• Journal of Internet Computing and Services
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• v.22 no.2
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• pp.59-68
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• 2021

As artificial intelligence(AI) technologies, which have made rapid growth recently, began to be applied to the marine environment such as ships, there have been active researches on the application of CNN-based models specialized for digital videos. In E-Navigation service, which is combined with various technologies to detect floating objects of clash risk to reduce human errors and prevent fires inside ships, real-time processing is of huge importance. More functions added, however, mean a need for high-performance processes, which raises prices and poses a cost burden on shipowners. This study thus set out to propose a method capable of processing information at a high rate while maintaining the accuracy by applying Quantization techniques of a deep learning model. First, videos were pre-processed fit for the detection of floating matters in the sea to ensure the efficient transmission of video data to the deep learning entry. Secondly, the quantization technique, one of lightweight techniques for a deep learning model, was applied to reduce the usage rate of memory and increase the processing speed. Finally, the proposed deep learning model to which video pre-processing and quantization were applied was applied to various embedded boards to measure its accuracy and processing speed and test its performance. The proposed method was able to reduce the usage of memory capacity four times and improve the processing speed about four to five times while maintaining the old accuracy of recognition.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.52-63
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• 2019

Biased performance implications are common in conducting empirical analysis on leading firms in strategic management field. Venture businesses in which successful and failing firms in the future are mixed in the present could provide a better discriminative result for examining the determinants of performance. We suggest hypotheses on how competitive strategy, CEO characteristics, and their interactions affect firm performance. We examine these hypotheses through empirical analyses on the basis of a survey collected from 387 venture businesses in order to assure the validity of strategic management theories by using more deviated data. Empirical results show that innovative differentiation from competitive strategies affects firm performance and innovativeness and long-term orientation from CEO characteristics affect firm performance. According to the results of the interaction analyses between competitive strategies and CEO characteristics, cost-leadership and marketing differentiation strategies have combination effects with risk taking, innovativeness, and long-term orientation, while innovative differentiation strategy has no combination effects with risk taking, innovativeness, and long-term orientation. We conclude that cost-leadership and marketing differentiation strategies have no direct effect on firm performance but have combination effects with CEO characteristics, while innovative differentiation strategy has direct effect on firm performance but has no combination effect. Our primary contribution is that we test and confirm that the fit between competitive strategies and CEO characteristics are an important consideration to increase firm performance in venture businesses.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.2
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• pp.130-143
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• 2019

The purpose of this study is to identify factors of 25~36 months old infant's happiness and to develop a scale to measure infant happiness. The subjects were 250 infants aged 25~36 months. The results of this study are as follows: First, the components and items of infant's happiness scale selected through the literature, the previous measurement tool, and the focus group interview were 8 components and 29 items. The items were composed of 4 items of problem behavior, 4 items of achievement through immersion, 4 items of relationship with friends, 4 items of relationship with teacher, 3 items of physical environment, 4 items of positive emotion, 3 items of negative emotion, and 3 items of health. Second, as a result of validation of validity for infant's happiness scale, the item fit was confirmed with CFI=0.89, TLI=0.88, and RMR=0.05. Also, the construct validity was confirmed with convergent validity and discriminant validity. The concurrent validity was significantly correlated with the components of the previously developed measurement tools, and the reliability was appeared with 0.71-0.89. The infant's happiness scale developed in this study ensured reliability and validity as a measurement to measure infant happiness. Therefore, this scale is expected to be used as a major test tool to develope and verify a program for promoting infant happiness.

