• Archives of design research
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• v.11 no.1
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• pp.303-312
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• 1998

Recently, with the excessive uses of Internet, virtual spaces for the on-line introduced VRML are emerging. The inhabited virtual world includes a complex process and human experiences. The VR interactivity is now being examined, and it is the important aspect for creating VR application which may include navigating the virtual world, turning features on and off, and interacting with other users. Therefore, the study of this field is favored with a competitive advantage to the present and future multimedia designer. Thus, the subject of this thesis is for the design of virtual world, focusing on interactivity. The contents include the types of the VR interactivity, and their classifying and studying, according to the existing theories based on the literature and web sites. The types are for the user navigation, for the user interactions with other users and objects, and for the creation of metaphors. As the results of this study, it is suggested the effective application and the proposal.

• The Mathematical Education
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• v.45 no.2 s.113
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• pp.191-204
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• 2006

Computer technology has a potential to change the contents of school mathematics and the way of teaching mathematics. But in our country, the problem whether computer technology should be introduced into mathematics classroom or not was not resolved yet. As a tool, computer technology can be used by teachers who are confident of the effectiveness and who can use it skillfully and can help students to understand mathematics. The purpose of this study was to investigate the effective way to introduce and utilize computer technology based on the status quo of mathematics classroom setting. One possible way to utilize computer technology in mathematics classroom in spite of the lack of computer and the inaccessibility of useful software is using domain specific simulation software like 'Polyhedron'. 'Polyhedron', as we can guess from the name, can be used to explore regular and semi regular polyhedra and the relationship between them. Its functions are limited but it can visualize regular polyhedra, transform regular polyhedra into other polyhedra. So it is easier to operate than other dynamic geometry software like GSP. To investigate the effect of using this software in mathematics class, three classes(one in 6th grade from science education institute for the gifted, two in 7th grade) were chosen. Activities focused on the relationship between regular and semi regular polyhedra. After the class, several conclusions were drawn from the observation. First, 'Polyhedron' can be used effectively to explore the relationship between regular and semi regular polyhedra. Second, 'Polyhedron' can motivate students. Third, Students can understand the duality of polyhedra. Fourth, Students can visualize various polyhedra by reasoning. To help teachers in using technology, web sites like NCTM's illuminations and NLVM of Utah university need to be developed.

• The Journal of the Korea Contents Association
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• v.15 no.11
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• pp.501-508
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• 2015

Most web sites, information systems use the ID/Password technique to identify and authenticate users. But ID/Password technique is vulnerable to security. The user must remember the ID/Password and, the password should include alphabets, numbers, and special characters, not to be predicted easily. User also needs to change your password periodically. In this paper, we propose the user authentication method that the user authentication information stored in the external storage to authenticate a user. If another person knows the ID/Password, he can't log in a system without the external storage. Whenever a user logs in a system, authentication information is generated, and is stored in the external storage. Therefore, the proposed user authentication method is the traditional ID/Password security technique, but it enhances security and, increases user convenience.

• Journal of Korean Medicine Rehabilitation
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• v.25 no.2
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• pp.89-96
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• 2015

Objectives This study is to investigate domestic trends of chuna manual therapy on traffic accident for recent 10 years. Methods We searched the studies on chuna manual therapy for traffic accident in 6 Korean web databases. Consequently, 17 research papers were founded. We analyzed these papers according to their published year, the titles of journal, the type of study, the number of cases, the sites of injury, assessment scales of study, and ethics of research. Results 17 papers were published since 2005. The studies on chuna manual therapy about traffic accident were mainly published in the journal of korean society of chuna manual medicine for spine & nerves and the journal of korean medicine rehabilitation. All papers were clinical research include 2 case series, 2 non randomized controlled trials (NRCTs), 13 randomized controlled trials (RCTs). The most frequently occured symptom was neck pain. In assessment scales, visual analog scale (VAS) was mainly used. All clinical studies were not mentioned about approval of institutional review board (IRB). Conclusions In this study, we analyzed the trends of chuna manual therapy on traffic accident in Korea from 2005 to 2014. In reviewing published papers, we found several weak points in methods of research and quality of study protocol. It is needed to adjust these problems for development of future researches.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.4
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• pp.838-847
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• 2017

CNG which was released as a substitute of the previous CAPI (Cryptography API) library from Microsoft is constructed with individual modules based on the plug-in architecture, this means CNG is exceedingly helpful in the cost of development as well as the facility of extension. On the opposite side of these advantages, considerations on security issues are quite insufficient. Therefore, a research on security assurance is strongly required in the environment of distributing and utilizing the CNG library, hence, we analyze possible security vulnerabilities on the CNG library. Based on analyzed vulnerabilities, proof-of-concept tools are implemented and vulnerabilities are verified using them. Verified results are that contents of mail, account information of mail server, and authentication information of web-sites such as Amazon, E-bay, Google, and Facebook are exposed in Outlook program and Internet Explorer program using CNG library. We consider that the analyzed result in this paper can improve the security for various applications using CNG library.

