• Journal of Ocean Engineering and Technology
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• v.25 no.5
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• pp.27-32
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• 2011

Recently, a ship-shaped barge has been developed to improve the resistance performance, as well as course-keeping capability. However, the stern of the barge is still similar to a box shape, and the vortex generated at the side of the barge creates drag and yaw instability. In order to solve this problem, stern skegs are normally used. The present paper deals with the correlation between the size of the stern skegs and the barge dimensions and hull coefficient. A stern skeg was designed to prevent yaw instability and minimize any additional resistance. The resistance test and course keeping test were performed in the towing tank at Pusan National University. To determine the correlation parameters between the designed stern skeg size and barge dimensions, a parametric study was also performed. Based on the experimental data from five barges, the optimum skeg dimensions were successfully derived. It is expected that the validation of the present study will be carried out by further experiments and computational comparisons in the near future.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.3
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• pp.259-268
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• 2019

Even if only two ships are encountered, a collision may occur due to the mistaken judgment of the positional relationship. In other words, if an officer does not know a target ship's intention, there is always a risk of collision. In this paper, the experiments are conducted to investigate how the intention affects the action of collision avoidance in cooperative and non-cooperative situations. In non-cooperative situation, each ship chooses a course that minimizes costs based on the current situation. That is, it always performs a selfish selection. In a cooperative situation, the information is exchanged with a target ship and a course is selected based on this information. Each ship uses the Distributed Stochastic Search Algorithm so that a next-intended course can be selected by a certain probability and determines the course. In the experimental method, four virtual ships are set up to analyze the action of collision avoidance. Then, using the actual AIS data of eight ships in the strait of Dover, I compared and analyzed the action of collision avoidance in cooperative and non-cooperative situations. As a result of the experiment, the ships showed smooth trajectories in the cooperative situation, but the ship in the non-cooperative situation made frequent big changes to avoid a collision. In the case of the experiment using four ships, there was no collision in the cooperative situation regardless of the size of the safety domain, but a collision occurred between the ships when the size of the safety domain increased in cases of non-cooperation. In the case of experiments using eight ships, it was found that there are optimal parameters for collision avoidance. Also, it was possible to grasp the variation of the sailing distance and the costs according to the combination of the parameters, and it was confirmed that the setting of the parameters can have a great influence on collision avoidance among ships.

• The Journal of the Convergence on Culture Technology
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• v.8 no.6
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• pp.553-560
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• 2022

The research of course-embedded learning evaluation method, which can be used to measure the competency of learners by evaluation of learning outcomes, has been performed for competency-based education in the university. In this paper, we propose an learning evaluation and adaptive feedback model based on learning outcomes, learning subjects, learning concepts graph, and an evaluation matrix. Firstly, we define the layered learning outcomes, a graph of learning subjects and concepts, and two association matric. Secondly, we define algorithms to calculate the level of learning achievement and the learning feedback to learners. We applied the proposed method to a specific course, "Java Programing", to validate the effectiveness of our method. The experimental results show that our proposed method can be useful to measure the learning achievement of learners and provide adaptive feedbacks to them.

• Journal of People, Plants, and Environment
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• v.22 no.1
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• pp.65-73
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• 2019

The purpose of the study was to examine the effects of the Horticulture Job Skill course based on the employment practice model on personal performance indicator of vocational rehabilitation for university students with disabilities. In the first step of this study, an employment practice model was developed by a focus group composed of six specialists from the industry and academia. The second step consisted of selecting the items of personal performance indicator related to horticulture vocational rehabilitation among all items of vocational rehabilitation. The third step was selecting students to participate in the study. The next step was coming up with a pilot instructional design based on the employment practice model. The final step was examining the effects of pilot course (horticulture job skill) based on the employment practice model on personal performance indicator of vocational rehabilitation for university students with disabilities. As a result, there were significant improvements after treatment in the experimental group with indicator 1 (managing) from 1.8±0.155 to 4.2±0.267, indicator 2 (planting) from 1.5±0.114 to 4.45±0.153, indicator 3 (using tool) from 3.2±0.186 to 4.6±0.112, indicator 4 (packing) from 2.05±0.153 to 4.45±0.114, indicator 5 (decorating) from 2.65±0.150 to 5.5±0.114, indicator 6 (cleaning) from 2.85±0.131 to 4.45±0.114, indicator 7 (observing) from 2.4±0.112 to 4.45±0.112, and indicator 8 (laboring) from 2.35±0.109 to 4.1±0.180. However, the control group did not show any significant improvement after 15 weeks of the program. This study determined that the Horticulture Job Skill course based on the employment practice model has an effect on improving the individual performance of vocational rehabilitation for university students with disabilities. Finally, horticulture education-based on the employment practice model will contribute to vocational rehabilitation for university student with disabilities.