• Journal of Ocean Engineering and Technology
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• v.33 no.2
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• pp.168-177
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• 2019

KRISO (Korea Research Institute of Ship & Ocean Engineering) started a project to develop the core algorithms for autonomous intervention using an underwater robot in 2017. This paper introduces the development of the robot platform for the core algorithms, which is an ROV (Remotely Operated Vehicle) type with one 7-function manipulator. Before the detailed design of the robot platform, the 7E-MINI arm of the ECA Group was selected as the manipulator. It is an electrical type, with a weight of 51 kg in air (30 kg in water) and a full reach of 1.4 m. To design a platform with a small size and light weight to fit in a water tank, the medium-size manipulator was placed on the center of platform, and the structural analysis of the body frame was conducted by ABAQUS. The robot had an IMU (Inertial Measurement Unit), a DVL (Doppler Velocity Log), and a depth sensor for measuring the underwater position and attitude. To control the robot motion, eight thrusters were installed, four for vertical and the rest for horizontal motion. The operation system was composed of an on-board control station and operation S/W. The former included devices such as a 300 VDC power supplier, Fiber-Optic (F/O) to Ethernet communication converter, and main control PC. The latter was developed using an ROS (Robot Operation System) based on Linux. The basic performance of the manufactured robot platform was verified through a water tank test, where the robot was manually operated using a joystick, and the robot motion and attitude variation that resulted from the manipulator movement were closely observed.

• Journal of Convergence for Information Technology
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• v.9 no.9
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• pp.219-228
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• 2019

The purpose of this study was to develop a tool to assess the job satisfaction of dental hygienists and to evaluate the validity and reliability of the dental hygienist. A total of 54 items were translated into 24 items through content validity and content analysis. The results of this study are as follows: overall satisfaction, income, patient relations, professional time, personal time, Practice Management, Delivery of Care and co-worker relations were classified by exploratory factor analysis. The fit of the model through confirmatory factor analysis generally met the criteria. As a result of the internal consistency test, Cronbach's ${\alpha}$ was found to be a reliable measure of measurement, with an overall satisfaction of 0.918, an income of 0.833, a patient relationship of 0.804, an occupational time of 0.675, a personal time of 0.939, a work practice of 0.739, The validity and reliability of the dental hygienist 's job satisfaction measurement tool were verified to be appropriate. It can be used to study the job satisfaction of dental hygienist in the future.

• Journal of Food Hygiene and Safety
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• v.34 no.2
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• pp.199-204
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• 2019

This study aimed to generate a probability distribution model based on temperature data of frozen food storage facility as input variables for microbial risk assessment (MRA). We visited 8 food-handling businesses to collect temperature data from their cold storage warehouses. The overall mean temperature inside the storage facilities was $-20.48{\pm}3.08^{\circ}C$, with 20.4% of the facilities having above $-18^{\circ}C$, with minimum and maximum temperature values of -10.3 and $-25.80^{\circ}C$ respectively. Temperature distributions by space locations of natural and forced convection were $-22.57{\pm}0.84$ and $-17.81{\pm}1.47^{\circ}C$, $-22.49{\pm}1.05$ and $-17.94{\pm}1.44^{\circ}C$, and $-22.68{\pm}1.03$ and $-18.08{\pm}1.42^{\circ}C$ in the upper (2.4~4 m), middle (1.5~2.4 m), and lower (0.7~1.5 m) shelves, respectively. Probability distributions from the temperature data were obtained using the program @RISK. Statistical ranking was determined using goodness of fit to determine the probability distribution model. Our results show that a log-normal distribution [5.9731, 3.3483, shift (-26.4281)] is most appropriate for relative MRA conduction.

• 한국체육학회지인문사회과학편
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• v.58 no.1
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• pp.295-308
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• 2019

The purpose of the present study is to apply a health belief model to the serious perception of an increase in youth obesity, and to develop and validate a measurement tool for youth obesity prevention among this group who are experiencing increasing rates of obesity. The specific goals of this study are to 1) apply a health belief model to develop a measurement tool for obesity prevention among youth who are seeing rising rates of obesity, and 2) provide an integrated validation procedure and foundation for developing this measurement tool. A total of 1801 high school students[sample1: 902(male:464,female:438); sample2: 899(male:464,female:438)] were recruited and collected data from 12 high school in Seoul and Kyonggi area. For this study the analytic framework of unified validity was developed which can comprehensively reflect unified validity be Messick(1995), framework for conducting a strong program of construct validation by Benson(1998), the unified validity implementation method of Rasch model suggested by Wolfe and Smith(2007a, 2007b). Furthermore, after dividing the developed analytic framework into each stage(the substantive domain), the evidence of validity of Youth Obesity Prevention Scale(YOPS) applying Health Belief Model was systematically suggested. The YOPS suggested the evidence about the substantive domain of unified validity. The developed YOPS was consist of Susceptibility, Severity, Benefits, Barriers and Cues to Action. After 3 stage in substantive domain, the components of YOPS(5factors and 28items) satisfied the unidimensionality, and the 5 point Likert scale had the significant discrimination of the respondents' response.

