나노입자 적층시스템을 이용한 전기변색소자의 제작 및 대면적(1m2급) 전기변색유리의 변색시간 모델링

학위논문 (박사)-- 서울대학교 대학원 : 공과대학 기계항공공학부, 2018. 2. 안성훈.Electrochromism refers to a color change under an externally applied voltage. Increasing interest in this phenomenon has led to new manufacturing processes for electrochromic devices (ECDs). Herein, major processes are introduced and compared in terms of their process parameters. The six representative fabrication processes discussed in this paper are electrodeposition, sol-gel, spray pyrolysis, chemical vapor deposition (CVD), thermal evaporation deposition and sputtering. Commercialization of ECDs requires a consideration of environmental issues, cost, performance and scale of manufacture. Therefore, in this study, we fabricated ECDs using a novel nanoparticle deposition system (NPDS), a seventh fabrication process. It is a low-cost eco-friendly process. The possibility of commercialization of the NPDS is discussed. Deposition of tungsten oxide (WO3) thin films on fluorine-doped tin oxide (FTO) and indium tin oxide (ITO) substrates was conducted using the NPDS. This is a deposition approach based on low-vacuum air-spraying at room temperature. The structure of the WO3 films was characterized using X-ray diffraction, and the surface morphology was investigated using scanning electron microscopy and atomic force microscopy. The electrochemical properties of the films were examined using cyclic voltammetry and chronocoulometry. The ECD was fabricated using the deposited WO3 film, a counter electrode and an electrolyte. When a predetermined voltage (3 V) was applied, the color of the prepared WO3 films changed from transparent yellow to dark blue, demonstrating electrochromism. The WO3 film exhibited an optical contrast of up to 50% at a wavelength of 800 nm. After confirming the feasibility of using the NPDS for fabricating ECDs, we constructed a large-area NPDS and used it to produce large-area electrochromic windows (ECWs). The conventional response-time model showed a large difference from the actual value with increasing ECW active area. To overcome this problem, a new electrochromic response-time model based on the transient response of a resistance–capacitor (RC) direct-current (DC) circuit was developed. This model provided an estimation of the coloration time of ECWs as a function of the size of the active area. Five samples of different sizes were prepared: 10 x 10 mm2, 50 x 50 mm2, 300 x 300 mm2, 500 x 500 mm2 and 1 x 1 m2. We then measured the current and transmittance variation of the fabricated ECWs during coloration. The response time was defined in terms of the current difference. The response model defined the RC value as proportional to the length of one side of the active area of the ECW. The estimates derived using the response model were in good agreement with measured data for relatively large ECWs. A plasma process was introduced into a conventional NPDS to improve the contrast of the ECDs. Plasma is the fourth material state in which gas molecules are ionizedit is used for electrically or chemically modifying object surfaces. Plasma treatment of WO3 particles decreased the contact angle of the WO3-deposited surface. This meant that the contact area between the WO3-deposited surface and the electrolyte had increased. Moreover, the WO3 surface crystal structure became more amorphous. These effects improved the contrast from 50 to 65.9%.Chapter 1. Introduction 1 1.1 Overview 1 1.2 Principles of electrochromic devices (ECDs) 2 1.3 Current fabrication trends of ECDs 3 1.4 Fabrication methods of ECDs 7 1.4.1 Electrodeposition 7 1.4.2 Sol-gel processes 10 1.4.3 Spray pyrolysis 19 1.4.4 Chemical vapor deposition (CVD) 21 1.4.5 Thermal evaporation deposition 26 1.4.6 Sputtering 28 1.4.7 Nanoparticle deposition system (NPDS) 36 1.5 Summary of processes 37 1.6 Process information tables 41 Chapter 2. ECD fabrication using NPDS 46 2.1 Overview 46 2.2 Experiments 47 2.3 Results and discussion 51 2.3.1 Optical transmittance 51 2.3.2 X-ray diffraction analysis 55 2.3.3 Surface morphology and film thickness 56 2.3.4 Electrochemical properties 59 2.4 Summary of ECDs fabricated using NPDS 61 Chapter 3. Large-area ECWs and response time model 62 3.1 Overview 62 3.2 NPDS enlargement for large area applications 62 3.3 Fabrication of large area electrochromic windows (ECWs) 65 3.4 Response model 69 3.5 Comparison between calculated and measured response time 75 3.5.1 Electrochromic current 75 3.5.2 Optical transmittance 77 3.5.3 Evaluation of the response time model 78 3.6 Summary of response time model for large-area ECWs 82 Chapter 4. Plasma-assisted NPDS 83 4.1 Overview 83 4.2 System design and configuration 84 4.3 Evaluation 86 4.3.1 Results of WO3 powder deposition 87 4.3.2 Results of electrochromic performance 91 4.4 Summary of plasma-assisted NPDS effects 92 Chapter 5. Conclusion 93 Bibliography 95 Abstract 110Docto

