bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of Biohybrid Magnetite Nanoparticles and Moroccan Propolis on Adherence of Methicillin Resistant Strains of Staphylococcus aureus
Authors: El-Guendouz Soukaina , Aazza Smail , Lyoussi Badiaa , Bankova Vassya , Lourenço João , Costa Ana , Mariano José , Miguel Maria , Faleiro Maria
Published: September 2016

Biofilm bacteria are more resistant to antibiotics than planktonic cells. Propolis possesses antimicrobial activity. Generally, nanoparticles containing heavy metals possess antimicrobial and antibiofilm properties. In this study, the ability of adherence of Methicillin Resistant Strains of Staphylococcus aureus (MRSA) to catheters treated with magnetite nanoparticles (MNPs), produced by three methods and functionalized with oleic acid and a hydro-alcoholic extract of propolis from Morocco, was evaluated. The chemical composition of propolis was established by gas chromatography mass spectrometry (GC-MS), and the fabricated nanostructures characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Mossbauer spectroscopy and Fourrier transform infrared spectroscopy (FTIR). The capacity for impairing biofilm formation was dependent on the strain, as well as on the mode of production of MNPs. The co-precipitation method of MNPs fabrication using Fe3+ and Na2SO3 solution and functionalized with oleic acid and propolis was the most effective in the impairment of adherence of all MRSA strains to catheters (p < 0.001). The adherence of the strain MRSA16 was also significantly lower (p < 0.001) when the catheters were treated with the hybrid MNPs with oleic acid produced by a hydrothermal method. The anti-MRSA observed can be attributed to the presence of benzyl caffeate, pinocembrin, galangin, and isocupressic acid in propolis extract, along with MNPs. However, for MRSA16, the impairment of its adherence on catheters may only be attributed to the hybrid MNPs with oleic acid, since very small amount, if any at all of propolis compounds were added to the MNPs.
Stretching a Semiflexible Polymer in a Tube
Authors: Li Runhua , Wang Jizeng
Published: September 2016

How the statistical behavior of semiflexible polymer chains may be affected by force stretching and tube confinement is a classical unsolved problem in polymer physics. Based on the Odijk deflection theory and normal mode decomposition in terms of Fourier expansion, we have derived a new compact formula for the extension of a wormlike chain of finite length strongly confined in a tube and simultaneously stretched by an external force. We have also suggested a new deflection length, which together with the force-extension relation is valid for a very extended range of the tube-diameter/persistence-length ratio comparing to the classic Odijk theory. The newly derived formula has no adjustable fitting parameters for the whole deflection regime; in contrast, the classic Odijk length needs different prefactors to fit the free energy and average extension, respectively. Brownian dynamics simulations based on the Generalized Bead-Rod (GBR) model were extensively performed, which justified the theoretical predictions.
Detecting Slope and Urban Potential Unstable Areas by Means of Multi-Platform Remote Sensing Techniques: The Volterra (Italy) Case Study
Authors: Nolesini Teresa , Frodella William , Bianchini Silvia , Casagli Nicola
Published: September 2016

Volterra (Central Italy) is a town of great historical interest, due to its vast and well-preserved cultural heritage, including a 2.6 km long Etruscan-medieval wall enclosure representing one of the most important elements. Volterra is located on a clayey hilltop prone to landsliding, soil erosion, therefore the town is subject to structural deterioration. During 2014, two impressive collapses occurred on the wall enclosure in the southwestern urban sector. Following these events, a monitoring campaign was carried out by means of remote sensing techniques, such as space-borne (PS-InSAR) and ground-based (GB-InSAR) radar interferometry, in order to analyze the displacements occurring both in the urban area and the surrounding slopes, and therefore to detect possible critical sectors with respect to instability phenomena. Infrared thermography (IRT) was also applied with the aim of detecting possible criticalities on the wall-enclosure, with special regards to moisture and seepage areas. PS-InSAR data allowed a stability back-monitoring on the area, revealing 19 active clusters displaying ground velocity higher than 10 mm/year in the period 2011–2015. The GB-InSAR system detected an acceleration up to 1.7 mm/h in near-real time as the March 2014 failure precursor. The IRT technique, employed on a double survey campaign, in both dry and rainy conditions, permitted to acquire 65 thermograms covering 23 sectors of the town wall, highlighting four thermal anomalies. The outcomes of this work demonstrate the usefulness of different remote sensing technologies for deriving information in risk prevention and management, and the importance of choosing the appropriate technology depending on the target, time sampling and investigation scale. In this paper, the use of a multi-platform remote sensing system permitted technical support of the local authorities and conservators, providing a comprehensive overview of the Volterra site, its cultural heritage and landscape, both in near-real time and back-analysis and at different scales of investigation.
Distributed Particle Filter for Target Tracking: With Reduced Sensor Communications
Authors: Ghirmai Tadesse
Published: September 2016

