• Title/Summary/Keyword: Evolution Mechanism

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A Survey on Public Web Service Repositories (공공 웹서비스 저장소에 대한 연구조사)

  • Hwang, You-Sub
    • Journal of Intelligence and Information Systems
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    • v.16 no.3
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    • pp.15-35
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    • 2010
  • Web service Technology has been developing rapidly as it provides a flexible application-to-application interaction mechanism. Several ongoing research efforts focus on various aspects of Web service technology, including the modeling, specification, discovery, composition and verification of Web services. The approaches advocated are often conflicting-based as they are differing expectations on the current status of Web services as well as differing models of their future evolution. One way of deciding the relative relevance of the various research directions is to look at their applicability to the currently available Web services. To this end, we conducted a survey on currently publicly available Web service repositories. Our aim is to get an idea of the number, complexity and composability of these Web services and see if this analysis provides useful information about the near-term fruitful research directions.

Systematic studies on the freshwater goby, Rhinogobius species (Percifromes, Gobiidae). II. BEographic distribution and taxonomic status of three color types in the Rhinogobius brunneus complex from South Korea. (밀어속(genus Rhinogobius, Gobiidae) 어류의 계통분류학적 연구II. 한국산 밀어(R. brunneus complex) 3型의 분포 및 분류학적 고찰)

  • 김종범;양서영
    • Animal Systematics, Evolution and Diversity
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    • v.12 no.4
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    • pp.331-347
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    • 1996
  • The geographic distribution and variation for Rhinogobius brunneus were surveyed by means of allozymic and morphological analyses and it was revealed that the Korean populations of R. brunneus comprise three distinct types, Type-A, Type-B, and Type-C, which show considerable differentiation to a degree of interspecific level(Rogers' S(1972): $S_{A-B}$=0.631, $S_{A-C}$=0.628, $S_{B-C}$=0.661). In addition, no evidence of gene flow among the types was found at sympatric area and it is assumed that reproductive isolation is completed. Moreover there is microhabitat segregation according to the distance from river mouth among each types and which segregation was regarded as a factor to facilitate reproductive isolating mechanism. Therefore, based on the evidence presented above, these three types of R. brunneus are considered as typical discrete species.

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Comparative Analysis of Strengthening with Respect to Microstructural Evolution for 0.2 Carbon DP, TRIP, Q&P Steels

  • Jin, Jong-Won;Park, Yeong-Do;Nam, Dae-Geun;Lee, Seung-Bok;Kim, Sung-Il;Kang, Nam-Hyun;Cho, Kyung-Mox
    • Korean Journal of Materials Research
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    • v.19 no.6
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    • pp.293-299
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    • 2009
  • The microstructures and mechanical properties of Dual Phase (DP), Transformation-Induced Plasticity (TRIP), and Quenching & Partitioning (Q&P) steels were investigated in order to define the strengthening mechanism of 0.2 C steel. An intercritical annealing between Ac1 and Ac3 was conducted to produce DP and TRIP steel, followed by quenching the DP and TRIP steel being quenched at to room temperature and by the TRIP steel being austemperingaustempered-air cooling cooled the steel toat room temperature, respectively. The Q&P steel was produced from full austenization, followed by quenching to the temperature between $M_s$ and $M_f$, and then enriching the carbon to stabilize the austenite throughout the heat treatment. For the DP and TRIP steels, as the intercritical annealing temperature increased, the tensile strength increased and the elongation decreased. The strength variation was due to the amount of hard phases, i.e., martensite and bainite, respectively in the DP and TRIP steels. It was also found that the elongation also decreased with the amount of soft ferrite in the DP and TRIP steels and with the amount of the that was retained in the austenite phasein the TRIP steel, respectively for the DP and TRIP steels. For the Q&P steel, as the partitioning time increased, the elongation and the tensile strength increased slightly. This was due to the stabilized austenite that was enriched with carbon, even when the amount of retained austenite decreased as the partitioning time increased from 30 seconds to 100 seconds.

