• 제목/요약/키워드: Formal synthesis

검색결과 38건 처리시간 0.023초

결정 다이어그램의 최적화를 위한 탐색공간 축소 기법 (Search space pruning technique for optimization of decision diagrams)

  • 송문배;동균탁;장훈
    • 한국통신학회논문지
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    • 제23권8호
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    • pp.2113-2119
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    • 1998
  • BOD의 최적화 문제는 논리합성과 형식검증 영역에서 필수적인 것으로 인식되고 있다. 변수 순서화 문제는 BOD의 크기와 형태에 직접적인 영향을 미치므로, 적절한 변수 순서를 구하는 문제는 매우 중요한 문제이다, 본 논문에서 는 점진적 시프팅이라 부르는 새로운 변수 순서화 알고리듬을 소개한다. 제안된 알고리듬은 기존의 시프팅 알고리듬에서의 탐색공간을 절반이하로 줄이며, 성능의 저하없이 계산시간을 크게 감소시킬 수 있다. 더욱이 점진적 시프팅 알고리듬은 시프팅 알고리듬을 비롯한 다른 변수 순서화 알고리듬에 비해 매우 단순하다. 제안된 알고리듬은 많은 벤치마크 회로를 이용한 실험에서 그 효율성이 입증되었다.

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ANALYZING DYNAMIC FAULT TREES DERIVED FROM MODEL-BASED SYSTEM ARCHITECTURES

  • Dehlinger, Josh;Dugan, Joanne Bechta
    • Nuclear Engineering and Technology
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    • 제40권5호
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    • pp.365-374
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    • 2008
  • Dependability-critical systems, such as digital instrumentation and control systems in nuclear power plants, necessitate engineering techniques and tools to provide assurances of their safety and reliability. Determining system reliability at the architectural design phase is important since it may guide design decisions and provide crucial information for trade-off analysis and estimating system cost. Despite this, reliability and system engineering remain separate disciplines and engineering processes by which the dependability analysis results may not represent the designed system. In this article we provide an overview and application of our approach to build architecture-based, dynamic system models for dependability-critical systems and then automatically generate dynamic fault trees (DFT) for comprehensive, tool-supported reliability analysis. Specifically, we use the Architectural Analysis and Design Language (AADL) to model the structural, behavioral and failure aspects of the system in a composite architecture model. From the AADL model, we seek to derive the DFT(s) and use Galileo's automated reliability analyses to estimate system reliability. This approach alleviates the dependability engineering - systems engineering knowledge expertise gap, integrates the dependability and system engineering design and development processes and enables a more formal, automated and consistent DFT construction. We illustrate this work using an example based on a dynamic digital feed-water control system for a nuclear reactor.

Freedom of contract in the digital age and its implementation in modern technologies: theory and practice

  • Davydova, Iryna;Bernaz-Lukavetska, Olena;Tokareva, Vira;Andriienko, Iryna;Tserkovna, Olena
    • International Journal of Computer Science & Network Security
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    • 제21권12spc호
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    • pp.544-548
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    • 2021
  • Scientific and technical development, as well as the emergence of new types of contracts, which do not have their expression in current legislation, force us to explore the issues of contract law to adapt to change. In this context, the principle of freedom of contract is fundamental, which states that each person has the right to enter into a contractual relationship at his discretion. However, such freedom is not absolute, because the freedom of one person should not violate the freedom of another. Together with the conflict of private and public interests, these phenomena are a field for the study of topical issues of theory and application of the principle of freedom of contract in practice. Research methods are philosophical, general scientific, and special scientific methods, in particular, system-structural, formal-legal, hermeneutic; methods of analysis, synthesis, etc. As a result of the research, the main characteristics of the principle of freedom of contract, its role for private law regulation of contract law are given; approaches to understanding the restriction of contract freedom are analyzed; typical examples and means of such restrictions are identified; demonstrated how contract freedom is embodied in the use of IT tools, which types of contracts are most common in the digital environment.

