• Title/Summary/Keyword: power-laws

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An Exploratory Study on Contactless Digital Economy: the Characteristics, Regulatory Issues and Resolutions (비대면 디지털 경제에 대한 탐색적 연구: 특성, 규제쟁점 및 개선방안을 중심으로)

  • Shim, Woohyun;Won, Soh-Yeon;Lee, Jonghan
    • Informatization Policy
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    • v.29 no.2
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    • pp.66-90
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    • 2022
  • The radical digital transformation and development of the contactless digital economy in the wake of the COVID-19 pandemic are increasing the need to solve various problems such as conflicts of interest among market participants and delays in related laws and regulations. This study investigates the concept and characteristics of the contactless digital economy and identifies the related regulatory issues and resolutions through literature review, news article analysis, and expert interviews. From the literature review, it is identified that the contactless digital economy has eight hyper-innovation characteristics: hyper-intelligence, hyper-connectivity, hyper-convergence, hyper-personalization, hyper-automation, hyper-precision, hyper-diversity, and hyper-trust. From news article analyses and expert interviews, this study identifies various regulatory issues, such as competition between incumbents and new entrants, the collision of constitutional rights, collision of social values, conflict between market participants, absence of laws and regulations, and existence of excessive market power, and then proposes a series of resolutions.

The effects of activated cooler power on the transient pressure decay and helium mixing in the PANDA facility

  • Kapulla, R.;Paranjape, S.;Fehlmann, M.;Suter, S.;Doll, U.;Paladino, D.
    • Nuclear Engineering and Technology
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    • v.54 no.6
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    • pp.2311-2320
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    • 2022
  • The main outcomes of the experiments H2P6 performed in the thermal-hydraulics large-scale PANDA facility at PSI in the frame of the OECD/NEA HYMERES-2 project are presented in this article. The experiments of the H2P6 series consists of two PANDA tests characterized by the activation of three (H2P6_1) or one (H2P6_2) cooler(s) in an initially stratified and pressurized containment atmosphere. The initial stratification is defined by a helium-rich region located in the upper part of the vessel and a steam/air atmosphere in the lower part. The activation of the cooler(s) results i) in the condensation of the steam in the vicinity of the cooler(s), ii) the corresponding activation of large scale natural circulation currents in the vessel atmosphere, with the result of iii) the re-distribution and mixing of the Helium stratification initially located in the upper half of the vessel and iv) the continuous pressure decay. The initial helium layer represents hydrogen generated in a postulated severe accident. The main question to be answered by the experiments is whether or not the interaction of the different, localized cooler units would be important for the application of numerical methods. The paper describes the initial and boundary conditions and the experimental results of the H2P6 series with the suggestion of simple scaling laws for both experiments in terms of i) the temperature difference(s) across the cooler(s), ii) the transient steam and helium content and iii) the pressure decay in the vessel. The outcomes of this scaling indicate that the interaction between separate, closely localized units does not play a prominent role for the present experiments. It is therefore reasonable to model several units as one large component with equivalent heat transfer area and total water flow rate.

HMM Based Part of Speech Tagging for Hadith Isnad

  • Abdelkarim Abdelkader
    • International Journal of Computer Science & Network Security
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    • v.23 no.3
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    • pp.151-160
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    • 2023
  • The Hadith is the second source of Islamic jurisprudence after Qur'an. Both sources are indispensable for muslims to practice Islam. All Ahadith are collected and are written. But most books of Hadith contain Ahadith that can be weak or rejected. So, quite a long time, scholars of Hadith have defined laws, rules and principles of Hadith to know the correct Hadith (Sahih) from the fair (Hassen) and weak (Dhaif). Unfortunately, the application of these rules, laws and principles is done manually by the specialists or students until now. The work presented in this paper is part of the automatic treatment of Hadith, and more specifically, it aims to automatically process the chain of narrators (Hadith Isnad) to find its different components and affect for each component its own tag using a statistical method: the Hidden Markov Models (HMM). This method is a power abstraction for times series data and a robust tool for representing probability distributions over sequences of observations. In this paper, we describe an important tool in the Hadith isnad processing: A chunker with HMM. The role of this tool is to decompose the chain of narrators (Isnad) and determine the tag of each part of Isnad (POI). First, we have compiled a tagset containing 13 tags. Then, we have used these tags to manually conceive a corpus of 100 chains of narrators from "Sahih Alboukhari" and we have extracted a lexicon from this corpus. This lexicon is a set of XML documents based on HPSG features and it contains the information of 134 narrators. After that, we have designed and implemented an analyzer based on HMM that permit to assign for each part of Isnad its proper tag and for each narrator its features. The system was tested on 2661 not duplicated Isnad from "Sahih Alboukhari". The obtained result achieved F-scores of 93%.

A Study on the Basic Structure of GIS Industry Promotional Laws (GIS산업진흥법(가칭)의 기본체계 도출에 관한 연구)

  • Lee, Kook-Chul
    • The Journal of the Korea institute of electronic communication sciences
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    • v.3 no.1
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    • pp.46-52
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    • 2008
  • The research which sees will be able to support the growth and an international competitive power improvement of domestic GIS industry institutionally there is a goal industrial promotion Buddhist priest's robe basic system GIS escape. Investigation of the relation literature which is announced first of all from the inside and outside of the country led investigated the present condition, a problem point and developmental prospective etc. of GIS industries.

