• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.5
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• pp.448-454
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• 2000

This study was to examine the physicochemical characteristics of coagulation reaction between ignited oyster shell powder (IOSP) and red tide organisms (RTO), and its feasibility, in developing a technology for the removal of RTO bloom in coastal sea,IOSP was made from oyster shell and its physicochemical characteristics were examined for particle size distribution, surface characteristic by scanning electron microscope, zeta potential, and alkalinity and pH variations in sea water. Two kinds of RTO that were used in this study, Cylindrotheca closterium and Skeletonema costatum, were sampled in Masan bay and were cultured in laboratory. Coagulation experiments were conducted using various c(Incentrations of IOSP, RTO, and a jar tester. The supernatant and RTO culture solution were analyzed for pH, alkalinity, RTO cell number, IOSP showed positive zeta potentials of $11.1{\~}50.1\;mV\;at\;pH\;6.2{\~}12.7$, A positive zeta potential of IOSP slowly decreased with decreasing pNa 4,0 to 2,0. When pNa reached zero, the zeta potential approached zero, When a pMg value was decreased, the positive zeta potential of IOSP increased until pMg 3.0 and decreased below pMg 3.0. IOSP showed 4.8 mV of positive zeta potential while RTO showed -9.2 mV of negative zeta potential in sea water. A positive-negative EDL (electrical double-layer) interaction occurred between $Mg(OH)_2$ adsorption layer of IOSP and RTO in sea water so that EDL attractive force always worked between them. Hence, their coagulation reaction occurred at primary minimum on which an extreme attractive force acted because of charge neutralization by $Mg(OH)_2$ adsorption layer of IOSP. As a result, the coagulation reaction was rapidly processed and was irreversible according to DLVO (Deriaguin-Landau-Verwey-Overbeek) theory. Removal rates of RTO were exponentially increased with increasing both IOSP concentration and G-value. The removal rates were steeply increased until 50 mg/l of IOSP and reached $100{\%}\;at\;400\;mg/l$ of IOSP. Removal rates of RTO were $70.5,\;70.5,\;81.7,\;85.3{\%}$ for G-values of $1,\;6,\;29,\;139\;sec^(-1)$at IOSP 100 mg/l, respectively. This indicated that mixing (i.e., collision among particles) was very important for a coagulation reaction.

• Journal of the Korean Institute of Landscape Architecture
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• v.16 no.2
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• pp.43-57
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• 1988

The purpose of this thesis is to suggest objective basic data for park management proposal through the quantitative analysis of users' behaviors and satisfaction for the actual conditions of management in the Chiri Mountain National Park. For this users' behaviors and socio-economic characteristics have been cross-analyzed. Specifically, it attempts to investigate users' anticipate and degree of satisfaction applied Expectancy Theory by Likert attitude scale. Users'behaviors patterns of each site have been analyzed by the factor analysis algorithm, and each factor scores of sites have been clustered by the cluster method. And also user' satisfaction for the actual conditions of management have been analyzed by using the multiple regression. The major user groups were students and youth groups accompanied by their friends ranging from 3 to 10. The values of user'post occupancy-evaluation for such as rockwall climbing and praying on the mountain of each site showed higher than those of anticipated, but evaluation values of other activities were lower. The user'behaviors of each site have been analyzed five factors by factor analysis algorithm. By using the control method for the number of factors, T.V. has been obtained as 50.58%. The factor score of factor covering the behavior patterns of student and youth yield high EV. and C.V.. On the analysis of cluster using factor score, factor IV in Hwaomsa temple site and Ssanggyesa temple site, factor II, v in Jungsanri Valley site, factor, I, III in Bangmudong valley site and factor I. IV in Baemsagol vallry site showed very high values, respectively. According to the multiple regression analysis, the major variables related to the satisfaction for the actual conditions of vegetation and landscape managements were reservation of groundcover, recovery of artificial injury, the surroundings of camping and temple site. In the park facilities and operation, the major variables related to the satisfaction were conditions of management such amenity facilities as privy, sign board, junk yard, camping site, and guidance of excursion, campaign and preservation of nature.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.1 no.1
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• pp.33-42
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• 1981