Delimitation of Jurisdiction of Commercial, Civil and Administrative Courts: IT Challenges

  • Baranenko, Dmytro;Stepanova, Tetiana;Pillai, Aneesh V.;Kostruba, Anatolii;Akimenko, Yuliia
    • International Journal of Computer Science & Network Security
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    • 제22권7호
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    • pp.85-90
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    • 2022
  • In modern conditions of the development of public relations, there is a continuous development of technologies. This not only reflects the convenience of service users, and new technology but also contributes to the emergence of new disputes to protect the rights of stakeholders. Therefore, it is urgent to study the distinctions between the jurisdiction of commercial, civil and administrative courts in resolving IT disputes. The work aims to study the peculiarities of delimitation of the jurisdiction of commercial, civil, and administrative courts through the prism of IT measurement. The research methodology consists of such methods as a historical, comparative-legal, formal-logical, empirical, method of analogy, method of synthesis, method of analysis, and systematic method. Examining the specifics of delimiting the jurisdiction of commercial, civil, and administrative courts through the IT dimension, it was concluded that there is a problem in determining the jurisdiction of the court. In addition, the judicial practice on this issue is quite variable, which negatively affects the predictability of technology in resolving potential disputes. In this regard, the criterion models for distinguishing between commercial, administrative, and civil proceedings according to the legal classification of the parties, as well as the nature of the claim are identified. This separation will contribute to a more accurate application of legal norms and methods of application of administrative norms and reduce the number of cases of improper proceedings.

Aero-elastic wind tunnel test of a high lighting pole

  • Luo, Yaozhi;Wang, Yucheng;Xie, Jiming;Yang, Chao;Zheng, Yanfeng
    • Wind and Structures
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    • 제25권1호
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    • pp.1-24
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    • 2017
  • This paper presents a 1:25 multi-freedom aero-elastic model for a high lighting pole at the Zhoushan stadium. To validate the similarity characteristics of the model, a free vibration test was performed before the formal test. Beat phenomenon was found and eliminated by synthesis of vibration in the X and Y directions, and the damping ratio of the model was identified by the free decay method. The dynamic characteristics of the model were examined and compared with the real structure; the similarity results were favorable. From the test results, the major along-wind dynamic response was the first vibration component. The along-wind wind vibration coefficient was calculated by the China code and Eurocode. When the peak factor equaled 3.5, the coefficient calculated by the China code was close to the experimental result while Eurocode had a slight overestimation of the coefficient. The wind vibration coefficient during typhoon flow was analyzed, and a magnification factor was suggested in typhoon-prone areas. By analyzing the power spectrum of the dynamic cross-wind base shear force, it was found that a second-order vortex-excited resonance existed. The cross-wind response in the test was smaller than Eurocode estimation. The aerodynamic damping ratio was calculated by random decrement technique and the results showed that aerodynamic damping ratios were mostly positive at the design wind speed, which means that the wind-induced galloping phenomenon is predicted not to occur at design wind speeds.

20세기 전환기의 '아방가르드' 예술집단의 근대 '보편주의' 사상-표현에 관한 연구 -근대 예술적 자각을 향한 지적 융합, 보편철학의 발전적 전개- (A Study on the Modern 'Universal Philosophy' Idea-Presentation of 'Avant-garde' Art Groups at the Turn of the 20th's Century - On the Progress of the Philosophies, 'Universalism' as a Intellectual Synthesis toward Awakening for Modern Art -)

  • 오장환
    • 건축역사연구
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    • 제17권6호
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    • pp.87-98
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    • 2008
  • The purpose of this study is ultimately subjected to the Orientalism, even though this deals with some positive effects in the realm of art and architecture as the scope of study, because through which the relationship between two different cultures will be discussed. That is to say, this research focused not only on how the presentation of 'avant-garde' visual art, which is explained as formal 'purity' and 'abstraction' as the characteristics of modern arts, could be made in the transition to the 20th's World, but also on what is the role and meaning of Eastern thoughts, which is popular in that time, for the new philosophical background of the artistic revolution. As a result, this study found that a lot of 'avant-garde' architects such as F. L. Wright, M. Mahony in Prairie School and L. Sullivan, D. Burnham, J. Root in Chicago School, and Lauweriks, H. P. Berlage who introduced Wright's works into the Europe, had possessed the 'Universal Philosophy' including Unitarianism, Transcendentalism, Deism, and Theosophy which are all influenced by Oriental religions and thoughts through historic western philosophers, although it is generally well-known that W. Kandinsky and P. Mondrian were belong to that. Furthermore, they gave attention to the Oriental religions and thoughts in that time, eventually made a historical progressive process of unification of thoughts between East and West. In a word, the new universalism was the philosophical background that made the artist's idea and presentation on 'from Being into Becoming'.