An Analysis of Employment Effects by the Policy for the University Entrepreneurship Education Ecosystem

본 논문은 정부의 ‘대학 창업교육 5개년 계획을 통한 청년창업 활성화 방안’에 제시되어 있는 과제를 대상으로 어떤 전략이나 과제가 더 중요한지에 대한 우선순위를 도출하고, 우선순위별로 제도개선이 이루어질 경우 대학창업은 얼마나 늘어나게 될 것인지를 분석하였다. 본 논문의 주요 연구결과는 다음과 같다. 첫째, 3대 전략의 중요도 가중치를 보면, ‘대학창업 여건 및 창업 인식 개선’이 0.368로 가장 높고, ‘대학생 창업 도전을 위한 환경 조성’이 0.333, ‘창업 친화적 대학 교육제도 마련’이 0.299인 것으로 나타났다. 둘째, 창업과 관련한 제도와 환경이 현재대로 지속된다(Business As Usual; BAU)고 하더라도, 지속적으로 학생 창업이 증가할 것으로 전망된다. 셋째, 각 대학이 바라는 대로 제도개선이 이루어질 경우, 2017년에 BAU 대비 학생 창업인원은 1,039명이 늘어나는 것으로 전망된다. 넷째, 시나리오 분석의 결과를 보면, 상위요인 ‘대학생 창업 도전을 위한 환경 조성’과 상위요인 ‘대학창업 여건 및 창업 인식 개선’ 중 하위요인인 ‘대학의 창업역량 강화’에 초점을 맞추어 제도를 대폭 개선하는 경우, 2017년에 학생 신규창업인원은 BAU 대비 415명이 더 증가할 것으로 전망되고 있다.This paper derives policy priority included in ‘University Entrepreneurship Education 5 Year Plan' and forecasts the employment effect as per policy priority. Major results of the paper are as follows: First, the policy weight of 'the improvement of university Start-up conditions and awareness' is the highest, followed by 'the creation of the environment for the challenge of the university students' new establishment' and 'the building-up of the start-up friendly education system'. Second, additionally 1,039 students are forecast to create new establishments in 2017 compared to the case of business as usual if institutional improvement is realized as every university wishes. Third, according to the scenario analysis, incrementally 415 students are expected to create new establishments in 2017 compared to the case of business as usual if policy priority is given to 'the creation of the environment for the challenge of the university students' new establishment' and some tasks of 'the improvement of university Start-up conditions and awareness'

A Review on Effectiveness of Web-Based Project Learning

본 연구는 웹기반 프로젝트학습에 관한 선행연구들을 고찰하여 젝트학습의 교수설계 전략을 탐색하고 분석하는데 그 목적을 두고 있다. 웹기반 프로젝트학습은 웹이 지닌 특성을 활용하여 프로젝트학습을 효율적 • 효과적으로 실행하는 교수 · 학습 방법이다. 웹기반 프로젝트학습에 관한 이론적 탐색을 기반으로 웹기반 프로젝트학습의 효과성에 관한 선행연구들을 다음과 같이 3가지 차원에서 고찰해 보았다. 즉，교수전략에 따른 웹기반 프로젝트학습의 효과성，학습자의 인지적·행 동적 특성에 따른 웹기반 프로젝트학습의 효과성，교과영역별·학교급별 웹기반 프로젝트학습의 효과성이다. 선행연구들을 고찰한 결과，웹기반 프로젝트학습은 자기주도적 학습전략을 사용할 수 있는 기회를 학습자에게 제공하고 성찰적인 교수전략과 내용독립전략을 사용했을 때 학습에 긍정적인 효과를 가져왔음을 알 수 있었다. 그리고, 자기주도성 수준이나 메타인지 높은 학습자들이 웹기반 프로젝트학습방법으로 학습할 경우 학업성취도에 긍정적인 효과를 가져왔다. 또한 초등학교 5학년 이상의 다양한 학교급의 학생들이 사회과나 과학과의 학습내용을 웹기반 프로젝트학습방법으로 학습할 경우 학업성취도나 학습태도에 긍정적인 영향을 미치는 것으로 밝혀졌다

A Review on the Characteristics of Communication in the Cyber-world and their Implications for New Counseling Methods.

