• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.8
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• pp.1376-1385
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• 2000

The phase characteristic of delay line in feedfarward linearizer has been changed due to variation of operating temperature. In this paper, design method of fixed phase control circuit of group delay line using adaptive vector control is derived. To maintain transfer characteristics of nominal operating temperature, the error correlated signals, which are changed adaptively due to changing of temperature, are added to main signals. The proposed method maintains transfer characteristics under 0.06dB of insertion loss and 0.36$^{\circ}$ of phase variation in case of 1-tone(880 MHz) and under 0.07 dB of insertion loss and 0.35$^{\circ}$ of phase variation in case of 2-tones(877 MHz, 882 MHz) for 10dB input power dynamic range and +/-10$^{\circ}$ phase variation respectively.

• Journal of Multimedia Information System
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• v.3 no.4
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• pp.141-148
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• 2016

This paper proposes a medium access control (MAC) protocol for multiple-input multiple-output (MIMO) ad-hoc networks. Multiple-packet receptions in MIMO systems have attracted as a key technique to achieve a high transmission rate. In the conventional protocols for multiple-packet receptions, timing offsets among multiple-frame transmissions cause frame collisions induced by hidden nodes, which degrades network performance. In the proposed protocol, transmission synchronization among hidden nodes can be achieved by applying pulse/tone exchanges. By applying the pulse/tone exchanges, multiple-packet receptions among hidden nodes can be achieved, which enhances network throughputs compared with the conventional protocol. Simulation results show effectiveness of the proposed protocol.

• ETRI Journal
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• v.34 no.1
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• pp.98-101
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• 2012

The directional medium access control (MAC) protocol improves the throughput of mobile ad hoc networks but has a deafness problem and requires location information for neighboring nodes. In the dual-channel directional MAC protocol [12], the use of omnidirectional packets does not require the exact location of destination node. In this letter, we propose a tone dual-channel MAC protocol with directional antennas to improve the throughput of mobile ad hoc networks. In the proposed MAC protocol, we use a directional CTS and an out-of-band directional DATA tone with a new blocking algorithm to improve the spatial reuse. We confirm the throughput performance of the proposed MAC protocol by computer simulations using the Qualnet simulator.

• The Journal of the Acoustical Society of Korea
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• v.24 no.1
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• pp.43-51
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• 2005

In this paper, we propose an algorithm that improves a tone quality of a noisy audio signal in order to enhance a Performance of perceptual filter using noise energy control. Most of the algorithms which were proposed by the other researchers usually applied a filter using the noise energy acquired from a silent range. In this case. the improvement rate of tone quality decreases if the noise energy is changed by the magnitude or environment variation in a signal frame. But the Proposed method Provides the means to find a food estimated noise through energy control of the estimated noise which is obtained from a silent range. Also we can get the enhancement of tone qualify in low frequency band unlike other methods. To show the performance of the Proposed algorithm, various input signals which had a different signal-to-noise ratio (SNR) such as 5dB, l0dB, 15dB and 20dB were used to test the proposed algorithm. With the proposed algorithm, we could confirm the enhancement of tone quality in terms of segmental SNR (SSNR). noise-to-mask ration (NMR) and mean opinion score (MOS) test.

• Physical Therapy Korea
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• v.14 no.1
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• pp.64-73
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• 2007

The purpose of this study was to find any correlations among Postural Assessment Scale for Stroke (PASS), Modified Barthel Index (MBI), Tone Assessment Scale (TAS), Motor Assessment Scale-Gait (MAS-G), Fugl Meyer-Balance (FM-B), and to predict MBI from subscales of the PASS. The subjects were 41 stroke patients of the Korea National Rehabilitation Center in Seoul. The main outcome measures were postural control (PASS), gait (MAS-G), Balance (FM-B), Tone (TAS), ADL (MBI). The data was analyzed using the Pearson product correlation. PASS scale was used between other clinical and instrumental indexes, multiple stepwise regression analyses were performed to identify prognostic factors for ADL incline, and Cronbach's alpha coefficient was used to identify internal consistency on PASS scale. The results of this study areas follows: 1. The highest level was sitting without support, the lowest level was standing on paretic leg on PASS scale. The highest level was chair/bed transfer, the lowest level was bathing on MBI. 2. All items of the PASS, except postural tone were significantly correlated with Gait, Balance, MBI (p<.01), 3. The Internal Consistency (Cronbach's alpha coefficient=.85) was very high, indicating that the PASS is homogeneous and is likely to produce consistent response. Furthermore, the sums of maintaining position items and of changing-position items were strongly correlated (r=.64, p<.05) and there were significant correlations between sums of PASS, sums of maintaining position items (r=.87, p<.01), and changing-position items (r=.93, p<.01). 4. The standing without support of the PASS items was the strongest variance ($R^2$=.85) of the predicting ADL function. These findings provide strong evidence of the predictive value of the postural control on gait, Balance, ADL function in stroke patients and to can provide a reference for the successful therapeutic program and more improved functional recovery.

