• 제목/요약/키워드: conservation law

검색결과 305건 처리시간 0.029초

유량 보존 경계 조건을 적용한 커넥팅 로드 베어링의 EHL 해석 (EHL Analysis of Connecting Rod Bearings Using Mass-Conserving Boundary Condition)

  • 김병직;김경웅
    • 한국윤활학회:학술대회논문집
    • /
    • 한국윤활학회 1998년도 제27회 춘계학술대회
    • /
    • pp.212-217
    • /
    • 1998
  • Reynolds equation, which describes behavior of fluid film in journal bearing, basically satisfies mass conservation. But, boundary conditions usually used with this equation, e.g. half Sommerfeld or Reynolds boundary conditions, cannot fulfill this natural law of conservation. In the case of connecting rod bearing, where applied load is dynamic and its magnitude is relatively large, such unrealistic boundary conditions have serious influence on calculation results, especially on lubricant flow rate or power dissipation which are important parameters in thermal analysis. Another important factor in the analysis of connecting rod bearing is elastic deformation of bearing support structure which is relatively flexible. In this paper, EHL analysis of connecting rod beating is performed using mass-conserving boundary condition. Elastic deformation of bearing support structure and application of mass-conserving boundary condition have significant effects on the performances of connecting rod bearing.

  • PDF

A SEMI-LAGRANGIAN METHOD BASED ON WENO INTERPOLATION

  • Yi, Dokkyun;Kim, Hyunsook
    • 충청수학회지
    • /
    • 제28권4호
    • /
    • pp.623-633
    • /
    • 2015
  • In this paper, a general Weighted Essentially Non-Oscillatory (WENO) interpolation is proposed and applied to a semi-Lagrangian method. The proposed method is based on the conservation law, and characteristic curves are used to complete the semi-Lagrangian method. Therefore, the proposed method satisfies conservation of mass and is free of the CFL condition which is a necessary condition for convergence. Using a several standard examples, the proposed method is compared with the third order Strong Stability Preserving (SSP) Runge-Kutta method to verify the high-order accuracy.

건축설비의 에너지보존 계획

  • 명현국
    • 대한설비공학회지:설비저널
    • /
    • 제29권9호
    • /
    • pp.56-62
    • /
    • 2000
  • 1997년 12월 일본 교토에서 개최된 COP3를 계기로 1999년 3월 에너지보존법이 대폭적으로 개정 및 강화되어졌다. 지구온난화의 주된 원인이 되는 이산화탄소는 에너지와 밀접한 관계를 가지고 있으므로, 에너지보존·자원보존의 추진은 지구온난화 대책의 추진과 동등한 의미를 가지고 있다고 하여도 과언이 아니다. 여기서는 건축설비계획의 관점에서 에너지보존법 개정의 요점과 그 대응책에 관해서 개요를 소개하였다.

  • PDF

농촌경관의 보전 및 개선을 위한 경관사업의 도입 방안 연구 (A Study on Introducing the Landscape Project for Conservation and Improvement of Rural Landscape)

  • 신지훈
    • 농촌계획
    • /
    • 제16권4호
    • /
    • pp.77-86
    • /
    • 2010
  • The purpose of this study is to introduce the landscape project for conservation and improvement of rural landscape. So, in this study, the current rural landscape policies and rural landscape planning are examined and the landscape project presented in Landscape Law is also examined. And this study propose the systemic application of the landscape project through the survey of experts related with the landscape project. The results are summarized as follows. Firstly, it is important that each landscape projects are unified for conserve and improve rural landscape. Secondly, it is necessary to define range, enforcement agency, and management agency of landscape projects. Thirdly, it is desirable that the landscape projects should be carried out as reviving the local economies. Comparing to the urban landscape plan, there are few rural landscape plans so far, so, it is difficult to applicate the system of the landscape project, but, continuous studies in this line can help the rural landscape plan to ensure practicality.

