• Analytical Science and Technology
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• v.6 no.1
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• pp.121-129
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• 1993

UV/VIS spectrophotometer interfaced with HPIC(High Performance Ion Chromatography) has been applied to the determination of lanthanide elements. The separation of lanthanide elements with HPIC helped to avoid erroneous analytical results due to interferences. Individual lanthanide elements at ppm level were separated on a HPIC CS5 column using pyromellitic acid and oxalic acid. The individual lanthanide elements were detected at 520nm following post-column reaction with PAR. Sm, Eu, Gd, Y, Tb, Dy, Ho, Er, Tm, Tb, and Lu were separated by pyromellitic acid. La, Ce, Pr and Nd were separated by oxalic acid. Appropriate pH of pyromellitic acid for separation was at pH 2.99.

• Human Ecology Research
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• v.53 no.1
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• pp.93-106
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• 2015

The purpose of this study is to understand what we have learnt thus far on the sustainable consumption of natural resources by household in Korea. We propose a two-wing model designating households as the main agent of sustainable living where both the production of human resources and the consumption of natural resources take place. In the current study, we focused on the sustainability of natural resource consumption. Undertaking an empirical study, we selected 10 major journals that represent each area of human ecological research and then, identified 120 relevant studies regarding sustainability published since 2000. First, we classified 381 keywords into three categories: production, consumption, and social environment, and the identified studies were then classified in one of the seven categories created by combinations of the abovementioned three categories: production (P), consumption (C), social environment (S), production-consumption (PC), production-social environment (PS), consumption-social environment (CS), and production-consumption-social environment (PCS). The results showed that the sustainability of natural resources has been mainly investigated in the fields of clothing & textiles and food & nutrition. Further, consumer science research has been conducted in the area of consumption-social environment and consumption-production. The current study indicates that the field of human ecology has created and accumulated knowledge to support sustainable living. In the future, we need to conduct more integrated research across disciplines and methods and promote research interest in the underdeveloped area of sustainability research in human ecology.

• Journal of Radiation Protection and Research
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• v.34 no.3
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• pp.102-106
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• 2009

We exposed ICR mice to low-dose (0.2 Gy) and low-dose-rate (0.7 mGy/h) $\gamma$-radiation ($^{137}Cs$) in the Low-dose-rate Irradiation Facility at the Radiation Health Research Institute to evaluate systemic effects of low-dose radiation. We compared the body and organ weights, number of blood cells (white and red blood cells and platelets), levels of biochemical markers in serum, and frequency of micronuclei in polychromatic erythrocytes between low-dose irradiated and non-irradiated control mice. The ICR mice irradiated with total doses of 0.2 and 2 Gy showed no changes in body and organ weights, number of blood cells (white and red blood cells), or frequency of micronuclei in the polychromatic erythrocytes of peripheral blood. However, the number of platelets (P = 0.002) and the liver weight (P < 0.01) were significantly increased in mice exposed to 0.2 and 2 Gy, respectively. These results suggest that a low-dose-rate of 0.7 mGy/h does not induce systemic damage. This dose promotes hematopoiesis in the bone marrow microenvironment and the proliferation of liver cells. In the future, the molecular biological effects of lower doses and dose rates need to be evaluated.

• Journal of Convergence for Information Technology
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• v.10 no.4
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• pp.160-167
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• 2020

This study analyzes the effects of changes in running velocity and slope on the biomechanical factors of the lower limb joints. For this purpose, 15 adult males in their 20s ran according to changes in running speed (2.7, 3.3 m/s) and slope ( -9°, -6°, 0°, 6°, 9°) on the treadmill, and their running characteristics (stride length, stride frequency). The range of motion of the lower limb joint and the vertical ground reaction force were greater in UR (p <.05), and the moment of the lower limb joint, braking force, thrust and load factor was large in DR (p <.05). In joint power, the ankle joint was greater in DR, and hip joint was greater in the UR (p <.05). These results show that the injuries of the ankle joint will be greater than other cases when running DR at a speed of 3.3 m/s.

• Journal of Convergence for Information Technology
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• v.10 no.4
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• pp.25-34
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• 2020

The purpose of this study was to identify its influencing factors of depressive symptoms in postmenopausal middle-aged women though analyzing secondary data. The data of 647 with 40~65 aged women who participated in the Seventh Korea National Health and Nutrition Examination Survey in 2016 were used. The data were analyzed by complex sample independent t-test and multiple linear regression. In multiple linear regression analysis, economic status, subjective health status, perceived stress, smoking, physical activity, and limitation of active had significant effect on depressive symptoms in postmenopausal middle-aged women. These variables explained 36% of the variance in depressive symptoms. The findings suggest that healthcare providers should be considered to these factors when developing intervention strategies to decrease depressive symptoms in postmenopausal middle-aged women.