For efficient and accurate estimation of the location of objects, a network of sensors can be used to detect and track targets in a distributed manner. In nonlinear and/or non-Gaussian dynamic models, distributed particle filtering methods are commonly applied to develop target tracking algorithms. An important consideration in developing a distributed particle filtering algorithm in wireless sensor networks is reducing the size of data exchanged among the sensors because of power and bandwidth constraints. In this paper, we propose a distributed particle filtering algorithm with the objective of reducing the overhead data that is communicated among the sensors. In our algorithm, the sensors exchange information to collaboratively compute the global likelihood function that encompasses the contribution of the measurements towards building the global posterior density of the unknown location parameters. Each sensor, using its own measurement, computes its local likelihood function and approximates it using a Gaussian function. The sensors then propagate only the mean and the covariance of their approximated likelihood functions to other sensors, reducing the communication overhead. The global likelihood function is computed collaboratively from the parameters of the local likelihood functions using an average consensus filter or a forward-backward propagation information exchange strategy.
Drift Reduction in Pedestrian Navigation System by Exploiting Motion Constraints and Magnetic Field
Authors: Ilyas Muhammad , Cho Kuk , Baeg Seung-Ho , Park Sangdeok
Published: September 2016

Pedestrian navigation systems (PNS) using foot-mounted MEMS inertial sensors use zero-velocity updates (ZUPTs) to reduce drift in navigation solutions and estimate inertial sensor errors. However, it is well known that ZUPTs cannot reduce all errors, especially as heading error is not observable. Hence, the position estimates tend to drift and even cyclic ZUPTs are applied in updated steps of the Extended Kalman Filter (EKF). This urges the use of other motion constraints for pedestrian gait and any other valuable heading reduction information that is available. In this paper, we exploit two more motion constraints scenarios of pedestrian gait: (1) walking along straight paths; (2) standing still for a long time. It is observed that these motion constraints (called “virtual sensor”), though considerably reducing drift in PNS, still need an absolute heading reference. One common absolute heading estimation sensor is the magnetometer, which senses the Earth’s magnetic field and, hence, the true heading angle can be calculated. However, magnetometers are susceptible to magnetic distortions, especially in indoor environments. In this work, an algorithm, called magnetic anomaly detection (MAD) and compensation is designed by incorporating only healthy magnetometer data in the EKF updating step, to reduce drift in zero-velocity updated INS. Experiments are conducted in GPS-denied and magnetically distorted environments to validate the proposed algorithms.
A Study of LoRa: Long Range & Low Power Networks for the Internet of Things
Authors: Augustin Aloÿs , Yi Jiazi , Clausen Thomas , Townsley William
Published: September 2016

LoRa is a long-range, low-power, low-bitrate, wireless telecommunications system, promoted as an infrastructure solution for the Internet of Things: end-devices use LoRa across a single wireless hop to communicate to gateway(s), connected to the Internet and which act as transparent bridges and relay messages between these end-devices and a central network server. This paper provides an overview of LoRa and an in-depth analysis of its functional components. The physical and data link layer performance is evaluated by field tests and simulations. Based on the analysis and evaluations, some possible solutions for performance enhancements are proposed.
The Provision of Powered Mobility Devices in Italy: Linking Process with Outcomes
Authors: Desideri Lorenzo , Trioschi Devis , Agusto Roberta , Bizzarri Martina , Spagnolin Gianantonio , Cantelli Sabrina , Paolini Caterina , Malavasi Massimiliano , Bitelli Claudio
Published: September 2016

The present paper reports on a series of studies conducted at the Regional Center for Assistive Technology (Centro Regionale Ausili, CRA) in Bologna, Italy. Our purpose was to identify a set of internationally validated instruments and a training circuit with a view to developing a structured and validated Powered Mobility Device (PMD) assessment and training program. To develop the program, three studies were conducted in order to identify: validated measures for assessing the user’s driving skills and training needs for using a PMD (Study 1); measures for evaluating the outcomes of the PMD (Study 2); and, the elements necessary for building a circuit for conducting PMD training (Study 3). In studies 1 and 2, the Wheelchair Skill Test 4.2 Power Wheelchair (WST) and the Wheelchair Outcome Measure (WhOM) were selected and pilot tested using QUEST 2.0. These studies represent an important step in the development and definition of a PMD assessment and training program to be implemented in routine clinical activities in a regional center for assistive technology in Italy. The measures, the circuit and the program will be further tested in future for validity and reliability in order to assess their efficacy in helping professionals to select the most adequate PMD for users, to conduct specific PMD training, and to evaluate PMD outcomes.
Neutrophils and Granulocytic MDSC: The Janus God of Cancer Immunotherapy
Authors: Zilio Serena , Serafini Paolo
Published: September 2016

