誘導電動機의 單位 電流當 最大 토크 運轉에 관한 硏究

金興根,成耆冽,崔協右 慶北大學校 1990 論文集 Vol.49 No.-

This paper describes maximum torque drive of a vector controlled induction motor. As the instantaneous value of the stator current must be controlled to accomplish the superior vector control characteristic, the current controlled PWM transistor inverter with hysteresis controller is adopted. At steady-state, since the developed motor torque is proportional to the product of the flux and torque component, the motor output torque becomes maximum if the two components are equal. The system block diagram is suggested for maximum torque control. The superior characteristic of the proposed system is verified with digital computer simulation.

항공레이저측량 자료를 이용한 시가지 건축밀도 평가에 관한 연구

이근상,고덕구,조기성 한국지리정보학회 2003 한국지리정보학회지 Vol.6 No.3

본 연구에서는 최근 도시계획, 수자원 및 방재 분야에서 높은 관심을 가지고 연구중인 항공레이저측량기법을 활용하여 시가지의 건축밀도를 평가하였다. 먼저, 레이저스캐너인 LiDAR(light detection and ranging)로 취득한 표고자료로부터 DEM(digital elevation model)과 DSM(digital surface model)을 구축하였으며, 건물의 높이를 계산하기 위해 DEM에는 ZONALMEAN 필터, DSM에는 ZONALMAJORITY 필터를 적용하였다. 필터링 과정으로부터 계산한 층수와 현지조사의 층수를 비교한 결과 표준오차 ±0.199층을 확보할 수 있었다. 또한 건물 연면적 레이어와 구획레이어를 중첩하여 통계분석함으로서 도시 구획별 용적률을 제시할 수 있었다. 항공레이저측량 자료를 이용하여 계산한 용적률과 현지조사로부터 계산한 용적률의 비교 결과, 용적률의 표준오차를 ±2.68%로 확보할 수 있었다. 따라서, 항공레이저측량 자료는 향후 토지이용계획을 수립하는 의사결정자에게 매우 유용한 자료를 제공해 줄 것으로 기대한다. This study evaluated the architectural density of urban district using airborne laser scanning(ALS) that is a method used in urban planning, water resources and disaster prevention with high interest recently. First, digital elevation model(DEM) and digital surface model(DSM) was constructed from Light detection and ranging(LiDAR). For getting the height of building, ZONALMEAN filter was used in DEM and ZONALMAJORITY filter was used in DSM. This study compared the floor from filtering with the floor from survey and got standard error, which is ±0.199 floor. Also, through the overlay and statistical analysis of total-area layer and zone layer, we could present floor area ratio by zone. As a result of comparison with floor area ratio between airborne laser scanning data and survey data, the standard error of flor area ratio shows ±2.68%. Therefore, we expect that airborne laser scanning data can be a very efficient source to decision makers who set up landuse plan in near future.

운전시간이 폐수처리에 미치는 영향

최충식,하청근,권기석 7개 국립대학교 환경연구 논문집 공동발행 위원회 2002 환경연구논문집 Vol.2 No.1

The aim of the thesis is to value the features of Sequencing Batch Reactor and to discover the optimum condition by using synthetic wastewater. So as to develop the economical, efficient wastewater treatment technology which can remove substrate and nitrogen compounds by SBR Fill and Reaction time control. The results are summarized as fallows. 1. COD and T-N removal efficiency was below 95% in case of volumetric organic loading of 3㎏ BOD/㎥ day by Sequencing Batch Reactor. 2. Almost COD removed in the Fill time. 3. Various DO concentration are maximum in the Reaction time, and minimum in the Settle and Idle time. 4. COD and T-N were almost removed in Fill and Reaction time, the most suitable period was 5-3-2hr(Fill-Reaction-Settle). Removal efficiency of COD and T-N were over 98%.

電流 制御形 PWM 초퍼에 의한 磁器 浮上用 電子石 驅動에 관한 硏究

徐輔爀,全舜鏞,成耆洌 慶北大學校 1991 論文集 Vol.51 No.-

This paper designs a chopper system to drive a magnet of a magnetic levitation system. The chopper system consists of bridge type chopper with two switching devices and two freewheeling diodes. For the given system, harmonic component of source current is analyzed according to its freewheeling type. Also, its operating charateristic is analyzed by simulating the load current waveform according to the type of current controller. From the results of simulation and harmonic analysis, in terms of current controllability, current ripple and switching frequency, load freewheeling type chopper system wish ramp comparison controller is proven to be suitable. Thus the load freewheeling type chopper system with ramp comparison controller is designed and the feasibility of the proposed system is examined through experiment.

