• Journal of Chest Surgery
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• v.3 no.1
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• pp.25-30
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• 1970

• 대한위암학회:학술대회논문집
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• 2003.04a
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• pp.27-27
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• 2003

• Proceedings of the Korean Society of Radiological Science
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• 1996.06a
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• pp.31-36
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• 1996

• Composites Research
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• v.19 no.5
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• pp.1-6
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• 2006

In this study, a closed-form analysis has been developed for the transverse shear behavior of thin-walled composite beams with closed cross-sections. The shear flow distributions and cross-section stiffness coefficients are derived analytically by using a mixed beam approach. The theory has been applied to single-celled composite box-beams with elastic couplings. The location of the shear center and the effect of transverse shear deformation on the static behavior of composite beams are investigated in the framework of the analysis. The present results are validated against those of a two-dimensional finite element analysis and a good correlation has been obtained for box-beam cases considered in this study.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.312-312
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• 2023

동진강 유역은 김제평야를 품고 있어 다른 지역에 비해 농지면적이 차지하는 비중이 크며, 이에 따라 전체 용수 사용량에서 농업용수의 비중이 절대적으로 높은 유역이다. 낙양 보는 동진강 중·상류에 위치한 이수시설로 상류에 위치한 섬진강댐과 같이 동진강 유역의 농업용수 공급에 중요한 역할을 하고 있다. 낙양 보는 현재 동진강 방수문 4문, 김제간선 취입수문 2문, 정읍간선 취입수문 1문이 설치되어 있다. 관개기에는 동진강 도수로의 수문을 폐쇄하여 동진강 본류로의 하천유지용수를 차단하고 김제 배수로의 수문을 운용하여 농업용수를 공급하고 있으며 수혜구역의 용수수요 변화 및 기상상황, 하천상황에 따라 탄력적으로 운영하고 있다. 이러한 가동 보 운영으로 인하여 다양한 수위-유량관계의 변동성이 발생한다. 본 연구에서는 가동 보 운영에 따른 수위-유량관계 곡선식의 변동성을 확인하기 위해 동진강 유역 낙양보 상류에 위치한 정읍시(거산교)관측소를 대상관측소로 선정하였다. 정읍시(거산교)관측소는 2012년에 개발된 수위-유량관계곡선을 2021년까지 사용하였고, 2022년 수위-유량관계곡선식 검증과 재개발을 위하여 유량측정을 실시하였다. 2012년에 개발된 수위-유량관계곡선은 검토 결과 강우에 의한 수위 상승시 보 완전 개방 상태의 측정성과를 확보하여 수위-유량관계 곡선식을 개발하였다. 그 결과 가동 보를 운영하는 3월~9월은 상류에 위치한 정읍시(행정교)관측소와 상하류 역전 현상이 발생하였고, 매년 비정상적인 유량이 산정되는 결과를 초래하였다. 2022년 신뢰도 높은 유량자료와 수위-유량관계곡선식 개발을 위해 낙양 보 완전개방 및 부분개방에 따른 다양한 유량측정성과와 낙양 보 수문 모니터링 결과를 확보하였다. 낙양 보는 2022년 1월~3월, 10월~12월은 수문 6문을 완전 개방하여 동진강에 하천유지용수를 공급하고, 4월부터 동진강 방수문을 폐쇄하여 농번기 농업용수를 확보한 후, 5월~9월에 확보된 농용수를 김제 배수문 2문을 부분개방하면서 공급하는 방식이다. 이 기간동안 낙양 보 수문에 대한 모니터링을 위해 정읍시(거산교)관측소 수위자료에 대한 검토를 실시하였으며, 유량측정시에는 정확한 유량측정성과와 곡선식 확인을 위하여 동일한 위치에서 측정을 수행하였다. 또한, 수위 또는 유량이 변하는 구간은 연속측정을 실시하였으며, 모니터링 결과와 유량측정성과를 바탕으로 수위-유량관계 변화를 분석하였다. 그 결과 저수위1식은 수문 완전개방, 저수위2식은 수문 완전폐쇄, 저수위3~6식은 수문 부분개방 곡선식을 개발하였으며, 저수위 구간은 낙양보 운영에 따라 총 27차례 기간분리가 발생하였다. 결과적으로 본 연구에서는 낙양 보 운영에 따른 다수의 유량측정성과와 모니터링 자료를 확보하였으며, 확보한 유량측정성과의 분석을 통한 신뢰도 높은 수위-유량관계곡선식을 개발하였고 이를 통해 생산된 유량자료는 정확도가 매우 높은 것으로 분석되었다.

