• 소성∙가공
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• 제5권2호
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• pp.122-129
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• 1996

The main objective of the study is to offer some basic information in relation to optimal shape and dimensions of the rotating band through the development of three-dimensional finite element method for metal forming analysis of the rotating band whose primary function is to impart spin to the projectile. The three-dimensional metal forming analysis of the rotating band has perfor-med by using recurrent boundary conditions. Such design factors as the outside diameter the total length and the profile of the rotating band must be considered carefully in order to design an optimal rotating band. Above design factors can be determined from such available analysis results as the deformed shape and the deformation load. of the rotating band and the normal pressure of the rotating band on a projectile shell. The remeshings are needed to carry out plastic deformation analysis with severe deformation through which the complete process analysis gets possible. The results can be utilized effectively in determining the optimal shape and size of the rotating band.

• 대한원격탐사학회지
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• 제17권2호
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• pp.165-181
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• 2001

Using a field spectrometer having a spectral range of 0.4$\mu\textrm{m}$~2.5$\mu\textrm{m}$ with a spectral resolution of 1nm, the researchers measured the reflectance of granite, andesitic rocks, sedimentary rocks, and pyrophyllite ore in the Ungsang area, Kyungsang Basin, South Korea. Spectral characteristics of the geological media were investigated from the analysis. The in-situ measured sites were selected in well exposed rock outcrops. In case of unfavorable weather conditions, rocks were sampled and remeasured under natural solar condition. The reflectance of field data was measurd at three sistes for granite, six sites for andesitic rock three sites for sedimentary rocks, and two sites for pyrophyllite ore. The vibrational absorption bands for pyrophyllite are detected in the spectral range of 2.0$\mu\textrm{m}$~2.5$\mu\textrm{m}$. The absorption band for granites in study area is not distinctive. The reflectance measured under normal field conditions showed strong absorption at wavelengths of 1.4$\mu\textrm{m}$ and 1.9$\mu\textrm{m}$ due to the effect of moisture in the atmosphere. After the bands of 1.4$\mu\textrm{m}$ and 1.9$\mu\textrm{m}$ were removed, Hull Quotient method was applied to characterize absorption bands. The reflectances of field data were calculated to estimate the band ratio corresponding to the Landsat TM and EOS Terra ASTER. The researchers suggest here that the TM band2, band3, band4, and band7 or ASTER band2, band3, band4, and band9 are the best combination for discriminating outcrops. The researchers tested and demonstrated using a Landsat TM image in the study area. For geologic applications, decorrelation stretch is also an effective tool to enhance the exposed rock mass in images.

• Interaction and multiscale mechanics
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• 제6권1호
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• pp.15-29
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• 2013

Phononic system composed of periodical elastic structures exhibit band gap phenomenon, and all elastic wave cannot propagate within the band gap. In this article, we consider one-dimensional binary materials which are periodically arranged as a 20-layered medium instead of infinite layered system for phononic system. The layered medium with finite dimension is subjected to a uniformly distributed sinusoidal loading at the upper surface, and the bottom surface is assumed to be traction free. The transient wave propagation in the 20-layered medium is analyzed by Laplace transform technique. The analytical solutions are presented in the transform domain and the numerical Laplace inversion (Durbin's formula) is performed to obtain the transient response in time domain. The numerical results show that when a sinusoidal loading with a specific frequency within band gap is applied, stress response will be significantly decayed if the receiver is away from the source. However, when a sinusoidal force with frequency is out of band gap, the attenuation of the stress response is not obvious as that in the band gap.

• 대한화상학회지
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• 제23권1호
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• pp.25-29
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• 2020

This paper presents our clinical experiences for reconstruction of the linear depressed postburn scar band by rhombus subcutaneous pedicle skin flap (RSPF). We report new RSPF, it's versatility, and effectiveness for correction of the mild to moderate linear depressed postburn scar band. To correct the postburn scar band, we have newly designed the Rhombus Subcutaneous Pedicle Skin Flap (RSPF), which is made as rhombus-shaped skin flap on the inside of scar band. After excision of burn scar band, the each vertex of RSPF flap is advanced into the skin defects at apex of extended skin incision, which is starting from the upper and lower portion of the removed burn scar band at a near right angle. This flap can add more extra skin to adjacent superior and inferior area of excised scar band. We have experienced 2 cases of RSPF for reconstruction of linear depressed postburn scar band deformities in lower extremity. After 3 weeks to 3 months postoperative follow ups, relatively satisfactory results were obtained in all cases. We had successfully reconstructed the linear depressed postburn scar postburn band of lower extremity using the rhombus subcutaneous pedicle skin flap. For the correction of mild to moderate sized linear depressed postburn scar band deformities in extremity, the RSPF is simple, and very effective without donor morbidity.

• 한국전문물리치료학회지
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• 제29권4호
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• pp.274-281
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• 2022

Background: The range of motion (ROM) and balance ability of the ankle joint affect the stability of the ankle and prevent injuries or hurts from falling. In the clinical tests conducted recently, the floss band is widely used to enhance the range of joint motion and exercise performance, and there are many studies that have applied it to ankle joint increasing dorsi flexion (DF) angle. Objects: This study compared the effects on the range of ankle motion and static/dynamic balance ability of the ankle through three conditions (before floss band intervention, after floss band intervention, and after active exercise intervention) for adults. Methods: One intervention between floss band and active exercise was applied randomly and another intervention was applied the next day. After each intervention, the ROM of the ankle joints and the static balance was checked by measuring conducting one leg test. And the dynamic balance was checked by conducting a Y-balance test. Results: In the case of DF, the range of joint motion showed a significant increase after floss band intervention compared to before floss band intervention (p < 0.05). Static balance ability showed a significant increase after the intervention of floss band and active exercise compared to before the intervention of floss band (p < 0.05). The dynamic balance ability showed a significant increase after the intervention of the floss band compared to before intervention of the floss band and after active exercise intervention (p < 0.05). Conclusion: Based on these results, it was confirmed that the application of floss band to the ankle joint increases DF and improves the static and dynamic balance ability. Based on this fact, we propose the application of a floss band as an intervention method to improve the ROM of the ankle joint and improve the stability of the ankle in clinical field.