• Journal of Life Science
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• v.30 no.12
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• pp.1101-1108
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• 2020

Tartary buckwheat is a grain with many flavonoids, such as rutin, quercetin, kaempferol, and myricetin. This study aimed to optimize extraction conditions to maximize the rutin, quercetin, and myricetin contents of tartary buckwheat sprout extracts using response surface methodology. A BoxBehnken design containing 15 experiments was employed to evaluate the effects of extraction conditions, such as temperature (X1, 50~70℃), extraction time (X2, 5~9 hr), and ethanol concentration (X3, 60~90%). The coefficients of determination (R2) for all the dependent variables (extraction temperature, extraction time, and extraction ethanol concentration) were determined to be over 0.95, indicating significance. The p-value of the model in lack of fit was over 0.1 than means, indicating that the model was well predicted. The optimal extraction conditions for rutin, quercetin, and myricetin contents were obtained at X1 = 51.03, X2 = 6.62, and X3 = 69.16, respectively. Under these optimal conditions, the predicted rutin, quercetin, and myricetin contents were 808.467 ㎍/ml, 193.296 ㎍/ml, and 37.360 ㎍/ml, respectively. For the validation of the model, ten experiments were performed and the experimental rutin and quercetin contents were measured at 802.84±8.49 ㎍/ml, 193.76±2.80 ㎍/ml, and 34.84±0.43 ㎍/ml, respectively. The experimental rutin and quercetin contents were similar to the predicted contents, but the experimental myricetin content was lower than predicted.

• Journal of Korean Society of Forest Science
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• v.109 no.4
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• pp.468-476
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• 2020

we developed a stand density management diagram for Quercus variabilis in order to predict the final cutting ages of coppice forests based on management objectives. The sample data were classified into two groups: 603 data points for analysis and 113 data points for verification. Using these data, a stand density management diagram was constructed and a goodness-of-fit test was performed. The explanatory power (R2) of the constituent models for the stand density management diagram was 0.732 for the equivalent height curve and 0.990 for the equivalent diameter curve. According to the analysis of the final cutting age rangeof the highest production, the final cutting ages for 900 buds remaining per hectare was 42-44 years, and that for the 1,800 buds remaining per hectare was 38-42 years. With the third-grade log set as the production target, the final cutting age range with site index 16 and 14 was 25-28 years and 29-33 years, respectively. The results of this study provide baseline data for establishing a management plan for Q. variabilis coppice stands.

• (The) Korean Journal of Educational Psychology
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• v.28 no.1
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• pp.23-39
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• 2014

The goal of this study was to examine the relationship among students' personal variables(Korean language abilities, self-efficacy, student-teacher attachment relationships), teacher variable(perceptions of multi-cultural education) affecting on multi-cultural students' school adjustment. Structural equation modeling was performed to test the mediating role of self-efficacy and student-teacher attachment affecting multi-cultural students' school adjustment. 336 elementary students and their matching 264 elementary school teachers were participated for this study. The model fit for this study model was acceptable, =280.024, df=98, CFI=.930, RMSEA = .074. The results revealed that teacher's perceptions on multi-cultural education significantly related with student-teacher relationships. However, Korean language ability did not directly affect the school adjustment for multi-cultural background students. That is, self-efficacy and student-teacher relationships mediated between Korean language ability and school adjustment. Moreover student-teacher relationships seem to be the key mediating factor between other research variables and school adjustment. Further considerations and future directions based on results were discussed.