• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권8호
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• pp.4093-4107
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• 2019

Proof of Work (PoW) based blockchains have limitations in throughput, time consumption, and energy efficiency. In these systems, a miner will consume significant time and resources to obtain a reward for contributing to the blockchain. To overcome these limitations, recent research on blockchains are focused on accelerating the speed, scalability, and enhancing the security level. By enhancing specific procedures of blockchain system, the level of data integrity supported by the blockchain can become more robust, and efficient. In this paper, a new blockchain consensus model based on the Bryllite Consensus Protocol (BCP) is proposed to support a hyper-connected massively multiplayer online game (MMOG) ecosystem. The BCP scheme enables users to participate directly in new consensus processes through a Proof of Participation (PoP) algorithm. In this model, the consensus algorithm has a simpler form while maintaining high security level. In addition, because the BCP scheme gives users an equal chance to make a contribution to the blockchain, rewards are distributed in an equal fashion, which motivates user participation. The analysis of the proposed scheme is applied to the Bryllite consortium blockchain system (homed in Hong Kong), which is a new blockchain network developed for international game industries, gamers, and game events.

• 방사성폐기물학회지
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• 제11권2호
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• pp.115-131
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• 2013

미즈나미 지하처분연구시설 프로젝트는 일본원자력연구개발기구가 결정질암 내의 심부 지하 환경에 관해 종합적으로 연구하는 프로젝트이다. 미즈나미 프로젝트는 3개의 중첩되는 단계로 구성된다: 지표기반 조사단계 (단계 1), 건설단계 (단계 2), 운영단계 (단계 3)의 총 20년. 미즈나미 프로젝트의 1단계에서 3단계까지의 전체 목표는 1) 심부지질환경을 조사, 분석, 평가하기 위한 기술 정립, 2) 심부 지하 활용을 위한 일련의 공학적 기술 개발이다. 전체 목표 1을 달성하기 위하여, 1단계 목표를 굴착 전에 지질환경을 모사하고 굴착거동을 예측하는 모든 지표기반 조사결과로부터 지질환경 모델을 구축하는 것으로 설정하였다. 전체 목표 2를 달성하기 위하여, 2단계 목표는 지하시설을 위한 상세 설계 개념과 건설 계획을 수립하는 것으로 설정하였다. 본 논문은 결정질암내 지하수의 수리지화학적 특성을 조사하고 평가하기 위한 지질통합적 방법을 소개한다.

• Structural Engineering and Mechanics
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• 제17권3_4호
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• pp.527-537
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• 2004

Consequence-Based Engineering (CBE) is a new paradigm proposed by the Mid-America Earthquake Center (MAE) to guide evaluation and rehabilitation of building structures and networks in areas of low probability - high consequence earthquakes such as the central region of the U.S. The principal objective of CBE is to minimize consequences by prescribing appropriate intervention procedures for a broad range of structures and systems, in consultation with key decision makers. One possible intervention option for rehabilitating unreinforced masonry (URM) buildings, widely used for essential facilities in Mid-America, is passive energy dissipation (PED). After the CBE process is described, its application in the rehabilitation of vulnerable URM building construction in Mid-America is illustrated through the use of PED devices attached to flexible timber floor diaphragms. It is shown that PED's can be applied to URM buildings in situations where floor diaphragm flexibility can be controlled to reduce both out-of-plane and in-plane wall responses and damage. Reductions as high as 48% in roof displacement and acceleration can be achieved as demonstrated in studies reported below.

