• Journal of the Institute of Electronics Engineers of Korea SC
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• v.47 no.5
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• pp.43-51
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• 2010

Attenuation coefficients of medical ultrasound not only reflect the pathological information of tissues scanned but also provide the quantitative information to compensate the decay of backscattered signals for other medical ultrasound parameters. Based on the frequency-selective attenuation property of human tissues, attenuation estimation methods in spectral domain have difficulties for real-time implementation due to the complexicity while estimation methods in time domain do not achieve the compensation for the diffraction effect effectively. In this paper, we propose the modified VSA method, which compensates the diffraction with reference phantom in time domain, using adaptive bandpass filters with decreasing center frequencies along depths. The adaptive bandpass filtering technique minimizes the distortion of relative echogenicity of wideband transmit pulses and maximizes the signal-to-noise ratio due to the random scattering, especially at deeper depths. Since the filtering center frequencies change according to the accumulated attenuation, the proposed algorithm improves estimation accuracy and precision comparing to the fixed filtering method. Computer simulation and experimental results using tissue-mimicking phantoms demonstrate that the distortion of relative echogenicity is decreased at deeper depths, and the accuracy of attenuation estimation is improved by 5.1% and the standard deviation is decreased by 46.9% for the entire scan depth.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.39 no.2
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• pp.35-44
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• 2002

The translation and the rotation of camera occur global motion which affects all over the frame in video sequence. With the video sequences containing global motion, it is practically impossible to extract exact video objects and to calculate genuine object motions. Therefore, high compression ratio cannot be achieved due to the large motion vectors. This problem can be solved when the global motion compensated frames are used. The existing camera motion estimation methods for global motion compensation have a large amount of computations in common. In this paper, we propose a simple global motion estimation algorithm that consists of linear equations without any repetition. The algorithm uses information .of symmetric points in the frame of the video sequence. The discriminant conditions to distinguish regions belonging to distant view from foreground in the frame are presented. Only for the distant view satisfying the discriminant conditions, the linear equations for the panning, tilting, and zooming parameters are applied. From the experimental results using the MPEG test sequences, we can confirm that the proposed algorithm estimates correct global motion parameters. Moreover the real-time capability of the proposed technique can be applicable to many MPEG-4 and MPEG-7 related areas.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.23 no.4
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• pp.141-160
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• 2012

National libraries have an obligation to meet the information needs of users by collecting as many various materials as possible. As legal deposit accounts for the highest percentage of the collection building methods of national libraries, they are trying to encourage the legal deposit of the publishers. However, the rate of legal deposit for the most publishers are pretty low. Therefore, in this study, the improvement plans of legal deposit system for the purpose of helping legal deposit of national libraries improve smoothly has been investigated by identifying the problems with the legal deposit system that publishers had and by suggesting the matters that should be improved based on the recognition of legal deposit by publishers. The plans for the revitalization of legal deposit for the publishers are as follows: promoting factors of legal deposit systems such as scope, deadline, compensation, fine and legal deposit libraries, simplification of legal deposit procedures, set-up of automated online system for legal deposit and strengthening of the method for promoting and educating the legal deposit.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.49 no.7
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• pp.1-9
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• 2012

In this paper, resistance temperature detector (RTD) integrated into the LED package is proposed in order to solve the temperature dependence of LED's optical properties. To measure the package temperature in real time, the RTD type temperature sensor having excellent accuracy and linearity between temperature change and resistance change was adopted. A stable metallic film is required for long term reliability and stability of the RTD type temperature sensor. Therefore, deposition and annealing condition for the film were determined. Based on the determined condition, the RTD type temperature sensor with the sensitivity of about $1.560{\Omega}/^{\circ}C$ was fabricated inside the LED package. In order to configurate the LED package system keeping the constant brightness regardless of the temperature, additional conversion circuit and control circuit boards were fabricated and added to the fabricated LED package. The proposed system was designed to compensate the light intensity caused by temperature change using the variable duty rate of driving current. As a result, the duty rate of PWM signal which is the output signal of the configurated system was changed with the temperature change, and the duty rate was similarly varied with the target duty rate. Consequently, it was focused the fabricated RTD can be used for compensating the optical properties of LED and the LED package which exhibits constant brightness regardless of the temperature change.

• The Journal of the Korea Contents Association
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• v.22 no.1
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• pp.591-600
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• 2022

This study examined the participation of the people with stroke living in the community in terms of productivity, leisure, and social domain, and identified the effect on disability acceptance and anxiety. For data collection, from October 2018 to January 2019, data on disability acceptance, anxiety, and participation were collected from 192 people with stroke who used welfare centers and community services. For general characteristics, t-test and one-way ANOVA were used to compare participation according to descriptive statistics and general characteristics. Pearson correlation analysis was used for correlation between variables, and multiple regression analysis was used to identify causality. As the result, factors affecting the productivity of participation were labor(β=.28, p<.001), de-emphasis on disability salience(β=.14, p<.05), compensatory(β=.22, p<.01), and subjective anxiety(β=-.35, p<.05), and the explanatory power was 33%(F=9.44, p<.001). Leisure was expressed as self-satisfaction with disability(β=.18, p<.05) and the compensatory(β=.18, p<.05), and had an explanatory power of 23%(F=6.32, p<.001). Social activity was labor(β=.19, p<.01), and subjective anxiety(β=-.51, p<.05), which showed 23%(F=6.05, p<.001) of explanatory power. This suggests the importance of psychosocial factors for a changed life after the onset of a stroke, and a practical approach is needed to construct and apply programs to improve participation.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.2 no.1
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• pp.109-131
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• 2007

