• Title/Summary/Keyword: Process Scheduling

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Design of AES-Based Encryption Chip for IoT Security (IoT 보안을 위한 AES 기반의 암호화칩 설계)

  • Kang, Min-Sup
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.21 no.1
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    • pp.1-6
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    • 2021
  • The paper proposes the design of AES-based encryption chip for IoT security. ROM based S-Box implementation occurs a number of memory space and some delay problems for its access. In this approach, S-Box is designed by pipeline structure on composite field GF((22)2) to get faster calculation results. In addition, in order to achieve both higher throughput and less delay, shared S-Box are used in each round transformation and the key scheduling process. The proposed AES crypto-processor is described in Veilog-HDL, and Xilinx ISE 14.7 tool is used for logic synthesis by using Xilinx XC6VLX75T FPGA. In order to perform the verification of the crypto-processor, the timing simulator(ModelSim 10.3) is also used.

A New Type of Differential Fault Analysis on DES Algorithm (DES 알고리즘에 대한 새로운 차분오류주입공격 방법)

  • So, Hyun-Dong;Kim, Sung-Kyoung;Hong, Seok-Hie;Kang, Eun-Sook
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.20 no.6
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    • pp.3-13
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    • 2010
  • Differential Fault Analysis (DFA) is widely known for one of the most efficient method analyzing block cipher. In this paper, we propose a new type of DFA on DES (Data Encryption Standard). DFA on DES was first introduced by Biham and Shamir, then Rivain recently introduced DFA on DES middle rounds (9-12 round). However previous attacks on DES can only be applied to the encryption process. Meanwhile, we first propose the DFA on DES key-schedule. In this paper, we proposed a more efficient DFA on DES key schedule with random fault. The proposed DFA method retrieves the key using a more practical fault model and requires fewer faults than the previous DFA on DES.

Analysis of Impact on ERP Customization Module Using CSR Data

  • Yoo, Byung-Keun;Kim, Seung-Hee
    • Journal of Information Processing Systems
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    • v.17 no.3
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    • pp.473-488
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    • 2021
  • The enterprise resource planning (ERP) system is a standardized and advanced business process that many companies are implementing now-a-days through customization. However, it affects the efficiency of operations as these customizations are based on uniqueness. In this study, we analyzed the impact of customized modules and processing time on customer service request (CSR), by utilizing the stacked CSR data during the construction and operation of ERP, focusing on small and medium-sized enterprises (SMEs). As a result, a positive correlation was found between unit companies and the length of ERP implementation; ERP modules and the length of ERP implementation; ERP modules and unit companies; and the type of ERP implementation and ERP module. In terms of CSR, a comparison of CSR processing time of CBO (customized business object) module and STD (standard) module revealed that while the five modules did not display statistically significant differences, one module demonstrated a statistically very significant difference. In sum, the analysis indicates that the CBO-type CSR and its processing cost are higher than those of STD-type CSR. These results indicate that companies planning to implement an ERP system should consider the ERP module and their customization ratio and level. It not only gives the theoretical validity that should be considered as an indicator for decision making when ERP is constructed, but also its implications on the impact of processing time suggesting that the maintenance costs and project scheduling of ERP software must also be considered. This study is the first to present the degree of impact on the operation and maintenance of customized modules based on actual data and can provide a theoretical basis for applying SW change ratio in the cost estimation of ERP system maintenance.

Design of Living Lab with BEMS via EnergyPlus for Scheduling HVAC System Considering Occupancy Schedule (리빙랩(Living-lab) 설계를 위한 BEMS 및 EnergyPlus 기반 재실 여부 고려 공조계획 도출)

