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A Study on Curriculum Improvement of the Korea Army Nursing Academy (국군간호사관학교 교육과정 개선을 위한 기초 연구)

  • 고자경
    • Journal of Korean Academy of Nursing
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    • v.13 no.2
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    • pp.22-43
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    • 1983
  • 1. Need for and Purpose of the Study. There is an increasing demand for curriculum improvement of the Korean Army Nursing Academy (KANA), since it was upgraded into 4-year institution of higher learning from 3-year one. In particular, it is strongly advocated that the KANA needs the outside expertise for its curriculum improvement-namely not only from the internal military view of points but also from the viewpoints of professional educational society, In line with such a necessity for the study, this study was aimed at 1) analyzing the current actual practices of KANA'S curriculum, 2) investigating the desired practices of KANA'S curriculum, and 3) identifying the discrepancy between the actual and desired practices of curriculum. 2. Problems for the Study This study had 4 problems to be answeared as follows: 1) What are the actual curriculum practices of KANA? 2) What are the desired curriculum practices of KANA? 3) How are the extents of perception of actual and desired curriculum different in four groups (student, faculty & administrator, nurse, and medical doctor in militay hospital) ? 4) What are the restraining forces that impede the change from actual to desired curriculum practices? 5) What are the relationships of curriculum component,』 in actual and desired curriculum practices? 3. Methods and Procedures This study was conducted by means of document analysis in addition to literature review and by means of needs assessment questionnaire which was developed by the researcher. The questionnaire included 62 statments with 7 questions for demographic data collection. The needs assessment questionnaire was managed to a total of 243 subjects (100 students, 46 faculty & administrators, 55 nurses, and 42 medical doctors), The collected data were treated using SPSS computer system so as to calculate mean scores, standard deviations, and correlation coefficients. The significance test was made through t-test and one-way ANOVA. The statistical significance level was set at both .05 and .01 level. 4. Major findings The major findings in this study are as follows: 1) The score of desired practices was significantly greater than that of actual practices, representing a strong need for curriculum betterment. 2) There were significant differences in the perceptions of actual practices as well as desired practices among four groups (student, faculty & administrater, nurse, and medical doctor). 3) The most frequently selected restraining forces were army's inherent character, economical limitation, and educational expertise limitations. 4) Such variables as sex, position attachment to the KANA and grade made a statistically significant effect on the perception of desired curriculum practice, while the variables like marrige, position, and military class made it on the perception of actual curriculum practice. 5) The coefficients among the curriculum components were lower in perception of the actual curriculum practices than those in the desired practices. 5. Conclusions The conclusions based on the major findings of this study are as follows: 1) The current curriculum development procedure of the KANA is not consistent with the theoretical frame of systematic development sarategy of curriculum. 2) There are wide conflicts among the groups who are supposed to participate in curriculnm development, concerning the actual and desired practices of KANN'S curriculum. 3) A great deal of need for curriculum improvement for the KANA is clearly felt, and in particular, in the process of teaching and learning. 4) Each component of curriculum is not intergrated into a whole development procedure, being segregated each other. 5) For better curriculum improvement, such restraining forces as financial and professional limitations should be eliminated. 6. Recommendations 1) For Further Research a. There is a need to replicate this study after in-depth statistical analysis of each item of need assessment questionnaire, and with more representative subjects. b. A study should be conducted which. has its focus on the analysis of restraining forces for the change from actual to desired curriculum practices of the KANA. 2) For KANA'S Curriculum Improvement a. There is a need to promote the professional expertise of the participants in curriculum development and the communication among them. b. It is desirable to establish an institution or section of administration, which is soley in charge of curriculum development. c. To better develop KANA's curriculum not only faculty and administrators but also students should be encouraged to participate in development process, while the military medical doctors' participation should be carefully considered.

