• The KSFM Journal of Fluid Machinery
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• v.17 no.3
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• pp.65-70
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• 2014

The effectiveness of a perforated plate installed additionally at butterfly valve to reduce cavitation which can cause vibration, noise, erosion, and flow path blockage has been investigated using CFD. Rayleigh-Plesset equation was applied to simulate cavitation phenomena. 3D flow simulations have been performed for 6 cases to consider the occurrence of cavitation at the downstream of the valve. From the present results, the perforated plate was thought to be very effective to suppress the cavitation inside of the pipe.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.569-572
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• 2002

In the present study, flow simulations of a solution pump fer an absorption chiller are performed. The results are compared to the experimental data. Since the cavitation is more likely to occur in a solution pump due to Its operation under vacuum condition, and the cavitation was not considered in the present computations, the computed and experimental results show large discrepancies. For more accurate performance prediction of a solution pump, a cavitation model is required in the flow simulation. Flows through an inducer are also studied to see the effect of design parameters on performance characteristics. It is shown from the results that, if not properly designed, recirculation legion may exist near the hub region of the Inducer, and the suction surface may experience higher pressure than the pressure surface of the inducer, which may deteriorate the performance.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2011.06a
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• pp.376-378
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• 2011

Hamburg is going with the HafenCity Project to create new urban space for city's bustling central district. HafenCity will add an additional 155 hectares to Hamburg's central urban area, increasing its total area by some 40 percent. The new developments in HafenCity will be oriented towards the River Elbe and the great seaport. Its centre will have a close relation to water. They will be used for the construction of a fascinating mix of residential accommodation, offices, cultural and leisure amenities, retail facilities and restaurants set in a framework of an elaborate urban layout. This study is focusing on the purpose of the project goals, the task of the Hamburg authorities and GHS (Gesells chaft f$\ddot{u}$r Hafen und Standortentwicklung) and an urban planning ideas competition (draft masterplan). Regarding of the new trend of the reurbanisation in Europe, the aim of this study will be to find out, in which way Hafencity is trying to develope the new city district as a model for the European inner city of the 21st century.

• Journal of Navigation and Port Research
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• v.35 no.6
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• pp.539-550
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• 2011

Hamburg is going with the HafenCity Project to create a new urban space for the city's bustling central district. HafenCity will add an additional 155 hectares to Hamburg's central urban area, increasing it's total area by some 40 percent. The qualities of the HafenCity are mainly marked through the location at the water, the river Elbe and the historically embossed milieu the Speicherstadt. A tightly mix of residential accommodation, offices, cultural and leisure amenities, retail facilities and restaurants manages diverse identities of quarters in a framework of an elaborate urban layout. This study is focusing on the purpose of the project goals, the task of the Hamburg authorities and GHS (Gesellschaft fur Hafen und Standortentwicklung) and an urban planning ideas competition (draft masterplan). Regarding of the new trend of the reurbanisation in Europe, the aim of this study is to find out, in which way HafenCity is trying to develope the new city district as a model for the European port city of the 21st century.

• Horticultural Science & Technology
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• v.30 no.1
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• pp.1-5
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• 2012

This study was conducted to elucidate the cause of micro-cracking in the exocarp of 'Jinmi' peach (Prunus persica). through the microscopic observation of fruit skin development in 4 varieties such as 'Jinmi', 'Kanoiwa Hakuto', 'Kawanakajima Hakuto', and 'Yumyeong'. Micro-cracking was noted in 59.1% of 'Jinmi', 30.6% of 'Kanoiwa Hakuto', 21.5% 'Kawanakajima Hakuto' and 6.4% of 'Yumyeong', respectively. The development of intercellular spaces, which increased rapidly with the fruit development, was easily observed at 69 days after full bloom. Histological studies revealed that the number of outer epiderm cell layers of 'Jinmi' was smaller than that of the other three cultivars, and thinner than the 'Kawanakajima Hakuto' and 'Yumyeong'. Moreover, 'Jinmi' exhibited smaller and flatter shapes in the sub-epidermal cell layer than those of the 'Kawanakajima Hakuto' and 'Yumyeong' at harvest season. Therefore, these results suggest that micro-cracking of 'Jinmi' fruit skin was due to poor-developed outer epidermis and well-developed intercellular spaces just under exocarp as compared with other varieties.