• 한국중재학회지:중재연구
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• 제28권1호
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• pp.125-151
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• 2018

Rapid industrial growth based on massive fossil fuel energy consumption has caused serious damages on natural environment and every aspects of human life. As demands for clean and pleasant living circumstance increases, conflicts and disputes around environmental problems have also been widespread. Given the 'environmental rights' is a relatively new legal concept, however, resolving environmental disputes through the traditional legal principles and litigation procedures could be restrictive and, in some sense. inefficient as well as expensive. With efforts to develop new legal principles on environmental disputes, the environmental dispute adjustment system has been introduced as an alternative dispute resolution to the traditional legal dispute procedures. The Korean Environmental Dispute Resolution Commission introduced as the environmental dispute adjustment system has been well established for the past twenty-seven years, given the steadily increasing numbers of applications to the Commission over environmental disputes. However, as most cases are still small in money terms and mainly subject to adjudication, the effectiveness and practical contribution of the Commission in the resolution of environmental disputes have in fact been limited. For the enhancement of the status and roles of the Commission as the prior instrument of the alternative dispute resolution(ADR) in environmental disputes, several suggestions could be considered as follows: First, mediation needs to be more activated than adjudication in order to meet the primary purpose of ADR that resolves environmental disputes according to free will of concerned parties. Second, the scope of mediation could be expanded to the areas including potential environmental damages. Third, the roles and responsibilities of the Environmental Dispute Resolution Commissions at both central and local levels need to be evenly distributed. Fourth, the mechanism and procedures of environmental dispute resolution should be standardized. Fifth, the status of the Environmental Dispute Resolution Commission could be elevated in rank by shifting its current affiliation from the Ministry of Environment to the Office of Prime Minister. Sixth, the organizational structure and human resources of the Commission need to be reinforced. Seventh, the current situation that tends to give priority to litigation procedures when an environment dispute is simultaneously pending in litigation and mediation should be eased and properly adjusted. Eighth, the adoption of mandatory mediation in advance to litigation needs to be discussed. Ninth, the legal authority of the Commission's decisions should be further guaranteed. If above suggestions are thoroughly reviewed and properly adopted, the roles, authority and power of the Environmental Dispute Resolution Commission would be increased in the era when environmental conflicts get widespread, requiring an effective alternative environmental dispute resolution mechanism.

• 응용통계연구
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• 제31권1호
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• pp.139-153
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• 2018

최근 정부의 친환경 정책에 따라 태양광 발전 설비가 지속적으로 증가하고 있다. 태양광 발전량은 에너지원인 태양의 특성상 계절에 따라 하루 중 발전이 이루어지는 시간이 일정하지 않다. 이러한 특성으로 인해 태양광 발전량 예측에서는 연속된 시간간격으로 수집된 자료에 적용할 수 있는 시계열 모형 적용에 어려움이 있다. 본 논문에서 제안하는 방법은 연속된 시간자료를 각 시간대 별로 분리, 재구성하여 24개의 (1시-24시) 일별 자료 형태로 예측에 활용하는 방법이다. 강원도 영암 태양광 발전소의 시간별 발전량 자료를 공공데이터포털에서 수집하여 연구하였다. 기존방법과 제안된 방법의 성능차이를 비교하기 위해 ARIMAX, 신경망(neural network model) 모형을 동일한 모형과 변수를 가지는 환경에서 성능차이를 확인하였다.

• Computers and Concrete
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• 제14권2호
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• pp.193-209
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• 2014

Cyclic test of the columns is of practical relevance to the performance of compression members during an earthquake loading. The strength, ductility and energy absorption capabilities of reinforced concrete (RC) columns subjected to cyclic loading have been estimated by many researchers. These characteristics are not normally inherent in plain concrete but can be achieved by effectively confining columns through transverse reinforcement. An extensive experimental program, in which performance of four RC columns detailed according to provisions of ACI-318-08 was studied in contrast with that of four columns confined by a new proposed technique. This paper presents performance of columns reinforced by standard detailing and cast with 25 and 32 MPa concrete. The experimentally achieved load-displacement hysteresis and backbone curves of two columns are presented. The two approaches which work in conjunction with Response 2000 have been suggested to draw analytical back bone curves of RC columns. The experimental and analytical backbone curves are found in good agreement. This investigation gives a detail insight of the response of RC columns subjected to cyclic loads during their service life. The suggested analytical procedures will be available to the engineers involved in design to appraise the capacity of RC columns.