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Investigating the Cognitive Process of a Student's Modeling on a Modeling-Emphasized Argument-Based General Chemistry Experiment (모델링을 강조한 논의 기반 일반화학실험에서 학생들의 모델링에 대한 인지과정 탐색)

  • Lee, Dongwon;Cho, Hey Sook;Nam, Jeonghee
    • Journal of The Korean Association For Science Education
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    • v.35 no.2
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    • pp.313-323
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    • 2015
  • The purpose of this study is to investigate the cognitive process of student's modeling on a modeling-emphasized argument-based general chemistry experiment. The participants were twenty-one freshman students. Six topics were carried out during the first semester and semi-structured interview was implemented at the end of the semester. Semi-structured interview questions were used to elicit elements of effective model, modeling strategies, difficulties that students have experienced during modeling, and resolving the difficulties that students have experienced during modeling. All student interview data were collected and transcribed. The results of this study are summarized as follows: (1) Elements of effective model were considered to be visual expression, persuasive explanation, and rhetorical structure. (2) Modeling strategies included arranging important keywords or writing the outline, and during the modeling process, students used various data, suggested data after reconstructing, suggested definitions and explanations of core concepts, used meta-cognition, and considering rhetorical structure. (3) Difficulties students have experienced during modeling could be categorized as lack of modeling strategy and understanding. (4) Resolving difficulties students have experienced during modeling could be categorized as modeling strategy and understanding. Students learn the strategy by feedback, modeling experience, evaluation of experimental report, models which they constructed previously and references, and the understanding of contents were achieved through arguments which occurred during classes and during the process of writing the experimental reports. These results suggest that when using modeling in teaching and learning, the argument-based learning strategy can be effective in enhancing students' modeling by helping them to understand meta-modeling with scientific concepts.

The development of Home Economics Education program for the prevention of school violence in middle school : Based on the Practical Action Teaching Model (학교폭력 예방을 위한 중학교 가정과 교육 프로그램 개발 - 실천적 행동 수업 모형을 적용하여 -)

  • Son, Joo Young;Chae, Jung-Hyun
    • Journal of Korean Home Economics Education Association
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    • v.25 no.2
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    • pp.103-128
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    • 2013
  • The purpose of this study was to develop a school violence prevention program featuring the Practical Action Teaching Model(hereafter, PATM) for middle school students to prevent school violence by Home Economics Education. To accomplish this purpose, the processes of analysis, design, development, and evaluation based on ADDIE were conducted. The validity of the program was evaluated twice by Home Economics education experts(36 experts for the first group and 10 experts for the second group) and the contents of the program were modified according to the comments from the evaluators. The school violence prevention program in Home Economics classes consisted of 5 topics such as changing perception on school violence, enhancing self-esteem, relating with others, practicing consideration and sharing, and strengthening the will of preventing school violence. Twenty-four units were developed with 7 practical problems(What should I do to make friends to help with each other?, What should I do to establish positive self-concept?, What should I do to communicate to build good relationship?, What should I do to solve the conflicts peacefully?, What should I do to practice consideration and sharing in food consumption?, and What should I do to practice consideration and sharing in clothing?) in 5 topic areas. Teaching-learning plans included four steps such as problem perception, practical reasoning, action, and evaluation that comprise PATM to solve the practical problems. Every step of the teaching-learning plan consisted of questions for practical reasoning and activity assignments. Materials for students and teachers were developed. Materials for students comprised 80 pieces in total including student activity, reading, movie, and clips to make students enhance understanding and interest. Materials for teachers comprised 35 pieces in total such as rationales, newspaper articles, and movies that make teachers that lesson teaching loads and were helpful for teachers. The PATM was incorporated into developing the program and a Likert-scale was used to assess usefulness, applicability, appropriateness, fidelity, substantiality, and validity of this program. This program gained more than 4.00 on a 1-5 Likert scale. This result indicated that program is expected to be effective and useful to school violence prevention.

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The Effect of Instruction for 'Family Life Planning' based on Backward Design on Learners' Understanding and Satisfaction (백워드 수업설계를 적용한 '가족생활 설계' 영역 수업이 학습자의 이해도 및 수업만족도에 미치는 효과)

  • Yoo, Se Jong;Lee, Yon Suk
    • Journal of Korean Home Economics Education Association
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    • v.30 no.3
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    • pp.43-66
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    • 2018
  • The purpose of this study was to conduct the instruction for 'Family Life Planning' based on backward design and measured the learners' understanding and satisfaction for testing validity. In short, the result of this study are as follows: In this study, first of all, the students could explain significant concepts, knowledge, and principles for the planning of family life; they could interpret and apply them; they have perspectives on them; they could empathize them; and they could have self-knowledge. The students could also accomplish high achievements for important concepts related to the field of family life planning. In conclusion, this study showed that the developed instruction was very effective for the students to achieve fruitful results, accelerating the learners' persistent understanding. Second, the learners had high satisfaction on the instruction of Family Life Planning based on backward design with the average score of 3.68 out of the perfect score 4. The students could be satisfied with the developed instruction since they could have high interest in the class thanks to diverse learning materials, and they could take an active part in the learning tasks based on group activities and questions. Also they could apply the contents that they learned through task performances to new situation and context. Therefore, this study proved that the developed instruction enhanced the learners' satisfaction on class.

