• Title/Summary/Keyword: Keys

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Verifiable self-certified schemes based on ${\gamma}$th -residuosity problem (고차잉여류 문제에 기반한 검증 가능한 자체인증방식)

  • 이보영
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.9 no.4
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    • pp.61-70
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    • 1999
  • In this paper we propose the verifiable self-certified schemes(key distribution scheme identification scheme digital signature scheme) based on ${\gamma}$th -residuosity which make up for defects of Girault's self-certified schemes allow the authenticity of public keys to be verified during the use of the keys. The security of our schemes is based on the difficulty of ${\gamma}$th -residuosity problem and discrete logarithm problem simultaneously.

A Study on Software algorithm for Processing n-key roll-over at Matrix Keyboard (매트릭스 구성 키보드의 n-키 롤-오버 처리를 위한 소프트웨어 알고리즘에 관한 연구)

  • Jun, Ho-Ik;Lee, Hyun-Chang
    • Journal of Software Assessment and Valuation
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    • v.16 no.1
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    • pp.89-94
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    • 2020
  • In this paper, we propose a software algorithm that can configure n-key roll-over that detects all keys without limitation on the number of pressed keys in the dynamic scanning detection of a keyboard composed of a matrix. The proposed algorithm uses the timer interrupt of the microcontroller for computer keyboard control, so that a constant and accurate detection interval can be obtained, and an accurate debounce time can be provided. In order to confirm the effectiveness of the proposed algorithm, a microcontroller was connected to a toy keyboard constructed in the form of a clavier and experiments were conducted. As a result of the experiment, it was confirmed that detection of all keys was performed accurately regardless of the number of keys pressed.

Evaluation of shear-key misalignment in grouted connections for offshore wind tower under axial loading

  • Seungyeon Lee;Seunghoon Seo;Seungjun Kim;Chulsang Yoo;Goangseup Zi
    • Computers and Concrete
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    • v.33 no.5
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    • pp.509-518
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    • 2024
  • In this study, we investigated the effect of shear-key placement on the performance of grouted connections in offshore wind-turbine structures. Considering the challenges of height control during installation, we designed and analyzed three grouted connection configurations. We compared the crack patterns and strain distribution in the shear keys under axial loading. The results indicate that the misalignment of shear keys significantly influences the ultimate load capacity of grouted connections. Notably, when the shear keys were positioned facing each other, the ultimate load decreased by approximately 15%, accompanied by the propagation of irregular cracks in the upper shear keys. Furthermore, the model with 50% misalignment in the shear-key placement exhibited the highest ultimate strength, indicating a more efficient load resistance than the reference model. This indicates that tensile-load-induced cracking and the formation of compressive struts in opposite directions significantly affect the structural integrity of grouted connections. These results demonstrate the importance of considering buckling effects in the design of grouted connections, particularly given the thin and slender nature of the inner sleeves. This study provides valuable insights into the design and analysis of offshore wind-turbine structures, highlighting the need for refined design formulas that account for shifts in shear-key placement and their structural implications.

Key Pre-distribution using the Quorum System in Wireless Sensor Networks (센서 네트워크에서의 쿼럼 시스템을 이용한 키 사전 분배)

  • Kang Ji-Myung;Lee Sung-Ryeoll;Cho Seong-Ho;Kim Chong-Kwon;Ahn Joung-Chul
    • Journal of KIISE:Information Networking
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    • v.33 no.3
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    • pp.193-200
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    • 2006
  • The security feature is essential in wireless sensor network such as intrusion detection or obstacle observation. Sensor nodes must have shared secret between nodes to support security such as privacy. Many methods which provide key pre-distribution need too many keys or support poor security. To solve this problem, probabilistic key pre-distribution is proposed. This method needs a few keys and use probabilistic method to share keys. However, this method does not guarantee key sharing between nodes, and neighbor nodes nay not communicate each other. It leads to waste of network resource such as inefficient routing, extra routing protocol. In this paper, we propose new key distribution method using quorum system which needs a few keys and guarantee key sharing between nodes. We also propose extension of the method which needs fewer keys and guarantee key sharing when node deployment knowledge is well known.

Diagnostic keys of the overcoming risk factors and achieving predictable esthetics in anterior single implant

  • Choi, Geun-Bae;Yang, Jong-Sook
    • Journal of the Korean Academy of Esthetic Dentistry
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    • v.16 no.2
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    • pp.7-18
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    • 2007
  • There is now an increased demand for harmony between the peri-implant gingiva and adjacent dentition. In the event of a pending loss of a single tooth in the aesthetic zone with healthy periodontium, expectation for optimal gingival and prosthodontic aesthetics are often very high. Unfortunately, bone resorption is common following the removal of an anterior tooth, compromising the gingival tissue levels for the eventual implant restoration. Also, improper implant placement and inadequate osseous-gingival support potentially deleterious aesthetic result. The creation of an esthetic implant restoration with gingival architecture that harmonizes with the adjacent dentitionis formidable challenge. The predictability of the peri-implant esthetic outcome may ultimately be determined by the patient's own presenting anatomy rather than the clinician's ability to manage state-of-the-art procedures. To more accurately predict the peri-implant esthetic outcome before removing a failing tooth, a considering of diagnostic keys is essential. This presentation addresses the useful diagnostic keys that affect the predictability of peri-implant gingival aesthetics and the overcoming of the risk factors in anterior single-tooth replacement; it also describes a surgical and prosthodontic technique in achieving a long term successful esthetic outcome. Proper diagnosis and understanding of the biological and periodontal variables of failing dentition and their response to surgical and prosthodontic procedures are the essence of predictability. Using a smart protocol that alters the periodontium toward less risk and more favorable assessment of the diagnostic keys before implant placement will provide the most predictable esthetic outcome. Simple diagnostic keys suggested this presentation are useful method to evaluate the overcoming of the risk factors in anterior single implant restoration.