측두하악 관절의 재건을 위한 늑연골 이식의 효과

김태규,정기돈,신상훈,김성길,이성근,박상준,서종천 大韓顎顔面成形再建外科學會 1996 Maxillofacial Plastic Reconstructive Surgery Vol.18 No.3

We performed costochondral grafting in mmandibular reconstruction including condyle replacement in 5 patients which have 4 cases of ameloblastoma, 1 case of resorption of left condyle due to osteomyelitis. We harvested the 6 th costochondral cartilage of unaffected side. No specific complications were appeared with unexpected fracture of costochondral junction and infection of operation site, These patients show 30-45mm at month opening, near normal of affected side, near normal or normal of unaffected side at lateral excursion. Postoperative coureses was uneventful with improved cosmetic and functional results. Our report is indicated that the costochondral graft is satisfactory to reconstruct mandibular defect including condyle replacement, especially in growing patients.

디지털경제하에서 중소벤처기업의 활성화 전략 : e-Business의 성공전략을 중심으로

소재진,양기근 慶熙大學校 社會科學硏究院 行政硏究所 2001 行政問題硏究 Vol.8 No.1

국내육성 오차드그라스 품종들의 캘러스 형성율 및 식물체 재분화 효율

김기용,강경민,배은경,이인애,임용우,최기준,박근제,손대영,조진기 Plant molecular biology and biotechnology research 2003 Plant molecular biology and biotechnology research Vol.2003 No.-

Comparisons of callus formation ratios from seed explants, callus sizes, regeneration ratios from callus and regeneration efficiency for 4 orchardgrass (Dactylis glomerata L.) varieties (Three were developed in Korea and one was imported from foreign nation) are as follows; Jangbeol 102 (67.0%) has the highest callus formation ratio in 4 weeks incubated callus after bedding the seed explants, but Potomac (68.4%) has the highest ratio in 6-seek callus. Potomac (3.93cm) has the highest callus size in 4-week callus, but Jangbeol 101 (4.32cm) has the highest size in 6-week callus. Jangbeol 101 (17.7%) has the highest plant regeneration ratio in 4-week callus, but Potomac (37.4%) has the highest raion in 6-week callus. Jangbeol 102 (11.5%) has the highest plant regeneration efficiency in 4-week callus, but Potomac (25.6%) has the highest efficiency in 6-week callus.

補中益氣湯 투여가 장거리 달리기 선수의 에너지 및 전해질 대사에 미치는 영향 : changes in the energy and electrolyte metabolism among long distance runners

송순기,금동호,오재근,이명종 동국대학교 한의학연구소 1998 東國韓醫學硏究所論文集 Vol.7 No.1

스포츠 과학 분야에서는 운동 선수들의 경기력 향상과 운동 피로의 신속한 회복을 도모하기 위하여 한약을 복용하고 그 효과와 유의성에 대하여 연구가 활발히 이루어지고 있다. 격심한 운동을 수행할 때 나타나는 Glucose 등 에너지원의 고갈, Lactate 등 대사 산물의 축적, 전해질의 불균형 등의 여러 제반 증상이 氣虛로 인하여 나타나는 전신의 증후와 유사하다고 생각하여 補中益氣湯을 투여한 후 인체의 대사 변화를 관찰함으로서 운동수행능력에 미치는 영향과 유의성을 평가하고자 하였다. 본 연구는 장거리 달리기 선수를 대상으로 2주간의 補中益氣湯의 투여가 에너지 대사 및 전해질대사에 미치는 영향을 규명하기 위하여 최대심박수의 70% 강도의 운동을 실시한 후 운동전 안정시, 운동 직후, 휴식 후 10분, 휴식 후 30분, 휴식 후 1시간으로 나누어 혈액검사를 하였을 때 나타나는 각종 변인의 반응 양상을 비교 분석하여 유의한 결과를 얻었다. 혈중 에너지 대사에서는 free fatty acid와 Lactate 반응에서 유의성 있는 차이가 나타났고, 전해질대사에서도 Na^(+), Cl-와 K^(+) 반응에서 모누 유의성 있는 차이를 나타냈다. 그러므로 補中益氣湯은 에너지 및 전해질 대사에서 유의성있는 변화를 나타내었으며 운동수행능력의 향상에 유효하였다. Objective This experimental study was designed to investigate effects of Bo-joong-ik-gi-tang administration among long distance runners on changes of the energy and electrolyte metabolism. Materials and Methods All subjects were divided randomly with two groups, Bo-joong-ik-gi-tang Group (N=4) and control group (N=4) and performed to run the 400m track with 70% of HR max about 1 hour. The blood samples were collected from antecubital vein by 5㎖ syringes at before exercise, immediateIy after exercise, recovering- 10 min, recovering-30 min, recovering-1 hour. These sampie were used to analyze for the factors of the changes on metabolic responses. Firest, the primary factors on the changes of the energy metabolism were checked ; Glucose, Free fatty acid, Lactate, LDH. Second, the primary factors on the changes of the electroIyte metabolisrn were checked ; Na^(+), Cl^(-), K^(+). Results 1. The change of the energy metabolism 1) Glucose response was not shown significant difference between two groups. 2) Free fatty acid response in Bo-joong-ik-gi-tang group was significantly increased at recover-10 min. 3) Lactate response in Bo-joong-ik-gi-tang group was significantly decreased at immediately after exercise, recover-10 min, recover-30 min. 4) LDH response was not shown significant difference between two groups. 2. The change of the electrolyte metabolism 1) Na^(+) response in Bo-joong-ik-gi-tang group was shown significant difference between two groups at before exercise. 2) C^(-) response in Bo-joong-ik-gi-tang group was significantly increased at before exercise, immediately after exercise. 3) K^(+) response in Bo-joong-ik-gi-tang group was significantly increased at recover-10 min. Conclusion According to the above results, it was shown that Bo-joong-ik-gi-tang had the positive effects on changes of the energy and electrolyte metabolism for the long distance runners.

