• Title/Summary/Keyword: energy-constraints

Search Result 574, Processing Time 0.019 seconds

Low Power EccEDF Algorithm for Real-Time Operating Systems (실시간 운영체제를 위한 저전력 EccEDF 알고리듬)

  • Lee, Min-Seok;Lee, Cheol-Hoon
    • The Journal of the Korea Contents Association
    • /
    • v.15 no.1
    • /
    • pp.31-43
    • /
    • 2015
  • For battery based real-time embedded systems, high performance to meet their real-time constraints and energy efficiency to extend battery life are both essential. Real-Time Dynamic Voltage Scaling (RT-DVS) has been a key technique to satisfy both requirements. In this paper, we present an efficient RT-DVS algorithm called EccEDF that is designed based on ccEDF. The proposed algorithm can precisely calculate the maximum unused utilization with consideration of the elapsed time while keeping the structural simplicity of ccEDF, which overlooked the time needed to run the task in calculating the available slack. The maximum unused utilization can be calculated by dividing remaining execution time($C_i-cc_i$) by remaining time($P_i-E_i$) on completion of the task and it is proved using Fluid scheduling model. We also show that the algorithm outperforms ccEDF in practical applications which is modelled using a PXA250 and a 0.28V-to-1.2V wide-operating-range IA-32 processor model.

A Study on the Optimal Site Selection by Constraint Mapping and Park Optimization for Offshore Wind Farm in the Southwest Coastal Area (서남해 연안 해상풍력 발전단지 지리적 적합지 선정 및 최적배치에 관한 연구)

  • Jung-Ho, Kim;Geon-Hwa, Ryu;Hong-Chul, Son;Young-Gon, Kim;Chae-Joo, Moon
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.17 no.6
    • /
    • pp.1145-1156
    • /
    • 2022
  • In order to effectively secure site suitability for the development of large-scale offshore wind farms, it is essential to minimize the environmental impact of development and analyze the conflicts of benefit between social, ecological, and economic core values. In addition, a preliminary review of site adequacy must be preceded in order not to collide with other used areas in the marine spatial plan. In addition, it is necessary to conduct local meteorological characteristics analysis including wind resources near Jeollanam-do area before project feasibility study. Therefore, wind resource analysis was performed using the observation data of the meteorological mast installed in Wangdeungnyeo near Anmado, Yeonggwang, and the optimal site was selected after excluding geographical constraints related to the location of the offshore wind farm. In addition, the annual energy production was calculated by deriving the optimal wind farm arrangement results suitable for the local wind resources characteristics based on WindSim SW, and it is intended to be used as basic research data for site discovery and selection of suitable sites for future offshore wind farm projects.

Development of Cotton Farming and Transformation of Rural Area in Sanliurfa Prefecture, Turkey (터키 샹르울파주 목화농업의 전개와 지역사회의 변화)

  • Kang, Sukkyeong
    • Journal of the Korean Geographical Society
    • /
    • v.48 no.1
    • /
    • pp.87-111
    • /
    • 2013
  • Regional disparities between eastern and western regions is the most of serious problem for balanced regional development in Turkey. The Southeastern Anatolia Project (GAP) is being implemented to eliminate these regional development disparities. The work that was initially planned as predominantly for hydraulic energy production to utilize water resources of the Tigris and Euphrates rivers more effectively was later transformed into an integrated multi-sector regional development project. This study noted that this region had very limited cash crop production because of the constraints of semi-arid climate of the southeastern region, however, later, it has changed Turkey's major cotton producing region since Southeastern Anatolia Project carried out. Therefore, this study investigated background, process, and content of the Southeastern Anatolia Project with respect to high cotton productivity in this region and examined the dynamic changes of cotton productivity in this region. In addition, Sanliurfa prefecture is one of the main development axes of the Southeastern Anatolia Project, because government investments are concentrated on this prefecture. Therefore, this study examined the background and process of cotton farming growth in this prefecture. In 2011, Sanliurfa prefecture produced 37.6% of Turkey's total cotton production. This is mainly due to agricultural infrastructure expansion such as land consolidation, irrigation, roads and farm roads. Also, it is one of the main factor that subsidies paid to farmers for cotton cultivation. The introduction of irrigation has dramatically changed the direction of seasonal migration of this area. Prior to irrigation, this area had a serious social issue about out-migration for seasonal labor to other areas. However, the introduction of irrigation made this area that changed to in-migration and intramigration for cotton cultivation. Irrigation water is supplied to farmers through the WUAs (Water User Associations) that handed over irrigation water management, operation from DSI (General Directorate of State of Hydraulic Works). However, the WUAs are under the influence of Ashiret, a traditional feudal social structure. Because of this reason, it does not have an efficient management for farmers. Also, it is one of the reasons that this area does not have autonomous farmer organization.

  • PDF

The completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: measurement of the BAO and growth rate of structure of the emission line galaxy sample from the anisotropic power spectrum between redshift 0.6 and 1.1

  • Arnaud de Mattia;Vanina Ruhlmann-Kleider;Anand Raichoor;Ashley J Ross;Amelie Tamone;Cheng Zhao;Shadab Alam;Santiago Avila;Etienne Burtin;Julian Bautista;Florian Beutler;Jonathan Brinkmann;Joel R Brownstein;Michael J Chapman;Chia-Hsun Chuang;Johan Comparat;Helion du Mas des Bourboux;Kyle S Dawson;Axel de la Macorra;Hector Gil-Marin;Violeta Gonzalez-Perez;Claudio Gorgoni;Jiamin Hou;Hui Kong;Sicheng Lin;Seshadri Nadathur;Jeffrey A Newman;Eva-Maria Mueller;Will J Percival;Mehdi Rezaie;Graziano Rossi;Donald P Schneider;Prabhakar Tiwari;M Vivek;Yuting Wang;Gong-Bo Zhao
    • Monthly Notices of the Royal Astronomical Society
    • /
    • v.501 no.4
    • /
    • pp.5616-5645
    • /
    • 2021
  • We analyse the large-scale clustering in Fourier space of emission line galaxies (ELG) from the Data Release 16 of the Sloan Digital Sky Survey IV extended Baryon Oscillation Spectroscopic Survey. The ELG sample contains 173 736 galaxies covering 1170 deg2 in the redshift range 0.6 eff = 0.845 we measure DV(zeff)/rdrag = 18.33+0.57-0.62, with DV the volume-averaged distance and rdrag the comoving sound horizon at the drag epoch. In combination with the RSD measurement, at zeff = 0.85 we find fσ8(zeff) = 0.289+0.085-0.096, with f the growth rate of structure and σ8 the normalization of the linear power spectrum, DH(zeff)/rdrag = 20.0+2.4-2.2 and DM(zeff)/rdrag = 19.17 ± 0.99 with DH and DM the Hubble and comoving angular distances, respectively. These results are in agreement with those obtained in configuration space, thus allowing a consensus measurement of fσ8(zeff) = 0.315 ± 0.095, DH(zeff)/rdrag = 19.6+2.2-2.1 and DM(zeff)/rdrag = 19.5 ± 1.0. This measurement is consistent with a flat ΛCDM model with Planck parameters.