• Journal of the Korean Society of Physical Medicine
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• v.12 no.3
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• pp.43-47
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• 2017

PURPOSE: The purpose of this study was to identify the effects of physical therapy plus Kinesio taping (KT) on muscle tone and stiffness in patients with shoulder pain. METHODS: This study included 22 participants who were divided into the experimental group (n=11) who underwent a routine physical therapy with KT and the control group (n=11) who received the same physical therapy only. The physical therapy consisted of heat application and electrical stimulation. Heat was applied for 10 minutes and electrical stimulation was conducted for 20 minutes. Intervention was provided over a 1-week period, and frequency for muscle tone and stiffness was measured to determine changes in shoulder muscle status. The muscles were supraspinatus and deltoid. Measurements were taken before, after 1day, 3day and after 1 week to identify time-dependent effects of intervention. RESULTS: The effects of the intervention were significant in both groups, and effects were greater in the experimental group. Changes in muscle tone and stiffness were statistically significant in both groups and at varying time points (p<.05). CONCLUSION: Based on the improved muscle performance found in this study, KT is considered an effective intervention strategy for patients with shoulder pain when it is combined with conventional physical therapy.

• The Korea Journal of Herbology
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• v.38 no.2
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• pp.9-16
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• 2023

Objectives : Many people use natural soap instead of commercially available bar type general soap for skin care. They tend to prefer cp (cold process) type soaps that go through a sufficient maturation process in formulation. The purpose of this study was to investigate the efficacy of PCPS (placenta cp soap). Methods : The researcher selected 36 subjects, 28 as the experimental group and 8 as the control group. I asked participants to wash their face twice a day in the morning and evening, and the period was set for 6 weeks. The researcher had the people who were selected as the control group use a commercially available foam cleanser, meanwhile the experimental group use PCPS. They performed a skin test before the start of the test, and the change status was continuously investigated after 2 weeks, 4 weeks, and 6 weeks after using the soap. Results : In the case of U zone oil and pores, there was a significant decrease and in the case of skin tone, there was a significant increase in the group of using PCPS. In T zone oil change, there was no significant effect in both the experimental group and the control group. Conclusion : In the case of PCPS, it is recommended to use it in the effect of reducing the size of pores and increasing skin tone, but it can reduce u-zone oil content.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.2C
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• pp.217-225
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• 2009

Tone injection scheme has been known as one of peak to average power ratio (PAPR) reduction methods deployable to multi-carrier system like orthogonal frequency division multiplexing (OFDM). The basic idea in tone injection scheme is to enforce the constellation size larger so that each of original constellation points is mapped into the preassigned distinct locations. According to the tone injection scheme, it increases symbol power highly induced inherently by expanding constellation to get optimal PAPR reduction. In the other hand, to get optimal power increase, the PAPR would be reduced insufficiently with limited tone injection signal. To withstand these problems, this paper consider the reduction of the PAPR and power increase problem simultaneously, Toward this, the tone injection scheme accomplished by employing the weighted sum genetic algorithm which has been utilized to solve multi-objective optimization problem (MOOP). The simulation results verifies that the proposed scheme can control the effective PAPR performance and alleviation of power increase flexibly by the weight value at the expense of relatively low complexity.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.17-19
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• 1988

The musical tone of clarinet was synthesized by using nonlinear distortion method. In this method, the control of dynamic spectrum and harmonic contents can be easily attained. The method can be also applied to synthesis of musical tones of many other tonal instruments.

• Proceedings of the KIEE Conference
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• 1987.07b
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• pp.1026-1030
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• 1987

This paper proposes analytic models of the large scale ESS's control system which has the multiprocessor architecture. The performance indices such as the ringback tone delay, busy tone delay, queue length and processor idletime are investigated through the analytic model. The system bottleneck is also analyzed. For the validation of analytic models, its simulation is performed using the SDL/SIM package for the case of 100,000 subscribers. From computer simulation, the results of analytic models are shown to be similar to the results of simulation models, which validates the analytic models.