• Title/Summary/Keyword: well integrity

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Transactions Ordering based Secure Concurrency Control Scheme (트랜잭션 순서 기반 보안 동시성 제어 기법)

  • Lee Won-Sup;Lee Sang-Hee
    • Journal of the Korea Society of Computer and Information
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    • v.10 no.5 s.37
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    • pp.57-64
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    • 2005
  • While the secure concurrency control schemes in multilevel secure database management systems synchronize transactions cleared at different security level they must consider the problem covert channel. although previous works achieve the confidentiality successfully, they overlook the integrity or the availability. For being evaluated as highly secure database systems , the multilevel secure database management systems must achieve the confidentiality, integrity, and the availability that are the well-known major security aspects. By use of verified transactions ordering relationship, in this Paper, we Propose a new secure concurrency control scheme that is capable of increasing the degree of fairness among transactions cleared at different security levels.

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High speed milling titanium alloy (Ti 합금의 고속가공시 밀링특성에 관한 연구)

  • Ming CHEN;Youngmoon LEE;Seunghan YANG;Seungil CHANG
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2003.04a
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    • pp.454-459
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    • 2003
  • The paper will present chip formation mechanism and surface integrity generation mechanism based on the systematical experimental tests. Some basic factors such as the end milling cutter tooth number, cutting forces, cutting temperature, cutting vibration, the chip status, the surface roughness, the hardness distribution and the metallographic texture of the machined surface layer are involved. the chip formation mechanism is typical thermal plastic shear localization at high cutting speed with less number og shear ribbons and bigger shear angle than at low speed, which means lack of chip deformation. The high cutting speed with much more cutting teeth will be beneficial to the reduction of cutting forces, enlarge machining stability region, depression of temperature increment, auti-fatigability as well as surface roughness. The burrs always exists both at low cutting speed and at high cutting speed. So the deburr process should be arranged for milling titanium alloy in any case.

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The TOR Data Communication System

  • Haraty, Ramzi A.;Zantout, Bassam
    • Journal of Communications and Networks
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    • v.16 no.4
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    • pp.415-420
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    • 2014
  • Since the day the Internet became a common and reliable mechanism for communication and data transfer, security officers and enthusiasts rallied to enforce security standards on data transported over the globe. Whenever a user tries communicating with another recipient on the Internet, vital information is sent over different networks until the information is dropped, intercepted, or normally reaches the recipient. Critical information traversing networks is usually encrypted. In order to conceal the sender's identity, different implementations have proven successful - one of which is the invention of anonymous networks. This paper thoroughly investigates one of the most common and existing techniques used during data communication for avoiding traffic analysis as well as assuring data integrity - the onion router (TOR). The paper also scrupulously presents the benefits and drawbacks of TOR.

Effects of Deaerator in Feedwater System on Steam Generator in Nuclear Power Plant (원자력 발전소 급수계통 탈기기가 증기발생기에 미치는 영향)

  • Choi, Young-Boo;Kim, Si-Moon;Lee, Eun-Woong
    • Proceedings of the KIEE Conference
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    • 1999.07a
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    • pp.403-405
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    • 1999
  • Dissoved oxygen(DO) control by deaerator has a great effect on the integrity of S/G in nuclear power plant. The goal of this study based on the theoretical basis and the extensive surveys is to identify the effect of deaerator in feedwater system on steam generator to clear the need of installation of deaerator. In addition, this paper discusses the review to understand the mechanism of DO formation as well as removal. The conclusion is that the installation of deaerator improve the integrity of S/G and is contributed to the whole nuclear power plant safety.

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A Study on the Relationship between Sound Quality and Structural Mechanics in Automobiles (차량 구조 강성과 소음 음질간의 상관도 연구)

  • Choi Jongdae;Kim Sangmin
    • Proceedings of the Acoustical Society of Korea Conference
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    • autumn
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    • pp.239-242
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    • 2000
  • In the present study, the influence of car body structures to the noise and vibration characteristics has been sought. The numerical modal analysis for the body-in-white is employed to predict the vibratory response of structure, and then followed by the experimental modal testing to confirm the validity of the model. Using the results of numerical simulations with the designated modal parameters, the optimal structural configuration has been deduced. Special interests have been paid to the sensitivity of sound quality to the structural integrity. Since the structural integrity has a close relationship to the structure-born noise, the substantially low frequency range, which is far below the frequency range almost barely sensible by human auditory organ but still quite influential to overall impression, is especially examined. The subjective assessment agrees with the objective evaluation by means of traditional sound measures as well as psychoacoustic metrics.

