• 한국멀티미디어학회논문지
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• 제12권4호
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• pp.483-491
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• 2009

본 논문에서는 서브블룩 부분 계수 적응 제거를 통한 고속 움직임 추정 알고리즘을 제안한다. 제안한 방법은 초기 절대 오차의 합과 현재까지의 최소 SAD의 관계를 이용하여 각 서브블록별 임계치를 적응적으로 예측하며, 예측된 엄계치를 이용하여 기존의 부분 에러 제거(PDE: partial distortion elimination) 방법에서의 불필요한 계산을 효율적으로 줄인다.제안한 알고리즘은 기존의 전역 탐색 알고리즘과 비교하여 예측 화질의 저하 없이 기존의 PDE 알고리즘에 비해 60% 이상의 계산량을 줄였으며, 기존의 다른 고속 움직임 예측 알고리즘에 적용하여 불필요한 계산량을 효율적으로 줄일 수 있음올 보인다. 제안한 알고리즘은 MPEG-2 및 MPEG-4 AVC를 이용하는 실시간 비디오 압축 응용분야에 유용하게 사용될 수 있을 것이다.

• Biomolecules & Therapeutics
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• 제10권2호
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• pp.117-123
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• 2002

CJ-10882, (E)-[(3-Cyclopentyloxy-4-methoxyphenyl)methylene]hydrazine-carboxamide, is a newly developed type IV phosphodiesterase isozyme (PDE IV) inhibitor. To investigate the subacute toxic effects of CJ-10882, it was administered to both male and female dogs at 0, 25, 50, 100 or 200 mg/kg/day orally for up to 2 weeks. During the test period, clinical signs, mortality, body weight, food consumption, ophthalmoscopy, urinalysis, hematology, serum biochemistry, gross finding, organ weight, and histopathology were evacuated. Several clinical signs were observed in treated dogs at above 25 mg/kg, including salivation and vomiting. A reduction in the body weight was observed in both sexes at above 50 mg/kg. There were no treatment-related effects on mortality, ophthalmoscopy, urinalysis, hematology, sect biochemistry, necropsy findings, and histopathology in any treatment group. The results of this study demonstrate that CJ-10882, a selective Inhibitor of the type IV class of PDE, may cause effects on gastrointestinal tract and salivary glands. Therefore, these organs should be closely examined in studies with other PDE IV inhibitors.

• Computers and Concrete
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• 제15권1호
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• pp.127-140
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• 2015

The process of chloride ingress in saturated concrete was presented by a previous study that used a mathematical model for the same as that concrete. This model is to be studied chloride ion diffusion which is considered as a chemical phenomenon and is to be represented the chloride diffusion process to be a nonlinear partial differential equation (PDE). In this paper, this nonlinear PDE is solved by the Kirchhoff transformation to render into a linear PDE. This linear PDE associated with initial and boundary conditions is also solved by the Laplace transformation to obtain an analytical solution. To verify the serviceability and reliability of this proposed method, the practical application should be supplied. The input parameters were cited from the previous study. The free chloride concentration profiles obtained by the analytical solution of mathematical model for saturated concretes after 24 and 120 hrs of exposure were compared with the previous study. The predicted results obtained from proposed method have a tendency with experimental results obtained by the previous study and trend toward numerical results approximated by finite difference technique.

• 한국수학사학회지
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• 제29권6호
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• pp.353-363
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• 2016

In mathematical population ecology which is an academic field that studies how populations of biological species change as times flows at specific locations in their habitats, PDE models have been studied in many aspects and found to have different properties from the classical ODE models. And different approaches to PDE type models in mathematical biology are still being tried currently. This article investigate various forms to express diffusion effects and review the history of PDE models involving diffusion terms in mathematical ecology. Semi-linear systems representing the spatial movements of each individual as random simple diffusion and quasi-linear systems describing more complex diffusions reflecting interspecific interactions are studied. Also it introduce a few of important problems to be solved in this field.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 D
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• pp.2568-2570
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• 2004

CEMTool is a command style design and analyzing package for scientific and technological algorithm and a matrix based computation language. In this paper, we present new FEM (Finite Element Method) package in CEMTool environment. In contrast to the existing MATLAB PDE Toolbox, our proposed FEM package can deal with the combination of the reserved words. Also, we can control the mesh in a very effective way With the introduction of new mesh generation algorithm and NDM (Hosted Dissection Method), our FEM package can guarantee the shorter computational time than MATLAB PDE Toolbox. In addition, using the advanced electromagnetics library of CEMTool FEM package, we can analyze the practical problems such as the motor field analysis. Consequently, with our new FEM package, we can overcome some disadvantages of the existing MATLAB PDE Toolbox.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2009년도 IWAIT
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• pp.529-534
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• 2009

This paper reports a non-photorealistic rendering method for creating stream pattern from an input image. Our method extracts potential stream pattern in the given image. The proposed approach uses a shock filter based on a partial difference equation(PDE) which is implemented by applying a selective dilation and erosion processes. However, unlike the traditional first order solution to the PDE, we employ a second order scheme and compensate for the undesired diffusive effects caused by a viscosity form. The selection of dilation or erosion for a pixel is based on an edge detector computed from a structure tensor. By adding noises on to the input image, our method also can generate stream pattern even if there is less texture in some area. The experimental results show that the stream pattern is extracted very well.