Our society is now turning into the information society in which all the people are accustomed to utilize the internet as a vehicle to get various information for solving problems faced with their lives. The internet is installed with the combination of computer systems and telecommunication technology. The internet has the strongest power to store and deliver plenty of information. In this sense, it is called the 'sea of information' or cyber-world that provides us with new phases of communication. The purpose of this study is to review the characteristics of communication in the cyber-world and to show their implications for new counseling techniques. More specific issues of this study are as follows. First, what are the characteristics of communication and information exchange in the cyber-world? Second, what are the new counseling techniques that make use of the characteristics of the cyber-world? Third, what are the further tasks for developing the counseling discipline in the cyber-world? The conclusion of this study is summarized as follows. First, communication methods in the cyber-world can be characterized as 1) the anonymity of information sender and information receiver, 2) the openness of information that everybody can access in the cyber-world, 3) the transcendence of time and space with respect to communication, 4) simultaneous or delayed interaction of communication, 5) one-to-one counseling as well as interactive counseling between a group of counselors and a group of clients, 6) qualitative and quantitative varieties of information, and 7) opportunity of self reflection. Second, new counseling techniques based on the characteristics of communication in the cyber-world are 1) the self-counseling system which makes use of database of counseling cases, 2) real-time communication in terms of E-mail, 3) group counseling such as an on-line forum using Bulletin Board, 4) distance conferencing counseling, 5) the active participation of the clients according to the anonymity of the cyber-world, and so on Finally, the developmental tasks for future-oriented counseling techniques using cyber-world are needed: 1) new counseling theories and techniques considering the characteristics of communication in the cyber-world, 2) cumulative methods of sufficient information and management systems for setting the database, 3) training programs for sufficient cyber-counselors, 4) expert consulting systems, 5) cyber counseling systems that are client-friendly, and so on

Curriculum of Gifted Education in the United States

The purpose of this study is to review the curriculum of gifted education in the United States and to provide some implications for the development of gifted education in Korea. Major concerns of this study are as follows: 1) historical background of gifted education development, 2) policy and institution of the curriculum for gifted education, 3) instructional strategies and models for gifted education, 4) documentation system of the curriculum for gifted education, 5) goals and objectives of the curriculum, 6) program structure and management of the curriculum, 7) evaluation of the curriculum, 8) relationships between the curriculum for gifted education and the curriculum for regular school, and 9) examples of the curriculum framework. The findings and conclusions can be summarized as follows. First, gifted education in the United States has been started almost hundred years ago at Johns Hopkins University and Harvard University. Second, the Education Act for the gifted was institutionalized in 1988. Later on, it was revised and announced in 1994 such as Jacob Javits Gifted and Talented Students Education Act. In this act, general guidelines for the implementation of gifted education are included. For instance, included is the support system by the state government for the policy and institution of the gifted education. Third, various strategies and models for gifted education are identified, such as Renzulli's Triad Enrichment Model, Guilfords 'Structure of Intelligence Model', 'Multiple Menu Model' and so on. In addition, the acceleration model and enrichment model are applied as well. Fourth, documentation of the curriculum of gifted education includes at least 14 categories such as an overview, the definition of giftedness in related subject area, goals and objectives of gifted education, principles of organizing the sequence and scope of the curriculum, teaching-learning methods, the evaluation criteria for learning outcomes, and so on. Fifth, major goals of gifted education are the enhancement of creative thinking ability, reading and writing capability, active learning skills, interdisciplinary study skills, independent inquiry skills, and evaluation skills for new idea. Sixth, the program of gifted education cover from 5 to 17 years old of the gifted. In addition, the program is differentiated according to the ability level and grade level. Seventh, the evaluation of the program is conducted according to the relevance and efficiency of the curriculum for achieving the goals of gifted education. Finally, all the gifted are generally required to master the regular curriculum of the regular school. Simultaneously, the gifted have the opportunity to attend the special program such as a research project, a seminar, a workshop, a special class in order for them to enhance their potentiality. Clearly, this study showed that the characteristics and strengths of the curriculum for the gifted in the United States are open, autonomous, flexible, various, and systematic

