• Membrane Journal
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• v.30 no.4
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• pp.228-241
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• 2020

Separators, which produces physical layer between a cathode and anode, are getting enormous attention as the quality of the separator determines the performance of lithium ion batteries (LIBs). Porous membranes based on polyethylene (PE) and polypropylene (PP) are generally utilized as the separator of LIBs because of their high electrochemical stability and suitable mechanical strength. However, low thermal resistance and wettability of PE and PP membranes limited the potential of LIBs. Operating at the temperature exceeding the melting point of membranes, the separators change their structures which lead to short circuit of LIBs. Low wettability of the separators corresponds to low ionic conductivity which increases the cell resistance. To overcome these weaknesses of PE and PP separators, different types of separator were prepared by co-electrospinning, applying coating layer, forming core shell around membrane, and papermaking method. The synthesized separator greatly enhanced the heat resistance and wettability of separator and mechanical properties like flexibility and tensile strength. In this review different type of polymer membrane used as separator in lithium ion battery are discussed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39B no.5
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• pp.281-290
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• 2014

The real-time data dissemination schemes exploit the spatiotemporal commuication approach which forwards data at the delivery speed calculated with the desired time deadline and the end-to-end distance in wireless sensor networks (WSNs). In practical environments, however, the performance of the real-time data dissemination might be degraded by additional and inevitable delay due to some holes. Namely, the holes lengthen the data delivery path and the spatiotemporal approach could not estimate a distance of the data delivery path. To deal with this, we propose A Hole Self-Organization Real-time Routing Protocol for Irregular Wireless Sensor Networks. In proposed protocol, nodes around holes could detect them at deploying phase. A hole is represented as a circle with center point and radius. This hole information is processed and provided as a form of location service. When a source queries a destination location, location provider replies certain points for avoiding holes as well as destination location. Thus, the source could set desired speed toward the destination via the points. Performance evaluation shows that provides better real-time service in practical environments.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.7
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• pp.630-642
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• 2013

To transmit vital signal stream of mobile patients remotely, it requires mobility of patient and watcher, sensing function of patient's abnormal symptom and self-organizing service binding of related computing resources. In the existing relative researches, the vital signal stream is transmitted as a centralized approach which exposure the single point of failure itself and incur data traffic to central server although it is localized service. Self-organizing middleware platform based on heterogenous overlay network is a middleware platform which can transmit real-time data from sensor device(including vital signal measure devices) to Smartphone, TV, PC and external system through overlay network applied self-organizing mechanism. It can transmit and save vital signal stream from sensor device autonomically without arbitration of management server and several receiving devices can simultaneously receive and display through interaction of nodes in real-time.

• The Journal of the Korea Contents Association
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• v.14 no.9
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• pp.267-274
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• 2014

The culture is an integral factor when we deal with the quality of life of members of society, and the cultural right is accepted as the basic right. However, the cultural right of the disabled in our society stays in the conditions of the discrimination and alienation by social prejudices and barriers against people with disabilities, and that results from the lack of understanding as a right. The aim of this study is to further raise awareness about the cultural right of the disabled as the basic human right, make it clear to be a universal right based on that, and insist on implementing 'Affirmative Action' for actualizing the disabled's cultural right to equality. The political measures derived from this study to guarantee and realize the cultural right of the disabled are as follows. First, the target extent of cultural voucher system should be expand to not recipients of national basic livelihood guarantees and near poverty groups, but all the disabled. Second, to take full charge of the cultural support of the disabled as a independent organization, it is necessary to establish Ministry of Culture, Sports and Tourism-affiliated 'Bureau of Culture for Persons with Disabilities'. Third, the nationwide survey on cultural activities and desires of the disabled periodically is required.

• The Journal of the Korea Contents Association
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• v.15 no.2
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• pp.476-488
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• 2015

The export demand for various public services of e-government is growing. This study defines the new services that are required in each step of export processes for public services in order to develop the new services for supporting the commercialization of the export public services. And the study arrives at a conclusion of the main problems and requirements of the current export processes for the public services through the previous literature, the open-ended questions and the focus group interview. The new services are divided into six steps including the general information and consultation of the export public services; specifically, 'evaluation of the export capabilities', 'information of export pubic services', 'network of export companies', 'knowledge exchange of export', 'guide map of export information' and 'place for communication'. Furthermore, the score test about importance of 14 detailed services and the ease of implement is conducted. Based on the results of the test, Portfolio Evaluation Quadrant analysis derives a conclusion that 'the guide map service of export information' in the step 5 is preferentially considered to be in need of implementation.

