2019 ◽  
Author(s):  
Víctor Gabriel Baldovino Medrano ◽  
Karen V. Caballero ◽  
Hernando Guerrero-Amaya

Turnover rates for glycerol esterification with acetic acid over Amberlyst-35 were measured under different temperatures, reactants and active sites concentrations, and catalyst particle sizes. Data were collected in a batch reactor. Experiments were done following a sequence of factorial experimental designs.


Author(s):  
E. Widener ◽  
S. Tatti ◽  
P. Schani ◽  
S. Crown ◽  
B. Dunnigan ◽  
...  

Abstract A new 0.5 um 1 Megabit SRAM which employed a double metal, triple poly CMOS process with Tungsten plug metal to poly /silicon contacts was introduced. During burn-in of this product, high currents, apparently due to electrical overstress, were experienced. Electrical analysis showed abnormal supply current characteristics at high voltages. Failure analysis identified the sites of the high currents of the bum-in rejects and discovered cracks in the glue layer prior to Tungsten deposition as the root cause of the failure. The glue layer cracks allowed a reaction with the poly/silicon, causing opens at the bottom of contacts. These floating nodes caused high currents and often latch-up during burn-in. Designed experiments in the wafer fab identified an improved glue layer process, which has been implemented. The new process shows improvement in burn in performance as well as outgoing product quality.


1990 ◽  
Vol 67 (7) ◽  
pp. 593 ◽  
Author(s):  
John R. Amend ◽  
Ronald P. Furstenau ◽  
Kathleen Tucker

Author(s):  
George Ayers ◽  
Kody Sparks ◽  
Kevin Gill
Keyword(s):  

2011 ◽  
Vol 189-193 ◽  
pp. 3633-3639
Author(s):  
Ming Der Jean ◽  
Yih Hwang Yang ◽  
Tzu Hsuan Chien

This study presented the desirability function based on Taguchi designed experiments to solve multiple responses statistical optimal problems for the tungsten carbide/cobalt (WC-Co) coatings of high-velocity-oxygen-fuel (HVOF) processes. The eight control factors based on L18 arrays were conducted and the multi-responses of wear-resistant coatings such as hardness, deposited thickness and wear rate were evaluated simultaneously in the desirability-based experiments. Based on desirability analysis, the optimal settings have been identified, and the impacts of control factors are determined by analysis of variance on the multi-responses. Further, a confirmation run was conducted to validate the tests. Experimental results have shown that the hardness increased by 16.61% and the deposited thickness improved by 10.50%, while the wear rate decreased by 34.03%. It was clear that confirmation tests are greatly improved by way of the desirability-based multi-responses on HVOF WC-Co experiments, and these findings achieved the desired values on wear-resistant coatings. The proposed procedure was applied at HVOF sprayed WC-Co experiments, and the implementation results demonstrated its feasibility and effectiveness to maximize hardness, make a target of deposited thickness value and minimize wear rate by a HVOF.


2002 ◽  
Vol 56 (3) ◽  
pp. 337-345 ◽  
Author(s):  
S. Kamaledin Setarehdan ◽  
John J. Soraghan ◽  
David Littlejohn ◽  
Daran A. Sadler

2012 ◽  
Vol 11 (01) ◽  
pp. 27-50 ◽  
Author(s):  
A. J. JEGADHEESON ◽  
L. KARUNAMOORTHY ◽  
N. ARUNKUMAR ◽  
A. BALAJI ◽  
M. RAJKAMAL

Evolution is "understanding and overcoming current constraints in small steps toward optimum." "Understanding" requires elucidation of facts and corroborating theories that can explain those facts in a coherent manner. "Overcoming" requires self-development to suit the environment. In this paper, a case study about how a manufacturing process is improved in terms of productivity and quality using evolutionary improvements is explained. Here "Understanding" is achieved through use of Shainin Technique, PM analysis, Affinity Diagram, and the engineer's ingenuity, along with Relations diagram. "Overcoming" is achieved through Geometrical Analysis and Designed Experiments. The Study has set a new benchmark in the Stator riveting process by proving it can yield the desired results, and the need to adapt welding process is avoided.


1983 ◽  
Vol 245 (5) ◽  
pp. R664-R672 ◽  
Author(s):  
S. Hurwitz ◽  
S. Fishman ◽  
A. Bar ◽  
M. Pines ◽  
G. Riesenfeld ◽  
...  

The system that regulates plasma calcium in the bird has been formalized into a model based on a series of differential equations and solved by computer simulation. Bone, kidney, and intestine have been considered as the control subsystems, with parathyroid hormone and 1,25-dihydroxycholecalciferol as the regulating hormones. The parameters used in the simulation model have been computed either from published results or by specifically designed experiments described here. For the estimation of parameters, an iterative procedure has been developed that was designed to minimize the sum of square errors between observed and system-simulated values. Parameters of 1,25-dihydroxycholecalciferol metabolism were experimentally obtained from the kinetic behavior of the 3H-labeled hormone in rachitic birds after a single dose. Model parameters have been adjusted using the results of in vivo calcium loading and validated by an EDTA infusion experiment. The simulation model has been used to study the hierarchy of the activities of the three control subsystems and of the regulating hormones, at different calcium intakes. Positive or negative errors in plasma calcium resulted in an asymmetry in the activities of the controlling systems, bone and kidney, whereas the intestine is characterized by its relatively long response time.


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