교육의 본질 구현을 위한 교육공학의 연구방향

교육의 본질과 교육공학은 실과 바늘의 관계와 같이 상호 불가분의 관계에 놓여 있다고 볼 수 있다. 그리고 교육공학의 역할에 따라 교육의 본질이 결정되는 것이 아니라 교육의 본질에 맞추어서 교육공학의 역할이 결정된다고 보아야 할 것이다. 그러므로 교육의 본질 구현을 위해서 교육공학분야에서 어떤 연구를 수행해 나가야 되는가를 탐색해 보는 것은 가치로운 일이 될 것이다. 지난 30여 년 동안 ICT의 급진적 발전, 첨단 디지털 매체기반 학습환경, 교수학습의 구성주의적 접근, 교수체제이론과 교수설계이론의 다양화 등 교수·학습공학 분야의 놀라운 발전과 학습환경의 질적 변화가 이루어져 왔으며, 그 결과 교육의 본질과 깊은 관련을 맺고 있는 속성들인 학습자의 학습요구와 학습특성, 교육목적, 교육내용, 교육방법 등도 새로운 시각에서 연구·개발되어 왔고, 동시에 교육의 본질을 구성하고 있는 속성들의 효과적·효율적 처방에 관심을 두고 있는 교육공학 패러다임도 지속적인 변천과 진전을 이루어 왔다. 여기서는 교육의 본질의 의미와 속성을 파악해 보고, 교육의 본질과 교육공학 의 역할 간의 상호관계를 분석해 보고, 교육의 본질 구현을 위한 교육공학 패러다임의 변천을 살펴 본 후, 끝으로 교육의 본질 구현을 위한 교육공학의 새 지평을 탐색해 보고자 한다

An Inquiry on the Presentation Principles of Audio-visual Infonmation under the Multimedia-based Learning

This research reviews a cognitive theory of multimedia-based learning which is based on dual-coding thεory and cognitive load theory. According to the dual-coding theory, visually presented information is processed in visual working memory whereas auditorily presented information is processed in auditory working memory. Because the auditory and visual working memory are independent, students can hold both representations in working memory at the same time and build referential connections between them. A multimedia principle underlying to the use of multimedia in learning environment is that learners understand informations better when they receive words and corresponding pictures rather than words alone. This research suggested two principles related to the multimedia usage. Spatial contiguity principle is that learners will make appropriate connections when words and pictures are near to each other on a screen. The temporal contiguity principle is that learners are more likely to make appropriate connections when they are presented simultaneously rather than successively. According to the cognitive load theory, the processing capacities of the auditory and visual working memories are limited. When thε animation and text explanation are presented on one screen, visual working memory may become overloaded. This is because both animation and text must compete for visual processing capacity. When learners nεed to split their attention, it overburdens their limited working memory capacity. This is called split-attention effect and consists of two principles : visual and auditory split-attention effect

Review on the construct factors of Self-Regulated Learning and the results of experimental studies about Self-Regulated Learning

