• Journal of Korean Society for Geospatial Information Science
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• v.24 no.1
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• pp.43-50
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• 2016

Urbanization in Korea has increased significantly and subsequently, various facilities have been concentrated in urban areas at high speed in accordance with a growing urban population. Accordingly, damages have occurred due to a variety of disasters. In particular, fire damage among the social disasters caused the most severe damage in urban areas along with traffic accidents. 44,432 cases of fire occurred in 2015 in Korea. Due to these accidents, 253 were killed and property damage of 4,50 billion won was generated. However, despite the efforts to reduce a variety of damage, fire danger still remains high. In this regard, this study collected fire data, generated from 2007 to 2014 through the Jinju Fire Department and the National Fire Data System(NFDS) and calculated fire risk by analyzing the clustering of fire cases and facilities in Jinju-si based on the current DB of facilities, offered by the Ministry of Government Administration and Home Affairs. As a result, the risk ratings of fire occurrence were classified as four stages under the standards of the US Society of Fire Protection Engineers(SEPE). Business facilities, entertainment facilities, and automobile facilities were classified as the highest A grade, detached houses, Apartment houses, education facilities, sales facilities, accommodation, set of facilities, medical facilities, industrial facilities, and life service facilities were classified as U grade, and other facilities were classified as EU grade. Finally, hazardous production facilities were classified as BEU grade, the lowest grade. In addition, in the case of setting the standard with loss of life, the highest risk facility was the hazardous production facilities, while in the case of setting the standard with property damage, a set of facilities and industrial facilities showed the highest risk. In this regard, this study is expected to be effectively utilized to establish the fire reduction measures against facilities, distributed in urban space by calculating risk grades regarding the generation frequency, casualties, and property damage, through the classification of fire, occurred in the city, according to the facilities.

• Korean Chemical Engineering Research
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• v.53 no.5
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• pp.557-564
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• 2015

The previous etching, rinsing and drying processes of wafers for MEMS (microelectromechanical system) using SC-$CO_2$ (supercritical-$CO_2$) consists of two steps. Firstly, MEMS-wafers are etched by organic solvent in a separate etching equipment from the high pressure dryer and then moved to the high pressure dryer to rinse and dry them using SC-$CO_2$. We found that the previous two step process could be applied to etch and dry wafers for MEMS but could not confirm the reproducibility through several experiments. We thought the cause of that was the stiction of structures occurring due to vaporization of the etching solvent during moving MEMS wafer to high pressure dryer after etching it outside. In order to improve the structure stiction problem, we designed a continuous process for etching, rinsing and drying MEMS-wafers using SC-$CO_2$ without moving them. And we also wanted to know relations of states of carbon dioxide (gas, liquid, supercritical fluid) to the structure stiction problem. In the case of using gas carbon dioxide (3 MPa, $25^{\circ}C$) as an etching solvent, we could obtain well-treated MEMS-wafers without stiction and confirm the reproducibility of experimental results. The quantity of rinsing solvent used could be also reduced compared with the previous technology. In the case of using liquid carbon dioxide (3 MPa, $5^{\circ}C$, we could not obtain well-treated MEMS-wafers without stiction due to the phase separation of between liquid carbon dioxide and etching co-solvent(acetone). In the case of using SC-$CO_2$ (7.5 Mpa, $40^{\circ}C$), we had as good results as those of the case using gas-$CO_2$. Besides the processing time was shortened compared with that of the case of using gas-$CO_2$.

• Korean Journal of Agricultural Science
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• v.8 no.1
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• pp.90-96
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• 1981

To design more efficient agricultural machinery, the accurately measuring system among many other factors is essential. A light-beam oscillographic recorder is generally used in measuring dynamic strain but it is not compatible with the extremely high speed measuring system such as 1,000 m/s, also is susceptable to damage due to vibration while using the system in field. The recorder used light sensitive paper for strip chart recording. The reading and analysis of data from the strip charts is very cumbersome, errorneous and time consuming. A microcomputer was interfaced with A/D converter, microcomputer program was developed for measuring, system calibration was done and the strain generated from a cantilever beam vibrator was measured. The results are summarized as follows. 1. Microcomputer program was developed to perform strain measuring of agricultural machine elements and could be controled freely the measuring intervals, no. of channels and no. of data. The maximum measuring speed was $62{\mu}s$. 2. Calibration the system was performed with triangle wave generated from a function generator and checked by an oscilloscope. The sampled data were processed using HP 3000 minicomputer of Chungnam National University computer center the graphical results were triangle same as input wave and so the system have been out of phase distorsion and amplitude distorsion. 3. The strain generated from a cantilever beam vibrator which has free vibration period of 0.019 second were measured by the system controlled to have l.0 ms of time interval and its computer output showing vibration curve which is well filted to theoretical value. 4. Using microcomputer on measuring the strain of agricultural machine elements could not only save analyzing time and recording papers but also get excellent adaptation to field experiment, especially in measurement requiring high speed and good precision.

