800㎿급 발전소 복수기의 최적 운전점 및 운전방법에 대한 연구

장철호(Cheol-Ho Jang),홍은기(Eun-Kee Hong),황광원(Kwang-Won Hwang),윤린(Rin Yun) 대한기계학회 2010 대한기계학회 춘추학술대회 Vol.2010 No.5

Along with the recent construction of a 800㎿ thermal power plant it is necessary to check the soundness of the current operation of the condenser, and to investigate the effects of vacuum level of it on the turbine efficiency for the power plant. In this study, the performances of the condenser and the turbine for the 800㎿ thermal power plant were tested based on the ASME PTC 6 and ASME PTC 12.2 with the variation of the vacuum level. When the condenser vacuum levels were 719.91 ㎜Hg, 724.5 ㎜Hg, and 729.6 ㎜Hg, the turbine efficiencies were 47.36%, 47.47%, and 47.55%, respectively. From the regression analysis of the present data, it was estimated that the optimal vacuum point is between 729 ㎜Hg and 731 ㎜Hg. When this optimal point is to be applied to the condenser, the profit of 5.5 billion won/year is expected based on the '09 caloric cost.

부산·울산·경남지역 직업병 감시체계

김정일,김병권,김정원,채창호,이철호,강동묵,김지홍,김진하,김영욱,이영하,이지호,김정호,윤형렬,유철인,정백근,장태원,김운규,윤동영,강진욱,김종은,안진홍,이동준,장준호,이광영,송혜란,최영희,이용환,조병만,최홍렬,고상백,김은아,이유진,홍영습,정갑열,김정만,김준연 大韓産業醫學會 2004 대한직업환경의학회지 Vol.16 No.1

Objective: Occupational medicine specialists in the Busan, Ulsan and Kyung-Nam areas established an area-based occupational disease surveillance system and used this system to collected case information for the purpose of preventing occupational diseases Methods: l l hospital participated in this system. The authors selected five main diseases, which were hand-arm vibration syndrome (HAVS), work-related musculoskeletal disorder (WRMSD), occupational asthma, occupational skin disease and occupational and occupational lung cancer and established their case definitions. All cases were reported on the web, and real time analysis was conducted. Results: Between April 2001 and April 2003, 192 cases of HAVS, 118 cases of WRMSD, 33 cases of occupational asthma, 17 cases of occupational skin disease and 17 cases of occupational lung cancer (for a total of 377 cases of these five main diseases) were reported. most of the HAVS cases came from shipbuilding, and 172 of them (92.7%) were associated with grinding. Of the four main types of WRMSD, carpal tunnel syndrome (CTS) was the most prevalent with 46 cases and shipbuilding was also the main industry involved (83.9%). The ergonomic risk factors involved mainly associated with the hand. In 19 (57.6%) and 4 (12.1%) cases of occupational asthma, the agents involved. The causative agents of occupational lung cancer included Cr, welding fume, PAH, Ni, etc. 10(58.8%) of the cases were diagnosed as squamous cell carcinoma and 5(29.4%) as adenoma. Conclusion: This result showed that an area-based occupational disease surveillance system might provide an effective method of evaluating the prevalence of such diseases, however the Busan, Ulsan and Kyung-Nam provinces are too large to be treated as individual areas. Therefore, the authors suggest that each province should establish its own surveillance system.

