• Journal of Korean Society of Industrial and Systems Engineering
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• v.44 no.4
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• pp.12-22
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• 2021

This article suggests the machine learning model, i.e., classifier, for predicting the production quality of free-machining 303-series stainless steel(STS303) small rolling wire rods according to the operating condition of the manufacturing process. For the development of the classifier, manufacturing data for 37 operating variables were collected from the manufacturing execution system(MES) of Company S, and the 12 types of derived variables were generated based on literature review and interviews with field experts. This research was performed with data preprocessing, exploratory data analysis, feature selection, machine learning modeling, and the evaluation of alternative models. In the preprocessing stage, missing values and outliers are removed, and oversampling using SMOTE(Synthetic oversampling technique) to resolve data imbalance. Features are selected by variable importance of LASSO(Least absolute shrinkage and selection operator) regression, extreme gradient boosting(XGBoost), and random forest models. Finally, logistic regression, support vector machine(SVM), random forest, and XGBoost are developed as a classifier to predict the adequate or defective products with new operating conditions. The optimal hyper-parameters for each model are investigated by the grid search and random search methods based on k-fold cross-validation. As a result of the experiment, XGBoost showed relatively high predictive performance compared to other models with an accuracy of 0.9929, specificity of 0.9372, F₁-score of 0.9963, and logarithmic loss of 0.0209. The classifier developed in this study is expected to improve productivity by enabling effective management of the manufacturing process for the STS303 small rolling wire rods.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.3
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• pp.237-246
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• 1995

Larvae of the freshwater shrimp, Macrobrachium nipponense were reared in the laboratory at constant condition $(25^{\circ}C,\;7\%o)$, and their feeding rate, oxygen consumption rate, and growth rate were measured in regular intervals of time during larval development. Regression equations describing rates of feeding, growth and respiration as functions of time during individual larval molt cycles were inserted in a simulation model in order to analyse time-dependent patterns of variation as well as in bioenergetic efficiencies. Absolute values for feeding, growth, respiration and assimilation showed clear changes during the molt cycle, The absolute and specific values of respiration (R: R/C) showed small variation during the individual molt cycles. Significance of respiration in relation to growth (G) increased within the carbon budget, respiration rate (R/C) outbalanced growth rate (G/C) in late premolt. When the portion of metabolizable carbon is respired (R/G), metabolic coefficient was < 1 (i.e. R$(K_2)$ decreased concurrently, In cumulative carbon budget, total feeding was $491.54\;{\mu}g$ C/ind., assimilation was $85.3\%$, respiration was $47.7\%$, and growth was $37.6\%$ from hatching to postlarval stage.

• Fashion & Textile Research Journal
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• v.6 no.6
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• pp.815-824
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• 2004

In academic and/or practitioner literature, the assortment planning for fashion sensitive products is rarely systematically studied, and organized in an objective format. The purpose of this study was to develop a suggested assortment planning model for women's clothing retail buyers by integrating a conceptual assortment planning model and a practical-use assortment planning model, which are also developed in this study. In developing the conceptual model, this research categorized and organized the pieces of assortment planning activities illustrated in available literature. In developing the practical-use model, ten women's dress buyers from department stores and specialty stores were interviewed. The contents of the interview dictation were classified and summarized by concepts and variables. The summary was validated by the interviewees and recontextualized for the practical-use model. Five experts compared the conceptual and practical-use models, adjusted the discrepancies, and integrated into the suggested model. In addition, a questionnaire asking review of all functional activities of the suggested model was sent to interviewees to ascertain its validity. As the result, assortment planning process was determined at abstract level as the following: (a) recognize problem, (b) search for information, (c) evaluate qualitative value of product, (d) evaluate quantitative value of product, (e) plan product selection, and (f) plan sales.

• Archives of Pharmacal Research
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• v.20 no.5
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• pp.414-419
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• 1997

Gastrointestinal irritation is the most frequent adverse effect in patients chronically taking nonsteroidal antiinflammatory drugs (NSAIDs) for the treatment of arthritic conditions. Gastroprotective effect of DA-9601, a new antiulcer agent from Artemisiae Herba extract, against NSAID was evaluated in a rat model of arthritis that is similar in many aspects to human rheumatoid arthritis. Daily oral dosing of naproxen (30 mg/kg), one of the most commonly used NSAID, induced apparent gastric lesions as well as a significant decrease in mucosal prostagiandin $E_2;(PGE_2)$ and prostagiandin F_${1{\alpha}}$$(PGF_{1{\alpha}})$ levels. Coadministration of DA-9601 prevents naproxen-induced mucosal injury and depletion of prostaglandins, in a dose-related manner. DA-9601 did not alter the antiinflammatory or analgesic effect of naproxen. The present results suggest that DA-9601 may be useful as a mucoprotectant against NSAIDs in clinical practice.

• Steel and Composite Structures
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• v.17 no.1
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• pp.47-67
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• 2014

Due to thermal expansion, the structural behaviour of beams in steel structures subjected to temperature increase will be affected. This may result in the failure of the structural members or connection due to extra internal force in the beam induced by the thermal increase. A method to release some of the thermally generated internal force in the members is to allow for some movements at the end supports of the member. This can be achieved by making the plane of the end-plate of the connection slanted instead of vertical as in conventional design. The present paper discusses the mechanical behaviour of beams with bolted slant end-plate connection under symmetrical gravity loads, subjected to temperature increase. Analyses have been carried out to investigate the reduction in internal force with various angles of slanting, friction factor at the surface of the connection, and allowable temperature increase in the beam. The main conclusion is that higher thermal increase is tolerable when slanting connection is used, which means the risk of failure of structures can be reduced.

