• Korean Membrane Journal
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• v.7 no.1
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• pp.1-18
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• 2005

The permeate flux decline due to membrane fouling can be addressed using a variety of theoretical stand-points. Judicious selection of an appropriate theory is a key toward successful prediction of the permeate flux. The essential criterion f3r such a decision appears to be a detailed characterization of the feed solution and membrane properties. Modem theories are capable of accurately predicting several properties of colloidal systems that are important in membrane separation processes from fundamental information pertaining to the particle size, charge, and solution ionic strength. Based on such information, it is relatively straight-forward to determine the properties of the concentrated colloidal dispersion in a polarized layer or the cake layer properties. Incorporation of such information in the framework of the standard theories of membrane filtration, namely, the convective diffusion equation coupled with an appropriate permeate transport model, can lead to reasonably accurate prediction of the permeate flux due to colloidal fouling. The schematic of the essential approach has been delineated in Figure 5. The modern approaches based on appropriate cell models appear to predict the permeate flux behavior in crossflow membrane filtration processes quite accurately without invoking novel theoretical descriptions of particle back transport mechanisms or depending on adjust-able parameters. Such agreements have been observed for a wide range of particle size ranging from small proteins like BSA (diameter ${\~}$6 nm) to latex suspensions (diameter ${\~}1\;{\mu}m$). There we, however, several areas that need further exploration. Some of these include: 1) A clear mechanistic description of the cake formation mechanisms that clearly identifies the disorder to order transition point in different colloidal systems. 2) Determining the structure of a cake layer based on the interparticle and hydrodynamic interactions instead of assuming a fixed geometrical structure on the basis of cell models. 3) Performing well controlled experiments where the cake deposition mechanism can be observed for small colloidal particles (< $1\;{\mu}m$). 4) A clear mechanistic description of the critical operating conditions (for instance, critical pressure) which can minimize the propensity of colloidal membrane fluting. 5) Developing theoretical approaches to account for polydisperse systems that can render the models capable of handing realistic feed solutions typically encountered in diverse applications of membrane filtration.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.5
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• pp.484-491
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• 2007

Numerical experiments using a numerical wave tank have been performed to verier the nonlinear interaction between monochromatic waves and a submerged horizontal plate. As a model for numerical wave tank, we used a higher-order Boundary Element Method(BEM) based on fully nonlinear potential flow theory and CADMAS-SURF for solving Navier Stokes equations and exact free surface conditions. Both nonlinear models are able to predict the higher harmonic generation in the shallow water region over a submerged horizontal plate. CADMAS-SURF, which involves the viscous effect, can evaluate the higher harmonic generation by flow separation and vortices at the each ends of plate. The comparison of reflection and transmission coefficients with experimental results(Patarapanich and Cheong, 1989) at different lengths and submergence depths of a horizontal plate are presented with a good agreement. It is found that the transfer of energy from the incident fundamental waves to higher harmonics becomes larger as the submergence depth ratio decreases and the length ratio increases.

• The Journal of Engineering Geology
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• v.24 no.4
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• pp.597-608
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• 2014

It is widely assumed that climate change and other anthropogenically driven processes are having a serious impact on coastal environments. One such impact is saltwater intrusion into coastal aquifers, which has resulted in the loss of groundwater resources. The pattern of saltwater intrusion is strongly dependent on regional hydrogeological characteristics. This study reviews recent qualitative and quantitative research into this problem, and considers relevant case studies. In addition, the characteristics of the aquifers from two representative volcanic islands (Jeju Island, Korea and Oahu Island, USA) are compared. The fundamental theory of density-dependent flow used to model saltwater intrusion processes and the programs that are widely used to simulate saltwater intrusion based on density-driven problems are also investigated. It is expected that the knowledge gained from this review of previous studies can be used to help improve groundwater management practices in Korea and also to inform future interdisciplinary studies.

