• Journal of Biosystems Engineering
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• v.37 no.3
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• pp.155-165
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• 2012

This study was performed to offer the data for design of the seedling bed transfer equipment to make the automation of working process in a plant factory. The seedling bed transfer equipment pushing the seedling bed with bearing wheels on the rail for interconnecting each working process by a pneumatic cylinder was made and examined. The examined transfer force to push the seedling bed with a weight of 178.9 N by the pneumatic cylinder with length of 60 cm and section area of 5 $cm^2$ was measured by experiments. The examined transfer forces was compared with theoretical ones calculated by the theoretical formula derived from dynamic system analysis according to the number of the seedling bed and pushing speed of the pneumatic cylinder head at no load. The transfer function of the equipment with the input variable as the pushing speed $V_{h0}$(m/s) and the output variable as the transfer force f(t)(N) was represented as $F(s)=(V_{h0}/k)(s+B/M)/(s(s^2+Bs/M+1/(kM))$ where M(kg), k(m/N) and B(Ns/m) are the mass of the bed, the compression coefficient of the pneumatic cylinder and the dynamic friction coefficient between the seedling bed and the rail, respectively. The examined transfer force curves and the theoretical ones were represented similar wave forms as to use the theoretical formular to design the device for the seedling bed transfer. The condition of no vibration of the transfer force curve was $kB^2>4M$. The condition of transferring the bed by the repeatable impact and vibration force according to difference of transfer distance of the pneumatic cylinder head from that of the bed was as $Ce^{-\frac{3{\pi}D}{2\omega}}<-1$, where ${\omega}=\sqrt{\frac{1}{kM}-\frac{B^2}{4M^2}}$, $C=\{\frac{\frac{B}{2M}-\frac{1}{kB}}{\omega}\}$, $D=\frac{B}{2M}$. The examined mean peak transfer force represented 4 times of the stead state transfer force. Therefore it seemed that the transfer force of the pneumatic cylinder required for design of the push device was 4Bv where v is the pushing speed.

• Korean Institute of Interior Design Journal
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• v.27 no.2
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• pp.24-36
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• 2018

Implementing a home modification to enable elderly's safe and independent living is the key plan to realize their aging in place. South Korea in which had entered an aged society is not yet vitalized in home modification for the elderly compared to that of welfare-developed countries, and South Korea provides support that is limited to the low-income elderly. Therefore, this purpose of this study was to analyze the laws related to the home modification, the present condition of home modification support, the standards and guidelines in home modification, the support in house modification cost, and supporting organization and working force in the home modification. Through the analyzing process, this study examined the current situation and problems of institutional support in the home modification for elderly and the proposed plan for institutional improvement. The suggestions based on the results are as in the following. 1) Home modification support law(act or regulation) is required to be improved 2) Home modification support system correspondent to aging process should be provided regardless of their income levels. 3) Delicate plan standard and guideline are necessary for a process of implementing the home modification for the elderly. 4) Information on life behavior is in need for the implementation of elderly-customized home modification. 5) Cost for the home modification should be considered to cover by the Act on Long-Term Care Insurance for the Aged. 6) Housing Welfare Center and Housing Welfare Professional should be actively utilized for the home modification support institution and work force.

• Journal of Fashion Business
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• v.27 no.3
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• pp.63-74
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• 2023

As "Made in Korea" has high branding power in the fashion industry, domestic clothing manufacturers also need to consider branding the country of origin. Therefore, the purpose of this study was to reconsider the need for a domestic certification system and suggest a direction by analyzing apparel origin certification systems operating overseas. The results of this study could be used for planning certification standards and operating methods suitable for regional characteristics and industrial environments when establishing a certification system for clothing produced in Korea. The case study subjects were Japan's J∞ Quality, USA's Made in New York, Italy's 100% Made in Italy, and France's Origin France Guarantee has been classified as certification criteria related to the country of origin include items related to the production process rate in the region and the production area for each production process/stream. Manufacturing technology and design are used for quality standards, safety, hygiene compliance, production facilities, and quality control and are applied to working environment standards. The certification system selects and operates standards according to each country's industrial environment, certification subject, and purpose. Therefore, when designing a domestic apparel certification system, a feasible promotion plan should be established that considers the current state of the domestic industry, which will serve as a driving force for the growth of the apparel manufacturing industry and an opportunity to increase the trust of global fashion consumers.