Current standard code for R.C. design consists of two conventional design parts, so called WSD and USD, which are based on ACI 318-63 and 318-71 code provisions. The safety factors of our WSD and USD design criteria which are taken primarily from ACI 318-63 code are considered to be not appropriate compared to out country's design and construction practices. Furthermore, even the ACI safety factors are not determined from probabilistic study but merely from experiences and practices. This study investigates the safety level of R.C. flexural members designed by the current WSD safety provisions based on Second Moment Reliability theory, and proposes a rational but efficient way of determining the nominal safety factors and the associated flexural allowable stresses of steel bars and concretes in order to provide a consistent level of target reliability. Cornell's Mean First-Order Second Moment Method formulae by a log normal transformation of resistance and load output variables are adopted as the reliability analysis method for this study. The compressive allowable stress formulae are derived by a unique approach in which the balanced steel ratios of the resulting design are chosen to be the corresponding under-reinforced sections designed by strength design method with an optimum reinforcing ratio. The target reliability index for the safety provisions are considered to be ${\beta}=4$ that is well suited for our level of construction and design practices. From a series of numerical applications to investigate the safety and reliability of R.C. flexural members designed by current WSD code, it has been found that the design based on WSD provision results in uneconomical design because of unusual and inconsistent reliability. A rational set of reliability based safety factors and allowable stress of steel bars and concrete for flexural members is proposed by providing the appropriate target reliability ${\beta}=4$.

• The Journal of Art Theory & Practice
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• no.2
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• pp.49-74
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• 2004

It has been frequently pointed out that the established art history with the stylistic and iconographic interpretations and monographic analysis is fallen behind the currency of modern art. Among those who claimed the crisis in the discipline of art history, there is a suggestion that the art historical study should be fostered by other factors in the fields of the humanities. The so called New Art History or 'visual Culture Studies' insists that art history has to be restructured to integrate the broader study of culture and society, and by now, such an opinion is not a novelty at all. One of the most significant yet overlooked elements that induced the new currency of art history is properties of contemporary art that conflict the traditional claim of art historians. Although the idea that art is not purely aesthetic but that it has many other functions has been brought up by the art historians, it was the artists that provoked such a perception. When Arthur C. Danto and Hans Belting proclaimed the End of Art and Art History in the 1980s, the concept of art has been changed radically through the avant-garde tendency of Modernism and a new pluralism of Postmodernism. One dominant concern that strikes art historians is to find a new approach to art, since the traditional method and goal of analysis for past art and past art history seem unavailable. The perplexity arising from the situation is intensified in the field of teaching art, especially for those who teach art history in art school. Basically art history is a pursuit of learning of art in history, and its purpose is to reconcile the present with the past and the future as well. Since Modernism, as it is confusing sometimes because it implies the present state, somehow art became considered 'tradition-less'. It does not mean that a work of art stands aloof from the past attainments, hut modern art imposed itself on a task seeking after the new for its own sake, turning its back on the tradition. And now in the era of Postmodernism, an historians face the requirement to revaluate the whole history of art including modernism. The necessity of art history in art education is indisputable, but methods and contents in the academic courses should he reexamined now. Because artists' concept of history and past art has been altered, and art history as a humanistic discipline can only maintain its identity through incorporation with art itself. Academics teaching art history, or, strictly speaking, past works of art and history, to the student in art school, confront with the need to rethink the object of art history and its meaning to the artists.

