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This is the first study on Red Palm Weevil Rhynchophorus ferrugineus (Oliv.) in Baharia Oases. The aim of the present work was to study the population abundance of R. ferrugineous (Oliv.) adults in relation to two climatic factors using attracting pheromone traps on date palm plantation. This work was carried out during January 2013 to December 2014 in Baharia Oases, Giza Governorate- Egypt. The obtained results recorded that adults emerging continually throughout the year. The lowest adults population was recorded during January and December in the two tested years, the population showed two peaks of adult population for each year. The first peak in 2013 recorded at the second week of April while the second peak recorded at second week of October. In 2014 the first peak recorded at second week of March and the second peak at the second week of September. There were different effects of daily mean temperature and relative humidityon the population activity of R. ferrugineous. The sex ratios of male to female were 1: 2.5 and 1: 2.4 during 2013 and 2014 respectively.

The present work investigates the influence of welding sequence and scheme on residual stresses induced during in-service sleeve repair welding of gas pipelines. For this purpose, a 3D thermo-mechanical FE analysis is conducted on an 8″-Schedule-20, API 5L-X65 steel pipe. Two welding sequences for the sleeve-pipe circumferential fillet welds are compared in the present study: sequential welding in which one side of the sleeve is welded first and then the other side is welded by the same welder, and simultaneous welding in which both sides of the sleeve are welded concurrently by two welders. Within the simultaneous welding sequence, four different welding schemes, designed to investigate the influence of the number of welders and welding directions on residual stresses, are investigated. The results show that the sequential welding sequence induces less residual stresses and distortions. Within the simultaneous welding sequence, the back-step welding scheme is found to induce the least average residual stresses as compared to other welding schemes.

Chicken infectious anemia virus (CIAV) is among the naturally occurring viruses that cause immunosuppression in chickens. In the present study, the impact of CIAV infection on both NDV vaccination immune responses and bird performance were demonstrated. Post CIAV infection, the mean live body weights of the ND-vaccinated groups showed improvement compared with the non-NDV vaccinated groups. The immunosuppressive effects of CIAV infection was higher and more obvious on live ND vaccinated group compared with the other vaccinated groups. The vaccination with combination of live and inactivated vaccines showed better HI-NDV Ab responses especially when inactivated vaccine was administrated at 9 days (group II). In consistent, both the phagocytic Percent and Index were lower in case of vaccination with live NDV vaccine only and CIAV infection. Birds were vaccinated with both live and inactivated NDV vaccines at different time points showed superior protection rate (100%) compared with the other groups. Microscopically, CIAV infection led to severe deterioration in the lymphoid tissues (thymus, bursa, spleen and bone marrow) such as focal to diffuse depletion of lymphocytes and hematopoietic cells. This study highlights the negative impact of CIAV infection on both bird performance and immune status.

Process capability indices such as C[subscript]p are used extensively in manufacturing industries to assess processes in order to decide about purchasing. In practice, the parameter for calculating C[subscript]p is rarely known and is frequently replace..

Recent research has shown that data mining models can accurately predict the outcome of a heart transplant based on predictors that include patient and donor's health/demographics. These models have not been adopted in practice, however, since they did not: a) consider the interactions between the explanatory variables; b) provide a patient's specific risk of survival (reported results have been primarily deterministic); and c) offer an automated decision tool that can provide some data-driven insights to practitioners. In this study, we attempt to overcome these three limitations through the use of Bayesian Belief Networks (BBN). The proposed BBN framework is comprised of four phases. In the first two phases, the data is preprocessed, and a candidate set of predictors is generated based on employing several variable selection methods. The third phase involves the addition of medically relevant variables to the list. In phase four, the BBN model is applied. The results show that the proposed BBN method provides similar predictive performance to the best approaches in the literature. More importantly, our method provides novel information on the interactions among the predictors and the conditional probability of survival for a given set of relevant donor-recipient characteristics. We offer U.S. practitioners a decision support tool that presents an individualized survival score based on our BBN model (and the UNOS dataset). A model that provides competitive predictors for 9-year heart transplantation outcomes.The BBN model presents data-driven insights into how the predictors interact.The result of the methodology is a novel individualized risk score for heart transplant outcomes.A decision support tool is provided to assist practitioners in characterizing a heart transplant's risk.

Understanding human behaviors has received considerable attention in neuroscience literature. Existing research addressed the main question: given measurements of a certain human movement, what is the underlying optimality criteria that human has optimized to fulfill this movement? Inverse Optimal Control (IOC) is a well-established approach to understand the biological movements in terms of the optimal control theory. IOC learns the criterion that best describes the demonstrated human behavior. Thus far, gradient-based techniques have been used to obtain the unknown behavior cost. However, these techniques are limited by locating only local optimum parameters. In this paper, behavior learning is modeled as an Inverse Linear Quadratic Regulator (ILQR) problem, where linear behavior dynamics and a quadratic cost are assumed. An efficient meta-heuristic technique, Particle Swarm Optimization (PSO), is used to retrieve the unknown cost in the proposed ILQR problem. Moreover, an evolving-ILQR algorithm is proposed to refine the learned cost once new unseen demonstrations exist to overcome the over-fitting problem. The reach-to-grasp behavior is studied to quantify the proposed approaches. Results are encouraging and show consistency with that in neuroscience literature. Meanwhile, the evolving-ILQR algorithm has quantified in successive scenarios, where the so far retrieved behavior cost has incrementally refined once new unseen demonstrations are available.

