• 소성∙가공
• /
• 제5권2호
• /
• pp.97-104
• /
• 1996

It is very important to obtain the knowledge of loads and flow patterns in most processes because these information are the fundamental data of die design and process design. The objective of present study is to investigate loads and metal flow patterns for various process conditions in flat die extrusion of square-bars from circular billets. For analyzing the metal flow patterns of the billets photo etching is used on sections of split specimen. From this method metal flow patterns are analyzed for various area reductions friction factors and punch stroke through the process from initial-stage to final-stage. Experiments are carried out with hard solder billets at room temperature.

• 한국지진공학회:학술대회논문집
• /
• 한국지진공학회 2003년도 추계 학술발표회논문집
• /
• pp.288-294
• /
• 2003

Increasing the volume of traffic on the roads causes social and economical problems such as increasing air-pollution and distribution cost. Prefabricated light weight bridge becomes a possible solution for these problems in the urban area where it is difficult to construct new one or expend the existing road. There are some merits in this kind of bridge. First, the design live and dead loads are minimized by allowing only passenger cars. Second employing prefabrication construction scheme reduces the construction time. Third, there is no need to buy land if the elevation road is placed on the top of existing one. In seismic design of bridges, base isolation has been an effective solution when the bridge has stiff piers and a heavy superstructure. The prefabricated light weight bridge has different dynamic characteristics from the ordinary bridges. In this paper, the applicability of base isolators such as lead rubber bearing and elastomeric bearing, to prefabricated light weight bridge is examined.

• Bulletin of the Korean Chemical Society
• /
• 제12권1호
• /
• pp.87-92
• /
• 1991

A dual capillary column system is described for the simultaneous measurement of retention index (RI) and area ratio (AR) values of each peak on two capillary columns of different polarity, DB-5 & DB-1701. Both capillary columns were connected to a common splitless injector via a deactivated fused-silica capillary tubing of 1 m length and a 'Y' splitter, the dead volume effect of which was found to be negligible. RI and AR were measured with high reproducibility(${\leq}$0.05% RSD) and with high accuracy (<10% RE), respectively. When applied to the test samples of the organic acid mixture, each acid was positively identified by the combined computer RI library search-AR comparison.

• Archives of Plastic Surgery
• /
• 제48권3호
• /
• pp.329-332
• /
• 2021

Calcific myonecrosis is a rare condition in which hypoperfusion due to compartment syndrome causes soft tissue and muscle to become calcified. As calcific myonecrosis gradually deteriorates, secretions steadily accumulate inside the affected area, forming a cavity that is vulnerable to infection. Most such cases progress to chronic wounds that are unlikely to heal spontaneously. After removing the calcified tissue, the wound can be treated by primary closure, flap coverage, or a skin graft. In this case, a 72-year-old man had extensive calcific myonecrosis on his left lower leg, and experienced swelling and increasing tenderness. After removing the muscle calcification, we combined two anterolateral thigh free flaps, which were harvested from the patient's right and left thigh, respectively, to reconstruct the wound with a dead-space filler and skin-defect cover at the same time. The patient recovered without revision surgery or major complications.

• 디지털융복합연구
• /
• 제12권8호
• /
• pp.35-47
• /
• 2014

카지노 관련 정책에 대한 정성적인 방법으로 한 주민의식 분석으로 기대도, 지지도, 적정도, 인지도, 참여도, 기여도, 수혜도를 분석한 주요 결과는 다음과 같다. 첫째, 카지노 관련 정책에 대한 재정지원 및 규제완화혜택 인식도(인지도 III)가 가장 높고, 수혜도와 기여도 II 순으로 높게 나타났다. 이 결과 지금까지 폐광지역 진흥정책에 대해 관심 있게 지켜보았으나 그 효과는 기대에 못 미치는 것으로 나타났다. 현재 추진하고 있는 2단계 사업과 폐광개발기금을 대체산업육성자금으로 활용하는 방안이 주민의 요구로 판단된다. 둘째, 카지노 관련 정책에 대한 비교 평가에서 진흥 정책 인지도와 지역발전 기여도, 참여도와 지역발전 기여도, 수혜도와 지역발전 기여도, 폐광지역진흥정책 참여도와 지역균형발전 기여도, 수혜도와 지역균형발전 기여도 등의 관계를 분석한 결과 모든 관계 사이에 관련성이 존재하는 것으로 분석되었다.

• 화약ㆍ발파
• /
• 제31권2호
• /
• pp.14-24
• /
• 2013

도심지에서 암반 제거 작업에 시공되어 온 방법 중 가장 효과적인 방법은 소량의 화약류를 사용하여 장약 전색한 후 발파하여 암반에 균열을 발생시켜 암석을 제거하는 방법인데, 환경적인 요인으로 인하여 그 사용에 제한을 받는 경우가 많아지고 발파 불가 지역이 늘어나고 있는 실정이다. 이 공법은 암반에 천공된 공속에 장약을 할 때 전색보호판을 이용하고 같은 시차의 뇌관과 화약으로 다단 장약/전색하고 다단발파기를 이용하여 최적화 된 정밀제어를 함으로써 진동을 감소시켜 발파하는 다단식분산발파 방법으로 모든 현장에 사용 가능하지만 특히 진동과 관련된 분쟁이 큰 도심 지역의 암반 제거에 있어서 더 효과적으로 사용할 수 있다. 이 공법은 일반적으로 천공되어지는 짧은 천공장(1.2~3.0미터)으로 인해 다단 장약 후 지연 기폭이 힘든 구간에서도 뇌관선이 단락 되거나 폭발화약 주변의 화약이 사압을 받는 일이 없이 쉽게 발파패턴을 설계하여 사용 할 수 있다.