A Study on the Perception of Communication Ability of University Students - A junior college of engineering students (대학생 의사소통능력 관련 인식 조사 연구 - A전문대학 공대생을 중심으로)

  • Son, Kyong Hye;Park, Young Mi
    • Journal of the International Relations & Interdisciplinary Education
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    • v.2 no.1
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    • pp.57-82
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    • 2022
  • This study aims to investigate and analyze the perception of communication capability which is one of the sub-competencies of NCS vocational substructure basic competence, and then seek the direction of prospective courses. To do this, the researcher conducts a non-face-to-face survey by creating five questions under the following five categories: The importance and necessity of communicative competence, students and educators of communicative competence classes, contents and methods of curriculum and teaching and learning, communicative competence and writing skills and operation of extracurricular programs. This researcher has been teaching basic education even before the communication skills curriculum was created in college, now, in a situation where communication skills have become selective education, it is intended to grasp the perception of college students about communication skills for first graders. This study attempted to analyze the survey area in more depth through group FGI after conducting an online survey by dividing it into several items. As a result, students felt that communication skills became motktkre important through COVID-19. Among the bottom five communication skills, speaking skills were found to be the most important, reading ability was recognized as the least important. On the other hand, there was a strong hope to know about the level of communication ability, type of communication, and method of communication about oneself. In addition, they recognized that communication skills should be learned in their first year of college, and hoped to be operated at all times as a non-disciplinary program. In particular, in the bottom five areas of communication skills, the expectations and actual hopes for speaking skills were the highest compared to the rest, and in terms of teaching and learning methods, they wanted to improve their skills through feedback and practice rather than theory. These research results have great implications for setting the direction of operation of classes, such as the content and method of classes in communication skills, in the future.

Spatial effect on the diffusion of discount stores (대형할인점 확산에 대한 공간적 영향)

  • Joo, Young-Jin;Kim, Mi-Ae
    • Journal of Distribution Research
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    • v.15 no.4
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    • pp.61-85
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    • 2010
  • Introduction: Diffusion is process by which an innovation is communicated through certain channel overtime among the members of a social system(Rogers 1983). Bass(1969) suggested the Bass model describing diffusion process. The Bass model assumes potential adopters of innovation are influenced by mass-media and word-of-mouth from communication with previous adopters. Various expansions of the Bass model have been conducted. Some of them proposed a third factor affecting diffusion. Others proposed multinational diffusion model and it stressed interactive effect on diffusion among several countries. We add a spatial factor in the Bass model as a third communication factor. Because of situation where we can not control the interaction between markets, we need to consider that diffusion within certain market can be influenced by diffusion in contiguous market. The process that certain type of retail extends is a result that particular market can be described by the retail life cycle. Diffusion of retail has pattern following three phases of spatial diffusion: adoption of innovation happens in near the diffusion center first, spreads to the vicinity of the diffusing center and then adoption of innovation is completed in peripheral areas in saturation stage. So we expect spatial effect to be important to describe diffusion of domestic discount store. We define a spatial diffusion model using multinational diffusion model and apply it to the diffusion of discount store. Modeling: In this paper, we define a spatial diffusion model and apply it to the diffusion of discount store. To define a spatial diffusion model, we expand learning model(Kumar and Krishnan 2002) and separate diffusion process in diffusion center(market A) from diffusion process in the vicinity of the diffusing center(market B). The proposed spatial diffusion model is shown in equation (1a) and (1b). Equation (1a) is the diffusion process in diffusion center and equation (1b) is one in the vicinity of the diffusing center. $$\array{{S_{i,t}=(p_i+q_i{\frac{Y_{i,t-1}}{m_i}})(m_i-Y_{i,t-1})\;i{\in}\{1,{\cdots},I\}\;(1a)}\\{S_{j,t}=(p_j+q_j{\frac{Y_{j,t-1}}{m_i}}+{\sum\limits_{i=1}^I}{\gamma}_{ij}{\frac{Y_{i,t-1}}{m_i}})(m_j-Y_{j,t-1})\;i{\in}\{1,{\cdots},I\},\;j{\in}\{I+1,{\cdots},I+J\}\;(1b)}}$$ We rise two research questions. (1) The proposed spatial diffusion model is more effective than the Bass model to describe the diffusion of discount stores. (2) The more similar retail environment of diffusing center with that of the vicinity of the contiguous market is, the larger spatial effect of diffusing center on diffusion of the vicinity of the contiguous market is. To examine above two questions, we adopt the Bass model to estimate diffusion of discount store first. Next spatial diffusion model where spatial factor is added to the Bass model is used to estimate it. Finally by comparing Bass model with spatial diffusion model, we try to find out which model describes diffusion of discount store better. In addition, we investigate the relationship between similarity of retail environment(conceptual distance) and spatial factor impact with correlation analysis. Result and Implication: We suggest spatial diffusion model to describe diffusion of discount stores. To examine the proposed spatial diffusion model, 347 domestic discount stores are used and we divide nation into 5 districts, Seoul-Gyeongin(SG), Busan-Gyeongnam(BG), Daegu-Gyeongbuk(DG), Gwan- gju-Jeonla(GJ), Daejeon-Chungcheong(DC), and the result is shown