• Wind and Structures
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• v.26 no.4
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• pp.191-204
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• 2018

This article presents a study of the largest-ever (height = 220 m) cooling tower using the large eddy simulation (LES) method. Information about fluid fields around the tower and 3D aerodynamic time history in full construction process were obtained, and the wind pressure distribution along the entire tower predicted by the developed model was compared with standard curves and measured curves to validate the effectiveness of the simulating method. Based on that, average wind pressure distribution and characteristics of fluid fields in the construction process of ultra-large cooling tower were investigated. The characteristics of fluid fields in full construction process and their working principles were investigated based on wind speeds and vorticities under different construction conditions. Then, time domain characteristics of ultra-large cooling towers in full construction process, including fluctuating wind loads, extreme wind loads, lift and drag coefficients, and relationship of measuring points, were studied and fitting formula of extreme wind load as a function of height was developed based on the nonlinear least square method. Additionally, the frequency domain characteristics of wind loads on the constructing tower, including wind pressure power spectrum at typical measuring points, lift and drag power spectrum, circumferential correlations between typical measuring points, and vertical correlations of lift coefficient and drag coefficient, were analyzed. The results revealed that the random characteristics of fluctuating wind loads, as well as corresponding extreme wind pressure and power spectra curves, varied significantly and in real time with the height of the constructing tower. This study provides references for design of wind loads during construction period of ultra-large cooling towers.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.10
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• pp.1146-1152
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• 2011

Ink transfer process is very important to determine quality of printed pattern, therefore its mechanism should be understood to control printing quality. Although there have been many attempts to understand ink transfer mechanism by numerical simulation and experimental studies, their model was too much simple to model realistic printing process and our understanding is not enough yet. In this paper we designed ink transfer visualization system to present flow visualization of ink transfer process for gravure offset printing. We considered rotational effect of blanket roll which is related with printing speed and used non-Newtonian fluid as working fluid such as Ag paste. For printing unit, cantilever-type blanket roll is used for convenient visualization of ink transfer. Serial images were captured continuously by using high-speed CMOS camera and long range microscope. We investigated the effects of various design parameters such as printing speed and pattern angle on the ink transfer process. We found more stretched ink filament for non-Newtonian fluid than Newtonian fluid. As increasing printing speed, length of stretched ink filament and height of break-up point are also increased. We also compared ink transfer process between CD and MD pattern and its relationship with ink transfer mechanism.

• Nuclear Engineering and Technology
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• v.54 no.5
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• pp.1674-1685
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• 2022

The ball valve is an important device in the pipeline transportation system of nuclear power plants. Its operational stability and safety directly affect the normal working of nuclear power plants. In this study, the transient numerical simulation of the opening and closing process of a ball valve was conducted on the basis of the flow interruption capability experiment of the ball valve by using the moving mesh method and inlet and outlet variable boundary conditions. The flow rate and pressure difference with time of the opening and closing process of the ball valve were studied. The internal flow characteristics of the ball valve under different relative openings were analyzed in conjunction with the typical back-step flow structure. Results show that the transient numerical results agree well with the experimental results. The internal flow characteristics of the ball valve are similar at the same opening during opening and closing process. At small opening, the spool and outlet channels easily form a back-step flow structure. The disappearance and generation of backflow vortices during opening and closing occur at 85% opening and 75% opening, respectively. With the decrease in opening degree, the difference in vortex core area in the flow channel of the ball valve spool in the opening and closing process gradually appears. The research results provide some reference value for the design and optimization of ball valves.

• Journal of Dental Rehabilitation and Applied Science
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• v.40 no.2
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• pp.72-81
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• 2024

Purpose: This study aimed to assess the marginal and internal fit of 3-unit monolithic zirconia fixed partial dentures (FPDs) fabricated via computer-aided design and computer-aided manufacturing (CAD/CAM) from solid working casts and removable die system. Materials and Methods: The tooth preparation protocol for a zirconia crown was executed on the mandibular right first premolar and mandibular right first molar, with the creation of a reference cast featuring an absent mandibular right second premolar. The reference cast was duplicated using polyvinyl siloxane impression, from which 20 working casts were fabricated following typical dental laboratory procedures. For comparative analysis, 10 FPDs were produced from a removable die system (RD group) and the remaining 10 FPDs from the solid working casts (S group). The casts were digitized using a dental desktop scanner to establish virtual casts and design the FPDs using CAD. The definitive 3-unit monolithic zirconia FPDs were fabricated via a CAM milling process. The seated FPDs on the reference cast underwent digital evaluation for marginal and internal fit. The Mann-Whitney U test was applied for statistical comparison between the two groups (α = 0.05). Results: The RD group showed significantly higher discrepancies in fit for both premolars and molars compared to the S group (P < 0.05), particularly in terms of marginal and occlusal gaps. Color mapping also highlighted more significant deviations in the RD group, especially in the marginal and occlusal regions. Conclusion: The study found that the discrepancies in marginal and occlusal fits of 3-unit monolithic zirconia FPDs were primarily associated with those fabricated using the removable die system. This indicates the significant impact of the fabrication method on the accuracy of FPDs.