This study examines theoretically and computationally the non-Newtonian boundary layer flow and heat transfer for a viscoelastic fluid over a stretching continuous sheet embedded in a porous medium with variable fluid properties, slip velocity, and internal heat generation/absorption. The flow in boundary layer is considered to be generated solely by the stretching of the sheet adjacent to porous medium with boundary wall slip condition. Highly nonlinear momentum and thermal boundary layer equations governing the flow and heat transfer are reduced to set of nonlinear ordinary differential equations by appropriate transformation. The resulting ODEs are successfully solved numerically with the help of shooting method. Graphical results are shown for non-dimensional velocities and temperature. The effects of heat generation/absorption parameter, the porous parameter, the viscoelastic parameter, velocity slip parameter, variable thermal conductivity and the Prandtl number on the flow and temperature profiles are presented. Moreover, the local skin-friction coefficient and Nusselt number are presented. Comparison of numerical results is made with the earlier published results under limiting cases.

This paper is focused on the study of the viscous Powell-Eyring liquid thin film flow and heat transfer driven by an unsteady stretching sheet in the presence of slip velocity and non-uniform heat generation. A system of equations for momentum and thermal energy are reduced to a set of coupled non-linear ordinary differential equations with the aid of dimensionless transformation. The resulting seven-parameter problem has been solved numerically by using an efficient shooting technique coupled with the fourth-order Runge-Kutta algorithm over the entire range of physical parameters. To interpret various physical parameters governing the flow and heat transfer which appear in the momentum and energy equations, the results are presented graphically. The present results are compared with some of the earlier published work in some limiting cases and are found to be in an excellent agreement. This favorable comparison lends confidence in the numerical results to be reported in the present work. Furthermore, the effects of the parameters governing the thin film flow and heat transfer are examined and discussed through graphs and tables. Also, the values of the local skin-friction coefficient and the local Nusselt number for different values of physical parameters are presented through tables. Additionally, the obtained results for some particular cases of the present problem appear in good agreement with the literature review.

Newcastle disease (ND) is a highly devastating disease for the poultry industry as it causes high economic losses. In this present study, a DNA vaccine containing the F and HN surface antigens of a highly virulent Newcastle disease virus (NDV), NDV/1/Chicken/2005 (FJ939313), was successfully generated. Cell transfection test indicated that the vaccine expressed the F and HN genes in Hep-2 cells. The main objective of this study was to compare the extent of protection induced by DNA vaccination after homologous and heterologous NDV-challenge as determined by the amount of NDV shedding after challenge. NDV-antibody-negative chickens were vaccinated either once, twice or thrice intramuscularly at 7, 14 and 21 days old and were challenged 14 days post vaccination with either homologous virus (vaccine-matched velogenic viscerotropic Newcastle disease virus (vvNDV) strain, FJ939313), phylogenetically related to group VII, or a phylogenetically divergent heterologous virus (unmatched vvNDV strain, AY968809), which belongs to genogroup VI and shows 84.1% nucleotide similarity to the NDV-sequences of the DNA vaccine. Our data indicate that birds, which received a single dose of the DNA vaccine were poorly protected, and only 30-40% of these birds survived after challenge with high virus shedding titre. Multiple administration of the DNA vaccine induced high protection rates of 70-90% with reduced virus shedding compared to the non-vaccinated and challenged birds. Generally, homologous challenge led to reduced tracheal and cloacal shedding compared to the heterologous vvNDV strain. This study provides a promising approach for the control of ND in chickens using DNA vaccines, which are phylogenetically closely related to the circulating field strains.

This study discusses the water absorption behavior of three different types of nanocomposites. Silica, carbon and alumina nanoparticles are used as fillers incorporated in epoxy resin with different contents of 0.5, 1.5, and 3 wt%. A new nonlinear least-squares regression approach in conjunction with a gradient optimization was developed using symbolic manipulator MAPLE software to find the best fit. The equilibrium moisture content of the nanocomposites is measured as a function of time and the analytical modelling is successfully conducted. Results indicate that the addition of nanoparticles generally lower moisture content in contrast to neat epoxy. Compositions of 1.5 and 3 wt% alumina as well as silica nanocomposites however show a different behaviour. Diffusion coefficients for different types of nanocomposites were computed using Fickian and Langmuir models of diffusion. The least and highest diffusion coefficients correspond to the addition of silica 0.5 wt% and alumina 3 wt%, respectively.