隱遁과 自適의 미학 : 南冥과 大谷

張源哲 慶尙大學校 南冥學硏究所 2002 남명학연구 Vol.13 No.-

The attitude of living in seclusion in East Asia culture has a different character from the Western one. Hermit's life in Western culture generally has a religious character to imitate Christ or Apostles, but the life in seclusion in East Asia is mostly due to social and economic reasons. Under this social and political background, a phenomenon where intellectuals-in-chief appear on a large scale who wants to live in seclusion turning their back on the world starting from 16th century in our history. The most typical people appeared in this phenomenon of 16th century are Nammyeong(南冥) Jo Sik(曺植) and Daegok(大谷) Sung Woon(成運) of all people. In case of Nammyeong and Daegok, peoples of considerable amount around or disciples following them have academic traditions and a strong nature to live in seclusion, this seems like one of the natural phenomena appearing from the initial step of conflict between Nammyeong and Deagok's ideas and study propensity and the orthodox soˇngnihak(性理學) and the following result from the actual and political ups and downs. Generally feeling the critical moment of the era itself and deal with it through Confucian disciplines and studies, those persons comparatively freely teated with fields that were regarded as a heretic by the orthodox philosophy as well as prepared their location. In result, in a standpoint of the orthodox philosophy, there were confusions in prescribing their character. However, those two people's seclusion (from the world) is sending out its color in the philosophy history of Chosuˇn because they chose hermit's life as a firm view of life from the beginning, apart from the most cases that seclusions were chosen without any choice due to a political knock-out. At the same time, its importance in philosophy history is very big in that their life aim as a hermit presents one of hermits' life aims which appear as 'a symbol of an intelligence out of power' on a large scale in our 16th century. From a historical point of view. there are two kinds of hermits. One is freedom-oriented hermits who wants to enjoy their life without any restrictions from anyone and the other one is an abstinent type of hermits selection the way of seclusion and disciplining themselves rigidly for the purpose of avoiding an extreme situation of political and social actuality. If we say Nammyeong is more approaching to abstinent type, Daegok would be close to the freedom-oriented type. After a while, this difference can be come out as a difference from their ordinary life attitude to scientific and ideal view of world or literary aesthetic sense. But the actual hermit type variously existing in the middle of these two extremes, compromising this freedom-oriented type and abstinent type. This is generally shown as a type pointing abstinence in material way and free seclusion life in spiritual way. In conclusion, Nammyeong and Daegok are the typical persons who showed hermit's life in the 16th century which appeared in earnest as an influential art of intellectuals' living. Not compromising the prevailing state of the society and the trend of that times, lived according to their belief and way with maintaining a strong spirit and belief, so they let a model of strongly independent character which are rare come into our spiritual history.

샌드블라스팅에 의한 도재의 표면처리가 브라켓의 전단결합강도에 미치는 영향

장원주,김상철 원광대학교 생체재료·매식연구소 1999 원광생체재료·매식 Vol.8 No.1

The purpose of this study was to evaluate the effect of sandblasting treatment on porcelain, on shear bond strength or bracket. This study was carried out with 192 samples which were divided into 24 groups according to 3 bonding agents and 8 surface treatment methods. Bonding agents were Ortho-oneTM, Transbond XTTM, Fuji Ortho LCTM, and surface treatment methods were differentiated by concentrations of etching agent, and use of silane or sandblasting. After surface treatment, porcelains was bonded with standard edgewise brackets and were stored in 37℃ saline for 24 hours. A universal testing machine was used to measure the shear bond strength of bracket to porcelain. The results were as follows : 1. The group which was treated with sandblasting or silane showed higher shear bond strength than the group which was treated with etching only. And the group which was treated with sandblasting, etching and silane showed the most highest shear bond strength(9.1-10.8 MPa). 2. No significant differences were found among bonding agents or concentrations of etching agent.

경식도 심초음파도의 Direct Planimetry를 이용하여 측정한 대동맥판 면적의 심박출량 및 좌심실 구출율의 변화에 따른 정확도

진승원,김종진,김희열,박지원,전두수,윤호중,박준철,노태호,채장성,김재형,홍순조,최규보 대한순환기학회 2000 Korean Circulation Journal Vol.30 No.8

행정서비스의 성과지표 및 성과측정에 관한 연구

이원장,박상철 호남대학교 2005 호남대학교 학술논문집 Vol.26 No.1

Since IMF crisis, Korean government's competitiveness among the OECD countries has been deteriorated recently. This situation indicates that our government's management system is not as efficient and effective as we expect. So the "participatory government" performs wide range of administrative innovation to solve these problems. However, the situation we face right now requires a new paradigm or strategy in public administration. The new strategy is to make government institution responsible for the people and chief executives with their results-oriented performance information and utilize the performance information in renewing policies and management practices for better government. Eventually, this approach will improve the competitiveness of our government. This study deals with the theoretical issues, such as the concept of performance while focusing on the results-oriented performance, the values of performance evaluation and performance information, issues related to the measures of performance. This study present some policy implications: First of all, we need to make the proper policy indicators which it fits on the individual policy situation. and have to give more effort to make performance indicators for generalized performance measurement, although it will be very difficult.

