• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.11
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• pp.1528-1538
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• 2016

Common data link systems are designed to transmit the imaginary and signal intelligence data at long distance air-ground line of sight(LOS) link. In this paper, we analyze the received power variation according to the communication distance of the common data link using curved earth 2-Ray model suitable for received signal power analysis of long distance air-ground wireless channel. We propose optimal elevation angle control method of the receiving antenna to reduce a power variation caused by ground-reflected wave. Proposed method can get additional link margin compared to the conventional method without any additional hardware performance enhancement.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.37 no.10
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• pp.1-8
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• 2000

In this paper, positioning schemes based on AOA(Angle of Arrival), TOA(Time of Arrival), and TDOA(Time Difference of Arrival) measurements are reviewed and analyzed. In the case of using those schemes in microcell structure with severe multipath fading and shadowing conditions, the rapid and unpredictable variation of signal level makes it difficult to estimate the position and velocity of mobiles. Therefore, we propose a novel mobile tracking method based on the multicriteria decision making, in which uncertain parameters such as RSS(Received Signal Strength), the distance between mobile and base station, the moving direction, and the previous location are participated in the decision process using aggregation function in fuzzy set theory. Through a simulation, we analysis the impaction of the frequent change of direction and speed of mobiles.

• Journal of Biomedical Engineering Research
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• v.38 no.6
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• pp.336-341
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• 2017

The aim of this study is to determine the effect of virtual reality(VR) exercise using XBOX $Kinect^{TM}$ on the scoliometer angle and muscle activities of the trunk. The subjects of the study were 13 young adults who devided into a virtual reality-based exercise group(VREG, n = 7) and a traditional stabilization exercise group(TSEG, n = 6). The VREG received virtual reality game for 5 days a weeks, 30 minutes a day, for a 2 weeks and the TSEG received general trunk stabilization exercise for the same period and frequency. The subjects were measured and compared for muscle activities of trunk stabilization before and after the program. VREG tend to decrease more than TSEG in scoliometer angle. In addition, VREG showed a significant decrease in muscle activities of multifidus. This study presents the impact of virtual reality-based exercise program on trunk balance and stabilization. The following studies need customized programs for subjects that trunk balance and stabilization is required.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.12B
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• pp.1491-1497
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• 2009

Existing methods to measure are based on ToA (Timer of Arrival), RSS (Received Signal Strength), AoA(Angle of Arrival) and other methods. In this paper, we propose a compensation of ToA and RSS methods to measure more precisely the distance of nodes. The comparison experiments with the traditional ToA method show that the average error value of proposed method is reduced 30%. We believe that this proposal can improve location estimation of sensor nodes in wireless sensor networks.

• The Journal of Korean Physical Therapy
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• v.27 no.1
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• pp.24-29
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• 2015

Purpose: The purpose of this study was to investigate the effect of lower limb training using a sliding rehabilitation machine on the foot motion and stability in stroke patients. Methods: Thirty participants were allocated to two groups: Training group (n=15) and Control group (n=15). Subjects in the control group received physical therapy for 30 minutes, five times per week, and those in the training group received lower limb training using a sliding rehabilitation machine for 30 minutes, five times per week, with physical therapy for 30 minutes, five times per week, during a period of six weeks. Heel rotation, hallux stiffness, foot balance, metatarsal load, toe out angle, and subtalar joint flexibility were measured by RS-scan. Results: Significant improvement of the foot motion (hallux stiffness, meta load) and the foot stability (toe out angle, subtalar joint flexibility) was observed in the training group. Conclusion: This study demonstrated that lower limb training using a sliding rehabilitation machine is an effective intervention to improve the foot motion and stability.

• The Journal of Korean Physical Therapy
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• v.26 no.4
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• pp.240-248
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• 2014

Purpose: The purpose of study was to determine the effects of muscle reeducation training in patients with acute facial nerve paralysis. Methods: Thirty patients were randomly assigned to either the experimental group (n=15) or the control group (n=15). The experimental group received muscle reeducation training for 20 minutes after electrotherapy and the control group received conventional electrotherapy for only 40 minutes. Therapeutic intervention for each group was performed four times per week for four weeks. The patients were measured for recovery of paralysis using the House-Brackmann Grading System (H-B grade), the Movement Distance of Mouth, Nasolabial Angle (NA), and Facial Disability Index (FDI). Results: In within group comparison, the experimental group showed significant improvements for all variables (p<0.01). In comparison between two groups, the experimental group showed relatively greater significant improvements for all variables (p<0.01). Conclusion: These findings suggest that muscle reeducation training is more effective than conventional therapy in improving the condition of patients with facial nerve paralysis. In particular, the results of this study indicate that muscle reeducation training can be recommended by clinicians since it provides more benefits.

