• International Journal of Fluid Machinery and Systems
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• 제10권2호
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• pp.146-153
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• 2017

Sediment flow through hydropower components causes hydro-abrasive erosion resulting in loss of efficiency, interruptions in power production and downtime for repair/maintenance. Online instruments are required to measure/capture the variations in sediment parameters along with collecting samples manually to analyse in laboratory for verification. In this paper, various sediment parameters viz. size, concentration (TSS), shape and mineral composition relevant to hydro-abrasive erosion were measured and discussed with respect to a hydropower plant in Himalayan region, India. A multi-frequency acoustic instrument was installed at a desilting chamber to continuously monitor particle size distribution (PSD) and TSS entering the turbine during 27 May to 6 August 2015. The sediment parameters viz. TSS, size distribution, mineral composition and shape entering the turbine were also measured and analysed, using manual samples collected twice daily from hydropower plant, in laboratory with instruments based on laser diffraction, dynamic digital image processing, gravimetric method, conductivity, scanning electron microscope, X-ray diffraction and turbidity. The acoustic instrument was able to capture the variation in TSS; however, significant deviations were found between measured mean sediment sizes compared to values found in the laboratory. A good relation was found for turbidity ($R^2=0.86$) and laser diffraction ($R^2=0.93$) with TSS, which indicated that turbidimeter and laser diffraction instrument can be used for continuous monitoring of TSS at the plant. Total sediment load passed through penstock during study period was estimated to be 15,500 ton. This study shall be useful for researchers and hydropower managers in measuring/monitoring sediment for hydro-abrasive erosion study in hydropower plants.

• 한국생산제조학회지
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• 제23권1호
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• pp.94-101
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• 2014

Recently, in order to reduce the time required to replace an optical jumper cord, many researchers are using a field-installable connector and applying the ferrule polishing method, ferrule mechanical contact method, or ferrule fusion contact method. However, the process of arranging the length of the optical fiber, i.e., inserting the optical fiber into the ferrule by hand and checking its cross section, takes 60% of the time required for the entire process, which increases the overall cost. Therefore, in order to make this task more cost-effective, we will develop an automated inspection system with automatic cross-sectional arrangement of a field-installable connector. This system will be able to decrease the failure rate from 10% to 2% compared with the conventional method when cutting the optical fiber inserted into the ferrule. It will also improve the productivity by decreasing the test time by 28% compared with the conventional method. Our studies showed that it was possible to reduce the production costs and improve the quality of a field-installable connector, and we expect it to dominate the market.

• 한국공간정보시스템학회:학술대회논문집
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• 한국공간정보시스템학회 2007년도 GIS 공동춘계학술대회 논문집
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• pp.246-251
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• 2007

The purpose of this study is to develop a grid based model for calculating the critical nonpoint source (NPS) pollution load (BOD, TN, TP) in Nak-dong area in South Korea. In the last two decades, NPS pollution has become a topic for research that resulted in the development of numerous modeling techniques. Watershed researchers need to be able to emphasis on the characterization of water quality, including NPS pollution loads estimates. Geographic Information System (GIS) has been designed for the assessment of NPS pollution in a watershed. It uses different data such as DEM, precipitation, stream network, discharge, and land use data sets and utilizes a grid representation of a watershed for the approximation of average annual pollution loads and concentrations. The difficulty in traditional NPS modeling is the problem of identifying sources and quantifying the loads. This research is intended to investigate the correlation of NPS pollution concentrations with land uses in a watershed by calculating Expected Mean Concentrations (EMC). This work was accomplished using a grid based modelling technique that encompasses three stages. The first step includes estimating runoff grid by means of the precipitation grid and runoff coefficient. The second step is deriving the gird based model for calculating NPS pollution loads. The last step is validating the gird based model with traditional pollution loads calculation by applying statistical t-test method. The results on real data, illustrate the merits of the grid based modelling approach. Therefore, this model investigates a method of estimating and simulating point loads along with the spatially distributed NPS pollution loads. The pollutant concentration from local runoff is supposed to be directly related to land use in the region and is not considered to vary from event to event or within areas of similar land uses. By consideration of this point, it is anticipated that a single mean estimated pollutant concentration is assigned to all land uses rather than taking into account unique concentrations for different soil types, crops, and so on.

• 대한교통학회지
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• 제17권2호
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• pp.115-126
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• 1999

과거 우리는 자연의 현상을 파악하고 분석하여 장래를 예측하기 위한 수단으로 분야별로 다양한 연구를 수행해 왔다. 교통 이론에 있어서도 기존에 제시되었던 많은 이론들이 수정과 보완과정을 거치면서 발전되는가 하면 그렇지 못한 이론들은 한계를 극복하지 못하고 소멸되어 갔다. 이러한 원인중의 하나가 교통류속의 카오스 현상 발견이었다. 교통류의 카오스 발생은 크게 교통량 감소의 원인이 되거나 시뮬레이션 결과의 신뢰성을 저하시키는 원인이 된다. 또한 카오스 이론에서 제시하는 나비효과등으로 인하여 교통모형 정립에 있어서 예측의 한계를 보여줌으로써 카오스 발생이 교통계획에 있어서 장기적인 예측을 어렵게 하는 이유가 되기도 한다. 따라서 교통류 속에서 카오스 현상을 제거하거나 규명할 수 있는 방안이 마련되어야 이러한 한계를 극복할 수 있다는 것이다. 이러한 의도하에 본 연구에서도 기존의 교통류 이론들의 한계와 개선을 위한 새로운 접근 방안을 제시하였으며, 사례로는 카오스 이론을 활용한 링크통행시간 추정을 적용하여 보았다.

