• Water for future
• /
• v.27 no.3
• /
• pp.115-121
• /
• 1994

Cohesie sediment movement in estuarine systems is strongly affected by the phenomena of aggregation and flocculation. Aggregation is the process where primary particles are clustered together in tightly-packed formations; flocculation is the process where aggregates and single particles are bonded together to form large particle groups of very low specific density. The size, shape and strength of the flocculants control the rate of deposition and the processes of pollutant exchange between suspended sediments and ambient water. In estuarine waters, suspended sediments above the lutocline form the mobile suspension zone while below the lutocline they form the stationary suspension zone. Suspended particles in the mobile zone are generally in a dispersed state and the controlling forces are the Brownian motion and the turbulent flow fluctuations. In the stationary suspension zone, the driving force is the gravity. This paper discusses the settling and particle flocculation characteristics under quiescient flow conditions. Particles are entering the study domain randomly. Particles in the mobile suspension zone are simulated by using the Smoluchowski's model. Flocs created in the mobil suspension zone are moving into the stationary suspension zone where viscosity and drag effects are important. Utilizing the concepts of the maximum Feret's diameter and the Minkowski's sausage logic, the fractal dimension of the flocs within the stationary suspension is estimated and then compared with results obtained by other studies.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2014.10a
• /
• pp.241-243
• /
• 2014

In this study, that by applying the algorithm of collective intelligence in helping to select the teaching methods and learning methods of learner and teacher, develop a content recommendation system, the teacher and the learner promote effective learning, I have intended to And for this reason can be applied to education recommended system to be applied to a movie or shopping mall recently, at the time of selection, it is appropriate in accordance with the state, such as the level of the learner, learning environment, learners the theme of teaching and learning, and to provide a teaching method and learning method, the learner can to find the learning method appropriate for the user, and a more efficient, Professor system that can save time to design the teaching learning process I developed, The utility and accuracy of the learning content recommendation system developed finally, after the data is accumulated in the use of a continuous schedule of the learner and a teacher, would need to be validated through the rating.

• Journal of the Architectural Institute of Korea Planning & Design
• /
• v.34 no.2
• /
• pp.23-31
• /
• 2018

In recent years, as the development of construction technology and population increase, buildings are becoming more complex and high-rise. These large scale buildings are difficult to secure fire and evacuation safety when fire occurs. So it is necessary to prepare specific measures. According to this situation, in 2011, Republic of Korea officially launched Performance-based Design in "Fire-fighting system Installation business Act". But even 6 years passed since the enforcement, there are still faces manifold problems in the course of implementation. In order to examine the necessary improvements, in this study, I conducted interviews and questionnaires with experts, investigated the improvement items under current laws. And draw up a measures for that items. The subjects of the survey were fire-fighting officer, professional engineer fire fighting, fire protection planner and professor in Daegu. As a result of twice surveys, a total of 19 items are derived. And then compared and analyzed the criteria of overseas countries, and suggested improvement directions for final items. In addition, conducted a third questionnaire survey on the proposed improvement direction to verify the appropriateness of the alternative. The results of this study will be used as basic data to deal with the general problems of performance-based design in future, and further study on each item will be needed.

• Women's Health Nursing
• /
• v.29 no.1
• /
• pp.20-31
• /
• 2023

Purpose: As more newborns have received expanded newborn screening (NBS) for metabolic disorders, the overall number of false-positive results has increased. The purpose of this study was to explore the psychological impacts experienced by mothers related to the NBS process. Methods: An online parenting community in Korea was selected, and questions regarding NBS were collected using web crawling for the period from October 2018 to August 2021. In total, 634 posts were analyzed. The collected unstructured text data were preprocessed, and keyword analysis, topic modeling, and visualization were performed. Results: Of 1,057 words extracted from posts, the top keyword based on 'term frequency-inverse document frequency' values was "hypothyroidism," followed by "discharge," "close examination," "thyroid-stimulating hormone levels," and "jaundice." The top keyword based on the simple frequency of appearance was "XXX hospital," followed by "close examination," "discharge," "breastfeeding," "hypothyroidism," and "professor." As a result of LDA topic modeling, posts related to inborn errors of metabolism (IEMs) were classified into four main themes: "confirmatory tests of IEMs," "mother and newborn with thyroid function problems," "retests of IEMs," and "feeding related to IEMs." Mothers experienced substantial frustration, stress, and anxiety when they received positive NBS results. Conclusion: The online parenting community played an important role in acquiring and sharing information, as well as psychological support related to NBS in newborn mothers. Nurses can use this study's findings to develop timely and evidence-based information for parents whose children receive positive NBS results to reduce the negative psychological impact.

