• 한국식품영양과학회지
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• 제31권4호
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• pp.636-641
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• 2002

인공재배한 상황버섯 원료의 영양성분은 탄수화물의 함량이 80.9%로 가장 많았고, Na, K, Ca, Fe의 무기질 4종도 비교적 풍부하게 함유되어 있었으나 비타민 B$_1$, B$_2$, C와 같은 수용성비타민은 검출되지 않았다. 가장 바람직한 추출조건은 5% 농도의 원료를 10$0^{\circ}C$의 온도에서 3시간 이내에 추출하는 것으로 나타났다. 추출물의 청정화를 위해서 depth filter pad를 이용한 여과법, 원심분리법 및 여과조제 첨가법 등을 적용한 결과 원심분리와depth filter pad를 이용했을 때 가장 우수한 청정효과를 나타내었고, 7주간 항온저장실험으로 탁도를 비교한 결과에서도 청정도의 변화가 거의 없었다. 결론적으로 상황버섯 추출물은 6,000 rpm이상에서의 원심분리나 8$\mu\textrm{m}$ 이하의 pore size를 지닌 filter system을 이용할 때 청정도를 가장 효과적으로 유지할 수 있었다

• 방송공학회논문지
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• 제17권4호
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• pp.565-571
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• 2012

깊이 정보를 획득하고 전송하는 과정에서 물리적 잡음 및 부호화 손실로 인하여 깊이맵의 품질이 저하된다. 본 논문은 깊이맵 품질을 향상시키기 위해 공동 거리 변환에 기반한 결합 양측 필터(joint bilateral filter)를 제안한다. 제안하는 방법은 깊이맵의 거리 변환값과 색상 영상의 거리 변환값에 따라 잡음 제거에 필요한 색상 정보량을 결정한다. 그 결과 제안하는 필터는 깊이맵 잡음을 효과적으로 제거하면서 결합 양측 필터의 시각적 왜곡 현상을 최소화한다. 컴퓨터 실험을 통해 제안하는 방법이 기존의 방법보다 잡음 제거와 시각적 왜곡 억제 관점에서 성능이 좋아짐을 확인했다.

• 한국물환경학회지
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• 제32권6호
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• pp.537-545
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• 2016

In order to cope with the new and strict government regulations for turbid water discharge from construction sites, this study tested whether synthetic fiber filters can replace conventional best management practices. The filter efficiency was about 10 to 60% with a varying filter depth of 5 to 15cm, presuming extreme storm flow conditions to be in the range of 800 to 1500m/day of filtration rates. Fiber filter acts exactly like a granular filter, i.e. the separation efficiency is directly and inversely proportional to filter depth and rate, respectively. Based on the operational data, we suggested the Log-Log design relationship, which can be used to determine the filter depth and area. Compared to the widely used gravel filter which treats the turbid water at the construction site, about 20% higher efficiency was obtained under similar operating conditions. Cleaning the filter through a simple hand-washing method at the time of break-through, achieved about 90% soil recovery.

• 반도체디스플레이기술학회지
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• 제9권3호
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• pp.65-69
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• 2010

The stereoscopic vision system is the algorithm to obtain the depth of target object of stereo vision image. This paper presents an efficient disparity matching method using nagao filter, octree color quantization and dynamic programming algorithm. we describe methods for performing color quantization on full color RGB images, using an octree data structure. This method has the advantage of saving a lot of data. We propose a preprocessing stereo matching method based on Nagao-filter algorithm using color information. using the nagao filter, we could obtain effective depth map and using the octree color quantization, we could reduce the time of computation.

• 한국물환경학회지
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• 제32권1호
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• pp.36-45
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• 2016

강우유출수 오염물 제거를 위한 침투시설에서 모래필터가 널리 적용된다. 공극폐색, 즉 필터 여재에 부유물이 침전되면 침투능이 저하되어 침투시설의 기능과 수명이 단축된다. 침투시설의 효과적인 설계 및 유지관리를 위해 모래필터 내의 물리적, 화학적, 생물학적 폐색 특성을 알아야 한다. 이 논문에서는 여재 깊이 변화에 따른 모래필터의 물리적 폐색 특성변화를 검토하였다. 연직방향, 변수위 침투조건에서 시행한 실험실 컬럼 침투실험으로부터 이들 특성변화를 관찰하였다. 실험결과, 폐색현상의 결과로서 필터의 여재 깊이가 증가할수록 부유물 제거효율이 증가하지만, 필터의 성능유지 기간은 감소하는 현상을 보였다. 모든 여재 깊이 조건에서 여재 깊이의 상부 15%에서 100~250 μm의 부유물이 침전되면서 폐색현상이 발현하는 조기폐색이 발생했다. 결과에 근거하여 침투시설의 첫번째 유지관리 시침투능 확보를 위해 여재깊이의 상부 15%를 긁어내는 방법을 제안할 수 있었다.