• 대한공업교육학회지
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• v.34 no.2
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• pp.128-160
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• 2009

Narratively I have described interactions between two teachers performing an introduction to the engineering class with various situations such as place, teacher, student and subject. I have specifically illuminated a three-dimensional narrative inquiry space embracing the culture of the university, the college of engineering and the ABEEK(Accreditation Board of Engineering Education of Korea)program. The result of the study is as follows: First, in order to stimulate the students' motivation, the teachers have to make not only their class PowerPoint slides match the size of the classroom, but the content of the slides must be condensed with core concepts. They also should utilized some video clips to empower students' interest in the subject within their classrooms. Second, the teachers should do various class activities in the classroom. Instead of spending most of the class time with his/her explanation, it would be advantageous for the teachers to allow the students to perform a task in class. Third, the teachers should ask their students about assignments which are helping students' understanding of the subject and planning of their future. Lastly, the teachers need to design the mid-term and the final tests inducing the students' motivation. Those tests also must test students' creativity and insight of the subject. Thus, the test should consist of an interpretive exercise and an essay type of item thus reducing the multiple choice types of items. There are several limitations to the study. First it is difficult to generalize what we found here because it is a case study. Second, we could not study in depth the effect of the interaction between the two teachers who were performing the introduction to the engineering course during the academic semester. Third, this study just probed into the difficulties of teaching the course. Hence, we have to understand more by focusing on each issue such as adapting to a new learning environment as a student from abroad, a practical experience boosting the students' interest in the introduction to the engineering course, also a practical experience on process based learning-versus result based learning, and an effective management of the student team presentation etc.

• Journal of Climate Change Research
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• v.4 no.4
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• pp.409-416
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• 2013

Recently, the property damage has been increasing due to climate change in South Korea. While the general public has become more aware of the environmental issues, but the environmental education system has not been able to meet up with the demands of the public. The purpose of this study is to suggest preliminary data which is needed for developing a environmental textbook. A survey was conducted to meet the following requirements. Respondent's level of interest in problems or situations concerning the following eight themes: fundamental science, health and medicine, aerospace engineering, life science, electrical electronics, telecommunication, mineral and energy resources, environment. The data was collected from 139 students in Seoul and Gyeonggi province. The results showed that health and medicine issues interest students the most (49.6%), followed by environment (46.8%). We asked the respondents who were very interested in each question for their reasons, and they answered that environmental issue is related to the improvement of their life quality (53.8%) than their curiosity (38.5%). Students were very interested in the other issues because of just curiosity. Most students (90.6%) said seasonal change was not same each year. 18.0% of respondents replied that they and their friends had experienced climate change. The majority of students (94.2%) thought that they will experience natural disaster blamed on climate change during their life. In other words, climate change is already the day-to-day events of their lives. The majority of their opinions, more then three than ten students(30.9%) said the South Korean government should conduct an energy saving campaign to climate change problems followed by expanding new renewable energy (24.5%), conducting adaptation policies of climate change(22.3 %), introducing of a system as like $CO_2$ emissions trading(20.9%) and so on. There are more Stu- dents (69.1%) who know of new renewable energy than students who don't know it; however, respondents who know the meaning very well were just 18.7% showing that most students dimly know the meaning of new renewable energy.

• Journal of Food Hygiene and Safety
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• v.31 no.3
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• pp.153-166
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• 2016

The purpose of this study was to investigate consumers' perceptions on monosodium L-glutamate (MSG) in social media. Data were collected from Naver blogs and Naver web communities (Korean representative portal web-site), and media reports including comment sections on a Yonhap news website (Korean largest news agency). The results from Naver blogs and Naver web communities showed that it was primarily mentioned MSG-use restaurant reviews, 'MSG-no added' products, its safety, and methods of reducing MSG in food. When TV shows on current affairs, newspaper, or TV news reported uses and side effects of MSG, search volume for MSG has increased in both PC and mobile search engines. Search volume has increased especially when TV shows on current affairs reported it. There are more periods with increased search volume for Mobile than PC. Also, it was mainly commented about safety of MSG, criticism of low-quality foods, abuse of MSG, and distrust of government below the news on the Yonhap news site. The label of MSG-no added products in market emphasized "MSG-free" even though it is allocated as an acceptable daily intake (ADI) not-specified by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). When consumers search for MSG (monosodium L-glutamate) or purchase food on market, they might perceive that 'MSG-no added' products are better. Competent authorities, offices of education and local government provide guidelines based on no added MSG principle and these policies might affect consumers' perceptions. TV program or news program could be a powerful and effective consumer communication channel about MSG through Mobile rather than PC. Therefore media including TV should report item on monosodium L-glutamate with responsibility and information based on scientific background for consumers to get reliable information.

