• Title/Summary/Keyword: P-y models

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Use of water retention curves predicted from particle-size distribution data for simulation of transport of Benzo[a]pyrene in soil

  • Cho Young-A;Hwang Sang-Il;Jang Yong-Chul;Lee Dong-Soo
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2006.04a
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    • pp.216-219
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    • 2006
  • Water retention curve (WRC), one of soil hydraulic properties, is often approximated by property-transfer models (PTMs). Using the PTMs, we can estimate the WRCs from other physical properties such as particle-size distribution (PSD). The objective of this work was to investigate the performance of two PTMs with different origins for numerical simulations on transport of Benzo[a]pyrene in a soil. To do this, we chose both PTMs with different origins, i.e., (1) the lognormal distribution model (L anti NL models), and (2) the modified $Kov\'{a}cs$ model (MK model). The MK model showed tile worse performance in estimation of the WRCs. When transport of B[a]P was simulated, the MK model predicted to move farther than the L and NL models did, indicating that transport of B[a]P in a soil can be greatly influenced by the choice of PTMs.

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Effects of aerobic exercise on antioxidants in rat models with cardiomyopathy

  • Kim, Eun-Jung;Hwang, Sujin
    • Physical Therapy Rehabilitation Science
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    • v.4 no.1
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    • pp.17-21
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    • 2015
  • Objective: In this study, we aimed to test the hypothesis that aerobic exercise might exert its cardio-protective effect by preventing oxidative stress and improving cardiac function in rat models with doxorubicin-induced cardiomyopathy. Design: Randomized controlled trial. Methods: We randomly divided experimental rats into four groups: the normal group was used as a non-cardiomyopathy normal control (n=10); the control group included non-aerobic exercise after doxorubicin-induced cardiomyopathy (n=10); the experimental group I included aerobic exercise (3 m/min) after doxorubicin-induced cardiomyopathy (n=10); and experimental group II included aerobic exercise (8 m/min) after doxorubicin-induced cardiomyopathy. Rats in the treadmill training groups underwent treadmill training, which began at 2 weeks after the first intraperitoneal injection. At the end of the exercise period, we determined the heart weight change for each rat. Changes in the levels of oxidative stress enzymes (superoxide dismutase [SOD], thiobarbituric acid-reactive substances [TBARS], and catalase) in the cardiac tissue of rats from all four groups were examined at the end of the experiment. Results: Significant cardiac myocyte injury and increase in myocardial TBARS concomitant with a reduction in myocardial SOD and catalase were observed following cardiomyopathy (p<0.05). Significant cardiac tissue and increase in myocardial TBARS along with reduction in myocardial SOD and catalase were observed following cardiomyopathy (p<0.05). Oxidative parameters were significantly improved in the aerobic exercise groups compared with the control group. Conclusions: These findings indicate that aerobic exercise effectively prevents oxidative stress in rat models with cardiomyopathy.

Antiulcer activity of Trichosanthes cucumerina linn. against experimental gastro-duodenal ulcers in rats

  • Galani, VJ;Goswami, SS;Shah, MB
    • Advances in Traditional Medicine
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    • v.10 no.3
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    • pp.222-230
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    • 2010
  • Trichosanthes cucumerina Linn. (cucurbitaceae) is widely used in Indian folk medicine for variety of disease conditions. The aim of present study was to evaluate the antiulcer activity of 50% ethanolic extract of fruits of Trichosanthes cucumerina Linn. (TCFE) using various experimental models of gastric and duodenal ulceration in rats. Oral administration of 50% ethanolic extract of fruits of Trichosanthes cucumerina Linn. was evaluated in rats against ethanol, aspirin and pylorus ligated gastric ulcers as well as cysteamine-induced duodenal ulcers. In all the models studied, the antiulcer activity of TCFE compared with that of cimetidine (100 mg/kg, p.o.), an $H_2$ receptor antagonist. TCFE showed significant antiulcer activity in ethanol-induced and aspirin-induced gastric ulcer models. In 19 h pylorus ligated rats, significant reduction in ulcer index, total acidity and pepsin activity was observed with TCFE, when compared with the control group. Mucosal defensive factors such as pH, mucin activity and gastric wall mucous content was found to be increased with TCFE. TCFE was also, afforded remarkable protection in cysteamine-induced duodenal lesions. The antiulcer activity of TCFE was comparable with that of cimetidine. Thus, TCFE possess significant antiulcer activity against both gastric and duodenal ulcers in rats. The antiulcer activity may be attributed to its cytoprotective action and inhibition of acid secretary parameters.

A comparative study on the crustal structure models using microearthquakes in the southeastern part of the Korean peninsula from 1995 to 1996 (1995-96년 한반도 남동부 지역의 미소지진 자료를 이용한 지각구조 모델의 비교 연구)

  • Lee, Gi Hwa;Jeong, Tae Ung
    • Journal of the Korean Geophysical Society
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    • v.2 no.1
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    • pp.1-8
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    • 1999
  • Using the microearthquake data acquired from 1995 to 1996 through the seismic network operated by the Korea Institute of Geology, Mining & Materials (KIGAM), the three P-wave velocity models proposed by Lee (1979), Kim·Kim (1983) and Kim·Jung (1985) concerning the structure of the southeastern part of the Korean peninsula were examined in terms of the least square errors of the P-wave arrival times. The three models do not differ significantly in arrival time residuals except that the Lee's model gives slightly deeper focuses than the others. The layering of the crust of the peninsula is not clear as yet and to be studied by more earthquake and explosion data in the future.