Flyback switching loss analysis by capacitor charge and energy conservation

  • Jin, ChengHao;Chung, Bong-Geun;Moon, SangCheol;Koo, Gwan-Bon
    • 전력전자학회:학술대회논문집
    • /
    • 전력전자학회 2015년도 전력전자학술대회 논문집
    • /
    • pp.179-180
    • /
    • 2015
  • The task of measuring losses becomes more challenging with ever increasing efficiencies and operating frequencies in power electronics applications. Generally, the process of traditional switching loss calculation in flyback converter is very complicated. MOSFET drain-source voltage and current waveforms are needed to calculate switching loss. However, as we know in switched capacitor converter, switching loss can be easily calculated by charge and energy conservation law with known initial and final capacitor voltages. In this paper, the same method is applied to fly-back converter switching loss analysis to simplify calculation procedure.

  • PDF

일제강점기 문화재 법제 연구 - 「조선보물고적명승천연기념물보존령(1933년)」 제정·시행 관련 - (A Study of the Cultural Legislation of Historic Properties during the Japanese Colonial Period - Related to the Establishment and Implementation of the Chosun Treasure Historic Natural Monument Preservation Decree (1933) -)

  • 김종수
    • 헤리티지:역사와 과학
    • /
    • 제53권2호
    • /
    • pp.156-179
    • /
    • 2020
  • 「보존령(1933년)」은 식민지 조선의 문화재 보존에 관한 기본 법령으로서 앞서 시행된 일본의 근대 문화재 법제인 「고사사보존법(1897년)」, 「사적명승천연기념물보존법(1919년)」, 「국보보존법(1929년)」 등의 영향을 받았으며, 실제 그들 법령의 해당 법조문을 원용하였다. 이로써 「보존령」이 조문 구성에 있어서 일본 근대 문화재 법제를 이식 또는 모방하였다는 사실은 어느 정도 입증된다고 할 수 있다. 「보존령」의 주요 특징과 성격을 요약하면 다음과 같다. 첫째, 문화재 보존 측면에서 볼 때, 「보존령」은 기존 「보존규칙」보다 보존을 강화하고 확대하였다. 「보존규칙」에서는 문화재 범주를 고적과 유물로 한정했으나 「보존령」에서는 보물, 고적, 명승, 천연기념물 등 4가지로 문화재를 분류하였다. 또한 「보존령」은 문화재 보존 기준을 설정하고 문화재 범위를 확대하였으며, 소유권 제한에 대한 명시적 규정과 문화재 지정제도를 도입함과 동시에 국고 보조 지원 근거를 규정함으로써 문화재 보존 법제로서 진일보한 것으로 평가된다. 둘째, 그러나 「보존령」은 식민지 문화재 법제로서 한계를 가지고 있었다. 「보존령」 제1조에서 보물의 지정 기준으로 "역사의 증징(證徵) 또는 미술의 모범"이란 기준을 설정하였으나 이 기준은 일제의 관점에서 총독부의 동화정책에 입각하여 문화재를 취사선택하는 기준으로 작용하여 문화재 보존 기준으로서 한계를 드러내었다. 또한, 일제는 「보존령」의 시행으로 문화재 법제가 완비되어 문화재 도굴이 감소하였다고 평가하였으나 「보존령」 시행 이후에도 도굴과 밀매매 그리고 일본으로의 반출 등 문화재 약탈과 반출은 끊이지 않았다. 이것은 일반적인 도굴과 밀매 외에도 법령을 준수하고 수호해야 할 총독과 총독부 관료들이 약탈과 반출의 당사자가 되거나 그들의 묵인하에 일본인들에 의한 문화재 약탈과 반출이 지속적으로 자행되었기 때문이다. 이는 당시 문화재 법제가 총독부가 허용한 또는 묵인한 반출과 약탈에는 법적기능을 제대로 발휘하지 못했다는 사실을 알려 준다. 이처럼 일제강점기의 문화재 법령은 문화재 지정과 보존에 있어서 총독부의 시각에서 선택되고 적용된 식민지의 차별적 법제였으며, 일제의 문화재 정책 또한 그들의 동화정책을 실현하는 수단으로 문화재를 이용하는 데 초점이 맞춰졌다. 따라서 일제강점기 문화재 법제는 일제의 조선에 대한 문화적 식민 지배 체제를 공고히 하고 총독부의 동화정책을 실현하는 기제로 활용되었다고 할 수 있다.