Many places in the world are heavily contaminated with landmines, which cause that many resources are not utilized. This makes landmine detection and removal challenges for research. To guarantee reliable landmine sensing system, deep analysis and many test cases are required. The proposed concept is based on application of 1 kPa external constant pressure (lower than the landmine activation pressure) to the sand surface. The resultant contact pressure distribution is dependent on the imbedded object characteristics (type and depth). Then neural networks (NN) are trained to find the inverse solution of the sand–landmine problem. In other words, when the contact pressure is known, NN can estimate the imbedded object type and depth. In this work, using finite element modeling, the existence of landmines in sand is modeled and analyzed. The resultant contact pressure distribution for five objects (1—anti-tank, 2—anti-personnel, 3—can with diameter and height of 200 mm, 4—spherical rock with 200 mm diameter, and 5—sand without any object) in sand at different depths is used in training NN. Three NN are developed to estimate the landmine characteristics. The first one is perceptron type which classifies the introduced objects in sand. The other two feed-forward NN (FFNN) are developed to estimate the depth of two landmine types. The NN detection rates of anti-tank and anti-personnel landmines are 100 and 67 % in training, and 95 and 70 % in validation, respectively. As test cases, the detection rates of the NN in case of landmine inclination angles (0°–30°) are studied. The results show same detection rates as those at no inclination. A random noise 10 % of the average signal does not affect NN detection rates, which are the same as 95 and 70 % as in validation for anti-tank and anti-personnel, respectively, while with 20 % noise detection rates are decreases to 90 and 50 % for anti-tank and anti-personnel, respectively.

The increasing availability of high-volume, high-velocity data sets, often containing variables of dfferent data types, brings an increasing need for monitoring tools that are designed to handle these big data sets. While the research on multivariate st..

In this paper, a steady solution is presented for the equations that represent the MHD rarefied gas fluid flow and heat transfer due to a permeable stretching sheet with second-order velocity slip and thermal slip phenomenon. By using nondimensional transformations, the system of partial differential equations governing the problem is transformed into another system of nonlinear ordinary differential another equations. Novel solutions are investigated for the resulting ordinary differential equation which describe the momentum equation. The numerical results obtained agreed very well with previously reported cases available in the literature. Additionally, the effects of the magnetic parameter, first- and second-order velocity slip parameter, conductivity parameter, thermal slip parameter and the suction (injection) parameter on both the velocity and temperature profiles and on the local skin-friction coefficient are discussed and presented through tables and graphs.

The use of expert systems in optimizing and transforming human performance has been limited in practice due to the lack of understanding of how an individual’s performance deteriorates with fatigue accumulation, which can vary based on both the worker and the workplace conditions. As a first step toward realizing the human-centered approach to artificial intelligence and expert systems, this paper lays the foundation for a data analytic approach to managing fatigue in physically-demanding workplaces. The proposed framework capitalizes on continuously collected human performance data from wearable sensor technologies, and is centered around four distinct phases of fatigue: (a) detection, where machine learning methodologies are deployed to detect the occurrence of fatigue; (b) identification, where key features relating to the fatigue occurrence is to be identified; (c) diagnosis, where the fatigue mode is identified based on the knowledge generated in the previous two phases; and (d) recovery, where a suitable intervention is applied to return the worker to mitigate the detrimental effects of fatigue on the worker. Moreover, the framework establishes criteria for feature and machine learning algorithm selection for fatigue management. Two specific application cases of the framework, for two types of manufacturing-related tasks, are presented. Based on the proposed framework and a large number of test sets used in the two case studies, we have shown that: (i) only one wearable sensor is needed for fatigue detection with an average accuracy of ≥ 0.850 and a random forest model comprised of

The overarching goal of this paper is to develop a modeling framework that can be used to obtain personalized, data-driven and monotonically constrained probability curves. This research is motivated by the important problem of improving the predictions for organ transplantation outcomes, which can inform updates made to organ allocation protocols, post-transplantation care pathways, and clinical resource utilization. In pursuit of our overarching goal and motivating problem, we propose a novel two-stage machine learning-based framework for obtaining monotonic probabilities over time. The first stage uses the standard approach of using independent machine learning models to predict transplantation outcomes for each time-period of interest. In the second stage, we calibrate the survival probabilities over time using isotonic regression. To show the utility of our framework, we applied it on a national registry of U.S. heart transplants from 1987 to 2016. The first stage produces an area under the receiver operating curve (AUC) between 0.60 and 0.71 for years 1–10. While the 1-year prediction AUC result is comparable to the reported results in the literature, our 10-year AUC of 0.70 is higher than the current state-of-the-art results. More importantly, we show that the application of isotonic regression to calibrate the survival probabilities for each patient over the 10-year period guarantees monotonicity, while capitalizing on the data-driven and individualized nature of machine learning models. To promote future research, our code and analysis are publicly available on GitHub. Furthermore, we created a web app titled “H-TOP: Heart Transplantation Outcome Predictor” to encourage practical applications.

In recent years, the use of bio-fibers to replace synthetic fibers in composites has gained popularity due to increasing environmental concerns and requirements for developing sustainable materials for engineering applications. The objective of this study is to minimize the weight and cost of a symmetric laminated composite beam with a specified lower bound constraint on its natural frequency. The optimal design of hybrid composite beams with different boundary conditions was considered. The optimization problem accounts for fiber type, fiber volume fractions, thickness, and fiber orientation angles of different layers as design variables. The optimum design of the hybrid carbon/flax/epoxy laminated beam for different values of frequency lower limits was computed and compared with those of the hybrid carbon/glass/epoxy, neat glass/epoxy, and neat flax/epoxy laminated beams. Results showed that hybridization between the carbon fiber and flax fiber results in the best designs with the advantages of a lightweight, low cost and higher fundamental frequencies.