• 한국대기환경학회지
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• 제20권3호
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• pp.361-369
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• 2004

A metal fiber bed has seldom been applied to the practical filtration process despite its excellent mechanical and chemical stability. The filter-bed used in this work was highly porous with open structure, of which apparent porosity was 80 ∼ 90%. Although pressure loss across the filter-bed was very low, separation efficiency was found to be quite high. This paper focuses on the basic filtration mechanisms of a metal filter-bed and a thin ceramic filter from fly ash for reference. The experimental parameters were face velocity, dust loading and porosity of filter-bed. Pressure drop increased with increasing face velocity and dust feeding load for both filters. It also showed that dust particles deposited in the deep flow path, finally resulting in clogging the pore channels. It thereby indicates that the dominating mechanism of the metal filter-bed would be depth filtration. Meanwhile, the thin fly ash composite filters trapped the aerated dust mainly on the surface of the filter medium, so that the instantaneously formed dust layer might cause a steep increase of pressure drop across the filtration system.

• 전기전자학회논문지
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• 제24권2호
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• pp.507-513
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• 2020

중간값 필터는 n×m 크기의 이미지와 반경 r이 주어지면 이미지의 모든 픽셀에 대해 반경 r에 속하는 픽셀들의 중간값으로 변환하는 것으로, 이미지 처리가 필요한 다양한 분야에서 활용되고 있다. 픽셀의 정보가 8비트인 경우에는 O(nm) 시간 알고리즘이 존재하나 16비트 이상에는 적용이 어렵고 대신 Gil과 Werman의 O(nmlog²r) 시간 알고리즘이 존재한다. 본 논문에서는 16비트 깊이 이상의 정보를 갖는 이미지에 대해서도 효율적으로 동작하는 중간값 필터 알고리즘을 제안한다. 시간 복잡도는 O(nmlog²r)로 Gil과 Werman의 알고리즘과 동일하지만 엄밀한 분석과 실험을 통해 2배 이상 향상됨을 보인다.

• ETRI Journal
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• 제33권5호
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• pp.695-703
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• 2011

The number of adders and critical paths in a multiplier block of a multiple constant multiplication based implementation of a finite impulse response (FIR) filter can be minimized through common subexpression elimination (CSE) techniques. A two-bit common subexpression (CS) can be located recursively in a noncanonic sign digit (CSD) representation of the filter coefficients. An efficient algorithm is presented in this paper to improve the elimination of a CS from the multiplier block of an FIR filter so that it can be realized with fewer adders and low logical depth as compared to the existing CSE methods in the literature. Vinod and others claimed the highest reduction in the number of logical operators (LOs) without increasing the logic depth (LD) requirement. Using the design examples given by Vinod and others, we compare the average reduction in LOs and LDs achieved by our algorithm. Our algorithm shows average LO improvements of 30.8%, 5.5%, and 22.5% with a comparative LD requirement over that of Vinod and others for three design examples. Improvement increases as the filter order increases, and for the highest filter order and lowest coefficient width, the LO improvements are 70.3%, 75.3%, and 72.2% for the three design examples.

• ETRI Journal
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• 제26권6호
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• pp.545-554
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• 2004

In this paper, we propose an efficient design method for area optimization in a digital filter. The conventional methods to reduce the number of adders in a filter have the problem of a long critical path delay caused by the deep logic depth of the filter due to adder sharing. Furthermore, there is such a disadvantage that they use the transposed direct form (TDF) filter which needs more registers than those of the direct form (DF) filter. In this paper, we present a hybrid structure of a TDF and DF based on the flattened coefficients method so that it can reduce the number of flip-flops and full-adders without additional critical path delay. We also propose a resource sharing method and sharing-pattern searching algorithm to reduce the number of adders without deepening the logic depth. Simulation results show that the proposed structure can save the number of adders and registers by 22 and 26%, respectively, compared to the best one used in the past.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.3122-3122
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• 2001

Documented quality control plays a vital role I the production of technical “Depth filter” sheets used in industries such as Beverage and pharmaceutical. Depth filter sheets which can be up to several millimeters thick are stacker in plate and frame filter systems. They are the core of stainless steel filter systems which can be up to several meters high. FT-NIR Spectroscopy has many potential applications in the whole production line of filter sheets. Raw materials such as different types of cellulose pads, white powdery fillers (e.g. Kieelgur, Perlite) or liquid chemicals such as wet-strength agents we, with the help of NIR, easy to identify. NIR can also determine physical parameters such as particle size, essential for the filtration behavior. FT-NIR can be used for the quality parameters of the final product. Moisture and permeability can be determined, and with the help of the speed of this NIR method it is possible to correct possible faults quickly in the production process. Waste production can be minimized which is good for both the product profitability and the environment. Further tests have shown that it is also possible to use NIR on-line in the production area, to check the concentrations and the homogeneity of the paper suspension consisting of cellulose fibres, fillers and additives.