• Title/Summary/Keyword: CDM2

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Transitional Dark Energy - A solution to the H0 tension

  • Keeley, Ryan
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.2
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    • pp.59.2-59.2
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    • 2019
  • In this talk, I will explain the implications of a rapid appearance of dark energy between the redshifts ($z$) of one and two on the expansion rate and growth of perturbations. Using both Gaussian process regression and a parametric model, I show that this is the preferred solution to the current set of low-redshift ($z<3$) distance measurements if $H_0=73~\rm km\,s^{-1}\,Mpc^{-1}$ to within 1\% and the high-redshift expansion history is unchanged from the $\Lambda$CDM inference by the Planck satellite. Dark energy was effectively non-existent around $z=2$, but its density is close to the $\Lambda$CDM model value today, with an equation of state greater than $-1$ at $z<0.5$. If sources of clustering other than matter are negligible, we show that this expansion history leads to slower growth of perturbations at $z<1$, compared to $\Lambda$CDM, that is measurable by upcoming surveys and can alleviate the $\sigma_8$ tension between the Planck CMB temperature and low-redshift probes of the large-scale structure.

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Design of PI/PID Controller by CDM for Speed Control of Two-Inertia Systems

  • Kang, Jin-Shig
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.76.4-76
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    • 2002
  • $\textbullet$ Contents 1 Introduction $\textbullet$ Contents 2 Model of Two-inertia System $\textbullet$ Contents 3 Concept of CDM $\textbullet$ Contents 4 Controller Design $\textbullet$ Contents 5 Experimental Results $\textbullet$ Contents 6 Conclusions

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A Study on Control Scheme for Fairness Improvement of Assuared Forwarding Services in Differentiated Service Network (DiffServ 망에서 AF 서비스의 공평성 향상을 위한 제어 기법)

  • Kim, Byun-gon;Jeong, Dong-su
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2015.05a
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    • pp.649-652
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    • 2015
  • Previous marking policy for the AF service of TCP traffic in the Diffserv network have no sufficient consideration on the effect of RTT and target rate. In this paper, in order to improve fairness Index by the effect RTT difference of TCP traffic, we propose the modified TSW3CDM(Time Sliding Window Three Color Dynamic Marker) based on average transfer rate estimation and the flow state. The proposed algorithm is dynamic marking policy that do allocate band width in proportion to transmission rate. To evaluate the performance of the proposed algorithm, We accomplished a computer simulation using NS-2. From simulation results, the proposed TSW3CDM algorithm improves fairness index by comparison with TSW3CM.

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Performance of the Clean Development Mechanism(CDM) Projects of the Asean Countries (아세안 국가들의 청정개발체제 사업에 대한 성과 분석)

  • Gragasin, Michael A.;Ko, Soon-Chul
    • Journal of Agricultural Extension & Community Development
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    • v.19 no.1
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    • pp.147-178
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    • 2012
  • 청정개발체제(CDM)는 1997년 교토의정서(Kyoto protocol)를 통해 확립된 온실가스 배출과 관련된 선진국과 개도국 간 협력 기제의 하나이다. 청정개발체제는 기본적으로 선진국의 정부 또는 민간조직이 개도국에서 배출감축 프로젝트를 수행하고, CER(Certified Emission Reduction)의 형태로 배출권을 얻는 것을 허용하고, CER을 자국의 배출감축목표 달성을 위해 사용할 수 있도록 하고 있다. 이 연구의 목적은 아세안 국가들의 청정개발 메커니즘의 성취도를 알아보는데 있으며, 자료는 2010년 10월 15일 현재 유엔기후변화기본협약(UNFCCC)에 등록된 254개 청정개발체제 사업을 대상으로 분석하였다. 이 연구의 결과, 전체 254개 사업 중 20%만이 탄소배출권을 받은 것으로 나타났으며, 실제 탄소배출권의 총량은 650만 톤이지만, 이는 전체 사업계획서에 반영된 양의 15%에 불과한 것으로 분석되었다. 또한 아세안 국가의 CDM사업과 관련된 장애 요인으로서는 (1) 사업 등록과 탄소배출권 승인 간 시간 격차가 존재하고, (2) 사업계획과 실제 승인량에 차이가 나타나며, (3) 특히 소규모 사업의 경우 높은 거래 비용 때문에 등록 후 배출승인을 신청하지 않고 있는 것으로 나타나고 있다. 이러한 연구결과는 아세안국가들이 CDM사업을 수행하는 데 있어서 선진국들의 주요 파트너가 되고 있지만, 실제로 사업을 통한 탄소배출량은 제한적일 수 있음을 의미한다. 따라서 일부 아세안 국가에서 교토의정서에 따라 자체적으로 탄소배출감축을 시도하고 있음을 고려할 때, 자체적인 CDM의 성공적인 경영, 수행, 운영을 위해 더 많은 선진국들의 협력과 지원이 주어질 필요가 있다.

Development on the Methodology of CDM Projects in the SF6 Recovery and Recycling of Electrical Equipment (전력설비에서의 SF6 회수 및 재활용 CDM 방법론 개발)

  • Pyo, Jeong-Gwan;Sa, Jae-Hwan;Jeon, Eui-Chan
    • Journal of Climate Change Research
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    • v.2 no.3
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    • pp.143-159
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    • 2011
  • Projects applying the CDM methodology AM0035 of the $SF_6$ Emission Reductions in Electrical Grids should provide direct monitoring of all the key parameters that are related to estimation of baseline and project emissions including detailed explanations of key operating conditions and procedures, and an explanation addressing uncertainty as the result of EB meeting 41. Through this study, recovery ratio during maintenance, purity of $SF_6$ before and after disposal, replacing, loss rate of $SF_6$ before and after reclamation, leakage emission from electricity consumption and fossil fuel combustion, considered conservatively the key parameter of various monitoring. Consequently, confirmed the reduction in the amount of reduction due to the baseline emission decrease, project emission increase.