The coronavirus disease 2019 (COVID-19) pandemic has exposed many issues within the global value chains and caught many companies with their guard down during the early stages of their digital transformation Several COVID-19 mitigation measures, such as travel restrictions, social distancing, and remote work were quickly introduced, and many manufacturing companies have struggled to keep their factories operational As a result, smart technologies, such as artificial intelligence and wearables, have been rapidly deployed on the shop floor to mitigate the COVID-19 impact with the short-term objective of keeping the workforce safe and the facilities compliant with the requirements to remain open The majority of these newly introduced and rapidly deployed smart systems carry a significant price tag This paper explores the impacts of this rapid adoption of smart technologies with regard to the workforce’s role in smart manufacturing systems during and post–COVID-19 Furthermore, we attempt to provide initial insights to the question: “what is the long-term impact and value of these rapidly deployed and sophisticated smart technologies in the post–COVID-19 Smart Manufacturing Systems” Copyright © 2020 by ASTM International

Pipe bends are critical components in piping systems where their failure modes are quite different from straight pipes. The objective of the present work is to investigate the limit loads of pipe bends with actual As-fabricated shape obtained from pipe bending process as compared to bends with Ideal and Assumed imperfect shapes. The present work is conducted by using nonlinear finite element analysis and is performed in two steps. The first step is achieved by simulating rotary pipe bending process with ball mandrel to obtain the actual as-fabricated shape of the 90° pipe bend. The process simulation was verified against published experimental data. In the second step, the pipe bend is subjected to different combinations of simultaneous loads consisting of internal pressure and In-plane closing bending moment. Results are provided for limit load curves for pipe bends with as-fabricated geometries and bends with ideal shape and assumed geometrical imperfections.

This work will scrutinize the flow of non-Newtonian Sisko fluid owing to a nonlinearly stretching sheet. The mingle effect of viscous dissipation and non-uniform heat generation are also supposed in this work. In our work, we contribute toward gaining the similar solution for our problem. Eventually, the group of equations controlling the problem is reduced to a couple of characteristic equations, the first represents the momentum whereas the second is the energy equation. Shooting method is then applied further to get the numerical solution for this yielded set of equations. Also, this proposed model may enable us to evaluate both the skin friction coefficient and the Nusselt number. Finally, our proposed research agrees very well with related works.

This research attempts to draw a fuller understanding of the magnetohydrodynamic flow of Williamson fluid owing to a continuously moving permeable surface. A detailed illustration of the importance of the effects of viscous dissipation and the variable fluid properties phenomena are also given. Meanwhile, this work has also revived the interest of the slip velocity phenomenon. The success is met after formulating the thorough equations which describe this model, thus it is no longer difficult to get into the numerical solution for this model via the shooting method. By analogy, this interesting subject also stimulates us to pursue further details which can be obtained from both the drag force or the skin-friction coefficient and the rate of heat transfer. Based on our apparent results, the presence of magnetic field, suction phenomena and slip velocity was the reason to reduce the surface velocity. Also, the same parameters can serve as a helpful guide for governing the rate of heat transfer.

This research paper is concerned with the mechanical behavior of the cylindrical vessels with hillside nozzles when subjected to both pressure and nozzle bending loads in cyclic forms. The influence of hillside angle on shakedown (SD) limits of the connection under cyclic pressure and combined steady pressure with cyclic nozzle bending is investigated. A shell finite element analysis model is built for the assembly using five different hillside angles ranging from 0 deg to 40 deg. Shakedown limits are determined by a direct technique known as the nonlinear superposition method (NSM). Bree diagrams for cyclic out of plane opening (OPO)/in plane (IP) nozzle moments combined with steady internal pressure are determined. The results show an increase in both OPO and IP shakedown moments as the hillside angle is increased. In addition, the OPO shakedown limit moments for all hillside angles were found to be insensitive to the level of internal pressure; this differs from the IP shakedown moment which starts to decrease with pressure for the high pressures.

Lichenoid drug reactions are rare compared to typical morbilliform drug exanthema or urticaria. They are associated with specific drugs or drug families like gold, antimalarial drugs, β‑blockers and angiotensin-converting-enzyme inhibitors. Recent observations included associations with novel drugs such as biologics (e. g. tumour necrosis factor antagonists) and immune checkpoint inhibitors (anti-programme cell death protein 1 antibodies). Lichenoid drug reactions most often resemble lichen planus mainly in areas of ultraviolet-light exposed skin, but also mucosal lichen planus and even bullous lesions may occur.

While many large touchscreen devices have a split keyboard option to enable two-thumb typing, there are significant differences in the design which affect users’ text entry rate. A mixed-integer programming model is developed to optimize key-to-thumb assignment with the objective of minimizing the expected time to type a character. Computer simulations are conducted to determine the optimal key dimension under different values of the Fitts’ law’s slope coefficient, typing error rate, and alternate-hand advantage phenomenon. The results show that text entry rate and the optimal key-to-thumb assignment depend on key dimensions, user’s speed-accuracy profile, and the level of alternate-hand advantage. The optimal keyboard is proposed. To validate the analytical findings, an empirical study is conducted with eighteen users and six different keyboards in terms of key dimensions and typing zone. Empirical results report between 7% and 18% improvement in the text entry rate over the other split keyboards tested.