하계 실내 및 실외환경의 공기 중 휘발성 유기화합물 농도 및 개인노출

양원호,손부순,박종안,장봉기,박완모,김윤신,어수미,윤중섭,류인철 한국환경과학회 2003 한국환경과학회지 Vol.12 No.9

Volatile organic compounds (VOCs) are present in essentially all natural and synthetic materials from petrol to flowers. In this study, indoor and outdoor VOCs concentrations of houses, offices and internet-cafes were measured and compared simultaneously with personal exposures of each 50 participants in Asan and Seoul, respectively. Also, factors that influence personal VOCs exposure were statistically analyzed using questionnaires in relation to house characteristics, time activities, and health effects. All VOCs concentrations were measured by OVM passive samplers (3M) and analyzed with GC/MS. Target pollutants among VOCs were Toluene, o-Xylene, m/p-Xylene, Ethylbenzene, MIBK, n-Octane, Styrene, Trichloroethylene, and 1,2-Dichlorobenzene. Indoor and outdoor VOCs concentrations measured in Seoul were significantly higher than those in Asan except Ethylbenzene. Residential indoor/outdoor (I/O) ratios for all target compounds ranged from 0.94 to 1.51 and I/O ratios of Asan were a little higher than those of Seoul. Relationship between personal VOCs exposure, and indoor and outdoor VOCs concentrations suggested that time-activity pattern could affect the high exposure to air pollutant. Factors that influence indoor VOCs level and personal exposure with regard to house characteristics in houses were building age, inside smoking and house type. In addition insecticide and cosmetics interestingly affected the VOCs personal exposure. Higher exposure to VOCs might be caused to be exciting increase and memory reduction, considering the relationship between measured VOCs concentrations and questionnaire (p<0.05).

중압 배전망에서의 전력선 통신을 위한 OFDM 기법의 성능 분석

임장규,김산해,장희동,이원철,신요안 崇實大學校 生産技術硏究所 2002 論文集 Vol.32 No.-

Recently, PLC (Power Line Communication) on medium voltage power lines have been gaining much attention for high data rate access networking. In this paper, we evaluate the performance of OFDM (Orthogonal Frequency Division Multiplexing) schemes on medium voltage power line channels in the frequency range up to 20 ㎒. We analyze fading characteristics of multi-path channel models for medium voltage power lines, and simulations have been carried out for the OFDM using adaptive bit loading scheme. Simulation results indicate that the OFDM schemes with the adaptive bit loading show good bit error rate performance under harsh medium voltage power lines channel.

인공망막칩과 형상기억합금을 이용한 평활 안구운동시스템 구현

김원철,김현수,박종호,박대식,이민호,신장규 한국뇌학회 2001 한국뇌학회지 Vol.1 No.2

본 논문에서는 인간의 평활 추적안구운동을 모방하는 능동시각시스템(active vision system)을 구현하였다. 평활 추적 안구운동을 모방하는 능동시각시스템을 구현하기 위해 인간의 안구운동 중에 관찰되는 신경생리학적인 특징들을 이해하고, 다양한 안구운동 중에서 평활 추적안구운동 중에 관찰되는 중측관자(medial temporal) 세포의 역할을 자기조직화 형상지도(self-organizing feature map)와 승자독점(winner take all)을 이용하여 구현하였다. 회전속도계 궤환 모델(tachometer feedback model)로 중상측관자(medial superior temporal) 세포의 역할을 모델하였다. 그리고 인공망막칩으로 인공 안구를 구성하고 형상기억합금 구동기(actuator)를 이용하여 인공 안근육을 구성하여, 빛의 밝기 변화인 윤곽(edge) 정보에 반응하는 인공 안구모형을 제작하였으며, 실험을 통하여 시스템의 동작성능을 보였다. In this paper, we proposed a model of smooth pursuit eye movement, and developed a human-like active vision system using a retina chip and a shape memory alloy actuator. The model of smooth pursuit eye movement is to imitate the role of MT and MST area of human brain in smooth pursuit eye movements. We fabricated the 8×8 retina chip for the edge detection. The developed retina chip is an image sensor to extract edge information and the shape memory alloy actuator is a driver to imitate the role of eye muscles to follow a moving object.

심실 조기 수축의 발생 부위 및 연결 간격의 차이에 따른 혈역학적 변화

진승원,김재형,노태호,조은주,김희열,이만영,김종진,박준철,채장성,홍순조,최규보 대한순환기학회 1999 Korean Circulation Journal Vol.29 No.7