On-line optimisation and experimental design analysis for the investigations on the surface roughness produced by roller burnishing: a thesis submitted in partial fulfilment of the requirements for the degree of Master of Technology in Manufacturing and Industrial Technology at Massey University

This thesis describes the improvement of the Surface finish of metals by a cold working, non-metal removal and plastic deformation process called roller burnishing. Roller burnishing is a popular finishing process. Surface finish has a positive and prolonged effect on the functioning of the machined parts. In this work roller burnishing is used to get a high quality surface finish on different materials like aluminum, copper, mild steel and brass. A roller burnishing tool was designed and fabricated for the project. A test rig was set up on a center lathe to conduct experiments. The angle of approach and radius of the roller burnishing tool were checked for optimisation. Number of passes of the tool was also one of the factors under study for the optimisation. The surface finish of the roller burnished cylindrical surfaces was examined for the soft materials like Aluminum and Copper and also for the hard materials like Mild Steel and Copper. The optimum values of feed, speed and depth of penetration were suggested by conducting a number of experiments varying one factor-at-a-time holding the rest constant. Since all the factors are interdependent, varying one-factor-at-a-time and keeping the rest constant method of experimental optimisation technique will not give accurate results either for the main effects or any interactions present. At same time it is not possible to vary more than one factor at a time experimentally. Hence a theoretical approach focused on the computer based, process parameters and surface quality data acquisition from the shop floor was suggested. The collected data was then analysed by Design of Experiments method, an advanced statistical quality analysis method, to determine the significant process parameters influencing the surface finish. The basic design and analysis of the process was carried out by full factorial and ANOVA for the two level three factor ( 2 3 ) experimental design. More experiments for roller burnishing process were conducted for collection of data using experiments designed by the Central Composite Design (CCD) method. These experiments were used to determine the interactions among the factors. The analysis was carried out by the Response Surface Methodology (RSM) to find the optimum values of the more significant process parameters. The final surface finish for mildsteel was found to be 0.32µm with a feed of 85µm/rev and depth of penetration of 70µm. The results of both experimental and theory were compared

Compartive Study OF Experimental and Simulated Results of Compression Test on Epoxy Based E-Glass/Carbon Fiber Reinforced Polymer Composite Laminates

In this study, compressive strength and contraction of Polymer Composite Laminates made of E-Glass / Carbon bi-woven fabric reinforced in Epoxy resin matrix has been evaluated experimentally. Composite laminates were fabricated using hand lay-up technique for different ply orientations of 00,300,450,600and stacking sequence of (00/300/450/600) 2S for 2 and 3 mm laminate thickness. The laminates were subjected to vacuum bag moulding (Wet Layup), followed by post curing process at elevated temperatures. The specimen preparation and compression testing were carried out as per ASTM standards using Instron Universal Testing Machine. The Experimental results were validated with FEM analysis by LS-DYNA using LS-PREPOST as the prime post processor and the results of both experimental andFEM show admirable agreement with one another

Formulation and In Vitro Evaluation of Gastroretentive Dosage Form of Gabapentin.

The commonly used and most convenient method of drug delivery is oral route of drug administration . Despite tremendous advancements in drug delivery the oral route remains the preferred route of administration of therapeutic agents because of low cost of therapy and ease of administration leading to high levels of patient compliance. However, this route has several physiological problems, including an unpredictable gastric emptying rate that varies, a brief gastrointestinal transit time, poor bioavailability and the existence of an absorption window in the upper small intestine for several drugs. The main objective of the present study was to develop floating sustained release formulation containing 600 mg of gabapenin for once daily therapy by using polymers like HPMC K100M, Sodium CMC, PEO. Gastroretentive Drug Delivery System improves the bioavailability and therapeutic efficiency of drug. In the preformulation FTIR study was carried out for pure drug (Gabapentin), gabapentin and excipients. It has not shown any interaction . The formulations were prepared by direct compression method . The angle of repose values of all the formulations ranged from 25.61±0.03 to 28.05±0.02. Bulk and tapped densities are used for the measurement of compressibility index.The bulk and tapped density values of all the formulations were ranged from 0.271±0.01 to 0.339�}0.06 and 0.317�}0.06 to 0.366�}0.02 respectively. The carr’s index and hausner’s ratio values for all formulations were ranged from 12.29�}0.05 to 16.35±0.03 and 1.03 ±0.05 to 1.25±0.03 respectively. Thus all formulations exhibited good flow characteristics. The prepared floating sustained release tablets were evaluated for various parameters like thickness, weight variation, hardness, friability and drug content uniformity. The thickness of tablets in all formulations were ranged from 5.2±0.06mm to 5.3±0.05mm. The weight variation of tablets in all formulations were ranged from 948±0.15% to 952.61±0.31%.The hardness of all the formulations F1-F9 was found to be 6.4±0.2(kg/cm2) to 7.4±0.5(kg/cm2). The friability of all the F1-F9 formulations was found to be 0.63% to 0.76% respectively. Drug content of all the formulations were ranged from 99.11±0.14% to 99.61±0.03%. The buoyancy lag time of all the formulations were ranged from 50 Sec to 70 Sec. Compared to all formulations F6 showed the best buoyancy lag time, the buoyancy lag time for F6 was foud to be 50Sec.Total floating time of all formulations was found to be >12 hours. The formulation containing HPMC K 100M shows the higher swelling compared to that of the formulations containing PEO, Sodium CMC. The prepared tablets were then subjected to dissolution test for evaluating the invitro drug release.The dissolution studies were carried out in 0.1N Hcl in USP II appatarus at 37±0.5oC. The results of the dissolution studies indicated that the polymer concentration is having a substantial effect on the drug release from the tablets. Formulation F6 gave better sustained drug release and floating properties in comparision to the other formulations. This formulation took 50Sec to become buoyant. The kinetic study was carried out for F6 formulation which showed that the drug release follows zero order kinetics. The stability studies were carried out for F6 formulation at 40oC ± 2oC / 75% RH ± 5% for 3months. Data revelead that there was no considerable difference. From the above study, it can be concluded that F6 is the optimized formulation which has shown better buoyancy time 50 Sec and drug release 99.85% . However, further in vivo studies can be carried out to support the results