• Archives of Plastic Surgery
• /
• 제32권2호
• /
• pp.183-188
• /
• 2005

Defect on the temporal area caused by, surgical ablation of a tumor or an infection should be reconstructed immediately to prevent potentially life-threatening complications such as meningitis and cerebrospinal fluid leakage. The defect on the temporal area usually presents as a typical 'cone-shape'. Successful reconstruction requires sufficient volume of well-vascularized soft tissue to cover the exposed bone and dura. From 1994 through 2003, the authors applied rectus abdominis free flap for the reconstruction of the temporal defect from 1994 through 2003. There were 10 patients with a mean age of 52.1 years. Of these 10 patients, external auditory canal cancer was present in four patients, temporal bone cancer in two, parotid gland cancer in one and three patients were reconstructed after debridement of infection(destructive chronic otitis media). All the free flaps survived, and flap-related complications did not occur. Compared to a local flap, the rectus abdominis free flap can provide sufficient volume of well-vascularized tissue to cover the large defect and can be well-tolerated during an adjuvant radiation therapy. The long and flat muscle can be easily molded to fit in to the 'cone-shape' temporal defect without dead space. It is also preferred because of the low donor site morbidity, a large skin island and an excellent vascular pedicle. Two-team approach without position change is possible. In conclusion, the authors think that rectus abdominis free flap should be considered as one of the most useful method for the reconstruction of a cone-shaped temporal defect.

• 대한두경부종양학회지
• /
• 제25권1호
• /
• pp.39-42
• /
• 2009

Wide excision for curative treatment of malignant tumor on periauricular area often leads to loss of the external ear. But the auricle has rich vascular supply, Conservation of auricular contour is possible through salvage and engineering of remained auricular tissue. We experienced two cases of auricular salvage after wide excision of malignant tumor. In the first case, we performed two-staged technique. In first step, we covered soft tissue defect on periauricualr area with the anterolateral thigh free flap and remained auricle was floating over the flap after split-thickness skin graft was applied on it's posterior raw surface because it's survival was not confirmed. Second step was reposition of remained auricule on the anterolateral thigh flap. In the second case, we packed in periauricular dead space and external auditory canal with temoporalis muscle and temporoparietal fascial flap and then covered the flap with split thickness skin graft. In these two cases, there were no recurrence of tumors and we obtained cosmetically & functionally satisfactory results.

• 한국환경복원기술학회지
• /
• 제4권3호
• /
• pp.66-74
• /
• 2001

The main purpose of this thesis is to select the appropriate plants for the ecological restoration of coastal land. The soil and vegetation environment survey of the beach where the halophytes live now was executed for the sake. Firstly, the soil survey was done by the physical and chemical survey of beach soil and dumped soil. The soil is mostly sandy loam and sandy clay loam which has silty much. The beach soil where the salt plants live has more organic matters in the content than dumped soil because of the influx of the dead halophytes, a pioneer plant to this area. Secondly the vegetation survey was executed by the halophytes survey in the beach area in order to select the appropriate plants for ecological restoration. The shows two different areas in the vegetation divided by the salt density of soil. Artemisia fukudo, Juncus haenkei, Carex pumila, Silene armeia, Polyponum aviculare etc live in the less salt density area and it doesnt show collected. Salicornia herbacea, Suaeda asparagoides, Aster tripolium, Limonium tetragonum, Suaeda maritima, Scirus fluvitilis, Phragmtes communis, Suaeda japonica, Zoysia sinica etc halophytes live in the more salt density area and there are a few advent plant but many collected. So the salt density of soil limits the vegetation. The selection of appropriate plants for the ecological restoration programs was designed with 3 different standards considering the salt density of soil in the dumped soil area. The plan selection guidelines of thick salt density due to the salt density of soil, and economical efficiency and maintenance because the area is large. The guidelines of middle salt density area were made considering economical efficiency and maintenance because there are salt as well, and it is effective for the scenery if they have normal ecology but their leaves have good color and the flowers are beautiful. However I suggest beautiful flowery plants for the neutral plan area because this area is the entry point of the airport so the view is very important.

• 한국ITS학회 논문지
• /
• 제19권1호
• /
• pp.94-106
• /
• 2020

근래의 위치 측위 방법으로 GPS(Global Positioning System) 위성정보를 활용하는 전파항법 방식을 많이 사용하고 있다. GPS 활용범위가 넓어지고 다양한 측위 정보를 기반으로 하는 분야가 생기면서 보다 높은 정확도를 얻기 위한 새로운 방법들이 요구되고 있다. 자율주행차의 경우 IMU(Inertial Measurement Unit)를 사용한 항법 시스템인 INS(Inertial Navigation System)와 차량 내부 센서를 이용한 DR(Dead Reckoning) 알고리즘을 사용하여 GPS의 정확도 저하나 음영지역에서의 위치 측정방법으로 사용하고 있다. 그러나 이러한 측위 방법은 대형화되는 빌딩 지역, 터널, 지하 주차장 등 다양한 음영지역과 시간이 지남에 따라 오차가 계속 증가하는 누적 기반 위치추정 방법의 한계로 인해 많은 문제 요소가 있다. 본 논문은 GPS 음영지역에서 차량의 위치 측위를 위해, 대중적 무선 통신인 WLAN을 이용한 Fingerprint 기법을 4개의 Anchor 형태로 AP(Access Point)와 지향성 안테나를 위치하여 넓은 지하 주차공간에서 효율적인 측위 방법을 제시하고 시간이 지남에 따라 주차된 차량이 이동하는 환경에서도 변화가 없는 위치 측위 결과를 입증하였다.