• 대한수학회보
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• 제54권4호
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• pp.1221-1228
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• 2017

We consider weighted Hardy spaces on bidisk ${\mathbb{D}}^2$ which generalize the weighted Bergman spaces $A^2_{\alpha}({\mathbb{D}}^2)$. Let z, w be coordinate functions and $T_{{\bar{z}}^N}_w$ Toeplitz operator with symbol $_{{\bar{z}}^N}_w$. In this paper, we study the reducing subspaces of $T_{{\bar{z}}^N}_w$ on the weighted Hardy spaces.

• 한국작물학회지
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• 제39권2호
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• pp.139-145
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• 1994

보리(Hordeum vulgare L.) 품종인 백동을 공시하여 Polyethylene glycol로 배지의 수분 potential을 0, -5bar, -10bar, -15bar, -200bar로 조절하여 종자를 침지후 초기의 발아율, 발아속도, 호흡계수, $\beta$-amylase 활성과 환원당, 종자의 생건비 등을 조사하여 발아에 미치는 수분부족의 영향을 시험한 결과를 요약하면 다음과 같다. 1. 수분이 부족할 수록 발아율의 감소 및 발아속도 지연이 극심하였다. 2. 호흡계수(Respiratory quotient :R.Q.)는 배지의 수분 potential이 낮아짐에 따라 점차 증가한다. 3. $\beta$-amylase의 활성은 배지의 수분potential이 높아짐에 따라 높아지고 환원당량도 많아지는데 이는 종실이 충분한 수분을 흡수하지 못한 상태에서 흡수된 수분중 상당량이 세포의 구조적 수분이나 구조유지에 사용되어지기 때문이다. 4. 흡습종자의 생건비는 배지의 수분potential이 높아짐에 따라 낮아지나 심한 수분부족에 처하게 되면 도리어 상승한다. 5. 배지의 수분 potential이 -10bar이상으로 유지되어야 종자가 정상적인 발아를 하며 초기생육도 왕성하게 유지될 수 있겠다.

• 한국구조물진단유지관리공학회 논문집
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• 제10권5호
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• pp.129-138
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• 2006

철근 선조립형 복합 데크플레이트는 거푸집 작업을 없앨 수 있기 때문에 건설현장에서의 발전을 가져왔다. 복합데크 시스템의 해석에는 2D해석법과 3D해석법이 있다. 지금까지 2D해석법을 사용하였으나, 선경축소에 따른 비렌딜 거동을 보다 정확히 표현할 수 있는 3D 해석법의 사용이 요구되어진다. 본 연구에서는 하부근의 선경축소, 아연도 강판의 유무, 경간, 슬래브 두께 등을 변수로 8개의 실험체를 제작하여 거동을 파악하였고, 2D해석법 및 3D해석법을 사용하여 결과를 비교 분석하였다. 2D해석법은 D10의 하부근을 사용하는 경우에만 적용하는 것이 타당하고, 비렌딜 거동을 포함한 상세한 거동을 표현하기 위해서는 3D해석법을 사용하는 것이 타당하다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2006년도 추계 학술논문 발표대회 논문집
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• pp.83-86
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• 2006

This study investigates engineering properties of concrete using recycled coarse aggregated manufactured by bar-crusher. Test showed that Bar-crusher(S) had more effective results at fresh state than cone-crusher(C) and impact-crusher(I). In case of specimens manufactured by S, increase of spindle velocity, incorporating ratio of recycled aggregate and maximum size of aggregate inclined fluidity. As for the hardened concrete, compressive strength of specimens by C or I exhibited lower value than that of S. In addition, specimens using recycled aggregate manufactured by 400rpm and 500rpm of spindle velocity showed less than 10% reduction rate of strength, which is not significant reducing value. It is found that 500rpm of the spindle velocity had the best strength performance, while 600rpm was the worst. Strength value of specimens decreased as incorporating ratio of recycled aggregate inclined, but the strength value of most specimens exhibited less than 10% of reducing rate, assuming favorable result, only at less than 25% incorporating ratio of recycled aggregate.

