• Membrane and Water Treatment
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• v.4 no.1
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• pp.27-51
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• 2013

During cleaning steps, ultrafiltration membranes are mechanically and chemically stressed. This may result in membrane degradations and failures. In this paper, polysulfone membranes were used to evaluate membrane deteriorations by commercial detergents in static conditions. Ageing of the membrane was simulated by immersing samples in solutions containing commercial detergents with various concentrations, temperatures and times defined by experimental designs. Indeed, an innovative approach in the chemical membranes ageing researches, based on methodological tools, was used in order to achieve significant ageing experiments without using an accelerated ageing protocol. The macroscopic changes were monitored by permeability measurements and mechanical strength tests coupled with a microscopic characterization by ATR-FTIR and HRSEM. The present work details results obtained for three commercial detergents: an alkaline, an acidic and an enzymatic detergent. It was found that the detergents used in the industrial advised conditions (concentration, temperature and time of contact) were not detrimental for membrane properties (permeability and elongation at break) and so for the quality of the produced water. Over the industrial cumulated time of contact, different ageing effects can be observed and compared with the ones induced by NaOCl.

• Journal of Ocean Engineering and Technology
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• v.34 no.4
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• pp.263-271
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• 2020

In this study, we performed a three-dimensional (3D) topology optimization of a fixed offshore structure to enhance its structural stiffness. The proposed topology optimization is based on the solid isotropic material with penalization (SIMP) method, where a volume constraint is applied to utilize an equivalent amount of material as that used for the rule-based scantling design. To investigate the effects of the main legs of the fixed offshore structure on its structural stiffness, the leg region is selectively considered in the design domain of the topology optimization problem. The obtained optimal designs and the rule-based scantling design of the structure are manufactured by 3D metal printing technology to experimentally validate the topology optimization. The behaviors under compressive loading of the obtained optimal designs are compared with those of the rule-based scantling design using a universal testing machine (UTM). Based on the structural experiments, we concluded that by employing the topology optimization method, the structural stiffness of the structure was enhanced compared to that of the rule-based scantling design for an equal amount of the fabrication material. Furthermore, by effectively combining the topology optimization and rule-based scantling methods, we succeeded in enhancing the structural stiffness and improving the breaking load of the fixed offshore structure.

• Journal of Fashion Business
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• v.17 no.6
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• pp.44-59
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• 2013

The modern people do express their personalities by appearance and actively use the appearance as the social tools, and the attractive appearance largely does influence the human relationship. As the appearance's importance is being magnified, the attractive appearance and favourable impression is an important standard for job performance and social position, and used as the way to reach the social goal. This study does investigate the design's kind and character of the beard which belongs to the male exclusive property and compare the differences of the impression's formation according to the beard design. The empirical results confirmed that the male beard design formated the various impressions according to the designs and their mutual relationship existed. Therefore, the beard is a symbol of maleness and an expression for the social position and personal character, whereas it possesses the very important meaning as the influencing factor on the impression's change. First, the pre stimuli were finished through the pre survey for composition of questionnaire in order to evaluate the impression after selection of experimental models and beard types for measuring instruments. Second, sixty three university students were surveyed by pre stimuli and questionnaire as pre experiment, and afterwards the measuring instruments and experimental design were revised. Third, the stimuli completed (nine beard designs) were intentionally well distributed as questionnaire by sex and ages in Seoul metropolitan and her environment. and the factorial analysis and the coefficient of Cronbach's ${\alpha}$ for reliability test were completed for questionnaire's validity using SPSS/PC+ Window Ver. 12.0.

• Atmosphere
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• v.31 no.4
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• pp.361-376
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• 2021

"Gangwon Yeongdong Wind Experiments (G-WEX) Pilot Study: Downslope windstorms in the Taebaek Mountains, South Korea" is promoted based on joint organization by Gangwon Regional Office of Meteorology and National Institute of Meteorological Research and participation by 12 institutions to understand the mechanism in development of Yeongdong wind phenomena. The special observation (G-WEX) involved total of 5 intensive observations in March 2020 and April 2020. To collect the data necessary for the research on Yeongdong wind phenomena, (1) high-resolution surface observation network was used to examine surface wind and (2) atmospheric soundings were observed by using Rawinsonde, Wind profiler, Wind Lidar, and Drone. This study covers the detailed information on the special observational experiments for downslope windstorms in the leeward of the Taebaek Mountains, named as the Yeongdong wind, including the observational strategies, experimental designs, and pilot studies during the Intensified Observing Period (IOPs). According to 2020 G-WEX observation results, downslope windstorms were observed in 2~3 km of upper atmosphere when the strong winds happened around the top of the mountain near Daegwallyeong. Also, dry adiabatic expansion related to downslope windstorms caused temperature rise and led to formation of an inversion layer in altitude below 2.5 km. Bands of strong wind were located right under the altitude where downslope windstorms are observed with temporal rise of the temperature. As these are preliminary observation results, there needs to be continuous related researches and high-resolution weather observation.

• Journal of the Korea Fashion and Costume Design Association
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• v.12 no.4
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• pp.137-147
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• 2010

This study set out to make experimental clothes by giving variations to the connecting part of a seamless sweater, propose designs and composition approaches to improve the wearing sensation and satisfaction with appearance through wearing trials, and provide basic data that would be of practical help to follow-up study on seamless knit and the growth of seamless knit in the Korean knit industry. The connecting part is the biggest characteristic and the most important part in seamless knitwear and affect the functionality and fitness of the clothes and the appearance of the armhole. The investigator thus made five different pieces of experimental clothes according to the composition methods for connecting part and put them to the test by a group of experts for appearance assessment. The assessment results were analyzed through Analysis of variance(ANOVA), and the items with similar results were put to the Duncan test for intergroup comparison. According to the analysis results, experimental clothes C and E received the highest evaluation in almost every assessment item, whereas experimental clothes A did the lowest appearance evaluation.