  • Lee, Jae-Ho;Kim, Sung-Joong;Yoon, Yong-Tae;Kim, Kyoung-Hoon
    • Journal of the Korean Society of Industry Convergence
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    • v.25 no.6_3
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    • pp.1135-1145
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    • 2022
  • Due to increase in concerns related to the climate change, state-wide promotion of the carbon neutrality has been in progress thus far. Smart City could be one of the measures as the initiative to mitigate the missions process. The primary purpose of Smart City can be summarized to be maximization of the social net-beneift to be returned for the local citizens and derivation of the optimal pattern of the energy consumption could belong to one of the elements included in the net-benefit. Currently, the energy consumption by the buildings has been determined to be responsible for the greatest consumption among the sectors considered to be energy-intensive. Moreover, considering the fact that the consumption by operations of HVAC is responsible for nearly 40% in the commercial buildings, it is virtually not possible to optimize schedules for the energy consumption with considerable deliverables from the perspective of the urban planners. Thus, the methods to implement the optimal schedules for the HVAC commissioned with the OHUs were concluded to be the suitable candidate resources for the simulation by EnergyPlus capable of monitoring the thermal changes in each subject space in the present research.

A Case Study on the Appropriate Construction Personnel of the Typical Floor of Apattment Frame Construction Using the Queueing Model (대기행렬 모형을 활용한 아파트 골조공사 기준층 인적 자원관리 선정사례에 관한 연구)

  • Lee, JeongWon;Kim, BoHee;Ham, NamHyuk;Kim, JaeJun
    • Korean Journal of Construction Engineering and Management
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    • v.23 no.6
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    • pp.3-14
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    • 2022
  • Quantitative analysis of the number of construction workers and construction period can present a new standard for appropriate personnel. This study presents a Queueing model that predicts the execution time of work procedures, the most important factor among work efficiency indicators. During the working cycle of apartment frame construction the same process tends to be repeated the volume of contruction. Based on these characteristics, this study used a Queueing Model and analyzed reference layer cycle of the delayed frame construction. After adjusting the number of people and the construction period, the performance of the model was analyzed and suggested. This study aims to support the decision making of personnel distribution according to the volume of construction by performing a performance analysis of the Queueing Model.

A Simulation-based Genetic Algorithm for a Dispatching Rule in a Flexible Flow Shop with Rework Process (시뮬레이션 기반 유전알고리즘을 이용한 디스패칭 연구: 재작업이 존재하는 유연흐름라인을 대상으로)

  • Gwangheon Lee;Gwanguk Han;Bonggwon Kang;Seonghwan Lee;Soondo Hong
    • The Journal of Bigdata
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    • v.7 no.1
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    • pp.75-87
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    • 2022
  • This study investigates a dynamic flexible flow shop scheduling problem under uncertain rework operations for an automobile pipe production line. We propose a weighted dispatching rule (WDR) based on the multiple dispatching rules to minimize the weighted sum of average flowtime and tardiness. The set of weights in WDR should be carefully determined because it significantly affects the performance measures. We build a discrete-event simulation model and propose a genetic algorithm to optimize the set of weights considering complex and variant operations. The simulation experiments demonstrate that WDR outperforms the baseline dispatching rules in average flowtime and tardiness.

Using the METHONTOLOGY Approach to a Graduation Screen Ontology Development: An Experiential Investigation of the METHONTOLOGY Framework