Neutrophils are the most abundant circulating blood cell type in humans, and are the first white blood cells recruited at the inflammation site where they orchestrate the initial immune response. Although their presence at the tumor site was recognized in the 1970s, until recently these cells have been neglected and considered to play just a neutral role in tumor progression. Indeed, in recent years neutrophils have been recognized to play a dual role in tumor development by either assisting the growth, angiogenesis, invasion, and metastasis or by exerting tumoricidal action directly via the secretion of antitumoral compounds, or indirectly via the orchestration of antitumor immunity. Understanding the biology of these cells and influencing their polarization in the tumor micro- and macro-environment may be the key for the development of new therapeutic strategies, which may finally hold the promise of an effective immunotherapy for cancer.
Au fondement des politiques d’immigration et de l’asile en Europe
Authors: Duvivier Émilie
Published: September 2016

Les discours sécuritaires sur les migrants, les tentatives toujours croissantes d’identification et de contrôle, s’inscrivent dans un long passé historique dont les traces demeurent visibles dès le XIX e  siècle. Alors que les États européens se sont progressivement attachés à protéger leurs frontières, garantissant des droits particuliers aux membres de leur communauté, sont peu à peu apparues des lignes de clivage entre nationaux et étrangers. Interroger l’évolution de la gestion politique de l’immigration et de l’asile en Europe amène à réfléchir au processus de construction des frontières entre les in et les out , entre ceux qui font partie de la communauté et ceux qui en sont exclus ; et donc par voie de conséquence, au processus de nationalisation des sociétés européennes. Cet article s’intéressera donc à l’histoire européenne du tracé des frontières en interrogeant l’évolution du droit et des pratiques des gouvernements en matière d’immigration et d’asile. L’analyse sociologique et historique proposée s’attachera à réfléchir aux modalités d’encadrement et de gestion des migrations par les États, en replaçant cette question dans le temps long, pour observer l’évolution des tensions à l’œuvre, ses invariants et ses métamorphoses.
L’immigration en France : variations politiques et invariants représentationnels
Authors: Mathieu Sophie
Published: September 2016

Le contexte migratoire en France aujourd’hui est relaté dans les médias et les discours politiques sous un angle peu objectif. On entend souvent parler d’une « crise des migrants » et du danger pour l’économie, les valeurs françaises et à plus forte raison la sécurité, que représenteraient les réfugiés syriens arrivant « en masse » vers l’Europe. Cette situation semble former un problème moderne sans précédent. Pourtant, elle est, dans une certaine mesure, l’actualisation de formes représentationnelles anciennes et jalonnant l’histoire de la France. Quelles sont les évolutions dans le rapport que la France entretient avec ses étrangers ? Et quelles sont au contraire les continuités logiques et intégrées qui déterminent en partie les politiques en matière d’immigration aujourd’hui ?
Orthopedic Surgeons' Management of Elective Surgery for Patients Who Use Nicotine
Authors: Lilley Matthew , Krosin Michael , Lynch Tennyson L. , Leasure Jeremi
Published: September 2016

Despite significant research documenting the detrimental effects of tobacco, the orthopedic literature lacks evidence regarding how surgeons alter their management of elective surgery when patients use nicotine. To better understand how patients' use of nicotine influences orthopedic surgeons' pre- and postoperative management of elective surgery, a 9-question paper survey was distributed at the 2012 annual meeting of the American Academy of Orthopaedic Surgeons among attending US orthopedic surgeons, including general orthopedists and specialty-trained orthopedic surgeons. Survey questions focused on attitudes and practice management regarding patients who use nicotine. Using a chi-square test, no statistically significant variation was observed between subspecialists and general orthopedists or among different subspecialties. Ninety-eight percent of the orthopedic surgeons surveyed counseled tobacco users about the adverse effects of nicotine. However, approximately half of all of the respondents spent less than 5 minutes on perioperative nicotine counseling. Forty-one percent of all of the respondents never delayed elective surgery because of a patient's nicotine use, followed closely by 39% delaying surgery for less than 3 months. Subspecialty had little influence on how orthopedic surgeons managed nicotine users. The high rate of counseling on the adverse effects of nicotine suggested agreement regarding the detrimental effects of smoking. However, the study population infrequently delayed surgery or used smoking cessation measures. Studies are needed to determine why few surgeons frequently alter the management of nicotine users and what modifications in orthopedic practice could improve outcomes for these patients. [
Orthopedics.
2017; 40(1):e90–e94.]
Vitamin D receptor gene polymorphisms in Sudanese children with type 1 diabetes
Authors: Khalid Khalid Eltahir
Published: September 2016