This article is devoted to describe the boundary layer flow and heat transfer for non-Newtonian Powell–Eyring fluid over an exponentially stretching continuous impermeable surface with an exponential temperature distribution taking into account variable thermal conductivity. The fluid thermal conductivity is assumed to vary as a linear function of temperature . The governing partial differential equations are transformed into a set of coupled non-linear ordinary differential equations and then solved with numerical technique using appropriate boundary conditions for various physical parameters . The numerical solution for the governing non-linear boundary value problem is based on applying Chebyshev spectral method over the entire range of physical parameters. The effects of governing parameters like the thermal conductivity parameter and the Prandtl number on the flow and temperature profiles as well as on the local skin-friction coefficient and the local Nusselt number are computed and discussed through graphs and tables. In this work, a special attention is given to investigate the effect of the variable thermal conductivity parameter on the temperature field above the stretching sheet.

In this paper, we introduce a theoretical and numerical study for the effects of thermal buoyancy and constant heat flux on the Casson fluid flow and heat transfer over an exponentially stretching sheet taking into account the effects of variable thermal conductivity, heat generation/absorption and viscous dissipation. The governing partial differential equations are transformed into coupled, non-linear ordinary differential equations by using suitable transformations. Numerical solutions to these equations are obtained by using the fourth order Runge-Kutta method with the shooting technique. The effects of various physical parameters which governing the flow and heat treansfer such as the buoyancy parameter, the thermal conductivity parameter, heat generation or absorption parameter and the Prandtl number on velocity and temperature are discussed by using graphical approach. Moreover, numerical results indicate that the local skin-friction coefficient and the local Nusselt number are strongly affected by the constant heat flux.

The current research utilizes a direct non-cyclic technique to generate elastic shakedown domains for thinned-wall 90° elbows. The elbows are subjected to simultaneous steady internal pressures and cyclic in-plane and out-of-plane bending moments. Wall thinning is located at the intrados, extrados, and crown once at a time. Effects of thinning depth and thinning location under both cyclic in-plane and out-of-plane bending modes are investigated. Generated shakedown boundaries are compared to those corresponding to sound elbows. Elbows subjected to out-of-plane bending moments revealed relatively higher shakedown domains compared to corresponding elbows subjected to in-plane bending. It is generally noticed that thinning at the intrados or crown has more severe effect on reducing elbows shakedown domains as compared to thinning at the extrados for both in-plane and out-of-plane bending modes.

Image-capturing systems are increasingly being used in manufacturing shop floors since they can reliably capture important aesthetic information pertaining to the quality of manufactured parts in real time. State-of-the-art image-monitoring applications have focused on the detection of a single fault; however, the number of fault clusters per image in industrial applications can be numerous. To address this issue, we propose the use of a multivariate generalized likelihood ratio (MGLR) control chart for monitoring industrial products whose quality is described by a specific pattern (e.g. uniform patterns in LED screens or decorative patterns in textile products). Our method is specifically designed for greyscale images that are typical outputs of real-time industrial image-capturing systems. Extensive computer simulations show that the proposed method can detect the occurrence of single and multiple faults. We also present an experimental study to highlight how practitioners can implement and make use of ...

An ongoing, two-fold challenge involves extracting useful information from the massive amounts of highway crash data and explaining complicated statistical models to inform the public about highway safety. Highway safety is critical to the trucking industry and highway funding policy. One method to analyze complex data is through the application of visual data mining tools. In this paper, we address the following three questions: a) what existing data visualization tools can assist with highway safety theory development and in policy-making?; b) can visual data mining uncover unknown relationships to inform the development of theory or practice? and c) can a data visualization toolkit be developed to assist the stakeholders in understanding the impact of publicpolicy on transportation safety? To address these questions, we developed a visual data mining toolkit that allows for understanding safety datasets and evaluating the effectiveness of safety policies.

This study presents the root cause analysis of a weldment failure in a thermowell assembly operating in a natural gas processing plant. Laboratory investigations indicated inferior quality for the fillet weld joining the thermowell flange to the pipe supporting the thermowell to the main pipe. The fillet weld exhibited excessive concavity, lack of penetration and lack of fusion. This led to minute weldment cracking, which was exacerbated by flow-induced vibrations exceeding safe operational limits. This promoted small magnitude, high frequency stress cycling coupled with high mean stress at the poorly welded joint, which led to accumulation of high cycle fatigue damage and final fracture causing gas leakage. Mitigation plans included use of a shorter support pipe and revised safe operational envelope of the pipeline under consideration.

