• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.10a
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• pp.531-534
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• 2010

In this paper, we introduce an efficient energy management using a notion of virtual energy system for shared solar-powered sensor network. Virtual energy system is an abstraction that allows sensor network applications on a node to reserve their own fractions of the shared solar cell and the shared rechargeable battery, hence achieving logically partition of a shared renewable power source with no change in design and implementation. Our results show that our design and implementation are reliable, lightweight and efficient, allowing proper isolation of energy consumption among applications.

• Proceedings of the KIEE Conference
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• 2001.11b
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• pp.340-343
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• 2001

In an electrical network, electrical power are transmitted by a various of protection, isolation and control electric circuit devices. This thesis deals with the protection function between circuit-breakers. The protective coordination concerns the behaviour of two devices placed in series in an electrical network, with a short-circuit downstream circuit-breaker. It has two basic principles: First, discrimination which is an increasing requirement of low voltage electrical distribution systems. Second, which is less well known: cascading, which consists of installing a device, whose breaking capacity is less than the three-phase short-circuit current at its terminals and helped by main circuit-breaker. The important advantage of cascading is to be able to install at a branch circuit-breaker of a lesser performance without endangering the safety of the installation for more economical usage. To determine and guarantee co-ordination between two circuit breakers, it is necessary to carry out a theoretical approach, first, and then confirm the results by means of standard tests. This is illustrated in appendix A of IEC 947-2.

• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.2067-2069
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• 1998

A prototype semiconductor switch for the command resonant charging system has been developed for a line type modulator, which charges parallel pulse forming network(PFN) up to voltage of 5 kV at repetition rates of 60 Hz. A phase controlled power supply provides charging of the 4.7 ${\mu}s$ filter capacitor bank to voltage up to 5 kV. A solid state module of series stack array of sixe matched SCRs(1.6 kV, 50 A) is used as a command charging switch to initiate the resonant charging cycle. Both resistive and RC snubber network are used across each stage of the switch assembly in order to ensure proper voltage division during both steady state and transient condition. A master trigger signal is generated to trigger circuits which are transmitted through pulse transformer to each of the 6 series switch stages. A pulse transformer is required for high voltage trigger or power isolation. This paper will discuss trigger method, protection scheme, circuit simulation, and test result.

• International Journal of Computer Science & Network Security
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• v.21 no.8
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• pp.203-211
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• 2021

The article studies the discourse and a legal uncertainty of the popular and generally understandable concept of cybercrime. The authors reveal the doctrinal approaches to the definition of cybercrime, cyberspace, computer crime. The analysis of international legal acts and legislation of Ukraine in fighting cybercrime is carried out. The conclusion is made about the need to improve national legislation and establish international cooperation to develop the tools for countering cybercrime and minimizing its negative outcomes. The phenomenon of nicknames is studied as a semantic source, which potentially generates a number of threats and troubles - the crisis of traditional anthroponymic culture, identity crisis, hidden sociality, and indefinite institutionalization, incognito style, a range of manifestations of loneliness - from voluntary solitude to traumatic isolation and forced detachment. The core idea is that it is the phenomenon of incognito and hidden name (nickname and other alternatives) that is the motivational stimulus for the fact of information trouble or crime.

• International Journal of Computer Science & Network Security
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• v.22 no.2
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• pp.29-38
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• 2022

The growth of digitalization processes around the world, covering almost all areas of human life, including the Fintech sector. In the field of financial technology, radical changes are taking place with increasing levels of automation, openness and consumer focus. In addition, in the context of the spread of coronavirus infection, quarantine and forced isolation, the role of digital technology is coming to the fore worldwide, including in Ukraine. The purpose of the article is to assess the development of Fintech ecosystem of European countries and outline the strategic parameters of domestic Fintech development. The study concluded that the investment raised for the Fintech industry increases annually and the quality and size of transactions gradually increases. Today, Fintech maintains its position as one of the most attractive markets for venture capitalists and the image of an industry with high potential, especially in the era of open banking. The most attractive markets for investors are mature markets, such as the United States, Germany and the United Kingdom, and the preferred niches for investment - the vertical of payments and lending. Trends in investment activity in terms of investing in financial technologies are studied. Moreover, investors prefer businesses that already have a significant scale or considerable potential to achieve it and become sustainable businesses.

