• Journal of the Korean Society of Safety
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• v.34 no.4
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• pp.22-31
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• 2019

The flammable liquid conductivity is an important factor in determining the generation of electrostatic in fire and explosion hazardous areas, so it is necessary to study the physical properties of flammable liquids. In particular, the relevant liquid conductivity in the process of handling flammable liquids in relation to the risk assessment and risk control in fire and explosion hazard areas, such as chemical plants, is classified as a main evaluation item according to the IEC standard, and it is necessary to have flammable liquid conductivity measuring devices and related data are required depending on the handling conditions of the material, such as temperature and mixing ratio for preventing the fire and explosion related to electrostatic. In addition, IEC 60079-32-2 [Explosive Atmospheres-Part 32-2 (Electrostatic hazards-Tests)] refers to the measuring device standard and the conductivity of a single substance. It was concluded that there is no measurement data according to the handling conditions such as mixing ratio of flammable liquid and temperature together with the use and measurement examples. We have developed the measurement reliability by improving the structure, material and measurement method of measuring device by referring to the IEC standard. We have developed a measurement device that is developed and manufactured by itself. The test results of flammable liquid conductivity measurement and the data of the NFPA 77 (Recommended Practice on Static Electricity) Annex B Table B.2 Static Electric Characteristic of Liquids were compared and verified by conducting the conductivity measurement of the flammable liquid handled in the fire and explosion hazardous place by using Measuring / Data Acquisition / Processing / PC Communication. It will contribute to the prevention of static electricity related disaster by taking preliminary measures for fire and explosion prevention by providing technical guidance for static electricity risk assessment and risk control through flammable liquid conductivity measurement experiment. In addition, based on the experimental results, it is possible to create a big data base by constructing electrostatic physical characteristic data of flammable liquids by process and material. Also, it is analyzed that it will contribute to the foundation composition for adding the specific information of conductivity of flammable liquid to the physical and chemical characteristics of MSDS.

• Journal of the Korea Society for Simulation
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• v.28 no.3
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• pp.41-48
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• 2019

In modern-war campaign, precision-guided missiles are dominantly used to minimize the collateral damage. Imaging infrared seekers are widely applied for the precise guidance. Due to the high cost of the infrared detector, the cost for the one-shot weapon's test is a burden for the development. To reduce the test cost, a simulation method including imagery tracking is required, which is so-called integrated-flight simulation(IFS). The synthetic image generation(SIG)-based simulation method is typically used, which however cannot represent various environmental and target conditions. In this paper, a new IFS method is proposed using on-sight measured image to overcome the limitations of the SIG-based IFS(SIIFS). The target image acquired at the launching sight has been used only for checking the performance criteria of the image tracker and has not been tried for IFS since it has low resolution and little information. The study described in this paper, however, shows that the on-sight image-based IFS can predict the pre- and mid-course flight performance quite similarly and is very useful for the flight test analysis.

• Journal of the Korean GEO-environmental Society
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• v.20 no.11
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• pp.11-22
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• 2019

Limit state design (LSD) and allowable stress design (ASD) are two main types of soil nailing design methodologies. In the LSD method, stability is determined by applying individual coefficients to ground strength, working load and etc. The ASD method calculates the safety factor and compares it with the minimum safety factor to determine the stability. The global design trend of soil nailing system is changing from the ASD method to the LSD method. The design method in Korea still adopts the ASD philosophy while others mostly do the limit state design. In this study, four soil nail design methods, 'FHWA GEC 7' in U.S. (2015), 'Clouterre' in France (1991), 'Soil nailing - best practice guidance' in U.K. (2005), 'Geoguide 7' in Hongkong (2008), and 'Design guide for slope in construction work' in Korea (2016) were applied to the evaluation of the stability and the results were analyzed comparatively in brief. It is revealed that the design method of 'the overall stability of soil nail walls' in Korea is the most conservative and next those by FHWA, Clouterre and CIRIA become more conservative in order. However, the difference of results obtained from FHWA and Clouterre is negligible. Also, this study found out that efforts to improve domestic design criterion are needed.