• 한국연소학회:학술대회논문집
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• 대한연소학회 2003년도 제27회 KOSCO SYMPOSIUM 논문집
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• pp.153-157
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• 2003

Supersonic and hypersonic aircrafts must pass wide range of speed to reach high speed region. But for existing engines the most efficient operating speed ranges are decided according to their flying speed, so an engine which mixes several engines like TRJ (Turbo Ramjet) and ARJ (Air Turbo Ramjet) has been planed. This mixed type engine has inefficiency that more than two engines must be installed simultaneously, but the pulse detonation engine (PDE) that uses detonation wave has a strong point that it can operate in all speed range with single engine. This paper deals with the simulation of the pulse detonation engine which uses hydrogen peroxide $(H_2O_2)$ mono propellant. Hydrogen peroxide is low-cost propellant, and it is reacted without oxidizer. Comparison between $H_2-O_2$ mixture with $H_2O_2$ mono propellant about thrust, pressure, temperature and velocity shows that $H_2O_2$ is a very useful propellant.

• 생약학회지
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• 제43권2호
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• pp.184-191
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• 2012

The aim of this study was to explore the potent phosphodiesterase type 5 (PDE %) inhibitor from various herbal medicines for erectile dysfunctions. In this study, 61 herbal medicines, which were extracted with ethanol, have been investigated with PDE 5 assay using enzyme inhibitory activity on 22 species of herbal medicines. Of these, 5 species of herbal medicines, Cnidium monieri, Cuscuta chinensis, Epimedium koreanum, Morinda officinalis, and Tribulus terrestris were exhibited stronger inhibitory effect against phosphodiesterase 5 (PDE 5) among 61 species; Cnidium monieri ($IC_{50}=33.7{\mu}g/ml$), Cuscuta chinensis ($IC_{50}=65.7{\mu}g/ml$), Epimedium koreanum ($IC_{50}=90.3{\mu}g/ml$), Morinda officinalis ($IC_{50}=48.7{\mu}g/ml$) and Tribulus terrestris ($IC_{50}=32.5{\mu}g/ml$).

• Archives of Pharmacal Research
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• 제27권12호
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• pp.1258-1262
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• 2004

Phosphodiesterase (PDE) 4 is an enzyme that degrades intracellular cAMP. In the present study, the effect of rolipram, a specific phosphodiesterase (PDE) 4 inhibitor, on osteoclast formation was investigated. Rolipram induced osteoclast formation in cocultures of mouse bone marrow cells and calvarial osteoblasts. This activity was not observed in the absence of calvarial osteoblasts, suggesting that calvarial osteoblasts are likely target cells of rolipram. Osteoclast formation by rolipram was completely blocked by the addition of osteoprotegerin (OPG), a soluble decoy receptor for the osteoclast differentiation factor, TNF-related activation-induced cytokine (TRANCE, identical to RANKL, ODF, and OPGL). Northern blot analysis revealed the effect of rolipram to be associated with the increased expression of TRANCE mRNA in mouse calvarial osteoblasts. Collectively, these data indicate that PDE4 inhibitor up-regulates the TRANCE mRNA expression in osteoblasts, which in turn controls osteoclast formation.

• 약학회지
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• 제49권1호
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• pp.109-113
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• 2005

In the present study treatment of IBMX, a phosphodiesterase (PDE) inhibitor, alone induced osteoclast formation in co-cultures of mouse bone marrow cells and calvarial osteoblasts. However, treatment of IBMX in combination with prostaglandin $E_2\;(PGE_2)$ inhibited osteoclast formation in a dose-dependent manner. Among various isozyme-specific PDE inhibitors, a PDE4 specific inhibitor, rolipram, showed similar effects as IBMX on osteoclast formation. To address the involvement of cyclic adenosine monophosphate (cAMP) in osteoclast formation, cAMP concentration in calvarial osteoblasts was investigated. When calvarial osteoblasts were co-cultured with IBMX alone or in combination with $PGE_2$, the patterns of cAMP concentration in calvarial osteoblasts were differ each other suggesting that cAMP in calvarial osteoblasts subtly regulates osteoclast formation.