scholarly journals Design and Testing of a Compact Optical Prism Module for Multi-Degree-of-Freedom Grating Interferometry Application

2018 ◽  
Vol 8 (12) ◽  
pp. 2495 ◽  
Author(s):  
Xinghui Li ◽  
Yaping Shi ◽  
Xiang Xiao ◽  
Qian Zhou ◽  
Guanhao Wu ◽  
...  
Keyword(s):  
Glass Substrate ◽  
Power Loss ◽  
Incident Beam ◽  
Optical Component ◽  
Degree Of Freedom ◽  
Bottom Surface ◽  
Beam Diameter ◽  
Large Power ◽  
Optical Prism ◽  
Design And Testing

In this research, a key optical component for multi-degree-of-freedom (MDOF) surface encoder was designed, fabricated and evaluated. In a MDOF grating interferometry system, there are four diffraction beams from a two-axis scale grating and reference grating, respectively. For further modulation, these beams will propagate more than 100 mm, which makes paralleling these beams necessary. In previous research, collimation lens, separate prisms and a home fabricated diffraction device by combining four separate one-axis line gratings in a glass substrate have been demonstrated. However, large power loss and assembly complicity makes these techniques less competitive. For solving this problem, this research proposed a new lens module, which is an improved type prism, quadrangular frustum pyramid (QFP) prism. The prism is designed in such a way that these four reflected beams from the grating are symmetrically incident into the prism through the upper surface, total reflected on the inner sides of the prism, and then parallel getting through the bottom surface. A prism that allows an incident beam diameter of 1 mm and four paralleling beams with a 10 mm distance between the two diffraction beams along one direction was designed, fabricated and tested. Testing results based on an entire grating interferometry system verified that the proposal in this research is greatly effective in beam paralleling in terms of less power loss and high paralleling and greatly reduces the assembly complicity, which will eventually be beneficial for grating interferometry application.

scholarly journals Rekonfigurasi Jaringan Distribusi Radial Menggunakan Modified Firefly Algorithms (MFA) Pada Penyulang Tanjung Rayon Jombang

2017 ◽  
Vol 1 (2) ◽  
pp. 13
Author(s):  
Hidayatul Nurohmah ◽  
Agus Raikhani ◽  
Machrus Ali
Keyword(s):  
Artificial Intelligence ◽  
Power Loss ◽  
Electrical Energy ◽  
Network Reconfiguration ◽  
Power Losses ◽  
Large Power ◽  
Artificial Intelligent ◽  
Combination Optimization ◽  
Long Time ◽  
Opening And Closing

Abstract -  Reconfiguring a distribution network is necessary to reduce power loss and increase system reliability.Different distribution forms will affect the large power losses so that it is necessary to reset the network configuration.Reconfiguration is done by opening and closing switches on the best distribution network.The amount of feeder and bus on the network will be difficult and require a very long time if calculated manually.The repeater of Tanjung Rayon Jombang consists of 41 Buses and 44 feeders.Therefore it is necessary to solve the problem by using artificial intelligence or Artificial Intelligent (AI).Firefly Algorithms (FA) widely used research in solving the optimization problem.Modified Firefly Algorithms (MFA) is an FA modification designed to solve discrete combination optimization problems.MFAs can search for the best network reconfiguration so that it can reduce 12,0866 kWatt or 12,6881% in Cape repeater.With the end voltage before reconfiguration 0.92959 pu to 0.94072 pu.This method can later use other artificial intelligence or can be applied to other repeater, thus reducing the losses of electrical energy.

Analysis of delamination of composite laminates via extended finite element method based on the layerwise displacement theory and cohesive zone method

2021 ◽  
pp. 146442072110461
Author(s):  
Matheus VM Santos ◽  
Murilo Sartorato ◽  
Anish Roy ◽  
Volnei Tita ◽  
Marcelo L Ribeiro
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Composite Laminates ◽  
Extended Finite Element Method ◽  
Degree Of Freedom ◽  
Bottom Surface ◽  
Extended Finite Element ◽  
Zone Method ◽  
Displacement Theory ◽  
Element Method

Composite laminates are being more employed as fundamental structures due to its low weight and high stiffness. To predict the material response in presence of damage can be demanding due to composite’s complex nature. Hence, superior computational models should be further investigated to speculate a more accurate composite behavior. This paper proposes an extended finite element procedure, based on the layerwise displacement theory, to simulate delamination to composite laminate. It is assumed a cohesive behavior to the damaged domain, described by a traction separation law. An extra degree of freedom associated to the strong discontinuity (delamination) is added at each layer top and bottom surface for out-of-plane displacement. This extra degree of freedom is only active on the failed nodes. To validate the model, a pre-delaminated composite analysis is performed and compared to results already reported in the literature. In addition, all stress components can be precisely calculated due to layer wise displacement field assumption, without any concern about the membrane and shear locking, not to mention its greater computational efficiency when compared to equivalent three-dimensional elements. Therefore, in the present work, it is shown the limitations and potentialities when a cohezive formulation is combined to extended finite element method using a new kind of approach. Additionally, this formulation makes easier to model delaminations using finite element method keeping a good accuracy without the need of cumbersome finite element models.

