• Title/Summary/Keyword: Computer case

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A Study of Temporary Permission Delegation In Role-Based Access Control Policy (역할-기반 접근 제어 정책에서 일시적 권한 위임에 관한 연구)

  • Na, Sang-Yeob
    • Journal of the Korea Computer Industry Society
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    • v.10 no.1
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    • pp.21-28
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    • 2009
  • Role-Based Access Control Policy has a role hierarchies in which a higher case role can perform permissions of a lower case role. However, it is necessary for a lower case role to perform a higher case role's permission, which is not allowed to a lower case role, basically. In this paper propose a temporary permission delegation method. As the result of a temporary permission delegation, junior roles can perform senior roles' permissions in a dedicated interval.

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Bounding Worst-Case Data Cache Performance by Using Stack Distance

  • Liu, Yu;Zhang, Wei
    • Journal of Computing Science and Engineering
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    • v.3 no.4
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    • pp.195-215
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    • 2009
  • Worst-case execution time (WCET) analysis is critical for hard real-time systems to ensure that different tasks can meet their respective deadlines. While significant progress has been made for WCET analysis of instruction caches, the data cache timing analysis, especially for set-associative data caches, is rather limited. This paper proposes an approach to safely and tightly bounding data cache performance by computing the worst-case stack distance of data cache accesses. Our approach can not only be applied to direct-mapped caches, but also be used for set-associative or even fully-associative caches without increasing the complexity of analysis. Moreover, the proposed approach can statically categorize worst-case data cache misses into cold, conflict, and capacity misses, which can provide useful insights for designers to enhance the worst-case data cache performance. Our evaluation shows that the proposed data cache timing analysis technique can safely and accurately estimate the worst-case data cache performance, and the overestimation as compared to the observed worst-case data cache misses is within 1% on average.

Deep learning based optimal evacuation route guidance system in case of structure fire disaster (딥러닝 기반의 구조물 화재 재난 시 최적 대피로 안내 시스템)

  • Lim, Jae Don;Kim, Jung Jip;Hong, Dueui;Jung, Hoekyung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.23 no.11
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    • pp.1371-1376
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    • 2019
  • In case of fire in a structure, it is difficult to suppress fire because it can not accurately grasp the location of fire in case of fire. In this paper, we propose a system algorithm that can guide the optimal evacuation route in case of deep learning-based (RNN) structure disaster. The present invention provides a service to transmit data detected by sensors to a server in real time by using installed sensor, to transmit and analyze information such as temperature, heat, smoke, toxic gas around the sensor, to identify the safest moving path within a set threshold, to transmit information to LED guide lights and direction indicators in a structure in real time to avoid risk factors. This is because the information of temperature, heat, smoke, and toxic gas in each area of the structure can be grasped, and it is considered that the optimal evacuation route can be guided in case of structure disaster.

Zirconia ceramic fixed dental prosthesis with all-on-4 concept implants for irradiated maxilla: A case report (방사선 조사된 상악골에서 all-on-4 임플란트에 의해 지지되는 지르코니아 고정성 보철물 수복 증례)

  • Choi, Eun-Joo;Cho, Hye-Won
    • The Journal of Korean Academy of Prosthodontics
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    • v.55 no.2
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    • pp.218-224
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    • 2017
  • The implant-supported fixed dental prosthesis in irradiated maxilla needs meticulous treatment planning due to low bone healing capacity. All-on-4 concept implantation can reduce the number of implants to be placed avoiding bone grafting procedure. Conventionally, prefabricated angled abutments for tilted implants have been used. However, in this case, it was replaced with computer-aided design and computer-aided manufacturing (CAD/CAM) abutment. This case report described all-on-4 concept implantation and fabrication of CAD/CAM zirconia fixed dental prostheses using CAD/CAM titanium abutments.

A Case Study of Indiana University's CEL Program for Pre-service School Teachers (예비교사를 위한 정보화 교육 방향 탐색 연구 -미국 인디애나 대학 사례를 중심으로-)

  • Heo, Gyun
    • Journal of Fisheries and Marine Sciences Education
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    • v.20 no.1
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    • pp.107-120
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    • 2008
  • Building a competency of pre-service school teachers is one of the critical factors to decide right direction of k-12 computer & information education. In this context, we can realize of the importance of computer & information curriculum for pre-service school teachers. The purpose of this study is to explore the case of the CEL(Computer Educator License) program in Indiana University and to find the developmental direction of technology education for pre-service school teachers. To achieve the purpose of study, the methods and procedures involved the following steps: The literature reviews of technology education were performed. The analysis framework based on case study method was designed for collecting data. Data were composed of related documents, web resources, and interview resources. And collected data were analyzed. The finding and recommendation of this study were the importance of following factors: (a) technology integration in the curriculum for pre-service school teachers, (b) differentiated management with skill-based technology education, (c) leadership for using and diffusing technology in the school, and (d) connected curriculum with the national standard indicator.