• Nuclear Engineering and Technology
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• v.55 no.3
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• pp.814-826
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• 2023

Sensor faults in nuclear power plant instrumentation have the potential to spread negative effects from wrong signals that can cause an accident misdiagnosis by plant operators. To detect sensor faults and make accurate accident diagnoses, prior studies have developed a supervised learning-based sensor fault detection model and an accident diagnosis model with faulty sensor isolation. Even though the developed neural network models demonstrated satisfactory performance, their diagnosis performance should be reevaluated considering real-time connection. When operating in real-time, the diagnosis model is expected to indiscriminately accept fault data before receiving delayed fault information transferred from the previous fault detection model. The uncertainty of neural networks can also have a significant impact following the sensor fault features. In the present work, a pilot study was conducted to connect two models and observe actual outcomes from a real-time application with an integrated system. While the initial results showed an overall successful diagnosis, some issues were observed. To recover the diagnosis performance degradations, additive logics were applied to minimize the diagnosis failures that were not observed in the previous validations of the separate models. The results of a case study were then analyzed in terms of the real-time diagnosis outputs that plant operators would actually face in an emergency situation.

• Journal of Microbiology
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• v.35 no.4
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• pp.271-276
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• 1997

We isolated phenotypic suppressors of an absB (antibiotics synthesis suppression) strain. In the absB colonies, all four antibiotics including two pigmented antibiotics were blocked so that no pigmentation could be found. We assumed that in the colonies with the wuppressive(or reversive) mutation, both pigmentation would be restored so that the strains with suppressive mutation could be cisually detected. Harvested absB spores were treated with chemical mutagen along with electric shock, and were spread on specially fromulated minimal medium plates. The pigmented colonies were isolated from the unpigmented majorities. In one candidate strain, the restoration and significant overproduction of actinorhodin and undecylprodigiosin were recognized. In three other candidate strains, the overproduction of actinorhodin and restoraion of undecylprodigiosin were observed. The production of the two unpigmented antibiotics (CDA and methylenomycin) were visualized in the tested candidate strains. The strains with wuppressive mutations would be very useful in dlucidating the regulation network of antiviotics synthesis and overproduction of the antibiotics.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.1
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• pp.42-46
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• 2014

A modified network to suppress the nth harmonics in a Wilkinson power divider is presented. The solution has been found by adding transmission lines, whose electrical lengths are determined by using the suppression terms, between two transformers of the traditional design. Experimental results show the second and third harmonics levels achieved are -45.3 and -46.4 dB, respectively, while the performance of the power divider at the fundamental frequency is maintained.

• Journal of the Korean institute of surface engineering
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• v.17 no.2
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• pp.29-40
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• 1984

The structure of rapidly solidified Al-Si-based alloys and its relationship to subsequent anodic film growth in near neutral and acid solutions have been investigated. Solidification of the alloys proceeds via pre-dendritic nuclei, associated with rugosity of the casting surface, from which cellular-type growth, comprised of aluminium-rich material surrounded by silicon-containing material, emanates. Observation of ultramicrotomed sections of the alloys and their anodic films reveals the local oxidation of the silicon-rich phase and its incorporation into the anodic alumina film, formed in near neutral solutions. Such incorporation occurs but resultant isolation of the silicon-rich phase is not possible for anodizing in phosphoric acid, and a three-dimensional network of the oxidized silicon-containing phase, with continuing development of porous anodic alumina, is observed.

• Proceedings of the Korean Information Science Society Conference
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• 2012.06d
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• pp.395-397
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• 2012

네트워크 가상화는 물리적인 네트워크를 논리적으로 분활하여 하나의 물리적인 네트워크를 효율적으로 사용할 수 있다. 이러한 네트워크 가상화를 통해서 물리적인 네트워크 위에 독립적인 다양한 서비스들을 수행할 수 있다. 네트워크 가상화를 지원하기 위해서는 가사화된 네트워크 사이에서 대역폭을 조절하고 분배할 수 있는 기법이 필요하다. 가상화된 네트워크 사이에서 한정된 물리 네트워크의 자원을 분배할수 있어야 하고 가상화된 네트워크에 대역폭을 고립시켜 가상화된 네트워크의 대역폭이 다른 가상화된 네트워크의 대역폭에 영향을 끼칠 수 없어야 한다. 따라서 이 논문은 가상화된 네트워크의 대역폭을 분배하는 우선순위 기반 대역폭 조절 기법을 제안하고 가상화된 네트워크간의 대역폭을 고립시킬 수 있는 기법을 구현한다.