• Journal of the Korean Society for Precision Engineering
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• v.20 no.8
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• pp.115-125
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• 2003

To analyze the applications of all types of mechanical systems, general purpose analysis programs have been developed and commercialized. However, it is customary to develop and use customized programs even though they sometimes require more work than a general purpose program. A customized program is simplified to adapt to a particular application from the beginning, is designed for small computers, and developed with hardware-in-the-loop in mind so it can be applied effectively. By adding design knowledge and bundling know-how to an analysis program, analysis time can be reduced. And because an analysis has to work in conjunction with other analysis programs, a proprietary program that the user can easily modify can be useful. In this thesis, a multi-body dynamics analysis system is presented using one of the most useful programming techniques, object-oriented concept. The object-oriented concept defines a problem from the physical world as an abstract object, an abstract model. The object becomes encapsulated with the data and method. Simulation is performed using the object's interface. It is then possible for the user and the developer to modify and upgrade the program without having particular knowledge of the analysis program. The method presented in this thesis has the following advantages. Since the mechanical components of the multi-body system converts independent modeling into a class, the modification, exchange, distribution, and reuse of elements are increased. It becomes easier to employ a new analysis method and interface with other S/W and H/W systems. To employ a new analysis method, there is no need to modify elements of the main solver and the Library. In addition, information can be communicated to each object through messaging. It makes the modeling of new elements easier using inheritance. When developing a S/W for the computer simulation of physical system, it is reasonable to use object-oriented modeling. Also, for multi-body dynamics analysis, it is possible to develop a solver that is user-oriented.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.6
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• pp.71-77
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• 2014

Despite the ubiquity of electronic media, paper is still the most generally readable carrier of information. Because paper materials are deteriorated by chemical, biological and physical factors over time, there have been major concerns about the decay of large collections of books, publications, old maps, historical artifacts, and written records. Therefore, manufacture of permanent paper has been a highly debated issue in paper conservation research. Through the use of permanent paper, our new records, journals, library books, art works, and all culturally and historically important documents can be preserved. In this study, handsheets were made of mixture of hemp bast fiber produced by soda pulping and HwBKP varying the amount of hemp. Physical, mechanical and optical properties of each handsheet were examined. As the ratio of hemp bast fiber increased, mechanical properties were improved significantly, but opacity decreased. After aging, the optical properties of the handsheets mixed with the hemp bast fiber more decreased than those of the non-mixed handsheet. The more mixture ratio of hemp bast fiber increased, the more decreasing rate of optical properties increased. As a result, it was confirmed that hemp bast fiber is a very promising resource for the manufacturing of permanent paper.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.11C
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• pp.940-948
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• 2008

This paper presents a low-power, low-complexity design and implementation results of a high speed multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) wireless LAN (WLAN) baseband processor. The proposed processor is composed of the physical layer convergence procedure (PLCP) processor and physical medium dependent (PMD) processor, which have been optimized to have low-power and reduced-complexity architecture. It was designed in a hardware description language (HDL) and synthesized to gate-level circuits using 0.18um CMOS standard cell library. As a result, the proposed TX-PLCP processor reduced the power consumption by as much as 81% over the bit-level operation architecture. Also, the proposed MIMO symbol detector reduced the hardware complexity by 18% over the conventional SQRD-based architecture with division circuits and square root operations.

• Journal of Information Management
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• v.30 no.1
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• pp.48-67
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• 1999

In an advanced computer and information network technologies, users are rapidly approaching environment in which information will be created, delivered, managed and stored, using vastly different methods to traditional pap r based systems. Information seeking behavior contains not only physical access, but also cognitive process in which reading, viewing, analyzing, reasoning etc. The most Important factor determining the usability of electronic documents is cognitive process. But, currently Navigation tools for using electronic documents depend on physical searching without considering cognitive process. Therefore, this study examined feasibility of using overal cognitive process in developing navigation tools. Six cognitive process style have been analyzed to find common skill of information seeking process. Also this study suggests skills that needs to introduce to functions of navigation tool, such as searching, filtering, visualization, traversal, content structure.

• Journal of Korean Public Health Nursing
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• v.32 no.3
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• pp.451-467
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• 2018

Purpose: The aim of this study was to determine the related factors for psychological crises in Korean middle aged adults. Methods: RISS, KISS, National Assembly Digital Library, CINAHL, and PubMed were searched for relevant articles published until October 3, 2016. Finally, a total of 23 studies were included. Meta-analysis of the studies was conducted using Comprehensive Meta-Analysis 3.0 software to calculate the effect size. Results: The related variables of psychological crisis were categorized into 23 variables and 5 factor groups. The effects size (ES) of the overall defensive variables was -0.28. In the defensive factors, the psychological factor (ES=-0.67), followed by cognitive and behavioral factor (ES=-0.34), physical factor (ES=-0.31), and social relational factor (ES=-0.29) had the greatest effect on psychological crises. The effects size of the overall risk variables was 0.48. In the risk factors, the physical factor (ES=0.61) had the greatest effect on psychological crises, followed by the psychological factor (ES=0.53), and cognitive and behavioral factor (ES=0.10). Conclusion: An intervention program is needed to strengthen the defensive factors and reduce the risk factors for psychological crises of Korean middle aged adults.

