• 제목/요약/키워드: The present

검색결과 86,916건 처리시간 0.086초

Assessment of electricity demand at domestic level in Balochistan, Pakistan

  • Urooj, Rabail;Ahmad, Sheikh Saeed
    • Advances in Energy Research
    • /
    • 제5권1호
    • /
    • pp.57-64
    • /
    • 2017
  • Electricity is basic need for country development. But at the present time proper planning and policy is require at high pace for power generation network extension due to the increasing population growth rate. Present study aimed to analyze the present and future demand for electricity at household level in Province of Balochistan of Pakistan via simulation modeling. Data of year 2004-2005 was used as baseline data for electricity consumption to predict future demand of electricity at both rural and urban domestic level up to subsequent 30 years, with help of LEAP software. Basically three scenarios were created to run software. One scenario was Business-As-Usual and other two were green scenarios i.e., solar and wind energy scenarios. Results predicted that by using alternative energy sources, demand for electricity will be fulfill and will also reduce burden on non-renewable energy sources due to the greater potential for solar and wind energy present in Balochistan.

Meshless Local Petrov-Galerkin (MLPG) method for dynamic analysis of non-symmetric nanocomposite cylindrical shell

  • Ferezghi, Yaser Sadeghi;Sohrabi, Mohamadreza;Nezhad, Seyed Mojtaba Mosavi
    • Structural Engineering and Mechanics
    • /
    • 제74권5호
    • /
    • pp.679-698
    • /
    • 2020
  • In this paper, the meshless local Petrov-Galerkin (MLPG) method is developed for dynamic analysis of non-symmetric nanocomposite cylindrical shell equations of elastic wave motion with nonlinear grading patterns under shock loading. The mechanical properties of the nanocomposite cylinder are obtained based on a micro-mechanical model. In this study, four kinds of grading patterns are assumed for carbon nanotube mechanical properties. The displacements can be approximated using shape function so, the multiquadrics (MQ) Radial Basis Functions (RBF) are used as the shape function. In order to discretize the derived equations in time domains, the Newmark time approximation scheme with suitable time step is used. To demonstrate the accuracy of the present method for dynamic analysis, at the first a problem verifies with analytical solution and then the present method compares with the finite element method (FEM), finally, the present method verifies by using the element free Galerkin (EFG) method. The comparison shows the high capacity and accuracy of the present method in the dynamic analysis of cylindrical shells. The capability of the present method to dynamic analysis of non-symmetric nanocomposite cylindrical shell is demonstrated by dynamic analysis of the cylinder with different kinds of grading patterns and angle of nanocomposite reinforcements. The present method shows high accuracy, efficiency and capability to dynamic analysis of non-symmetric nanocomposite cylindrical shell, which it furnishes a ground for a more flexible design.

ANALYSIS AND COMPUTATIONS OF OPTIMAL AND FEEDBACK CONTROL PROBLEMS FOR NAVIER-STOKES EQUATIONS

  • Lee, Hyung-Chun
    • 대한수학회지
    • /
    • 제34권4호
    • /
    • pp.841-857
    • /
    • 1997
  • We present analysis and some computational methods for boundary optimal and feedback control problems for Navier-Stokes equations. We use one example to illustrate our methodology and ideas which are applicable to general control problems for Navier-Stokes equations. First, we discuss the existence of optimal solutions and derive an optimality system of equations from which an optimal solution may be computed. Then we present a gradient type iterative method. Finally, we present some numerical results.

  • PDF

임도 시설에 대한 관리자 집단의 의식성향 분석(I) - 임도 활용의 문제점 및 개선방법을 중심으로 - (Preference analysis of administrator group for public forest road use (I) - Problems of forest road use and standards and suggestions for future improvement -)

  • 지병윤;황진성;정도현;권형근
    • 농업과학연구
    • /
    • 제42권4호
    • /
    • pp.341-346
    • /
    • 2015
  • This study was conducted to investigate the awareness tendency of the government employees who manage forest roads about problems of forest road use and how to improve them in the future using surveys. The results show there are more silvicultural operations than harvesting operations using forest roads. The main purpose of using forest roads is to transport workers; however, the road will be used more for harvesting operations in the future. The respondents wanted to be accessibility for forest operations within 200 m from road in both present and future. For silvicultural operations 1-ton vehicle is used at present, and 5-ton vehicles are expected to be used in the future. For harvesting operations 5-ton vehicle is used at present, and 10-ton vehicles are will be used in the future. The roadway width is 3 - 4 m at present, but should be 4 - 4.5 m in the future. The longitudinal gradient of roads is 7 - 10% at present, and will be below 10% in the future. The minimum curve radius of roads is 12 - 15 m at present, and will be 15 - 20 m in the future. The results provide basic data for making future forest road policies.