• Computers and Concrete
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• v.2 no.3
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• pp.189-202
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• 2005

This paper presents an analysis of some experimental results concerning micro-structural tests, permeability measurements and strain-stress tests of four types of High-Performance Concrete, exposed to elevated temperatures (up to $700^{\circ}C$). These experimental results, obtained within the "HITECO" research programme are discussed and interpreted in the context of a recently developed mathematical model of hygro-thermal behaviour and degradation of concrete at high temperature, which is briefly presented in the Part 2 paper (Gawin, et al. 2005). Correlations between concrete permeability and porosity micro-structure, as well as between damage and cracks' volume, are found. An approximate decomposition of the thermally induced material damage into two parts, a chemical one related to cement dehydration process, and a thermal one due to micro-cracks' development caused by thermal strains at micro- and meso-scale, is performed. Constitutive relationships describing influence of temperature and material damage upon its intrinsic permeability at high temperature for 4 types of HPC are deduced. In the Part II of this paper (Gawin, et al. 2005) effect of two different damage-permeability coupling formulations on the results of computer simulations concerning hygro-thermo-mechanical performance of concrete wall during standard fire, is numerically analysed.

• The Journal of Korean Academic Society of Nursing Education
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• v.23 no.2
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• pp.184-193
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• 2017

Purpose: This study examined the effects of self-leadership and critical thinking disposition on adaptation to college among nursing students. Methods: A descriptive study was conducted with 325 nursing students using a self-report questionnaire. Data were analyzed using a t-test, one way ANOVA, $Scheff{\dot{e}}$ test, Pearson correlation coefficients, and stepwise multiple regression analysis with SPSS 20.0. Results: The mean score of college adaptation was 3.22. Significant predictor variables affecting adaptation to college were satisfaction in major (${\ss}=.45$, p<.001), behavior-focused strategies (${\ss}=.16$, p<.001), leadership level (${\ss}=.15$, p=.003), and grade (${\ss}=.11$, p=.016). The explanation power of this regression model was 32.2% and was statistically significant (F=64.60, p<.001). Conclusion: The results of this study indicated that an effective college adaptation program should be developed by including improvement of satisfaction in major, behavior-focused strategies, and leadership level.

• Water for future
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• v.26 no.2
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• pp.39-48
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• 1993

Since major reason of disaster in coastal area is wave action, prediction of wave deformation is one of the most important problems to ocean engineers. Wave deformations are due to physical factors such as shoaling effect, reflection, diffraction, refraction, scattering and radiation etc. Recently, numerical models are widely utilized to calculate wave deformation. In this study, the mild slope equation was used in calculatin gwave deformation which considers diffraction and refraction. In order to slove the governing equation, finite element method is introduced. Even though this method has some difficulties, it is proved to predict the wave deformation accurately even in complicated boundary conditions. To verify the validity of the numerical calculation, experiments were carried out in a model harbour of rectangular shape which has mild slope bottom. The results by F.E.M. are compared with those of both Lee's method and the experiment. The results of these three methods show reasonable agreement.

• Journal of Marine Bioscience and Biotechnology
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• v.12 no.1
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• pp.50-58
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• 2020

Sphacelaria is a filamentous brown algal genus that can be epibiotic on macroalgae, marine plants, and sea turtles. Its important role in benthic ecosystems, exposure to different stressors (e.g., grazing), and use as a model organism make Sphacelaria ideal for assessing physiological responses of organisms to environmental inputs. Single-cell RNA sequencing is a powerful new probe for understanding environmental responses of organisms at the molecular (transcriptome) level, capable of delineating gene regulation in different cell types. In the case of plants, this technique requires protoplasts ("naked" plant cells). The existing protoplast isolation protocols for Sphacelaria use non-commercial enzymes and are low-yielding. This study is the first to report the production of protoplasts from Sphacelaria fusca (Hudson) S.F. Gray, using a combination of commercial enzymes, chelation, and osmolarity treatment. A simple combination of commercial enzymes (cellulase Onozuka RS, alginate lyase, and driselase) with chelation pretreatment and an increased osmolarity (2512 mOsm/L H₂O) gave a protoplast yield of 15.08 ± 5.31 × 10⁴ protoplasts/g fresh weight, with all the Sphacelaria cell types represented. Driselase had no crucial effect on the protoplast isolation. However, the increased osmolarity had a highly significant and positive effect on the protoplast isolation, and chelation pretreatment was essential for optimal protoplast yield. The protocol represents a significant step forward for studies on Sphacelaria by efficiently generating protoplasts suitable for cellular studies, including single-cell RNA sequencing and expression profiling.

• Journal of Nutrition and Health
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• v.29 no.10
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• pp.1072-1079
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• 1996

This study was performed to elucidate the mechanism of dietary protein level on renal function through lipid and eicosanoids metabolism. Male rats of 337.8$\pm$5.7g body weight were undergone unilateral nephrectomy or sham-operation. The rats were divided into high protein(40% casein), normal protein(15% casein) and low protein(8% casein) diet groups and fed experimental diets ad libitum for 24 weeks. The results are summarized as follows. Serum total lipid, cholesterol and HDL-cholesterol of rats in 15% and 40% casein groups were higher than those of 8% casein group. But serum triglyceride was affected neither by uninephrectomy nor by dietary protein level. Serum thromboxane(TX) B2 and 6-keto prostaglandin F1$\alpha$ increased with increasing dietary protein level. Serum prostaglandin(PG) E2 was not affected by uninephrectomy nor by dietary protein level. Urinary PGE2 and TXB2 excretion tended to be lower in uninephrectomized groups. Renal tissue concentration of TXB2 was lower in uninephrectomized groups and in high protein group. These results suggest the possibility that the effects of dietary protein level on renal function could be due to changes in lipid and eicosanoids metabolism.