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A Secure Authentication Model Using Two Passwords in Client Server Systems (클라이언트 서버 시스템 환경하에서 2개의 패스워드를 사용하는 안전한 인증 모델)

  • Lee, Jae-Woo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.3
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    • pp.1350-1355
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    • 2011
  • It is very important issues to protect many system resources using authorized client authentication in distributed client server systems. So it is not enough to prevent unauthorized opponents from attacking our systems that client authentication is performed using only the client's identifier and password. In this paper, we propose a secure authentication database modeling with two authentication keys such as a client authentication key and a server authentication key. The proposed authentication model can be used making high quality of computer security using two authentication keys during transaction processing. The two authentication keys are created by client and server, and are used in every request transaction without user's extra input. Using the proposed authentication keys, we can detect intrusion during authorized client's transaction processing because we can know intrusion immediately through comparing stored authentication keys in client server systems when hackers attack our network or computer systems.

A Traitor Tracing Using an Efficient Key Renewal in Embedded System (임베디드 시스템에서 효율적인 키 갱신을 적용한 Traitor Tracing)

  • Park, Jong-Hyuk;Lee, Deok-Gyu;Yeo, Sang-Soo;Kim, Tai-Hoon;Lee, Seung;Cho, Seong-Eon
    • Journal of Advanced Navigation Technology
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    • v.12 no.3
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    • pp.245-254
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    • 2008
  • If the broadcast message is sent, first of all, the privileged users will decode the session key by using his or her personal key, which the user got previously. The user willget the digital information through this session key. As shown above, the user will obtain messages or session keys using the keys transmitted from a broadcaster, which process requires effective ways for the broadcaster to generate and distribute keys. In addition, when a user wants to withdraw or sign up, an effective process to renew a key is required. It is also necessary to chase and check users' malicious activities or attacking others. This paper presents a method called Traitor Tracing to solve all these problems. Traitor tracing can check attackers and trace them. It also utilizes a proactive way for each user to have effective renewal cycle to generate keys.

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A Study on Generation Methodology of Crime Prediction Probability Map by using the Markov Chains and Object Interpretation Keys (마코프 체인과 객체 판독키를 적용한 범죄 예측 확률지도 생성 기법 연구)

  • Noe, Chan-Sook;Kim, Dong-Hyun
    • Journal of the Korea Society of Computer and Information
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    • v.17 no.11
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    • pp.107-116
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    • 2012
  • In this paper we propose a method that can generate the risk probability map in the form of raster shape by using Markov Chain methodology applied to the object interpretation keys and quantified risk indexes. These object interpretation keys, which are primarily characteristics that can be identified by the naked eye, are set based on the objects that comprise the spatial information of a certain urban area. Each key is divided into a cell, and then is weighted by its own risk index. These keys in turn are used to generate the unified risk probability map using various levels of crime prediction probability maps. The risk probability map may vary over time and means of applying different sets of object interpretation keys. Therefore, this method can be used to prevent crimes by providing the ways of setting up the best possible police patrol beat as well as the optimal arrangement of surveillance equipments.

A Cluster-based Efficient Key Management Protocol for Wireless Sensor Networks (무선 센서 네트워크를 위한 클러스터 기반의 효율적 키 관리 프로토콜)

  • Jeong, Yoon-Su;Hwang, Yoon-Cheol;Lee, Keon-Myung;Lee, Sang-Ho
    • Journal of KIISE:Information Networking
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    • v.33 no.2
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    • pp.131-138
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    • 2006
  • To achieve security in wireless sensor networks(WSN), it is important to be able to encrypt and authenticate messages sent among sensor nodes. Due to resource constraints, many key agreement schemes used in general networks such as Diffie-Hellman and public-key based schemes are not suitable for wireless sensor networks. The current pre-distribution of secret keys uses q-composite random key and it randomly allocates keys. But there exists high probability not to be public-key among sensor nodes and it is not efficient to find public-key because of the problem for time and energy consumption. To remove problems in pre-distribution of secret keys, we propose a new cryptographic key management protocol, which is based on the clustering scheme but does not depend on probabilistic key. The protocol can increase efficiency to manage keys because, before distributing keys in bootstrap, using public-key shared among nodes can remove processes to send or to receive key among sensors. Also, to find outcompromised nodes safely on network, it selves safety problem by applying a function of lightweight attack-detection mechanism.

Study on Healing Game based on Lazzro's 'Four Keys to Fun' (Lazzro의 '4가지 재미요소' 기반 힐링 게임 특성 분석)

  • Kang, Ho-In;Byun, Hae-Won
    • Journal of Korea Game Society
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    • v.18 no.6
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    • pp.39-48
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    • 2018
  • Recently, some games with physical and mental healing function are released. The healing games tend to make people relax. With the features of simple healing contents, the healing games provide users psychological stability more than strong stimulus. The games don't give users continuous excitement, so the popularity of the games goes down soon. In this paper, we investigate domestic and international healing games on the basis of the platform, such as mobile, console and PC. We analyze the feature of healing games with the four keys to fun(Hard Fun, Easy Fun, Serious Fun, People Fun) suggested by Nicole Lazzro. By this analysis, we find how much of the 4 keys to fun the games include and the correlation between the 4 keys to fun and the popularity of the healing games.