• 접착 및 계면
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• 제7권4호
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• pp.10-12
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• 2006

The successful use of adhesively bonded parts depends on the defect-free bond of the components. Therefore it is necessary to detect relevant faults and defects in an early state of the production. A 100% test should be pursued, but especially at complicated structures the detection of defects is not easy. Possible testing methods, which show a high potential for the NDT of adhesively bonded parts, are thermography based NDT methods. At present mainly two different procedures of active thermography are being used: Pulse and Lock-In Thermography. With pulse thermography the examined material is warmed up with a short energy pulse (light, eddy current or ultrasonic pulse) and the heat response is recorded after a certain time. The result is an infrared image which indicates material defects in different depths. This paper presents a variety of images showing the capability of Lock-In Thermography to image subsurface defects. Several examples of adhesives joints qualify the ultrasonic Lock-In-Thermography for the in-process quality control for adhesive bonded components.

• 조명전기설비학회논문지
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• 제17권3호
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• pp.1-10
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• 2003

옥외 조명 시스템의 응용으로 두 가지 태양광설비(PV) 조명방식에 저압나트륨 램프(low pressure sodium: LPS)와 무전극 램프(electrodeless lamp)를 부하로 한 조명설비 시스템을 설계·제작·설치하며, 전지 수명을 고려한 감시 목적으로 데이터 수집에 유효한 랩뷰(Labview) 프로그램을 사용하였다. 설치된 PV 시스템에서 태양전지 배열로부터 만들어진 전원 및 그것의 최대 출력에 비교된 에너지 손실을 실험하였고, PV 시스템 개체구성 요소들의 성능을 관찰하였으며, 설치된 PV 조명방식들의 성능을 분석한 후, 태양전지 배열 음량을 줄이는 가능성에 대한 태양광 조명설비 동작특성에 대해 고찰하였다.

• Journal of Power Electronics
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• 제14권4호
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• pp.733-741
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• 2014

The integration of photovoltaic (PV) energy sources into DC grid has gained considerable attention because of its enhanced conversion efficiency with reduced number of power conversion stages. During the integration process, a local control unit is normally included with every power conversion stage of the PV source to accomplish the process of maximum power point tracking. A centralized monitoring and supervisory control unit is required for monitoring, power management, and protection of the entire system. Therefore, we propose a field-programmable gate array (FPGA) based centralized control unit that integrates all local controllers with the centralized monitoring unit. The main focus of this study is on the process of integrating many local control units into a single central unit. In this paper, we present design and optimization procedures for the hardware implementation of FPGA architecture. Furthermore, we propose a transient analysis and control design methodology with consideration of the nonlinear characteristics of the PV source. Hardware experiment results verify the efficiency of the central control unit and controller design.

• International Journal of Computer Science & Network Security
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• 제21권12spc호
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• pp.375-382
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• 2021

The paper introduces a model for evaluating and prioritizing mobile quality attributes and refactoring techniques through the examination of their effectiveness during the mobile application development process. The astonishing evolution of software and hardware has increased the demand for techniques and best practices to overcome the many challenges related to mobile devices, such as those concerning device storage, network bandwidth, and energy consumption. A number of studies have investigated the influence of refactoring, leading to the enhancement of mobile applications and the overcoming of code issues as well as hardware issues. Furthermore, rapid and continuous mobile developments make it necessary for teams to apply effective techniques to produce reliable mobile applications and reduce time to market. Thus, we investigated the influence of various refactoring techniques on mobile applications to understand their effectiveness in terms of quality attributes. First, we extracted the most important mobile refactoring techniques and a set of quality attributes from the literature. Then, mobile application developers from nine mobile application teams were recruited to evaluate and prioritize these quality attributes and refactoring techniques for their projects. A prioritization-based model is examined that integrates the lightweight multi-criteria decision making method, called the best-worst method, with the process of refactoring within mobile applications. The results prove the applicability and suitability of adopting the model for the mobile development process in order to expedite application production while using well-defined procedures to select the best refactoring techniques. Finally, a variety of quality attributes are shown to be influenced by the adoption of various refactoring techniques.