• Journal of the Korea Institute of Information Security & Cryptology
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• v.13 no.2
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• pp.3-11
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• 2003

Proxy signatures are signature schemes in which an original signer delegates her signing capability to a proxy entity, who signs a message on behalf of the original signer. In this paper we propose the ID-based proxy signature schemes using a bilinear map. In the previous R-based proxy signature scheme, the proxy signer can misuse the right of the signing capacity and the public key directory is required. However, by inserting the warrant information such as the identity of the proxy signer and the limit of the signing capacity to the proxy signature, our scheme can prevent the misuse of the proxy key pair by the proxy signer and does not require a public key certificate. Furthermore, our scheme dose not need a secure channel to deliver the warrant. Consequently, the proposed scheme is more efficient and useful than the previous proxy signature schemes.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.2
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• pp.111-116
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• 2019

New technologies such as the IoT, Big Data, and Artificial Intelligence, starting from the Web, mobile, and smart device, enable new business models that did not exist before, and various types of Internet companies based on these business models has been emerged. In this research, we examine the factors that influence the success and failure of Internet companies. To do this, we review the recent studies on business model and examine the variables affecting the success of Internet companies in terms of network effect, user interface, cooperation with actors, creating value for users. Using the five derived variables, we will select 14 Internet companies that succeeded and failed in seven commercial business model categories. We derive decision tree by applying inductive learning based on ID3 algorithm to the analysis result and derive rules that affect success and failure based on derived decision tree. With these rules, we want to present the strategic implications for actors to succeed in Internet companies.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.8 no.3
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• pp.27-37
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• 1998

Chaum과 Heyst가 그룹 소속원에 대한 익명성을 보장하는 그룹 서명 방식을 처음 제안한 이래 많은 종류의 그룹 서명 방식이 제안되었다. 그러나, 제안된 방식들의 대부분은 이산 대수에 근거한 EIGvamal 형태의 디지털 서명 방식에 근거하고 있다. Ohta-Okamoto방식과 Guillou-Quisquater방식과 같은 ID-based 서명 방식에 근거한 그룹 서명 방식이 최근 제안되었으나$^{[11]}$ , Mao는 제안된 방식이 그룹 방법을 피할 수 있는 방법을 제안하고 제안 방식의 안전성을 분석하였다. 본 논문에서 제안하는 방식은 기 제안된 방식과 마찬가지로 Stadler의 검증 가능 암호 기법(verifiable encryption) 과 Schoenmakers 프로토콜을 사용한다.

• CDE review
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• v.10 no.2
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• pp.28-33
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• 2004

1992년 id Software가 최초의 3차원 게임인 Wolfenstein 3D(그림 1)를 선보인 이래, 3차원 게임은 게임 시장에서 주류의 자리를 차지하게 되었다. 저사양의 하드웨어에서 구동되는 모바일 게임을 제외하고는 현재 대부분의 게임이 3차원으로 제작된다고 보아도 무방할 것이다. 이 같은 시장 수요에 부응하여 다수의 3차원 렌더링 엔진이 개발되었는데, 대표적인 것으로는 id Software의 Doom Ⅲ, Criterion의 Renderware, Epic Games의 Unreal Ⅱ 및 Ⅲ, Intrinsic의 Alchemy, NDL의 GameBryo 등이 있다. (중략)

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.25 no.4
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• pp.330-336
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• 1999

Study of dentofacial structure relationships relative to TMJ internal derangement is required to increase the predictability of TMJ internal derangement. But few studies have been reported. The purpose of this study is to reveal any correlation of dentofacial characteristics with TMJ internal derangement by lateral cephalometric analysis. Patients were devided into two groups. (1) Symptomatic patients with TMJ internal derangement (2) Asymptomatic volunteers with no TMJ internal derangement. Twenty symptomatic patients with TMJ internal derangement(7male, 13female) were selected from our clinic and had undergone a standarized clinical examination, panorama, transcranical view, TMJ tomography. Twenty asymptomatic volunteers(9male, 11female) were selected from our clinic with no pain, no limitation of motion. All subjects had undergone lateral cephalometric analysis. The results were obtained as follows. 1. No significant difference between ID and normal group is detected in cranial base. 2. Maxilla position of ID group is located more posterioly than normal group. 3. Mandible position of ID group is located more posteriorly than normal group and facial profile is hyperdivergent. 4. Posterior facial height of ID group is less than normal group thus facial profile is hyperdivergent. The patients, as mentioned, have a high prevalance of ID thus it should be careful in TMJ ID diagnosis and treatment.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.2C
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• pp.348-353
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• 2004

Development of an efficient and secure payment system is prerequisite for the construction of electronic payment mechanism in mobile environment. Since current PayWord protocol system generates vendor's certificate for each transaction, it requires lot of operation for transaction. In this paper, we use a session key generated by ID-based tripartite Key agreement protocol which use an Elliptic Curve Cryptosystem over finite field $F_{q}$ for transactions. Therefore, our protocol reduces algorithm operations. In particular, proposed protocol using ID-based public key cryptosystem has the advantages over the existing systems in speed and it is more secure in Man-in-the-middle attacks and Forward secrecy.

