• Title/Summary/Keyword: Non-equilibrium

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A Digitized Decoupled Dual-axis Micro Dynamically Tuned Gyroscope with Three Equilibrium Rings

  • Xia, Dunzhu;Ni, Peizhen;Kong, Lun
    • Journal of Electrical Engineering and Technology
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    • v.12 no.1
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    • pp.385-395
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    • 2017
  • A new digitized decoupled dual-axis micro dynamically tuned gyroscope with three equilibrium rings (TMDTG) is proposed which can eliminate the constant torque disturbance (CTD) caused by the double rotation frequency of a driving shaft with a micro dynamically tuned gyroscope with one equilibrium ring (MDTG). A mechanical and kinematic model of the TMDTG is theoretically analyzed and the structure parameters are optimized in ANSYS to demonstrate reliability. By adjusting the thickness of each equilibrium ring, the CTD can be eliminated. The digitized model of the TMDTG system is then simulated and examined using MATLAB. Finally, a digitized prototype based on FPGA is created. The gyroscope can be dynamically tuned by adjusting feedback voltage. Experimental results show the TMDTG has good performance with a scale factor of $283LSB/^{\circ}/s$ in X-axis and $220LSB/^{\circ}/s$ in Y-axis, respectively. The scale factor non-linearity is 0.09% in X-axis and 0.13% in Y-axis. Results from analytical models, simulations, and experiments demonstrate the feasibility of the proposed TMDTG.

The Influence of the Structural Parameters on the Shape Errors of CRTS Reflector (CRTS 반사판의 구조적 인자가 형상오차에 미치는 영향)

  • 송원근;김승덕
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.16 no.1
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    • pp.87-94
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    • 2003
  • A geometric non-linear finite element formulation of CRTS reflector subjected to displacement loads, corresponding to the successional assembly steps of the reflector, is presented in order to determine the initial static equilibrium state based on the displacement incremental method. Parametric analyses of the influence of cables and mechanical properties of the reflector on the shape error between reference and equilibrium surfaces have been studied. These results of the present study are compared with the others using Galerkin mothod and NASS 98 program to demonstrate the feasibility.

Investigation of 180W separation by transient single withdrawal cascade using Salp Swarm optimization algorithm

  • Morteza Imani;Mahdi Aghaie
    • Nuclear Engineering and Technology
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    • v.55 no.4
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    • pp.1225-1232
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    • 2023
  • The 180W is the lightest isotope of Tungsten with small abundance ratio. It is slightly radioactive (α decay), with an extremely long half-life. Its separation is possible by non-conventional single withdrawal cascades. The 180W is used in radioisotopes production and study of metals through gamma-ray spectroscopy. In this paper, single withdrawal cascade model is developed to evaluate multicomponent separation in non-conventional transient cascades, and available experimental results are used for validation. Numerical studies for separation of 180W in a transient single withdrawal cascade are performed. Parameters affecting the separation and equilibrium time of cascade such as number of stages, cascade arrangements, feed location and flow rate for a fixed number of gas centrifuges (GC) are investigated. The Salp Swarm Algorithm (SSA) as a bio-inspired optimization algorithm is applied as a novel method to minimize the feed consumption to obtain desired concentration in the collection tank. Examining different cascade arrangements, it is observed in arrangements with more stages, the separation is further efficient. Based on the obtained results, with increasing feed flow rate, for fixed product concentration, the cascade equilibrium time decreases. Also, it is shown while the feed location is the farthest stage from the collection tank, the separation and cascade equilibrium time are well-organized. Finally, using SSA optimal parameters of the cascade is calculated, and optimal arrangement to produce 5 gr of 180W with 90% concentration in the tank, is proposed.

ON GENERALIZED WEIGHT NASH EQUILIBRIA FOR GENERALIZED MULTIOBJECTIVE GAMES

  • Kim, Won-Kyu;Ding, Xie-Ping
    • Journal of the Korean Mathematical Society
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    • v.40 no.5
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    • pp.883-899
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    • 2003
  • In this paper, we will introduce the general concepts of generalized multiobjective game, generalized weight Nash equilibria and generalized Pareto equilibria. Next using the fixed point theorems due to Idzik [5] and Kim-Tan [6] , we shall prove the existence theorems of generalized weight Nash equilibria under general hypotheses. And as applications of generalized weight Nash equilibria, we shall prove the existence of generalized Pareto equilibria in non-compact generalized multiobjective game.

Solids 3-D with bounded tensile strength under the action of thermal strains. Theoretical aspects and numerical procedures

  • Pimpinelli, Giovanni
    • Structural Engineering and Mechanics
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    • v.18 no.1
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    • pp.59-78
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    • 2004
  • This paper is devoted to illustrate some numerical procedures to solve the boundary equilibrium problems of three-dimensional solids that are subjected to thermal strains. The constitutive equations take into account the bounded tensile strength of the material and they are presented in the framework of non-linear elasticity and small strains. The associated equilibrium problem is solved numerically by means of the finite element method and the numerical techniques, i.e. the Newton-Raphson method and the secant method, are revised in order to assure the solution convergence of the discretized problem. Some numerical examples are illustrated.

Estimating the Price of Anarchy Using Load Balancing Measure

  • Kim, Jae-Hoon
    • Journal of information and communication convergence engineering
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    • v.7 no.2
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    • pp.148-151
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    • 2009
  • We consider the problem of optimizing the performance of a system with resources shared by non-cooperative users. The worst-cast ratio between the cost of a Nash equilibrium and the optimal cost, called Price of Anarchy, is investigated. It measures the performance degradation due to the users' selfish behavior. As the objective function of the optimization problem, we are concerned in a load balancing measure, which is different from that used in the previous works. Also we consider the Stackelberg scheduling which can assign a fraction of the users to resources while the remaining users are free to act in a selfish manner.

Development of Gas/Particle Transport Mechanism using Modal Dynamics Approach with Global Equilibrium Method (Modal Dynamics 방법과 광역적 평형 방법을 이용한 기체/입자간 물질이동모델 개발)

  • 정창훈;김용표;이규원
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2000.11a
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    • pp.215-216
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    • 2000
  • 대기 중에 존재하는 입자의 생성 및 변화를 모델링 하는데 있어서 가장 중요한 요소는 응축/휘발 (condensation/evaporation)과 같은 기체/입자간의 상호 과정을 어떻게 모사 하느냐 하는 것이다. 일반적으로 지금까지의 연구는 입자와 가스상의 농도가 순간적으로 평형을 이룬다고 가정해 왔으나 실제 대기상의 입자는 비 평형(non-equilibrium)상태의 응축/휘발 과정을 따르는 것으로 알려져 왔다. (중략)

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