Type 1 diabetes mellitus (T1DM) is a T cell mediated autoimmune disease. Vitamin D was found to suppress the incidence of diabetes when bind to its receptor (VDR), probably by suppressing T cell activations. Thus the VDR gene polymorphism may have an impact on pathophysiology of this disease. Since there was no consistent association between VDR polymorphisms and the risk of T1DM, this study aimed to investigate a VDR gene polymorphism in Sudanese children with T1DM. We examined the VDR gene Bsm1 (rs1544410), Apa1 (rs7975232), and Taq1 (rs731236) single nucleotide polymorphisms in 174 children with T1DM, and 56 children as control, and the association of these polymorphisms with the diabetic control. Among study patients, the majority (85.63%) of diabetic patients reported metabolically poor controlled (HbA1c > 8%). As compared with the control, patients with T1DM presented more commonly with Bsm1 B allele (p = 0.001; OR 0.283; 95% CI 0.131–0.609) and Taq1 T allele (p = 0.05; OR 2.429; 95% CI 1.073–5.496). Apa1 A allele was less common in patients with T1DM without statistical difference (p = 0.862; OR 1.085; 95% CI 0.546–2.156). Our study suggests that, Bsm1 and Taq1 polymorphisms of the VDR gene associated with the prevalence of T1DM.
Optimization and Performance Analysis of Uncoated and Coated Carbide Inserts during Hard Turning AISI D2 Steel Using Hybrid GRA-PCA Technique
Authors: Senthilkumar N. , Selvakumar V. , Tamizharasan T.
Published: September 2016

In this analysis turning parameter optimization is performed during machining AISI D2 steel with uncoated and coated cemented carbide cutting inserts using a hybrid multi-objective optimization technique Grey relational analysis (GRA) and Principal Component analysis (PCA). A L16 Taguchi’s orthogonal array design is selected for basic experimental design considering four levels for the chosen four parameters. Output performance measures viz., tool wear, roughness on finished surface and material removed are evaluated by determining grey relational coefficient, and deriving multi response performance index (MRPI) using principal components. Contribution of coated cutting insert is 72.87% towards the MRPI and 17.15% contribution by feed rate, as determined from Analysis of Variance (ANOVA). Confirmation experiment performed with optimum conditions provides lower tool wear, higher material removal and good surface finish. The MRPI of the confirmation experiment is also confirmed by calculating the confidence interval.
Determination of Material Removal Rate and Radial Overcut in Electro Discharge Machining of AISI 304 Using Dimensional Analysis
Authors: Bhaumik Munmun , Maity Kali Pada , Mohapatra Kasinath Das
Published: September 2016

Electro discharge machining (EDM) is a most commonly used machining process among all the non-conventional machining process which removes materials via electrical and thermal energy. The primary goal of EDM is to get more material removal rate (MRR) with lower radial overcut (ROC). Normally, the responses are predicted using empirical models which are limited to only machining parameters and they do not consider the effects of work material properties on the process performance. Therefore in this study, a model has been developed including machining parameter as well as thermo-physical property of work material. In this investigation, a semi-empirical model has been established for the material removal rate (MRR) and radial overcut (ROC) by adopting the dimensional analysis technique. Dimensional analysis is a technique of dimensions and a mathematical technique that deals with the physical quantities concerned with the experiments to formulate a model for the response in terms of response control parameters as well as some physical properties of the materials. Buckingham’s л theorem is a main theorem in dimensional analysis and it is a signification of Rayleigh’s method of dimensional analysis. The theory is applied to gather each and every variable presenting the problem in a number of the dimensionless products. For this study, the thermo-physical properties viz. density, thermal conductivity and coefficient of thermal expansion and machining parameters like peak current, pulse on time, gap voltage and duty cycle are considered as input factor. AISI 304 stainless steel used as work material and Tungsten carbide is used as tool material for this investigation.
Experimental Investigation and Process Optimization on Shot Peening of Aluminium Alloy (AA6061)
Authors: Balaji D.S. , Jeyapoovan Thangasamy , Guhan C.
Published: September 2016

Shot peening operation is used to improve the mechanical properties of the materials. In this study new rotary peening machine is fabricated. The Hardness and Compressive stress were investigated with help of Vickers Hardness and UTM respectively. The peening parameters such as number of balls (75,100,125), diameter of ball (8,10,12mm), speed (200,300,400rpm) is considered and experimental setup is formulated by L9 orthogonal array. The above parameters are optimized by Taguchi method and MINITAB software. The microstructures of the sample are viewed with help of SEM images.
Optimization of Weld Parameters and Weld Bead Dimensions in Welding of 0.3%C-Cr-Mo-V Steel by Gas Tungsten Arc Welding Process
Authors: Radhakrishnan K. , Muralidharan V.
Published: September 2016

