• 기술사
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• 제15권4호
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• pp.12-24
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• 1982

East Parts of Bangladesh have been benifited by low cost energy generated by domestic natural gas but West parts where energy generated by imported fuel. Bangladesh Government authority has very much concerned to transmit the low cost electricity to the West from the East for past several years. To solve such concerns, cross-country 230kv double circuits Power transmission line was proposed, however there was a big obstacle for the realization of this line to cross the Jamuna river which has 12 km long width with a deep muddy river bed. A consultant engineering firm named Merz-Mclellan anyway finalized this plan and a world-wide bid was announced on June 31, 1979. Due to the expected difficulty to construct the towers on sea like area, only three construction groups have participated. including a Korean joint venture organization of Samsung-Korean Developement corporation-Kolon Electric Machinery company. After 3 months bid evaluation, contract was awarded to Korean Consosium and KEM Co was in charge of designing steel towers with anchor bolts and base plates beside to electrical engineering field. Then KEM Co have faced and over-comed many unenpected technical difficulties such as forced eccentricity joint on base plate, distorsion issue of 60mm thick plates welding, threading anchor bolts, tad heat treatment of some anchor bolts, disagreement from Consultant Engineer on multiplying factor of leg stresses for 45$^{\circ}$ wind and on reducing O.L.F for wind loads on cables for such 1220km long spans. After spending two years long period for designing and engineering towers, base plates, and anchor bolts, first shipment of tower was finally realized on Nov. 8, 1981 and on the other hand KDD has proceeded concrete caisson work on schedule at Jamuna river site and expected to complete tower erection and stringing of cables within this year of 1982 which was original completion target.

• 한국해안해양공학회지
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• 제1권1호
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• pp.93-101
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• 1989

본 논문에서는 가이드 타워, 텐션 레그 프랫폼, 무어링 부이, 해저 케이블, 사장교, 현수교, 케이블 루프 등과 같은 해상 및 육상 구조물의 유한요소 모델에 사용하기 위한 기하학적 비선형 케이블 요소를 연구 제시하였으며, 케이블 요소는 평면내에서 임의의 하중과 기하형상을 갖는 케이블에 대한 탄성현수 케이블 이론으로부터의 적합방정식과 연성행렬을 직접 이용하여 유도하였다. 또한, 유도된 케이블 유한요소에 근거하여, 케이블 부재를 사용하는 구조물들의 유한요소 해석을 위해 전산 프로그램을 개발하였으며, 시간영역 동적 해석을 위해 뉴마크-베타의 직접적분법을 사용하였고, 각 시간간격에서의 비선형 평형방정식 및 적합방정식을 풀기 위한 방법으로서 뉴톤-랩슨의 반복법을 사용하였다. 이상과 같이 개발된 전산 프로그램을 이용하여 케이블 부재에 대한 정적 및 동적 해석을 수행한 후 그 결과를 분석ㆍ고찰하여 보았다.

• 대한핵의학회지
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• 제24권1호
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• pp.108-118
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• 1990

It is well known that the glucocorticoid suppresses the osteoblast and the calcitonin suppresses the osteoclast. If the calcitonin prevents the osteoporosis with increased Tc-99m MDP uptake in the long-term use of glucocorticoid, then the calcitonin has some activating effect on the bone formation. The immobilization operation was done on the left hind-leg of 16 male Sprague-Dawley rats weighing about 300 g each. For 12 weeks after operation,8 rats were injected 0.5 mg/kg dexamethasone, and the other 8 rats were injected 0.5 mg/kg dexamethasone and $1\;\bar{u}/kg$ eel calcitonin. The bone mineral content was measured by the single photon absorptiometry and the Tc-99m MDP uptake was used as an index of the osteoblastic activity. 1) The Tc-99m MDP uptakes in the dexamethasone treated group were lower than those in the dexamethasone and calcitonin treated group, and there was no significant difference in Tc-99m MDP uptakes between the immobilized and normal femurs. 2) The bone mineral contents in the dexamethasone treated group were significantly lower than in the dexamethasone and calcitonin treated group, and the immobilized femurs had tower BMC than normal femurs. 3) The slope of regression between the BMC and Tc-99m MDP uptake was stiff in the dexamethasone treated group, and flat in the dexamethasone and calcitonin group, which shows discrepancy between the bone resorption and formation resulting prevention of net bone loss in the dexamethasone and calcitonin treated group. In conclusion, the calcitonin has some effect on the bone formation, and further studies with urinary hydroxyproline and cyclic AMP are expected.