• Journal of the Korean Society of School Health
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• v.11 no.1
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• pp.63-74
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• 1998

The purposes of this study are to show in interpersonal relations what factors male students are stressed from, how they experience stress, how they cope With it in each situation, and what this results in It attempt to gam basic materials to promote male student health and positive coping methods, The subject of this study was 15 male students of C University located in Seoul and Kyeonggui-Do They were composed of 5 sophomores, 5 Juniors and 5 seniors The period for collecting materials was October 1997 to January 1998, and the interview time ranged from 50 minutes to two hours The interview frequency was one to three times as occasion demanded, The materials were analyzed by the methods and theory suggested by Strauss & Corbin (1990) The results were 130 categories grouped into 33 divisions by similarity Finally, they were united into 9 higher categories In interpersonal relations the core category of male student stress is "affliction", and it follows the course of generation-coping-resolution The types showed in the course of material analysis are as follows, (1) When the subject student is on good terms with the other and the stress is repeated- "affliction" is strong and continuous-and his ability sense is strong, he copes with "affliction" With his own will and solves It affirmatively, (2) When the subject student is on good terms with the other and the stress is repeated-so "affliction" is strong and continuous-and his ability sense is weak, he copes with "affliction" with an emotional bias and solves it negatively (3) When the subject student is on good terms with the other and the stress is temporary-"affliction" is strong and temporary-and his ability sense is strong, he copes with "affliction" with his own will and solves it affirmatively (4) When the subject student becomes estranged from the other and the stress is temporary-"affliction" is weak and temporary-and his ability sense is weak, he copes with "affliction" with an emotional bias and solves it negatively, (5) When the subject student becomes estranged from the other and the stress is repeated-"affliction" is strong-and continuous and his ability sense is strong, he copes with "affliction" with his own will and solves it affirmatively (6) When the subject student becomes estranged from the other and the stress is repeated-"affliction" is strong and continuous-and his ability sense is weak, he copes with "affliction" with an emotional bias and solves it negatively. According to the above results, the conditions of cause and effect for male students to generate "affliction" should be understood in order to help cope with stress caused by interpersonal relations A program for education and counseling should be developed for male students to strengthen their 'ability sense' in choosing coping strategies In addition, the individual estimation for ability sense should be performed when education and counseling them.

• Journal of architectural history
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• v.5 no.2 s.10
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• pp.25-39
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• 1996

Architectural researches on the traditional houses of Korea have been studied mainly based on the data collected in the field survey. From explosively incresed real mesurements and drawings in the field, plenty of data have been collected. Those have been the basic data for verifing and developing the theories on the traditional house. But after Korean war the researchers in South-Korea were not able to approach to the field in North Korea, so the new data of North Korea were not added any more. The poverty of real data have caused regional unbalance in the researches. This paper aims at collecting new data of traditional house in North Korea. But still being prohibited for the researchers of South Korea to approach to the field, I had to depend on the memories and experiences of the immigrants from North Korea who are now living in Kyon-Nam and Pusan Province. Through the questionnaire and drawings, they described vivid memory of their old houses. I was able to collect the data of 71 cases, which are significant and valuable as much as those of the real field are. The data include the address and site condition, family structure, economic condition, construction period of each house, The drawings by themselves show the building forms and plans, the plans of each building, and the included spaces. Although the quantity of those data is not enough for statistical analysis, it shows general tendency for analizing regional charateristics, the differnces among economical classes, and the periodical change. It opens the way for verfying the existing theory. Analizing the data, I have some conclusions as followings: a. Most of researchers have classified the dominant housing type of Hamkyong-Do as 'the double fold' type. In this study, all cases of Hamkyongbuk-do also show 'the double fold plan with Chongju-kan'. But in Hamkyongnam-do some cases show 'the double fold plan without Chongju-kan, or projecting the stable into the yard, which seem to be different type from 'the double fold plan with Chongju-kan' b. Existing theories classified the dominant housing type of Pyongahn-do as 'two buildings with pararell arrangement'. This classification is verified with the plentiful cases in this study. Futhermore, I found new tendency, that is, getting higher econnomic condition, they construct annex buildings between the main buildings. Finally their houses show 'scattered ㅁ shape'. The houses included in this two types has narrow and closed inner yard, which is different from the houses of the same shape in the south region of Korea. c. Existing theories classified the dominant housing type of Hwanghae-do as 'ㅁ sape with Daechong' type. I found many cases of 'ㅁ shape', but only two cases show 'Daechong'. 'The doble fold' type was also founded. Unfortunately very few cases were sent from Hwanghae-do, it is not enough for finding general tendency.

