• Journal of Ocean Engineering and Technology
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• v.36 no.4
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• pp.251-269
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• 2022

The process-based XBeach model has numerous empirical parameters because of insufficient understanding of hydrodynamics and sediment transport on the nearshore; hence, it is necessary to calibrate parameters to apply to various study areas and wave conditions. Therefore, the calibration process of parameters is essential for the improvement of model performance. Generally, the trial-and-error method is widely used; however, this method is passive and limited to various and comprehensive parameter ranges. In this study, the Generalized Likelihood Uncertainty Estimation (GLUE) method was used to estimate the optimal range of three parameters (gamma, facua, and gamma2) using morphological field data collected in Maengbang beach during the four typhoons that struck from September to October 2019. The model performance and optimal range of empirical parameters were evaluated using Brier Skill Score (BSS) along with the baseline profiles, sensitivity, and likelihood density analysis of BSS in the GLUE tools. Accordingly, the optimal parameter combinations were derived when facua was less than 0.15 and simulated well the shifting shape, from crescentic sand bar to alongshore uniform sand bars in the surf zone of Maengbang beach after storm impact. However, the erosion and accretion patterns nearby in the surf zone and shoreline remain challenges in the XBeach model.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.4
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• pp.365-370
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• 2010

The pollen dispersal by wind can make an important to understanding the viability and evolution of plants in ecological and agricultural science. Modelling can be applied to evaluate concerns about the spread of engineered pollens from genetically modified (GM) crops. Here, we are using gamma model to estimate the level of dispersal distance of pollen in the cross-pollination between two different maize (Zea mays L.) cultivars in GMO field of Korea University during the year 2010. The result of estimation of model indicates maximum pollen dispersal distance of estimated proportion of cross-pollination of maize was reached to 0.1% in 525 meter northwest due to the wind. We identify further measurements necessary to improve the accuracy of the model predictions.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6255-6259
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• 2015

Purpose: To evaluate the prognostic value of alkaline phosphatase (ALP) and gamma-glutamyltransferase (GGT) in gallbladder cancer (GBC). Materials and Methods: Serum ALP and GGT levels and clinicopathological parameters were retrospectively evaluated in 199 GBC patients. Receiver operating characteristic (ROC) curve analysis was performed to determine the cut-off values of ALP and GGT. Then, associations with overall survival were assessed by multivariate analysis. Based on the significant factors, a prognostic score model was established. Results: By ROC curve analysis, $ALP{\geq}210U/L$ and $GGT{\geq}43U/L$ were considered elevated. Overall survival for patients with elevated ALP and GGT was significantly worse than for patients within the normal range. Multivariate analysis showed that the elevated ALP, GGT and tumor stage were independent prognostic factors. Giving each positive factor a score of 1, we established a preoperative prognostic score model. Varied outcomes would be significantly distinguished by the different score groups. By further ROC curve analysis, the simple score showed great superiority compared with the widely used TNM staging, each of the ALP or GGT alone, or traditional tumor markers such as CEA, AFP, CA125 and CA199. Conclusions: Elevated ALP and GGT levels were risk predictors in GBC patients. Our prognostic model provides infomration on varied outcomes of patients from different score groups.

• Journal of Radiation Industry
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• v.12 no.4
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• pp.277-285
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• 2018

Patients administered radioisotope for medical purposes are regulated by each country to quarantine them until their body's radioactivity contents decrease below release criteria. To predict the quarantine period and provide it to medical staffs and patients, it is necessary to approach the assessment of the exposure dose of persons due to patients in a realistic manner. For this purpose, a whole-body effective half-life should be applied to the dose assessment equation instead of the physical half-life. In this study, we constructed a bio-kinetic model for each nuclear species based on the ICRP publication to obtain a whole-body effective half-life of 10 unsealed gamma-ray emitting nuclei from the notification of Nuclear Safety and Security Commission, and calculated the effective half-life mathematically by simulating the distribution of the radioisotope administered in the whole body as well as each organ scale. The whole-body effective half-life of $^{198}Au$, $^{67}Ga$, $^{123}I$, $^{111}In$, $^{186}Re$, $^{99m}Tc$, and $^{201}TI$ were 1,93, 2.57, 0.295, 2.805, 1.561, 0.245, and 2.397 days respectively. However, it was found to be undesirable to offer a single value of the effective half-life of $^{125}I$, $^{131}I$, and $^{169}Yb$ because the changes in the effective half-life show no linearity. A bio-kinetic model created for the internal exposure assessment has been shown to be possible to calculate the effective half-life of radioisotopes administered in the patient's body, but subsequent studies of radiolabeled compounds are required as well.