Real Option Study on Cookstove Offset Project under Emission Allowance Price Uncertainty (배출권 가격 불확실성을 고려한 고효율 쿡스토브 보급사업 실물옵션 연구)

  • Lee, Jaehyung
    • Environmental and Resource Economics Review
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    • v.29 no.2
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    • pp.219-246
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    • 2020
  • From the Phase II (2018~2020) of K-ETS, the offset credit from 'CDM projects that domestic companies and others have carried out in foreign countries' can be used in the K-ETS. As a result, stakeholders in the K-ETS market are actively developing overseas CDM projects, such as the 'high-efficiency cook stove project'. which can secure a large amount of credits while marginal cost is relatively low. This paper develops the investment decision-making model of offset project for the 'high-efficiency cook stove project' using the real option approach. Under the uncertainty of the emission allowance price, the optimal investment threshold (p) is derived and sensitivity analysis is conducted. As a result, in the standard scenario (PoA-S), the optimal investment threshold is 29,054won/ton, which is lower than the stock price (pspot). However, allocation entities are not only economics in the CDM project, but also CDM risk factors such as non-renewable biomass ratio, cook stove replacement ratio, equity ratio with host country, investment period and submission limitation of emission allowance. In addition, offset project developers will be able to derive the optimal investment threshold for each business stage and use it for economic feasibility checks.

Transition-$\omega$CDM 모형을 이용한 SN Ia 자료 분석

  • Park, Jae-Hong
    • The Bulletin of The Korean Astronomical Society
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    • v.35 no.1
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    • pp.73.2-73.2
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    • 2010
  • 암흑에너지는 우주상수만으로 여러 우주론 관측 자료들을 잘 설명하고 있지만, 최근 SN Ia 자료가 축적됨에 따라 암흑에너지의 상태방정식 파라미터 $\omega$가 우주상수에서와 같이 -1인 상수인지, 시간에 따라 변하는지를 알아내기 위한 연구가 진행되고 있다. 본 연구에서는 $\omega$가 시간에 따라 갑자기 변하는(sudden jump) transition-$\omega$CDM 모형을 이용하여 SN Ia 자료를 Markov Chain Monte Carlo(MCMC) 방법을 통해 분석했다. Transition-$\omega$CDM 모형에서는 상수인 $\omega$의 값이 임의의 적색이동에서 변한다고 가정하였다. 분석에 사용된 SN Ia 데이터는 307개의 Union 자료와 90개의 CfA3 SN Ia가 추가된 Constitution 자료이며 개별적으로 분석됐다. 그 결과 transition 시기 전후 $\omega$ 값들의 확률밀도분포를 얻어내었고, 이를 통해 SN Ia의 특성을 조사하였다.

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Target Polynomial Design for Interval Plant Using Lipatov Theorem and CDM (CDM과 리파토프 정리를 이용한 구간 플랜트의 목적다항식 설계)

  • Oh, Hak-Joon;Chung, Tae-Jin;Lee, Jin-Kyu;Chung, Chan-Soo
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.50 no.1
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    • pp.1-7
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    • 2001
  • For a parametric uncertain system, there are many results on stability analysis, but only a few synthesis methods. In this paper, we proposed a new target polynomial decision method for the parametric uncertain system to stabilize the closed loop system with maximal parametric $l_2$ stability margin. To this, we used both Lipatov Theorem and coefficient diagram method(CDM). To show the effectiveness of the proposed method, we designed a robust controller for the inverted pendulum system with parametric uncertainties using fixed order pole assignment(FOPA) method and its performance was compared with that of the ${\mu}$ synthesis methods.

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A Study on Acceptance of CDM/UCR in WCO as e-Customs clearance procedures (WCO의 CDM과 UCR을 수용한 전자통관시스템 발전 방안)

  • Ryu, Geun-Woo;Kim, Young-Chun
    • International Commerce and Information Review
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    • v.9 no.2
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    • pp.327-350
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    • 2007
  • A single window platform must be successfully established by implementing CDM/UCR in WCO and UNeDocs in UN/CEFACT, which is part of the framework of standards for secure and facilitate global trade. Core success factors in single window platform for international trade depend on political innovative capacity, advanced leadership of high ranking officials and departments in charge, effective collaborations between the ministries and offices concerned which are supported by supreme executives, self-controlled coordinations between users, convenience and access availability to users, promotion and marketing, identification on predictive impediments, financial raising and revenue model payable, communication's strategy, valid legal basis etc. To settle a stable ubiquitous e-trade platform, firstly, procedures and practices of customs clearance which different from one another mutually must be standardized globally. Secondly, the international standard electronic data exchanges must be introduced to facilitate and simplify customs clearing procedures by holding administrative informations in common between public institutions. thirdly, cooperative work model must be accepted with enhancing outsourcing business between reference groups (export-import firms and IT service providers).

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A Study for the Voice channel extension method using Code Division Multiplexing (부호분할 다중화 기법을 이용한 음성 회선 확대 방안 연구)

  • 권기형;신용조
    • Journal of the Korea Society of Computer and Information
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    • v.3 no.4
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    • pp.103-109
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    • 1998
  • Domastic telephony transmission networks mainly using El in 2.048Mb㎰ is composed to 30 channels and each channel is assigned to 64Kb㎰ voice coding rate. El method always uses TDM, so it is fixed channels. In this paper, it shows that using CDM enlarge the subscribers and voice channels

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