    . In a result of the Bass model(I), the estimates of innovation coefficient(p) and imitation coefficient(q) are 0.017 and 0.323 respectively. While the estimate of market potential is 384. A result of the Bass model(II) for each district shows the estimates of innovation coefficient(p) in SG is 0.019 and the lowest among 5 areas. This is because SG is the diffusion center. The estimates of imitation coefficient(q) in BG is 0.353 and the highest. The imitation coefficient in the vicinity of the diffusing center such as BG is higher than that in the diffusing center because much information flows through various paths more as diffusion is progressing. A result of the Bass model(II) shows the estimates of innovation coefficient(p) in SG is 0.019 and the lowest among 5 areas. This is because SG is the diffusion center. The estimates of imitation coefficient(q) in BG is 0.353 and the highest. The imitation coefficient in the vicinity of the diffusing center such as BG is higher than that in the diffusing center because much information flows through various paths more as diffusion is progressing. In a result of spatial diffusion model(IV), we can notice the changes between coefficients of the bass model and those of the spatial diffusion model. Except for GJ, the estimates of innovation and imitation coefficients in Model IV are lower than those in Model II. The changes of innovation and imitation coefficients are reflected to spatial coefficient(${\gamma}$). From spatial coefficient(${\gamma}$) we can infer that when the diffusion in the vicinity of the diffusing center occurs, the diffusion is influenced by one in the diffusing center. The difference between the Bass model(II) and the spatial diffusion model(IV) is statistically significant with the ${\chi}^2$-distributed likelihood ratio statistic is 16.598(p=0.0023). Which implies that the spatial diffusion model is more effective than the Bass model to describe diffusion of discount stores. So the research question (1) is supported. In addition, we found that there are statistically significant relationship between similarity of retail environment and spatial effect by using correlation analysis. So the research question (2) is also supported.

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  • Study of Patient Teaching in The Clinical Area (간호원의 환자교육 활동에 관한 연구)

