• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.117-117
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• 2012

Si:Ge alloy semiconductor nanocrystals (NCs) offer challenging opportunities for integrated optoelectronics/optoplasmonics, since they potentially allow unprecedentedly strong light-matter interaction in the wavelength range of the optical communication. In this talk, we discuss the recent research efforts of my laboratory to develop optoelectronic components based on individual group IV NCs. We present experimental demonstration of the individual NC optoelectronic devices, including broadband Si:Ge nanowire (NW) photodetectors, intra NW p-n diodes, Ge NC electrooptical modulators and near-field plasmonic NW detectors, where the unique size effects at the nanometer scales commonly manifest themselves. In particular, we demonstrated a scanning photocurrent imaging technique to investigate dynamics of photocarriers in individual Si:Ge NWs, which provides spatially and spectrally resolved local information without ensemble average. Our observations represent inherent size-effects of internal gain in semiconductor NCs, thereby provide a new insight into nano optoplasmonics.

• Review of KIISC
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• v.23 no.2
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• pp.55-65
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• 2013

스마트폰, 태블릿 PC 등 2010년부터 폭발적으로 보급 확산된 스마트 디바이스의 영향으로 모바일 결제 분야에 가장 핫이슈로 떠오른 기술이 바로 NFC (Near Field communication) 기술이다. 사실, NFC 기술은 2004년부터 표준이 개발되었지만 이를 적용할 디바이스 및 서비스의 부재로 활용이 되고 있지 않다가 2011년 구글이 구글 월렛 서비스를 시작하면서 본격적으로 NFC 기반 서비스가 적용되기 시작하였다. 국내에서도 2011년 11월 명동 NFC 존 시범 사업을 통해 모바일 결제, 스마트 포스터, 스마트 주문 등 다양한 NFC 기반 서비스를 추진하였다. 이렇듯 국내외에서 다양한 NFC 기반 서비스 발굴 및 활성화에 노력을 기울이고 있기는 하지만, 보안을 고려하지 않은 서비스 제공 시 이에 대한 사고 피해는 상상을 초월할 수 있다. 특히, NFC 기반 서비스의 대부분이 사용자의 금전적 결제를 요구하는 서비스라는 점이 이를 입증해준다. NFC 기술 자체에는 보안 기능이 일부 포함되어져 있기는 하지만 NFC 기반 서비스별 보안 취약점이 존재할 수 있다. 이에 따라, 본 논문에서는 NFC 기반 서비스별 보안 위협 취약점 분석 및 해당 위협 및 취약점에 대한 기술적 제도적 보안 대책 등을 제시한다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.754-757
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• 2012

This research suggest the impacts of NFC(Near Field Communication) based Commerce. For this, this research set up NFC analysis framework in perspective of business model, analyze the impacts of NFC based Commerce on value and actors, and suggest strategic implications for NFC based business model actors.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.6
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• pp.1151-1156
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• 2001

In this paper, the electric field distribution and directivity on human head caused by portable phone is analyzed. An analysis model is composed of a human head model and the antenna mounted on the same ground plane as portable telephone size. The QMSA to load a capacitor without limitation of the electric force is used In the computational model to apply to the antenna mounted on portable phone. This antenna is designed to operate in the near of frequency 2.0㎓, is observed the radiation characteristics of the antenna and their variations as a function of distance from the human head.

• Journal of Information Technology Services
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• v.13 no.2
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• pp.83-97
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• 2014

With NFC technology, visitors can easily enjoy exhibit-related information and services. The participating firms can accumulate the visitor data and build up networks with potential visitors. This paper is to report an implementation and operation case of an NFC-based exhibition support service which creates new value as above. For this objective, we introduce the issues in constructing NFC-based exhibition support service. Moreover, we analyze visitor behaviors based on the tag touch data collected, and calculate the economic values generated. The NFC-based exhibition support service in this paper was applied to Hyundai Motors' booth in the 2013 Seoul Motor Show. This paper concludes with implications for business operators that are interested in applying NFC technology to exhibition spaces.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.637-638
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• 2008

In this paper, we describe a new guard lamp and traffic light controller using Zigbee one of near field communication. It can control guard lamp and traffic light system by wireless system. Also, it can definite in the sever system New guard lamp and traffic light using zibee system improved for waste power, an accident and management condition.

• Journal of information and communication convergence engineering
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• v.18 no.1
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• pp.33-38
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• 2020

Elasticsearch is an open source search and analytics engine that can search petabytes of data in near real time. It is designed as a distributed system horizontally scalable and highly available. It provides RESTful APIs, thereby making it programming-language agnostic. Full text search of multilingual text requires language-specific analyzers and field mappings appropriate for indexing and searching multilingual text. Additionally, a language detector can be used in conjunction with the analyzers to improve the multilingual text search. Elasticsearch provides more than 40 language analysis plugins that can process text and extract language-specific tokens and language detector plugins that can determine the language of the given text. This study investigates three different approaches to index and search Chinese, Japanese, and Korean (CJK) text (single analyzer, multi-fields, and language detector-based), and identifies the advantages of the language detector-based approach compared to the other two.

• Journal of Information Processing Systems
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• v.9 no.3
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• pp.461-476
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• 2013

Recently, smart devices for various services have been developed using converged telecommunications, and the markets for near field communication mobile services is expected to grow rapidly. In particular, the realization of mobile NFC payment services is expected to go commercial, and it is widely attracting attention both on a domestic and global level. However, this realization would increase privacy infringement, as personal information is extensively used in the NFC technology. One example of such privacy infringement would be the case of the Google wallet service. In this paper, we propose an zero-knowledge proof scheme and ring signature based on NTRU for protecting user information in NFC mobile payment systems without directly using private financial information of the user.

• Smart Media Journal
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• v.2 no.3
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• pp.54-61
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• 2013

NFC is a Near Field wireless Communication technology, comes to the fore as an important technology of Mobile Payment System with supply of devices and diffusion of services. Because of the fact that the NFC retail payment services, ticketing, smart cards are able to operate in one device, it(NFC Technology) can make disclosure of personal information and security risks. Thus, the problem of security in NFC technology is essential, and the need for research on security threats are increasing. In this paper, we wil analyze for NFC's vulnerabilities and security technology.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.435-437
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• 2013

This paper proposes a system composed of wireless sensor network and cloud to monitor storage environment of pharmaceutical products. Integration of sensor networks to cloud is an emerging architecture offering the benefits of internet for monitoring to be done easily and remotely from anywhere and anytime and at the same time freeing the sensor network from processing, analysis, computational and storage of sensor data.