A Strategy for Overcoming Disaster Vulnerability and Improving Resilience - Focusing on the Conceptual Integration of Disaster Vulnerability and Resilience -

Gi Geun Yang 위기관리 이론과 실천 2016 Crisisonomy Vol.12 No.9

취약성(vulnerability)은 재난을 일으키는 위해(hazards)를 축적하고 상호작용하는 불안전한 상태에 기반 하는데 비해, 복원력(resilience)은 재난 대응에 있어서 실행되는 자원에 기반하고 있다. 복원력은 재난 이후에 일어나지만, 취약성은 재난 이전에 일어난다. 재난 발생 확률은 높은 수준의 취약성을 보이는 공동체가 더 높다. 재난으로부터의 복구는 복원력 있는 복구를 활성화시키거나 뒷받침할 수 있는 자원이 부족한 공동체에서 더 더디다. 취약성 수준을 감소시키는 것은 탄력성 있는 대응과 복구 확률을 증가시키는 경향이 있다. 그러므로 재난 취약성과 복원력 개념은 상호보완 되어져야 한다. 본 연구의 선행연구와의 차별성은 재난의 취약성과 복원력을 각각 분리된 개별적 개념으로 논의하던 것을 하나의 통합된 논의로 전환하였다는 데 있다. 본 연구는 재난의 취약성과 복원력의 개념적 통합을 시도하였고, 재난취약성과 복원력의 개념적 통합분석틀에 의거하여 우리 사회의 개인과 집단적 수준의 인적, 경제적, 사회적, 그리고 제도적 자본을 중심으로 재난취약성을 제시하고 복원력을 향상시킬 수 있는 방안을 제시하였다. While vulnerability is based on insecure conditions that build up hazards creating disasters and interact with each other, resilience is based on resources that work as a countermeasure against disasters. Resilience emerges after a disaster, but vulnerability emerges before a disaster. Disaster probability is high in communities with a high level of vulnerability. Reducing the level of vulnerability tends to increase the capability of flexible reaction and recovery probability. What differentiates this study from previous studies is the integration of disaster vulnerability and resilience which used to be discussed separately. Based on a conceptual integration of vulnerability and resilience, this study assessed the level of disaster vulnerability status in Korea focusing on human, economic, social and institutional capital at both individual and group level and suggested a strategy to improve resilience.

Socio-ecological Resilience of Hebei Spirit Oil Spill

Gi-Geun Yang 위기관리 이론과 실천 2016 위기관리 이론과 실천 학술대회 Vol.2016 No.08

This study examines social and ecological resilience following the Hebei Spirit Oil Spill from the perspective of the Ecological Impacts (oil spill itself, Marine Physical Environment, Marine Biology), Social Impacts (Disaster Management, Economy, Compensations), and Social and Ecological Resilience (Human Health and Community Resilience, Policy and Decision). The Hebei Spirit Oil accident, which occurred in 2007, inflicted severe damage on fishery, tourism, the local society and ecosystem. The accident has led to issues such as ecological devastation, disintegration of the local economy, tarnished image of the local community, deteriorating health of its residents, and various kinds of local conflicts. This study develops the theoretical framework based on previous studies. We investigate the research based on government white papers, IOPC reports, the judgment of courts, government statistics, and interviews conducted in the damaged areas. We present several suggestions on methods to restore oil spill damage. First, it is necessary to establish long- and mid-term strategies to restore the ecosystem. Second, the government and local societies need to put more effort into revitalizing the local economy within affected areas. Third, problems that come to the surface during the process of responding to the accident must be addressed.