• Journal of Korean Society on Water Environment
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• v.33 no.3
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• pp.326-333
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• 2017

The lakes and reservoirs have been reported as important sources of carbon emissions to the atmosphere in many countries. Although field experiments and theoretical investigations based on the fundamental gas exchange theory have proposed the quantitative amounts of Net Atmospheric Flux (NAF) in various climate regions, there are still large uncertainties at the global scale estimation. Mechanistic models can be used for understanding and estimating the temporal and spatial variations of the NAFs considering complicated hydrodynamic and biogeochemical processes in a reservoir, but these models require extensive and expensive datasets and model parameters. On the other hand, data driven machine learning (ML) algorithms are likely to be alternative tools to estimate the NAFs in responding to independent environmental variables. The objective of this study was to develop random forest (RF) and multi-layer artificial neural network (ANN) models for the estimation of the daily $CO_2$ NAFs in Daecheong Reservoir located in Geum River of Korea, and compare the models performance against the multiple linear regression (MLR) model that proposed in the previous study (Chung et al., 2016). As a result, the RF and ANN models showed much enhanced performance in the estimation of the high NAF values, while MLR model significantly under estimated them. Across validation with 10-fold random samplings was applied to evaluate the performance of three models, and indicated that the ANN model is best, and followed by RF and MLR models.

• Journal for History of Mathematics
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• v.19 no.4
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• pp.63-80
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• 2006

Along with natural and algebraic languages, schema is a fundamental component of mathematical language. The principal purpose of this present study is to focus on this point in detail. Schema was already in use during Pythagoras' lifetime for making geometrical inferences. It was no different in the case of Oriental mathematics, where traces have been found from time to time in ancient Chinese documents. In schma an idea is transformed into something conceptual through the use of perceptive images. It's heuristic value lies in that it facilitates problem solution by appealing directly to intuition. Furthermore, introducing schema is very effective from an educational point of view. However we should keep in mind that proof is not replaceable by it. In this study, various schemata will be presented from a diachronic point of view, We will show with emaples from the theory of categories, Feynman's diagram, and argand's plane, that schema is an indispensable tool for constructing new knowledge.

• Journal of the Korean Society for Library and Information Science
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• v.10
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• pp.71-120
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• 1983

In this study, a model curriculum for the Library and Information Science programs in Junior Colleges is presented by comparing those curricula of the Republic of Korea, the United States of America, England and Japan. In Korea, 80 credits are required for graduate of Junior College and 60 credits of that total credits are for major courses. At Toshokan Danki Daikagu in Japan, 73 credits are opened for the Department of Library Science and 87 credits for the Department of Library and Information Science respectively. In the United States of America, 30 credits for major courses out of 90 total credits are opened at Lansing Community College and 24 credits for major courses out of 60-64 credits at Mesa Community College distinctively. On the basis of the various analyses, the following principles are applied in designning the model curriculum; (1) Possibly 3 credits per subject are assigned, (2) Major credits for graduate are 60-64 credits including possible optional subjects, (3) 20 percents of those 60-64 credits shall be applied for electives, so that 72-78 credits are assigned for major, (4) In order to combine theory and practice, and to select practice areas as required major, the ratio between required and elective must be adjusted, (5) In order to avoid duplication of subject, adequate individuality must be provided, (6) The Information Science areas must be dealt with in Library Science since computer systems are being rapidly adopted in libraries and the education for resources of materials and foreign languages are also important for successful fulfillment of mediator's roles between materials and users. Therefore the following model curriculum is suggested; 31 credits in 11 subjects for required major, 46 credits in 18 subjects for electives in major, total 77 credits for 29 subjects are established, and it includes such areas as material organization, foreign languages, resources of materials, library management, information science, fundamental studies, services and practice.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.5
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• pp.1105-1111
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• 2005

In order to investigate the meanings and bases of transforming theories of diseases(病傳論), several relevant theories were collected from medical books since . The outside-to-inside changing process(pyoree jeon) was the fundamental pattern in febrile diseases regardless of slang han and wen bing after Han dynasty. But in case of numb disease the three exogenous pathogenic factors of wind, cold and dampness got into each viscera through five tissues like skin, vessesl, flesh, tendons, bones respectively. It was called corresponding changing process(sanghap jeon) here. The pathogenic changing process(byungsa jeon) had complicated details to explain pathologic processes, but could give useful informations on evaluating relative strength of pathogens and tendency ahead. The changing process of diseases of internal injuries were explained in case of emotional distress which is outbroken abruptly didn't follow regular order of viscera-emotion relations. So it was named random changing process(bulcha jeon) after 's usage. And marasmus and asthenic disease followed top-to-down or down-to-top changing process(sangha jeon) based on . There are many types of changing process of diseases between viscera and viscera or viscera and bowels like generation changing process, restriction changing process, changing process between couple, changing process of mutual transmission based on attributions of each element by the theory of 5 phases(五行論). And changing process to a neighbor doesn't have any special relations within two organs but has anatomical contiguity and physiological continuity between them. The transforming theories of diseases bring forth useful understanding on comings and goings of pathogenic factors and tendency and prognosis of disease, so they are needed to be taught in the course of pathology class.

