• 한국콘텐츠학회논문지
• /
• 제10권9호
• /
• pp.107-116
• /
• 2010

시설물 입지 선정 문제(FLP)는 전통적인 최적화 문제중에 하나이다. FLP에 공급제약과 하나의 고객은 하나의 시설물에서만 제품을 공급받을 수 있다는 제약을 추가하면 단일 시설물 공급제약을 가지는 시설물 위치 설정 문제(SSFLP)가 된다. SSFLP는 NP-hard 문제로 알려져 있으며 진화 알고리즘과 같은 휴리스틱 알고리즘을 사용하여 해결하는 것이 일반적이다. 본 논문에서는 SSFLP를 위한 효율적인 진화 알고리즘을 제안한다. 제안하는 알고리즘은 적응형 링크 조절 진화 알고리즘과 3가지 휴리스틱 해 개선 방법을 조합하여 고안되었다. 제안하는 알고리즘을 벤치마크 문제에 적용하여 다른 알고리즘과 성능을 비교분석해 본 결과, 제안하는 알고리즘은 중간 크기의 문제에서 대부분 최적해를 찾았으며 큰 문제에서도 안정된 결과를 보여주었다.

• 한국주거학회논문집
• /
• 제18권1호
• /
• pp.19-26
• /
• 2007

The purpose of this study was to fine the changes in lavatory/bathroom and daily lives to clarify the modernization process of the housing through everyday affairs and adjustment behaviors after the period of opening the port with microscopic perspectives. For the purpose, reviews were focused on hygiene and cleanliness in lavatory/bathroom and the changes in such areas. Secondly, how the process of conflict and settlement due to such changes had been approached since modernization was studied. Research method used were literature review and field study. The results of the study were as the follows: From the perspective of 'hygiene' and 'cleanliness', which were the main characteristics of modernization, the lavatory/bathroom culture in traditional Korean housing might be considered very unsanitary and despicable. The actual problems encountered by the inhabitants, however, might be less significant than those discovered by the pioneers at that time. Despite such reality, housing adjustments through renovations of the bathrooms and lavatories by some classes implied the need for housing, which had been inhibited in themselves. Also it was found that the family conflicts due to cultural and life style differences existed in each time period.

• 제어로봇시스템학회논문지
• /
• 제15권12호
• /
• pp.1175-1183
• /
• 2009

In photovoltaic(PV) generator systems, DC-DC converters are significantly considered for control system performance in power quality point of view. This paper presents a novel adaptive control method for DC-DC converters applied in PV generator systems. First, we derive a state-space average model of the converter system and then propose a reset control methodology to enhance transient response performance for time-varying PV systems. For estimating parameters of a reset control, a gradient descent optimization is utilized and an adjustment rule of them are derived respectively. An objective of the optimization is that characteristic equation of an augmented system model which is formed with an converter system model and an reset control is to trace a predefined polynomial given as a reference characteristic model. Next, we accomplish stability analysis by means of a well-known Lyapunov theory for nonlinear converter systems including time-varying voltage excitation from a PV generator. Numerical simulation demonstrates reliability of our control methodology and its superiority by comparison to a traditional control strategy.

• 한국정보기술학회 영문논문지
• /
• 제10권2호
• /
• pp.49-59
• /
• 2020

As technologies have been developing, our lives are getting easier. Today we are surrounded by the new technologies such as AI and IoT. Moreover, the word, "smart" is a very broad one because we are trying to change our daily environment into smart one by using those technologies. For example, the traditional workplaces have changed into smart offices. Since the 3rd industrial revolution, we have used the touch interface to operate the machines. In the 4th industrial revolution, however, we are trying adding the speech recognition module to the machines to operate them by giving voice commands. Today many of the things are communicated with human by voice commands. Many of them are called AI things and they do tasks which users request and do tasks more than what users request. In the 4th industrial revolution, we use smartphones all the time every day from the morning to the night. For this reason, the privacy using phone is not guaranteed sometimes. For example, the caller's voice can be heard through the phone speaker when accepting a call. So, it is needed to protect privacy on smartphone and it should work automatically according to the user context. In this aspect, this paper proposes a method to adjust the voice volume for call to protect privacy on smartphone according to the user context.