• Journal of the Korea Society of Computer and Information
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• v.18 no.2
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• pp.175-182
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• 2013

The purpose of this study was to investigate the factors that influence elementary school learners' participation in cyber home study, and to suggest possible solutions to problem of the participation rates. To identify the factors, we analyzed the literature and developed a questionnaire consisting of 8 possible factors and 33 items. Data gathered from 429 elementary school learners were analyzed in a logistic regression model, which was utilized to determine the probability of the learner's participation in cyber home study because of any of the identified variables. We studied the following variables: problem from learning motivation & attitude, burden from computer, difficulty of new learning method, problem from instructional design, difficulty of interaction, problem from screen design, and problem from learning environment. The results indicated that two factors were important: burden from computer, difficulty of new learning method. That is to say, having a low level of burden of computer and difficulty of new learning method helps improve the rate of elementary school learners' participation in cyber home study.

• International Commerce and Information Review
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• v.18 no.1
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• pp.55-78
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• 2016

This paper discusses on Electronic Payment System between U.S.A. and Canada. In particular, I focused on ACSS compare with FedACH(Fed Automated Clearing House) to advance a research effects. Because both of them is a low-value, high-volume retail payment system which their countries represent. The ACSS(Automated Clearing Settlement System) is the system through which the vast majority of CPA payment items are cleared, through various payment streams. In 2014, ACSS system cleared approximately 6.8billion payments worth a total value of $ 44.9 trillion. While, The FedACH Network are the center of America Commerce, moving more than $40 trillion each year. That's made up of almost 23 billion electronic financial transaction, including direct deposit via ACH, social security and government benefits, electronic bill payments such as utility and mortgage payments. Thus in this article, first of all, I considered features of payment system and the types of payment items between ACSS and FedAch. Second, I analyzed the status of central bank and legal background. Third, I focused on the operational policy and risk aversion policy. Lastly, I suggested that their payment and banking system have to assume, with good reason, more efficiently accurately and securely operation to protect their customer from credit risk and financial fraud.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.3 no.1
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• pp.14-25
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• 1992

The present study was purposed to find out variables of childhood antisocial behavior. The variables consisted of social cognition competence(Peer perception. acquaintance perception, frustration situation perception). academic competence(Visual integration function. written expression function, grammar closure function). The subject in this study were 32 nine year old-fourteen year old antisocial behavior boys and 32 third grade in elementary school-second grade in middle school normal boys and girls. The results of this study were obtained as follows. 1) In peer perception antisocial behavior children perceived peer as more supportive than normals. In acquaintance perception. there was no difference between groups. 2) In frustration situation perception, normal children used intropunitive attack still more than antisocial behavior children and antisocial behavior children perceived frustration situation more sensitive than normals and they were less active in problem solving aspects than normals. 3) In Academic competence, antisocial behavior children have deficits in visual motor integration function, written expression function. grammar closure function.

• The Journal of Korean Association of Computer Education
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• v.5 no.1
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• pp.1-16
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• 2002

The development of information and communications technologies(ICT) is changing school education, which is a center of teaching/lession process. Information and communications technologies can not guarantee quality education appropriate for knowledge & information society. Interactions between ICT and educational environment, change in the role of teachers, and shift in teaching strategies for educational contents and learning method would be required. This paper has studied the relationship between school education and ICT, change in the role of teachers, and a direction in teaching strategies to take advantage of ICT in school education. For this purpose, it has endeavored to offer an ideal ICT environment by researching both some cases in the foreign countries and the seventh educational process in Korea. In conclusion, this study recommends the followings; First, interactive environment between school and ICT is necessary to make education appropriate to knowledge-information society; Secondly, in the structutive teaching/learing process based upon ICT classroom, teachers should not be the old role player, such as knowledge transfer and learning manager any longer; instead, they should stimulate more social and conversational thinking, and integrate ICT into teaching process; Thirdly, teaching strategies need to change for the purpose of promoting evaluative thinking productive thinking creative thinking.

• Nuclear Engineering and Technology
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• v.17 no.4
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• pp.290-301
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• 1985

600MW(e) CANDU Primary Heat Transport System (PHTS) is composed of the two “figure-of-eight” loops and is designed to operate with the 4% Reactor Outlet Header (ROH) quality at its rated power. This existence of the two compressible regions and the positive flow-qualitly-void feedbacks are the sources of the PHTS flow instability. To ensure the PHTS stability, ROH-ROH interconnect pipes are installed as passive systems. This paper describes the investigation of the PHTS flow instability at its design full power condition. Also studied are the interconnect effect and the inherent system damping effect on the system stability. The time domain stability analyses are accessed by using the ATHER/MOD-I code which is the improved version of the KAERI developed ATHER code. Under the most adverse system modelling, the “figure-of-eight” symmetric loop shows divergent flow oscillations. Under with the interconnect, the PHTS stability is remarkably enhanced so that the system becomes stable. However, even under the conservative pressurizer modelling, the PHTS shows the more convergent flow oscillations. With the interconnect and the pressurizer modelling, its stability is highly credited. Conclusively, the inherent system damping by pressurizer itself can credit the PHTS stability without the interconnect.