  • Park, Jin-Soo;Sung, Ki-Moon;Moon, Se-Won
    • Asia pacific journal of information systems
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    • v.20 no.2
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    • pp.125-155
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    • 2010
  • Ontologies have been adopted in various business and scientific communities as a key component of the Semantic Web. Despite the increasing importance of ontologies, ontology developers still perceive construction tasks as a challenge. A clearly defined and well-structured methodology can reduce the time required to develop an ontology and increase the probability of success of a project. However, no reliable knowledge-engineering methodology for ontology development currently exists; every methodology has been tailored toward the development of a particular ontology. In this study, we developed a Graduation Screen Ontology (GSO). The graduation screen domain was chosen for the several reasons. First, the graduation screen process is a complicated task requiring a complex reasoning process. Second, GSO may be reused for other universities because the graduation screen process is similar for most universities. Finally, GSO can be built within a given period because the size of the selected domain is reasonable. No standard ontology development methodology exists; thus, one of the existing ontology development methodologies had to be chosen. The most important considerations for selecting the ontology development methodology of GSO included whether it can be applied to a new domain; whether it covers a broader set of development tasks; and whether it gives sufficient explanation of each development task. We evaluated various ontology development methodologies based on the evaluation framework proposed by G$\acute{o}$mez-P$\acute{e}$rez et al. We concluded that METHONTOLOGY was the most applicable to the building of GSO for this study. METHONTOLOGY was derived from the experience of developing Chemical Ontology at the Polytechnic University of Madrid by Fern$\acute{a}$ndez-L$\acute{o}$pez et al. and is regarded as the most mature ontology development methodology. METHONTOLOGY describes a very detailed approach for building an ontology under a centralized development environment at the conceptual level. This methodology consists of three broad processes, with each process containing specific sub-processes: management (scheduling, control, and quality assurance); development (specification, conceptualization, formalization, implementation, and maintenance); and support process (knowledge acquisition, evaluation, documentation, configuration management, and integration). An ontology development language and ontology development tool for GSO construction also had to be selected. We adopted OWL-DL as the ontology development language. OWL was selected because of its computational quality of consistency in checking and classification, which is crucial in developing coherent and useful ontological models for very complex domains. In addition, Protege-OWL was chosen for an ontology development tool because it is supported by METHONTOLOGY and is widely used because of its platform-independent characteristics. Based on the GSO development experience of the researchers, some issues relating to the METHONTOLOGY, OWL-DL, and Prot$\acute{e}$g$\acute{e}$-OWL were identified. We focused on presenting drawbacks of METHONTOLOGY and discussing how each weakness could be addressed. First, METHONTOLOGY insists that domain experts who do not have ontology construction experience can easily build ontologies. However, it is still difficult for these domain experts to develop a sophisticated ontology, especially if they have insufficient background knowledge related to the ontology. Second, METHONTOLOGY does not include a development stage called the "feasibility study." This pre-development stage helps developers ensure not only that a planned ontology is necessary and sufficiently valuable to begin an ontology building project, but also to determine whether the project will be successful. Third, METHONTOLOGY excludes an explanation on the use and integration of existing ontologies. If an additional stage for considering reuse is introduced, developers might share benefits of reuse. Fourth, METHONTOLOGY fails to address the importance of collaboration. This methodology needs to explain the allocation of specific tasks to different developer groups, and how to combine these tasks once specific given jobs are completed. Fifth, METHONTOLOGY fails to suggest the methods and techniques applied in the conceptualization stage sufficiently. Introducing methods of concept extraction from multiple informal sources or methods of identifying relations may enhance the quality of ontologies. Sixth, METHONTOLOGY does not provide an evaluation process to confirm whether WebODE perfectly transforms a conceptual ontology into a formal ontology. It also does not guarantee whether the outcomes of the conceptualization stage are completely reflected in the implementation stage. Seventh, METHONTOLOGY needs to add criteria for user evaluation of the actual use of the constructed ontology under user environments. Eighth, although METHONTOLOGY allows continual knowledge acquisition while working on the ontology development process, consistent updates can be difficult for developers. Ninth, METHONTOLOGY demands that developers complete various documents during the conceptualization stage; thus, it can be considered a heavy methodology. Adopting an agile methodology will result in reinforcing active communication among developers and reducing the burden of documentation completion. Finally, this study concludes with contributions and practical implications. No previous research has addressed issues related to METHONTOLOGY from empirical experiences; this study is an initial attempt. In addition, several lessons learned from the development experience are discussed. This study also affords some insights for ontology methodology researchers who want to design a more advanced ontology development methodology.

An Analysis on the Perception of Public Librarians about Lifelong Education Tasks: Focus on Incheon Metropolitan City (공공도서관 사서의 평생교육업무에 대한 인식 연구 - 인천지역을 중심으로 -)