• Education of Primary School Mathematics
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• v.4 no.2
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• pp.111-125
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• 2000

This paper presents cross-national perspectives on challenges in implementing current mathematics education reform ideals. This paper includes detailed qualitative descriptions of mathematics instruction from unevenly successful second-grade classrooms both in Koran and in the U. S with regared to reform recommendations. Despits dramatic differences in mathematics achivement between Korean and the U.S student. problems in both countries with regard to mathematics education are perceived to be very similar. The shared problems have a common origin in teacher-centered instruction. Educational leaders in both countries have persistently attempted to change the teacher-centered pedagogy to a student-centered approach. Many teachers report familiarity with and adherence to reform ideas, but their actual classroom teaching practices do not reflect the full implications of the reform ideals. Given the challenges in implementing reform, this study explored the breakdown that may occur between teachers adoption of reform objectives and their successful incorporation of reform ideals by comparing and contrasting two reform-oriented classrooms in both countries. This comparison and contrast provided a unique opportunity to reflect on possible subtle but crucial issues with regard to reform implementation. Thus, this study departed from past international comparisons in which the common objective has been to compare general social norma of typical mathematics classes across countries. This study was and exploratory, qualitative, comparative case study using grounded theory methodology based on constant comparative analysis for which the primary data sources were classroom video recordings and transcripts. The Korean portion of this study was conducted by the team of four researchers, including the author. The U.S portion of this study and a brief joint analysis were conducted by the author. This study compared and contrasted the classroom general social norms and sociomathematical norms of two Korean and two U.S second-grade teachers who aspired to implement reform. The two classrooms in each country were chosen because of their unequal success in activating the reform recommendation. Four mathematics lessons were videotaped from Korean classes, whereas fourteen lessons were videotaped from the U.S. classes. Intensive interviews were conducted with each teacher. The two classes within each country established similar participation patterns but very different sociomathematical norms. In both classes open-ended questioning, collaborative group work, and students own problem solving constituted the primary modes of classroom participation. However in one class mathematical significance was constituted as using standard algorithm with accuracy, whereas the other established a focus on providing reasonable and convincing arguments. Given these different mathematical foci, the students in the latter class had more opportunities to develop conceptual understanding than their counterparts. The similarities and differences to between the two teaching practices within each country clearly show that students learning opportunities do not arise social norms of a classroom community. Instead, they are closely related to its sociomathematical norms. Thus this study suggests that reform efforts highlight the importance of sociomathematical norms that established in the classroom microculture. This study also provides a more caution for the Korean reform movement than for its U.S. counterpart.

• KDI Journal of Economic Policy
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• v.34 no.2
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• pp.1-15
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• 2012

We develop an identity choice model within the context of a stereotyping-cum-signaling framework. The model allows us to explore implications of the fact that, when individuals can choose identity, then the distribution of abilities within distinct identity groups becomes endogenous. This is significant because, when identity is exogenous and if the ability distributions within groups are the same, then inequality of group reputations in equilibrium can only arise if there is a positive feedback between group reputation and individual human capital investment activities (Arrow, 1973; Coate and Loury, 1993). Here we show that when group membership is endogenous then the logic of individuals' identity choices leads there to be a positive selection of higher ability individuals into the group with a better reputation. This happens because those for whom human-capital-investment is less costly are also those who stand to gain more from joining the favored group. As a result, ability distributions within distinct groups can endogenously diverge, reinforcing incentive-feedbacks. We develop the theoretical framework that can examine the positive selection and the endogenous group formation. The model implies that inequality deriving from stereotyping of endogenously constructed social groups is at least as great as the inequality that can emerge between exogenously given groups.