• 한국산업정보학회논문지
• /
• 제28권4호
• /
• pp.21-34
• /
• 2023

연합학습은 동기식 연합학습과 비동기식 연합학습으로 구분된다. 그 중에서 비동기식 연합학습은 동기식 연합학습 보다 시간적인 이득이 있으나 좋은 모델 성능을 얻기 위한 도전 과제가 남아있다. 특히 non-IID 학습 데이터셋에서 성능열화 방지, 적절한 클라이언트 선택 및 오래된 그래디언트 정보 관리는 모델 성능 개선에 있어 중요하다. 본 논문에서는 K-비동기식 연합학습을 다루고 있으며 non-IID 데이터셋을 통해 학습한다. 또한 기존 방식이 선택할 클라이언트 수에 있어서 정적인 K개를 사용한 것과 달리 동적으로 K 값을 조절하는 알고리즘을 제안하여 학습 시간을 줄일 수 있었다. 추가적으로, 오래된 그래디언트를 다루는 방식을 활용해 모델 성능 개선을 이루었음을 보여준다. 마지막으로 강한 모델 안정성을 얻기 위해 모델 성능을 평가하는 방식을 활용하였다. 실험 결과를 통해 전체 알고리즘을 활용했을 때 학습 시간 단축, 모델 정확도 향상, 모델 안정성 향상의 이득을 얻을 수 있음을 보여준다.

• Journal of Ginseng Research
• /
• 제20권4호
• /
• pp.472-500
• /
• 1996

Researches on mineral nutrition, physiology and phyrsiological diseases, . cultivaction methods. brceding. pest control quality management and extension during 1976-1995 in Korea were reviewed Review in brceding and pest control was restricted to the researches directely related to cultivaction. Mineral nulrient up take. partion and varicos factors such as top dreasing. Light intersity etc. and interrelationship between minerals were investigated. Top dressing was not effective due to low minera1 requorement Physiological characteristics on tempelature light and water were well elucidated and applied to assess traditional cultivation method and its inovation. Photosyrnthetic pigments. light harvest proteins and activity of related enzymes were studied. In nitrogen metabolism arginine, praline, ammonium, threonine appeared to have important role in re growth of shoot Saponin metabolism was studied in relation to growth and new ginsenosides were found but physiological role of saponin was not clearly elucidated yet Endogenous growth regulators were reported and various erogenous growth regulators were studied for growth stimulation. short stem and seed pruning etc. Various physiological diseases were investigated for cause and control measures were established. Water culture was little studied Forest culture was studied but not retched the recommendable stage Drip irrigation straw mulching. seasonal shading and soil preparation method including soil fertility adjustment were established for practical application. Shading materials completely changed to polyethylene net and materials of polymers The research on ginseng cultivation in paddy field opened the way to establish the permanent ginseng cultivation plantation Ginseng harvester and seeder were developed in the late 1950s. Transplanted and many other machines were developed in the early 1990s. In ginseng breeding only pure line selection was of practical significance several verities were at the stage of seed propagation at ginseng plantations. Mutation breeding (${\gamma}$-ray. X-ray chemicals) was not successful. The research on plantlet formation through tissue culture was a little progressed but still far behind to vegetative propagation. Disease control research was concentrated in the isolation and identification of pathogans. their ecological charactelistics and biological control and soil humigation. Potato root rot nematodes was found and control method was established. Insect and small animal control research was greatly progresses in identification, ecological investigation, and ecological and physical control. Weed control was less important due to the development of mulching method of ridge and ditch. Quality factors of raw ginseng in relation to red ginseng process were extensively studied. Traditional quality measures were elucidated in accordance with modern analytical chemistry resulting in the importance of peptides in the centrat part rather than ginsenosides For large root production growth promoting rootzone micrcorganisms (PGPRM) were isolated and active compounds were identified. Field test on PGPRM was on going. Varictus methods formality improvement through cultivation were developed. Management research of ginseng production was rare Extension was active throuch official and private organizations and through workshop for the extension specialists, and direct lectures to grower's. Extension services made the researcher to understand the existing problems at grower's fields. Research environment for ginseng production was in prime time only for three years when Korea Ginseng Research Institute was established then gradually aggravated.