• Journal of the Korean Society of Industry Convergence
• /
• v.27 no.2_2
• /
• pp.475-485
• /
• 2024

In many regions of Korea, including the Four Major Rivers, the seriousness of the problem of algal blooms due to eutrophication of water quality is being raised.In this study, in order to solve these social problems, we manufactured a filter using natural mineral fusion (red illite, zeolite, germanium ceramic, selenium ceramic, carbon ceramic) and independently developed a tank system for green algae experiments to observe and determine the stages of change in water quality. In order to study ways to improve water quality through quantitative analysis, 1 ton of severely polluted green algae water from the Nak dong River region was stored in a water tank and exposed to ultraviolet rays in the same environment as the Nak dong River. Then, the same environment as the Nak dong River was created. The results were derived from a 5-week water quality test. The results of this experiment confirmed that green-colored cyano bacteria were significantly reduced just by the turbidity results. The results were obtained through a request to the Korea Testing & Research Institute located in Changwon-si, Gyeong sang nam-do. CI-(chlorine ion) and NH3-N(ammonia nitrogen) had the effect of saving every week. The device used in this study was made of natural minerals free of heavy metals that are harmless to the human body and nature through long-term consideration and exploration to kill and prevent various strains living in water. Green purification system using natural hydrogen generating mineral filter were effective a non-chemical and physical methods. The results of this study are one way to contribute to the serious problems caused by green algae in many countries, and will contribute to the water quality environment by preventing the waste of environmental resources, improving the health of the people, and increasing the ability to purify environmental water quality at home and abroad.

• Journal of Intelligence and Information Systems
• /
• v.14 no.2
• /
• pp.137-156
• /
• 2008

The purpose of this study is to implement evaluation on domestic cyber University web site to analyze web usability and web accessibility in order to present how much cyber University provides various personalized services and qualitative contents to users on web site. And also with this result, I hope to contribute in qualitative development of web site and reliability of remote education. For this purpose, I developed checklist suitable to remote University by applying SM-ABCDE assessment method of Moonhyeongnam, the professor in Sookmyung Women's University, and implemented evaluation on web sites of 17 cyber University over the five aspects of attraction, business, contents, design, and engineering. As the result of this study, it was found that Busan Digital University was best in the respect of attraction, both Kyunghee Cyber University and Cyber University of foreign studies were best in the respect of business, Kyunghee University was best in the respect of contents, and Hanyang Cyber University was best in the respect of design. It was also evaluated in the comprehensive view and the order was found that Kyunghee Cyber University, Busan Cyber University, and Hanyang Cyber University. However in the respect of engineering, it came out that all the sites did not observe the regulation on web accessibility. If domestic Cyber Universities are to observe the regulation on web accessibility with the long term view, on the base of this study, web usability would be increasing. Then they can secure various classes of customers as well as ordinary people so that they will be able to take the real place of educational institution orienting the most advanced educational method in the society of knowledge and information in addition to advance in themselves.

• Journal of the Korea Society of Computer and Information
• /
• v.28 no.3
• /
• pp.91-100
• /
• 2023

This study is a case study comparing and examining the effects of non-face-to-face(NFTF) classes in the 2021-2 semester and face-to-face(FTF) classes in the 2022-2 semester on learning immersion, learning stress, and learning satisfaction. The learning immersion and learning satisfaction of 240 students were analyzed in NFTF and FTF classes of department S of C junior college where the same textbook, same subject, and same professor were taught. For data processing, SPSS Ver. 23.0 was used. The data is used to measure reliability by Cronbach's α, t-test, Pearson's correlation coefficient, and multiple regression analysis. The results of this study are as follows. First, learners' learning immersion was higher in FTF than NFTF classes among engineering major subjects. Second, it was found that there was a difference in learning stress according to the types of FTF and NFTF classes in engineering major subjects. Third, it was found that there were differences in practice content, communication, and task performance of sub-factors of learning satisfaction according to FTF and NFTF class types in engineering major subjects. In conclusion, it was found that FTF classes had a more positive effect on learning immersion and satisfaction, and NFTF classes had a more negative effect on learning stress.