This paper is focused on the study for the effects of constant heat flux and thermal buoyancy on the steady two-dimensional flow and heat transfer of a non-Newtonian power-law fluid over a non-linearly stretching vertical surface in the presence of thermal radiation. Highly nonlinear momentum and thermal boundary layer equations which governing the flow and heat transfer are reduced to a set of nonlinear ordinary differential equations by appropriate transformation. The resulting ODEs are successfully solved numerically with the help of fourth order Runge–Kutta method coupled with the shooting technique. The effects of various parameters like the buoyancy (mixed convection) parameter, the radiation parameter, power-law index parameter and the local Prandtl number on the flow and temperature profiles as well as on the local skin-friction coefficient and the local Nusselt number are presented and discussed. Favorable comparisons of numerical results with previously published work on various special cases of the problem are obtained.

An analysis was carried out to describe the problem of flow and heat transfer of Powell–Eyring fluid in boundary layers on an exponentially stretching continuous permeable surface with an exponential temperature distribution in the presence of heat flux and variable thermal conductivity. The governing partial differential equations describing the problem were transformed into a set of coupled non-linear ordinary differential equations and then solved with a numerical technique using appropriate boundary conditions for various physical parameters. The numerical solution for the governing non-linear boundary value problem is based on applying the shooting method over the entire range of physical parameters. The effects of various parameters like the thermal conductivity parameter, suction parameter, dimensionless Powell–Eyring parameters and the Prandtl number on the flow and temperature profiles as well as on the local skin-friction coefficient and the local Nusselt number are presented and discussed. In this work, special attention was given to investigate the effect of the thermal conductivity parameter on the velocity and temperature fields above the sheet in the presence of heat flux. The numerical results were also validated with results from a previously published work on various special cases of the problem, and good agreements were seen.

The main aim of this article is to introduce the approximate solution for MHD flow of an electrically conducting Newtonian fluid over an impermeable stretching sheet with a power law surface velocity and variable thickness in the presence of thermal-radiation and internal heat generation/absorption. The flow is caused by the non-linear stretching of a sheet. Thermal conductivity of the fluid is assumed to vary linearly with temperature. The obtaining PDEs are transformed into non-linear system of ODEs using suitable boundary conditions for various physical parameters. We use the Chebyshev spectral method to solve numerically the resulting system of ODEs. We present the effects of more parameters in the proposed model, such as the magnetic parameter, the wall thickness parameter, the radiation parameter, the thermal conductivity parameter and the Prandtl number on the flow and temperature profiles are presented, moreover, the local skin-friction and Nusselt numbers. A comparison of obtained numerical results is made with previously published results in some special cases, and excellent agreement is noted. The obtained numerical results confirm that the introduced technique is powerful mathematical tool and it can be implemented to a wide class of non-linear systems appearing in more branches in science and engineering.

As measurement technologies evolve, our ability to detect, isolate and diagnose process faults on the shop-floor is rapidly changing. Three dimensional scanners provide the opportunity to capture the entire surface geometry of a manufactured part and allow for the detection of a wide variety of fault patterns that may not be captured by traditional measurement devices. Despite their advantages, their use in practice is limited due to the complexities associated with the analysis of 3D laser scan data (point clouds). Therefore, the objective of our work is to allow practitioners to fully utilize the inherent advantages of point clouds by providing a framework that can facilitate their analysis and visualization. More specifically, we transform point clouds into 2D images (without the loss of any spatial information) to benefit from the image analysis and monitoring techniques that are currently being implemented on the shop-floor. We provide numerical and experimental examples to illustrate and validate the advantages of our proposed method. Finally, we offer advice to practitioners and recommendations for future research.

Predatory potential of Chrysoperla carnea (Stephens) was studied on different larval instars of Phyllocnistis citrella (i.e. second, third and mixture of all larval instars) under laboratory conditions (26± 2oC, 65±5% R.H, 16:8 L: D photo period). Results revealed that feeding and rearing on different larval instars of P. citrella affected predator biology with different degrees. It had no significant effect on incubation period of C. carnea eggs females, pupation period, adult longevity and pre-and post - oviposition periods. On the other hand, it had significant effect on C. carnea larval period and its survival, female fecundity and eggs fertility. In general, third instar larvae of P. citrella was the most preferred prey for C. carnea. The results illustrate the potential importance of prey resources (life stage) on C. carnea population growth and indicate that C. carnea has considerable potential for the biological control of P. citrella.

This research paper is concerned with the mechanical behavior of the cylindrical vessels with hillside nozzles when subjected to both pressure and nozzle bending loads in cyclic forms. The influence of hillside angle on shakedown (SD) limits of the connection under cyclic pressure and combined steady pressure with cyclic nozzle bending is investigated. A shell FEA model is built for the assembly using five different hillside angles ranging from 0° to 40°. Shakedown limits are determined by a direct technique known as the Nonlinear Superposition Method (NSM). Bree diagrams for cyclic out of plane opening (OPO) / in plane (IP) nozzle moments combined with steady internal pressure are determined. The results show an increase in both OPO and IP shakedown moments as the hillside angle is increased. In addition, the OPO shakedown limit moments for all hillside angles was found to be insensitive to the level of internal pressure in contrary to IP shakedown moment which starts to reduce with pressure for the high pressure range.