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Propylene Oxide를 이용한 졸-겔법에 의한 MO·Fe12O18 (M/Ba, Sr) 나노 분말의 합성과 물리적 특성 (Synthesis and Physical Properties of MO·Fe12O18 (M/Ba and Sr) Nanoparticles Prepared by Sol-Gel Method Using Propylene Oxide)

  • 이수진;최석범;곽형섭;백승욱
    • 공업화학
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    • 제17권4호
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    • pp.420-425
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    • 2006
  • Propylene oxide (PPO)를 gelation agent로 한 졸-겔법으로 입자가 균일하고 자기적 특성이 우수한 $MO{\cdot}Fe_{12}O_{18}$ (M/Ba and Sr)의 구조식을 가지는 M-type hexagonal ferrite를 제조하였다. 본 방법으로 얻은 졸-겔용액은 매우 안정적인 분산상태를 보이며, $Fe^{3+}$의 겔화가 진행되고, 생성된 $Fe_2O_3$의 표면에서 $Ba^{2+}$ 또는 $Sr^{2+}$의 겔화가 진행되는 것으로 설명될 수 있어서, +3가 이하의 금속이라도 +3가 이상의 금속 존재 하에는 겔화가 가능한 것을 확인하였다. 또한, 기존 방법과 비교하여 값싼 원료를 사용하며, 반응 시간도 1 min 이내로 짧아지는 장점이 있다. 본 제조법으로 얻어진 분말은 기왕에 발표된 문헌 값과 비교하면 $150^{\circ}C$ 이상 낮은 열처리 온도에서 최고의 자기적 특성을 나타냈으며, 향상된 자기적 특성을 보였다. Sr-ferrite의 경우 최대포화자화 값 74.4 emu/g, 보자력 값 6198 Oe을, Ba-ferrite의 경우도 최대포화자화 값 68.1 emu/g, 보자력 값 5155 Oe을 보였다. 이들은 기존에 발표된 문헌 값과 비교하면 각각 10%와 5% 이상 증가된 보자력 값을 나타내어, 고밀도 자기기록재료에 적합함을 확인하였다. 제조된 분말은 1차 건조 분말의 경우 3~5 nm의 입자들이 응집된 50 nm 정도의 구형입자가 생성되고, 열처리 후에는 500 nm 정도의 고른 크기를 가진 육각판상형 입자가 생성된다.

과학교과 역량의 다면적 이해와 쟁점의 탐색: 일반 핵심역량과의 관계를 고려하여 (Exploring Multi-faceted Understandings and Issues Regarding Science Subject Matter Competency: Considering the Relationship with General Core Competency)

  • 이경건;박정우;이선경;홍훈기;심한수;신명경
    • 과학교육연구지
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    • 제43권1호
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    • pp.94-118
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    • 2019
  • 본 연구는 역량기반 교육과정 담론의 동향으로부터 과학과 핵심역량의 다면적 이해를 위한 쟁점을 탐색하고, 일반적 핵심역량과 과학 교과역량 간의 관계를 고찰하고자 하였다. 먼저는 행동주의, 인문주의, 그 포괄적 종합을 중심으로 역량기반 교육과정의 이론적 배경을 살펴보았다. 이후 OECD의 역량 관련 프로젝트(DeSeCo; OECD Education 2030), 미국의 차세대 과학 표준(NGSS), 한국의 2015 개정 교육과정을 역량기반 교육과정의 관점에서 검토하였다. 이와 함께 국내외에서 핵심역량 및 교과역량에 관하여 작성된 주요 문헌 15건이 제시하는 105개의 일반역량 및 45개의 과학역량을 정리하고 체계적으로 분석하였다. 연구결과 첫째, 역량의 정의 및 범주화를 위한 쟁점에 관하여, 일관된 체계 내에서 제시되는 역량들이 일종의 포괄성을 지닌다고 할 때, 역량의 적절한 개수의 문제, 역량의 적절한 층위 문제, 개별 역량들이 얼마나 고유하고 독립적이어야 하는가의 문제를 지적하였다. 둘째, 문헌별 역량 요소들의 경향성으로서 역량 항목들이 개인적-미시적 차원, 공동체적-중시적 차원, 사회적-거시적 차원에서 다양하게 제시됨을 확인하였으며, 일반역량과 교과역량 모두에서 중시적 차원이 강조되고 있음을 밝혔다. 셋째, 일반역량과 교과역량간 관계에 있어서 일반역량은 거시적 차원을 강조하고 교과역량은 미시적 차원을 강조하는 경향에서 간극이 발생함을 밝힘으로써, 양자가 서로 맞닿을 수 있는 부분은 중시적 차원이라는 점에 주목하였다. 이러한 논의는 2015 개정 교육과정을 비롯한 국가교육과정에서의 역량 이해 및 추후 개발을 위하여 적지 않은 통찰을 제공할 것으로 생각된다.