Access Management Using Knowledge Based Multi Factor Authentication In Information Security

  • Iftikhar, Umar;Asrar, Kashif;Waqas, Maria;Ali, Syed Abbas
    • International Journal of Computer Science & Network Security
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    • v.21 no.7
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    • pp.119-124
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    • 2021
  • Today, both sides of modern culture are decisively invaded by digitalization. Authentication is considered to be one of the main components in keeping this process secure. Cyber criminals are working hard in penetrating through the existing network channels to encounter malicious attacks. When it comes to enterprises, the company's information is a major asset. Question here arises is how to protect the vital information. This takes into account various aspects of a society often termed as hyper connected society including online communication, purchases, regulation of access rights and many more. In this research paper, we will discuss about the concepts of MFA and KBA, i.e., Multi-Factor Authentication and Knowledge Based Authentication. The purpose of MFA and KBA its utilization for human.to.everything..interactions, offering easy to be used and secured validation mechanism while having access to the service. In the research, we will also explore the existing yet evolving factor providers (sensors) used for authenticating a user. This is an important tool to protect data from malicious insiders and outsiders. Access Management main goal is to provide authorized users the right to use a service also preventing access to illegal users. Multiple techniques can be implemented to ensure access management. In this paper, we will discuss various techniques to ensure access management suitable for enterprises, primarily focusing/restricting our discussion to multifactor authentication. We will also highlight the role of knowledge-based authentication in multi factor authentication and how it can make enterprises data more secure from Cyber Attack. Lastly, we will also discuss about the future of MFA and KBA.

Microstructure-Strengthening Interrelationship of an Ultrasonically Treated Hypereutectic Al-Si (A390) Alloy

  • Kim, Soo-Bae;Cho, Young-Hee;Jung, Jae-Gil;Yoon, Woon-Ha;Lee, Young-Kook;Lee, Jung-Moo
    • Metals and materials international
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    • v.24 no.6
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    • pp.1376-1385
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    • 2018
  • Ultrasonic melt treatment (UST) was applied to an A390 hypereutectic Al-Si alloy in a temperature range of $750-800^{\circ}C$ and its influence on the solidification structure and the consequent increase in strength was investigated. UST at such a high temperature, which is about $100^{\circ}C$ above the liquidus temperature, had little effect on the grain refinement but enhanced the homogeneity of the microstructure with the uniform distribution of constituent phases (e.g. primary Si, ${\alpha}-Al$ and intermetallics) significantly refined. With the microstructural homogeneity, quantitative analysis confirmed that UST was found to suppress the formation of Cu-bearing phases, i.e., $Q-Al_5Cu_2Mg_8Si_6$, $Al_2Cu$ phases that form in the final stage of solidification while notably increasing the average Cu contents in the matrix from 1.29 to 2.06 wt%. A tensile test exhibits an increase in the yield strength of the as-cast alloy from 185 to 208 MPa, which is mainly associated with the solute increment within the matrix. The important role of UST in the microstructure evolution during solidification is discussed and the mechanism covering the microstructure-strengthening interrelationship of the ultrasonically treated A390 alloy is proposed.

Characterizing nonlinear oscillation behavior of an MRF variable rotational stiffness device

  • Yu, Yang;Li, Yancheng;Li, Jianchun;Gu, Xiaoyu
    • Smart Structures and Systems
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    • v.24 no.3
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    • pp.303-317
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    • 2019
  • Magneto-rheological fluid (MRF) rotatory dampers are normally used for controlling the constant rotation of machines and engines. In this research, such a device is proposed to act as variable stiffness device to alleviate the rotational oscillation existing in the many engineering applications, such as motor. Under such thought, the main purpose of this work is to characterize the nonlinear torque-angular displacement/angular velocity responses of an MRF based variable stiffness device in oscillatory motion. A rotational hysteresis model, consisting of a rotatory spring, a rotatory viscous damping element and an error function-based hysteresis element, is proposed, which is capable of describing the unique dynamical characteristics of this smart device. To estimate the optimal model parameters, a modified whale optimization algorithm (MWOA) is employed on the captured experimental data of torque, angular displacement and angular velocity under various excitation conditions. In MWOA, a nonlinear algorithm parameter updating mechanism is adopted to replace the traditional linear one, enhancing the global search ability initially and the local search ability at the later stage of the algorithm evolution. Additionally, the immune operation is introduced in the whale individual selection, improving the identification accuracy of solution. Finally, the dynamic testing results are used to validate the performance of the proposed model and the effectiveness of the proposed optimization algorithm.