• Journal of Korean Physical Therapy Science
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• v.17 no.3_4
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• pp.41-49
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• 2010

Purpose: The purpose of this study was to investigate purpose of education, goal and curriculums of physical therapy department. Methods: It was carried out a questionnaire survey with total 74 colleges that have the department of physical therapy including the 3-year course (36 colleges) and 4-year course (38 college) from June 10 to August 7, 2010 and collected the data from total 64 colleges including 35 colleges with 4-year course and 29 colleges with 3-year course. Results: First, the purposed and objectives of the physical therapy education of the individual colleges were all excellent, but those of the colleges with 4-year course was a little higher than those of the colleges with 3-year course. Second, the evaluation of the curricula of the individual colleges showed that they have low degree of connection, continuation and integrity and the theory and practice were not harmonized, and scores were low especially in the practice. Third, we have classified the curricula of the individual colleges and found that the practice-based education was lacking among the curricula of Korea. Conclusion: In this study, the fundamental data for the establishment of the integrated and professional physical therapy education system was provided to improve the physical therapy education and the efficiency of the clinical work in the current, fast-moving status of physical therapy. Further study is necessary to present a more standardized curriculum.

• The Journal of Korean Academic Society of Nursing Education
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• v.8 no.1
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• pp.108-119
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• 2002

This paper as the basic study aiming the establishment of nursing theory according to Korean culture, is made to reveal the types of recognition about concepts of health immanent in Korean who have the health view, completely mixed with traditional oriental medicine and Confucianism and Buddhism and Shamanism and european scientific medicine, etc. This paper is using the Q-method, which is greatly effective in measuring the individual subjectivity, to collect rightly the concepts of health of objects. This analysis shows us the 4 types of recognition about concepts of health immanent in Korean as follows. Type Ⅰ: modern self-searching type(現代的 自己 追求型), Type Ⅱ: nature-sharing type(自然 共有型), Type Ⅲ: meaning-intentional altruism(意味 指向的 他者 中心型), Type Ⅳ: oriental adaptational type(東洋的 順應型). The men belonging to type Ⅰ have positive and self-searching view of health. They are not only interpreting the concept of health scientifically, but also positively accepting the oriental concept of health. The men belonging to type Ⅱ have strong tendency of down-to-earth. They not only have the naturalistic view of health as Taoist, but also carry the weight in the family and neighbour and regard co-sharing as excellent virtue. The men belonging to type Ⅲ are positive altruists, pursuing the meaning of life and at the same time setting the importance to the good value system. Naturally they care more the family and neighbour than themselves. The men belonging to type Ⅳ have oriental view of the world characterized by nature-adaptation. They positively agree to the Shamanism, Buddhism, Confucianism and Oriental concept of health. In conclusion, in all types we can see that Korean understand the harmony of man and nature as fundamental principle of heath and carry the more importance to the mind(心) than body(身) and at the same time esteem more the family-centric, oriental and organic community than individual. All above facts is immersed in the concepts of health of Korean as a common denominator.

• The Journal of Korean Academic Society of Nursing Education
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• v.7 no.2
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• pp.349-359
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• 2001

The purpose of this study was to find the experiences to be cared of nursing students in the teaching-learning process of nursing education and provided the fundamental data of nursing education. For this study, the analytical theory of Benner's Interpretive Phenomenology was applied and the research question was 'How do the nursing students to be cared in the teaching-learning process of nursing education?' All 64 junior and senior nursing students who volunteered for this study were interviewed. The data was collected by open-ended audiotaped interview or written descriptions of situations they had experienced with a caring faculty member. All the contents of interview were recorded while interviewing with the each participants from the April 1998 to September 2000. The conclusions, obtained from the study on experiences to be cared of nursing students, were as follows ; 1. The nursing students considered the relationship with professor as very important matter. 2. The significant and important themes to nursing student be cared in the teaching-learning process of nursing education were Concern, Support, Information and Acceptance. 3. The result of this study explained the content and stage of nursing education applying 4 themes, therefore its practical use as material of nursing education was considered. Based on this study, the practical use of this results as nursing education data and the experimental study for measuring the effect of caring in the teaching-learning process of nursing education were suggested.