    • 강규숙
      • Journal of Korean Academy of Nursing
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      • v.2 no.1
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      • pp.3-33
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      • 1971
    • Nursing of today has as one of its objectives the solving of problems related to human needs arising from the demands of a rapidly changing society. This nursing objective, I believe, can he attained by the appropriate application of scientific principles in the giving of comprehensive nursing care. Comprehensive nursing care may be defined as nursing care which meets all of the patient's needs. the needs of patients are said to fall into five broad categories: physical needs, psychological needs, environmental needs, socio-economic needs, and teaching needs. Most people who become ill have adjustment problems related to their new situation. Because patient teaching is one of the most important functions of professional nursing, the success of this teaching may be used as a gauge for evaluating comprehensive nursing care. This represents a challenge foe the future. A questionnaire consisting of 67 items was distributed to 200 professional nurses working ill direct patient care at Yonsei University Medical Center in Seoul, Korea. 160 (80,0%) nurses of the total sample returned completed questionnaires 81 (50.6%) nurses were graduates of 3 fear diploma courser 79 (49.4%) nurses were graduates of 4 year collegiate nursing schools in Korea 141 (88,1%) nurses had under 5 years of clinical experience in a medical center, while 19 (11.9%) nurses had more than 5years of clinical experience. Three hypotheses were tested: 1. “Nurses had high levels of concept and knowledge toward patient teaching”-This was demonstrated by the use of a statistical method, the mean average. 2. “Nurses graduating from collegiate programs and diploma school programs of nursing show differences in concepts and knowledge toward patient teaching”-This was demonstrated by a statistical method, the mean average, although the results showed little difference between the two groups. 3. “Nurses having different amounts of clinical experience showed differences in concepts and knowledge toward patient teaching”-This was demonstrated by the use of a statistical method, the mean average. 2. “Nurses graduating from collegiate programs and diploma school programs of nursing show differences in concepts and knowledge toward patient teaching”-This was demonstrated by a statistical method, the mean average, although the results showed little difference between the two groups. 3. “Nurses having different amounts of clinical experience showed differences in concepts and knowledge toward patient teaching”-This was demonstrated by the use of the T-test. Conclusions of this study are as follow: Before attempting the explanation, of the results, the questionnaire will he explained. The questionnaire contained 67 questions divided into 9 sections. These sections were: concept, content, time, prior preparation, method, purpose, condition, evaluation, and recommendations for patient teaching. 1. The nurse's concept of patient teaching: Most of the nurses had high levels of concepts and knowledge toward patient teaching. Though nursing service was task-centered at the turn of the century, the emphasis today is put on patient-centered nursing. But we find some of the nurses (39.4%) still are task-centered. After, patient teaching, only a few of the nurses (14.4%) checked this as “normal teaching.”It seems therefore that patient teaching is often done unconsciously. Accordingly it would he desirable to have correct concepts and knowledge of teaching taught in schools of nursing. 2. Contents of patient teaching: Most nurses (97.5%) had good information about content of patient teaching. They teach their patients during admission about their diseases, tests, treatments, and before discharge give nurses instruction about simple nursing care, personal hygiene, special diets, rest and sleep, elimination etc. 3. Time of patient teaching: Teaching can be accomplished even if there is no time set aside specifically for it. -a large part of the nurse's teaching can be done while she is giving nursing care. If she believes she has to wait for time free from other activities, she may miss many teaching opportunities. But generally proper time for patient teaching is in the midmorning or midafternoon since one and a half or two hours required. Nurses meet their patients in all stages of health: often tile patient is in a condition in which learning is impossible-pain, mental confusion, debilitation, loss of sensory perception, fear and anxiety-any of these conditions may preclude the possibility of successful teaching. 4. Prior preparation for patient teaching: The teaching aids, nurses use are charts (53.1%), periodicals (23.8%), and books (7.0%) Some of the respondents (28.1%) reported that they had had good preparation for the teaching which they were doing, others (27.5%) reported adequate preparation, and others (43.8%) reported that their preparation for teaching was inadequate. If nurses have advance preparation for normal teaching and are aware of their objectives in teaching patients, they can do effective teaching. 5. Method of patient teaching: The methods of individual patient teaching, the nurses in this study used, were conversation (55.6%) and individual discussion (19.2%) . And the methods of group patient teaching they used were demonstration (42.3%) and lecture (26.2%) They should also he prepared to use pamphlet and simple audio-visual aids for their teaching. 6. Purposes of patient teaching: The purposes of patient teaching is to help the patient recover completely, but the majority of the respondents (40.6%) don't know this. So it is necessary for them to understand correctly the purpose of patient teaching and nursing care. 7. Condition of patient teaching: The majority of respondents (75.0%) reported there were some troubles in teaching uncooperative patients. It would seem that the nurse's leaching would be improved if, in her preparation, she was given a better understanding of the patient and communication skills. The majority of respondents in the total group, felt teaching is their responsibility and they should teach their patient's family as well as the patient. The place for teaching is most often at the patient's bedside (95.6%) but the conference room (3.1%) is also used. It is important that privacy be provided in learning situations with involve personal matters. 8. Evaluation of patient teaching: The majority of respondents (76.3%,) felt leaching is a highly systematic and organized function requiring special preparation in a college or university, they have the idea that teaching is a continuous and ever-present activity of all people throughout their lives. The suggestion mentioned the most frequently for improving preparation was a course in patient teaching included in the basic nursing program. 9. Recommendations: 1) It is recommended, that in clinical nursing, patient teaching be emphasized. 2) It is recommended, that insertive education the concepts and purposes of patient teaching he renewed for all nurses. In addition to this new knowledge, methods and materials which can be applied to patient teaching should be given also. 3) It is recommended, in group patient teaching, we try to embark on team teaching.