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Direct Calculation Method for Excited-state Diffusion-influenced Reversible Reactions with an External Field

  • Reigh, Shang Yik;Kim, Hyo-Joon
    • Bulletin of the Korean Chemical Society
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    • v.33 no.3
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    • pp.1015-1019
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    • 2012
  • The direct calculation method is generalized to the excited-state diffusion-influenced reversible reaction of a neutral and a charged particle under an external field with two different lifetimes and quenching in three dimensions. The present method provides an alternative way to calculate the binding probability density functions and the survival probabilities from the corresponding irreversible results. The solutions are obtained as the series solutions by the diagonal approximation due to the anisotropy of the unidirectional external field. The numerical results are found to be in good agreement with those of the previous study [S. Y. Reigh et al. J. Chem. Phys. 132, 164112 (2010)] within a weak field limit. The solutions of two approaches show qualitatively the same overall behavior including the power laws at long times.

Adaptive Current Control Scheme of PM Synchronous Motor with Estimation of Flux Linkage and Stator Resistance

  • Kim, Kyeoug-Hwa;Baik, In-Cheol;Chung, Se-Kyo;Youn, Myung-Joong
    • Proceedings of the KIPE Conference
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    • 1996.06a
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    • pp.17-20
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    • 1996
  • An adaptive current control scheme of a permanent magnet (PM) synchronous motor with the simultaneous estimation of the magnitude of the flux linkage and stator resistance is proposed. The adaptive parameter estimation is achieved by a model reference adaptive system (MRAS) technique. The adaptive laws are derived by the Popov's hyperstability theory and the positivity concept. The predictive control scheme is employed for the current controller with the estimated parameters. The robustness of the proposed current control scheme is compared with the conventional one through the computer simulations.

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Robust Speed Control of Brushless DC Motor Using Adaptive Input-Output Linearization Technique (적응 입출력 선형화 기법을 이용한 Brushless DC Motor의 강인한 속도 제어)

  • 김경화;백인철;문건우;윤명중
    • Proceedings of the KIPE Conference
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    • 1997.07a
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    • pp.89-96
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    • 1997
  • A robust speed control scheme for a brushless DC(BLDC) motor using an adaptive input-output linearization technique is presented. By using this technique, the nonlinear motor model can be linearized in Brunovski canonical form, and the desired speed dynamics can be obtained based on the linearized model. This control technique, however, gives an undesirable output performance under the mismatch of the system parameters and load conditions. For the robust output response, the controller parameters will be estimated by a model reference adaptive technique where the disturbance torque and flux linkage are estimated. The adaptation laws are derived by the Popov's hyperstability theory and positivity concept. The proposed control scheme is implemented on a BLDC motor using the software of DSP TMS320C30 and the effectiveness is verified through the comparative experiments.

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Sensorless Control of PM Synchronous Motor Using Adaptive Observer (적응 관측기를 이용한 영구자석 동기전동기의 센서리스 제어)

  • 홍찬호;윤명중
    • Proceedings of the KIPE Conference
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    • 1997.07a
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    • pp.60-63
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    • 1997
  • A new approach to the position sensor elimination of PM synchronous motor drives is presented in this study. Using the position sensing characteristics of PMSM itself, the actual rotor position as well as the machine speed can be estimated by adaptive flux observer and used as the feedback signal for the vector controlled PMSM drive. The adaptive speed estimation is achieved by model reference adaptive technique. The adaptive laws are derived by the Popov's hyperstability theory and the positivity concept. In order to verify the effectiveness of the proposed scheme, computer simulations are carried out for the actual parameters of a PM synchronous motor and the results well demonstrate that the proposed scheme provides a good estimation value of the rotor speed without mechanical sensor. It is also shown that the actual rotor position as well as the machine speed can be achieved under the variation of the magnet flux linkage. Since the flux linkages are estimated by the adaptive flux observer and used for the identification of the rotor speed, robust estimation of the rotor speed can be performed.

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A Study on V-I Characteristics of Hydrogen-Oxygen Gas Generator

  • Yang Seung-Heun;Kang Byoung-Hee;Gho Jae-Soek;Mok Hyung-Soo;Choe Gyu-Ha
    • Proceedings of the KIPE Conference
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    • 2001.10a
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    • pp.109-112
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    • 2001
  • Water-Electrolyzed gas is a mixed gas of the constant volume ratio 2:1 of Hydrogen and Oxygen gained from electrolyzed water, and it has better characteristics in the field of economy, efficiency of energy, and environmental intimacy than acetylene gas and LPG (Liquefied Petroleum Gas) used for existing gas welding equipment. So studies of Water-Electrolyzed gas are activity in progress nowaday, and commercially used as a source of thermal energy for gas welding in the industry. The object of this paper is getting a V-I characteristic of Hydrogen-Oxygen Gas Generator using DC source. First, chemical analysis of electrolysis is conducted and the relation of electrical energy and then chemical energy is investigated through the faraday's laws.

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Economic Evaluation of Generating Systems Using Renewable Energies (대체에너지 전원개발을 위한 지원방안 및 지원수준 결정)

  • Jo, I.S.;Rhee, C.H.;Jin, B.H.
    • Proceedings of the KIEE Conference
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    • 2000.07a
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    • pp.573-575
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    • 2000
  • For the greenhouse gas emissions' reduction of fossil fuel, the energy policy on promotion of alternative energy should be implemented. Accordingly, national policies on the development and promotion of alternative energy were made and related laws and regulations are being made and comprehensive plans should be followed. The policies and strategies for promoting the renewable energy have been insufficient in comparison with that of the developed countries. This paper suggests the optimal subsidy level for Photovoltaic and Wind Power.

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