• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1682-1686
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• 2004

A slit-flow apparatus with laser diffraction method has been developed with significant advances in ektacytometry design, operation and data analysis. In the slit-flow ektacytometry (or laser-diffractometry), the deformation of red blood cells subjected to continuously decreasing shear stress in slit flow is measured. A laser beam traverses a diluted blood suspension flowing through a slit and is diffracted by RBCs in the volume. The diffraction patterns are captured by a CCD-video camera, linked to a frame grabber integrated with a computer, while the differential pressure variation is measured by a pressure transducer. Both measurements of laser-diffraction image and pressure with respect to time enable to determine deformation index and the shear stress. The range of shear stress of 0 ${\sim}$ 35 Pa and measuring time is less than 2 min. When deforming under decreasing shear stress, RBCs change gradually from the prolate ellipsoid towards a circular biconcave morphology. The Deformation Index (DI) as a measure of RBC deformability is determined from an isointensity curve in the diffraction pattern using an ellipse-fitting program. The advantages of this design are simplicity, i.e., ease of operation and no moving parts, low cost, short operating time, and the disposable kit which is contacted with blood sample.

• Journal of the Korean Institute of Educational Facilities
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• v.24 no.4
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• pp.3-14
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• 2017

Since the education law was changed in 1997, schools for K-12 education are required to build a multi-purpose auditorium which accommodates auditorium and a gymnasium functions. Evaluation of the present status of multi-purpose auditoriums will provide a clear direction for improvements in planning and design stages. The purpose of this research identifies the current status and major drawbacks of the multi-purpose auditorium through applying a performance evaluation tool kit called the Advanced Building Quality Evaluation Techniques(ABQET) and Graphic Analysis of Quality Quotient (GAQQ). In addition, the research will provide future foundations for planning and design methods for a multi-purpose auditorium.

• Educational Technology International
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• v.9 no.2
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• pp.97-121
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• 2008

The purposes of the present study are to describe the design of mobile learning scenarios based on learning sciences theories, and to discuss implications for the future research in this area. To move beyond mere speculations about the abundant possibilities of mobile learning and to make real impact in K-12 school settings, it is critical to conduct school-based research grounded on the learning sciences theories. Towards this end, this paper describes school-based mobile learning projects conducted by a research team at the Learning Sciences Lab in Singapore, and then discusses the possibilities and challenges of mobile learning to further inform future research. Specifically, this paper explores the affordances of mobile technology, such as portability, connectivity and context-sensitivity, to design seamless learning scenarios that bridge formal and informal learning experiences. The authors present a framework for re-conceptualizing different types of learning based on physical settings and intentionality, and then describe two seamless learning scenarios, namely 3Rs and Chinatown Trail, which were implemented in one primary school in Singapore. In conclusion, the authors discuss the affordances of seamless mobile learning for enhancing one's lived experiences to build a living ecological relationship between the person and the environment, and how mobile technology can play a critical role for enabling such lived experiences.

• Journal of the Ergonomics Society of Korea
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• v.31 no.1
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• pp.109-116
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• 2012

Objective: The aim of this study is to present a solution to problems in the services provided by the general hospitals by creating a user-centric environment through analyzing the User Journey Map and the User Context. Background: The rapid growth in aging population and the monopolization of superior medical staffs by the general hospitals increased demand for the general hospitals in Korea. But, often services provided by the general hospitals are provider-centric and low quality. Method: This study examines problems in the services provided by the general hospitals by analyzing the User Journey Map through stakeholder interviews(contextual interviews) and on-site observation. Based on the contextual analysis of the user(i.e. the patient), this study proposes new and improved user-centric services to be provided by the general hospitals. Results: Ten new user-centric services proposed by this study are: (1) "Booklet on Success Story", (2) "FAQs by Doctor", (3) "Designated Nurse", (4) "Patient Interview Record Card", (5) "Close relationship between doctor & patient", (6) "Thank You Notice Board", (7) "Step by Step", (8) "Green Cap", (9) "Patient Kit", (10) "RFID Direction Display System". Conclusion: The service design for the general hospitals proposed by this study is an important case-study on improving the environment of the general hospitals from provider(medical staffs)-centric to user(patents and its family)-centric. Application: This study is expected to be used in various areas to improve existing system(products and/or services) to be more user-centric.

• Journal of Dental Rehabilitation and Applied Science
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• v.36 no.2
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• pp.128-137
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• 2020

Over the last 30 years, the use of chairside computer-aided design (CAD) and computer-aided manufacturing (CAM) systems has evolved and has become increasingly popular in dentistry. Although CAD/CAM restorations have been used in the anterior dentition, satisfying the esthetic requirements of clinicians and patients, where the restorations are limited to the chairside, remains a challenge. To reproduce multi-shades of CAD/CAM restorations in the clinic, a preliminary experiment to express several shades on A2 lithium disilicate (LS2) blocks using a staining kit was performed. After measurement of the CIE L^*a^*b^* value of specimens, it was compared with that of the commercial shade guide. This report presents two cases with individual customization of shade and surface characterization of the CAD/CAM restorations using predictable methods based on the preliminary experimental data. The anatomical shape of restoration was obtained from 'copy and paste technique' and 'mirror image acquisition technique'. All treatment procedures and fabrication of restorations performed in this report were executed in the clinic itself.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.8
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• pp.737-742
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• 2015

Course correction munition are a weapson system for precision attacks and are assembled by applying a ballistic control system to existing projectiles. The roll control system is a subsystem of the ballistic control system and is placed between the guidance and control units inside of the projectile, which undergoes a 5000g lateral acceleration. Thus, it is very important to design the system to endure this load. Many developed countries evaluate the performance and safety of course correction munitions' parts using live-fire gun launch tests or a soft recovery system. However, these methods are expensive and slow. Thus, in this study, we develop impact analysis model of the roll control system using CAE. We apply the code to simulate impact phenomenon and use Johnson-Cook material model for modeling the high strain rate effect on the materials. We also design bearings in detail to analyze their behavior and verify the reliability of CAE model through gas-gun impact tests of the roll control system.