• Journal of Korean Academy of Nursing
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• v.13 no.3
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• pp.95-105
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• 1983

The purpose of this study was investigated the effects of education for nursing concept to the nursing students who are not attended to major course of nursing education in nursing college. it is hoped that this education for nursing concept will be contribute to positive nursing conceptualization for nursing students. The data for this study obtained from 118 students in attending college of nursing Ewha womens University(1st year; 62, End year; 56). 1st year students(experimental group) was attended to the education for nursing concept by investigators and 2nd year students(control .group) did not. After then tested to two group: Pre and post test for experimental group and post test only to control group. The results obtained were as follows: 1) In experimental group, pre-test mean score was 116.19(SD 50.46) and post-test mean score was 253.02 (SD 66.56). Therefore post-test mean score was higher than pre-test mean score (p=0.0001). 2) There were different score between the experimental group and control group. Control group was higher(207.58, SD 52.42) than experimental group(116.19, SD 50.46) at the pre-test (p=0.0002), but experimental group(253.02, SD 66.56) was higher than control group. (207 58, SD 52.42) at post-test(p=0.0001). These results implied that early intensive education for nursing concept might have positive effects on nursing conceptualization for nursing students.

• 대한공업교육학회지
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• v.45 no.2
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• pp.1-20
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• 2020

The purpose of this study is to develop an assembly-type liquid level control experimental equipment and a hands-on activity task that can be applied to the class so that students studying the chemical industry can easily understand the liquid level control. For this purpose, the content elements related to liquid level control in the chemical industry practice course of the 2015 revised curriculum was analyzed, a hands-on activity task with an assembly-type liquid level control experimental equipment was and developed. And then, expert verification was also performed and the hands-on activity task was applied to 19 students of S meister high school. The results obtained through this are as follows. First, the existing completion-type liquid level control experimental equipment was explored, and based on this, a new assembly-type liquid level control experimental equipment that can be assembled by students and used for practices was designed and manufactured. Second. by analyzing the contents of the NCS-based 'Chemical Process Maintenance Operation' practical course of the 2015 revised curriculum, learning contents related to level control were extracted. Among the contents related to the level control, the practice with understanding the process flow chart, manufacturing the level control experimental equipment, measuring the flow rate, and checking the level control phenomenon were conducted with the assembly-type liquid level control experimental equipment to systematically learn the level control.

• Nutritional Sciences
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• v.8 no.4
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• pp.205-211
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• 2005

This study examined the time course effects of conjugated linoleic acid (CLA) on the body weight, adipose depots and lipid profiles of ICR male mice using two different sources of fats in the diet Ninety eight mice weighing 25 to 30 g were divided into four groups: beef tallow (BT) and fish oil (FO), beef tallow with CLA supplementation (BTC), and fish oil with CLA supplementation (FOC) group. Eight to nine mice in each group were fed with the experimental diets for 1, 2 or 4 weeks, respectively. All mice were fed experimental diets containing $12\%$ of total dietary fat (w/w) with or without $0.5\%$ CLA (w/w). CLA supplementation did not affect the body weight The weight of epididymal and visceral fats were significantly lower in BTC compared to those in BT groups during the periods examined (p<0.05), whereas they were significantly lower in FOC than those in FO only at 4 weeks (p<0.05). The levels of triglycerides in the plasma were significantly decreased in the BTC group than in BT group throughout the experimental periods (p<0.05). But, FOC was only effective at 4 weeks as compared to FO. The levels of total cholesterol and HDL-C were significantly increased in the BTC than in BT during the entire period (p<0.05), whereas there were no difference between FO and FOC on the levelsof total cholesterol and HDL-C. The levels of free fatty acids (FFA) were significantly decreased in BTC than in BT at 1 and 4weeks and in FOC only at 4 weeks as compared to FO (p<0.05). Taken these results together, CLA was more effective in the beef tallow diet in lowering the epididymal and visceral fat weights and triglyceride level rather than fish oil diet with CLA. Furthermore, the effect became clearer at 4 weeks than at one week of the experiment.

