• 전력전자학회:학술대회논문집
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• 전력전자학회 2014년도 전력전자학술대회 논문집
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• pp.120-121
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• 2014

장거리 이송이 가능한 선형동기 전동기 구조를 제안하고, 수학적 모델링을 하였으며, PI제어기를 포함하는 제어알고리즘을 제안하여, 실험으로 그 결과를 확인하였다. 추진제어기의 출력은 Park's, Clake's Transformation을 이용하여 코일을 구동하는 전류 명령을 발생시켰으며 개별 코일을 독립적으로 구동하는 아날로그 전류제어기를 OP-Amp로 구현하였다. 실험결과는 속도 오차는 4 ~ 10% 이하의 결과를 얻었다.

• The Korean Journal of Physiology and Pharmacology
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• 제3권5호
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• pp.481-490
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• 1999

To investigate the changes in the responses of vestibular neurons with time during vestibular compensation, the resting activity and dynamic responses of type I and II neurons in the medial vestibular nuclei to sinusoidal angular acceleration were recorded following unilateral labyrinthectomy (ULX) in Sprague-Dawley rats. The unitary extracellular neuronal activity was recorded from the bilateral medial vestibular nuclei with stainless steel microelectrodes of $3{\sim}5\;M{\Omega}$ before ULX, and 6, 24, 48, 72 hours, and 1 week after ULX under pentobarbital sodium anesthesia (30 mg/kg, i.p.). Gain (spikes/s/deg/s) and phase (in degrees) were determined from the neuronal activity induced by sinusoidal head rotation with 0.05, 0.1, 0.2, and 0.4 Hz. The mean resting activity before ULX was $16.7{\pm}8.6$ spikes/s in type I neurons $(n=67,\;M{\pm}SD)$ and $14.5{\pm}8.4$ spikes/s in type II neurons (n=43). The activities of ipsilateral type I and contralateral type II neurons to the lesion side decreased markedly till 24 hr post-op, and a significant difference between ipsilateral and contralateral type I neurons sustained till 24 hr post-op. The gain at 4 different frequencies of sinusoidal rotation was depressed in all neurons till 6 or 24 hr post-op and then increased with time. The rate of decrease in gain was more prominent in ipsilateral type I and contralateral type II neurons immediately after ULX. Although the gain of those neurons increased gradually after 24 hours, it remained below normal levels. The phase was significantly advanced in all neurons following ULX. These results suggest that a depression of activities in ipsilateral type I and contralateral type II neurons is closely related with the occurrence of vestibular symptoms and restoration of activities in those neurons ameliorates the vestibular symptoms.

• 실천공학교육논문지
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• 제15권1호
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• pp.107-117
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• 2023

지난 2021년 7월 6일 개정된 현장실습학기제 운영규정은 표준화된 현장실습학기제 운영을 통해 현장실습의 질적 내실화 및 학생 권익의 증진을 모색하고 있다. 하지만, 개정 내용 중 최저임금의 75%에 달하는 실습지원비와 최대 25%에 달하는 직무교육 비율은 현장실습학기제로의 기업참여에 큰 어려움으로 작용하고 있다. 이에 본 연구는 현장실습학기제의 개념과 교육부 고시 개정의 주요 내용을 검토하고, 이에 대한 기업의 인식 및 대응 현황을 살펴보고자 하였다. 연구 결과, 일부 기업들은 고시 개정 자체에 대해 충분히 인지하고 있지 못하는 것으로 나타났다. 뿐만 아니라, 실습지원비 관련 고시 개정이 기업 현장의 큰 고민인 것으로 나타났으며, 직무교육에 대한 부담 또한 존재하는 것으로 나타났다. 이러한 연구결과를 토대로 결론에서는 정책적 개선 방향에 대해 논의하였으며, 본 연구의 시사점과 한계점을 제시하였다.