• Journal of Computational Design and Engineering
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• v.3 no.4
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• pp.363-369
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• 2016

Cyber Physical System (CPS) and Internet of Things (IoT) are hot objects of interest as an extension of the embedded system. These interactive products and systems contain Mobile Devices which are most popular and used most frequently. Also these have been widely used from the control of the Nuclear Power Control System (NPCS) to IoT Home Service. Information & Communication Technology (ICT) topics of trend fused-complex current Information Technology (IT) and Communication Technology (CT) are closely linked to real space and virtual space. This immediately means the arrival of the ultra-connected society. It refers to a society in which various objects surrounding the human innovation and change in the social sector are expected through the connection between the data which are to be generated. In addition, studies of Tool-kit for the design of such systems are also actively pursued. However, only increased cooperation and information sharing between the physical object consists of a variety of machinery and equipment. We have taken into consideration a number of design variables of the high barriers to entry about the product. In this study, It has been developed a Web-based collaboration framework which can be a flexible connection between macroscopically virtual environment and the physical environment. This framework is able to verifiy and manage physical environments. Also it can resolve the bottlenecks encountered during the base expansion and development process of IoT (Internet of Things) environment.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.9
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• pp.752-759
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• 2012

This paper presents a mission orbit design method for spacecraft which use the sun-synchronous and ground repeat orbits. In this work, we have proposed a new design procedure, "Nonlinear simulation-based numerical optimization technique" using the commercial S/W's such as STK (Satellite Tool kit) and Matlab, which are widely adopted S/W's in the area of orbital mechanics and engineering analysis. Inclusion of all the perturbation effects on the spacecraft not only can more precisely satisfy the mission requirements for sun-synchronicity and repeated ground track, and also operational requirements such as minimum change in the S/C local time, maximization of the contact time with a specified ground station, etc. can be appropriately considered. Design examples for LEO sun-synchronous mission are presented to demonstrate the usefulness of the proposed method in this paper.

• Journal of the Korean Home Economics Association
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• v.43 no.5 s.207
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• pp.235-248
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• 2005

The objective of the study was to design a Battle Dress Uniform(BDU with improved motional flexibility, body fit, and protectiveness to cope with the special operational environment of the subjects. For this purpose, the researcher conducted a questionnaire survey on 92 male members of Special Weapon Attack Team(SWAT units in a former study, and based on the results of the survey, made the two-piece and one- piece BDU samples to overcome the identified problems and inconveniences. The sample uniforms were designed ergonomically from five aspects. Subsequentlv, the new BDU was compared with the current operational uniform in terms of outward appearance(design and fit), motional flexibility, and suitability for field activities. The samples were evaluated by 5 SWAT members as subjects and 8 graduate school students majoring in clothing and textiles as experts. According to the results, the two-piece and one-piece samples gained higher scores than the existing operational uniform in terms of outward appearance(design and fitness) and motional flexibility, and the one-piece sample was preferred with regard to fit when worn by the subjects with their full kit for field operations. That is, the one-piece sample appeared to be more suited to the special work environment of SWAT and to be more functional in terms of ease of putting on and taking off, motional flexibility, body fit and protectiveness than the current operational uniform(two-piece type).

• Science of Emotion and Sensibility
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• v.10 no.3
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• pp.331-342
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• 2007

This study focused on developing MP3 smart clothing products and usability evaluation. MP3 smart clothing which was developed in this study contains e-textile keypad and a kit. The kit consists of MP3 Player, remote controller module and ear phone, and are easy to assemble and dismantle. And usability evaluation about MP3 smart Clothing which was developed in this study contains e-textile keypad and a kit. For making the MP3 Smart clothing, e-textile signal line and keypad was developed and a metal connection ring also was manufactured to adhere closely e-textile signal line to keypad. The last products are two kinds of MP3 smart clothing, jacket style of MP3-YSJ(Yonsei Smart Jacket) and safari style of MP3-YSS(Yonsei Smart Safari). Then usability evaluation conducted two times about MP3 smart clothing developed. Usability evaluation is classified by a module evaluation and an item evaluation. The module evaluation measured external appearance, material, a music controller, an ear phone(or a mini speaker) and connector. The item evaluation measured social acceptance, feeling of wearing, utility, easiness of maintenance and safety. The module evaluation described totally positive results in the first usability evaluation about MP3-YSJ 1.0 and MP3-YSS 1.0. The item evaluation shows a lower score in the social acceptance, especially the easiness of connector maintenance and the social acceptance of music-controller in MP3-YSJ 1.0 and MP3-YSS 1.0. The second usability evaluation conducted with improved products by the first usability test results. Results from second item evaluation indicated needs to improve the easiness of connector & music-controller maintenance and the social acceptance of music-controller in MP3-YSJ 2.0. In MP3-YSS 2.0, the easiness of material management and the social acceptance of music controller & connector needed to improvement. In particular, users felt inconvenience in the social acceptance because of e-textile keypad arrangement. To outweigh this disadvantage, further study is needed about keypad interface of the music controller.