• Journal of Convergence for Information Technology
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• v.10 no.4
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• pp.65-72
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• 2020

This study examines the supervision competence of supervisor from the comparative perspective of supervisor and supervisee, and investigates the effects of organizational factors on supervisor's supervision competence. For this purpose, data collected from 241 workers at social welfare agencies in Gyeonggi-do were analyzed through t-test and hierarchical regression analysis. The major results of data analysis are as follows. First, supervisors are more positive than supervisees in terms of supervision competence. Second, there is a statistically significant difference between two groups in supervision knowledge and qualities among the subfields of supervision competence. Third, in the case of supervisors, the younger the age and the higher the education level, the more positively they perceive their supervision competence, and agency's supervision support explains supervision competence at the level of △R² = .305 at p> .001. Finally, based on the results of this study, the directions for strengthening the supervision competence were suggested.

• Journal of Convergence for Information Technology
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• v.10 no.4
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• pp.1-10
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• 2020

The performance of the personalized product recommendation system for offline shopping malls is poor compared with the one using online environment information since it is difficult to obtain visitors' characteristic information. In this paper, a mobile robot platform is suggested capable of recommending personalized advertisement using customers' sex and age information provided by Face API of MS Azure Cloud service. The performance of the developed robot is verified through locomotion experiments, and the performance of API used for our robot is tested using sampled images from open Asian FAce Dataset (AFAD). The developed robot could be effective in marketing by providing personalized advertisements at offline shopping malls.

• Journal of Convergence for Information Technology
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• v.10 no.4
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• pp.73-80
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• 2020

The purpose of this study is to find out the usefulness of color contrast program for 50 high school students through comparing the traditional class and the class using the entry software : understanding, utilization, satisfaction, and interest. The results of the study were as follows: First, in the case of the class results, there were no limitations on colors due to materials in the class using the entry software, so students used various colors that match the theory. Second, the activity class using the entry software showed a positive response in terms of utilization, satisfaction, and interest except for the comprehension area, compared to the traditional class using the paper activity. Therefore, this study proved the effectiveness of the practice activity using the entry software in the color management class.

• Journal of Convergence for Information Technology
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• v.10 no.4
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• pp.46-54
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• 2020

This study aims to develop and analyze the performance of a selective option straddle strategy based on forecasted volatility to improve the weakness of typical straddle strategy solely based on negative volatility risk premium. The KOSPI 200 option volatility is forecasted by the SVM model combined with the asymmetric volatility spillover effect. The selective straddle strategy enters option position only when the volatility is forecasted downwardly or sideways. The SVM model is trained for 2008-2014 training period and applied for 2015-2018 testing period. The suggested model showed improved performance, that is, its profit becomes higher and risk becomes lower than the benchmark strategies, and consequently typical performance index, Sharpe Ratio, increases. The suggested model gives option traders guidelines as to when they enter option position.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.41 no.1
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• pp.94-101
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• 2018

With the development of industrial technology and science, production and manufacturing facilities have been enhanced and improved, and the importance of the safety of workers has also been regulated and limited by various safety management methods. As a way to secure the safety of the workers from the production facility, the fail-safe and fool-proof methods are now being applied. Any possible insecure behavior and unsafe conditions can be removed by adopting the standards and specifications that are now secure the safety of workers and equipment. This research analyzes EN ISO 13849-1 international and European standards during CE certification. In order to secure acceptable reduced risks, the risk assessment process of ISO 12100 and the processes for reducing its risk are applied. In the current ISO 13849-1 standard, the criteria for the required performance level PLr (Required Performance Level) for the applicable risk and safety functions through the risk assessment are subjective and not subdivided. Therefore, the evaluation criteria are likely to cause judge's judgement error due to qualitative judgement. This research focuses on evaluation and acceptable performance level setting for the safety circuit of the equipment. We propose an objective and specific evaluation criteria to secure safety, and the proposed evaluation criteria are applied to the case study of the safety circuit for the equipment. In order to secure the safety of the entire safety circuit, the improvement of the MTTFd and DC level related to the SRP/CS (Safety-Related Parts of Control Systems)' lifetime is required for the future research.