• 한국자동차공학회논문집
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• 제13권3호
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• pp.178-185
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• 2005

Crack tip displacement is originated by tensile stress component, s and shear stress component, t on pure Mode I and pure Mode II. The crack tip displacement(CTD) depends on combined types of different two stress components under mixed-mode loading conditions (MMLC). Thus, the analysis of crack tip displacement must be CTD vector, dv which is composition of ds and dt under MMLC. In this paper, various effects of MMLC on the crack closure are studied experimentally. The crack closure magnitude is calculated from the information of crack tip displacement under MMLC. This information has been obtained from the high resolution optical microscope in direct observations of crack displacement behavior at the crack tip. Observed crack tip displacement is analyzed by using CTD vector to determine crack opening load. The various effects of MMLC on the crack closure are explained using crack opening ratio with crack length and mode mixture. The effective stress intensity factor considering crack closure is also discussed.

• Architectural research
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• 제9권2호
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• pp.1-9
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• 2007

As aging is notably developed, the elderly find it challenging to get around in housing chosen in their midlife, and seek for an alternative residential setting enabling them to continue the independent living. This research focuses on the residential mobility of the elderly who have recently moved to senior housing, and also is to investigate their residential satisfaction at previous residence. As a cross-sectional study, the research adopts the self-administered questionnaire survey. The questionnaires are mailed out, and one out of the two responses is retrieved. To investigate the residential mobility of the elderly, the research model is constructed based upon Morris and Winter's Housing Adjustment Theory. The result shows that the residential mobility of elderly from previous residence is a need-based choice, want-driven behavior and demand-oriented decision to maintain continued independence and utilize resources available during the aging process. Also, it is found that the vast majority of both co-op and rental households are satisfied with their previous residential environment. The previous residential satisfaction of co-op elderly is significantly influenced by household and housing characteristics, housing norm status, and environmental needs for independent living while only housing norm status is a significant predictor to explain the previous residential satisfaction of rental elderly.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 심포지엄 논문집 정보 및 제어부문
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• pp.288-290
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• 2006

An efficiency improving method for Uninterruptible Power Supply System(UPS) was developed by using OP-AMP based application circuits such as voltage detection device, current detection device and static switch control device. The efficiency improving algorithm was made by mixing the operating concepts of On-Line type UPS with the operating concepts of Off-Line type UPS. The UPS' inverter does not work if the UPS' output load current is not higher than the low load operating current which is about 0-30(%) of the UPS' output load capacity. The low load operating current is adjustable within the half of the UPS' output load capacity. If the UPS' output load current is rising over than the low load operating current, the UPS' inverter starts working and the inverter output power feeds to the loads of UPS. If UPS' input power breaks out while UPS' inverter does not operate because the load current is low, the inverter starts working within 4(ms) with excessive output voltage which is ${\pm}$8(%) of normal UPS' output voltage. Like these. UPS can continuously feeds power to it's load device and reduce power consumptions.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2005년도 춘계학술발표대회
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• pp.663-666
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• 2005

은행, 저축은행, 신용정보회사 등 금융기관에서는 채권관리 및 회수, 각종 우편물 발송 등의 업무처리를 위해 채무자 또는 고객의 최종 주소의 파악이 필요하다. 주소 파악을 위한 업무프로세스는 금융기관 직원이 채무자와 사실 관계를 증명하는 서류를 작성하고, 행정기관에 직접 방문하여 민원서류를 발급 받는 등 Off-line으로 이루어지고 있다. 이러한 민원서류 발급 업무량은 경제상황의 악화와 그에 따른 신용불량자의 대거 발생 등으로 인해 지속적으로 증대되고 있다. 따라서 행정전산망과 금융전산망을 서로 연결하여 신속하게 정보를 파악할 수 있도록 하는 주소 인증공동이용시스템(ACCESS, Address Certification Co-opErating SyStem)을 구축하는 것이 필요한 실정이다. 이에 본 연구에서는 ACCESS를 구축을 위한 설계를 통하여, 행정기관 민원서류 발급업무 담당자, 금융기관 해당업무 종사자 등의 업무를 대폭 줄임으로서 산업생산성을 제고 하는 방안을 제시하고자 한다. 또한 향후 행정전산망과 금융전산망의 연결체계에서 새롭게 구축될 다양한 정보서비스의 유형을 처리 할 수 있는 기반을 마련하여, 효율적인 정보의 공유와 유통 및 이를 통한 시너지효과를 창출하고, 정보자원의 활용 및 가치를 극대화하고자 한다.