ISRO space programs use Maraging Steel for its Solid rocket motor casings. Because of its higher cost and limitations in the availability,there is a need to develop alternate to this steel.ISRO has developed a unique material as a alternative to Maraging Steel namely 0.3%C-Cr-Mo-V steel (Electro Slag Refined modified 15CDV6 steel-ESR MOD 15CDV6). This material is being considered for making rocket motor casings and considered as substitute as well as replacement for Maraging Steel.Weldability is an important factor considered for fabrication of this material in the areas of rocketry.Since it is a new material, enough studies and welding details are not available to exploit this material for aero space applications.Among the various welding methods available in the welding of steels,GTAW (Gas Tunsten Arc Welding) process selected for undertaking this study because this process is clean,contamination free, easily adaptable and generally suitable for welding of high strength alloy steel.Literature survey indicates not much work has been reported in welding of such low alloy high strength steel with conventional welding methods.Similarly effect of heat treatment on weldments,quench characteristics,hardness response etc.also not available much. Hence, these factors are main reason to undertake this study.This paper is limited to studying , fixing of weld parameters and weld bead dimensions. In this expriment the welding parameters , its response for each set of experiments and influence on weld dimensions are studied.In this work a combination of weld parameters were selected using Design of Experiment (DOE) principle with three levels and four parameter (variables).Totally nine experiments with different combination of parameters conducted on the test coupons of size 8×200×150mm.The chemistry of parent metal and filler rod remains same. Three levels of current and voltage,and correspondingly other parameters like root gap,number of passes and welding speeds were employed.Details like the amount of shielding, purging gas used and quantity of flow are noted.Weld bead dimensions like bead width –B,reinforcement-R,penetration –r,penetration height-b are chosen as response.All the nine test coupons were subjected to Liquid Penetrant Test (LPT), X-ray radiography and found defect free.
Effect of Graphene Platelets/Fiber on Plastics Nanocomposites under Low-Velocity Impact Response
Authors: Subha S. , Krishna Battu Sai , Singh Dalbir , Gokulnath R.
Published: September 2016

In this study, an attempt has made to explore the low-velocity impact response of a Carbon/epoxy laminate (CFRP) and E-Glass/epoxy laminates (GFRP). The composite was reinforced with Graphene Nanoplatelets (GnPs) and impact energy absorption capacity was studied. The plain GFRP and plain CFRP were served as a baseline for comparison. These composite laminate plates were fabricated using hand layup technique. The tests were carried out on the laminate plate as per ASTM D5628 FD. Impact tests were performed using a specially designed vertical drop-weight testing machine with an impactor mass of 1.926 kg. The result shows that laminate plate reinforced with GnPs reinforcement enhances the impact energy absorption capacity of the composites almost 4.5 % in the case Carbon/epoxy laminate and 3.5 % in the case of and E-glass/epoxy laminate. The enhanced impact resistance could be attributed to increased interlaminar fracture toughness of the fibres.
Comparison of PSO, AGA, SA and Memetic Algorithms for Surface Grinding Optimization
Authors: Babu K.
Published: September 2016

In striving to remain competitive in the global market, the concept of optimization of manufacturing processes has been extensively employed to meet the diverse production requirements. Optimization analysis of machining processes is usually based on either minimizing or maximizing certain objective functions. Recently, various non-traditional optimization techniques have evolved to optimize the process parameters of machining processes. The objective of this work is to study the effectiveness of the most commonly used non-traditional optimization methods as applied to a particular machining optimization problem. In this work, surface grinding processes are optimized using i) Particle Swarm Optimization (PSO) ii) Adaptive Genetic Algorithm (AGA) iii) Simulated Annealing (SA) and iv) Memetic algorithm (MA). Memetic algorithm used here has two variations as MA-1 and MA-2, each having the combination of PSO and SA and AGA and SA respectively. The mathematical model of surface grinding operations was adopted from a literature. A computer program was written in Visual C++ for the optimization computations. The computation results of various optimization methods are compared and it is observed that the results of PSO method have outperformed the results of other methods in terms of the combined objective function (COF).
Parametric Influence of Friction Stir Welding on Cast Al6061/20%SiC/2%MoS2 MMC Mechanical Properties
Authors: Bhojan A. , Senthilkumar N. , Deepanraj B.
Published: September 2016

In this work, effect of tool speed and direction of tool rotation of friction stir welding (FSW) process on the cast MMC is analyzed. Aluminum 6061 alloy reinforced with 20% silicon carbide particles added with 2% molybdenum disulphate is prepared by die casting process. Macro and micro-structural analysis is performed to study the size and shape of the constituents, to discover the defects associated with stir welding and quality of weld. Micro-hardness observations are carried out on the parent metal, FSW zone and heat affected zone. It is observed that FSW with high speeds develops higher hardness and most of the higher hardness value occurs in in the order of FSW welding zone, center zone and heat affected zone, and also hardness value of clockwise tool rotation is greater than anti-clockwise tool rotation.
The Study of the Mechanical Properties of Aramid Fiber Reinforced Epoxy Resin Composite
Authors: Akhil K.T. , Blaise Solomon , Davis George , Shunmugesh K. , Genuvin Cyriac , Bins Paul
Published: September 2016

This paper studies the mechanical properties of the aramid fiber reinforced epoxy resin composite by varying the percentage composition. Three different compositions of aramid fiber are 30 %, 35 % and 45 % by weight. The aramid epoxy composite was manufactured by the vacuum suction method. The manufactured composites are then cured by the hot air oven for 180 minutes. The prepared composites undergo through various tests such as the tensile test, hardness test and impact test. The results of the tests on the three compositions analyzed and variation in its mechanical properties is noted.
Dissimilar Study on Friction Welding of AA 2025 Tube Plate to Copper Tube Using an External Tool
Authors: Gokul G. , Senthil Kumaran S.
Published: September 2016