• 한국컴퓨터정보학회논문지
• /
• 제11권3호
• /
• pp.117-124
• /
• 2006

본 논문에서는 자율적인 작업 처리 능력을 가진 이동 에이전트의 효율적인 이주를 위해 네트워크 트래픽 감지를 이용한 최적의 이주 노드 경로 탐색 및 최적 노드로의 경로조정 기법과 노드 재지정 기법을 제시한다. 기존의 이동 에이전트는 사용자로부터 다양한 작업을 부여받거나 혹은 에이전트의 작업 처리 결과 량이 매우 많을 경우, 에이전트의 크기 증가로 인해 네트워크 과부하 및 트래픽을 가중시킬 수 있다. 또한, 많은 네트워크 트래픽이 발생한 시점에서 사용자가 지정한 라우팅 스케줄(Routing Schedule)에 따라 이주를 수행하면 많은 노드 순회 시간 비용이 소요됨은 물론 통신망 결손 및 노드 장애와 같은 특정한 상황에 능동적으로 대처할 수 없다. 따라서 본 논문에서는 많은 네트워크 트래픽 발생 경로나 시점에서의 에이전트 이주 시 사용자에 의한 수동적 라우팅 스케줄 지정 방식에서 탈피하여 네트워크 트래픽 감지를 이용한 목적노드까지의 최적 경로 탐색을 통해 자동적인 경로 조정을 수행하는 에이전트의 이주 기법을 제시한다. 최적 이주 경로 탐색 및 조정 기법은 네트워크 트래픽 경로를 회피하는 방식으로 이동 에이전트의 순회 작업 처리 시간을 단축시키고 분산 노드에 대한 이주 신뢰성을 보장해준다.

• 자원ㆍ환경경제연구
• /
• 제13권4호
• /
• pp.735-761
• /
• 2004

해외자원개발사업은 성공할 경우 높은 수익률을 보장하지만 장기적인 투자기간과 높은 시장위험부담으로 인하여 사업의 가치분석에 있어서 사업기간 동안의 여러 가지 변수들을 분석할 수 있는 유연성을 요구하고 있다. 기업의 투자 의사결정과정에서 가장 널리 이용되는 평가방법인 전통적 기존의 현금흐름할인법의 단점을 보완할 대안으로서 제시된 옵션가격 결정모형(Option Pricing Model)을 여타의 다른 자산의 평가 및 사업성 평가에 응용하고자 하는 연구 분야인 실물옵션(Real Options)은 특히 위험도가 큰 자원개발사업의 가치를 평가할 좋은 방법론으로 주목받아왔으나, 다양한 현실적 상황을 도입하게 되면 확률과정이 난해한 형태로 변하여 수학적 처리가 용이하지 않아 실용화에 가장 큰 걸림돌로 작용하고 있다. 따라서 기존의 연구들은 확률과정의 선정과정에서 자원개발사업의 특성이나 실용성을 고려하여 확률과정을 선정하지 않고 기초적인 확률과정을 적용하여 왔다. 본 연구에서는 해외자원개발사업을 대상으로 옵션가격 결정모형을 활용하는 경우를 산정하여, 해외자원개발사업의 평가에 쉽게 활용될 수 있는 단순화된 함수의 형태로 표현된 옵션가격 결정모형을 제시해 보았다. 즉, 이론적인 정교한 확률과정을 도출하기보다는 자원개발사업의 특징을 충분히 반영하면서도 사업평가실무에 손쉽게 이용될 수 있는 현실적이면서도 단순한 확률과정을 선정하고자 하였다. 이를 위하여 구리, 연, 아연의 국제시장가격의 특성과 연-아연광 개발사업의 사례를 활용하여 기존의 모형연구들과 달리 실제의 위험을 모두 분석하되, 분석하는 모형을 최대한 단순화하여가는 과정을 통하여 Gibson-Schwartz가 제안한 Two-Factor Model과 Long-Term Asset Model을 적절한 모형으로 선정하고, 이를 바탕으로 운영옵션과 투자개시옵션의 두 가지 경영옵션을 분석하여 그 결과를 제시하였다. 본 연구에서 분석, 제안한 단순화 과정은 앞으로 옵션가격 결정이론을 바탕으로 한 가치평가모형의 실제사례 적용연구에서 활용될 수 있을 것으로 기대한다.

