• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.400-402
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• 2007

This paper presents a vector control implementation for PMSM using Real Time Workshop and Embedded Target for TI C2000 DSP in MATLAB/SIMULINK. Speed, current and vector controllers are easily designed and implemented by using the MATLAB/SIMULINK program. Feedback of motor speed is processed through C28x QEP(Quadrature Encoder Pulse) block from encoder pulse. 3-Phase currents ares processed through C28x ADC block from current sensors. And gating signal of PWM inverter is generated through SVPWM and PWM block. Real-time program is drawn using SIMULINK and then converted program code for speed control of PMSM is downloaded into the TI eZdsp 2812 board. Experiments were carried out to examine validity of the proposed vector control implementation.

• Proceedings of the Korea Concrete Institute Conference
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• 1994.10a
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• pp.261-266
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• 1994

The objective of this study is to develop the expert system for R/C box culvert design. This program provided various functions to improve automatic design. The program is composed of five steps. The characteristics of each step are as follows; 1) Preprocessing Step, 2) Analysis Step, 3) View of Memberforce Step, 4) Postprocessing Step, 5) Printing of Design-Sheet Step. Finally, Expert System and Knowledge Database System is developed for the drawing of optimal R/C box-culvert design.

• Journal of Electrochemical Science and Technology
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• v.12 no.1
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• pp.137-145
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• 2021

Among the non-precious metal catalysts, iron-nitrogen doped carbon (Fe-N/C) catalysts have been recognized as the most promising candidates for an alternative to Pt-based catalysts for the oxygen reduction reaction (ORR) under alkaline and acidic conditions. In this study, the nano replication method using mesoporous silica, which features tunable primary particle sizes and shape, is employed to prepare the mesoporous Fe-N/C catalysts with different shapes. Platelet SBA-15, irregular KIT-6, and spherical silica particle (SSP) were selected as a template to generate three different kinds of shapes of the mesoporous Fe-N/C catalyst. Physicochemical properties of mesoporous Fe-N/C catalysts are characterized by using small-angle X-ray diffraction, nitrogen adsorption-desorption isotherms, and scanning electron microscopy images. According to the electrochemical evaluation, there is no morphological preference of mesoporous Fe-N/C catalysts toward the ORR activity with half-cell configuration under alkaline electrolyte. By implementing X-ray photoelectron spectroscopy analysis of Fe and N atoms in the mesoporous Fe-N/C catalysts, it is possible to verify that the activity towards ORR highly depends on the portions of "Fe-N" species in the catalysts regardless of the shape of catalysts. It was suggested that active site distribution in the Fe-N/C is one important factor towards ORR activity.

• The Bulletin of The Korean Astronomical Society
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• v.25 no.2
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• pp.82-82
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• 2000

• Bulletin of the Korean Space Science Society
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• 2000.10a
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• pp.82-82
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• 2000

No Abstract, See Full Text

• The Journal of Korean Institute for Practical Engineering Education
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• v.3 no.2
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• pp.83-92
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• 2011

The computer program for analysis of mechanical vibration has been developed using visual C++. This program is organized in a format similar to most standard texts on the mechanical vibration. This program consists of a number of menus to perform various calculations as well as a set of dedicated graphical user interfaces. Solutions to problems are given in both graphical and numerical forms. Numerical examples show the effectiveness and applicability of the program. This program can be utilized to analyze the vibration behavior of mechanical systems.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2001.10a
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• pp.219-226
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• 2001

In general, engineers have to consider a variety of factors in design of a structure. For this reason, it was difficult to make a design program up to now. But the rapid development of hardware and software turns it into a possibile one with considering complex factors and designing simple structures. When we use the design program including structural analysis, we can save time and cost to make calculations; report and drawing. In addition, the design program was developed to reduce the man made errors. Therefore, in this study, we try to develope the design program of the superstructure of P.S.C girder bridge and abutment. This program will provide engineers with time that they can spend on a creative and efficiency task for development of design.

• Korean Journal of Materials Research
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• v.27 no.2
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• pp.119-126
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• 2017

WC-CrC-Ni coatings were prepared by nine processes of the Taguchi program with three levels for the four spray parameters: spray distance, flow rates of hydrogen and oxygen, and powder feed rate. The optimal coating process (OCP) was oxygen flow rate of 38 FMR, hydrogen flow rate of 53 FMR, powder feed rate of 25 g/min, and spray distance of 7 inches. Hardness of 1150 Hv and porosity of 1.2 %, were obtained by OCP; these are better results compared with the highest 1033 Hv and the lowest 1.5 % porosity obtained by nine processes of the Taguchi program. Friction coefficient of the WC-CrC-Ni coating decreased from $0.36{\pm}0.07$ at $25^{\circ}C$ to $0.23{\pm}0.07$ at $450^{\circ}C$. These values were smaller than those of the EHC (electrolytic hard chrome) plating at both temperatures due to lubrication from the oxide debris. The wear trace and wear depth of the coating are smaller than those of the EHC at both temperatures. Pitting was not found in the WC-CrC-Ni coating sample, while it did appear in the EHC sample.

• Journal of The Korean Society of Integrative Medicine
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• v.9 no.3
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• pp.9-18
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• 2021

Purpose : In this study, we applied a computerized cognitive rehabilitation program (CoTras-C) for children with cerebral palsy. Research was conducted to investigate the impact of upper limb function, sensory function, and activities of daily living. Methods : The study period lasted 10 weeks from October 2019 to December 2019. The study subjects were 12 subjects according to the selection criteria, and a computerized cognitive rehabilitation program (CoTras-C) was conducted twice a week for 30 minutes before and after the application of basic occupational therapy. Results : As a result of the computerized cognitive rehabilitation program, scores of upper limb function (QUEST), sensory function (SSP-2), and daily life activity (WeeFIM) were significantly improved (p>.05). From the result of examining the motor area, improvement in fine-motor function and protective extension through touch pad or controller operation was found. It also showed improvement in activities of daily living including motor and activities of daily living including social cognition. In the sensory function evaluation, it was not significant in movement sensitivity. Significant differences were shown in the items excluding olfactory/taste sensitivity. Conclusion : The application of the computerized cognitive rehabilitation program (CoTras-C) showed significant results in upper limb function, sensory function, and daily life activities of children with brain lesions. Based on these results, future studies need to generalize the study by expanding the age or population of children with brain lesions, or by expanding the diversity of diseases and environments.

• Research in Community and Public Health Nursing
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• v.18 no.4
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• pp.535-542
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• 2007

Purpose: The purpose of this study was to identify the effects of an overweight control exercise program on body composition and blood lipids. Method: This comparative study was conducted at an elementary school in Seoul, Korea. Pre and post body weight, BMI, PBF, and obesity degree as body composition and TC, HDL-C, LDL-C, and TG as blood lipids were tested. The aerobic exercise lasted 12 weeks from April to July, 2006. A total of 168 overweight 3rd grade to 5th grade school children attended and were divided into a walking exercise group (n=68) and a rope jumping exercise group (n=38). Data were analysed using SAS 8.12. Result: At the end of the program, the participation rate was higher in the rope jumping exercise group than in the walking exercise group. Body weight, BMI, PBF, obesity degree, TC, and LDL-C were lower than those before the program, and HDL-C was higher than before the program. Conclusion: The school-based overweight control exercise program was effective. Because of the participation rate was higher in the rope jumping exercise group than in the walking exercise group, rope jumping exercise is recommended for low grade children.