• Physical Therapy Korea
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• v.16 no.4
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• pp.37-43
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• 2009

This study compared the electromyographic activities and input performance of computer operators using a computer mouse and a trackball. Muscle activities were assessed at the upper trapezius (UT), middle deltoid (MD), extensor digitorum (ED), and first dorsal interosseous muscle (FDI). Twenty-six healthy subjects were recruited, and the test order was selected randomly for each subject. The task set was to click moving targets on a Windows program. The EMG amplitude was normalized using the percentage of reference voluntary contraction for UT and MD and the percentage of maximal voluntary contraction for ED and FDI. To analyze the differences in EMG activity, a paired t-test was used. UT muscle activities were significantly greater when the computer mouse was used (p<.05). FDI muscle activities were significantly greater when the trackball was used (p<.05). Using a trackball can reduce the load on the UT during computer work and help to prevent and manage work-related musculoskeletal disorders.

• Korean Journal of Remote Sensing
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• v.30 no.3
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• pp.375-381
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• 2014

Soil moisture is an essential satellite-driven variable for understanding hydrologic, pedologic and geomorphic processes. The European Space Agency (ESA) has endorsed soil moisture as one of Climate Change Initiates (CCI) and had merged multi-satellites over 30 years. The $0.25^{\circ}$ coarse resolution soil moisture satellite data showed correlations with variables of a water stress index, Temperature-Vegetation Dryness Index (TVDI), from a stepwise regression analysis. The ancillary data from TVDI, Land Surface Temperature (LST) and Normalized Difference Vegetation Index (NDVI) from MODIS were inputted to a multi-regression analysis for estimating the surface soil moisture. The estimated soil moisture was validated with in-situ soil moisture data from April, 2012 to March, 2013 at Andong observation sites in South Korea. The soil moisture estimated using satellite-based LST and NDVI showed a good agreement with the observed ground data that this approach is plausible to define spatial distribution of surface soil moisture.

• Journal of Power Electronics
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• v.12 no.1
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• pp.120-127
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• 2012

Fault diagnosis technique of electrical drives is becoming more and more important, since voltage fed converter system has become industrial standard in many applications. Many studies have been conducted an inverter fault diagnosis for induction motors. However, there are few researches about fault diagnosis of 3-phase ac/dc PWM (Pulse Width Modulation) converter compared to the dc/ ac inverter. The ac/dc converter is the opposite of dc/ac inverter at current flow. Also, inverter and converter have different current patterns under the same condition of IGBT (Insulated gate bipolar transistor) open switch fault. Therefore, it is difficult to apply intact diagnosis methods of inverter to the converter. This paper proposes modified fault detection methods for IGBT open switch fault in 3-phase ac/dc PWM converter by modifying established fault diagnostic methods for dc/ac inverters.

• Journal of International Academy of Physical Therapy Research
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• v.1 no.1
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• pp.45-51
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• 2010

2 week study was conducted to investigate the effects of Interferential Current(IC) and Kaltenborn-Evjenth Orthopedic Manual Therapy(KEOMT) on functional constipation. Interventions were applied to spinal segments between $T_9-L_2$ which provides innervations to the gastrointestinal tract. Subjects(n=24) were randomly allocated to two treatment groups: the IC group or the KEOMT group. Results for the IC therapy demonstrated significant decrease with the colonic transit time(CTT) as well as scores on the constipation assessment scale(CAS). The frequency of defecations per week had increased significantly(p<0.05). The KEOMT displayed decreased CTT in the left colon region. The scores on the CAS were reduced and frequency of defecations per week had increased significantly (p<0.05). This study not only showed that both modes of therapy improved symptoms of constipation, but also optimized gastrointesti. nal content movement, eventuating in a more normalized CTT. In conclusion, both the IC therapy and the Kaltenborn-Evjenth Orthopedic Manual Therapy have shown to be effective interventions for improving functional constipation.

• Korean Journal of Head & Neck Oncology
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• v.23 no.1
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• pp.41-45
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• 2007

A 60 years old female patient presented with $8{\times}6\;cm$ sized painless oval mass in the left parietal region. She had left lobectomy of thyroid gland 10 years ago. Cranial CT, MRI, FGD PET-CT showed a solid mass which invaded left parietal bone. After embolization, craniectomy with tumor excision was performed. Histological examination revealed metastatic follicular cancer originated thyroid gland, with vascular and dura invasion. Postoperatively, neck CT showed right thyroid multiple nodules and right level III multiple lymph node enlargement. Thyroid function test was normal, but level of thyroglobulin was high (72ng/ml). So she had right lobectomy of thyroid gland with lymph node dissection under a diagnosis of follicular carcinoma. But histological examination revealed adenomatous hyperplasia and not lymph node metastasis. After operation, she received radioiodine therapy of 150mCi and then the level of thyroglobulin normalized (8.4ng/ml). The patient is under follow-up since she had operation 4 months ago.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2008.11a
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• pp.193-196
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• 2008