• Korean journal of communication and information
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• v.40
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• pp.45-79
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• 2007

This study explored three questions: (1) what are the motives of producing and using user-created contents (UCC, video clips which are produced and uploaded at various web sites by individuals), (2) what are the gratifications that users obtain from UCC, and (3) what are the differences of gratifications according to individual uses of UCC. A survey was conducted to 258 UCC users and data were factor-analyzed to find the dimensions of motives and gratifications. As for the motives of UCC uses, six factors were constructed: self-expression, private life, participation, information retrieval, rest, and entertainment, among which self-expression showed the largest variation. As for the gratifications, five factors were constructed: self-expression, rest, information retrieval, socializing, and entertainment.

• Journal of the Korean Chemical Society
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• v.54 no.4
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• pp.465-470
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• 2010

Using interesting video clips corresponding to lesson subjects for students who favour visual representation is one of the good methods to enhance students' preference for science class. There are many moving picture web sites to get video clips easily via internet and 'YouTube' is very popular and one of the largest reservoir. In this study, every student in the 'Chemistry I' class, which is a class for 11th grade, was requested to search a video clip corresponding to lesson subjects and to make a presentation in the class. After 1st semester, students' response about the class using YouTube was examined by survey. As a result, students preferred and were interested in the class using YouTube than class centered on textbook. And students preferred YouTube clips showing unusual experiments that were related with contents of subject. In addition, experiments and watching their real phenomena were an interesting factor and helpful factor of learning chemistry in YouTube video clips, respectively. However, translation of English used in the video clips seemed to be a difficult part for students.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.549-552
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• 2013

The research conducted here focuses on the definition and organization of information privacy concerns in e-commerce process. Based on the identified concept of information privacy concerns(IPC), this study additionally explores the interrelationships among consumers' individual characteristics(self-efficacy, digital literacy, customer alienation), customer satisfaction and intention to buy. Through empirical model analysis, this study found that self-efficacy and digital literacy affect negatively IPC, while customer alienation has an positive effect on IPC. IPC affects positively customer satisfaction. Academically, this study extends IPC to an empirical research model by identifying the conceptualization and organization of IPC. Moreover, practically, e-commerce providers can develop how to relieve IPC of online consumers.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38B no.5
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• pp.410-415
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• 2013

Recently, as Internet enters WEB 2.0, many social network services through such as Facebook, Twitter and Youtube appeared. In these social network sites, users can easily make friends, join groups and access others personal information. Therefore, a malicious user can easily gather information of others. In order to protect user's personal information from the unauthenticated users, we propose privacy protection mechanism based on key assignment and user's trust level. A master-key is generated for each users and is segmented into a core-key and several sub-key. The master-key stores at the information owner's side and the sub-key will be distributed to requestor according to the relation and trust level. At last, in order to proof the efficiency, the performance of our proposed mechanism is compared with those of existing mechanisms.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.8
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• pp.579-585
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• 2013

Persistent Organic Pollutants (POPs) are chemical substances which persist in the environment, bioaccumulate through the food web, and pose a risk of causing adverse effects to human health and the environment. POPs are thermally stable, highly lipophilic and water-insoluble compounds which can induce various toxic influences including immunotoxicty, carcinogenicity adverse effects on reproduction, development and endocrine fuctions. Polybrominated diphenyl ethers or PBDEs, are organobromine compounds that are used as flame retardant. Because of their toxicity and persistence, the industrial production of some PBDEs is restricted under the Stockholm Convention, a treaty to control and phase out major POPs. In this study, PBDEs was measured in various site of Sihwa industrial complex to investigate concentration distribution of POPs. The levels of PBDEs in house dust samples were 0.722~44.024 ng/g-dry. In PBDEs congener, BDE-209 was relatively higher in the all sites. The concentration of BDE-209 measured over 80.0% of total PBDEs. In various site, high molecular PBDEs homologues are measured higher than low molecular.