• PNF and Movement
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• v.21 no.1
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• pp.1-10
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• 2023

Purpose: This systematic review aims to determine whether robot-assisted training is more effective in gait training for persons with subacute hemiparetic stroke. Methods: This study adopted a systematic review study design focused on subacute hemiparetic stroke, and four core academic databases were searched until June 11, 2021, for relevant studies, including PubMed, Embase, the Cochrane Library, and ProQuest Central. The review included randomized controlled trials (RCTs) evaluating the effects of robotic-assisted training on gait performance in persons with a diagnosis of subacute hemiparetic stroke. The selected RCT studies were qualitatively synthesized based on the population, intervention, comparison, outcome, settings, and study design (PICOS-SD). Results: The study selected five RCTs involving 253 subacute hemiparetic stroke patients and performing robotic-assisted gait training using the following devices: the Lokomat, Morning Walk, Walkbot, ProStep Plus, or Gait Trainer II. Five RCTs were eligible for the meta-analysis after quantitative synthesis, and the results showed that the robot-assisted gait training group had a greater gait performance than the control group based on the 10-meter walk test, Berg balance scale, Rivermed mobility index, functional ambulation category, and modified Barthel index. Conclusion: The results of this study showed that the gait performance of subacute hemiparetic stroke patients changes throughout robot-assisted gait training, but there were no indications that any of the clinically relevant effects of robot-assisted training are greater than those of conventional gait training. Further, the small sample size and different therapeutic intensities indicate that definitive conclusions could not be made.

• Journal of Korean Medicine Rehabilitation
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• v.34 no.1
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• pp.83-95
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• 2024

Objectives This review was conducted to evaluate the therapeutic effects of manual acupuncture (MA) for shoulder impingement syndrome (SIS). Methods We searched 12 electronic databases (DBpia, Korean studies Information Service System [KISS], Oriental Medicine Advanced Searching Integrated System [OASIS], Research Information Sharing Service [RISS], China National Knowledge Infrastructure [CNKI], CINAHL, Clinical Key, Cochrane Library, Embase, JAMA, PubMed, Web of Science) to find randomized-controlled clinical trials (RCTs) investigating therapeutic effects of MA for treating SIS. Shoulder Pain and Disability Index scores and numeric pain rating scale or visual analogue scale were analyzed as the main evaluation criteria. Results Among 181 studies, 169 were screened and only 12 RCTs were eligible in our review. Finally, 11 RCTs could be statistically analyzed. MA was more effective than sham treatment and physical therapy in terms of reducing pain (p=0.003, p=0.0007 each). Electroacupuncture (EA) showed more significant effect than physical therapy (PT) for improving shoulder pain (p<0.00001) and shoulder functionality (p<0.00001). Conclusions These results suggest that MA and EA could be superior option for treating SIS than sham treatment or PT. However this review has its limitations due to the small sample size and lack of well-designed RCTs that were included in the study. Further well-designed RCTs are necessary to provide high-level evidence.

• Journal of Astronomy and Space Sciences
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• v.25 no.2
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• pp.199-226
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• 2008

We investigate astronomical materials listed in the book of Bibliographie Coreenne written by Maurice Courant. He classified ancient Korean books into nine Divisions (部) and thirty six Classes (類), and published them as three volumes (ranging from 1894 to 1896) and one supplement (in 1901). In total, 3,821 books including astronomical ones are listed together with information on physical size, possessional place, bibliographical note, and so forth. Although this book is an essential one in the field of Korea bibliography and contains many astronomical materials such as Cheon-Mun-Ryu-Cho 天文類抄, Si-Heon-Seo 時憲書, and Cheon-Sang-Yeol-Cha-Bun-Ya-Ji-Do 天象列次分野之圖, it has not been well known to the public nor to astronomical society. Of 3,821 catalogues, we found that about 50 Items (種) are related to astronomy or astrology, and verified that most of them are located in the Kyujanggak Royal Library 奎章閣. We also found an unknown astronomical chart, Hon-Cheon-Chong-Seong-Yeol-Cha-Bun-Ya-Ji-Do 渾天總星列次分野之圖. Because those astronomical materials are not well known to international astronomical community and there have been few studies on the materials in Korea, we here introduce and review them, particularly with the astronomical viewpoint.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2006.11a
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• pp.202-207
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• 2006

This study was to find out users' satisfaction on the dormitory high school in Jeonju City and to propose it's physical environmental improvement directions. This was performed by a questionnaire survey method, and the questionnaire was designed by researchers considering relative literatures. Data were collected from 200 students, who had been dwelling 4 high school dormitories in Jeonju City. By analyzing those data, findings were as follows : 1) Users of students were satisfied the whole of their dormitory; facilities, spaces, and living. 2) They were highly concerned about a library and a personal unit space in their dormitory. 3) They needed their personal unit space to be designed bedroom+bathroom type with 2 persons' sharing and be equipped one story bed and desk furniture. Also, they needed improvement on heating & cooling, small space and indoor air quality of unit space. 4) The users' satisfaction on unit space were 3.23, and the space utility and the space size of functional factor and the heating/ventilation of technical factor were highly effected their satisfaction.

• Structural Engineering and Mechanics
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• v.32 no.5
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• pp.667-683
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• 2009

FE model-based dynamic analysis has been widely used to predict the dynamic characteristics of civil structures. In a physical point of view, an FE model is unavoidably different from the actual structure as being formulated based on extremely idealized engineering drawings and design data. The conventional model updating methods such as direct method and sensitivity-based parameter estimation are not flexible for model updating of complex and large structures. Thus, it is needed to develop a model updating method applicable to complex structures without restriction. The main objective of this paper is to present the model updating method based on the hybrid genetic algorithm (HGA) by combining the genetic algorithm as global optimization method and modified Nelder-Mead's Simplex method as local optimization method. This FE model updating method using HGA does not need the derivation of derivative function related to parameters and without application of complicated inverse analysis methods. In order to allow its application on diversified and complex structures, a commercial FEA tool is adopted to exploit previously developed element library and analysis algorithms. Moreover, an output-level objective function making use of measurement and analytical results is also presented to update simultaneously the stiffness and mass of the analysis model. The numerical examples demonstrated that the proposed method based on HGA is effective for the updating of the FE model of bridge structures.