• Journal of Welding and Joining
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• v.15 no.4
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• pp.36-41
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• 1997

제조업의 공동화 현상 및 3D 작업의 기피 현상 등으로 용접 고기량자의 구인 난 및 신규 용접인력의 감소 현상이 나타나고 있다. 이는 단기적으로는 경량 간이 용접 장치를 1인이 다수대를 운용함으로써 해결 가능하지만 적용 부위가 한정되고 수정 부위가 과다 발생되어 근본적인 해결책이라 보기는 어렵다 따라서 지능형 용접 ROBOT의 적용을 통한 용접기량자의 대체가 요구되어 지고 있다. 반면에 용접 ROBOT에 의한 고효율 및 고품질의 용접을 위해서는 용접재료, 용접기등의 발전도 중요하지만 고기량자에 준하는 최적 용접조건의 선정이 무엇보다도 중요하며 다양한 대상물에 대한 다양한 용접 사양을 만족하기 위해서는 기존 TEST를 통해서 얻어진 최적 용접 조건의 재현만으로는 한계를 가지게 되며 LASER SENSOR 등을 통한 용접부의 GROOVE 형상 혹은 ROOT GAP의 감지와 이에 적합한 용접조건을 REAL TIME으로 결정할 수 있는 용접 정보 처리 시스템이 요구된다. 본 연구에서는 광범위한 용접정보 처리 시스템중 조선분야에 비중이 제일 큰 단층 FILLET 용접부위에 대하여 용접 ROBOT SYSTEM을 적용 할 경우 표준용접 조건 및 용접조건 최적화를 위한 용접전문가 시스템의 연구결과를 소개하고 향후 전망에 대해서 의견을 제시하고자 한다.

• The Science & Technology
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• v.32 no.5 s.360
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• pp.30-31
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• 1999

IMF체제 하의 우리 과학기술계는 기업의 연구비 조달이 어렵게 되어 기술개발을 위한 연구활동이 공동화 현상을 빚고 있다. 국가 기술개발 투자의 80% 이상을 담당해 왔던 민간부문의 투자 감소는 21세기 기술선진국 진입의 꿈을 깨는 가장 큰 장애요소가 되고 있다. 폭넓은 경험과 우수한 인적자원을 갖고 있는 기업들이 앞으로 기술개발에 적극 참여토록 유도하여 민간주도의 기술개발시대를 열어야 하겠다.

• Corrugated packaging logistics
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• s.122
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• pp.46-50
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• 2015

중소기업중앙회 등 33개 경제단체 및 38개 발전 에너지기업은 지난 6월 16일 정부가 최근 발표한 2030년 온실가스 감축 목표에 대한 공동의견서를 발표했습니다. 경제계는 발표문에서 "정부가 본실가스 감축 목표를 과도하게 실정해 우리 기업의 경쟁력이 약해지고 산업공동화 현상을 초래할 수 있다"며 "2030년 온실가스 감축 목표치를 재조정해야 한다"고 주장했습니다. 7 8월 골판지포장물류지에서는 최근 정부가 제시한 2030년 온실가스 감축 목표안과 감축이유에 대해 자세히 살펴보도록 하겠습니다.

• 유체기계공업학회:학술대회논문집
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• 2003.12a
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• pp.353-360
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• 2003

Hydraulic performance and cavitation characteristics of fuel pump in turbo-pump were studied experimentally. The fuel pump has a centrifugal impeller with a separate inducer. In this paper, flow characteristics of inducer and impeller was experimentally investigated separately and together. Especially static pressure distribution of Inducer was examined in non-cavitation and cavitation conditions.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2021.11a
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• pp.148-150
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• 2021

어촌은 바다, 섬, 자연경관, 해양레저, 수산자원 등의 다양한 해양 관광자원을 보유하고 있어 성장 잠재력이 풍부하나, 이를 통해 성장할 수 있는 기본적 인프라 및 콘텐츠가 절대적으로 부족한 실정이다. 또한 수산업 침체와 어촌인구 감소 및 고령화로 어촌 공동화 현상이 심화되고 있으며, 정주환경 저하 등 삶의 질 전반에 걸쳐 낙후된 상태이다. 본 연구에서는 어촌마을의 자원활용과 자원 간의 연계를 촉진시킴과 동시에 정주기능, 생산기능의 활성화를 도모할 수 있는 소득증대 방안을 마련하고자 함