• Journal of Veterinary Clinics
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• v.20 no.4
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• pp.467-473
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• 2003

The pelvic radiographs of 47 clinically normal Jindoes (26 dogs and 21 bitches) were investigated to evaluate the coxofemoral joints, prospectively. The hip joints were graded according to the Orthopedic Foundation for Animals criteria of excellent, good, fair, borderline, mild canine hip dysplasia (CHD), moderate CHD, severe CHD. Of the 47 Jindoes evaluated, 8 (17%) were graded as dysplastic, 3 (6.4%) were mildly dysplastic, 3 (6.4%) were moderately dysplastic, and 2 (4.3%) were severly dysplastic. Of the 39 Jindoes graded as normal, 16 (34%) were classified as having excellent hip joint phenotype, 15 (31.9%) were classified as having fair, and 8 (17%) were classified as good. Each hip joint was scored based on the British Veterinary Association/The Kennel Club hip scoring system. The normal hip joint (excellent, fair, good) received score less than 5, while dysplastic hip joint (mild, moderate, severe CHD) received score form 5 to 29. Norberg angle (r=0.76) and femoral angle of inclination (r=0.6) were in inverse proportion to grade of the hip joint (P<0.01). The width of medial joint space was in proportion to grade of hip joint (r=0.7, P<0.01).

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.4
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• pp.477-482
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• 2015

In this paper, an android platform with Unity engine was proposed for the effective 3D presentation of IoT sensor's position to IoT(Internet of Things) users. This android platform based home-gateway was designed with the cooperation of 3D unity engine for 3D texture according to MovieTexture simultaneously. As a result, the 3D presentation technology of IoT sensors was described with Unity based 3D modeling. In this proposed smart gateway, the 3D position was presented with the received RSSI(Received Signal Strength Indicator) and angle of IoT sensors. This 3D Unity launcher can be used for the 3D position, monitoring, and the life managing of IoT sensors with the beacon and 3 dimensional cube-style after the 3D conversion of 2D.

• The Journal of Korean Physical Therapy
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• v.15 no.3
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• pp.173-188
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• 2003

The two groups each consisting of 28 people who had an adult hemiplegia due to a brain injury received two different methods of exercises to reduce the angle to which the affected lower limb rotates externally. The comparisons between the two groups were made for the changes of the angle in external rotations measured between pre and post test. The static balance index values taken during pre and post tests were also compared. In addition, the correlations of the angle to which the affected lower limb rotates externally with static balance index values were analyzed. The result were as follows: 1. A statistical analysis indicated that in group one having taken simple R.O.M exercises, the angle to which the affected lower limb rotates externally and the static balance index values were both significantly different between pre and post test (P<.01). 2. A statistical analysis indicated that in group two having taken a pattern movement, both the angle to which the affected lower limb rotates externally and static balance index values were significantly different between pre and post test (P<.01). 3. A significant difference between simple R.O.M exercises group and pattern movement exercises groupwas shown only for the angle to which affected limb rotates externally not for static balance index values (P<.01), 4. Pearson correlation coefficient for the angle to which the affected limb rotates externally with static balance index values was found to be significant only in pattern movement exercises group (P < .05).

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.3
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• pp.15-21
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• 2017

In the active SONAR system, various studies have been carried out to enhance the resolution of a received signal. In order to obtain higher resolution for detecting a bottoming cylindrical object, the design of a planar array for SONAR is investigated in this paper. It is necessary to employ planar structures for SONAR array to obtain narrower beam pattern which gives high resolution. In this study, the transmit frequency of each acoustic transducer, which consists of an array is 13 kHz. For efficient detection of a target of an asymmetric size, the concept of areal angle is applied, which considers resolution according to both azimuth and elevation angles in array design. In the design, the areal angle is first investigated to satisfy the resolution requirements, and then based on the value of areal angles, the azimuth angle and the elevation angle are calculated respectively to design an array.