지상파 DMB 동일 채널 중계기에서는 송신 안테나로부터 수신 안테나로 재입력되는 궤환 신호가 존재한다. 이 궤환 신호는 적절히 제거되지 않을 경우 수신 신호에 간섭으로 작용하게 되어 중계기 시스템의 안정성이 크게 떨어지게 된다. 과거에 진행된 연구에서는 궤환 채널을 추정하여 간섭을 제거시키는 궤환 신호 제거기(feedback canceller) 를 사용하여 이와 같은 문제를 해결하였다. 하지만 기존의 추정 알고리즘은 간단한 구현에 비해 수렴 성능과 속도 면에서 만족할만한 성능을 얻을 수 없었으며, 신호 간 상관도 제거를 위해 충분한 시간 지연을 해야 하는 단점이 있다. 본 논문은 궤환 채널 추정에 적합한 PNLMS (Proportionate Normalized Least Mean Squares) 적응형 알고리즘을 적용해 새로운 궤환 신호 제거 기법을 제안하였으며, 전산 모의 실험을 통해 이와 같은 문제를 효과적으로 해결할 수 있음을 보여준다.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.17 no.1
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• pp.279-286
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• 1987

The authors observed a patient who referred to the Department of Oral Radiology, due to diffuse skeletal pain, muscular weakness and unknown tumor mass on the buccal gingiva of upper right molar region. The patient was found to have peripheral reparative giant cell granuloma and osteomalacia. After removal of the tumor, the clinical, radiologic, and laboratory findings of the patient was rapidly normalized with remarkable improvement of bone pain. The results were as follows: 1. After removal of the tumor, the patient improved. the clinical findings such as bone pain, trismus. muscular weakness and he could walk. 2. In postoperative x-ray findings at 1 and 2 months intervals, the lamina dura of all dentition and bony trabeculae in upper and lower arches were regenerating and the bone density increased. 3. In periodic recall check, no occurrence of osteomalacia was existed and the laboratory findings of the patient showed gradual improvement.

• Journal of the Korean Society for Heat Treatment
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• v.27 no.2
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• pp.72-78
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• 2014

Isothermal transformation behavior of a 10% Cr heat resistant steel fabricated by centrifugal casting process was investigated. Normalized specimen at $1100^{\circ}C$ for 1 hour was isothermally annealed at temperature range between $600^{\circ}C$ and $700^{\circ}C$ with various time. The annealed specimen had eutectoid structure which was generated along austenitic grain boundary during isothermal annealing. Areal fraction of eutectoid structure increased up to 25% after holding at $700^{\circ}C$ for 20 hours. It was observed that austenitic matrix was transformed to ferrite structure and fine $M_{23}C_6$ carbides with increase of annealing time. Time-temperature-transformation diagram of the centrifugally cast 10% Cr steel with 0.18 wt% C was plotted based on the results of isothermal transformation behavior.

• Korean Journal of Remote Sensing
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• v.28 no.3
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• pp.277-285
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• 2012

The GOCI imagery can be an effective alternative to monitor short-term changes over terrestrial environments. This study aimed to assess the radiometric characteristics of the GOCI multispectral imagery for land applications. As an initial approach, we compared GOCI at-sensor radiance with MODIS data obtained simultaneously. Dynamic range of GOCI radiance was larger than MODIS over land area. Further, the at-sensor radiance over various land surface targets were tested by vicarious calibration. Surface reflectance were directly measured in field using a portable spectrometer and indirectly derived from the atmospherically corrected MODIS product over relatively homogeneous sites of desert, tidal flat, bare soil, and fallow crop fields. The GOCI radiance values were then simulated by radiative transfer model (6S). In overall, simulated radiance were very similar to the actual radiance extracted from GOCI data. Normalized difference vegetation index (NDVI) calculated from the GOCI bands 5 and 8 shows very close relationship with MODIS NDVI. In this study, the GOCI imagery has shown appropriate radiometric quality to be used for various land applications. Further works are needed to derive surface reflectance over land area after atmospheric correction.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.3
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• pp.162-178
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• 2017

Remote sensing can be used to provide information about the monitoring of crop growth condition. Recently Unmanned Aerial Vehicle (UAV) technology offers new opportunities for assessing crop growth condition using UAV imagery. The objective of this study was to assess weather UAV aerial images are suitable for the monitoring of highland Kimchi cabbage. This study was conducted using a fixed-wing UAV (Model : Ebee) with Cannon S110, IXUS/ELPH camera during farming season from 2015 to 2016 in the main production area of highland Kimchi cabbage, Anbandegi, Maebongsan, and Gwinemi. The Normalized Difference Vegetation Index (NDVI) by using UAV images was stable and suitable for monitoring of Kimchi cabbage situation. There were strong relationships between UAV NDVI and the growth parameters (the plant height and leaf width) ($R^2{\geq}0.94$). The tendency of UAV NDVI according to Kimchi cabbage growth was similar in the same area for two years (2015~2016). It means that if UAV image may be collected several years, UAV images could be used for estimation of the stage of growth and situation of Kimchi cabbage cultivation.