• International Journal of Computer Science & Network Security
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• v.23 no.2
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• pp.183-192
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• 2023

Radiofrequency ablation (RFA) is an alternative treatment for liver cancer to the surgical intervention preferred by surgeons. However, the main challenge remains the use of RF for the ablation of large tumours (i.e., tumours with a diameter of >3 cm). For large tumours, RFA takes a large duration in the ablation process compared with surgery, which increases patient pain. Therefore, RFA for large tumours is not preferred by surgeons. The currently materials used in RF electrodes, such as the nickeltitanium alloy (nitinol), are characterized by low thermal and electrical conductivities. On the other hand, the use of materials that have high thermal and electrical conductivities, such as titanium aluminide alloy (gamma titanium), produces more thermal energy for tumours. In this paper, we developed a cool-tip RF electrode model that uses nickel-titanium alloy and replaced it with titanium aluminide alloy by using the finite element model (FEM). The aim of this paper is to study the effect of the thermal and electrical conductivities of gamma titanium on the ablation volume. Results showed that the proposed design of the electrode increased the ablation rate by 1 cm³ /minute and 6.3 cm³/10 minutes, with a decrease in the required time ablation. Finally, the proposed model reduces the ablation time and damages healthy tissue while increasing the ablation volume from 22.5% cm³ to 62.5% cm³ in ten minutes compared to recent studies.

• Journal of Korea Water Resources Association
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• v.38 no.4 s.153
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• pp.271-280
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• 2005

The goal of this study is to recommend a new type of stage-discharge rating curve ($Q=p(h-e)^{\beta}-{\gamma}$) useful for satisfying divergence, and one other seemingly irresolvable problem related to exited rating curves, while also extending this rating curve model. The problem of divergence is that during the finding of the CZF (cease-to-zero flow) parameter e and while minimizing the sum of total errors of the estimated curve, the exponential parameter ${\beta}$ become an abnormally large value. The insoluble problem is that when the value e is greater then the recorded minimum at the gauged stage, it is impossible to have a negative logarithm value (h-e). The two problems above can be satisfied by adapting the control value ${\gamma}$, which affects the reduction of ${\gamma}$ and gives us the possibility of controlling (h-e) over zero. The study results show that the effects of parameter ${\gamma}$ are very similar to that of e when conducting physical and sensitivity analyses. This system can be used towards developing a new stage-discharge rating curve for river discharge, for use in evaluating the acceptability of existing stage-discharge rating curves generated by using hydrologic analyses at all stations.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.4
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• pp.534-541
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• 2009

