Effect of Humidity on Wear of TiN Coatings: Role of Capillary Condensation

Metallurgical and Materials Transactions A - Coated ball-on-disk wear configuration was used to study the effect of relative humidity, water vapor pressure, and water on wear of TiN coatings in the...     

Equipment selection and justification through total productivity model

Traditional methods of economic analysis to justify equipment selection and use are based on several methods such as the Net Present Value, Break-Even Analysis, Pay-Back Period, Return on Investment, among others. However, with the introduction of automation, Flexible Manufacturing Systems (FMS), and Computer Integrated Manufacturing Systems (CIMS), such economic analyses have often resulted in decisions that management did not like to support but did not have much choice to avoid on account of pressure from manufacturing engineers, design engineers and others in the operations areas. The real problem of equipment selection and justification lies in the methodologies used.

This paper presents a unique approach to equipment justification by applying Sumanth's TOTAL PRODUCTIVITY MODEL, whereby the anticipated impact of the proposed equipment on profitability is assessed from the point of total productivity and the five partial productivities. Then, only if the equipment increases the total productivity level beyond its break even point, the equipment is selected or justified.

This method offers a non-traditional approach to justifying and selecting equipment in all types of environment. A numerical example is presented by using LOTUS 1-2-3^TM on an IBM PC. Advantages and limitations to this approach are discussed to provide a balanced perspective on the important issue of equipment selection and justification.     

A micro computer decision support system for the total-productivity model (TPM)

The Total Productivity Model (TPM), developed by Sumanth in 1979, has been applied to a number of situations involving manufacturing as well as service-oriented operations. The diversity of applications on the one hand, and the flexibility of usage of the microcomputers on the other hand, have helped to focus the need for a micro-computer based Decision Support System (DSS). This paper presents such a system using the Macintosh Computer. This DSS is a highly interactive, menu-driven program that can provide on-the screen capabilities of individual operational units as well as the firm that comprises of them. The system has several convenient features to assess the “PRODUCTIVITY- ORIENTED PROFITABILITY” of any type companies/organizations. The system logic and flow chart, data input and output formats, and sensitivity analysis will be shown and discussed in the paper. A balanced critique will be offered to view the system in a proper perspective with respect to structural elements of the Decision Support System.     

Favorable Environment for a Nondendritic Morphology in Controlled Diffusion Solidification

The novelty of the controlled diffusion solidification (CDS) process is the mixing of two precursor alloys with different thermal masses to obtain the resultant desired alloy, which is subsequently cast into a near-net-shaped product. The critical event in the CDS process is the ability to generate a favorable environment during the mixing of the two precursor alloys to enable a well-distributed and copious nucleation event of the primary Al phase leading to a nondendritic morphology in the cast part. The turbulence dissipation energy coupled with the undercooling of the precursor alloy with the higher temperature enables the copious nucleation events, which are well distributed in the resultant mixture.     

Mechanism and preventive measures for die soldering during Al casting in a ferrous mold

This work provides a comprehensive understanding of the reactions at the ferrous die/molten metal interface in a metal mold casting operation. The literature has shown that several important factors influence reactions at the ferrous die/molten aluminum interface, including temperature of the melt, temperature of the die, alloy chemistry of the melt and die, die surface engineering, topographical features, and coatings. This article discusses the effect of the more critical factors on soldering, based on the authors’ investigations. Inaddition, based on a mechanistic understanding of the interface reactions between ferrous die and molten aluminum, recommendations are given for specific processing issues to alleviate soldering during die casting of aluminum alloys.     

Effect of deposition temperature and Zn composition on structure,optical and electrical properties of CdO thin films

Cd_1?xZn_xO nanocrystallite films with doping concentrations varied from x?=?0.00–0.90 were synthesized through a simple chemical route of the spray pyrolysis process using 0.05M precursor solution. The suitable optimized temperatures for different compositions films were obtained by adjusting deposition temperatures from 693 to 723 K. It was found that structures, surface morphology, optical and electrical properties of the films can be altered by changing Zn contents in CdO deposits. The film composition from x?=?0 to 0.50 have shown cubic phase with (1 1 1) prominent plane and the composition x?=?0.90 shown wurtzite structure with (1 0 1) prominent plane. However, the composition varied from x?=?0.60 to 0.80, in the deposits which showed mixed structure of cubic and wurtzite. The crystallite size, dislocation density and microstrain have been evaluated using XRD data. Scanning electron microscope images have shown different surface morphologies for different Zn doped CdO films. The absorption edge was found to be a blue shift with the increase of Zn content, confirming that there is an increase in the optical band gap. Other optical parameters such as extinction coefficient, Urbach energy, and optical conductivity have estimated using absorption spectra. All films show n-type conductivity, and it decreases with increasing Zn content due to decreasing carrier concentration.     