• 대한생식의학회:학술대회논문집
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• 2005.11a
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• pp.135-135
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• 2005

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.7
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• pp.552-559
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• 2013

In this paper, the multiple-input multiple-output (MIMO) system with a precoder is considered in the transmit-correlated Rayleigh channels. We specifically target the MIMO system employing the minimum mean square error receivers. Based on random matrix theory, we first present a direct and generalized formulation for deriving a probability density function (PDF) of the signal-to-interference-plus-noise ratio (SINR). Then, we derive the accurate closed-form SINR PDFs for a small number of transmit and receive antennas. Based on the SINR PDFs, tight closed-form approximations of the symbol error rate (SER) are derived. Our analysis suggests that the SER approximations can be used to accurately estimate the error probabilities or as a useful tool for the system design.

• Journal of Gastric Cancer
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• v.8 no.3
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• pp.148-153
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• 2008

Purpose: Malignant bowel obstruction caused by recurrent gastric cancer must be treated appropriately to improve the effects of treatment and to prolong survival. We reviewed the surgical treatments for malignant bowel obstruction caused by recurrent gastric cancer. Materials and Methods: The subjects were patients with malignant bowel obstruction caused by recurrent gastric cancer and these patients were treated by surgical procedures at our hospital from 1998 to 2008. The patients were treated by resection, ostomy or bypass. The success of treatment was decided when the patients were able to tolerate more than a liquid diet. Results: 42 patients were treated 46 times by surgical procedures. Resection was done12 times, ostomy was done 24 times and bypass was done 10 times. The hospital stay and the period to liquid diet after the operation were shorter in the ostomy group. The post operative morbidity rate was 21.7% and the post operative death rate was 8.7%. There was no significant difference in survival according to the type of surgery. Conclusion: Ostomy is good choice for selected patients because it has a shorter hospital stay and period to liquid diet. There was no significant difference in survival according to the type of surgery because curative resection is difficult to perform in patients with malignant bowel obstruction.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.10
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• pp.96-102
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• 2006

This paper presents the mechanics of the link of a double-action link-type hydraulic die set for the enclosed die forging. Operational principle of the die set in the enclosed die forging is introduced with emphasis on force transmission from the press and the hydraulic system to the material through links, die components and punches. The force exerted on the link is statically investigated and its structural analysis is carried out. The analyzed results are discussed to be used for design of the link system.

• Journal of Chest Surgery
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• v.29 no.5
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• pp.581-584
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• 1996

Reexpansion pulmonary edema is a rare complication of the treatment of lung collapse secondary to pneumothordx, pleural effusion, or atelectasis but occasionally life threatening. Generally, reexpansion pulmonary edema is believed to o cur only when a chronically collapsed lung is rapidly reexpanded by evacuation or large amounts of air or fluid. This complication is heralded by tachypnea, unilateral rales, and profuse expectoration of frothy secretion within several hours of reexpansion. Increased dur- ation of pneumothorax and the use o( suction are important factors in the generation of reexpansion pulmonary edema. We had experienced 3 cases of reexpansion pulmonary edema. In the two cases the pneumothorax had been present for several days, and, after insertion of a chest tube, pulmonary edema developed unilaterally but improved with supplemental oxygen. In the third case, massive pleural effusion was present. and, after insertion of a chest tube, pulmonary edema developed unilaterally, followed by cardiac arrest. He died of pulmonary edema inspire of resuscitation.