  • Kim, NamJi;Cho, Jane
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.27 no.3
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    • pp.51-73
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    • 2016
  • This study analyzes on the perception of public librarians about lifelong education tasks in public library using Mann Whitney U-test, Spearman rank-order correlation coefficient, Multiple regression analysis. At the same time, analysis about re-education needs using Analytic Hierarchy Process is conducted. As result, at first, 87% of respondents feel moderate or difficult about lifelong education tasks, especially on planning task. At second, librarians who have qualification about lifelong educator feel easier (P=0.04) than others, in detail, task about lecturer liaison (P=0.04) and planning (P=0.05). Adding that, the career experience and the job difficulty of librarians has negative relationship (R=-0.217). Especially scheduling (R=-0.33) and progressing (R=-0.22) tasks show statistically meaningful. At third, as the result of Multiple regression analysis, tasks about planning (P=0.04) and library marketing (P=0.05) are selected as meaningful elements which effect overall difficulty of life long education job. As final, 91% of librarian need retraining for life long education function, as result of spearman (R=-0.210), the more librarians feels difficult about life long education jobs, the more they need retraining. Anyway, as the result of priority of retraining subjects through AHP technique, user communication (CU P=0.310), planning (PL P=0.246), library marketing (LM P=0.173) are in weight order. CR ratio shows 0.146 with permissible degree.

Optimal Trajectory Finding and re-optimization of SBR for Nitrogen Removal (연속 회분식 반응기에서 최적 질소 제거를 위한 최적 궤적 찾기와 재최적화)

  • Kim, Young-Whang;Yoo, ChangKyoo;Lee, In-Beum
    • Korean Chemical Engineering Research
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    • v.45 no.1
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    • pp.73-80
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    • 2007
  • This article aims to optimize the nitrogen removal of a sequencing batch reactor (SBR) through the use of the activated sludge model and iterative dynamic programming (IDP). Using a minimum batch time and a maximum nitrogen removal for minimum energy consumption, a performance index is developed on the basis of minimum area criteria for SBR optimization. Choosing area as the performance index makes the optimization problem simpler and a proper weighting in the performance index makes it possible to solve minimum time and energy problem of SBR simultaneously. The optimized results show that the optimal set-point of dissolved oxygen affects both the total batch time and total energy cost. For two different influent loadings, IDP-based SBR optimizations suggest each supervisory control of batch scheduling and set-point trajectory of dissolved oxygen (DO) concentration, and can save 20% of the total energy cost, while meeting the treatment requirements of COD and nitrogen. Moreover, it shows that the re-optimization of IDP within a batch can solve the modelling error problem due to the influent loading changes, or the process faults.

A Study on the Government's R&D Budgeting Evaluation System in Korea (과학기술혁신체제 하에서의 국가연구개발 평가 시스템 개선에 관한 연구 : 연구개발 예산평가 시스템을 중심으로)

  • Bark, Pyeng-Mu;Lee, Ki-Jong
    • Journal of Korea Technology Innovation Society
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    • v.12 no.4
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    • pp.819-839
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    • 2009
  • Proposed increases to the government's R&D budget should be discussed based on merits of meeting efficiency and effectiveness criteria. The evaluation of the national R&D budget and related programs are performed in two areas: a system of R&D budget coordination and allocation, and a system of R&D program performance. This paper mainly focuses on the operational areas of R&D budget evaluation system with a focus on their impact to efficiency and effectiveness. The core view point for a R&D budget evaluation system involves two directions: Firstly, to detail the relationships between the later stage (ex. post) activities such as, program survey, analysis, and program performance evaluation, with the budget evaluation. Secondly, to critically oversee all R&D coordination procedures with a different perspective. Budgeting is generally known as a serial process of policy making, planning and executing. It is highly desirable for the budget to be allocated to, and spent by, specific programs as planned, and that each plan be aligned with a specific policy. As such, a strong relevance between the program structure and budget code system is integral to successful execution. It should be performed using a decision making system which closely examines the link between policy and budget. It is also recommended that systematic relationships be maintained among budget coordination and allocation, performance evaluations of policy and program levels, and program survey and analysis system, and that their operational schedule should be reviewed comprehensively as a one integrated system. The National Science and Technology Council is expected to play a major and practical role as the center of policy planning and should be supported by the objective and unbiased system which covers overall process from policy making to program evaluation. Finally, increased utilization of contents, timely program survey and analysis, and accurate of activity scheduling of budget coordination and allocation, and diligent program performance evaluation all contribute towards a more efficient and effective overall evaluation system.

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