• Korean Institute of Interior Design Journal
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• v.23 no.6
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• pp.51-59
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• 2014

Rem Koolhaas has pursued new architectural approaches breaking with conventional ones. Around the 1990s when large-scale projects occurred with the union of Europe ahead, Koolhaas recognized the limits to the existing methods for responding to such changes. Accordingly, he came to use design methods based on 'congestion' and 'void' as strategical alternatives, which became the moment for him to leap forward from the previous working sphere based in Europe to becoming an architect who would be commissioned a number of large-scale global projects. Therefore, this study intends to investigate his design methods which utilized congestion and void, and to derive spatial characteristics from the projects based on such methods. First of all, the study looked into the historical background, definition and process of congestion and the void as design methods, and analyzed his projects to which such methods were applied by classifying them into the following categories: 1) the void that removes a space of singularity; 2) the void that penetrates space while making a flow; and 3) the void that is formed by vertical extrusion. Then, the characteristics of architectural spaces made in this way were identified as 1)the single-body appearance made by congestion and the following types of space made by the void: 2) the non-uniformly shaped space that looks like floating; 3) the flexible space with various flows and directions; and 4) the space with virtual possibilities that embrace contingent events. This understanding of Rem Koolhaas's design methods which were attempted in various ways at his critical turning point will be the foundation to understand the overall world of his works.

• Journal of the Korean Society of Costume
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• v.60 no.7
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• pp.31-46
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• 2010

Fashion industry is faced with issues of raising the competitiveness of established designers recently. As well as the change of business system, the specialization of professionals in design team increases the needs of in-service training of fashion designers. But, the education programs of enterprise are generally focused on adaptability to the organization and harmony among men as an introduction level. Furthermore, there are few professional institutions that give an education to the working-level designers. Thus, this study aimed at development of specialized in-service training program that could educate established designers for more integrated thought to cope with rapid changes in the fashion field. Firstly, the theoretical study on the in-service training and changes of fashion environment had been studied through literature review. Then, the current state of in-service training of fashion enterprises and the courses for established designers in fashion institutions were analysed. Finally, a comprehensive framework of in-service training program for fashion designers has been established as a result of this study. The program was designed in accordance with the previous research which reached 4 different educational needs for in-service training: brand planning and management, understanding production, understanding practical fabrics & colors, computer program. The study went further to apply the program to each design group divided by career: new designer, junior designer, senior designer, design leader. This study also suggested evaluation process to confirm the effects.

• Korean Institute of Interior Design Journal
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• v.27 no.1
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• pp.140-155
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• 2018

In response to the development of IT technology in the 21st century and the advancement of the public human rights consciousness, it has become necessary to continuously evolve the office environments to support the changes of organizational structure and work methods of the police investigation departments. As a facility standard, continuous researches on standardized design space models and guidelines of the police investigation departments are needed. In respond to the organizational changes for the convenience of the working police investigators and the protection of the human rights of the visiting public, the environmental improvement projects for the office of the investigation department of the police stations are going on since 2014. In this study, analyzation and verification of the 3 cases of pilot projects for the improvement of police investigation departments would be done, based on the policy research project in 2014: 'the standard design direction of police officers for the protection of human rights and benefit of police investigation process.' The purpose of this study is, first of all, the actual situation survey for presenting the standard design space model and guidelines of investigation department of the police department. Secondly, the validation of the spatial model adequacy for for the past 3 years' case study of the police investigation department's environmental improvements by the application of standardized design space models and guidelines. The result of this study would be to enable the more effective police department investigation environment improvement policy by presenting the standard design space models and guidelines of the investigation departments of the police facilities.