• Journal of the Korea Concrete Institute
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• v.14 no.3
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• pp.373-381
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• 2002

The cost on transmission and erection of the precast prestressed concrete members largely depends on the weight of them. Optimum process is performed on a U-beam section to control the prestressing force, to reduce the self-weight, and to meet the required strength and stability. The strength, deflection, and concrete stress at the top and bottom of the section considered are required to check according to each construction step in this process. The weight of the original rectangular concrete beam could be reduced up to 39∼50％ from this method. Two full scale prototype U-beams were proposed and tested in this study. It was found that the U-beams in the test showed good performance in strength and serviceability within the limits of ultimate strength design method.

• Smart Structures and Systems
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• v.21 no.2
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• pp.171-185
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• 2018

Maintenance of deteriorated bridge structures has always been one of the challenging issues in developing countries as it is directly related to daily life of people including trade and economy. An effective maintenance strategy is highly dependent on timely inspections on the bridge health condition. This study is intended to investigate an approach for detecting bridge damage for the long-term health monitoring by use of copula theory. Long-term measured data for the seven-span plate-Gerber bridge is investigated. Autoregressive time series models constructed for the observed accelerations taken from the bridge are utilized for the computation of damage indicator for the bridge. The copula model is used to analyze the statistical changes associated with the modal parameters. The changes in the modal parameters with the time are identified by the copula statistical properties. Applicability of the proposed method is also discussed based on a comparison study among other approaches.

• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.1
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• pp.119-131
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• 2014

The phenomenon of cavitation is an unsteady flow, which is nearly inevitable in pump. It would degrade the pump performance, produce vibration and noise and even damage the pump. Hence, to improve accuracy of the numerical prediction of the pump cavitation performance is much desirable. In the present work, a homogenous model, the Zwart-Gerber-Belamri cavitation model, is considered to investigate the influence of the empirical coefficients on predicting the pump cavitation performance, concerning a centrifugal pump. Three coefficients are analyzed, namely the nucleation site radius, evaporation and condensation coefficients. Also, the experiments are carried out to validate the numerical simulations. The results indicate that, to get a precise prediction, the approaches of declining the initial bubble radius, the condensation coefficient or increasing the evaporation coefficient are all feasible, especially for declining the condensation coefficient, which is the most effective way.

• International Journal of Naval Architecture and Ocean Engineering
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• v.13 no.1
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• pp.450-465
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• 2021

In this study, an attempt has been made to investigate the water-entry characteristics of the high-speed parallel projectile numerically. The shear stress transport k-𝜔 turbulence model and the Zwart-Gerber-Belamri cavitation model based on the Reynolds-Averaged Navier-Stokes method were used. The grid independent inspection and grid convergence index is carried out and verified. The influences of the parallel water-entry on flow filed characteristics, trajectory stability and drag reduction performance for different values of initial water-entry speed (𝜈₀ = 280 m/s, 340 m/s, 400 m/s) and clearance between the parallel projectiles (L_p = 0.5D, 1.0D, 2.0D, 3.0D) are presented and analyzed in detail. Under the condition of the parallel water-entry, it can be found that due to the intense interference between the parallel projectiles, the distribution of cavity is non-uniform and part of the projectile is exposed to water, resulting in the destruction of the cavity structure and the decline of trajectory stability. In addition, the parallel projectile suffers more severe lateral force that separates the two projectiles. The drag reduction performance is impacted and the velocity attenuation is accelerated as the clearance between the parallel projectiles reduces.

• Journal of the Korea institute for structural maintenance and inspection
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• v.8 no.2
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• pp.137-145
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• 2004

The paper provides a methodology of identifying a substructure model when sectional and material properties of the structure are not the a priori information. In defining a substructure model, it is required that structural responses be consistent with the actual behavior of the part of the structure. Substructure model is identified by estimating boundary spring constants and stiffness properties of the substructure. Static and modal system identification methods have been applied using responses measured at limited locations within the substructure. Simulation studies for static and dynamic responses have been carried. The results and associated problems are discussed in the paper. The procedure has been also applied to an actual multi-span plate-girder Gerber-type bridge with dynamic responses obtained from a moving truck test and construction blasting vibrations.

• Korean Journal of Food Science and Technology
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• v.20 no.5
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• pp.683-690
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• 1988

This study was conducted to determine the organoleptic and physical properties and carotenoid of commercial canned, frozen and freshly-made carrot juice. Samples were evaluated by sensory panel and measured for viscosity and acidity. For carotene analysis, HPLC of alpha- and beta-carotene, and spectrophotometry of total carotenoid content were used. Sensory evaluation indicated that the canned sample was less acceptable, especially for flavor and texture, than other juices, while forzen juice was considered as acceptable as freshly-made carrot juice. The canned product showed about 10 times higher viscosity and lower acidity than others. Between two kinds of frozen samples, one sample was the same as freshly-made sample for all parameters while the other showed less alpha-carotene content which was 2 times higher than that of canned one. Canned sample contained 70-77% of freshly-made or frozen samples in total carotenoid and beta-carotene content and 24% of freshly-made one in alpha-carotene. These results suggest that freezing process is a good preservation method for carrot juice with respect to sensory evaluation, physical property and carotenoid content.