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Active and Passive Protective Effect of CFC-101 (Pseudomonas Vaccine) in Mice (CFC-101(녹농균 백신)의 능동 및 수동면역 효과)

  • 박완제;조양제;김영지;김제학;박관하;김유삼;함경수
    • Biomolecules & Therapeutics
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    • v.2 no.4
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    • pp.326-330
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    • 1994
  • The treatment of pseudomonal infection is a perplexed problem because of its modest susceptibility to most of the major antibiotics. A novel Pseudomonas vaccine(CFC-101) was prepared from the outer membrane protein fractions of several Pseudomonas strains. In this study, we examined CFC-101's effectiveness in both active and passive immunization models. CFC-101 in mice at 0.2 mg/kg, i.p., given three times at two-day intervals, completely prevented the death caused by Pseudomonas aeruginosa. Antibody titer, in accordance with the protective effect in this active immunization, was elevated to its peak level following three consecutive administrations of CFC-101. Thereafter, antibody titer stayed at a constantly high level. Each outer membrane protein fraction from the four CFC-101 producers, exhibited good cross-protective effects in mouse infection models against different Fisher types of P. aeruginosa. In the passive immunization model, 21~336 $\mu\textrm{g}$/kg of anti-rabbit IgG to CFC-101, when mice being infected with a challenge strain, prevented the Pseudomonhas-induced death up to 60%. Therefore, the preventive effect of CFC-101 was verified in both the active and passive immunization models.

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Prediction Models of Residual Chlorine in Sediment Basin to Control Pre-chlorination in Water Treatment Plant (정수장 전염소 공정 제어를 위한 침전지 잔류 염소 농도 예측모델 개발)

  • Lee, Kyung-Hyuk;Kim, Ju-Hwan;Lim, Jae-Lim;Chae, Seon Ha
    • Journal of Korean Society of Water and Wastewater
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    • v.21 no.5
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    • pp.601-607
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    • 2007
  • In order to maintain constant residual chlorine in sedimentation basin, It is necessary to develop real time prediction model of residual chlorine considering water treatment plant data such as water qualities, weather, and plant operation conditions. Based on the operation data acquired from K water treatment plant, prediction models of residual chlorine in sediment basin were accomplished. The input parameters applied in the models were water temperature, turbidity, pH, conductivity, flow rate, alkalinity and pre-chlorination dosage. The multiple regression models were established with linear and non-linear model with 5,448 data set. The corelation coefficient (R) for the linear and non-linear model were 0.39 and 0.374, respectively. It shows low correlation coefficient, that is, these multiple regression models can not represent the residual chlorine with the input parameters which varies independently with time changes related to weather condition. Artificial neural network models are applied with three different conditions. Input parameters are consisted of water quality data observed in water treatment process based on the structure of auto-regressive model type, considering a time lag. The artificial neural network models have better ability to predict residual chlorine at sediment basin than conventional linear and nonlinear multi-regression models. The determination coefficients of each model in verification process were shown as 0.742, 0.754, and 0.869, respectively. Consequently, comparing the results of each model, neural network can simulate the residual chlorine in sedimentation basin better than mathematical regression models in terms of prediction performance. This results are expected to contribute into automation control of water treatment processes.

Carrier-Mediated Active Transport Models by Affinity-Switching Strategy

  • Lee, Sung-Kil;Araki, Koji
    • Proceedings of the Membrane Society of Korea Conference
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    • 1996.04a
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    • pp.5-10
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    • 1996
  • Active transport is one of the essential function of biological membrane transport systems, in which substrates are transported from lower to higher concentration side against their concentration gradient. In this article, we describe photo- and pH-induced active transport models by designing the functional carriers based on the affinity-switching strategy.

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A Method of Transient Stability Analysis Using ANN (신경회로망 부하모델을 이용한 과도안정도 해석기법)

  • Lee, J.P.;Lim, J.Y.;Kim, S.S.;Ji, P.S.
    • Proceedings of the KIEE Conference
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    • 2006.11a
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    • pp.329-331
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    • 2006
  • Load models are important for improving the accuracy of stability analysis. Load characteristics are changed for voltage and frequency condition. In this research, ANN with LMBP learning rule is used to construct the load model. Characteristics of some residential loads are tested under various voltage and frequency conditions. Acquired data are used to construct load models by ANN. Constructed ANN load model are applied to transient stability analysis.

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DUALITY IN MULTIOBJECTIVE FRACTIONAL PROGRAMMING PROBLEMS INVOLVING (Hp, r)-INVEX FUNCTIONS

  • Jayswal, Anurag;Ahmad, I.;Prasad, Ashish Kumar
    • Journal of applied mathematics & informatics
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    • v.32 no.1_2
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    • pp.99-111
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    • 2014
  • In this paper, we have taken step in the direction to establish weak, strong and strict converse duality theorems for three types of dual models related to multiojective fractional programming problems involving ($H_p$, r)-invex functions.

Electrical instabilities in p-channel polysilicon TFTs: role of hot carrier and self-heating effects

  • Fortunato, G.;Gaucci, P.;Mariucci, L.;Pecora, A.;Valletta, A.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08b
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    • pp.1065-1070
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    • 2007
  • The effects of hot carriers and self-heating on the electrical stability of p-channel TFTs have been analysed combining experimental data and numerical simulations. While hot carrier effects were shown not to induce appreciable degradation, self-heating related instability was found to more seriously affect the device characteristics. New models have been developed to explain the reported results.

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