최근에 자기조절학습은 인간의 학습활동에 관한 연구에 있어서 핵심적 연구주제로 받아들여지고 있다. 본 연구는 교수·학습 분야에서 최근의 연구동향으로 관심이 모아지고 있는 자기조절학습의 의미를 파악하고, 자기조절학습의 구성요인 및 전략을 고찰해 본 후, 자기조절학습이 학습효과에 어느 정도 영향을 미치는지에 관하여 실증적 연구결과들을 분석해보려는 데 그 목적을 두고 있다. 문헌을 폭넓게 고찰한 결과, 자기조절학습의 주요한 세 가지 구성요인은 메타인지 요인, 학습전략 요인, 동기 요인 등인 것으로 밝혀졌으며, 이러한 요인들과 학업성취도 사이에는 정적인 상관관계가 높게 나타나는 것으로 밝혀졌다. 자기조절학습의 구성요인과 관련된 선행연구들을 고찰한 결과를 요약하면 다음과 같다. 첫째로, 자기조절학습의 구성요인 중의 하나인 메타인지 요인이 학업성취에 미치는 영향은 학습자의 특성과 연구목적에 따라서 약간의 차이를 나타내고 있지만, 메타인지수준이 높아질수록 학업성취도가 뚜렷하게 높아지는 경향이 있는 것으로 밝혀졌다. 둘째로, 학습전략 요인의 경우에는, 상당히 많은 경험적 연구들에서 학습전략의 하위요소인 인지전략 및 자원관리전략 등의 학습전략 활용이 학업성취에 긍정적인 효과를 가져오며, 또한 학습자가 상황과 환경에 적합한 학습전략의 요소를 선택하고 활용함으로써 학업성취도가 향상되는 것으로 밝혀졌다. 마지막으로, 동기 요인 측면에서 볼 때, 동기 요인의 구성요소인 자아효능감은 학업성취를 예언하는 중요한 변인으로 밝혀졌고, 내재적 가치 요소 및 시험불안 요소는 학업성취와 밀접한 관련은 있으나 높은 상관은 나타나지 않는 것으로 밝혀졌다. 앞으로의 연구과제로는 경험적 연구를 통하여 자기조절학습 구성요인들 간의 역동적 상호작용 모델을 구안해 내야 할 것이며, 학습자가 학습력 증진을 위하여 자기조절학습 구성요인들을 조작하고 활용할 수 있도록 자기조절학습 과정에 대한 세부적인 조작기법과 활용방안을 탐색해보아야 할 것이며, 자기조절 학습과정의 조작전략을 탐색하는 연구가 지속적으로 이루어져야 할 것이다.그리고 학습자와 학습환경의 다양한 특성들에 따른 자기조절학습의 과정을 분석하고, 학습자에 맞는 자기조절전략의 활용방법도 모색되어야 할 것이다. The major purposes of this study are to elaborate the concept of self-regulated learning and to inquire the major construct factors and strategies of self-regulated learning. In addition, this paper is to examine the relationship between self-regulated learning and academic achievement. Based on the review of literatures and experimental studies, it was drawn the major three construct factors of self-regulated learning such as meta-cognition, learning strategies, and motivation. Further, it was analysed the relationship among construct factors of self-regulated learning and academic achievement. It was concluded that there were positive relationships between three construct factors and academic achievement. Firstly, regarding the relationship between meta-cognition and academic achievement, the higher meta-cognition level is, the higher academic achievement is. More specifically, focusing on the learner`s characteristics like the degree of knowledge acquisition or degree of learning level, it was shown the positive relationships between meta-cognition and academic achievement. Secondly, similar to meta-cognition' results, there were higher relationships between learning strategies and academic achievement. Especially selecting and using of learning strategies' sub-variables greatly influences on academic achievement. Third, the relationship between motivation and achievement was slightly high, In other words, the motivation was a important factor which can affect to increase the academic achievement level. In short, major three factors of self-regulated learning such as meta-cognition, learning strategies, and motivation are critical to enhance the academic achievement level. Enhancing learner's self-regulated learning ability, learners are able to attain learning goals and to improve academic achievement level

Review on the Critical Components of Integrated Approaches on Creativity and Its Implications for Creativity Education

