• Journal of IKEEE
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• v.17 no.3
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• pp.385-392
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• 2013

In this paper, microstrip antenna to enhance the isolation between transmitting port and receiving port under the proximity objects is proposed, and applied to the Doppler radar sensor working at 5.8GHz ISM band which detects vital signals of a human body. Two 3dB quadrature hybrids are placed around radiation patch to form a balanced structure between transmitting port and receiving port, such that it consistently provides enhanced Tx/Rx isolation and excellent return loss over nearby objects. It is theoretically analyzed and simulated to verify the validity of the proposed application. The fabricated antenna that is 2mm away from the human body, has more than 16 dB return loss and at least 30dB isolation over ISM frequency band of 5.8GHz.

• Korean Business Review
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• v.19 no.1
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• pp.193-221
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• 2006

Customer Contact, defined as "the extent of interpersonal interaction between customer and service provider", is recognized as an important contributor to the perception of service quality, which in turn brings positive impacts on customer satisfaction, customer retention and loyalty especially in service contexts. The major purposes of this study are to explore the dimensionality of customer contact construct, to access the influences of customer contact dimensions on service quality dimensions, and to evaluate the relative importance of customer contact dimensions on service quality. Data from 388 customers of hotels at youngdong area in Kangwon-do were analyzed with major findings and their implications for service companies including hotels are as follows. First of all, the results of factor analysis show that customer contact is constructed with two dimensions, namely communication time and contact proximity. Secondly, overall customer contact is found to have positive effects on customers' perception of overall service quality and each dimension of customer contact has significant effects on overall service quality. Third, contact proximity dimension has relatively more important contributors than communication time has on overall service quality and four dimensions of service quality.

• Journal of Electrical Engineering and Technology
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• v.12 no.1
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• pp.335-345
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• 2017

Recently, location systems using RFID technology have been studied in indoor environments. However, the existing techniques require high computational cost to compute the location of a moving object because they compare the location proximity of all reference tags and objects. In this paper, we propose an RFID based location positioning scheme using event filtering, which reduces the computation cost of calculating the locations of moving objects while maintaining the accuracy of location estimation. In addition, we propose an incremental location update policy to reduce the location update cost for moving objects. We also compare the proposed scheme with one of the localization schemes, LANDMARC using a performance evaluation. As a result, the proposed scheme outperforms LANDMARC in terms of the computational cost of location estimation. The proposed scheme also reduces the cost of location update by using the RFID-based update policy.

• Korean Journal of Child Studies
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• v.24 no.5
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• pp.105-118
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• 2003

Construction of the Prosocial Behavior Scale for young children(PBSYC) was based on document research and interviews with kindergarten teachers and child development specialists. After 200 kindergarten teachers evaluated the 42 items of the PBSYC, factor analysis was conducted; items were categorized into seven factors: leadership, helping, communication, concern, proximity, sharing and empathy. As factors showed high correlation. The prosocial behavior of 306 4 to 5 year old children was measured with the PBSYC and compared with the Babock, Hartle & Lamme(l995) scale. The resulting correlation between the 2 scales was .764. Further tests indicate that the PBSYC is a valid and reliable scale for the measurement of prosocial behavior in young children.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.5
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• pp.1471-1483
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• 2023

One of the fastest-growing mobile services accessible today is mobile payments. For the safety of this service, the Near Field Communication (NFC) technology is used. However, NFC standard protocol has prioritized transmission rate over authentication feature due to the proximity of communicated devices. Unfortunately, an adversary can exploit this vulnerability with an antenna that can eavesdrop or alter the exchanged messages between NFC-enabled devices. Many researchers have proposed authentication methods for NFC connections to mitigate this challenge. However, the security and privacy of payment transactions remain insufficient. We offer a privacy-preserving, anonymity-based, safe, and efficient authentication protocol to protect users from tracking and replay attacks to guarantee secure transactions. To improve transaction security and, more importantly, to make our protocol lightweight while ensuring privacy, the proposed protocol employs a secure offline session key generation mechanism. Formal security verification is performed to assess the proposed protocol's security strength. When comparing the performance of current protocols, the suggested protocol outperforms the others.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.5
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• pp.525-536
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• 2014

Recently, the first generation of mass production of FinFET-based microprocessors has begun, and scaling of FinFET transistors is ongoing. Traditional capacitance and resistance models cannot be applied to nonplanar-gate transistors like FinFETs. Although scaling of nanoscale FinFETs may alleviate electrostatic limitations, parasitic capacitances and resistances increase owing to the increasing proximity of the source/drain (S/D) region and metal contact. In this paper, we develop analytical models of parasitic components of FinFETs that employ the raised source/drain structure and metal contact. The accuracy of the proposed model is verified with the results of a 3-D field solver, Raphael. We also investigate the effects of layout changes on the parasitic components and the current-gain cutoff frequency ($f_T$). The optimal FinFET layout design for RF performance is predicted using the proposed analytical models. The proposed analytical model can be implemented as a compact model for accurate circuit simulations.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.568-570
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• 2013

NFC represents the 2nd generation of the proximity contact-less technology, which beyond the RFID, supports peer-to-peer communication, and enables consumer access to aggregated services, anytime, anywhere, with any type of consumer stationary and mobile devices. NFC is a short range device wireless technology designed to exchange data, initiate connections with other wireless networks and act as a secured smart key for access to services such as cashless payment, ticketing, on-line entertainment and access control. In this paper, the NFC services for social networking applications are studied, and the signal flow of SNS application based on NFC P2P for smart devices and server model is proposed.