Data analytics in wireless systems and IoT issues and challenges

The emergence of data engineering along with the support of Online Social Networks is growing by millions every day due to the introduction of wireless systems and Internet of Things. The rapid growth of usage of smart devices helps to create new generation knowledge sharing platforms. Data Analytics has a major role to play in the growth and success of wireless and IoT applications. The growth of data has become exponential and is difficult to analyze. Many researchers depend on the data available on Wireless Systems and IoT for developing new generation services and applications. With the opportunity of information and communication technologies like heterogeneous networking, cloud computing, web services, crowd sensing and data mining, ubiquitous and asynchronous information sharing is feasible. But this also brings out a lot of provocations with respect to conflicting standards, data portability, data aggregation, data distribution, differential context and communication overhead. The smart information and communication technology has changed many features of human lifestyle: personal and work places.     

A rare case of Actinomyces skin and soft tissue infection in an end‐stage kidney disease patient with a review of the literature

End‐stage kidney disease (ESKD) patients are a commonly overlooked immunocompromised population that places them at risk for rare infections. We describe the case of a 78‐year‐old man with a history of ESKD managed with thrice weekly in‐center hemodialysis who had a prolonged episode of left elbow pain and drainage and was eventually found to have a skin and soft tissue infection from Actinomyces radingae. We review the bacteriology of Actinomyces spp. and the experiences of other providers who have treated actinomycosis in individuals with ESKD. The anatomic sites and demographics of these individuals are heterogeneous, but they all generally require a long antibiotic course with a beta‐lactam and portend to a good prognosis. High index of suspicion is needed to identify rare and atypical infections in the ESKD population.     

Performance Analysis of Multi User Mimo System With Successive Hybrid Information and Energy Transfer Beamformer

Wireless Personal Communications - Alzheimer’s Disease is a degenerative neurological disease that progresses slowly and gradually. Currently incurable, and those who suffer from it deprive...     

Effect of Shrinkage on Primary Dendrite Arm Spacing during Binary Al-Si Alloy Solidification

Upward and downward directional solidification of hypoeutectic Al-Si alloys were numerically simulated inside a cylindrical container. Undercooling of the liquidus temperature prior to the solidification event was introduced in the numerical model. The finite-volume method was used to solve the energy, concentration, momentum, and continuity equations. Temperature and liquid concentrations inside the mushy zone were coupled with local equilibrium assumptions. An energy equation was applied to determine the liquid fraction inside the mushy zone while considering the temperature undercooling at the solidifying dendrite/liquid interface. Momentum and continuity equations were coupled by the SIMPLE algorithm. Flow velocity distribution at various times, G, R, λ ₁, and solidification time at mushy zone/liquid interface during solidification were predicted. The effect of shrinkage during solidification on these solidification parameters was quantified. Transient temperature distribution, solidification time for the mushy zone/liquid interface, and λ ₁ were validated by laboratory experiments. It was found that better agreement could be achieved when the fluid flow due to solidification shrinkage was considered. Considering shrinkage in upward solidification was found to only have a marginal effect on solidification parameters, such as G, R, and λ ₁; whereas, in the downward solidification, fluid flow due to shrinkage had a significant effect on these solidification parameters. Considering shrinkage during downward solidification resulted in a smaller R, stronger fluid flow, and increased solidification time at the mushy zone/liquid interface. Further, the flow pattern was significantly altered when solidification shrinkage was considered in the simulation. The effect of shrinkage on G and λ ₁ strongly depended on the instantaneous location of the mushy zone/liquid interface in the computational domain. The numerical results could be validated by experimental data only when both the undercooling of the liquidus temperature prior to solidification and fluid flow in the liquid caused by the effect of shrinkage during solidification were included in the model.