• Membrane Journal
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• v.12 no.2
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• pp.97-106
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• 2002

Small angle light scattering (SALS) and field emission scanning electron microscope (FE-SEM) have been used to investigate the light scattering patterns with time evolved during water vapor quenching (relative humidity of 53 (${\pm}3)%$ at $26^{\circ}C$ of polysulfone (PSf)/NMP/Alcohol and chlorinated poly(vinyl chloride) (CPVC)/THF/Alcohol, respective1y. Time dependence of the position of the light scattering maximum was observed at PSf dope solutions, confirming spinodal decomposition (SD), while CPVC dope solutions showed a decreased scattered light intensity with an increased q-value, indicating nucleation & growth (NG). For the each system, domain growth rate in the intermediate and late stage of phase separation decreased with increasing the number of carbon of alcohol used as additive (non-solvent). Also, in the early stage for SD, the scattering intensity with time was in accordance with Cahn's linear theory of spinodal decomposition, regardless of types of non-solvent additive. Also, the size scales obtained by SALS were mutually compared to domain sizes gained by FE-SEM measurement. These observations of scattering pattern were much clearly observed for the 20PSf/70NMP/10n-butanol (w/w%) and agreed with the theoretical predictions for scattering patterns of each stage like the early, the intermediate, and the late stage of SD type phase separation. As the scattering maximum was observed at the larger angles (larger q) in the order of n-butanol > n-propanol > methanol > no alcohol, the pore size of final morphology decreased.

• Journal of Acupuncture Research
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• v.18 no.5
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• pp.77-91
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• 2001

Backgrounds and purpose : The acupuncture of oriental medicine is very important in treatments. Until now it was been researched according to the meridian and qi xue(氣血) phenomenon of oriental medicine's theory. Acupuncture will show more objective index to observe the meridian. And then, I studied the effects on the thermal change of the Taeyon($L_9$) and Chungbu($L_1$) following acupuncture stimulation. Objective and Methods : This study was performed from December 1999 to February 2000 on 60 healthy students. The objective was divided into two groups, those are the control group A(N=30) that no acupuncture stimulation, the group B(N=30) of acupuncture stimulation on Taeyon($L_9$). First, in the control group A, I took a picture Taeyon($L_9$) Chungbu($L_1$) Taenung($P_7$) Chondol($CV_{22}$) area for 30 men without any stimulation with the Digital Infrared Thermograph Imaging(D.I.T.l.) and did same area, 10min after. Second, in the acupuncture stimulation group B, we took a picture Taeyon($L_9$) Chungbu($L_1$) Taenung($P_7$) Chondol($CV_{22}$) area for 30 men without any stimulation with the Digital Infrared Th - ermograph Imaging(D.I.T.I.), and then stimulate acupuncture on Taeyon($L_9$) and took a picture same area, 10min after. Results : 1. In healthy men, average skin temperture on Taeyon($L_9$) area was lower than Chungbu($L_1$) area about $3.0^{\circ}C$, in the Lt. Taeyon($L_9$) and Chungbu($L_1$) area was lower than Rt. Taeyon($L_9$) and Chungbu($L_1$) area. 2. In the acupuncture stimulation group B, the skin temperature of both side Taeyon($L_9$) area showed the increase or decrease significantly. But both Taenung($P_7$) area did not showed significantly. 3. In the acupuncture stimulation group B, the skin temperature of both side Chungbu($L_1$) area showed the increase or decrease significantly. But both Chondol($CV_{22}$) area did not showed significantly. 4. The thermal changes of the area which is a meridian point in the Lung Meridian of the acupuncture stimulation group on Taeyon($L_9$) different from other Meridian with significantly change. Conclusion : The acupuncture stimulation on Taeyon($L_9$) affected the thermal change of the area which is a meridian point, in the Lung Meridian. And then I could relate these results with the existence of the meridian and meridian point. Thus, continuous thermographic study will be needed for the existence of the meridian and meridian point.