• Proceeding of KASS Symposium
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• 2008.05a
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• pp.66-69
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• 2008

This study presents deflection analysis of long span structures for pedestrian bridge on crossroads. For long span structures, the size of structural members should be determined considering the esthetic view and vehicle below the structures. As a result, the slenderness ratio of members is increased and the structure may be suffered from significant deflection. The under-tensioned system on lower part of the structure, is applied in order to reduce the deflection and the size of members. In this regard, the under-tensioned system enables the load of upper parts to carη to the end of beam by means of tensional force in cable. In addition, effectiveness of under-tensioned system can be different depending on the size of cable, the number and spacing of posts. This study is performed with conforming the effect by analytical various parameters (size of cable, number and spacing of post). Dead and live loads is supposed to apply in the slab, and the analytical result by MIDAS program are presented addressing the effect of the under-tensioned system.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.11B
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• pp.1612-1619
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• 2001

This paper examines the design, implementation characteristics of a folded dipole active integrated antenna. Our goal was to minimize the physical size of RF circuit and its insertion loss, and to make the high frequency tuning easier by directly integrating the ISM(Industrial Scientific & Medical) band power amplifier and antenna. Non-linear model has been used for highly accurate simulation of the power amplifier. The maximum power level was found by using the Load pull method before an impedance matching was achieved. It is found that the total power-added efficiency(PAE) including the driving amplifier was 31.5% and that the transmit power was 13.7 dBm. We also found that the proposed scheme with the smaller antenna as compared with the existing dipole antenna has 23.7 dB total gain including the antenna gain. The suppression of the second harmonic signal to the fundamental signal with respect to the fundamental signal was found to be more than 30 dBc.

• Journal of the Korea Concrete Institute
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• v.18 no.6 s.96
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• pp.729-736
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• 2006

It has been shown that many Reinforced Concrete(RC) structures designed without seismic details have experienced brittle shear failures in the beam-column joint area and resulted in large permanent deformations and structural collapse. In this study, experimental investigations into the performance of exterior reinforced concrete beam-column joints strengthened with the carbon fiber-reinforced polymer(CFRP) under cyclic loading were presented. The CFRP has been applied by choosing different combinations and locations to determine the effective way to improve structural performances of joints. Eight beam-column joints were tested to investigate behaviors of each specimen under cyclic load and to compare performances of seismic retrofit. According to the experimental study, the retrofit strengthened with the CFRP provides significant improvements of flexural capacity and ductility of beam-column joints originally built without seismic details.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.6
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• pp.9-17
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• 2014

Heterogeneous network (HetNet) is a network consisting of macrocells overlaid with small cells. In HetNet, the interference from macrocell to small cell users is a major cause of performance degradation of small cell users and enhanced inter-cell interference coordination (eICIC) is needed to mitigate the interference. Previous works on eICIC gives limited performance gain because these works focus on maximizing long-term throughput and rarely consider varying channel conditions over frames. This paper proposes a new algorithm which dynamically coordinates interference and schedules users on each frame to maximize the total utility of the network with lower computational complexity than exhaustive search. Simulation results show that the proposed algorithm achieves higher total throughput than the throughput with the conventional algorithm, and has higher fairness index than the conventional algorithm when there large number of users.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.8 s.350
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• pp.59-68
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• 2006

The study on the uniform error property of codes has been restricted to additive white Gaussian noise (AWGN) channel, which is generally referred to as geometrical uniformity. In this paper, we extend the uniform error property to space-time codes in multiple-input multiple-output (MIMO) channel by directly treating the probability density functions fully describing the transmission channel and the receiver. Moreover, we provide the code construction procedure for the geometrically uniform space-time trellis codes in fast MIMO channels, which consider the distance spectrum. Due to the uniform error property, the complexity of code search is extensively reduced. Such reduction makes it possible to obtain the optimal space-time trellis codes with high order states. Simulation results show that new codes offer a better performance in fast MIMO channels than other known codes.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.3
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• pp.3-9
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• 2014

Two-way full-duplex relay network provides improved spectral efficiency by using either superposition coding or physical layer network coding at relays compared to conventional two-way half-duplex relay network. In this paper, we investigate the impact of residual loop interference on the performance of the two-way full-duplex relay network. Users and relays in the two-way full-duplex relay network estimate the residual loop interference in order to cancel it. However, it is difficult to perfectly cancel the residual loop interference from the received signal due to the estimation error. Numerical results show the impact of the estimation error on the outage probability of the two-way full-duplex relay network.