In this project the feasibility of friction welding in tube to tube plate using an external tool (FWTPET) of commercial Copper and Aluminum 2025 tube plate is investigated using an clearance fit method and the process parameters have been prioritized using Taguchi’s L27 orthogonal array. Than experiment is conducted and take results are compressive strength and hardness testing, Radiography test, Scanning Electron Microscopy and Energy Dispersive Spectroscopy testing. Aluminum 2025 are widely used in aerospace, automotive, marine, defense, construction etc. Friction welding is preferred for joining these materials as it is a solid state forge welding process and problems related with welding of aluminum tube plate and copper tube can be subdued through this process. This welding process is a solid state welding procedure that uses a non-consumable rotating tool that is permitted to rub against the work piece hence generating frictional heat. When the weld constraints such as tool rotation speed, welding time, axial load are optimum the friction between the work piece and the tool generates enough heat to create a plastic deformation layer at the weld interface. The process doesn’t involve any melting process and whole process occurs in solid state through plastic deformation and mass flow among the work pieces. The experimental investigation of FWTPET is done by varying the friction welding parameters such as work piece rotation speed, depth and projection. The work piece is rotated at the speeds 285 rpm, 480 rpm and 750rpm, projection 0 mm,1 mm,2 mm and depth are0.5 mm,1 mm,1.5 mm.The experiment is done in a general purpose vertical milling machine. To hold the work piece a fixture is designed. A tool is also designed. This work confirms that a high quality tube to tube plate joint can be achieved using FWTPET process.
Application of Artificial Neural Network (ANN) for Predicting the Wear Behaviour of Al 2219-SiCp Composite
Authors: Radhakrishnan Ganesh , Kesavan Chandrasekaran , Ramesh Vignesh , Anandan Tamilarasan
Published: September 2016

In the present study, artificial neural network (ANN) model was developed to predict the wear characteristics of Al 2219-SiCp composite. In the development of predictive model, weight fraction of the reinforcement, sintering temperature, applied normal load on the pin and disc speed were considered as model variables. Full factorial experiments were carried out and observed wear characteristics were taken as input for the model. A feed forward back propagation hierarchical neural network was considered in the study. Out of 81 datasets, 49 sets of data were used for training, 16 sets of data for validation and 16 sets of data for testing. The results exhibit good prediction accuracy of about 85% on average of all wear characteristics and percentage error was within the acceptable limits.
Investigation of Mechanical and Tribological Behaviour of Dual Particles Reinforced Al Matrix Composites
Authors: Mohanavel V. , Rajan K. , Karthikeyan S. , Naveen Kumar M. , Yoganandam K.
Published: September 2016

In the present scenario, dual particles reinforced aluminum matrix composites have a vast number of applications in aerospace, marine, transportation, structural and non-structural applications like drive shaft, connecting rod, piston and brake drum. The main objective of this work is for evaluating the mechanical and the tribological behavior of aluminium oxide and graphite particulate reinforced with AA6351 composites were prepared by liquid metallurgy route (Stir casting). Hardness and tensile strength of the composite and the base alloy were investigated. The microstructure of manufactured composite and the base alloy were examined by an optical microscope. Optical microscopy analysis confirmed the nearly uniform distribution of Al2O3/Gr twin particles in Al matrix. The tensile strength and hardness of the composites have significantly improved by the presence of Al2O3/Gr.
Effective Stiffness Behaviour of Sandwich Beams under Uncoupled Bending and Torsion Loadings
Authors: Silva Hugo Miguel , Meireles José Filipe
Published: September 2016

Sandwich geometries, mainly in the form of panels and beams, are commonly applied in various transportation industries, such as aerospace, aeronautic and automotive. Sandwich geometries represent important advantages in structural applications, namely high specific stiffness, low weight, and possibility of design optimization prior to manufacturing. The aim of this paper is to uncover the influence of the number of reinforcements (ribs), and of the thickness on the mechanical behavior of all-metal sandwich panels subjected to uncoupled bending and torsion loadings. In this study, four geometries are compared. The orientation of the reinforcements and the effect of transversal ribs are also considered in this study. It is shown that the all the relations are non-linear, despite the elastic nature of the analysis in the Finite Element software ANSYS MECHANICAL APDL.
Conceptual Design of Innovative Eco-Friendly Windmill
Authors: Stephan Thangaiah I.S. , Sevvel P.
Published: September 2016

A wind turbine performs the function of converting the energy (kinetic) derived from the wind into another form of energy (mechanical) which is employed for the purpose of driving the generator which in turn generates electricity from this mechanical energy. The most common types of windmills employed in practice include horizontal and vertical axis wind mill. These windmills are fabricated in different structures for producing electricity. The main objective of this paper is to design an innovative eco friendly windmill to overcome the various difficulties existing in conventional windmills. In conventional windmills, the propeller rotation depends on the velocity of wind flow in the environment. But in this paper, we have fabricated an innovative eco friendly windmill in which, the propeller rotation is increased four times for the wind velocity in the surroundings.
Dynamic Analysis of Faulty Rotors through Signal Processing
Authors: Bhargav Sai Cherukuri , Mallikarjuna Reddy D.
Published: September 2016