현행 약사연수교육의 문제점과 개선방안에 대한 연구 (Problems and Possible Improvement for Current Continuing Education of Pharmacists)

  • 유연미;스리니바산 샨무감;유동주;용철순;유봉규
    • 약학회지
    • /
    • 제51권6호
    • /
    • pp.469-475
    • /
    • 2007
  • The aim of this study is to find problems and possible improvement for current continuing education (CE) of pharmacists by assessing present status and performing survey data analysis. Present CE for pharmacists is administered by Korean Pharmaceutical Association and it has three separate modules for pharmacists depending on their specialty. The modules for community pharmacy and hospital pharmacy are mainly focused on patient care while the module for industrial pharmacists is on manufacturing and distribution of drugs. Survey data analysis revealed that more than half of the responders feel that present CE is inappropriate in terms of length and contents of the CE. Furthermore, about 40% of all responders answered it does not help them update professional knowledge. With regard to possible improvement of CE, 86% of the responders felt an accreditation council of CE needs to be established, and 64% answered that present three separate modules should be unified. More than three quarter (79%) of the responders wanted to have some part of CE administered by correspondence instead of on-site CE. Based on the findings from this study, present CE for pharmacists appears to need improvement to ensure appropriate drug use and to meet expectations of pharmacists who see problems on the present CE.

다중 블록 암호 알고리듬을 지원하는 암호 프로세서 (A Crypto-processor Supporting Multiple Block Cipher Algorithms)

  • 조욱래;김기쁨;배기철;신경욱
    • 한국정보통신학회논문지
    • /
    • 제20권11호
    • /
    • pp.2093-2099
    • /
    • 2016
  • PRESENT, ARIA, AES의 3가지 블록 암호 알고리듬을 지원하는 다중 암호 프로세서 설계에 대해 기술한다. 설계된 암호 칩은 PRmo (PRESENT with mode of operation), AR_AS (ARIA_AES) 그리고 AES-16b 코어로 구성된다. 64-비트 블록암호 PRESENT를 구현하는 PRmo 코어는 80-비트, 128-비트 키 길이와 ECB, CBC, OFB, CTR의 4가지 운영모드를 지원한다. 128-비트, 256-비트 키 길이를 지원하는 AR_AS 코어는 128-비트 블록암호 ARIA와 AES를 자원공유 기법을 적용하여 단일 데이터 패스로 통합 구현되었다. 128-비트 키 길이를 지원하는 AES-16b 코어는 저면적 구현을 위해 16-비트의 데이터패스로 설계되었다. 각 암호 코어는 on-the-fly 키 스케줄러를 포함하고 있으며, 평문/암호문 블록의 연속적인 암호/복호화 처리가 가능하다. FPGA 검증을 통해 설계된 다중 블록 암호 프로세서의 정상 동작을 확인하였다. $0.18{\mu}m$ 공정의 CMOS 셀 라이브러리로 합성한 결과, 54,500 GEs (gate equivalents)로 구현이 되었으며, 55 MHz의 클록 주파수로 동작 가능하다.

경량 암호 알고리즘 HIGHT와 PRESENT의 저전력 매체(Arduino)에서의 성능 비교 (Benchmark of Lightweoght Block Ciphers (HIGHT & PRESENT) for Arduino)

  • 김나영;신동;김병만
    • 한국정보처리학회:학술대회논문집
    • /
    • 한국정보처리학회 2015년도 추계학술발표대회
    • /
    • pp.875-877
    • /
    • 2015
  • IoT 환경의 센서 네트워크와 RFID 태그 등에서의 AES나 SEED에 대응 할 수 있는 새로운 저전력 경량화 암호 알고리즘이 필요 해짐에 따라 본 논문에서는 2006년 국내에서 제안된 HIGHT와 2007년 CHES에서 제안된 PRESENT 알고리즘을 Arduino에 적용하여 성능을 비교분석 하였다. 그 결과 HIGHT 알고리즘이 PRESENT알고리즘에 비하여 더 짧고, 적은 수행시간과 프로그램 메모리 사용량을 보였으며, 더 많은 동적 메모리 사용량을 보였다.