scholarly journals Rancang Bangun Mesin Laser Engraver and Cutter Untuk Membuat Kemasan Modul Praktikum Berbahan Akrilik

2020 ◽  
Vol 2 (1) ◽  
pp. 40-50
Author(s):  
Aris Eko Saputro ◽  
Mochammad Darwis
Keyword(s):  
Laser Diode ◽  
Life Time ◽  
Two Dimensional ◽  
Laser Head ◽  
Practical Tool ◽  
Vocational Institution

In the competence of vocational institution, lecturers, students and PLP staff are expected to make their own appropriate equipment. An educational laboratory as a place to provide adequate practice and supporting equipments. Equipment or innovations that are designed must be packaged in an attractive form as a prototype of a product. As for the research and or as a practical tool in the laboratory. The packaging also serves to protect the device made and increase its life time. Usually the material used to make a casing material is acrylic. The thicker the acrylic, the more difficult it is to make. Laser engraver or laser cutter as a solution to facilitate the manufacture of casings that made from acrylic. User will create a two-dimensional design using a program, such as Inkscape. Then the design is saved or changed into gcode. The resulting gcode file is then sent to the laser engraver to make the design. The power of the laser head used, will determine the thickness of the acrylic to be cut. In this research, 2 mm thick acrylic was tested using a 15W laser diode module.

scholarly journals SDAR: a practical tool for graphical analysis of two-dimensional data

2012 ◽  
Vol 13 (1) ◽  
pp. 201 ◽  
Author(s):  
Saroja Weeratunga ◽  
Nien-Jen Hu ◽  
Anne Simon ◽  
Andreas Hofmann
Keyword(s):  
Graphical Analysis ◽  
Two Dimensional ◽  
Practical Tool

scholarly journals Study of a Li-Ion Cell Kinetics in Five Regions to Predict Li Plating Using a Pseudo Two-Dimensional Model

2019 ◽  
Vol 11 (22) ◽  
pp. 6392 ◽  
Author(s):  
Sanaz Momeni Boroujeni ◽  
Kai Peter Birke
Keyword(s):  
Cell Model ◽  
Simulated Data ◽  
Ionic Conductivities ◽  
Life Time ◽  
Einstein Relation ◽  
Side Reactions ◽  
Two Dimensional ◽  
Calculation Results ◽  
Li Ion ◽  
Aging Mechanisms

Detecting or predicting lithium plating in Li-ion cells and subsequently suppressing or preventing it have been the aim of many researches as it directly contributes to the aging, safety, and life-time of the cell. Although abundant influencing parameters on lithium deposition are already known, more information is still needed in order to predict this phenomenon and prevent it in time. It is observed that balancing in a Li-ion cell can play an important role in controlling lithium plating. In this work, five regions are defined with the intention of covering all the zones participating in the charge transfer from one electrode to the other during cell cycling. We employ a pseudo two-dimensional (P2D) cell model including two irreversible side reactions of solid electrolyte interface (SEI) formation and lithium plating (Li-P) as the anode aging mechanisms. With the help of simulated data and the Nernst–Einstein relation, ionic conductivities of the regions are calculated separately. Calculation results show that by aging the cell, more deviation between ionic conductivities of cathode and anode takes place which leads to the start of Li plating.

High-duty cycle, high-power two-dimensional laser diode arrays

1993 ◽  
Vol 29 (11) ◽  
pp. 1008-1010 ◽  
Author(s):  
G.L. Harnagel ◽  
M. Vakili ◽  
K.R. Anderson ◽  
D.P. Worland ◽  
J.G. Endriz ◽  
...  
Keyword(s):  
Laser Diode ◽  
High Power ◽  
Duty Cycle ◽  
Two Dimensional ◽  
High Duty Cycle ◽  
Laser Diode Arrays

On the TCAD Based Design Diagnostic Study of 4H-SiC Based IGBTs

2014 ◽  
Vol 778-780 ◽  
pp. 1034-1037 ◽  
Author(s):  
Muhammad Nawaz ◽  
Filippo Chimento
Keyword(s):  
Experimental Data ◽  
Carrier Mobility ◽  
Minority Carrier ◽  
Life Time ◽  
Diagnostic Study ◽  
Two Dimensional ◽  
Close Match ◽  
Increasing Temperature ◽  
Carrier Life Time ◽  
Drift Layer

This paper addresses the design diagnostic study of 4H-SiC based IGBTs using two dimensional numerical computer simulations. Using identical set of physical device parameters (doping, thicknesses), simulated structure was first calibrated with the experimental data. A minority carrier life time in the drift layer of 1.0 1.6 μs and contact resistivity of 0.5 - 1.0 x 10-4 Ω-cm2 produces a close match with the experimental device. A decay in the device transconductance and threshold voltage is observed with increasing temperature. The on-resistance first decays with temperature (i.e., increased in ionization level, and increase in minority carrier life time), stays nearly constant with further increase in the temperature (may be all carriers are now fully ionized and increase in carrier life time is compensated with decrease in the carrier mobility) and finally increases linearly with temperature (> 450 K) due to decrease in the carrier mobility. The design of buffer layer is investigated that shows lower on-state losses with thin high doped buffers. For the design of devices over 15 20 kV, the design of drift layer demands a doping of < 2.0 x 1014 cm-3 with epitaxial layer quality giving a carrier life time over 2.0 μs.

Advanced Labyrinth Seals for Steam Turbine Generators

2006 ◽  
Author(s):  
Ahmad D. Vakili ◽  
Abraham J. Meganathan ◽  
Sricharan Ayyalasomayajula ◽  
Stephen Hesler ◽  
Lewis Shuster
Keyword(s):  
High Performance ◽  
Internal Flow ◽  
Life Time ◽  
Labyrinth Seal ◽  
Two Dimensional ◽  
Steam Turbines ◽  
Labyrinth Seals ◽  
Turbine Generators ◽  
High Performance Composite ◽  
Steam Leakage

A new class of knives (C-Shaped) for reduced labyrinth seal discharge has been designed and assessed through two dimensional numerical modeling of the seal’s internal flow passages. Modeling procedures used for the analysis have been previously validated by comparison with static labyrinth seal experiments. The objectives of the new seal are to: 1) reduce flow leakage through the seal and 2) introduce structural flexibility in the knives so that design clearances could be maintained even after rub events during startup. The baseline chosen for comparative evaluation is an N2 packing used in GE steam turbines. The new seals have compliant C-shaped knives instead of the straight knives, found in an N2 packing. The best performing configuration has one tall ‘C’ shaped long knife and three ‘C’ shaped short knives in each stage. It was found that the best configuration at clearances similar to the baseline seal reduces flow leakage by 42%. Two dimensional numerical structural analyses showed that the new seal knife is more flexible than a straight knife. This is also intuitive by virtue of its geometric profile. A non-dimensional geometric parameter correlates with the degree of flexibility in the knife. These results indicate a potential for design of labyrinth seals that maintain lower design clearances throughout their life time by carefully selecting the knives’ geometric parameters and incorporating high performance composite materials. Then, the new design would result in significantly lower steam leakage.

Two-dimensional Er:YSGG microlaser array pumped with a monolithic two-dimensional laser diode array

1994 ◽  
Vol 19 (21) ◽  
pp. 1738 ◽  
Author(s):  
Robert Waarts ◽  
James Harrison ◽  
B. J. Dinerman ◽  
Derek Nam ◽  
Steve Sanders
Keyword(s):  
Laser Diode ◽  
Diode Array ◽  
Two Dimensional ◽  
Laser Diode Array
Sign in / Sign up

Export Citation Format

Share Document