• Journal of Communications and Networks
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• 제17권4호
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• pp.370-383
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• 2015

Effective link quality estimation is a vital issue for reliable routing in wireless networks. This paper studies the performance of expected transmission count (ETX) under different traffic loads. Although ETX shows good performance under light load, its performance gets significantly worse when the traffic load is high. A broadcast packet storm due to new route discoveries severely affects the link ETX values under high traffic load, which makes it difficult to find a good path. This paper presents the design and implementation of a variation of ETX called high load - ETX (HETX), which reduces the impact of route request broadcast packets to link metric values under high load. We also propose a reliable routing protocol using link quality metrics, which is called link quality distance vector (LQDV). We conducted the evaluation of the performance of three metrics - HETX, ETX and minimum hop-count. The simulation results show that HETX improves the average route throughput by up to 25% over ETX under high traffic load. Minimum hop-count has poor performance compared with both HETX and ETX at all of the different traffic loads. Under light load, HETX and ETX show the same performance.

• The Journal of Korean Society for Radiation Therapy
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• 제8권1호
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• pp.149-159
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• 1996

This descriptive correlational study was undertaken in order to investigate the relationship of family support and personality with quality of life in patients receiving radiotherapy for cervix cancer and to provide basic data to help them improve a better quality of life. The subjects for this study Were 80 out-patients undergoing a radiation therapy at C university hospital in K-city, from April, 1992 to October, 1994. The data were obtained using a convenience sampling technique. The tools used for this study were Ro's quality of life scale, Kang's family support scale and Wallston & others health locus of control scale. The collected data were analyzed by the SAS program using percentage, mean, standard deviation, pearson's correlation coefficients. The result were as follows : 1. The total average score of the quality of life of the subjects was 138.95(minimum score 121-maximum score 164), item mean score(range 1-5) was 2.95. The total average score of the family support of the subjects was 32.55 (minimum score 16-maximum score 47), item mean score(range 1-5) was 2.95 The total average score of the health locus of control of the subjects was 37.00 (minimum score 24-maximum score 49), item mean score (range 1-6) was 3.36. 2 The results of the analysis of the relationship between the quality of life scale and the health locus of control were as follows : the total average score in the quality of life of internal locus of control scale was 136.97, the total average score in the quality of life of external locus of control scale was 144.90. 3. There was a significant positive correlation between the health locus of control and the quality of life(r = 0.2927, p<0.01). The result of the analysis of the relationship between the each factor in the quality of life and health locus of control were as follows : There were significant differences between the health locus of control and emotional state factor(r=0.1514, p<0.01), economic life factor(r=0.2560, p<0.05), self-esteem factor(r=0.2289, p<0.05), physical state and function factor(r=0.1455, p<0.05), relationship with neighbors factor(r=0.0754, p<0.05), relationship with family factor (r=0.3324, p<0.01). 4. There was a significant positive correlation between the family support and the quality of life(r=0.459, p<0.001). The result of the analysis of the relationship between the each factor in the quality of life and family support were as follows : there were significant differences between family support and emotional state factor (r=0.3891, p<0.01), self-esteem factor(r=0.2661, p<0.05), relationship with family factor (r=0.4353, p<0.001).

• The Journal of Korean Medicine
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• 제27권4호
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• pp.150-155
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• 2006

Object : This study investigated the quality inspection of Schizandra chinensis (Turcz.) Bail distributed in Korea. Methods: To evaluate the quality of these herbal medicines, we carried out TLC pattern analysis, purity, loss on drying, ash, acid-insoluble ash, essential oil contents, dilute ethanol-soluble, water-soluble, ether-soluble extracts and HPLC analysis. Results : As a result, TCL pattern analysis of schizandrin and gomisin A showed Rf=0.64 and 0.74, respectively. To measured content of schizandrin and gomisin A, we quantitatively analyzed using HPLC. The average contents of schizandrin and gomisin A were detected to be 0.60 (${\pm}$0.02)% and 0.12 (${\pm}$0.004)%, respectively. Discussion : As a result of this study, we suggest that the minimum content of schizandrin and gomisin A should be 0.5% and 0.1%, respectively. We could suggest that the minimum of essential oil content should be 0.6 ml.

• Journal of the Korea Society of Computer and Information
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• 제16권9호
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• pp.107-114
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• 2011

Because of boost of communications devices furnishing diverse services and rapid expansion of mobile business, good use and management of the existing network system become very important. Also, offering service corresponding with user communication requirement grades which vary widely in each person, is vital for communication service provider. In this paper, SGOSST, a mechanism of efficient network construction with minimum cost for network QoS is proposed. In experiments, though spending 252.97% more execution times, our SGOSST QoS network consumed 5.11% less connecting costs than the network constructed by weighted minimum spanning tree method. Therefore our mechanism can work well for efficient operation and service providing in the network formed with users and communication devices of various service requirement grade as smart/mobile equipment.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제10권11호
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• pp.3218-3226
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• 2009

A number of on-demand routing protocols for sensor networks have been proposed yet. However, the majority of proposed on-demand routing protocols for sensor networks are not suitable for a relatively poor wireless environment and sensor applications requiring reliable data transmission due to using a hop-count metric for their protocols. In this paper, we proposed a minimum LQI(Link Quality Indicator) based on-demand sensor network routing protocol that is suitable for a relatively poor wireless environment and implemented the proposed routing protocol on a TinyOS. We also compared the implemented protocol with typical hop count based routing protocol by carrying out performance experiments on a multi-hop testbed. The results from these experiments showed that the successful transmission rate of the proposed routing protocol is higher than that of typical hop count based routing protocol over a poor wireless link.