중국 성곽유적의 보존 및 관리 (A Study on the City Wall Ruins Preservation and Management of China)

  • 강태호;리아오페이
    • 건축역사연구
    • /
    • 제26권5호
    • /
    • pp.27-38
    • /
    • 2017
  • The main objective of this study is to analyze the preservation and management for the city wall ruins of China, and to find out the implications. Firstly, Chinese walls have experienced a process from demolition to protection. The walls of the historical value of the site are gradually being certified, and many walls ruins were designated as a conservation unit. Secondly, China's institutional system is based on the central government issued Cultural Relics P rotection Law and combined with the actual situation of local governments to establish a special law. Management System is Cultural Relics Bureau, the planning department, the garden department and the tourism sector joint implementation. Thirdly, through the study of Nanjing, Xian, Pingyao, Suzhou city wall ruins finding that perfect legislation and unified management system to help protect city wall ruins.

독일의 생태학적 조경계획 정책분석 -독일 자연환경보존법을 중심 으로- (Analysis of Ecological Landscape Planning and Policy in Germany)

  • 김용수;;나정화
    • 한국조경학회지
    • /
    • 제22권2호
    • /
    • pp.105-122
    • /
    • 1994
  • The landscape plannings were composed of the fundamental provisions which are important factors for the city and local plannings in Germany. The State Government run institute like LOLF in NRW have been established to solve the serious ecological problems. The institute have completed the basic system covering various ecological problems, such as environmental affection analysis and ecological risk, to contribute the application of the various land-using plants. The ecological landscape plannings are regarded as major fundamental plans of environmental preservation for the plannings development. The problems about the local landscape plannings needed to be preserved ecologically are introduced into the Federal Nature Preservation Law and State Congress Law in order to carry out the environmental protection policy effectively. The local landscape plannings are divided into two-step models by the special classification system for the planning. One is build-up of an independent design separated from city plans functionally, and the other is a systematic regulation for cooperation between the local plans and ecological conservation functions. The local plannings including lands to be preserved as the Nature Preservatin Zone is classified a rest area total sectioned plains.

  • PDF

Low & Intermediate Level Radioactive Waste Vitrification Using Plasma Arc Melting Technology

  • Min Byeong-Yeon
    • Nuclear Engineering and Technology
    • /
    • 제35권5호
    • /
    • pp.482-496
    • /
    • 2003
  • effectiveness of the PAM graphite-electrode technology for the treatment of many types of low-level radioactive waste including : combustible material, solidified resins in cement, inorganic materials, steel, glass, and solidified boric acid cement. The objectives of PAM-200 evaluation were to verify that 1) the facility meets air emission regulations, 2) the facility can be safely operated when processing hazardous and radioactive materials and 3) satisfactory final waste forms can be produced. Results, derived from KAERI's(Korea Atomic Energy Research Institute) analyses for samples of vitrified product, scrubbing solution and offgas collected during test period, show that PAM-200 can treat radioactive wastes as well as hazardous wastes with toxic constituents and radionuclides contained in the offgas exiting from the stack to the environment controlled to be far lower than the limit regulated by air conservation law and atomic law.

냉난방 시스템의 이중선형 시스템에 관한 제어기 설계 (A Controller Design of the Bilinear System for HVAC(Heating, Ventilating and Air-conditioning) System)

  • 이정석;강민수;김명호;이기서
    • 한국철도학회논문집
    • /
    • 제3권4호
    • /
    • pp.177-184
    • /
    • 2000
  • In this paper, a HVAC controller which has a bilinear system is designed to control the air temperature in building room and a saving of energy on the HVAC system. For modeling of the HVAC bilinear system, AHU(Air Handling Unit) is modeled on the control of inside-outside air flow using three dampers in a duct. A heat exchanger and the single room are also modeled by the energy conservation law. Under the modeling of the HVAC bilinear system, the control's law of the bilinear HVAC system is derived by Lyapunov's non-linear theory and Deress's the linear feedback laws for bilinear system. In this paper it was proved that the controller of the HVAC bilinear system is able to control the air temperature with a disturbance in order to get a target of temperature in the building room by the computer simulation when the control inputs regulate the air flow rate and a capacity of the heat exchanger.

  • PDF