Distribution of Hepatic Venous Blood in the Total Cavo Pulmonary Connection: An In Vitro Study Into the Effects of Connection Geometry

2001 ◽  
Vol 123 (6) ◽  
pp. 558-564 ◽  
Author(s):  
Peter G. Walker ◽  
Ghanem F. Oweis ◽  
Kevin G. Watterson
Keyword(s):  
Low Power ◽  
Power Loss ◽  
Heart Defects ◽  
Superior Vena ◽  
Venous Blood ◽  
Vena Cava ◽  
Fluid Distribution ◽  
Large Power ◽  
Zero Offset

The total cavo pulmonary connection, or TCPC, is a surgical correction to congenital heart defects. The geometry of this connection has been shown to determine the fluid power loss as well as the distribution of hepatic fluid that enters through the inferior vena cava. In vitro studies were performed to measure the power loss and hepatic fluid distribution in models of the TCPC with four different geometries. It was found that a zero offset straight geometry provided good hepatic fluid distribution but large power loss. A zero offset flared geometry provided low power loss but poor hepatic fluid distribution. The optimal geometry from those tested was found to be the zero offset cowl geometry whereby an enlargement was made on one side of the inferior and superior vena cava. So long as the cowl was directed toward the pulmonary artery of lowest flow rate, low power loss and relatively good distribution of hepatic flow could be obtained.

Design of Self-Adaptive ZVS Protection Circuit for Electronic Ballast

2012 ◽  
Vol 482-484 ◽  
pp. 1235-1240
Author(s):  
Xian Rui Li ◽  
Qian Liu ◽  
Rui Shen
Keyword(s):  
Power Loss ◽  
Feedback Loop ◽  
Dead Time ◽  
Input Voltage ◽  
Control Circuit ◽  
Large Power ◽  
Power Mosfet ◽  
Time Control ◽  
Protection Circuit ◽  
Self Adaptive

The overlap of the voltage and current of power MOSFET will leads large power loss when power MOSFET in a ballast turns on. To solve this problem, a self-adaptive ZVS protection circuit is proposed, which consists of a dead time control circuit and a ZVS control circuit. Compared with traditional circuit with fixed dead time, it can regulate the dead-time automatically to realize ZVS with a negative feedback loop and result reduction advantages come from, such as the induction of power loss and EMI, meanwhile the efficiency is improved. Hspice simulation shows that the ZVS protection circuit in the ballast with an input voltage of 14V and an operation frequency of 50 kHz can realize the self-adaptive dead time.

Influence of the Operating Conditions of Two-Degree-of-Freedom Planetary Gear Trains on Tooth Friction Losses

2018 ◽  
Vol 140 (5) ◽  
Author(s):  
Essam Lauibi Esmail
Keyword(s):  
Power Loss ◽  
Power Flow ◽  
Planetary Gear ◽  
Operating Conditions ◽  
Degree Of Freedom ◽  
Gear Train ◽  
Friction Loss ◽  
Planetary Gear Trains ◽  
Gear Trains ◽  
Two Degree Of Freedom

In a planetary gear train (PGT), the power loss by tooth friction is a function of the potential power developed within the gear train elements rather than that being transmitted through it. In the present work, we focus on the operating conditions of two-degree-of-freedom (two-DOF) PGTs. Any operating condition induces its own internal power flow pattern; this implies that tooth friction loss depends on the mechanism of power loss developed in the gearing that differs from one case to another over the entire range of operating conditions. The approach adopted in this paper stems from a unification of the kinematics and tooth friction losses of PGTs and is based on potential powers and power ratios. The range of applicability of the power relations is investigated and clearly defined, and tooth friction loss formulas obtained by their use are tabulated. A short comparison with formulas currently available in the literature is also made. The simplicity of the proposed method for analyzing two-input or two-output planetary gear trains is helpful in the design, optimization, and control of hybrid transmissions. It assists particularly in choosing correctly the appropriate operating conditions to the involved application.

scholarly journals Design and Test of a 1 DOF Haptic Device for Online Experimentation

2016 ◽  
Vol 12 (04) ◽  
pp. 55 ◽  
Author(s):  
Fernando Carneiro ◽  
Manuel Rodrigues Quintas ◽  
Paulo Abreu ◽  
Maria Teresa Restivo
Keyword(s):  
Virtual Reality ◽  
Low Cost ◽  
Degree Of Freedom ◽  
Haptic Device ◽  
Online Experimentation ◽  
Design And Testing

This work describes the design and testing of a 1 degree of freedom (DOF) haptic device, for interaction with virtual reality (VR) applications. This device was designed so that it could to be easily assembled by anyone at a reduced price. Instructions for device assembly, as well as some VR appli-cations are available online. The tests performed on the device proved that, despite its low cost, it is able to provide users with a good haptic experience and is adequate for not complex applications.

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