In this study, an effective method based on wavelet transform, for identification of damage on rotating shafts is proposed. The nodal displacement data of damaged rotor is processed to obtain wavelet coefficients to detect, localise and quantify damage severity. Because the wavelet coefficients are calculated with various scaled indices, local disturbances in the mode shape data can be found out in the finer scales that are positioned at local disturbances. In the present work the displacement data are extracted from the MATLAB model at a particular speed. Damage is represented as reduction in diameter of the shaft. The difference vectors between damaged and undamaged shafts are used as input vectors for wavelet analysis. The measure of damage severity is estimated using a parameter formulated from the distribution of wavelet coefficients with respect to the scales. Diagnosis results for different damage cases such as single and multiple damages are presented.
Feasibility of Using Wind Mill for Saw Milling
Authors: Rabbani A.Md. , Natarajan Ramakrishnan
Published: September 2016

Everything that happens in the world is an expression of energy in one of its forms. “Energy can neither be created nor be destroyed. It can only be converted from one form into another”. So wind energy is converted from one form to another. Wind energy is readily converted into mechanical energy through the turbine blades. This mechanical energy can be used for saw milling applications. In this paper we concentrate on Design of Shaft, Bevel gear and Torque Transmission system.
Design of Solar Thermal Combined Power and Cooling System Using LiBr-Water as Working Fluid
Authors: Shankar R. , Srinivas T.
Published: September 2016

The integration of power and vapor absorption refrigeration cycle overcomes the disadvantages of power used for the compression refrigeration and also produces additional power for other purposes (Low pressure turbine). The integration is done by making the heat exchanger and generator as common and separate super heater and reheater is used to run the high pressure turbine (HPT) and low pressure turbine (LPT). The maximum total power output of 69.78 kW and 31.86 kW is obtained for HPT and LPT at the atmosphere temperature 30 °C and separator temperature 180 °C. At the same collector exit and atmosphere temperature shows the maximum cooling output of 188.88 kW. The additional advantages of integrating the power and cooling cycle’s shows the choice of choosing the need of only power only cooling and both power and cooling. The analyses are done for various separator temperature and strong solution concentration.
Numerical Modeling of Energy Absorption Behaviour of Aluminium Foam Cored Sandwich Panels with Different Fibre Reinforced Polymer (FRP) Composite Facesheet Skins
Authors: Nalla Mohamed M. , Ananthapadmanaban D. , Selvaraj M.
Published: September 2016

Sandwich structures based on Fibre Reinforced Polymer (FRP) facesheet skins bonded with low density aluminium foam core are increasing in use in aerospace and marine industries. These structures are very sensitive to high velocity impact during the service. Therefore, it is necessary to study the energy absorption of the structures to ensure the reliability and safety in use. Experimental investigation of these transient events is expensive and time-consuming, and nowadays the use of numerical approaches is on the increase. Hence, the purpose of this paper is to develop a numerical model of sandwich panels with aluminium foam as a core and Glass, Carbon and Kevlar Fibre Reinforced polymer composite as faceplate, subjected to high velocity impact using ABAQUS/Explicit. The influence of individual elements of the sandwich panel on the energy absorption of the structures subjected to high velocity impact loading was analysed. Selection of suitable constitutive models and erosion criterion for the damage were discussed. The numerical models were validated with experimental data obtained from the scientific literature. Good agreement was obtained between the simulations and the experimental results. The contribution of the face sheet, foam core on the impact behaviour was evaluated by the analysis of the residual velocity, ballistic limit, and damaged area.
Impact of Oxygenated Additives on Performance Characteristics of Methyl Ester in IC Engine
Authors: Yuvarajan D. , Pradeep K. , Magesh Kumar S.
Published: September 2016

In this present work, the impact of blending n-butyl alcohol, a next generation biofuel with jatropha biodiesel on the performance of a diesel engine are examined. Tests were performed on a constant speed compression ignition engine using n-butyl alcohol / jatropha biodiesel blends. N-butyl alcohol was added to jatropha biodiesel by 10, 20 and 30% by volume. Performance parameters namely break thermal efficiency (BTE), Brake specific fuel consumption (BSFC) and Exhaust gas temperature (EGT) were analyzed in this work. It was experimentally found that by adding n-butyl alcohol to neat jatropha biodiesel, significant reduction in viscosity was observed. In addition, break thermal efficiency was increased by 0.8 % due to improved atomization of the blends. Further, brake specific fuel and exhaust gas temperature was further reduced due to lower viscosity and improved combustion rate with addition of n-butyl alcohol to jatropha biodiesel.
Failure Evaluation and Analysis of Mechatronics-Based Production Systems during Design Stage Using Structural Modeling
Authors: Loganathan M.K. , Goswami Priyom , Bhagawati Bedabrat
Published: September 2016