The purpose of this study were to a) clarify the current practice of internal marketing by contracted food service management companies, b) analyze the effectiveness of current internal marketing practices. The survey was conducted between October 12 and November 2, 2002 with the 10 contracted food service management companies; 6 large, and 4 small & medium sized companies. No significant difference was existed with the categories of internal marketing. However significant differences were existed with the service education, sanitary education, periodic interviews, rewards for best employees, incentive payments, paid -leave allowances, job function allowances, and position classes including unit manager, dietician and cook of MBO. The actual administration of internal marketing strategies showed that, the significant differences were existed with education, paid-leave, and employee welfare systems among position classes. Also the significant differences were existed with all categories of internal marketing between large and small & medium sized companies. In general, small & medium sized companies score of the internal marketing performance was lower than that of large sized companies. Therefore, the segmented internal marketing strategies depending on the analysis not only demand for employees but also the size of company, were required to be an effectively and efficiently managed contracted food management companies.

• The Journal of the Korea Contents Association
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• v.13 no.9
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• pp.270-280
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• 2013

The Purpose of this study was to investigate the relationship between congenital muscular torticollis and maternal work activity. This study was conducted with a total of 89 outpatient pregnant women whose child presented congenital muscular torticollis at the Department of Rehabilitation of "C" Hospital in Suwon within the period from 2006 to April 30, 2011. The results were as followings: (1) The mean age at the time of giving birth was 30.09years; the proportion of pregnant women with college education or higher was high; the proportion of first delivery was 82.0%; the most common way of delivery was natural childbirth, followed by Cesarean section and vacuum extraction; the proportion of breech delivery was 20.2%; and in 82.0% of the women, the first child had congenital muscular torticollis. (2) 59.6% of the women had a career; 45.3% had engaged in professional practice or had a related job; 75.5% had worked until the third trimester of their pregnancy; 54.7% had worked for seven hours or more in a seated position; and the mean number of working hours was 8.75 (3) The level of work-related stress was a low 25% or less, and in the subdivisions of work-related stress, only the level of strained relations belonged to the upper 50% or higher. (4) For the correlation between the survey respondents' job stress and job features, stress (full score: 100 points) showed a strong positive correlation with job demand, strained relations, inadequate reward, and workplace culture. Workplace also showed a strong positive correlation with inadequate reward. Mean daily working hours showed a strong positive correlation with mean weekly working hours.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.4B
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• pp.771-782
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• 2000

In this paper, an H.263 video codec is implemented by adopting the concept of hardware and software co-design. Each module of the codec is investigated to find which approach between hardware and software is better to achieve real-time processing speed as well as flexibility. The hardware portion includes motion-related engines, such as motion estimation and compensation, and a memory control part. The remaining portion of theH.263 video codec is implemented in software using a RISC processor. This paper also introduces efficient design methods for hardware and software modules. In hardware, an area-efficient architecture for the motion estimator of a multi-resolution block matching algorithm using multiple candidates and spatial correlation in motion vector fields (MRMCS), is suggested to reduce the chip size. Software optimization techniques are also explored by using the statistics of transformed coefficients and the minimum sum of absolute difference (SAD)obtained from the motion estimator.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.9 no.1
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• pp.54-62
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• 1995

This paper is a study on a speed control of an induction motor used the MRA-DSM(Mode1 Reference Adaptive-Discrete Sliding Mode) controller. In this paper, when controls motor speed, DSM algorithm is proposed for having Robustness against disturbance and parameter variation. and it is also proposed MRA-DSM including the additional load model reference algorithm, which can be compensated the discontinuous control imputs at sliding mode and followed the model Preference independent of parameter variation of control subjects. The control system is composed of the parallel processing control system using the microprocessor for maximizing the performance of control systems and the real time processing. Also it simplifies the hardware composed of controlling the system by software and improves the reliability of the system. And while MRA-DSM control, faster response characteristics of 27.2 % is obtained than DSM control.

• Journal of KIISE:Software and Applications
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• v.36 no.8
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• pp.616-622
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• 2009

Thanks to Dynamic Capacitance Control (DCC) technique, response time of an LCD display has greatly improved. However, DCC requires hi-speed memory for the real-time writing/reading of an image of a previous frame, which results in increases in hardware overhead and cost. In this paper, we propose Modified Exponential Golomb (MEG) coding, a low-complex high-speed image compression method, which can remarkably reduce memory requirement for DCC. We also propose a pixel-wise DCC switching technique to prevent a compression error from affecting the quality of a final image on LCD. In our experiment, the degradation in visual quality was not noticeable when we cut the DCC memory size of 1080i HD data by 1/3.