Forceps deliveries and fetomaternal outcome in modern obstetrics

Background: In modern obstetrics practice has witnessed an increase in the caesarean section rates everywhere. The incidence of instrumental deliveries varies between 10-12% in UK. The incidence of instrumental deliveries varies between 2.7-5% in India. There is an urgent need to reintroduce instrumental need in the modern obstetrics. Instrumental delivery is one of the basic functions of emergency care according to WHO. This study was done to know the prevalence, indications and fetal outcomes of forceps deliveries.Methods: A retrospective study was conducted at a tertiary teaching hospital, India from January 2014 to December 2018. All cephalic singleton pregnant mothers who underwent forceps delivery after 28 weeks were included. All the forceps delivery done in twins and breech vaginal delivery were excluded. Demographic data, Indication of forceps delivery, maternal complications of forceps delivery like episiotomy extension, cervical tear, vaginal wall tear, PPH and neonatal outcome like low birth weight, NICU admissions, stillbirth, APGAR score at 1 and 5 minutes were recorded. Equal number of mothers of reproductive age group 20-45 ages who underwent normal non breech vaginal deliveries were randomly selected as control.Results: The prevalence of forceps delivery was 5.25%. The most common indication was fetal distress (55%). Most of the mothers were primigravidas in age group 20-30 years (p2.5 kgs.  APGAR <7 at 1 and 5 min was not significant.Conclusions: As fetal distress is the most common indication, every obstetrician should learn the skill of forceps delivery and it should not be a dying art

Prediction of cutting forces developed during hard turning of hard chrome plated surfaces on EN24 substrate / K. N. Mohandas, C. S. Ramesh and Eshwara Prasad Koorapati

This paper investigates the development of cutting forces during the hard turning of hard chrome plated surfaces on EN24 substrate. The hard turning operation disproves the Merchant's theory of cutting force development during the machining as the hard turning is only a small stock material removal. Various forces produced such as cutting force, feed force and thrust force have been measured during the finish turning. The experimental results have indicated that the feed force is the predominant force out of three different forces developed. This is in good agreement with the available literature. The results obtained from the experimentation were used to predict the optimum cutting conditions in terms of cutting forces. The optimized cutting parameters are feed of 0.08mm/rev, cutting speed of 500rpm and depth of cut of 40jum. The developed mathematical model exhibited satisfactory goodness of the model fit in regression with different PcBN cutting tool inserts. A maximum of 5% variation in the experimental results of the cutting forces when compared with the mathematical model has been observed. This suggests that the developed mathematical model could be employed to predict the cutting forces during hard turning of hard chrome plated surfaces

Classification of Targets Using Statistical Features from Range FFT of mmWave FMCW Radars

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Effect of gamma and electron beam irradiation on the physico-chemical and nutritional properties of mushrooms: a review

The short shelf-life of mushrooms is an obstacle to the distribution and marketing of the fresh product. Thus, prolonging postharvest storage, while preserving their quality, would benefit the mushroom industry as well as consumers. There has been extensive research on finding the most appropriate technology for mushrooms preservation. Gamma, electron-beam and UV irradiation have been shown to be potential tools in extending the postharvest shelf-life of fresh mushrooms. Studies evaluating the effects of ionizing radiation are available mainly in cultivated species such as Agaricus bisporus, Lentinus edodes and Pleurotus ostreatus. This review comprises a comprehensive study of the effects of irradiation on physico-chemical parameters (weight, colour, texture and pH), chemical compounds including nutrients (proteins, sugars and vitamins) and non-nutrients (phenolics, flavonoids and flavour compounds), and on biochemical parameters such as enzymatic activity of mushrooms for different species and from different regions of the world.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support to the research centers CIMO (PEst-OE/AGR/UI0690/2011) and REQUIMTE (PEst-C/EQB/ LA0006/2011). A.S. Fernandes and A.L. Antonio thank FCT, POPHQREN and FSE for their Grants (SFRH/BD/76019/2011 and SFRH/ PROTEC/67398/2010, respectively)