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    A Research Regarding the Application and Development of Web Contents Data in Home Economics (가정과 수업의 웹 콘텐츠 자료 활용 및 개발에 관한 연구)

    • Kim Mi-Suk;Wee Eun-Hah
      • Journal of Korean Home Economics Education Association
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      • v.18 no.1 s.39
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      • pp.49-64
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      • 2006
    • The objective of this research is to see the current status of application and development of web contents data, and to suggest the way to improve the application and development of web contents data in home economics classes in middle schools. The respondents of the research were 312 middle school home economics teachers from all over the nation, and the tool was a questionnaire which consist of 22 questions about general status of the person who was answering and their recognitions and demands on the application and development of the web contents data. The major findings were as follows : 1) 88.5% of the sample responded that they accurately grasped a meaning of a class employing web contents data, and as for effects on preparation of professional study. 2) Most of the teachers were making good use of materials from the web in their classes. They responded that it maximized the efficiency of students' learning. Some didn't use the web contents in their classes. The reasons why the web contents data usage had been low were that the classrooms were not equipped properly (43.2%) and it took long time to create web contests (37.8%). 3) Kinds of web contents data that showed the most amount of usage were the presentations (48.4%), multi-media teaching materials(23.7%), and moving pictures(19.9%). 4) Teaches wanted to improve these particular materials among the web contents: family life and home, administration and environment of resources, and clothing preparation and administration. As for the lessons, teachers wanted developments of contents of lessons, generating motives, and evaluation to be by individual teachers or curriculum researchers' societies, and 30.8% were by Korea Education & Research Information Service (KERIS).

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    Management of Visitors in the Seonunsan Provincial Park through an Analysis on Visitors' Travel Motivations (탐방객 방문 동기 분석을 통한 선운산도립공원 관리 방안)

    • Sung, Chan Yong;Kim, Dong Pil;Cho, Woo
      • Korean Journal of Environment and Ecology
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      • v.30 no.6
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      • pp.1047-1056
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      • 2016
    • This study aims to provide managerial implications for provincial parks through an analysis on visitors' characteristics and motivational factors. The information was collected by surveying 290 visitors. The survey questionnaire consisted of questions regarding visitors' socioeconomic characteristics, characteristics of their travel behavior, visitors' motivation to visit the park, and the degree of satisfaction derived from visiting the park. Results show that most respondents appeared not to collect any information on the park prior to their visit. It was also seen that most visitors do not visit other tourist sites nearby, and are not aware of the Gochang UNESCO biosphere, which indicates that Gochang-gun, which is responsible for park management, needs to make more efforts to promote the park. A factor analysis on the visitors' motivation to visit the park extracted three factors to visit the Seonunsan Provincial Park: 'to hike,' 'to experience and observe nature,' i.e., nature learning field trip and camping, and 'to build and nurture bonding with family and friends.' To examine the effect of these various motivational factors had on the visitors' satisfaction level upon visiting the park, we conducted a multiple regression analysis with the three extracted factors to visit the park and the respondents' socioeconomic characteristics as independent variables, and the degree of recommendation of visiting the park as a dependent variable. The result shows found that, of the three travel factors, only the 'hiking' factor statistically significantly affected the degree of recommendation of visiting the park. This result suggests that the Seonunsan Provincial Park only satisfied hikers and failed to meet the demands for nature experience and observation. It is therefore suggested that the park managers develop new experience-based tourism programs, such as guided tours conducted by professional eco-interpreters.