• 대한한의학방제학회지
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• 제21권2호
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• pp.1-12
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• 2013

Objectives : Systematize concept of 'Saengsukron(生熟論)', providing theoretical basis for clinical and research purpose. Methods : Herbal medicines listed in 'Tangaekpyeon of Dongeuibogam' were studied in the following order ; (i) Search for herbal medicines that has applied heat. (ii) Choose herbal medicine with reference of change before and after heating. And choose herbal medicine with reference on purpose of heating. (iii) Classify herbal medicines with similar patterns. (iv) Catagorize herbal medicine by its effects, side effects, nature of herbal medicines, tastes of herbal medicines, meridian tropism of the herbal medicines, and others(color of herbal medicines, formation of herbal medicines, storage of herbal medicines) (v) Systematize concept of 'Saengsukron'. Results : We were able to obtain systematized concept of 'Saengsukron(生熟論)'. They are classified by 'Saengsasukbo(生瀉熟補)', 'Saenghwalsukji(生活熟止)', 'Saengmusukyu(生無熟有)', 'Sukjeukhyojeung(熟則效增)', 'Sukjeukhyogam(熟則效減)', 'Sukjeukyudok(熟則有毒)', 'Saengdoksukgam(生毒熟減)', 'Saengjunsukwan(生峻熟緩)', 'Saengchangsukso(生脹熟消)', 'Sukjeukwiseong(熟則爲升)', 'Sukjeukwigang(熟則爲降)', 'Sukjeukwion(熟則爲溫)', 'Sukjeukwiryang(熟則爲凉)', 'Saengjosukgam(生燥熟減)', 'Sukjeukbyeonmi(熟則變味)', 'Sukjeukbyeonchwi(熟則變臭)', 'Sukjeukbui(熟則部異)', 'Sukjeukjongsa(熟則從邪)', 'Sukjeukbyeonsaek(熟則變色)', 'Sukjeukbyeonhyeng(熟則變形)' and 'Sukjeukbojang(熟則保長)'. Conclusions : In this study, heat processing of herbal medicines confirmed that certain regular changes occur. Based on this, concept of 'Saengsukron' could be systematized. Research on 'Saengsukron' will help practitioners and researchers.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1080_1081
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• 2009

This paper proposes a cooling system using self tuning PI controller for improving the output of BIPV module. The temperature characteristics in regard to improving the output of BIPV system has rarely been studied up to now but some researchers only presented the method using a ventilator. The cooling system efficiency of BIPV module applied to a ventilator mainly depends on the weather such as wind and insolation etc. Because the cooling system of BIPV module using a ventilator is so sensitive, that is being set off by wind speed at all time but is unable to operate in the nominal operating cell temperature(NOCT) which is able to make the maximum output. The paper proposes the cooling system using thermoelectron by self tuning PI controller so as to solve such problems. The thermoelectron control of self tuning PI controller can be controlled independently in the outside environment because that is performed by micro-controller. The temperature control of thermoelectron, also, can be operated around NOCT through algorism of the temperature control. Therefore, outputs of the whole system increase and the efficiency rises. The paper demonstrates the validity of proposed method by comparing the data obtained through a experiment of the cooling method of BIPV using a ventilator and proposed thermoelectron

• 한국콘텐츠학회논문지
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• 제14권2호
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• pp.283-293
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• 2014

본 연구의 목적은 "8만 시간 디자인 공모전"에 제출된 에세이를 활용하여 베이비부머가 갖고 있는 노후에 대한 인식과 기대를 살펴보는 것이다. 2011년 첫 공모전에 참여한 인원 중에서 베이비부머 세대에 해당하는 62명분의 에세이 자료를 주제중심분석(thematic analysis)방법으로 분석하였다. 연구결과 첫째, 베이비부머 참여자들은 공모전을 통해 노후준비를 한다는 것의 의미를 재발견하고 있었다. 둘째, 이들이 계획하는 노후는 세 가지 모습으로 도출되었다: 1) 나 자신에게 집중된 삶, 2) 일과 관계, 여가가 조화롭게 연계된 삶, 3) 사회환원적인 창출을 꿈꾸는 공동체의 삶. 셋째, 참여자가 꼽은 필수 노후준비 사항은 건강관리와 배움의 기회를 적극적으로 활용하는 것이다. 그런데 베이비부머 참여자들은 노후준비에 있어서 성실하지만 약간 강박적인 모습을 보인다. 본 연구를 통해 베이비부머의 노후생활과 노후준비에 대한 구체적이며 현실적인 방안에 도움이 되는 지원 방향을 제공하였다.

