper is the maximization of the energy conversion per stroke and maximizing efficiency and obtaining approximately flat-topped current waveform. The proposed control scheme is demonstrated on a simulation experimental result.

• Advances in environmental research
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• 제10권1호
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• pp.87-103
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• 2021

Anaerobic digestion (AD) refers to the biological process which can convert organic substrates to biogas in the absence of oxygen. The aim of this study was to determine the capability of feedstock to produce biogas and to quantify the biogas yield from different feedstocks. A co-digestion approach was carried out in a continuous stirred tank reactor operated under mesophilic conditions and at a constant organic loading rate of 0.0756 g COD/ L.day, with a hydraulic retention time of 25 days. For comparison, mono-digestion was also included in the experimental work. 2 L working volumes were used throughout the experimental work. The seed culture was obtained from composting as substrate digestion. When the feedstock was added to seeding, the biogas started to emit after three days of retention time. The highest volume of biogas was observed when the seeding volume used for 1000mL. However, the lowest volume of biogas yield was obtained from both co-digestion reactors, with a value of 340 mL. For methane yield, the highest methane production rate was 0.16 L CH4/mg. The COD with yield was at 8.6% and the lowest was at 0.5%. The highest quantity of methane was obtained from a reactor of Euphorbiaceae peel with added seeding, while the lowest methane yield came from a reactor of Euphorbiaceae stems with added seeding. In this study, sodium bicarbonate (NaHCO3) was used as a buffering solution to correct the pH in the reactor if the reactor condition was found to be in a souring or acidic condition.