    Manganese and Iron Interaction: a Mechanism of Manganese-Induced Parkinsonism

    • Zheng, Wei
      • Proceedings of the Korea Environmental Mutagen Society Conference
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      • 2003.10a
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      • pp.34-63
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      • 2003
    • Occupational and environmental exposure to manganese continue to represent a realistic public health problem in both developed and developing countries. Increased utility of MMT as a replacement for lead in gasoline creates a new source of environmental exposure to manganese. It is, therefore, imperative that further attention be directed at molecular neurotoxicology of manganese. A Need for a more complete understanding of manganese functions both in health and disease, and for a better defined role of manganese in iron metabolism is well substantiated. The in-depth studies in this area should provide novel information on the potential public health risk associated with manganese exposure. It will also explore novel mechanism(s) of manganese-induced neurotoxicity from the angle of Mn-Fe interaction at both systemic and cellular levels. More importantly, the result of these studies will offer clues to the etiology of IPD and its associated abnormal iron and energy metabolism. To achieve these goals, however, a number of outstanding questions remain to be resolved. First, one must understand what species of manganese in the biological matrices plays critical role in the induction of neurotoxicity, Mn(II) or Mn(III)? In our own studies with aconitase, Cpx-I, and Cpx-II, manganese was added to the buffers as the divalent salt, i.e., $MnCl_2$. While it is quite reasonable to suggest that the effect on aconitase and/or Cpx-I activites was associated with the divalent species of manganese, the experimental design does not preclude the possibility that a manganese species of higher oxidation state, such as Mn(III), is required for the induction of these effects. The ionic radius of Mn(III) is 65 ppm, which is similar to the ionic size to Fe(III) (65 ppm at the high spin state) in aconitase (Nieboer and Fletcher, 1996; Sneed et al., 1953). Thus it is plausible that the higher oxidation state of manganese optimally fits into the geometric space of aconitase, serving as the active species in this enzymatic reaction. In the current literature, most of the studies on manganese toxicity have used Mn(II) as $MnCl_2$ rather than Mn(III). The obvious advantage of Mn(II) is its good water solubility, which allows effortless preparation in either in vivo or in vitro investigation, whereas almost all of the Mn(III) salt products on the comparison between two valent manganese species nearly infeasible. Thus a more intimate collaboration with physiochemists to develop a better way to study Mn(III) species in biological matrices is pressingly needed. Second, In spite of the special affinity of manganese for mitochondria and its similar chemical properties to iron, there is a sound reason to postulate that manganese may act as an iron surrogate in certain iron-requiring enzymes. It is, therefore, imperative to design the physiochemical studies to determine whether manganese can indeed exchange with iron in proteins, and to understand how manganese interacts with tertiary structure of proteins. The studies on binding properties (such as affinity constant, dissociation parameter, etc.) of manganese and iron to key enzymes associated with iron and energy regulation would add additional information to our knowledge of Mn-Fe neurotoxicity. Third, manganese exposure, either in vivo or in vitro, promotes cellular overload of iron. It is still unclear, however, how exactly manganese interacts with cellular iron regulatory processes and what is the mechanism underlying this cellular iron overload. As discussed above, the binding of IRP-I to TfR mRNA leads to the expression of TfR, thereby increasing cellular iron uptake. The sequence encoding TfR mRNA, in particular IRE fragments, has been well-documented in literature. It is therefore possible to use molecular technique to elaborate whether manganese cytotoxicity influences the mRNA expression of iron regulatory proteins and how manganese exposure alters the binding activity of IPRs to TfR mRNA. Finally, the current manganese investigation has largely focused on the issues ranging from disposition/toxicity study to the characterization of clinical symptoms. Much less has been done regarding the risk assessment of environmenta/occupational exposure. One of the unsolved, pressing puzzles is the lack of reliable biomarker(s) for manganese-induced neurologic lesions in long-term, low-level exposure situation. Lack of such a diagnostic means renders it impossible to assess the human health risk and long-term social impact associated with potentially elevated manganese in environment. The biochemical interaction between manganese and iron, particularly the ensuing subtle changes of certain relevant proteins, provides the opportunity to identify and develop such a specific biomarker for manganese-induced neuronal damage. By learning the molecular mechanism of cytotoxicity, one will be able to find a better way for prediction and treatment of manganese-initiated neurodegenerative diseases.

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