• Journal of the Korea Convergence Society
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• v.12 no.1
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• pp.153-161
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• 2021

The exterior color of the building reflects its style. With the advancement of the 'Village Art' project in South Korea, many villages have gradually developed into tourist attractions. Therefore, it is also important to distinguish between residents' lifestyles and tourist needs through architectural color design. This article first investigates the literature and analyzes the use function of the building and the role of the exterior color in the villages. Secondly, the four types of buildings in Huinnyeoul Culture Village: residential, commercial, leisure, and public toilets are investigated as the research objects. Analyze through the KSCA color measurement analysis system and questionnaire survey, and propose a color plan for the exterior of the building. Research results: First, the main color area of the outer wall of the residential building should be the largest, with a tendency of high brightness and low saturation. Second, small buildings with high chroma in the recreation area can be used as visual guidance.Third, the buildings in the commercial area are mainly of high brightness, high chroma, and multi-hue. Fourth, the main color of the bathroom is the main color of the residential area and the leisure area, which can provide a sense of visual stability.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.697-706
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• 2021

The purpose of this study is to find out whether the many start-up support programs provided by a college can actually help students start a business, and to discuss what role colleges should have as facilitators of student entrepreneurship. To this end, a qualitative study was conducted with seven students who wished to start a business by utilizing start-up education and support programs provided by College Y. As a result of the study, the participants first mentioned parallel and administrative inefficiency in entrepreneurship and the entrepreneurship programs. Second, the implications for the role of colleges in fostering start-up content are systematic planning and guidance for start-up programs operated by the college, concise administrative procedures, mentoring in various start-up items, and securing a test market. It can be said that the concept of a common office in which students can work together is necessary. The study is significant in that it can help to establish a start-up support plan by suggesting what role colleges should play in relation to entrepreneurship, but its limitation is that its scope includes only one specific major.

• Journal of Science Education
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• v.44 no.3
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• pp.331-344
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• 2020

This study aims to find meaningful implications for the development of Korean elementary school math education courses and textbooks by comparing and analyzing the number and arithmetic areas of Korean and Canadian math textbooks in fifth and sixth grades. To this end, the textbook composition system of Korean and Canadian elementary schools was compared and analyzed, and the number and timing of introduction of math textbooks and math textbooks by grade, and the number in fifth and sixth grade and the learning contents of math textbooks were compared and analyzed. The following conclusions were obtained from this study: First, it is necessary to organize a textbook that can solve the problem in an integrated way by introducing the learned mathematical concepts and computations naturally in the context of problems closely related to real life, regardless of the type of private calculation or mathematics area. Second, it is necessary to organize questions using materials such as real photography and mathematics, science, technology, engineering, art, etc. and to organize textbooks that make people feel the necessity and usefulness of mathematics. Third, sufficient learning of the principles of mathematics through the use of various actual teaching aids and mathematical models, and the construction of textbooks focusing on problem-solving strategies using engineering tools are needed. Fourth, in-depth discussions are needed on the timing of learning guidance for fractions and minority learning or how to organize and develop learning content.

• The Journal of the Korea Contents Association
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• v.21 no.1
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• pp.639-648
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• 2021

This study aimed to investigate the effects a strengths-based group counselling program had on self-esteem and career maturity of adolescents under probation. The subjects of the study were female adolescents under probation in Gwangju and were categorized into two groups: experiment group and control group consisting of 15 respectively. As a result, it was discovered that the strengths-based group counselling program had positive effects on enhancement of general and social self-esteem in the subjects while it did not have statistically significant effects on enhancement of family self-esteem. It indicates that positive relationship with parents and recovery of family functions should be encouraged to enhance the family self-esteem. Also, the strengths-based group counselling program had positive effects on planning, self-understanding, career knowledge and career preparation areas relating to career maturity while it did not have statistically significant effects on independence. It shows that to encourage the subjects to be independently prepared for career, family and society should provide more specific support for career guidance. Based on the results above, it was suggested that the strengths-based group counselling program had significant effects on self-esteem and career maturity of the subjects under probation. In conclusion, to encourage adolescents under probation to respect themselves and others, specifically plan their career and grow to be reliable and mature adults, further research on the strengths-based group counselling program is needed and diverse strategies including specific support through mentor service of college students should be developed.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.34 no.5
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• pp.301-313
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• 2021

