• Journal of Korean Society of Environmental Engineers
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• v.27 no.7
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• pp.726-731
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• 2005

Sedimentation is treated as the most important unit process in waterworks, and plays great role on turbidity removal efficiency. Rectangle sedimentation basin is the most widely accepted sedimentation process. But it has some problems with short-circuit flow and density flow caused by temperature and influent turbidity variation. To solve these problems, installation of rectification wall was suggested, but not generally fully accepted in field. Because hole of rectification wall cause jet flow. In this research, use of moving baffle was investigated. Moving baffle was designed to induce uniform velocity at every section of water flow. The baffle walls was made from soft fiber materials. The baffle walls with flow of sedimentation basin moves at same speed. It is like that it controls density flow and short-circuit flow and induce uniform velocity at every section of water flow in sedimentation basin. When moving baffle was operated retention time of sedimentation basin was extended to 1 hours. When it talked again and the effluent time of highest concentration of the chlorine ion from 100 minutes was extended to 160 minutes. Turbidity removal efficiency was tested with different operation modes(continuous and batch) with influent turbidity and retention time. It was revealed that turbidity removal efficiency carl be improved up to 36%(continuous mode) and 58%(batch mode) respectively. Consequently if moving baffle introduces in Rectangle sedimentation basin, it forecasts that the turbidity improvement above 30% will be possible.

• Korean journal of applied entomology
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• v.35 no.2
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• pp.119-125
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• 1996

Temperature-dependent development study for overwintered eggs of Pseudococcus comstocki (Kuwana) wasconducted to develop a forecasting model for egg hatch date. Hatch times of overwintered eggs were comparedat five constant temperatures (10, 15, 20, 25, 27$^{\circ}$C) and different collection dates. A nonlinear, four-parameterdevelopmental model with high temperature inhibition accurately described (R2=0.9948) mean developmentalrates of all temperatures. Variation in developmental times was modeled(~~=0.972w9)it h a cumulative Weibullfunction. Least-squares linear regression (rate=O.O06358[Temp.]-0.07566)d escribed development in the linearregion (15-25$^{\circ}$C) of the development curve. The low development threshold temperature was estimated 11.9"Cand 154.14 degree-days were required for complete development. The linear degree-day model (thermal summation)and rate summation model (Wagner et al. 1985) were validated using field phenology data. In degreedaymodels, mean-minus-base method, sine wave method, and rectangle method were used in estimation of dailythermal units. Mean-minus-base method was 18 to 28d late, sine wave method was 11 to 14d late, rectanglemethod was 3 to 5d late, and rate summation model was 2 to 3d late in predicting 50% hatch of overwinteredeggs. hatch of overwintered eggs.

• Korean Journal of Heritage: History & Science
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• v.45 no.2
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• pp.72-99
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• 2012

Cheomseongdae, Korea's so-called "star-gazing tower" located in the former Silla Dynasty capital of Gyeongju, is generally believed to have maintained its original shape since its construction in 647. The stone structure was closely examined and measured by Gyeongju National Museum in 1962 and reexamined by Korean National Research Institute of Cultural Heritage in 2009. This research noted the following structural anomalies of Cheomseongdae. A corner of the top rectangle layer was broken diagonally in a form that can never be attributed to a natural cause. The four metal clamps under the top rectangle layer had been missing. Four grooves, with unknown usage, exist on the sides of the long rectangular stones projected out of the circular body at the second and third circular layers from the top. On the second circular layer from the top, there are three flat stones, less than a half as tall as their surrounding stones. The average height of the third circular layer from the top is only 23.5 cm, while the overall average of the entire 27 circular layers is 29.9cm. This research postulates that all these anomalies are due to prior destructions and improper restorations of the structure. The first destruction and restoration of Cheomsengdae was likely to have occurred before the mid 15th century. The damages might include a pavilion on the top of the structure and a stone with the name of the structure carved in. The Mongolian invasion in the 13th century was a most likely cause. After the restoration, the structure suffered at least another attack. The damages on the top layer and the missing iron clamps were due to the later attack. The grooves and flat stones were to house holding device that affixed certain objects to the outer surface of the circular body. The metal or stone objects might have faced upward at the four corners of Chemseongdae, bridging the gaps between the rectangle layers and circular layers. The current Chemseongdae lost at least the four affixed objects, four holding devices, and one flat stone.