• Journal of Intelligence and Information Systems
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• v.19 no.4
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• pp.133-146
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• 2013

While the use of internet is routine nowadays, users receive and share information through a variety of media. Through the use of internet, information delivery media is diversifying from traditional media of one-way communication, such as newspaper, TV, and radio, into media of two-way communication. In contrast of traditional media, blogs enable individuals to directly upload and share news, which can be considered to have a differential speed of information diffusion than news media that convey information unilaterally. Therefore this Study focused on the difference between online news and social media blogs. Moreover, there are variations in the speed of information diffusion because that information closely related to one person boosts communications between individuals. We believe that users' standard of evaluation would change based on the types of information. As well, the speed of information diffusion would change based on the level of proximity. Therefore, the purpose of this study is to examine the differences in information diffusion based on the types of media. And then information is segmentalized and an examination is done to see how information diffusion differentiates based on the types of information. This study used the Bass diffusion model, which has been frequently used because this model has higher explanatory power than other models by explaining diffusion of market through innovation effect and imitation effect. Also this model has been applied a lot in other information diffusion related studies. The Bass diffusion model includes an innovation effect and an imitation effect. Innovation effect measures the early-stage impact, while the imitation effect measures the impact of word of mouth at the later stage. According to Mahajan et al. (2000), Innovation effect is emphasized by usefulness and ease-of-use, as well Imitation effect is emphasized by subjective norm and word-of-mouth. Also, according to Lee et al. (2011), Innovation effect is emphasized by mass communication. According to Moore and Benbasat (1996), Innovation effect is emphasized by relative advantage. Because Imitation effect is adopted by within-group influences and Innovation effects is adopted by product's or service's innovation. Therefore, ours study compared online news and social media blogs to examine the differences between media. We also choose different types of information including entertainment related information "Psy Gentelman", Current affair news "Earthquake in Sichuan, China", and product related information "Galaxy S4" in order to examine the variations on information diffusion. We considered that users' information proximity alters based on the types of information. Hence, we chose the three types of information mentioned above, which have different level of proximity from users' standpoint, in order to examine the flow of information diffusion. The first conclusion of this study is that different media has similar effect on information diffusion, even the types of media of information provider are different. Information diffusion has only been distinguished by a disparity between proximity of information. Second, information diffusions differ based on types of information. From the standpoint of users, product and entertainment related information has high imitation effect because of word of mouth. On the other hand, imitation effect dominates innovation effect on Current affair news. From the results of this study, the flow changes of information diffusion is examined and be applied to practical use. This study has some limitations, and those limitations would be able to provide opportunities and suggestions for future research. Presenting the difference of Information diffusion according to media and proximity has difficulties for generalization of theory due to small sample size. Therefore, if further studies adopt to a request for an increase of sample size and media diversity, difference of the information diffusion according to media type and information proximity could be understood more detailed.

• Asia pacific journal of information systems
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• v.10 no.4
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• pp.57-75
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• 2000

Most current literature on knowledge and technology transfer(Appropriability Model, Dissemination Model, and Knowledge Utilization Model), describe the process of transfer in details, but has limitation in terms of their application in contemporary high-tech industries since most studies have not provided plausible explanation on levels and factors affecting transfer of knowledge and/or technology. To overcome these limitations, the four levels of knowledge and technology transfer are suggested: Knowledge and Technology Creation(Level I), Sharing(Level II), Implementation(Level III), and Commercialization(Level IV). Comprehensive literature identifies sixteen variables affecting the process and results of knowledge and technology transfer. The survey results show four key factors in knowledge and technology transfer: Communication, Distance, Equivocality, and Motivation, Communication refers to the degree to which a medium is able to efficiently and accurately conveys task-relevant information and media while distance involves both physical and cultural proximity. Equivocality refers to the degree of concreteness of knowledge and technology to be transferred while motivation involves incentives for and the recognition of the importance of knowledge and technology transfer activities. Further analysis shows that there are four distinctive clusters and they show very contrasting characteristics in terms of four key factors. The careful mapping of the four clusters on the four key factors show very informative knowledge and technology transfer patterns, the Knowledge and Technology Transfer Grid. Finally, actions to increase communication interactivity and motivation, and to reduce cultural distance and equivocality are suggested.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.10
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• pp.2256-2262
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• 2015

Recently, device-to-device (D2D) communication has been considered as key technology for future cellular system, because it can solve the problem of excessive data traffic increment and can also provide new communication services. Herein, we propose new neighbor discovery for D2D communication and examine its performance. Our proposed scheme is proximity beacon based discovery in which wireless resource for pilot transmission is assigned based on the spatial correlation of wireless channel and sensing period is adjusted according to target accuracy such that power consumption can be reduced. The performance of our propose scheme is analyzed mathematically and verified through computer simulations.