• Fashion & Textile Research Journal
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• v.18 no.6
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• pp.746-754
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• 2016

This study aimed to investigate the status of ready-made suit and MTM (Made-to-measure) suit production with 10 men's suit brands turning over 200 billion won. Their target age group is late 30's to late 40's. Regarding production for the ready-made suit, eight out of 10 brands are using both KS and their own sizing. Classification of body shapes was done in 8 brands, mostly for upper body in simple ways (lean, normal, and obese). All brands are conducting fittings on only standard size. The number of sizes produced is varying depending on the brands; 9 to 17 for a jacket and 9 to 20 for a pair of pants. Regarding on the MTM production, four out of 10 brands have implemented MTM production. The rate of MTM production to their total production is about 15-20%. There were positive opinions on MTM production since it enables to reduce stocks through a small quantity of production for necessary sizes only. The reasons of orders of MTM production were answered as 'no size available', 'unique body shape', etc., and most orders were placed by consumers who are fat-bellied or have thick thighs. They have used MTM automated CAD software developed by Gerber Technology or Investronica. All the brands have utilized automated marker-making software and cutting facilities for MTM production.

• Journal of Families and Better Life
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• v.32 no.5
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• pp.193-205
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• 2014

The purpose of this research is to gather basic data to make nursery teachers' role clear and to suggest a way to improve their expertise by investigating their sensitivity and expertise. To fulfill this aim, this research was performed by targeting 180 nursery teachers responsible for infant classes in national, public, and private nursery schools. To measure the nursery teachers' sensitivity, Gerber's (2003) teacher sensitivity indicator is used. And to measure the efficacy of teaching play, the indicator, which was developed by E. Shin, Y. Yu and H. Park (2004), was used through modification and complement. Also for measuring the teacher's expertise, research data were collected by the generalized and modified questionnaire which was used in H. Yoon's (2010) research. The results of the analysis of collected data show that the teacher group with higher sensitivity in the infant class shows meaningfully higher professional ethics, higher performance, and higher recognition of expertise than the teacher group with lower sensitivity. And the teacher group with higher awareness of the efficacy of play shows higher professional ethics, higher performance, and higher recognition of expertise than the teacher group with lower sensitivity. too. Also, the results of the analysis of the correlation between the infant teacher's sensitivity, efficacy of teaching play, and recognition of expertise show that the teacher's sensitivity has a static correlation with the total points of social necessity, professional ethics, fairness, teacher's performance, and recognition of expertise. When we generalize the research results, we find that positive sensitivity and higher efficacy of teaching play make the infant class teacher's expertise recognition higher.

• The Research Journal of the Costume Culture
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• v.10 no.5
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• pp.542-554
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• 2002

The purposes of this study were to investigate, analyze, and consider the feature and practical situation of Apparel CAD education and distribution situation of CAD system so that CAD education can be effectively operated and managed in various kinds of relevant schools and universities. 32 colleges and universities that are performing CAD educational system are selected for the study. The author of the study has investigated and obtained the information through questionnaires to 32 professors who are in charge of CAD lectures and 301 students who are receiving CAD education. The result is as follows. 1. It showed that 62.5% of CAD educational systems have been practically introduced after 1995. Regarding the using system, YUKA occupies 46.9%, PAD 21.8%, and GERBER 18.8% and these three kinds of system have been chiefly supplied. 40.6% of them own only one system, 37.5% of them own 2～5 systems and 78% of them own less than 5 systems. 2. The most seriously pointed problems during the operation of CAD system were the lack of experimental materials and the frustration of manpower supply. Thus, the CAD education programs in schools and universities are practiced in inferior environments internally and externally. 3. Regarding the practical situation of CAD education, 28 among 32 schools and universities are performing CAD as one of the regular subjects for the curriculum. 4. Regarding satisfaction degree of the using system, professors showed higher satisfaction degree than students did. In conclusion, it showed that although the practical situations of CAD education in schools and universities have been changed and improved so much since 1995 owing to the increase of the positive recognition of the necessity of CAD, many students in the educational sites cannot study their favorite subjects related with CAD program with interest due to the lack of experimental facilities, the poor computer management systems, and the problems of manpower supply, etc.

• The Research Journal of the Costume Culture
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• v.11 no.6
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• pp.835-851
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• 2003

This study analyses patent information of apparel design using computer technology and researches the trend of patent application focused on International Patent Classification. In terms of trend by filling data, Patent application started first in 1974 and increased sharply in 1993 with 14 cases and increased to 25 cases in 2000. In case of Korea, they began somewhat late in 1996, but reached a similar level with the leading country in 2000. In terms of trend by applicant, Gerber Garment Technology, Inc. filed 7 cases TORAY IND INC, filed 6 cases Levi Strauss & Co. filed 4 cases, NEC HOME ELECTRONICS LTD filed 3 cases, TOYOBO CO LTD filed 3 cases. Japanese companies occupied 52% and United States's companies occupied 48%. In terms of trend by country, foreigner occupied 47% of the patents filed by United State. Japanese take up 10% of total patent of United States. Korean occupied 84% of total patent of Korea and foreigner, american occupied 16% of the patents filed by Korea. In regared to International Patent Classification, in the section level G filed 92 cases(53%). In class level, G06 marked the first place in United States, Japan, and Korea. In subclass level, G06F marksed the first place with 74 cases. G06T and A61B were regarded as the new technologies. The new technologies are representing the dimensions of garment or computer-rendered model, providing the virtual reality through the texture mapping, digital dressing room or virtual dressing, and performing or retriving display on a screen for the result of changing pattern ao dress design, The technologies of core patent are designing or producing custom manufactured item, providing or prealtering the data for pattern making and visually displaying, interactively generating or previewing of various articles.