• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권9호
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• pp.3231-3249
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• 2014

Deniable encryption, introduced in 1997 by Canetti, Dwork, Naor, and Ostrovsky, guarantees that the sender or the receiver of a secret message is able to "fake" the message encrypted in a specific ciphertext in the presence of a coercing adversary, without the adversary detecting that he was not given the real message. Sender - side deniable encryption scheme is considered to be one of the classification of deniable encryption technique which defined as resilient against coercing the sender. M. H. Ibrahim presented a sender - side deniable encryption scheme which based on public key and uncertainty of Jacobi Symbol [6]. This scheme has several problems; (1) it can't be able to derive the fake message $M_f$ that belongs to a valid message set, (2) it is not secure against Quadratic Residue Problem (QRP), and (3) the decryption process is very slow because it is based dramatically on square root computation until reach the message as a Quadratic Non Residue (QNR). The first problem is solved by J. Howlader and S. Basu's scheme [7]; they presented a sender side encryption scheme that allows the sender to present a fake message $M_f$ from a valid message set, but it still suffers from the last two mentioned problems. In this paper we present a new sender-side deniable public-key encryption scheme with fast decryption by which the sender is able to lie about the encrypted message to a coercer and hence escape coercion. While the receiver is able to decrypt for the true message, the sender has the ability to open a fake message of his choice to the coercer which, when verified, gives the same ciphertext as the true message. Compared with both Ibrahim's scheme and J. Howlader and S. Basu's scheme, our scheme enjoys nice two features which solved the mentioned problems: (1) It is semantically secure against Quadratic Residue Problem; (2) It is as fast, in the decryption process, as other schemes. Finally, applying the proposed deniable encryption, we originally give a coercion resistant internet voting model without physical assumptions.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제8권1호
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• pp.96-106
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• 2002

HL7 (Health Level 7)은 Healthcare 환경의 이질적 시스템간에 임상 및 관리정보의 교환을 가능하게 하는 국제 표준 프로토콜로서 표준 인코딩 규칙에 따른 다양한 HL7 메시지 양식을 정의하고 있다. 본 논문에서는 메시지 객체 모델(Message Object Model)과 메시지 정의 저장소(Message Definition Repository)를 이용하여 유연성, 재사용성, 확장성이 탁월한 HL7 인코딩/디코딩 프레임워크의 설계 및 구현을 제시한다. 메시지 객체 모델은 HL7 메시지를 구성하는 객체들과 그들 간의 다양한 관계를 나타내는 추상적 HL7 메시지 양식으로서, 세그먼트, 필드, 컴포넌트 등과 같은 HL7 메시지의 표준 구성요소들 간의 논리적 관계를 반영하는 동시에 표준안에 의해 규정된 구조적 제약사항을 만족하도록 하여 준다. 메시지 객체 모델은 플랫폼 종속적인 데이터 양식과 상관없이 독립적으로 HL7 인코더와 디코더를 구축할 수 있도록 하여 주기 때문에 최소의 노력으로 임의의 이질적 병원 정보 시스템들을 상호 연결할 수 있도록 한다. 한편, HL7 메시지들을 정의하고 있는 외부 데이터베이스인 메시지 정의 저장소는 표준 HL7 메시지 양식이 수정되더라도 인코더와 디코더의 구현이 영향을 받지 않게 하여 준다. 게다가, 메시지 정의 저장소는 인코더와 디코더 각각의 입력(즉, 메시지 객체 모델로 표현된 HL7 메시지 객체와 인코딩된 HL7 메시지 문자열)에 대하여 합법성 여부를 조사하는 데 유용하게 사용된다. 본 논문에서는 프로토타입 HL7 인코더와 디코더의 구현을 위해 JAVA를 이용하였지만, 제시된 인코딩/디코딩 프레임워크는 인코더와 디코더를 ActiveX, JAVABEAN 또는 CORBA 객체 등과 같이 독립된 표준 컴포넌트로서 쉽게 구현될 수 있도록 하여 준다.

• 산경연구논집
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• 제10권10호
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• pp.53-65
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• 2019

