목적 : 각막굴절교정수술 후 저평가되는 안압을 다양한 각막 절삭량에 따라 경도, 중등도, 고도 근시 군을 나누어 조사하고, 각 군별로 가장 적합한 수술 후의 안압 보정방법을 제시하고자 하였다. 방법 : 각막굴절교정수술을 받은 평균 연령 26.89±5.18세의 남녀 501명 1,002안(남자 237명, 여자 264명)을 대상으로 하였다. 안압은 비접촉식 안압계를 이용하여 측정하였고, 수술 후 저평가된 안압을 보정하기 위해 Ehlers, Shah, Dresden, Orssengo/Pye의 보정방법을 이용하였다. 다양한 각막 절삭량에서의 안압 차이를 비교하기 위해 세 그룹으로 나누어 분석하였다. 결과 : 비접촉식 안압계로 측정한 수술 전 안압은 15.67±2.39 mmHg이었고, 수술 후 안압은 10.12±2.11 mmHg로 평균 5.55±2.09 mmHg 만큼 유의하게 낮게 측정되었다. Ehlers의 보정방법으로 산출된 수술 후의 안압은 14.53±2.47 mmHg로 수술 전 안압과 평균 1.14±2.83 mmHg 차이를 보여 네 가지 보정방법 중에서 수술 전 안압 측정치와 가장 비슷한 수치를 보였다. 또한 각막 절삭량에 따라 나눈 경도, 중등도, 고도근시 각 군 모두에서 Ehlers 식으로 보정된 안압이 수술 전 안압과 차이가 가장 적게 나타났다. 결론 : 굴절교정수술 후 고도근시를 포함한 다양한 근시군 모두에서 4가지 보정방법 중 Ehlers 보정법이 가장 유용한 것으로 판단된다. 이 결과는 각막굴절교정수술 후 저평가되는 안압의 실제 값을 산출하여 녹내장에 대한 조기진단 및 치료시기가 늦어지는 것을 막는 데에 활용할 수 있을 것이라 생각된다.

Rapid industrial development in recent times has increased the demand for light-weight materials with high strength and structural integrity. In this context, carbon fiber-reinforced plastic (CFRP) composite materials are being extensively used. However, laminated CFRPs develop faults during impact because CFRPs are composed of mixed carbon fiber and epoxy. Moreover, their fracturing behavior is very complicated and difficult to interpret. In this paper, the effect of the direction of lamination in CFRP on the absorbed impact energy and impact strength were evaluated, including symmetric ply (0°/0°, –15°/+15°, –30°/+30°, –45°/+45°, and –90°/+90°) and asymmetric ply (0°/15°, 0°/30°, 0°/45°, and 0°/90°), through drop-weight impact tests. Further, the thermal properties of the specimens were measured using an infrared camera. Correlations between the absorbed impact energy, impact strength, and thermal properties as determined by the drop-weight impact tests were analyzed. These analyses revealed that the absorbed impact energy of the specimens with asymmetric laminated angles was greater than that of the specimens with symmetric laminated angles. In addition, the asymmetry ply absorbed more impact energy than the symmetric ply. Finally, the absorbed impact energy was inversely proportional to the thermal characteristics of the specimens.

Energy acquisition due to the increase of oil price is one of the most important issues and policy for most countries. Various tankers have been built in the world and sent to the trade market. It is necessary to build the port infrastructure and facilities to give them proper services such as mooring, packing, storing, and transshipment, etc. However, the domestic guidelines or standards for design and construction for the dolphin berth among these facilities are out of date and do not meet the recent trend of tanker types. Therefore, it requires amendment on the guidelines or standards. In this study, a detailed analysis of the tanker fleet, covering 8,000 ships under operation and order to build, is made to estimate the proper PBL(Parallel Body Length) of each tanker class. After discussion and comparison on the dolphin berth design and construction codes of various countries, those are the leading countries of tanker operation and management, suggestion was made to amend on the design code. The referred codes are of Korea, Japan, UK, USA, and Canada. The analysis of tanker fleet shows the PBL as 0.45L under the normal ballast condition. In order to verify the deduced amendment on the domestic design code for dolphin berth, it was selected one of the domestic dolphin berth, located at the Yeosu oil terminal, which is almost completed to construct. The design criteria and expected tankers to moor in that terminal were analyzed and the appropriateness and countermeasure for deficiency were summarized.