• Journal of Veterinary Science
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• v.22 no.2
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• pp.27.1-27.13
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• 2021

Background: Ozone is an antimicrobial agent that in experimental and case-control studies has been found to exert a positive effect on wound healing. Wild and pet chelonians frequently present insidious wounds exhibiting secondary infections and/or delayed healing. Objectives: Evaluate the effects of topical ozonated sunflower oil on second-intention healing of acute experimental skin wounds in red-eared sliders (Trachemys scripta elegans). Methods: Randomised within-subject controlled study; Group 1 (n = 24) was used to assess clinical healing features; Group 2 (n = 12) was used for histological evaluation in which two sets of wounds were biopsied at 2, 7, 14, 21, 28 and 42 days over the course of the cicatrisation process. A single 6 mm diameter wound was made on each rear limb and topical ozonated (950 peroxide value) and non-ozonated sunflower oil were applied daily for one week on treated and contralateral control wounds, respectively. Results: Mean wound size was significantly lower in the ozone-treated group at day 28 (p < 0.0001) with differences of clinical relevance (74.04% vs. 93.05% reduction of initial wound size). Histologically, the acute inflammatory reaction was enhanced in treated wounds, with significantly higher numbers of heterophils (p = 0.0016), lymphocytes (p < 0.001) and fibroblasts (p < 0.001). Conclusions: Daily topical application of ozonated sunflower oil over the course of one week improved the healing of acute, full-thickness skin wounds in chelonians. This clinical outcome was histologically correlated with an enhanced acute inflammatory reaction, as well as the production and remodelling of collagen fibres.

• Parasites, Hosts and Diseases
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• v.27 no.4
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• pp.249-252
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• 1989

Fibricola cratera is a strigeoid trematode indigenous to North America that, heretofore, was known only to infect wild mammals. Herein, it is reported that an experimental inoculation of a human volunteer produced a patellt infection that lasted 40 months. Symptoms of epigastric discomfort, loose stools and flatulence occurred over the first year of infection and ameliorated thereafter. Eggs per gram of stool were low (${\leq}2$) throughout the course of infection and were not detected by the standard technique of formalin-ether concentration. To monitor infection, the entire stool sample was examined each month after sieving through No. 10 (pore size 2 mm) and 100 (pore size $145{\;}{\mu\textrm{m}}$) sieves and collecting eggs on a No. 325 (pore size $45{\;}{\mu\textrm{m}}$) sieve. This is the first report of a North American strigeoid trematode capable of maturing in a human and is only the second species of strigeoid known to do so. The other species is F. seoulensis which has been implicated in 26 human infections in Korea.

• Korean Journal of Child Studies
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• v.31 no.5
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• pp.167-191
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• 2010

The purpose of this study is to examine how science activities using nonfiction literature affectspreschool children's scientific process skills, attitudes and concepts. For the purposes of this study, two classes, consisting of four and five-year-old children in a kindergarten located in D city were selected. One class was designated as the experimental group and the other as the control group. The experimental group performed science activities using nonfiction literature, while the control group did not. Thisexperimental study was conducted over the course of 8 weeks. Analysis of data was performed by ANCOVA. The results of the posttest indicated that the experimental group which performed science activities using nonfiction literature showed an improvement in their process skills, scientific attitudes and scientific concepts compared with the control group.