• Journal of Practical Engineering Education
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• v.15 no.1
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• pp.119-126
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• 2023

Today, in order to improve fuel efficiency and dynamic behavior of automobiles, an era of light weight and simplification of automobile parts is being formed. In order to simplify and design and manufacture the shape of the product, various components are integrated. For example, in order to commercialize three products into one product, product processing is occurring to a very narrow area. In the case of existing parts, precision die casting or casting production is used for processing convenience, and the multi-piece method requires a lot of processes and reduces the precision and strength of the parts. It is very advantageous to manufacture integrally to simplify the processing air and secure the strength of the parts, but if a deep and narrow pocket part needs to be processed, it cannot be processed with the equipment's own spindle. To solve a problem, research on cutting processing is being actively conducted, and multi-axis composite processing technology not only solves this problem. It has many advantages, such as being able to cut into composite shapes that have been difficult to flexibly cut through various processes with one machine tool so far. However, the reality is that expensive equipment increases manufacturing costs and lacks engineers who can operate the machine. In the five-axis cutting processing machine, when producing products with deep and narrow sections, the cycle time increases in product production due to the indirectness of tools, and many problems occur in processing. Therefore, dedicated machine tools and multi-axis composite machines should be used. Alternatively, an angle spindle may be used as a special tool capable of multi-axis composite machining of five or more axes in a three-axis machining center. Various and continuous studies are needed in areas such as processing vibration absorption, low heat generation and operational stability, excellent dimensional stability, and strength securing by using the angle spindle.

• Journal of Environmental Health Sciences
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• v.41 no.6
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• pp.449-457
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• 2015

Objectives: In Korea, the system of management of medical waste largely relies on the incineration method. Our study aimed to identify any regional imbalances between the generation and treatment of medical waste, and provide reference data for future policy in Korea. Methods: We analyzed data on the amount of medical waste from 2,000 hospitals in 2012, 2013, and 2014 obtained from the Korea Environment Corporation. In the Arc GIS program (version 10.2.3), the addresses of hospitals and incinerators were transformed into map coordinates. The amount of waste generated by each hospital and the amount incinerated were represented by density and size of a triangle symbol, respectively. Results: As of 2014, the total amount of medical waste from the top 2,000 hospitals was 136,073 tons, out of which about half (49%) was generated in the capital area. Eleven incineration companies (three in the capital area, two in the Chungcheong Provinces area, one in the Jeolla Provinces area, and five in the Gyeongsang Provinces area) treated this waste. For the years 2012, 2013, and 2014, about 60% of the medical waste generated from the hospitals in the capital area was treated within the capital area and about 40% was transported to other areas, especially the Gyeongsang Provinces area, for treatment. On the other hand, about 90% of the medical waste incinerated in the capital area originated from the capital area. Conclusion: Our results suggest a spatial imbalance between the generation and treatment of medical waste in Korea and warrants multilateral policies, including the expansion of on-site treatment, strengthening regulation of the containment of medical wastes, promoting reductions in medical waste and more.

• Journal of the Korean Chemical Society
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• v.46 no.1
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• pp.90-96
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• 2002

The STS contents, emphasized in the 6th curriculum, in the chemistry textbooks(II) were analyzed. The STS contents in textbooks showed average value of 2.7%. The chapter of ‘chemical bond and compound' were included 3.8% of STS contents. And the chapter of ‘atomic structure and periodic table', ‘state of material and solution', ‘science of material', and ‘chemical reaction' contained 3.2%, 2.2%, 1.9%, and 1.9% of STS contents, respectively. When the STS contents were analyzed by STS topics of Piel, the results are as follows; 33.7% on effect of technological developments, 27.5% on environmental quality and utilization of natural source, 19.6% on human engineering, 13.8% on energy, and 5.4% on sociality of science. However, there were no topics on population, space research and national defense. When the STS contents were analyzed by student activities of SATIS, most of the activities were research and case study. There were few field activities of practical investigation, problem solving and decision making, research design and stimulation. There were no activities of role play.

• Korean Journal of Microbiology
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• v.41 no.2
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• pp.105-111
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• 2005

Streptomyces produces many kinds of secondary-metabolites including antibiotics. Screening of a new compound and elucidation of a biosynthetic pathway for the secondary metabolites are very important fields of biology, however, there is a main problem that most of the identified compounds are already researched compounds. To solve these problems, a microarray system that is based on the data related to the biosynthetic genes for secondary-metabolites was designed. For the main contents of DNA microarray, the important genes for the bio-synthesis of aminoglycosides, polyenes group, enediyne group, alpha-glucosidase inhibitors, glycopeptide group, and orthosomycin group were chosen. A DNA microarray with 69 genes that were involved in the bio-synthesis for the antibiotics mentioned above was prepared. The usability of the DNA microarray was confirmed with the chromosomal DNA and total RNA extracted from S. coelicolor whose genomic sequence had already been reported.