• Journal of Sasang Constitutional Medicine
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• v.30 no.3
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• pp.1-24
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• 2018

Objective This study was aimed to provide the information about Cheongsimyeonja-tang by domestic papers and theses. Method 50 Domestic papers related to Cheongsimyeonja-tang were selected according to the criteria. These papers were classified and analyzed by research designs, methods and results. Result The following results were obtained in this study. 1. 19 experimental studies on the effect of Cheongsimyeonja-tang were mainly focused on anti-aging, followed by anti-allergy, anti-inflammation, improvement of immune system. And there were 4 experimental studies on the safety of Cheongsimyeonja-tang, proving safety by acute toxicity test, nephrotoxicity test, drug interaction, and test of residual ingredients after decoction. 2. 25 clinical studies on the effect of Cheongsimyeonja-tang were mainly focused on cardiovascular and cerebral vascular diseases, followed by psychiatric and otologic disorder, dermatologic and musculoskeletal diseases. Also, there were 2 studies on the effect of Cheongsimyeonja-tang for diabetes insipidus, macular degeneration, digestive disorder in terminal cancer, drug-induced hepatitis. 3. More evidenced studies on Cheongsimyeonja-tang are needed and it is recommended that psychiatric questionnaire should be used for assessing the effects of Cheongsimyeonja-tang.

• Educational Technology International
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• v.14 no.1
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• pp.75-108
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• 2013

The purpose of this study is to find a way to improve digital textbooks for self-regulated learning by applying cognitive scaffolding designs to an elementary math digital textbook and examining the effectiveness of the system. Hence this study was conducted in two steps. First, a framework for scaffolding design was devised by examining the problems and difficulties students encounter when using a mathematics digital textbook. Second, after the digital textbook was revised by applying the scaffolding design frameworks, the effectiveness of the scaffolding framework was examined by comparing students' achievement levels in an experimental group and that of students in a control group. Seventy fifth-graders participated in this study. Students were divided into two groups: an experimental group and a control group. The students in the experimental group studied with the revised version of the digital textbook and the students in the control group studied with the original version of the digital textbook. The students received a pretest before the experiment. After the experiment, they took an achievement test and completed a usability questionnaire. The data were analyzed by ANCOVA with the SPSS Windows version. The results revealed that the students who used the revised program (to which design strategies for scaffolding were applied) showed higher levels of achievement than those who used the original version. In addition, students in the experimental group generally showed higher scores on the usability survey, which consisted of four sub-categories such as 'effectiveness', 'efficiency', 'satisfaction', and 'learnability'. There was a statistically significant effect on 'efficiency'. These results implied that scaffolding strategies were effective for mathematics learning through the use of an elementary digital textbook.

• International Journal of Air-Conditioning and Refrigeration
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• v.11 no.2
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• pp.67-72
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• 2003

A partition integrated air supply system can provide highly personalized environmental control. The supply air is brought up through raised floors and supplied to outlets located on the partition panels. The purpose of this paper is to find out the best design of outlets for optimal occupant comfort within a personal task area. Real scale experiments were conducted to allow for comparisons of outlet designs within a personal task area. Experimental results indicate that the location of an outlet is the most critical factor in improving the efficiency of supply air distribution of a personal task area. Thermal characteristic comparisons were made between the under-floor and the partition supply systems. Experimental results suggest that the partition supply system is more efficient than the under-floor supply system in terms of cooling. Such a system allows occupants to personally control their immediate environment, resulting in higher productivity.

• Computers and Concrete
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• v.26 no.4
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• pp.351-365
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• 2020

This work presents numerical and experimental analyses of the behavior of reinforced-concrete deep beams with unconventional geometries. The main goal here is to experimentally and numerically study these geometries to find possible new behaviors due to the material nonlinearity of reinforced concrete with complex geometries. Usually, unconventional geometries result from innovative designs; in general, studies of reinforced concrete structures are performed only on conventional members such as beams, columns, and labs. To achieve the goal, four reinforced-concrete deep beams with geometries not addressed in the literature were tested. The models were numerically analyzed with the Adaptive Micro Truss Model (AMTM), which is the proposed method, to address new geometries. This work also studied the main parameters of the constitutive model of concrete based on a statistical analysis of the finite element (FE) results. To estimate the ultimate loads, FE simulations were performed using the Monte Carlo method. Based on the obtained ultimate loads, a probabilistic distribution was created, and the final ultimate loads were computed.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.581-586
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• 2003

This paper presents control designs using neural networks (NN) for a XY positioning table. The proposed neurocontroller is composed of an outer PD tracking loop for stabilization of the fast flexible-mode dynamics and an NN inner loop used to compensate for the system nonlinearities. A tuning algorithm is given for the NN weights, so that the NN compensation scheme becomes adaptive, guaranteeing small tracking errors and bounded weight estimates. Formal nonlinear stability proofs are given to show that the tracking error is small. The proposed neuro-controller is implemented and tested on an IBM PC-based XY positioning table, and is applicable to many precision XY tables. The algorithm, simulation, and experimental results are described. The experimental results are shown to be superior to those of conventional control.