• Journal of electromagnetic engineering and science
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• 제6권2호
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• pp.98-102
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• 2006

In this paper, we have designed and fabricated the high power amplifier employing PBG(Photonic Band-Gap Structure) to improve the linearity of the amplifier in the millimeter wave band. The fabricated amplifier using MMIC(TGA1073G) has operated about 24 GHz band and the PBG has resulted in 35 dB suppression about 49 GHz where the second harmonic occurs due to the amplifier. As a result, the output power has been 24.43 dBm and 13.2 dBc of the IMD has been improved. Also, the PAE is obtained to 14.96 % of the amplifier employing the PBG structure in Ka band.

• 인터넷정보학회논문지
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• 제2권3호
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• pp.27-36
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• 2001

Recently much attention has been paid for interference mitigation technique for the COMA system, since more capacity is available with same bandwidth. In this paper, we introduces a novel adaptive interference suppression techniques for the CDMA system with narrow band interference. The proposed interference rejection scheme employs the adaptive linear prediction techniques in the subband. In each subband, we can more easily find and cancel the narrow band signal as compared to the full band. Thus, the proposed interference rejection can be classified as another time-frequency techniques for the narrow band interference rejection(10). Computer simulation is conducted for the 3-G COMA system with IF band sampling techniques, yielding better interference rejection and bit error rate performance as compared to conventional one. Also, optimum filter is analyzed and from the analysis, it can be shown the subband prediction techniques can suppress narrow band interference more efficiently.

• 한국전문물리치료학회지
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• 제4권3호
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• pp.17-33
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• 1997

The objective of this study was to identify pulmonary functional variations in relation to postural changes, lapse after changing position, and the use of abdominal band in the cervical cord injured. The subjects of this study were 19 quadriplegic patients who had been admitted to the department of the Rehabilitation Hospital, College of Medicine, Yousei University, from April, 1997 through May 3, 1997. A spiroanalyzer was used to measure pulmonary function in supine, standing, time after changing position, and recording to the position, application method, and tightness of the abdominal band. The data were analyzed by the repeated measure one-way ANOVA, and Wilcoxon signed rank test. The findings were as follows: 1. All phase of the patients' pulmonary function improved significantly in supine posture in contrast to standing (vital capacity by $0.46{\ell}$ and expiratory reserve volume by $0.09{\ell}$). 2. The longer the time lapsed from supine posture to standing, the patient's expiratory reserve volume, maximum ventilation volume, vital capacity, and forced expiratory volume increased. 3. When the patient lay in supine position, the maximum ventilation volume, vital capacity, and the forced vital capacity increased then the center line of the abdominal band was placed along iliac crest; on the other hand, when the patient was standing, placing the bottom line of the abdominal band along iliac crest increased the maximum ventilation volume, vital capacity, and forced expiratory volume. 4. In placing the abdominal band in the patients, leaving space between the top and bottom lines of the band helped increased in maximum ventilation volume, vital capacity, and forced vital capacity for patient in supine as well as in standing. 5. When placing the abdominal band to patients in supine posture, reducing the length of the band by 2.5% along the patient's waist line increased the patients' vital capacity, while reducing the length by 10% to patients in standing increased the maximum ventilation volume. The abdominal band should be placed in such a way that the bottom part of the band should be more tightly fastened while leaving enough room for a hand to be placed in between the body and the band for the top part of the hand. It should also be noted that in a supine position, the bottom line of the band should be placed along the iliac crest, while in standing, the center line should be placed along the iliac crest. The length of the band should also be reduced by 2.5% of the waist line in supine position, and in standing, the length should be reduced by 10%. It should also be noted that the pulmonary function of the patients should be measured at least 10 minutes after one position change.

• 한국전자파학회논문지
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• 제14권5호
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• pp.521-526
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• 2003

본 논문에서는 Ka-band에 대한 반사형 아날로그 위상변화기의 설계 및 제작결과를 기술하였다. 큰 위상 변화를 가지기 위해서 병렬의 GaAs hyperabrupt junction 바랙터 다이오드와 리액턴스 정합 방법을 사용하였으며 이론적인 설계공식도 도출하였다. Ka-band에서는 조립과정도 중요하며 조립과정중 발생할 수 있는 기생성분을 최소화하기 위한 조립절차도 포함하였다. 제작결과는 Ka-Band에서 기존 것보다 큰 220$^{\circ}$$\pm$7$^{\circ}$ 가변의 위상변화와 삽입손실이 5 dB$\pm$1 dB를 가진 우수한 성능의 측정된 결과를 얻었다.

• 한국측량학회지
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• 제33권3호
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• pp.203-209
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• 2015

This paper discusses the effectiveness of using Landsat 8 TIR (Thermal Infrared) band images to improve the accuracy of landuse/landcover classification of urban areas. According to classification results for the study area using diverse band combinations, the classification accuracy using an image fusion process in which the TIR band is added to the visible and near infrared band was improved by 4.0%, compared to that using a band combination that does not consider the TIR band. For urban area landuse/landcover classification in particular, the producer’s accuracy and user’s accuracy values were improved by 10.2% and 3.8%, respectively. When MLC (Maximum Likelihood Classification), which is commonly applied to remote sensing images, was used, the TIR band images helped obtain a higher discriminant analysis in landuse/landcover classification.