• Title/Summary/Keyword: Conservation state

Search Result 463, Processing Time 0.029 seconds

A NUMERICAL ALGORITHM FOR ELASTO-PLASTIC MATERIAL DEFORMATION

  • HWANG HYUN-CHEOL
    • Communications of the Korean Mathematical Society
    • /
    • v.20 no.3
    • /
    • pp.589-602
    • /
    • 2005
  • We present the numerical algorithm for the model for high-strain rate deformation in hyperelastic-viscoplastic materials based on a fully conservative Eulerian formulation by Plohr and Sharp. We use a hyperelastic equation of state and the modified Steinberg and Lund's rate dependent plasticity model for plasticity. A two-dimensional approximate Riemann solver is constructed in an unsplit manner to resolve the complex wave structure and combined with the second order TVD flux. Numerical results are also presented.

The Geographic Environment of Hwaam Cave Area

  • Hong, Chung-Ryol;Won, Pyong-Kwan
    • Journal of the speleological society of Korea
    • /
    • no.4
    • /
    • pp.23-32
    • /
    • 1996
  • The geographic environment means the general state of the environment in the area. Especially, which means the generation cause, the development process of the cave, and the validity of cave development and conservation in the side of the place of the cave. This study put emphasis on lying in which place Hwaam cave in Tong-myon, Chong son-gun, Kangwondo is situated and having in which stand is in comparison with other districts, and how the geological structure which determine the cave forming cause is.(omitted)

  • PDF

Industrial, Commercial, and Institutional Water Conservation and Reuse Programs In Texas(A State Level Perspective) (Texas주의 상.공업지역 및 공공기관에서의 수자원 보존과 재이용 사업계획에 대한 주정부 차원의 전망)

  • Wm Herman
    • 수도
    • /
    • v.24 no.4 s.85
    • /
    • pp.69-74
    • /
    • 1997
  • ICI 프로그램에서 보는 바와 같이 주정부의 주된 역할은 지방의 프로그램을 지원해주는 것이다. 이 지원은 ICI 사업계획의 목적달성을 위한 정책과 규정을 수립하는 것이다. 즉, 재정적 보상, 연구, 훈련 및 기술지원 등이다. 향후 장기계획수립에 ICI보전 및 재이용 가능성을 포괄하는 수자원보전 및 재이용에 관한 내용을 포함한다. 그러나 중요한 사실은 항상 각 지방의 프로그램을 지원해 주는데 초점을 맞추는 것이어야 한다.

  • PDF

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

  • ;L, Finke
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.22 no.2
    • /
    • 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

Theoretical Analysis of Steady State Low Current Arcs in Dual Flow Nozzles

  • Song, K.D.;Shin, Y.J.;Lee, H.S.;Kim, K.S.
    • Proceedings of the KIEE Conference
    • /
    • 1992.07b
    • /
    • pp.952-957
    • /
    • 1992
  • When the circuit-breaker switches off, an electric arc is established between the contacts. It is very important to understand the arc characteristics for the design of a circuit breaker. This article describes the theoretical analysis of the arc characteristics by means of energy integral method when convection dominated low current arcs are produced in the dual-airflow nozzle of a model interrupter. In order to investigate the arc radius, the average electric field strength and the arc voltage, the arc column is divided into two regions, and then the energy conservation equation is applied to the arc in each region together with the axial cold flow mass flux function, steady-state mass balance equation and Ohm's law. The results show good agreements with those of other researchers.