This article presents a numerical solution for the flow of a Newtonian fluid over an impermeable stretching sheet embedded in a porous medium with the power law surface velocity and variable thickness in the presence of thermal radiation. The flow is caused by non-linear stretching of a sheet. Thermal conductivity of the fluid is assumed to vary linearly with temperature. The governing partial differential equations (PDEs) are transformed into a system of coupled non-linear ordinary differential equations (ODEs) with appropriate boundary conditions for various physical parameters. The remaining system of ODEs is solved numerically using a differential transformation method (DTM). The effects of the porous parameter, the wall thickness parameter, the radiation parameter, the thermal conductivity parameter, and the Prandtl number on the flow and temperature profiles are presented. Moreover, the local skin-friction and the Nusselt numbers are presented. Comparison of the obtained numerical results is made with previously published results in some special cases, with good agreement. The results obtained in this paper confirm the idea that DTM is a powerful mathematical tool and can be applied to a large class of linear and non-linear problems in different fields of science and engineering.

This study presents a comparative evaluation of the various acceptance criteria in API579-ASME/1 fitness-for-service (FFS) code for equipment suffering from metal loss, using a case of severe corrosion in a pipe subjected to internal pressure and supplemental loads. All three assessment levels were conducted to evaluate the remaining life of the pipe under various acceptance criteria assuming constant corrosion rate. In particular, Level-3 assessment was performed using three-dimensional parametric limit finite element analysis to evaluate the remaining life. The model accounts for the observed metal loss, with the aim of evaluating the plastic collapse pressure of the corroded pipe. The remaining life was estimated using both global and local failure criteria and the conservatism of various methods and criteria is assessed. Results showed a potential trade-off of continued operation at the original design pressure for shorter period against a pressure de-rating procedure for extended operation.

This article investigates a theoretical and numerical study for the effect of viscous dissipation on the steady flow with heat transfer of Newtonian fluid toward a permeable stretching surface embedded in a porous medium with a second-order slip and thermal slip. The governing nonlinear partial differential equations are converted into nonlinear ordinary differential equations (ODEs) using similarity variables. The resulting ODEs are successfully solved numerically with the help of Chebyshev finite difference method. Graphically results are shown for non-dimensional velocities and temperature. The effects of the porous parameter, the suction (injection) parameter, Eckert number, first- and second-order velocity slip parameter, the thermal slip parameter and the Prandtl number on the flow and temperature profiles are presented. Moreover, the local skin-friction and Nusselt numbers are presented. A comparison of numerical results is made with the earlier published results under limiting cases.

Statistical process control (SPC) is a collection of problem-solving tools used to achieve process stability and improve process capability through variation reduction. Because of its sound statistical basis and intuitive use of visual displays, SPC has been extensively used in manufacturing and health care and service industries. Deploying SPC involves both a technical aspect and a proper environment for continuous improvement activities based on management support and worker empowerment. Many of the commonly used SPC tools, including histograms, fishbone diagrams, scatter plots, and defect concentration diagrams, were proposed prior to the advent of microcomputers as efficient methods to record and visualize data for single (or few) variable(s) processes. As the volume, variety, and velocity of data continues to evolve, there are opportunities to supplement and improve these methods for understanding and visualizing process variation. In this paper, we propose enhancements to some of the basic quality tools that can be easily applied with a desktop computer. We demonstrate how these updated tools can be used to better characterize, understand, and/or diagnose variation in a case study involving a US manufacturer of structural tubular metal products. Finally, we create the quality visualization toolkit to allow practitioners to implement some of these visualization tools without the need for training, extensive statistical background, and/or specialized statistical software. Copyright © 2014 John Wiley & Sons, Ltd.

A numerical study has been carried out to analyze the constant heat flux, internal heat generation, variable viscosity and thermal radiation effects on the flow and heat transfer of a Newtonian fluid over an exponentially stretching porous sheet. Using a similarity transformation, the governing partial differential equations are transformed into coupled, non-linear ordinary differential equations with variable coefficients. Numerical solutions to these equations subject to appropriate boundary conditions are obtained by using an efficient Chebyshev spectral method. The effects of various physical parameters such as viscosity parameter, the suction parameter, the radiation parameter, internal heat generation or absorption parameter and the Prandtl number on velocity and temperature are discussed by using graphical approach. Moreover, numerical results indicate that in the presence of constant heat flux, the skin-friction coefficient as well as Nusselt number is strongly affected by the viscosity parameter, suction parameter, radiation parameter and the internal heat generation parameter.

Egypt is one of the top ten countries realizing feasible Sugar beet yield (21ton/fed).Similarly Egypt occupies the eleventh rank in producing Sugar cane with an average production 48.89 ton/fed during 2011. Sugar beet is considered as the alternative of Sugar cane in providing local consumption of Sugar. This study aimed at investigating the effect of introducing mechanical technology in performing agricultural field operations of Sugar beet production. The study mainly depended on the recent available data and field questionnaire (Bannie Soief), governorate was selected based on the Sugar beet cultivated area 27284 feddans and especially in Elwasta district where about 2055 feddans are cultivated with Sugar beet. The analysis of the obtained data indicted that the Sugar beet cultivated area changes annually by 1.01% of the main average while the total yield changes annually by 10.5 % of the average yield production. The field study investigated 6 systems of mechanizing field operations where samples ranged between 21 and only one sample for each system. Three of these systems were excluded and the economic analysis covered only three. The one directional variance analysis revealed that the differences at confidence level 95% was insignificant. The evaluation of productivity based on risk assured the highly degree of variance that ranged between 18.37-25.65 % which reflected the farmer's behavior towards mechanizing the field operations due to their midget area. The economic parameters pointed that the second system realized net return less than the third system which applied mechanical spraying instead of the manual application. Generally the rest of the investigated economic parameters justified the superiority of the third system which leads to recommend its adoption by Sugar beet growers. Neverseles, in order to reinforce this recommendation, further deep studies must be applied on large scale areas which enable to apply different levels of mechanizination.

