• Clean Technology
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• v.20 no.2
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• pp.166-170
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• 2014

The continuous experiments were carried out using fixed-bed column packed with strong-acid cation exchange resin for the removal of lithium ions from aqueous solution. The parameters such as bed height, flow rate and inlet concentration were investigated. Breakthrough time ($t_{0.05}$), saturation time ($t_{0.95}$), and total amount of lithium ion removed (mtotal) were obtained from the breakthrough curves. The results showed that $t_{0.05}$ and $t_{0.95}$ decreased with decreasing bed height, and decreased with increasing inlet concentration and flow rate. mtotal increased with increasing inlet concentration and bed height, but decreased with increasing flow rate. Thomas model and Yoon-Nelson model equations were applied to the experimental data, the results showed that the breakthrough data gave a good fit to Thomas model equation.

• Water for future
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• v.18 no.1
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• pp.75-83
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• 1985

The applicability of ARMA(1, 1) multiseason model, which is in the beginning stage of active researches in the field of synthetic generation is evaluated with the streamflow data at the Nakdong stage gauging station on the main stem of the Nakdong River. The method of parameter estimation for the modelis reviewed and the statistical analysis of the generated seasonal streamflows such as corrlogram analysis and the computation of moments is made. The results obtained by ARMA(1, 1) multiseason model are compared with the historical streamflow data and also with those by two other multiseason models, namely, Thomas-Fiering model and Matalas AR(1) multiseason model. The seasonal streamflows grnerated by three multiseason models were annually summed up to form respective annual flow series whose statistics were compared with those of the annual flow series generated by three annual models, namely, AR(1), Matalas AR(1), and ARMA(1, 1) annual models. The possibility of ARMA(1, 1) multiseason model for the simultaneous generation of seasonal and annual streamflows is also evaluated.

• English & American cultural studies
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• v.17 no.1
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• pp.27-54
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• 2017

Brian Ascalon Roley's American Son, one of the outstanding Filipino American novels after the LA riots, critically deals with a racial issue of his community which has been intermingled with the myth of model minority. Gabe and Thomas, considered as obedient Filipino younger immigrants, are asked to achieve the American dream as a way to place themselves at the center of the mainstream white society. However, they recognize that they cannot be accepted as a suitable subject for the invincible racism deeply rooted in the society. While Tomas refuses to become a model minority by identifying himself with the Mexican, Gabe is expected to become an idealistic subject of model minority by his mother since he complies with the rules of the mainstream society. However, he accepts his brother's violent way of life in that violence is necessary to protect his family from the racial discrimination in America. Though he is his mother's hope for model minority, he recognizes the only condition to achieve her expectation is the American society where there is no racism at all. However, by taking the case of Gabe and Thomas, Roley suggests that the younger generation of Filipino American immigrants have no choice but to accept violence to survive in the American society because racism always threatens their life.

• Water for future
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• v.18 no.4
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• pp.335-345
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• 1985

The purpose of stochastic models for synthetic generation of river flows based on the short-term observed data is to provide abundant input data to the water resources systems of which the system performance and operation policy are to be determined beforehand. Among many of such models the Monte Carlo Method of synthetic generation, which is usually known to be appropriate for annual data generation, is employed to check if it can be applied for the generation of monthly flows. For the purpose of comparisons the statistical parameters of the generated monthly flows by Monte Carlo model based on the appropriate probability distribution for each month were compared with those of the generated flows by Thoms-Fiering multiseason model and with those of the observed monthly flows. On the other hand, the statistical parameters of the annual river flows obtained by adding the generated monthly flows year by year based on the Monte Carlo and Thomas-Fiering models were compared with those of the annual flows generated directly by annual Monte Carlo model with reference to those for the observed annual river flows. Based on the above comparative studies, the discussions are made and conclusions derived.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.5 no.4
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• pp.357-368
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• 1993

With the assumption of the diffusion dominated flow, a numerical model has been developed for undertow and turbulence structure under the breaking wave by using the $textsc{k}$-$\varepsilon$ turbulence model. Undertow is a strong mean current which moves seqwards below the level of wave trough in the surf zone. The turbulence, generated by wave breaking in the roller, spreads and dissipates downwards. The governing equations are composed of the equation of motion with the period-averaged shear stress due to waves; $textsc{k}$- and $\varepsilon$-equations with the turbulence energy Production due to wave breaking. They are discretised by the three-level fully implicit scheme, which can be solved by using Thomas algorithm. The model gives good agreements with measurements except for the station that is closest to the breaking point.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.709-710
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• 2002

Cancer angiogenesis is simulated using a two dimensional model. Governing equation of angiogenesis is a TAE (Tumor angiogenesis factor) conservation equation in time and space. A stochastic process model is utilized to simulate vessel formation, proliferation, and migration to a cancer pellet. Numerical results are presented especially in case of growing cancer.