The aim of this study was to evaluate the effects of gamma irradiation (${\gamma}$-irradiation) at doses of 15, 30 and 45 kGy on chemical composition, anti-nutritional factors, ruminal dry matter (DM) and crude protein (CP) degradibility, in vitro CP digestibility and to monitor the fate of true proteins of full-fat soybean (SB) in the rumen. Nylon bags of untreated or ${\gamma}$-irradiated SB were suspended in the rumens of three ruminally-fistulated bulls for up to 48 h and resulting data were fitted to a nonlinear degradation model to calculate degradation parameters of DM and CP. Proteins of untreated and treated SB bag residues were fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Digestibility of rumen undegraded CP was estimated using the three-step in vitro procedure. The chemical composition of raw and irradiated soybeans was similar. Results showed that phytic acid in ${\gamma}$-irradiated SB at dose of 30 kGy was eliminated completely. The trypsin inhibitor activity of 15, 30 and 45 kGy ${\gamma}$-irradiated SB was decreased (p<0.01) by 18.4, 55.5 and 63.5%, respectively. From in sacco results, ${\gamma}$-irradiation decreased (p<0.05) the washout fractions of DM and CP at doses of 30 and 45 kGy, but increased (p<0.05) the potentially degradable fractions. Gamma irradiation at doses of 15, 30 and 45 kGy decreased (p<0.05) effective degradability of CP at a rumen outflow rate of 0.05 $h^{-1}$ by 4.4, 14.4 and 26.5%, respectively. On the contrary, digestibility of ruminally undegraded CP of irradiated SB at doses of 30 and 45 kGy was improved (p<0.05) by 12 and 28%, respectively. Electrophoretic analysis of untreated soybean proteins incubated in the rumen revealed that ${\beta}$-conglycinin subunits had disappeared at 2 h of incubation time, whereas the subunits of glycinin were more resistant to degradation until 16 h of incubation. From the SDS-PAGE patterns, acidic subunits of 15, 30 and 45 kGy ${\gamma}$-irradiated SB disappeared after 8, 8 and 16 h of incubation, respectively, while the basic subunits of glycinin were not degraded completely until 24, 48 and 48 h of incubation, respectively. It was concluded that ${\gamma}$-irradiated soybean proteins at doses higher than 15 kGy could be effectively protected from ruminal degradation.

• Communications for Statistical Applications and Methods
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• v.9 no.2
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• pp.515-520
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• 2002

In general, we use the hierarchical Poisson-gamma model for the Poisson data in generalized linear model. Time effect will be emphasized for the analysis of the observed data to be collected annually for the time period. An extended model with time effect for estimating the effect is proposed. In particularly, we discuss the Quasi likelihood function which is used to numerical approximation for the likelihood function of the parameter.

• Communications for Statistical Applications and Methods
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• v.9 no.1
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• pp.1-11
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• 2002

This paper discusses problems of the Poisson Mixture model which Is widely used to decide the effective words in judging relevant document. Gamma Distribution model and Gauss Patterns model as an alternative of the Poisson Mixture model are studied. Classification experiments by using TREC sub-collection, WSJ[1,2] with MGQUERY and AidSearch3.0 system are discussed.

• The Korean Journal of Pharmacology
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• v.32 no.1
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• pp.23-29
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• 1996

According to the traditional receptor model, competitive antagonists share with agonists the ability to bind to a common site on receptors, but they are different from agonist in that they cannot trigger the biological response-i.e., they lack intrinsic efficacy. Recent findings extend the model by indicating that not all antagonists display an intrinsic efficacy of zero but that some display 'inverse agonism'. In the present study we studied the inverse agonism at $A_1$ adenosine receptors in membranes prepared from rat cerebral cortex. Eight commercially available $A_1$ adenosine receptor antagonists (CGS-15943, ADPX, CPT, DPCPX, DPX, N-0840, PACPX and 8-PT) were screened for inverse agonism by measuring the extent of $[^{35}S]guanosine-5'-({\gamma}-thio)$ triphosphate $([^{35}S]GTP_{\gamma}S)$ binding to G proteins. The agonist-induced stimulation of $[^{35}S]GTP_{\gamma}S$ bindings was completely blocked in the presence of $A_1$ adenosine receptor antagonists. Under optimal conditions, two types of antagonists could be distinguished. Seven antagonists including DPCPX decreased the basal $[^{35}S]GTP_{\gamma}S$ binding in the absence of agonist, displaying inverse agonist activity. One (CGS-15943) had no effect on the basal bindings. N-ethylmaleimide treatment reduced the basal bindings as well as agonist-mediated stimulation of $[^{35}S]GTP_{\gamma}S$ bindings, indicating that a substantial amount of this binding reflects an activated state of the C proteins. In good agreement with these findings, 0.1 mM GTP decreased the apparent affinity of the receptors for the agonist PIA, increased that for DPCPX, and had no effect on that for CGS-15943.