This paper describes and evaluates the use of the Absolute Nodal Coordinate Formulation (ANCF) in modeling large size wind turbine blades. Modern blade model can be divided into two regions classified by aerodynamic and structural function. The aerodynamic region, blade-span, is utilizing the thinnest possible airfoil section. On the other hand, the transition between the circular mount and the first airfoil profile is referred as blade-root region, which carries highest loads along the blade. In this investigation, an efficient procedure is developed for mapping NACA airfoil wind-turbine blades into ANCF thin plate models. The procedure concerns a complete wind turbine blade structure, blade-root as well as the blade-span regions with non-uniform and twisted nature. As a result, the slope discontinuity problem arises in both chord-wise and span-wise directions, and consequently presents numerical errors in dynamic simulation. The paper investigates the methods of modeling slope discontinuity resulting from the variations of the cross-sectional layouts across the blade. The developed method is applied for the gradient-deficient thin plate element in order to account for structural discontinuity. In addition, the aerodynamic loads are precisely expressed and the aerodynamic characteristics of such blades are examined with the ANCF and with the classical finite element method. The static and dynamic solutions of different operating conditions are obtained and results are compared with those obtained using ANSYS code. Both the limitations and advantages of using the ANCF in modeling large size wind turbine blades are concluded and discussed. A Dynamics for Design (DFD) procedure is presented with numerical example concerning large-rotation, large deformation wind turbine blades.

SUMMARYThis paper studies the effect of joint flexibility on the dynamic performance of a serial spatial robot arm of rigid links. Three models are developed in this paper. The first and the third models are developed using the multibody dynamics approach, while the second using the classical robotics approach. A numerical algorithm and an experimental test-rig are developed to test the final model. The links' inertial parameters are estimated numerically. Empirical formulae with assumption models are used to estimate the flexibility coefficients. The simulation results show that the joint damping is a major source of inaccuracies, causing trajectory error without a proper feedback controller.

The unsteady laminar magnetohydrodynamic flow over an unsteady stretching sheet in the presence of thermal radiation and variable heat flux is investigated. The governing time-dependent boundary layer equations are transformed into ordinary differential equations containing a radiation parameter, space index parameter, time index parameter, Prandtl number, magnetic parameter, and unsteadiness parameter. These equations are solved numerically by applying the Chebyshev spectral method. The velocity profiles, temperature profiles, the skin friction coefficient, and the dimensionless surface temperature are computed and discussed in detail for various values of the different parameters. It is found that increasing the unsteadiness parameter leads to a fall for both the velocity and temperature distribution. Moreover, the temperature increases with the magnetic parameter, but the reverse is true for the velocity distribution. Likewise, the temperature decreases for increasing both values of space index parameter and time index parameter.

This paper presents a 12-Gb/s power-efficient voltage-mode driver for multi-standard serial-link applications. The proposed driver combines the advantages of voltage-mode drivers and those of variable-output-swing ones into a single architecture for multi-standard operation. This is achieved by having a reconfigurable pull-up network and a fixed shared pull-down network. In addition, this technique is combined with a modified 3-tap feed-forward equalizer (FFE) to support the de-emphasis required by several standards. The proposed driver is implemented using 65-nm CMOS technology and supports a variable output voltage swing of 0.3 Vpp to 1 Vpp, while achieving data rates ranging from 1.5 Gb/s to 12 Gb/s. The driver consumes 1.25 mW for an output swing of 0.5 Vpp, which is the minimum achievable power consumption for voltage-mode drivers.

Unexploded Landmines, after wares, represent a serious problem, wastes life and money. Recent research states that contact sensors are promising. In this work, a novel contact sensor for landmine detection is presented. The sensor principle is based on the concept of 2-DOF vibration absorber system (two springs and two masses), to detect the presence of an object (landmine) in sand which is modeled as a third spring. The 3rd spring stiffness (the sand stiffness) can be measured as a function of the vibration absorber frequency ω Abs (the frequency at which the 2nd mass gives minimum amplitude (theoretically proven: zero)) and the 1st mass gives amplitude near to peak. When the sand stiffness changes due to existence of the landmine, the vibration absorber frequency ω Abs changes, and consequently the landmine can be detected. The mathematical proof of the idea is verified by simulation on Matlab and finite element COMSOL Multi-physics. The system parameters are chosen to be appropriate with the sand-landmine stiffness measurement range. The simulation results are optimized to give best sensitivity and linearity of the sensor output. The sensor gives sensitivity of 1559 Hz/(MN/m) and linearity better than 95%. Finally, a detailed design procedure for the contact stiffness sensor for landmine detection is developed.