• 대한치과의사협회지
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• 제54권1호
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• pp.39-48
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• 2016

SFI-bar is prefabricated bar system and can be assembled at chairside without soldering or welding, thus reducing bone loss, costs and time. A 53-year-old male patient, who had severely absorbed mandible, hoped to wear a stable mandiblular denture. Four implants were placed in the extraction site of canine and 1st molar. Early loaded temporary denture with solitary type attachment was delivered 3 weeks after surgery. 3 month later, SFI-bar was connected and adjusted at chairside. Then, implant overdenture using SFI-bar was delivered. This case report showed that a satisfactory clinical result was achieved by 4-implant-supported overdenture using the SFI-Bar system in a mandibular edentulous patient.

• 한국건축시공학회지
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• 제10권4호
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• pp.123-132
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• 2010

Rebar work accounts for approximately 30% of the total construction costs for rebars and concrete. Recently, the high rising prices of rebars have become one of the principle factors of rising construction costs. Therefore, construction companies are putting much effort into loss reduction of rebars. Consequently, in this study, we wished to present loss reduction methods of rebars before the preparation of the placing drawings. To devise such methods, we collected previous case studies and analyzed methods that were applied for loss reduction. As a result of the analysis, we were able to find the following methods for loss reduction of rebars: method of reducing the number of splices at the mat foundation, method of reducing splice length at the internal columns or walls of the underground parking lot, method of reducing cap-ties of internal beams of basement floors excluding perimeter beams, and method of reducing anchorage length at the internal column or wall of the underground parking lot. Based on those analysis results, we presented our own loss reduction methods of rebars. Applying our methods resulted in considerable loss reduction.

• 대한조선학회논문집
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• 제46권5호
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• pp.460-470
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• 2009

In recent practice a half round prismatic bar has fillet welded or formed through foundry work along the centerline on rear concave surface of the horn to mitigate gap flow between fixed and movable part of the rudder system. When the gap clearance has been blocked with this practice, numerical simulations indicate that the practices are not only effective in reducing the gap flow but also in mitigating the cavitation. The blocking effects are remarkably improved when a pair of blocking bar is bisymmetrically attached with respect to centerline on the opposite convex surface of the movable part. The blocking bar could be placed on the exposed surface under maximum rudder angle. This implies that the blocking bar could be easily adopted not only in a design stage but also in a maintenance stage for mitigating rudder cavitation. In addition, the numerical simulations imply that more improvements could be anticipated through the selection of section shape of prismatic bar for gap flow blocking.

• 한국기계가공학회지
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• 제15권1호
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• pp.34-41
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• 2016

Bar camber is a phenomenon in which a material with a deformation gradient across its width is bent in the right or left direction in the roll gap. This paper proposes a dynamic setup approach for a side guide for reducing bar camber. A bar tracking scheme using a rotary encoder was adopted to fix an operation point for the side guide. The guiding pressure was utilized for measuring the actual width of the bar with camber. Based on the accurate position and width of the bar, the side guide was dynamically set and operated at the actual roughing train in a hot strip rolling mill. The amount of camber was reduced notably when the dynamic setup scheme was installed in the side guide. 78% of the bars tested had a camber in the range of ${\pm}20mm$, which was an improvement of 27% in terms of production yield.

• 대한수학회보
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• 제52권5호
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• pp.1649-1660
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• 2015

In this paper, we completely characterize the nontrivial reducing subspaces of the Toeplitz operator $T{_{z{^N_1{\bar{z}}^M_2}}$ on the Bergman space $A^2(\mathbb{D}^2)$, where N and M are positive integers.

• Journal of Advanced Marine Engineering and Technology
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• 제36권4호
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• pp.467-475
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• 2012

이 논문에서는 비틈 봉을 기반으로 한 중력보상기가 적용된 새로운 외력증강기를 이용하여 인체 다리관절에 작용하는 부하를 경감시키는 방법에 대해 제안한다. 비틈 봉 특성을 추정하고 측정하기 위하여 설계와 구조 해석을 행하였다. 설계와 구조해석을 바탕으로 매우 경량이고 소형인 새로운 외력증강기를 개발하였다. 구조해석은 외력증강기를 매우 경량으로 하기위해 최적두께의 링크에 대한 FEM해석을 행하였다.