• Journal of radiological science and technology
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• v.38 no.3
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• pp.229-235
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• 2015

Mammoplasty is currently increasing not only for cosmetic surgery, but as well as for the recovery after breast cancer surgery. The prostheses inserted into the breasts of women who have undergone mammoplasty, hide the breast substances and it is becoming increasingly difficult to diagnose breast disease, and fear is growing by the concern of the prostheses bursting by the strap. So we want to develop a strap applicable to women with prostheses inserted, to determine the usefulness, and we also want to compare the utility by comparing the total area of the Inner and Outer parts of the breast and Posterior Nipple Line (PNL), after obtaining video by applying the existing strap and the developed strap to phantom of the prostheses inserted patient shape. When the pressure by the developed pressure, the total area increased by 10.09% from CC view to $9,813.797mm^2$, 3.88% from CC-ID view to $7,621.531mm^2$, PNL increased by 3.41% from CC view to $90.916mm^2$, 1.64% from CC-ID view to$75.357mm^2$. And the breast tissue of the thorax side increased 3.53% from CC view to $177.725mm^2$, and 6.57% from CC-ID view to $152.510mm^2$, and we could verify that the prostheses were completely eliminated in the CC-ID images of developed strap, compared with the existing strap.

• Journal of Microbiology and Biotechnology
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• v.23 no.7
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• pp.905-912
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• 2013

A novel species, Metschnikowia cibodasensis, is proposed to accommodate eight strains (ID03-$0093^T$, ID03-0094, ID03-0095, ID03-0096, ID03-0097, ID03-0098, ID03-0099, and ID03-0109) isolated from flowers of Saurauia pendula, Berberis nepalensis, and Brunfelsia americana in Cibodas Botanical Garden, West Java, Indonesia. The type strain of M. cibodasensis is ID03-$0093^T$ (= NBRC $101693^T$ =UICC $Y-335^T$ = BTCC-$Y25^T$). The common features of M. cibodasensis are a spherical to ellipsoidopedunculate shaped ascus, which contains one or two needle-shaped ascospores, and lyse at maturity. Asci generally develop directly from vegetative cells but sometimes from chlamydospores. The neighbor-joining tree based on the D1/D2 domain of nuclear large subunit (nLSU) ribosomal DNA sequences strongly supports that M. cibodasensis (eight strains) and its closest teleomorphic species, M. reukaufii, are different species by a 100% bootstrap value. The type strain of M. cibodasensis, ID03-$0093^T$, differed from M. reukaufii NBRC $1679^T$ by six nt (five substitutions and one deletion) in their D1/D2 region of nLSU rDNA, and by 18 nt (five deletions, four insertions, and nine substitutions) in their internal transcribed spacer regions of rDNA, respectively. Four strains representative of M. cibodasensis (ID03-$0093^T$, ID03-0095, ID03-0096, and ID03-0099) showed a mol% G+C content of $44.05{\pm}0.25%$, whereas that of M. reukaufii NBRC $1679^T$ was 41.3%. The low value of DNA-DNA homology (5-16%) in four strains of M. cibodasensis and M. reukaufii NBRC $1679^T$ strongly supported that these strains represent a distinct species.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.7
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• pp.445-453
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• 2012

An investigation for removal of 1-indanone (1-ID), which were commonly produced from the biological and/or chemical treatment and natural weathering of the PAHs-contaminated soils, via oxidative transformation mediated by birnessite in the presence of various phenolic mediators is described. This study also examines the potential effect of the natural occurring substance humic acid (HA) on the oxidative transformation. The experiment was carried out in aqueous phase as a batch test (10 mg/L 1-ID, 0.3 mM phenolic mediators, $1.0g/L\;{\delta}-MnO_2$, at pH 5). All of the 11 tested phenoilic mediators belong to the group of natural occurring phenols and are widely used as model constituents of humic substances. From the results of HPLC analysis, it is demonstrated that 1-ID was not reactive to birnessite itself, but it can be effectively removed in birnessite-mediated cross coupling reactions in the presence of the phenolic mediators. The percent removals of 1-ID after 2 day incubation were ranged from 9.2 to 71.2% depending on the phenolic mediators applied. The initial rate constant ($K_{int}$, $hr^{-1}$) values for the 1-ID removals obtained from the pseudo-first-order kinetic plots also widely ranged from 0.18 to 15.0. Results of the correlative analysis between the removal efficiencies and structural characteristics of phenolic mediators indicate that the transformation of the 1-ID was considerably enhanced by the addition of electron-donating substituents (e.g., -OH, $-OCH_3$) at the benzne ring, and much less enhanced by the addition of electron-withdrawing substituents (e.g., -COOH, -CHO). The presence of HA showed that removal efficiencies of 1-ID in the birnessite-phenolic mediator systems decreased with increasing HA concentrations. However at low concentration of HA (< 2 mg/L), it caused some enhancement in the removals of 1-ID as compared to the control.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11a
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• pp.949-951
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• 2005

ID기반의 암호 시스템은 사용자의 ID를 공개키처럼 활용하는 시스템[1]이다. ID 기반 threshold 대리 서명(IDTPS)은 이러한 환경에서 사용 가능한 threshold 대리 서명 기법이며, Xu 등[2]에 의해 SOK-IBS[3]를 기반으로 처음 만들어졌다. 본 논문에서는 Cha-Cheon[4]의 서명 기법을 기반으로 하는 효율적인 ID 기반의 threshold 대리 서명을 제안한다. 여기서는 pairing 연산을 적게 사용하고 pairing에 사용되는 군으로 사상되는 해쉬 함수를 적게 사용하기 때문에 이전 기법보다 효율적이면서도 충분한 안전성을 보장하게 된다.