Theoretical background for the meaning of various piezoelectric properties can be easily found in a number of textbooks and academic papers. In contrast, how they are actually measured and characterized are rarely described, though this information would be the most important especially to the researchers who just started working on the field. It follows that this report was intended to provide a practical guidance for measuring basic but essential properties of ferroelectric-based piezoelectric materials. The discussion begins with how to measurement dielectric properties such as dielectric permittivity and loss (dissipation factor), followed by piezoelectric properties such as piezoelectric constants, electromechanical coupling factor, and quality factor as well as ferroelectric features, i.e., electric field dependent polarization hysteresis. Though our discussion here is limited to the techniques that are already well-standardized, it is expected to make a seed to be developed into more challenging and creative ones.

• Journal of Food Hygiene and Safety
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• v.36 no.3
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• pp.257-263
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• 2021

For this survey, PCR (polymerase chain reaction) testing was conducted using 14 species-specific primers to monitor the labeling of allergy-causing substances in various foods. Sixty samples from stationary stores near elementary schools and imported confectionery shops were tested, including snacks, candies, and chocolate. Allergens of milk, wheat, eggs, tomatoes, almonds and peanuts were detected in 30 cases (50.0%). In addition, many products were detected as either containing unlabeled substances or not showing allergen-related information and labeling in Korean. In order to ensure that consumers are able to purchase products safely and securely, a system for thorough guidance and monitoring of allergen-related labeling by domestic manufacturing and processing companies and import-related companies is required.

• Journal of Information Technology Applications and Management
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• v.28 no.3
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• pp.59-75
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• 2021

This study aims to establish a foundation for autonomous driving on campus and communication of abundant university information in the HCI environment in a VR environment where college freshmen can freely travel around campus facilities. The purpose of this study is to develop a three-dimensional VR-style campus tour system to establish a media environment to provide abundant university information guidance services to freshmen in non-face-to-face situations. This study designed a three-dimensional virtual reality campus tour system to solve the problem of discontinuity in which VR360 filming space does not lead to space like reality, and to solve many problems of expertise in VR technology by constructing an integrated production environment of tour system. We aim to solve the problem of inefficiency, which requires a large amount of momentum in virtual space, by constructing a GUI that utilizes the motion of the field of view focus. The campus environment was designed as a three-dimensional virtual reality using a three-dimensional graphic design. In non-face-to-face situations, college freshmen freely transformed the HMD VR device, smartphone, FPS operation mode of the gyroscope sensor. The design elements of the three-dimensional virtual reality campus tour system were classified as ①Visualization of factual experiences, ②Continuity of space movement, ③Operation, automatic operation mode, ④Natural landscape animation, ⑤Animation according to wind direction, ⑥Actual space movement mode, ⑦Informatization of spatial understanding, ⑧GUI by experience environment, ⑨Text GUI by building, ⑩VR360, 3D360 Studio Environment, ⑪Three-dimensional virtual space coupling block module, ⑫3D360-3D Virtual Space Transmedia Zone, ⑬Transformable GUI(VR Device Dual Viewer-Gyro Sensor Full Viewer-FPS Operation Viewer) and an integrated production environment was established with each element. It is launched online (http://vautu.com/u1) by constructing a GUI for free driving mode and college information screens to adapt to college life for freshmen, and designing an environment that can be used simultaneously by current media such as PCs, Android, and iPads. Therefore, it conducted user research, held a development presentation, a forum on excellence in university innovation support projects, and applied it as a system on the website of a particular university. College freshmen will be able to experience university information directly from the web and app to the virtual reality campus environment.