• Title/Summary/Keyword: Infinite product

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The Study for Performance Analysis of Software Reliability Model using Fault Detection Rate based on Logarithmic and Exponential Type (로그 및 지수형 결함 발생률에 따른 소프트웨어 신뢰성 모형에 관한 신뢰도 성능분석 연구)

  • Kim, Hee-Cheul;Shin, Hyun-Cheul
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.9 no.3
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    • pp.306-311
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    • 2016
  • Software reliability in the software development process is an important issue. Infinite failure NHPP software reliability models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. In this paper, reliability software cost model considering logarithmic and exponential fault detection rate based on observations from the process of software product testing was studied. Adding new fault probability using the Goel-Okumoto model that is widely used in the field of reliability problems presented. When correcting or modifying the software, finite failure non-homogeneous Poisson process model. For analysis of software reliability model considering the time-dependent fault detection rate, the parameters estimation using maximum likelihood estimation of inter-failure time data was made. The logarithmic and exponential fault detection model is also efficient in terms of reliability because it (the coefficient of determination is 80% or more) in the field of the conventional model can be used as an alternative could be confirmed. From this paper, the software developers have to consider life distribution by prior knowledge of the software to identify failure modes which can be able to help.

Recent Research Trends of Supercapacitors for Energy Storage Systems (에너지 저장시스템을 위한 슈퍼커패시터 최신 연구 동향)

  • Son, MyungSuk;Ryu, JunHyung
    • Clean Technology
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    • v.27 no.4
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    • pp.277-290
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    • 2021
  • A supercapacitor, also called an ultracapacitor or an electrochemical capacitor, stores electrochemical energy by the adsorption/desorption of electrolytic ions or a fast and reversible redox reaction at the electrode surface, which is distinct from the chemical reaction of a battery. A supercapacitor features high specific power, high capacitance, almost infinite cyclability (~ 100,000 cycle), short charging time, good stability, low maintenance cost, and fast frequency response. Supercapacitors have been used in electronic devices to meet the requirements of rapid charging/discharging, such as for memory back-up, and uninterruptible power supply (UPS). Also, their use is being extended to transportation and large industry applications that require high power/energy density, such as for electric vehicles and power quality systems of smart grids. In power generation using intermittent power sources such as solar and wind, a supercapacitor is configured in the energy storage system together with a battery to compensate for the relatively slow charging/discharging time of the battery, to contribute to extending the lifecycle of the battery, and to improve the system power quality. This article provides a concise overview of the principles, mechanisms, and classification of energy storage of supercapacitors in accordance with the electrode materials. Also, it provides a review of the status of recent research and patent, product, and market trends in supercapacitor technology. There are many challenges to be solved to meet industrial demands such as for high voltage module technologies, high efficiency charging, safety, performance improvement, and competitive prices.

A Study on the Reordering Works of Heaven and Earth: As Analyzed via the Hegelian Concept of Arbeit (헤겔의 노동(勞動, Arbeit) 개념을 통해 본 천지공사(天地公事) 연구)

  • Kim, Dae-hyeon
    • Journal of the Daesoon Academy of Sciences
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    • v.32
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    • pp.175-199
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    • 2019
  • This paper aims to define Kang Jeungsan's Reordering Works of Heaven and Earth through the Hegelian concept of 'labor (arbeit),' which is the fundamental medium in which humans substantialize their own absoluteness in an existentialist context. The Reordering Works of Heaven and Earth performed by Jeungsan enabled Heaven, Earth, and Humanity to communicate with each other through the harmony of Sangsaeng (Mutual Beneficence). As Hegel found the possibility of freedom and emancipation of human subjects through labor and Jeungsan exercised His will to free and emancipate human beings, comparative thinkers are led to recognize a relationship between His Reordering Works of Heaven and Earth and the Hegelian concept of labor. The key point of this paper centers around articulating the meaning of the precise situation wherein labor occurs for the Supreme Being. Labor is a concept that occurs for real-live humans. Human beings can be said to exist between the ideological world and the natural world, or between Heaven and Earth, and this dichotomy creates a specific product given the interplay of infinitude and finitude that it entails. In other words, labor is not a passive deployment but is instead a subjective development. From the point wherein this labor occurs for the Supreme Being, a paradigm shift towards unity begins throughout the universe. The occurrence of God's labor happens at a time of great transformation. These occurrences of God's labor form the communication among Heaven, Earth and Humanity and form a qualitative equality. In other words, the fact that God is far from the world of ideology and has come into the world of finitude means that God conveys His absoluteness to the world of finitude. Therefore, the work of God on Earth builds the world of Heaven on Earth. This can also be seen as the Sangsaeng of Heaven, Earth and Humanity.