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Efficient and Secure Group Key Generation Protocol for Small and Medium Business

  • Jung, Hyun Soo
    • Journal of Convergence Society for SMB
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    • v.4 no.4
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    • pp.19-23
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    • 2014
  • Group communication is becoming increasingly popular in Internet applications such as videoconferences, online chatting programs, games, and gambling. For secure communications, the integrity of messages, member authentication, and confidentiality must be provided among group members. To maintain message integrity, all group members use the Group Key (GK) for encrypting and decrypting messages while providing enough security to protect against passive attacks. Tree-based Group Diffie-Hellman (TGDH) is an efficient group key agreement protocol to generate the GK. TGDH assumes all members have an equal computing power. One of the characteristics of distributed computing and grid environments is heterogeneity; the member can be at a workstation, a laptop or even a mobile computer. Member reordering in the TDGH protocol could potentially lead to an improved protocol; such reordering should capture the heterogeneity of the network as well as latency. This research investigates dynamic reordering mechanisms to consider not only the overhead involved but also the scalability of the proposed protocol.

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Improving efficiency of remote data audit for cloud storage

  • Fan, Kuan;Liu, Mingxi;Shi, Wenbo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.4
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    • pp.2198-2222
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    • 2019
  • The cloud storage service becomes a rising trend based on the cloud computing, which promotes the remote data integrity auditing a hot topic. Some research can audit the integrity and correctness of user data and solve the problem of user privacy leakage. However, these schemes cannot use fewer data blocks to achieve better auditing results. In this paper, we figure out that the random sampling used in most auditing schemes is not well apply to the problem of cloud service provider (CSP) deleting the data that users rarely use, and we adopt the probability proportionate to size sampling (PPS) to handle such situation. A new scheme named improving audit efficiency of remote data for cloud storage is designed. The proposed scheme supports the public auditing with fewer data blocks and constrains the server's malicious behavior to extend the auditing cycle. Compared with the relevant schemes, the experimental results show that the proposed scheme is more effective.

Enhanced Security Framework for E-Health Systems using Blockchain

  • Kubendiran, Mohan;Singh, Satyapal;Sangaiah, Arun Kumar
    • Journal of Information Processing Systems
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    • v.15 no.2
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    • pp.239-250
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    • 2019
  • An individual's health data is very sensitive and private. Such data are usually stored on a private or community owned cloud, where access is not restricted to the owners of that cloud. Anyone within the cloud can access this data. This data may not be read only and multiple parties can make to it. Thus, any unauthorized modification of health-related data will lead to incorrect diagnosis and mistreatment. However, we cannot restrict semipublic access to this data. Existing security mechanisms in e-health systems are competent in dealing with the issues associated with these systems but only up to a certain extent. The indigenous technologies need to be complemented with current and future technologies. We have put forward a method to complement such technologies by incorporating the concept of blockchain to ensure the integrity of data as well as its provenance.

A Lattice-Based Role Graph Security Model ensuring Confidentiality and Integrity (비밀성과 무결성을 보장하는 격자개념의 역할그래프 보안 모델)

  • Choi, Eun-Bok
    • Journal of the Korea Society of Computer and Information
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    • v.14 no.6
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    • pp.91-98
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    • 2009
  • In this paper, this model ensures confidentiality and integrity of mandatory access cotrol policy which based on fuzzy function with importance of information. And it solves authorization abuse problem through role graph creation algorithm and flowing policy that security grade is applied. Because this model composes role hierarchy which bind similar role concept to apply to commercial environment, it has expansile advantage by large scale security system as well as is easy that add new role.

The Effect of Military Leader's Behavioral Integrity on the Subordinate's Change-Oriented OCB : Focusing on the Moderating Effect of LMX (군 조직 리더의 언행일치가 구성원의 변화지향적 조직시민행동에 미치는 영향 : LMX의 조절효과를 중심으로)

  • Hax, Sun-Bok
    • Journal of Digital Convergence
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    • v.18 no.5
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    • pp.157-167
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    • 2020
  • This study aims to examine the effect of leader' behavioral integrity on subordinate's change-oriented OCB via their team commitment along with the moderating effect of LMX. For this, 395 soldiers from military organizations where external factors were relatively well controlled besides their personal characteristics were selected and surveyed using hierarchical regression methods. First, the results showed that leader' behavioral integrity was positively related to subordinate's change-oriented OCB. Second, the positive relationship between leader' behavioral integrity and subordinate's change-oriented OCB was mediated by team commitment. Third, the aforementioned mediated relationship was moderated by LMX. Although this study targeted members of military organizations with more restrictions on behavior than private organizations, such as corporations, it could be meaningful in that it confirmed that the leader's behavioral integrity lead to subordinate's voluntary behavior of change-oriented OCB, which should be followed by efforts to make it more general by comparing a variety of public and business organizations.