  • PDF

Comparing Two Approaches of Analyzing Mixed Finite Volume Methods

  • Chou, So-Hsiang;Tang, Shengrong
    • Journal of the Korean Society for Industrial and Applied Mathematics
    • /
    • v.5 no.1
    • /
    • pp.55-78
    • /
    • 2001
  • Given the anisotropic Poisson equation $-{\nabla}{\cdot}{\mathcal{K}}{\nabla}p=f$, one can convert it into a system of two first order PDEs: the Darcy law for the flux $u=-{\mathcal{K}{\nabla}p$ and conservation of mass ${\nabla}{\cdot}u=f$. A very natural mixed finite volume method for this system is to seek the pressure in the nonconforming P1 space and the Darcy velocity in the lowest order Raviart-Thomas space. The equations for these variables are obtained by integrating the two first order systems over the triangular volumes. In this paper we show that such a method is really a standard finite element method with local recovery of the flux in disguise. As a consequence, we compare two approaches in analyzing finite volume methods (FVM) and shed light on the proper way of analyzing non co-volume type of FVM. Numerical results for Dirichlet and Neumann problems are included.

  • PDF

Numerical Simulation of a Reciprocating Compressor (왕복동 압축기의 성능해석 시뮬레이션)

  • 김정우;김현진;박희용
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.17 no.2
    • /
    • pp.475-483
    • /
    • 1993
  • A computer simulation model of a hermetic reciprocating type of refrigeration compressor has been developed. The compressor simulation model constitutes 6 control volumes, to each of which conservation laws of mass and energy are applied to yield full description of the refrigerant state along its passage. Instead of ideal gas assumption. real gas equation is employed. Some of valve-related input data required for the simulation are acquired from test bench experiments. The refrigerant states such as pressure and temperature, etc., mass flow rates, and valve motions can be predicted by the simulation. The calculated P-V diagram shows a good agreement with experimental result.

A Study on the 3-D Unsteady State Heat Transfer Coupled by Conductive Currents (전기장 변화에 따른 3차원 비정상 상태 열전달 연계 해석에 관한 연구)

  • Kwac, L.K.;Kim, H.G.
    • Transactions of the Korean Society of Machine Tool Engineers
    • /
    • v.17 no.1
    • /
    • pp.29-34
    • /
    • 2008
  • A modeling technique for the 2-way coupling of heat transfer and conduction currents has been performed to inspire a combined analytical simulation. The 3-D finite element method is used to solve steady conduction currents and heat generation in an aluminum film deposited on a silicon substrate. The model investigates the temperature in the device after the current is applied. The conservation equation of energy, the Maxwell equations for conduction currents, the unsteady state heat transfer equation and the Fourier's law for heat transfer are implemented as a bidirectionally coupled problem. It is found that the strongly coupled temperature and time dependent heat equations give a reasonable results and an explicit solving technique.

Analysis and control of the falling cat phenomenon

  • Nakagawa, Takayuki;Sampei, Mitsuji;Kiyota, Hiromitsu
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1995.10a
    • /
    • pp.472-475
    • /
    • 1995
  • In this paper, we investigate so-called the falling cat problem. It is well known that a cat, when released from an upside down configuration starting from rest, is able to land on her feet without violating angular momentum conservation. This has being an interesting problem for engineers for a long time. We consider a model of a falling cat as connected two rigid columns, which is a nonholonomic system. We design the controller for it, using time- state control form of the model and exact linearization technique. Finally, we test the controller thorough simulation on the model of a falling cat.

  • PDF

Current status, challenges and prospects for pig production in Asia

  • Lu Wang;Defa Li
    • Animal Bioscience
    • /
    • v.37 no.4_spc
    • /
    • pp.742-754
    • /
    • 2024
  • Asia is not only the primary region for global pig production but also the largest consumer of pork worldwide. Although the pig production in Asia has made great progress in the past, it still is confronted with numerous challenges. These challenges include: inadequate land and feed resources, a substantial number of small-scale pig farms, escalating pressure to ensure environmental conservation, control of devastating infectious diseases, as well as coping with high temperatures and high humidity. To solve these problems, important investments of human and financial capital are required to promote large-scale production systems, exploit alternative feed resources, implement precision feeding, and focus on preventive medicine and vaccines as alternatives to antibiotics, improve pig breeding, and increase manure recycling. Implementation of these techniques and management practices will facilitate development of more environmentally-friendly and economically sustainable pig production systems in Asia, ultimately providing consumers with healthy pork products around the world.