• 한국철도학회논문집
• /
• 제18권2호
• /
• pp.166-174
• /
• 2015

직접수요모형은 전통적 4단계 수요예측방법론보다 적은 비용과 시간으로 기본구상단계에 적합한 분석방법이다. 본 연구에서는 기존 읍면동 기준보다 약 1/24 공간적 크기를 가진 소지역(집계구)단위 사회경제지표를 활용하여 지방 광역권 12개 도시철도 노선을 대상으로 직접수요모형을 구축하여 예측수요를 실적자료와 비교 분석하였다. 하지만 통계적 분석에 의존하는 직접수요모형은 역별 특성을 반영하지 못하여 승차인원 예측에 한계가 있으며 본 연구에서는 승차인원에 영향을 미치는 인자를 찾아내고 각 영향인자들의 표준화 및 기준을 제시하였다. 특히 사회적 이슈가 되고 있는 경전철 노선 54개 역을 대상으로 실증분석하여 역 특성 기초자료 수집, 분석, 보정방안에 대해 논의하였다. 경전철 역을 대상으로 제안된 방안의 적용성을 검토하였고 향후 직접수요모형의 활용성을 높일 수 있을 것으로 기대된다.

• 대한가정학회지
• /
• 제28권4호
• /
• pp.65-86
• /
• 1990

Living conditions of the rural elderly were assessed in terms of clothing behavior, health and nutritional status, housing and envioronmental condition, and psychological adjustment. The subjects were eighty individuals over sixty residing in the rural community of Iksan-kun, Chollabukdo. The interview method using questionnaires, direct measurement, and observation was used for this study. Data were compared with those obtained from a previous study of the elderly residing in an urban area. Clothing behavior showed that the elderly residing in the rural community were more concerned about plain and conservative design of clothes than their urban counterparts. Special protective clothes for cropdusting with agricultural chemicals had not been prepared. The following urgent needs were pointed out: development and supply of agricultural chemical protective clothing and development and education of appropriate washing and clothing care methods. The health status of the elderly was generally good, but poor eating habits were found more frequently in the rural elderly than among the urban dwellers. Several dietary nutrient intakes were insufficient. Contrasting the urban elderly with the rural group, it was found that the urban group lacked sufficient vitamin A and vitamin C and the urban women had insufficient calorie whereas the rural group was deficient in protein, vitamin A, calorie, and fat. A significant relationship was found between dietary nutrient intake and health index, food habit points, self recognized health status, meal satisfaction, and economic status. Urgent needs of the development of a nutrition education program for the elderly were pointed out. Most of elderly residing in the surveyed rural communities were living alone or with their spouse only, therefore only one room was used among the three or four available rooms. Most of the rural elderly were living either in a traditional Korean house built with differing floor levels or in a modified Korean style house. Minimal modernization had been made for kitchen facilities such as sink and gas range or for heating facilities with the briquette boiler. However, sanitary space such as lavatory and bathroom had not been remodeled. A housing welfare program for rural communities should be implemented at the national level. The comparison of psychological characteristics of the rural elderly with their city counterparts revealed that the rural elderly have a more stable psychological status and optimistic attitude than those living in a city. However, it was found that most of the elderly did not have any future plan. Community programs for the elderly including hobbies or leisure activities or education programs to generate close interpersonal relationships with their children should be developed and provided.