• Advances in environmental research
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• v.3 no.3
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• pp.231-251
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• 2014

The present study examines the phosphate adsorption potential and behavior of mixture of Ground Burnt Patties (GBP), a solid waste generated from cooking fuel used in earthen stoves and Red Soil (RS), a natural substance in fixed bed column mode operation. The characterization of adsorbent was done by Proton Induced X-ray Emission (PIXE), and Proton Induced ${\gamma}$-ray Emission (PIGE) methods. The FTIR spectroscopy of spent adsorbent reveals the presence of absorbance peak at $1127cm^{-1}$ which appears due to P = O stretching, thus confirming phosphate adsorption. The effects of bed height (10, 15 and 20 cm), flow rate (2.5, 5 and 7.5 mL/min) and initial phosphate concentration (5 and 15 mg/L) on breakthrough curves were explored. Both the breakthrough and exhaustion time increased with increase in bed depth, decrease in flow rate and influent concentration. Thomas model, Yoon-Nelson model and Modified Dose Response model were used to fit the column adsorption data using nonlinear regression analysis while Bed Depth Service Time model followed linear regression analysis under different experimental condition to evaluate model parameters that are useful in scale up of the process. The values of correlation coefficient ($R^2$) and the Sum of Square Error (SSE) revealed the Modified Dose Response model as the best fitted model to the experimental data. The adsorbent mixture responded effectively to the desorption and reusability experiment. The results of this finding advocated that mixture of GBP and RS can be used as a low cost, highly efficient adsorbent for phosphate removal from aqueous solution.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.17
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• pp.7097-7103
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• 2014

Over-expression of de novo lipogenesis (DNL) genes is associated with the prognosis of various types of cancers. However, the effects of single nucleotide polymorphisms (SNPs) in these genes on recurrence and survival of non-small cell lung cancer (NSCLC) patients after surgery are still unknown. In this study, a total of 500 NSCLC patients who underwent surgery treatment were included. Eight SNPs in 3 genes (ACACA, FASN and ACLY) of the DNL pathway were examined using the Sequenom iPLEX genotyping system. Multivariate Cox proportional hazards regression and Kaplan-Meier curves were used to analyze the association of SNPs with patient survival and tumour recurrence. We found that two SNPs in the FASN gene were significantly associated with the recurrence of NSCLC. SNP rs4246444 had a significant association with lung cancer recurrence under additive model (hazard ratio [HR], 0.82; 95% confidence interval [95%CI], 0.67-1.00; p=0.05). Under the dominant model, rs4485435 exhibited a significant association with recurrence (HR, 0.75; 95%CI, 0.56-1.01; p=0.05). Additionally, SNP rs9912300 in ACLY gene was significantly associated with overall survival in lung cancer patients (HR, 1.41; 95%CI, 1.02-1.94, p=0.04) under the dominant model. Further cumulative effect analysis showed moderate dose-dependent effects of unfavorable SNPs on both survival and recurrence. Our data suggest that the SNPs in DNL genes may serve as independent prognostic markers for NSCLC patients after surgery.

• Journal of the Korean Statistical Society
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• v.36 no.1
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• pp.111-127
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• 2007

The logistic distribution is generalized using the Marshall-Olkin scheme and its generalization. Some properties are studied. First order autoregressive time series model with Marshall-Olkin semi-logistic distribution as marginal is developed and studied.

• Advances in environmental research
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• v.12 no.1
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• pp.17-40
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• 2023

This article presents studies of the adsorption process in a continuous system of fluoride solutions at a concentration of 30 mg/L using a bone char packed in fixed-bed columns, as well as regeneration studies in the same system using HNO₃, HCl and NaOH at 0.01, 0.1 and 1 M. The Thomas Model, Artificial Neural Networks (ANNs), Numerical Integration and Mass Transfer Zone were used for the modeling of asyemmetrical breakthrough curves obtained from the fluoride adsorption on bone char. The maximum adsorption capacity of the breakthrough curves was estimated, and various design parameters of the columns were obtained for the different operating conditions. Results showed that an improvement in the modeling capabilities of the Thomas model can be obtained using ANNs. Moreover, ANNs are useful for determining reasonable and accurate design parameters of packed-bed adsorption columns. This modeling approach can be useful for the process system engineering of dynamic adsorption systems involved in the field of water treatment and purification. It is important to highlight that the obtained results indicate that, when using HCl or HNO₃ at a concentration of 0.1 M, a large number of adsorption-desorption cycles are obtained and, therefore, the highest values of adsorption capacity, which leads to a reduction in operation costs.