Purpose - Current study aimed at investigating the effects of the choice easiness as a thought triggered at the time of making decision and the goal achievement emotion as a prediction of how consumers feel in the state of achieving consumption goal on brand purchase intention. And It also explored moderation role of incidental pride type such as ambient hubris pride and ambient authentic pride felt before the event in the effects of message type such as self-verifying message and self-enhancing message on the choice easiness and the goal achievement emotion. Research design, data, and methodology - Message type was divided into self-verifying message and self-enhancing message. Incidental pride type was divided into hubris and authentic pride. Smart mobile phone was selected for empirical study. And the experiment was performed with 2(pride type: hubristic versus authentic) × 2(message type: self-verifying message versus self-enhancing message) between-subjects design. Questionnaires from 215 undergraduate students were used to test hypotheses by Macro process model 7. The hypotheses were tested at each of self-verifying message group and self-enhancing message group. Results - First, both choice easiness and goal achievement emotion positively influenced on the purchase intention at both self-verifying message group and self-enhancing message group. Second, at self-verifying message group, the positive effects of self verification on both choice easiness and goal achievement emotion were higher to the customers under incidental hubris pride than to those under incidental authentic pride customers. Third, at self-enhancing message group, the positive effects of self enhancement on goal achievement emotion were higher to the customers under incidental authentic pride than to those under incidental hubris pride. However, at self-enhancing message group, the positive effects of self enhancement on choice easiness (goal achievement emotion) were not higher (higher) to the customers under incidental authentic pride than to those under incidental hubris pride. Conclusions - Focusing on the results of this study, to promote their brand purchase intention, brand managers should use self-enhancing message to induce goal achievement emotion from incidental authentic pride customers. And the brand managers should develop and use self-verifying message to induce choice easiness as well as goal achievement emotion from hubris pride customers, which in turn, promote their brand purchase intention.

• 경영과정보연구
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• 제24권
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• pp.97-124
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• 2008

This study aimed to explore how the involvement of environment influenced eight subjects group. Thus, experiment was performed to clarify the role that the attitude of university student consumer plays in the communication process depending on the level of engagement of consumer in the environment and method to raise donation for preservation of environment. Analyzing as per the type of appeal, the mark in altruistic appeal type was higher in all variables than egoistic appeal type. Finally, checking the average mark of each variable as per the condition of donation, the value in unconditional donation was higher than in all variables than conditional donation. It was found 3 groups composed of 2 groups with high level of environmental engagement and 1 group with low level of environmental engagement were suitable to double mediation model among the 8 experimental groups. The group where double mediation model best corresponds than any other group was high level related to environment and the group that contacts altruistic appeal and the message in the form of conditional donation. It was also found that the group that has low level of environmental engagement and contacts egoistic appeal type and conditional donation shows the group that corresponds to double mediation model in the second place among the 8 groups. Finally, it was found that the group that has high level of environmental engagement and is stimulated by altruistic appeal and unconditional donation corresponds to double mediation model. Depending on the condition of message stimulation, unconditional donation is found to better correspond to double mediation model than conditional donation. However, opposite phenomena is observed when the level of environmental engagement is high and appeal type is egoistic. Namely, it was found that conditional donation better corresponds to double mediation model than unconditional donation.

• 정보처리학회논문지D
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• 제15D권5호
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• pp.659-668
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• 2008

최근 컴포넌트 간의 약 결합을 지원하는 Exogenous 커넥터 기반의 컴포넌트 모델이 제안되었다. 이 모델은 커넥터에서 메소드 호출의 시작과 결과를 관리하여 제어와 계산을 분리한다. 하지만 컴포넌트 사이의 연결 계층과 커넥터 수가 증가 할수록 시스템을 구성하는 객체의 수가 크게 증가하는 문제점을 가지고 있다. 본 논문에서는, 직접 메시지 전달과 간접 메시지 전달이 혼합된 하이브리드 메시지 전달을 사용한 트리 컴포넌트 모델을 제안한다. 이는 컴포넌트를 인터페이스들로 랩핑하여 모든 제어가 계산과 분리되어 인터페이스 레퍼런스를 통해서만 이루어진다. 이렇게 연결된 컴포넌트 사이의 조합은 항상 트리 구조를 이루는 특징이 있다. 아울러 구현 예와 비교 평가를 통해 트리 컴포넌트 모델이 실용적으로 적용 가능하고 시스템의 구성과 메시지 전달을 중재하는 객체 수의 감소를 확인할 수 있었다.

• 한국멀티미디어학회논문지
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• 제13권12호
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• pp.1767-1777
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• 2010

In digital TV broadcasting, such as terrestrial, cable, satellite, and IPTV, the head-end of digital TV broadcasting has a more complicated transmission structure than that of analog TV broadcasting. Furthermore, digital TV broadcasting has a feature that supports multiplex models, such as Multiple Program Transport Stream (MPTS). Therefore, the purpose of our work was to design and examine a more efficient new system of emergency alert message transmission to support the digital TV broadcasting environments. Digital TV broadcasting is the IP generation or RF transmission of 8-VSB, QAM, and QPSK modulated through a multiplexer or re-multiplexer multiplexed stream as a MPEG-2 Transport Stream after content encoding. The new system proposed in this paper transmits an emergency alert message without scrambling after replacing the PID and payload of the -packet with the message prototype in the TS stream from the multiplexer. If we need to transmit an emergency alert message under digital TV broadcasting services, then the receiver first checks the PID of each packet in the TS stream for the emergency alert message. Next, if a packet is determined to be an emergency alert message, then the set-top box displays the message on the TV screen using its function of On Screen Display, or the PC based software displays the message on the monitor screen using its function of overlay with user interface if the packet is found to be an emergency alert message. We have designed an emergency alert message protocol and a system model. By experiments and analysis of the system, we concluded that the system achieved efficiency and the ability to send and receive emergency alert messages using the system under different digital TV broadcasting service environments.