• Journal of Labour Economics
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• 제44권1호
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• pp.31-72
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• 2021

This study uses the 12-21st waves of KLIPS to estimate the effect of the increase in the minimum wage on the individual's labor market transition through a multinomial logit. In particular, we examine whether there was an additional effect of the rapid increase in the minimum wage in 2018. The main results of this study are as follows. First, the increase in the minimum wage in Korea is found to have increased the probability of becoming unemployed for both wage workers and self-employed, but there is no additional impact found from the 2018 minimum wage increase. Second, the increase in the minimum wage is found to increase the likelihood of the self-employed entering into wage workers, especially temporary and daily workers. Third, we have found that the increase in the minimum wage in 2018 adversely affected self-employed people with high school education, and significantly lowered young wage workers entering into self-employed. Our results suggest that the recent increase in the minimum wage may be responsible for declining self-employment rate in Korea, and may have a negative effect on the quality of employment because the increase in minimum wage can lead to an increase in temporary and daily wage workers.

• International Journal of Quality Innovation
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• 제2권1호
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• pp.1-9
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• 2001

As all the other managerial activities, total quality management (TQM) has also inputs into and outputs from the process. Therefore, the principal managerial efficiency criteria of maximum outputs with minimum inputs should be applied to TQM. In this paper, the methodology for the performance evaluation of TQM by Data Envelopment Analysis (DEA) was proposed. DEA is used to measure the efficiency of TQM for each firm with the input and output data obtained by questionnaire. It is found that there are not significant differences between the firms with and without IS09000 certification and between the large and small-sized firms with respect to the TQM efficiency.

• The Journal of Korean Institute of Communications and Information Sciences
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• 제34권4B호
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• pp.349-359
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• 2009

In this paper, we propose a stereo-video transmission method for reduction of delay and maximization of 3D effect. Conventional multimedia synchronization algorithms were designed to achieve minimum delay and synchronize multiple video and audio streams, however, they could not be effective for 3D video transmission. In this paper, we proposed a synchronization algorithm by considering the minimum error of time difference between streams for 3D effect. The minimum error of time difference for 3D effect was derived based on a 3D subjective quality test. We compute display time of the delivered videos within the allowed time-difference and the video are displayed according to the display time. To evaluate the performance of the proposed algorithm, we implemented a real-time video communication system and subjective quality test has been conducted with the proposed system. We found that video quality displayed by the proposed system. We found that video quality displayed by the proposed algorithm ranks 'good' and 'excellent' in the DMOS (Differential Mean Opinion Score) scale, based on the MOS (Mean Opinion Score) test.

• Journal of Oriental Neuropsychiatry
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• 제33권2호
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• pp.143-156
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• 2022

Objectives: The purpose of this study was to evaluate the quality of reporting for case reports published in Journal of Oriental Neuropsychiatry from year 2018 to 2021 compared with year 2013 to 2017 in order to recommend ways to improve the quality of case reports published in the future. Methods: To evaluate the quality of case reports identified by electronic searching in Oriental medicine Advanced Searching Integrated System (OASIS) and by hand searching from archives on peer review system of Journal of Oriental Neuropsychiatry using CAse REport (CARE) guideline. The researcher assessed the quality of reporting based on the CARE guideline as 'Sufficient', 'Not-Sufficient', 'Not-Applicable', and 'Not-Reported' for case reports published from 2018 to 2021 in Journal of Oriental Neuropsychiatry. In addition, it was compared with previous case reports published from 2013 to 2017. Results: Finally, 17 case reports were included for the assessment. General quality of reporting for case reports published from year 2018 to 2021 was improved compared with that of previous case reports published in 2018. The maximum value (46.4%→60.7%, 14.3% increase), the minimum value (22.2%→32.1%, 9.9% increase), and the median value (39.3%→50.0%, 10.7% increase) of the report rate evaluated as 'Sufficient' were generally improved. The maximum value (53.6%→50.0%, 3.6% decrease), minimum value (25.9%→21.4%, 4.5% decrease), and median value (35.7%→32.1%, 3.6% decrease) of the report rate evaluated as 'Not-Sufficient', the maximum value of the report rate evaluated as 'Not-reported' (40.7%→25.9%, 14.8% decrease), the minimum value (14.7%→10.7% decrease), and the intermediate value (14.7% decrease) were also generally improved. Four items (8b, 8d, 10c, and 13) were evaluated as 'Not-Reported'. These items seem to be items that need urgent improvement along with 8c, which showed a significant decrease in reporting rate. Conclusions: There are needs to improve the quality of case reports in Journal of Oriental Neuropsychiatry by comparing case reports published from year 2013 to 2017 with case reports published from year 2018 to 2021. To improve the quality of case reporting, sufficient education at the academic level should be provided on thesis preparation methods. It is also necessary to develop a tool for evaluating the quality of case reporting that reflects characteristics of Korean Medicine.

• Water for future
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• 제27권1호
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• pp.53-67
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• 1994

Water quality analysis in the midstream of the Nakdong river is studied. Deterministic model RQ1 which contains two code, RQ1-1 for hydrologic and hydraulic analysis and RQ1-2 for water quality analysis are developed. Monthly mean and minimum discharges in the basin (from Waegwan to Jindong) are estimated. A varied flow analysis is performed based on the geometric data of channel and RQ-1 model. The maximum concentration of BOD and minimum concentration of DO are occurred at the confluence of Keumho river and immediately downstream of Hyunpoong, respectively. The computed concentrations of BOD at several points have good agreements with observed data. Maximum allowable BOD loads from the Keumho River are provided to attain the goal of water quality in the basin.