Bounding Worst-Case DRAM Performance on Multicore Processors

  • Ding, Yiqiang;Wu, Lan;Zhang, Wei
    • Journal of Computing Science and Engineering
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    • v.7 no.1
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    • pp.53-66
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    • 2013
  • Bounding the worst-case DRAM performance for a real-time application is a challenging problem that is critical for computing worst-case execution time (WCET), especially for multicore processors, where the DRAM memory is usually shared by all of the cores. Typically, DRAM commands from consecutive DRAM accesses can be pipelined on DRAM devices according to the spatial locality of the data fetched by them. By considering the effect of DRAM command pipelining, we propose a basic approach to bounding the worst-case DRAM performance. An enhanced approach is proposed to reduce the overestimation from the invalid DRAM access sequences by checking the timing order of the co-running applications on a dual-core processor. Compared with the conservative approach, which assumes that no DRAM command pipelining exists, our experimental results show that the basic approach can bound the WCET more tightly, by 15.73% on average. The experimental results also indicate that the enhanced approach can further improve the tightness of WCET by 4.23% on average as compared to the basic approach.

TMUML: A Singular TM Model with UML Use Cases and Classes

  • Al-Fedaghi, Sabah
    • International Journal of Computer Science & Network Security
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    • v.21 no.6
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    • pp.127-136
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    • 2021
  • In the systems and software modeling field, a conceptual model involves modeling with concepts to support development and design. An example of a conceptual model is a description developed using the Unified Modeling Language (UML). UML uses a model multiplicity formulation approach, wherein a number of models are used to represent alternative views. By contrast, a model singularity approach uses only a single integrated model. Each of these styles of modeling has its strengths and weaknesses. This paper introduces a partial solution to the issue of multiplicity vs. singularity in modeling by adopting UML use cases and class models into the conceptual thinging machine (TM) model. To apply use cases, we adopt the observation that a use-case diagram is a description that shows the internal structure of the part of the system represented by the use case in addition to being useful to people outside of the system. Additionally, the UML class diagram is recast in TM representation. Accordingly, we develop a TMUML model that embraces the TM specification of the UML class diagram and the internal structure extracted from the UML use case. TMUML modeling introduces some of the advantages that have made UML a popular modeling language to TM modeling. At the same time, this approach supplies UML with partial model singularity. The paper details experimentation with TMUML using examples from the literature. Our results indicate that mixing UML with other models could be a viable approach.

A 48-month clinical performance of hybrid ceramic fragment restorations manufactured in CAD/CAM in non-carious cervical lesions: case report

  • Michael Willian Favoreto;Gabriel David Cochinski;Eveline Claudia Martini;Thalita de Paris Matos;Matheus Coelho Bandeca;Alessandro Dourado Loguercio
    • Restorative Dentistry and Endodontics
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    • v.49 no.3
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    • pp.32.1-32.12
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    • 2024
  • From the restorative perspective, various methods are available to prevent the progression of non-carious cervical lesions. Direct, semi-direct, and indirect composite resin techniques and indirect ceramic restorations are commonly recommended. In this context, semi-direct and indirect restoration approaches are increasingly favored, particularly as digital dentistry becomes more prevalent. To illustrate this, we present a case report demonstrating the efficacy of hybrid ceramic fragments fabricated using computer-aided design (CAD)/computer-aided manufacturing (CAM) technology and cemented with resin cement in treating non-carious cervical lesions over a 48-month follow-up period. A 24-year-old male patient sought treatment for aesthetic concerns and dentin hypersensitivity in the cervical region of the lower premolar teeth. Clinical examination confirmed the presence of two non-carious cervical lesions in the buccal region of teeth #44 and #45. The treatment plan involved indirect restoration using CAD/CAM-fabricated hybrid ceramic fragments as a restorative material. After 48 months, the hybrid ceramic material exhibited excellent adaptation and durability provided by the CAD/CAM system. This case underscores the effectiveness of hybrid ceramic fragments in restoring non-carious cervical lesions, highlighting their long-term stability and clinical success.

Design of Electromagnetic Force driving Actuator for Molded Case Circuit Breaker (배선용 차단기(MCCB) 구동용 전자석 조작기(EMFA) 설계)

  • Kim, Rae-Eun;Kang, Jong-Ho;Kwak, Sang-Yeop;Jung, Hyun-Kyo
    • Proceedings of the KIEE Conference
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    • 2008.04c
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    • pp.29-31
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    • 2008
  • Recent years have witnessed that the Korean government prompts the 'Power IT' enterprise to combine electric Power industry with information technology (IT). Especially, in a move to shore up the distribution automation system, the necessity for remote control of molded case circuit breaker (MCCB) is getting more and more important. In this paper, we aimed to propose a remote-controlled MCCB of which the driving device is substituted to electrical equipment for mechanical parts. Driving device of MCCB was designed with the Electromagnetic Force driving Actuator (EMFA). Electromagnetic force and dynamic characteristics of the designed EMFA are analyzed using 2-D finite element method (FEM).

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