• Journal of the Korean Mathematical Society
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• v.32 no.3
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• pp.461-470
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• 1995

In this paper a capacitance matrix method is developed for the Poisson equation on a rectangle $$ (1-1) Lu \equiv -(u_{xx} + u_{yy} = f, (x, y) \in \Omega \equiv (0, 1) \times (0, 1) $$ with the homogeneous Dirichlet boundary condition $$ (1-2) u = 0, (x, y) \in \partial\Omega $$ where $\partial\Omega$ is the boundary of the region $\Omega$.

• Journal of the Korean Ceramic Society
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• v.39 no.10
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• pp.907-911
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• 2002

Using the two-dimensional Wulff plot, the equilibrium shape of a sapphire crystal was investigated as a function of surface energy anisotropy. Depending on the relative values of surface energy for various facet planes, the projected shape of equilibrium sapphire was determined to be rectangle, parallelogram, hexagon or octagon. The results are compared with the experimentally observed shapes of internal cavities of submicron range in sapphire single crystals.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.03b
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• pp.583-590
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• 2000

The installation of vertical drains by using a mandrel causes significant disturbance of the subsoil. Thus a smear zone may be developed with reduced permeability and increased compressibility. In this paper the extent of smear zone developing ground disturbance with the installation of mandrels are analysed by field smear zone test. The extent and the consolidation characteristics of smear zones around the mandrels is compared with the shape, the size of mandrel and penetration speed and is evaluated from the field smear test results. (circular, sqare, rectangle and oval type)

• Proceedings of the Korean Information Science Society Conference
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• 2003.04c
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• pp.232-234
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• 2003

차량 번호판 인식 시스템은 차량 보급의 대중화와 그에 따라 발생되는 여러문제의 해결차원에서 활발하게 연구 개발되고 있는 분야이다. 본 논문에서는 휴대용 입력 장치로부터 획득한 차량 번호판 영상에서 차량 번호판이 가지는 특성을 이용하여 번호판을 추출한 후, 차량 번호판의 특성을 이용하여 개별 문자 영역들의 MBR(Minimum Boundary Rectangle)을 추출한다. 그리고. 불변 모멘트의 특징을 이용하여 기존의 템플릿 매칭 방식 보다 연산시간이 매우 빠르고 입력 영상내의 번호판 크기에 제약이 적온 장점을 가진 보다 향상된 차량 번호판 인식 시스템을 제안한다.

• Proceedings of the Korea Multimedia Society Conference
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• 2001.06a
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• pp.212-215
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• 2001

본 논문에서는 평면 형상에 대한 새로운 계층적 표현 방법을 소개하였다. 제안한 방법에서는 근사화 과정의 근사화 오차(approximation error)를 근사화 순서와 정도를 결정하는 중요한 척도로 활용하였으며, 제안한 오차 조절 알고리즘을 통해 보다 자연스러운 근사화 표현이 가능하도록 하였다. 그리고 최소 경계 사각형(MBR: Minimum Bounding Rectangle)을 단순 확장한 최소 경계 팔각형(MBO: Minimum Bounding Octangle)을 지역화에 응용하였으며, 이는 다른 지역화 방법들과 비교하였을 때 상대적으로 더 효율적인 방법임을 확인할 수 있었다.

• Journal of the Korean Operations Research and Management Science Society
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• v.14 no.1
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• pp.119-130
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• 1989

This paper presents average travel time models automated warehousing system where the stacker crane transports only one pallet at a time with the tchebychev travel, I/O point is located at the cornor of the rack, and items are stored by the class-based storage assignment rule. In this study, the racks are treated as the continuous rectangle in time and a statistical approach was used to develop the models. In order to test the proposed models, average travel times determined by the models are compared with the true values for various rack shapes.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2004.10a
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• pp.564-567
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• 2004

In this thesis, a method is proposed to extract the car plate at the rear side of vehicle using blobs. We first extract the blobs in the input images using intensity variations and calculate the minimum horde. rectangle (MBR) of each blobs. It is followed that we select groups of blobs having similar width, centroid. And then, we try to detect the border lines of car plate and verify whether the area is a car plate or not using NN.