• 대한의용생체공학회:의공학회지
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• 제28권4호
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• pp.494-502
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• 2007

Ubiquitous location based services (u-LBS) will be interested to an important services. They can easily recognize object position at anytime, anywhere. At present, many researchers are making a study of the position recognition and tracking. This paper consists of postion recognition and user identification system. The position recognition is based on location under services (LBS) using a signal strength map, a database is previously made use of empirical measured received signal strength indicator (RSSI). The user identification system automatically controls instruments which is located in home. Moreover users are able to measures body signal freely. We implemented the multi-hop routing method using the Star-Mesh networks. Also, we use the sensor devices which are satisfied with the IEEE 802.15.4 specification. The used devices are the Nano-24 modules in Octacomm Co. Ltd. A RSSI is very important factor in position recognition analysis. It makes use of the way that decides position recognition and user identification in narrow indoor space. In experiments, we can analyze properties of the RSSI, draw the parameter about position recognition. The experimental result is that RSSI value is attenuated according to increasing distances. It also derives property of the radio frequency (RF) signal. Moreover, we express the monitoring program using the Microsoft C#. Finally, the proposed methods are expected to protect a sudden death and an accident in home.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제12권3호
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• pp.183-191
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• 2006

생물학 분야에서 유전자에 대한 연구가 활발하게 이루어지면서 유전자에 대한 정보 구축 및 통합에 대한 필요성이 대두 되었다. 그 결과 Gene Ontology Consortium은 W3C에서 제정한 온톨로지 기술언어인 OWL로 유전자에 대한 정보와 분류를 담고 있는 Gene Ontology를 구축하였다. 하지만 Gene Ontology를 위한 기존의 브라우저들은 키워드, 트리, 그래프 기반의 단순 검색만을 지원할 뿐 다양한 관계를 고려한 고급 정보 검색이 불가능하다. 본 논문은 실제 생물학 연구를 수행하는 사용자들이 Gene Ontology를 효과적이고 편리하게 사용할 수 있도록 하기 위해 다양한 온톨로지 검색 기법을 통합적으로 지원하는 방법을 제안하였다. 또한 질의어 입력대신 검색 중에 손쉽게 질의를 생성하는 기법과 생성된 질의를 SeRQL 질의로 변환하는 기법을 제안함으로써 온톨로지에서 지원하는 질의어에 독립적으로 손쉽게 질의를 생성하고 고급정보를 얻을 수 있도록 하였다. 그리고 이렇게 구축한 GO Guide 브라우저를 통해 Gene Ontology의 방대한 정보를 효과적으로 이용할 수 있음을 확인하였다.

• 대한한의학원전학회지
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• 제27권4호
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• pp.29-38
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• 2014

Objectives : In ministerial-fire theory(相火論) of Zhu Dan-Xi(朱丹溪), the meanings of monarch-fire(君火) and ministerial-fire(相火) described in papers published nowadays are not the same. Therefore, it is necessary to rebuild a clear concept. Methods : To understand the relationships among 'heaven(天)'-'human(人)' and 'name(名)'-'position(位)', the core concept of the ministerial-fire theory(相火論) of Zhu Dan-Xi(朱丹溪), I examined the relationships between 'heaven(天)' and 'human(人)' in Neo-Confucianism(性理學) of Song(宋) Dynasty and reviewed the notes of Wang Bing(王冰) which were quoted by Zhu Dan-Xi(朱丹溪) to set the concept of monarch-fire(君火) and ministerial-fire(相火). I studied relevant texts. Results : In ministerial-fire theory(相火論) of Zhu Dan-Xi(朱丹溪), monarch-fire(君火) is perceived as being from greed(人欲) that can cause hyperactivity(妄動) of ministerial-fire(相火), whereas ministerial-fire(相火) is perceived as being able to control monarch-fire(君火) by following the orders from heaven. This point of view is different from the past which recognized monarch-fire (君火) as the owner and ministerial-fire(相火) as the servant. Conclusions : Zhu Dan-Xi(朱丹溪) received the ideological impact of Neo-Confucianism, and accepted the notes of Wang Bing, recognized monarch-fire(君火) as 'name(名)' and ministerial-fire(相火) as 'position(位)', so he voiced the ministerial-fire theory(相火論) that perceived monarch-fire(君火) as fire(火) of the five processes(五行) of human body that came from greed, ministerial-fire(相火) as being in a position to hear the order from the 'heaven(天)' to control monarch-fire(君火). But the concept of ministerial-fire(相火) which he set connoted a confusing meaning of 'nature(性)' and 'way(道)' of Neo-Confucianism. In the later process to solve the problem, life-gate theory(命門學說) was raised, and many researchers had tried to remove the meaning of hyperactivity from the ministerial-fire(相火).