A method based on structural modelling is developed for failure evaluation and analysis of mechatronics-based production systems. Majority of the elements in production systems are mechatronics-based, which includes various elements such as; electrical, electronic and mechanical. Each of these may have different failure types that may be interdependence/interactive. The reliability of the system mainly depends on how well the failures are taken care of during design stage. In general, individual failures are generalized into probable failure modes and early identification of these helps to reduce their probability. However, consideration of failures and their interdependence / interactions will help to evaluate and analyse the failures of complicated systems in an efficient and effective manner and increase the inherent system reliability. The system structure modeling helps in this regard. Digraph model, in conjunction with matrix method, is employed for failure evaluation and analysis of a mechatronics-based production system based on its structure.
Design of Leg Wheel Hybrid Hexapod with C-Leg Analysis
Authors: Vasanth S. , Harikrishnan M. , Abbhivignesh K. , Karthikeyan B. , Vignesh M.
Published: September 2016

The conventional mobile robotic platforms which either uses wheels or legs are quite familiar and each one of them has its own advantages and disadvantages. The wheeled robot is suitable for only plain and smooth terrain, whereas the legged robot can travel in any kind of terrain but is comparatively slower than the wheeled robot. So, a hybrid of both wheeled and legged platform would be quite suitable for any kind of terrain. The primary focus of this paper is to design and develop a leg-wheel hybrid robotic platform with a concurrent engineering and mechatronics approach to produce results with optimised design metrics at each and every stage of its development. An overall view of the entire mechatronics system is considered for design and development of the robot at each and every stage rather than a sequential engineering approach. This paper details the Finite Element Analysis (FEA) of the C – Legs which are used in the robot.
Advanced Machines and Automation Techniques in Modern Construction Practice and their Possible Use in India
Authors: Mahima S. , Soumya K. , Bahurudeen A. , Haneefa M.K. , Mahalingam B.
Published: September 2016

Robotics and automation are playing very imperative role in the modern construction practice to meet the challenges and expectation specifically in the infrastructural projects. Automation is a tool for operating or controlling different stages of construction process using mechanized and electronic devices or control systems to reduce the human intervention to a minimum. The design and implementation of these automation technologies has shown progressive outcomes compared to conventional methods. Moreover, considerable improvement in working condition, reduction in accidents and significant increase in production have been evidently observed in the recent construction projects as well as in the earlier research studies. Although several countries have adopted automation in their construction projects, application of these techniques in India is limited to a greater extent due to lack of proper guidelines and specifications. It is important to develop appropriate standards and guidelines for Indian construction sector. This paper reviews different automation techniques that are currently used in many parts of the world and suggestions for their application in the Indian construction scenario are discussed in detail. Moreover, guidelines for efficient design and implementation of automation techniques in India are highlighted in this paper.
Evaluation of Th9 lymphocytes in peripheral blood of rheumatoid arthritis patients and correlation with anti-tumor necrosis factor therapy: results from an in vitro pivotal study
Authors: Talotta R. , Berzi A. , Atzeni F. , Dell'Acqua D. , Sarzi Puttini P. , Trabattoni D.
Published: September 2016

The aim of this study was to determine the prevalence of T helper 9 (Th9) lymphocytes in rheumatoid arthritis (RA) patients and to identify a possible association between the percentage of Th9 and the discontinuation of a biological treatment with an anti-tumor necrosis factor (TNF) (infliximab). We collected peripheral blood mononuclear cells (PBMCs) from 55 consecutive RA outpatients and 10 healthy controls. Among RA patients, 15 were not receiving any immunosuppressive drug, 20 were successfully treated with infliximab and 20 discontinued infliximab because of adverse events or inefficacy and were treated with other biological agents. PBMCs were cultured with/without infliximab 50 mg/L for 18 h, and the percentage of Th9 cells was assessed by means of flow cytometry. Th9 lymphocytes were identified as interferon gamma, interleukin (IL)4-, IL17-, IL9-secreting cluster of differentiation 4 (CD4)+ T cells. Cytometric analysis revealed no significant decrease in the percentage of Th9 cells after infliximab exposure in any of the groups, although it was lower in healthy controls than RA patients either before and after the infliximab stimulation assay. Th9 cells are IL-9-secreting T helper lymphocytes whose role in RA is still poorly known. IL-9 levels are increased in RA patients, in whom this cytokine plays a crucial role. Th9 cells are the major producers of IL-9, and their prevalence is higher in RA patients than in healthy subjects; however our experiment in vitro does not demonstrate an association between Th9 lymphocytes and the response to infliximab. Further studies are required to evaluate the real involvement of Th9 population in the immunogenicity of anti-TNF agents.
Efficacy of high-dose methylprednisolone pulses in a child with noninfectious persistent pleuropericarditis revealing systemic juvenile idiopathic arthritis
Authors: De Rosa G. , De Nisco A. , Piastra M. , Valentini P. , Rigante D.
Published: September 2016

Not available
Severe psoriatic dactylitis: when psoriasis involves beyond the skin
Authors: Husein-ElAhmed H.
Published: September 2016

Not available