• 한국콘텐츠학회논문지
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• 제8권1호
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• pp.152-159
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• 2008

본 논문에서는 SIP(Session Initiation Protocol) 기반의 인스턴트 메시징 서비스에서 멀티미디어 메시지를 효율적으로 처리할 수 있는 새로운 방법을 연구하였다. 전체 시스템은 멀티미디어 메시지 서버와 프레즌스(presence) 서버 및 사용자 시스템으로 구성되며, 메시지 서버에 저장된 메시지들의 개수, 대기상태, 메시지의 타입 등 각종 정보를 사용자들에게 효율적으로 제공하기 위한 수단으로써 기존의 메시지 대기 표시 이벤트 패키지를 대신하는 새로운 방법을 제시하였다. 제안된 방법에서는 메시지 상태 정보에 변화가 발생하면 이 정보를 프레즌스 서버에게 보내어 프레즌스 정보 통지 시에 별도의 태그로 전송하도록 한다. 프레즌스 서버는 사용자로부터의 등록 요청 및 통지를 처리하며 서비스 사용자들에게 메시지 상태 정보 및 온라인 여부 등 각종 통신 상태 정보를 함께 제공하여 기존 방식에 비해 효율을 높일 수 있도록 하였다. 이때 사용자 시스템과 프레즌스 서버 사이의 데이터 전송 효율을 더욱 높이기 위하여 부분 (partial) publication 기능이 사용되었다. 제안된 방식은 멀티미디어 메시지 전송 속도와 서버의 전체 처리 시간을 측정하는 실험을 통하여 성능을 분석하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(3)
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• pp.209-212
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• 2001

In this paper, an intelligent notification system has been presented. The system operates on both wired and wireless internet. When a new message has been uploaded in a bulletin board systems(BBS) on HTTP web server, it sends the same message to their cellular phones of all members of a given group at the same time via SMS(Short Message Service). In addition, on reading SMS message, those who read them respond to a WAP server using pulling technique via wireless internet. Therefore, the HTTP server does know the members who did not read the message yet. Two different web servers, the HTTP server and the WAP server, running on a single system has been implemented. They share the single database which covers al1 related information about the BBS. The set of experiments shows that the notification system works well as we have expected Thus, we conclude that the proposed system that operates on both wired and wireless internet is the one of successful model for such environments.

• 한국통신학회논문지
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• 제21권10호
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• pp.2605-2619
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• 1996

In this paper, we evaluated performance of mobile exchange control part. Queueing network model is used for modeling of mobile exchange control part. We developed a call control processing and location registration scenartio which has a message exchange function between processors in mobile exchange control part. A network symbol are used the simulation models that are composed of the initialization module, message generation module, message routing module, message processing module, message generation module, HIPC network processing module, output analysis module. as a result of computer simulation, we obtain the processor utilization, the mean queue length, the mean waiting time of control part based on call processing and location registration capacity. The call processing and location registration capacity is referred by thenumber of call attempts in the mobile exchange and must be satisfied with the quality of service(delay time).

• Journal of Information Technology Applications and Management
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• 제23권1호
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• pp.97-117
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• 2016

Drawing on the theoretical framework of customer value-satisfaction-loyalty, this study examines how scarcity message influences customers' value, satisfaction, and loyalty in the context of group-buying social commerce. Previous studies have argued that scarcity message limiting the avilability of products and service is a source of enhancing customer value. In this regard, this study posits scarcity message as a predictor of customer value. Furthermore, this study classifies customer value into two forms (i.e., utilitarian value and hedonic value) and verfies how scarcity message is associated with them. To test the proposed research model and hypotheses, this study performed structural equation modeling (SEM) analyses, using a total of 292 data collected on users who have experience in purchasing products and service through group-buying social commerce sites such as Coupang, Timon, and WeMakePrice. The key results are as follows : First, scarcity message increases utilitarian and hedonic values and further customer satisfaction. Second, utilitarian value increases customer satisfaction and repurchase intention while hedonic value has nothing to do with them. The findings imply that customers seek to maximize utilitarian value through group-buying social commerce. Finally, this study indicates that repuchase intention depends greatly on customer satisfaction.