A Review of the Research on E-commerce Ecosystem in China (중국 전자상거래 생태계 동향에 관한 연구)

  • Gao, Lan;Han, Jeong-Soo;Kim, Hyung-Ho
    • Journal of Digital Convergence
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    • v.17 no.8
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    • pp.141-148
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    • 2019
  • Based on the theory of information ecology, this paper conducts a quantitative analysis on the research literature of e-commerce ecosystem in China, and clarifies the research hotspots and development trends, so as to provide reference for subsequent studies. With the key words related literatures collected by CNKI as the data source, and the software CiteSpaceIV is used to draw a visual knowledge map, the distribution of e-commerce ecosystem research papers in China is statistically analyzed by econometric analysis method, and literature research is summarized and evaluated. The research results show that previous studies mainly focus on the concept of e-commerce ecosystem, and there are relatively few research results on the construction and evolution mechanism of e-commerce ecosystem, so the depth and breadth of research should be expanded. Applying the concept of e-commerce ecosystem to solve the problems in cross-border e-commerce will be the future research trend.

MiR-24 Simultaneously Regulates Both Oxytocin and Vasopressin (바소프레신과 옥시토신을 동시에 조절 마이크로RNA, miR-24)

  • Lee, Heon-Jin
    • Journal of Life Science
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    • v.29 no.1
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    • pp.118-122
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    • 2019
  • Oxytocin (Oxt) and vasopressin (Avp) are mainly synthesized in neuronal cells of the hypothalamus and are released from the posterior pituitary. The structure and sequences of Oxt and Avp genes imply that they are closely related and that they are the result of a duplication event during evolution. A previous study suggested that a small regulatory microRNA (miRNA), miR-24, regulated Oxt after binding. However, it is not clear whether this miRNA can modulate Avp simultaneously. The aim of the present study was to investigate putative targeting miRNAs of Avp, including miR-24. Targeted candidate miRNA oligonucleotides were transfected into COS-7 cells to elucidate the binding activity of miRNAs and Avp using dual-luciferase assays. The luciferase assay showed that only miR-24 displayed elevated binding activity with Avp as compared to a control and other candidate miRNAs. Transfection with seed mutants of Avp and miR-24 inhibitors clearly showed that miR-24 can directly bind to the Avp gene. These results provide new insight into the regulatory mechanism of neurohypophysial hormones by a single miRNA.

Protecting Mobile Agent with VPN (VPN을 이용한 이동 에이전트의 보호)

  • 박재경;원유헌
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.11 no.3
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    • pp.3-12
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    • 2001
  • In this course of Internet proliferation, many network-related technologies are examined for possible growth and evolution. The use of Internet-based technologies is private networks has further fuelled the demand for network-based applications. The most promising among the new paradigms is the use of mobile agents. The mobile agent is capable of migrating autonomously form node to node in the network, to perform some computations on behalf of the user. The mobile agent paradigm is attractive alternative to traditional client-server programming for a significant class of network-centric applications. It does however, suffer. from a major drawback namely, the potential for malicious attacks, abuse of resources, pilfering of information, and other security issues. These issues are significantly hampering the acceptance of the mobile-agent paradigm. This paper describes the design of a secure mobile agent gateway 7hat can split and merge the agent code with security policy database on the VPN. This mechanism will promote security in the mobile agent systems.

An OpenAPI based Security Framework for Privacy Protection in Social Network Service Environment (소셜 네트워크 서비스 환경에서 개인정보보호를 위한 OpenAPI기반 보안 프레임워크)

  • Yoon, Yongseok;Kim, Kangseok;Shon, Taeshik
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.22 no.6
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    • pp.1293-1300
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    • 2012
  • With the rapid evolution of mobile devices and the development of wireless networks, users of mobile social network service on smartphone have been increasing. Also the security of personal information as a result of real-time communication and information-sharing are becoming a serious social issue. In this paper, a framework that can be linked with a social network services platform is designed using OpenAPI. In addition, we propose an authentication and detection mechanism to enhance the level of personal information security. The authentication scheme is based on an user ID and password, while the detection scheme analyzes user-designated input patterns to verify in advance whether personal information protection guidelines are met, enhancing the level of personal information security in a social network service environment. The effectiveness and validity of this study were confirmed through performance evaluations at the end.