• Journal of information and communication convergence engineering
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• 제20권3호
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• pp.143-152
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• 2022

The ongoing adoption of 5G will increase the data traffic, throughput, multimedia services, and power consumption for future wireless applications and services, including sensor and mobile networks. Multipath fading on wireless channels also reduces the system performance and increases energy consumption. To address these issues, device-to-device (D2D) and cooperative communications have been proposed. In this study, we propose two inter-clustering models using the relay selection method to improve system performance and increase energy efficiency in cooperative D2D networks. We develop two inter-clustering models and present their respective algorithms. Subsequently, we run a computer simulation to evaluate each model's outage probability (OP) performance, throughput, and energy efficiency. The simulation results show that inter-clustering model II has the lowest OP, highest throughput, and highest energy efficiency compared with inter-clustering model I and the conventional inter-clustering-based multirelay method. These results demonstrate that inter-clustering model II is well-suited for use in 5G overlay D2D and cellular communications.

• 치위생과학회지
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• 제19권3호
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• pp.162-169
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• 2019

Background: Oral diseases are caused by various systemic and local factors, the most closely related being the biofilm. However, the challenges involved in removing an established biofilm necessitate professional care for its removal. This study aimed to evaluate and compare the effects of professional self and professional biofilm care in healthy patients to prevent the development of periodontal diseases. Methods: Thirty-seven patients who visited the dental clinic between September 2018 and February 2019 were included in this study. Self-biofilm care was performed by routine tooth brushing and professional biofilm care was provided using the toothpick method (TPM) or the oral prophylaxis (OP) method using a rubber cup. Subgingival bacterial motility and halitosis (levels of hydrogen sulfide, $H_2S$; methyl mercaptan, $CH_3SH$; and di-methyl sulfide, $(CH_3)_2S$) were measured before, immediately after, and 5 hours after the preventive treatment in the three groups. Repeated measures analysis of variance test was performed to determine significant differences among the groups. Results: TPM was effective immediately after the prevention treatment, whereas OP was more effective after 5 hours (proximal surfaces, F=16.353, p<0.001; smooth surfaces, F=66.575, p<0.001). The three components responsible for halitosis were effectively reduced by professional biofilm care immediately after the preventive treatment; however, self-biofilm care was more effective after 5 hours ($H_2S$, F=3.564, p=0.011; $CH_3SH$, F=6.657, p<0.001; $(CH_3)_2S$, F=21.135, p<0.001). Conclusion: To prevent oral diseases, it is critical to monitor the biofilm. The dental hygienist should check the oral hygiene status and the ability of the patient to administer oral care. Professional biofilm care should be provided by assessing and treating each surface of the tooth. We hope to strengthen our professional in biofilm care through continuous clinical research.

• 한국융합학회논문지
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• 제10권12호
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• pp.71-80
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• 2019

DevOps는 소프트웨어 개발과 운영의 합성어로 소프트웨어 생명주기 동안 사용되는 다양한 환경과 도구들이 존재한다. DevOps는 서비스를 제공함에 있어 빠르고 안전한 전개가 핵심이다. 이를 위해 Java, C/C++, Python, PHP, Ruby, Node.js, goLang 의 7가지 개발 언어와 전자정부프레임워크, Spring, Struts, DJango, Laravel, Rails, Express의 7가지 프레임워크 서비스를 사전에 제공하는 웹 기반의 통합 IDE를 제안한다. 통합 IDE는 플랫폼 내에서 웹 기반의 에디터를 통해 직접 개발이 가능하며, 리눅스 컨테이너를 이용하여 원 클릭으로 운영환경 이관이 가능하도록 구현하였다. 제안한 플랫폼은 개발 소스에 대해 컴파일 시간, 배포 시간, 배포된 앱의 처리량에 대한 성능 평가가 이루어졌으며, 상용 수준의 클라우드 서비스를 제공할 수 있는 성능을 보여준다.