창의성의 다원적 접근은 단일 학문분야에서 벗어나 통합적 관점에서 창의성 신장에 영향을 미치는 요인들을 탐색하는 것을 말한다. 다원적 접근에서 제안된 창의성 구성 요인들을 모두 고려한다면, 개인의 창의성을 가장 효과적으로 향상시킬 수 있을 것이다. 그러나 실제로 교육현장에서 이 모든 요인들을 고려하는 것은 현실적으로 매우 어려운 일이다. 따라서 본 고찰은 교육을 통해 변화시킬 수 있고, 나아가 창의성 수준을 향상시키는데 도움이 되는 요인들을 탐색하려는데 그 목적을 두고 있다. 이러한 목적을 달성하기 위해서 창의성에 관한 다양한 다원적 접근모형들에 대해 살펴보고, 이들에 대한 비교, 분석을 통해서 창의성 교육에서 고려해야 할 주요한 창의성 구성요인들을 규명하려는데 관심을 두고 있다. 본 고찰에서는 창의성의 구성요인을 창의적 행동의 상호작용모형, 생태학적 모형, 시스템 이론, 투자이론 등의 네 가지 모형들을 중심으로 비교․분석하였다. 그 결과로 창의성 교육을 할 때 고려해야 할 요인들로는 ① 선행조건으로 가정교육, ② 인지적 능력과 관련된 요인으로 창의적 문제해결(CPS), 지식, ③ 정서와 관련된 요인으로 내재적 동기, ④ 맥락적 영향과 관련된 요인으로 개인의 특성이 반영된 과제, ⑤ 사회적 영향과 관련된 요인으로 상승적인 외적동기가 창의성 교육의 실제에서 가장 중요한 창의성 구성요인으로 밝혀졌고, 이러한 요인들을 신장시켜주게 되면 창의성이 향상될 것이다. The purpose of this research is to search for the creativity-related components which can highly affect the enhancement of student's creativity. It can be easily found to be so many components in an integrated approach to creativity, but it is really hard to apply all this components in a real educational setting. Therefore, it is very important to search for the chief components that are useful when we want to heighten creativity. To fulfill this purpose, we searched for the chief components in creativity education by comparing and analyzing four kinds of integrated approaches. The important components driven by this research are family environment, creative problem solving, knowledge, task, intrinsic motivation and synergistic extrinsic motivation. First, family environment is an important factor in creativity education. Most children undergo many early experiences in their family environment. A comfortable family environment can help children to improve their curiosity, imagination and to have rich experiences based on broad knowledge. Second, creative problem-solving and knowledge are also critical factors in creativity education. A creative problem solving education program can improve creativity more than any other creativity education program. Thus creative problem-solving can foster creativity effectively. And knowledge ought to be based in creativity education. Only physicians can effect physical changes in learning, thus knowledge is one of the most important factors in enhancing creativity. Third, intrinsic motivation such as satisfaction, interest and concentration is closely related with creativity. Fourth, subjects reflecting individual interest can help in expressing creativity effectively. Fifth, synergistic extrinsic motivation is a more important factor in creativity education than non-synergistic extrinsic motivation, which tends to suppress individual creativity

A Review on the Variables and Factors for Facilitating Inter-Personal Interaction in Web-Based Instruction

One of the valuable functions of Web-Based Instruction(WBI is that it provides with inter-personal interactive learning environment. However, web serves only as a tool offering opportunity to interact, and it doesn't guarantee the interaction. Therefore, a variety of strategies promoting the interaction should be used to enhance the effect of Web-Based Instruction. To do this, we should check first what kinds of factors influence the inter-personal interaction. We intend, in this research, to arrange comprehensively factors influencing the inter-personal interaction by researching and analyzing studies related to the interaction and categorizing related factors. As a result of the research, we have found factors related to the interaction in such various areas as learner characteristics, instruction planning and structuring, instruction conducting, learning environment, and so on. When categorized, these factors can be classified into those related to learners, teachers' instruction conducting, and learning environment. The detailed categories are assorted as follows: Learner factors are classified into two categories such as the cognitive and emotional aspect; teachers' instruction conducting factors into two categories in the instruction structuring and instruction conducting aspect; learning environment factors into two categories such as computer-related environment and connecting environment. These categories cover all the various instruction phenomena in Web-Based Instruction. The specific results of the research and their interpretation are as follows. First, factors related with the interaction in WBI are so various and wide-ranged that they include all of the diverse variables which are dealt with in teaching-learning theories. This result seems to come from the fact that an instruction by itself is carried out through the interaction. Hence, it is difficult to consider all the factors influencing the interaction in the real instruction; researches are needed that check which are more important than others in factors related to the interaction and which can be come true. Second, the critical factors influencing the interaction according to each category are as follows. As learner related factors, there are prerequisite knowledge, character, motivation, individual need of learners. Teacher related factors include the use of cooperative learning strategy, the use of face-to-face instruction, discussion topic, teacher' s feedback, teacher s modeling, and teachers participation. And environment related factors are the level network equipment, and the number and arrangement of computers. Plenty of factors have been proved to influence the interaction in the research, but up to now there haven't been enough experiment studies which treat the factors influencing the interaction directly. Thus, it is necessary to check factors influencing the interaction in Web-Based Instruction by researching directly factors related with the interaction. Third, as a result, many factors specially in instruction structuring and conducting aspect are proved to influence the interaction. This result shows that teachers' roles still have a decisive influence on the promoting of the interaction, although they regard learners' study as important and teachers' roles have turned from deliverers of content to promotors of study in Web-Based Instruction Finally, factors facilitating the interaction are categorized into learner characteristics, instruction structuring, instruction conducting, and learning environment. This categorization is made on the basis of the real situation where Web-Based Instruction is performed; thus it has actual usefulness. But, the categorization may have some problems in that it is not based on theoretical analysis. Thus, categories are needed to be altered and validated on the basis of teaching-learning theories