• Journal of Broadcast Engineering
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• v.14 no.6
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• pp.721-732
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• 2009

AT-DMB system has been developed to increase data rate up to double of conventional T-DMB in same bandwidth while maintaining backward compatibility. The AT-DMB system adopted hierarchical modulation which adds BPSK signal or QPSK signal as enhanced layer to existing DQPSK signal. The enhanced layer signal should be small enough to maintain backward compatibility and to minimize the coverage loss of existing T-DMB service area. But this causes the enhanced layer signal of AT-DMB susceptible to fading effect in transmission channel. A turbo code which has powerful error correction capability is applied to the enhanced layer signal of the AT-DMB system for compensating channel distortion. We developed the prototype AT-DMB transmitter and receiver systems for performance evaluation. LAB test for analysing the effect of constellation ratio between existing base layer signal and enhancement layer signal, was conducted and the measurement results are shown with analysis comments.

• The Journal of Internal Korean Medicine
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• v.37 no.6
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• pp.940-948
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• 2016

Objectives: This exploratory trial evaluated the possibility of quantitatively measuring several aspects during the "abdominal examination" of traditional Korean medicine. The main results of this study will be used to develop a new diagnostic device for abdominal examinations. Methods: Fifteen healthy volunteers were recruited for this study. Three certified Korean medical doctors assessed the existence of pressure pain, the elasticity of the abdominal muscle, and the tonus at CV12 as gold standards. Then, 2 well-trained investigators measured the pressure pain threshold (PPT), the indentation depth of a bar, and repelling force by pressing CV12. Each investigator measured the above 3 variables 2 times at 1 min intervals using a modified digital algometer. Reliability and validity tests of the 3 variables were performed. Results: There were statistically significant coefficients of intraclass correlation on the 3 variables both between and within the investigators (P<0.001). Also, PPT and repelling force showed statistically significant high sensitivity and specificity in a ROC curve. However, the indentation depth of the bar presented relatively low sensitivity. Conclusions: This new diagnostic method using a modified digital algometer could be a useful tool for quantitative measurement in "abdominal examinations". However, future rigorous clinical studies with a large population will be needed for the verification of its usefulness.

• Journal of Mushroom
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• v.13 no.4
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• pp.310-313
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• 2015

This study was carried out to re-use the post-harvest substrate of Pleurotus pulmonarius. In this study, we used two mixing ratio. First, a mixing ratio is developed by Gangwon Province Agriculturl Research and Extension Services[Poplar sawdust(10)+Cottonseed hull(50)+Cottonseed mal(20)+Beet pulp(20)]. Second, mixing ratio is developed by farmers[Poplar sawdust(60)+Cottonseed hull(10)+Cottonseed mal(10)+Beet pulp(20)]. First mixing ratio research results, Hosan was no difference in the yield by 30%, Yield of the Hwasan has increased by 20%. Second mixing ratio research results, Hosan was no difference in the yield by 20%. However, Hwasan has decreased.

• Journal of The Korean Society of Integrative Medicine
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• v.8 no.1
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• pp.1-14
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• 2020

Purpose : The purpose of this study was to investigate the effect of an exercise program with patella mobilization on range of motion, muscle strength, and gait in patients with total knee arthroplasty. Methods : Thirty patients under the age of 65 who visited the T hospital in Daegu Metropolitan City and underwent total knee arthroplasty surgery were selected for this study. Fifteen patients were randomly assigned to the experimental group and took part in an exercise program with patella mobilization, and fifteen patients were randomly assigned to the control group and took part in just the exercise program. Each group took part in their intervention three times a week for four weeks. The measurement tools used included a goniometer, handheld dynamometer, and 10-meter walking test. In the statistical analysis results, to compare the about pre and post test differences within each group, a paried t-test was used, and to compare the differences between each group, an independent t-test was used. Results : There was a significant difference (p<.05) in the range of motion, muscle strength of the quadriceps femoris and, hamstrings, and 10-meter walking test within each individual group and between the two groups before and after the intervention (p<.05). Conclusion : All the results for the experimental group were significant. Therefore, it is expected that an exercise program with patella mobilization will be helpful for the recovery of the knee joint in patients who have undergone total knee arthroplasty.