• 전자공학회논문지 IE
• /
• v.47 no.1
• /
• pp.22-33
• /
• 2010

The main purpose of this study was to develope a reflective journal and examine its effects on student's academic achievement and self-regulated learning strategies. For this study, 'a structured reflective journal' was designed through the steps of systems approach with the purpose of enhancing student's academic achievement and self-regulated learning strategies, especially meta-cognition and critical thinking. The reflective journal used in this study contained the constructive elements of (1) self-evaluation with 5 likert scale, (2) learning essay, (3) dialogue with peers, and (4) dialogue with professor. A total of 94 freshmen enrolled in one of two sections of the engineering courses(theory-based class and experiment and practice-based class) participated in the study for 8 weeks. A pre-test-post-test design was used to examine the effects of the application of reflective journal on student's achievement and self-regulated learning strategies. For the result, analysis of covariance was conducted to determine whether there were any academic achievement differences and self-regulated learning strategy differences. The results suggested that students were taking advantages of the reflective journal, and there were statistically significant differences in academic achievement in the experiment and practice-based class and self-regulated learning strategies in both classes.

• International Journal of Highway Engineering
• /
• v.12 no.1
• /
• pp.79-86
• /
• 2010

Cold in-place recycling (CIR) using emulsified asphalt or foamed asphalt has become a more common practice in rehabilitating the existing asphalt pavement due to its cost effectiveness and the conservation of paving materials. As CIR continues to evolve, the engineered emulsified asphalt was developed to improve the field performances such as coating, raveling, retained stability value and curing time. The main objective of this research is to compare the laboratory responses of the engineered emulsified asphalt (CIR-EE) mixtures against the foamed asphalt (CIR-foam) mixtures using the reclaimed asphalt pavement (RAP)materials collected from the CIR project on U.S. 20 Highway in Iowa. Based on the visual observation of laboratory specimens, the engineered emulsified asphalt coated the RAP materials better than the foamed asphalt because the foamed asphalt is to create a mastic mixture structure rather than coating RAP materials. Given the same compaction effort, CIR-EE specimens exhibited lesser density than CIR-foam specimens. Both Marshall stability and indirect tensile strength of CIR-EE specimens were about same as those of CIR-foam specimens. However, Marshall stability and indirect tensile strength of the vacuum-saturated wet specimens of CIR-EE mixtures were higher than those of CIR-foam mixtures. After four hours of curing in the room temperature, the CIR-EE specimens showed less raveling than the CIR-foam specimens. On the basis of test results, it can be concluded that the CIR-EE mixtures is less susceptible to moisture and more raveling resistant than CIR-foam mixtures.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.4 no.4
• /
• pp.43-61
• /
• 1981

Interest in the Quality of working life is spreading rapidly and the phrase has entered the popular vocabulary. That this should be so is probably due in large measure to changes in the values of society, nowadays accelerated as never before by the concerns and demands of younger people. But however topical the concept has become, there is very little agreement on its definition. Rather, the term appears to have become a kind of depository for a variety of sometimes contradictory meanings attributed to it by different groups. A list of all the elements it if held to cover would include availability and security of employment, adaquate income, safe and pleasant physical working conditions, reasonable hours of work, equitable treatment and democracy in the workplace, the possibility of self-development, control over one's work, a sense of pride in craftsmanship or product, wider career choices, and flexibility in matters such as the time of starting work, the number of working days in the week, Job sharing and so on altogether an array that encompasses a variety of traditional aspirations and many new ones reflecting the entry into the post industrial era. The term "quality of working life" was introduced by professor Louis E. Davis and his colleagues in the late 1960s to call attention to the prevailing and needlessly poor quality of life at the workplace. In their usage it referred to the quality of the relationship between the worker and his working environment as a whole, and was intended to emphasize the human dimension so often forgotten among the technical and economic factors in job design. Treating workers as if they were elements or cogs in the production process is not only an affront to the dignity of human life, but is also a serious underestimation of the human capabilities needed to operate more advanced technologies. When tasks demand high levels of vigilence, technical problem-solving skills, self initiated behavior, and social and communication skills. it is imperative that our concepts of man be of requisite complexity. Our aim is not just to protect the worker's life and health but to give them an informal interest in their job and opportunity to express their views and exercise control over everything that affects their working life. Certainly, so far as his work is concerned, a man must feel better protected but he must also have a greater feeling of freedom and responsibility. Something parallel but wholly different if happening in Europe, industrial democracy. What has happened in Europe has been discrete, fixed, finalized, and legalized. Those developing centuries driving toward industrialization like R.O.K, shall have to bear in mind the human complexity in processing and designing the work and its environment. Increasing attention is needed to the contradiction between autocratic rule at the workplace and democratic rights in society.n society.