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In this research article, the FSW tool parameters for welding the dissimilar aluminium AA7075-T651 and AA6061 alloy were optimized by implementing the Taguchi method. The FSW parameters related to the tool such as tool offset, pin profile of tool and tilt angle of tool were taken into account for the experimental work. The optimal FSW parameters were confirmed through the confirmation experimental run. ANOVA analysis revealed that the tilt angle of tool is the most dominating factor with contribution percentage of 45.85% and other parameters like tool pin profile involved 40.27% and tool offset involved 12.36% for improving the tensile properties of the FSWed dissimilar AA7075-T651 and AA6061 joint. SEM image of tensile fractured surfaces revealed that most of the specimens were failed due to ductile mode of fracture.

A greenhouse experiment was conducted at College of Agriculture V.C. Farm, Mandya using CRD design with ten treatments and three replications with an objective to study the “Effect of urea modified hydroxyapatite nano fertilizer (UHA) on quality of tomato under greenhouse condition”. Whereas, highest TSS content (5.80 0 Brix) was recorded in the treatment T9 which received 100% Nitrogen-Urea + 1.00% UHA spray and significantly highest lycopene content was recorded in treatment T9 (16.85 mg 100g-1). Highest ascorbic acid content of tomato plant was observed in the treatment T8 (68.04 mg 100g-1) with the application of 100% Nitrogen-Urea + 0.50 per cent UHA spray, which showed significant difference with all the treatments. Increased quality parameters in tomato was attributed to increased growth and yield parameters which is due to slow and sustained release of nitrogen, phosphorus and calcium from urea modified hydroxyapatite nano fertilizer.

A field experiment was conducted during kharif season of 2017 & 2018 and rabi season of 2017-18 and 2018-19 on sandy loam soil of the Agricultural College Farm, Bapatla to evaluate the system productivity of rice- no till ragi cropping system with seven treatments in kharif and in rabi season each kharif treatment divided into four sub treatments. The experiment consisted of seven treatments viz., T1 : 100% RDF (100-60-40 N-P-K kg ha-1) ; T2: 100% RDF + soil application of ZnSO4 @ 50 kg ha-1 ; T3: 125% RDF + soil application of ZnSO4 @ 50 kg ha-1; T4: 75% RDF + poultry manure @ 0.82 t ha-1 + soil application of ZnSO4 @ 50 kg ha-1; T5: 75% RDF + FYM @ 5.0 t ha-1 + soil application of ZnSO4 @ 50 kg ha-1; T6: 50% RDF + poultry manure @1.6 t ha-1 + soil application of ZnSO4 @ 50kg ha-1 and T7: 50% RDF + FYM @ 10 t ha-1 + soil application of ZnSO4 @ 50 kg ha-1. The experiment was laid out in Randomized Block Design and replicated thrice during kharif rice and in rabi four sub treatments i.e, S1:No fertilizer, S2:100% RDF (30-30-20 N-P-K kg ha-1), S3:75% RDF (22.5-22.5-15 N-P-K kg ha-1) and S4:50% RDF (15-15-10 N-P-K kg ha-1) and hence, split plot design was adopted. Maximum rice equivalent yield of ragi (8108, 8570 and 8339 kg ha-1 in both the years and in pooled data respectively) as well as system productivity of rice-ragi (13452, 14036 and 13744 kg ha-1 in both the years and in pooled data respectively) sequence was observed with 50% RDF + FYM @ 10 t ha-1 + ZnSO4 @ 50 kg ha-1 as residual effect, among the fertilizer levels, S2 level i.e., 100 % RDF (30-30-20 kg N-P-K ha-1) on succeeding ragi crop (7413, 8003,7708 and 11893,12641, 12267 kg ha-1 rice equivalent yield and system productivity respectively in both the years and in pooled data).

International audience; Rapidly expanding field of image-guided surgery needs new materials for near-infrared imaging with deep tissue penetration. Here, we introduce near-infrared coating of equipment (NICE) for image-guided surgery based on a series of lipophilic cyanine-7.5 dyes with bulky hydrophobic counterions and a biocompatible polymer, poly(methyl methacrylate). The NICE material exhibits superior brightness (15-20-fold higher) and photostability compared to fluorescent coatings based on commonly used indocyanine green (ICG). It can be deposited on different surfaces and devices, such as steel and gold fiducials, silicone and PVC catheters, polymeric surgical sutures and gauzes. Such coated medical devices show excellent stability in air and buffer for 150 days. Accelerated ageing revealed their shelf-life of 3 years. They are also stable in serum-containing media, whereas ICG-based coating shows rapid dye leakage. NICE is compatible with standard sterilization protocols based on ethylene oxide and vapor. Moreover, our coating material is biocompatible, where cultured cells spread effectively without signs of cytotoxicity. Ex vivo studies suggest that NICE on fiducials can be visualized as deep as 0.5 cm, and NICE on catheters enables their visualization inside ureters and esophagus. Finally, NICE on different medical devices has been validated for image-guided surgery in porcine and human cadaver models. Thus, the developed NIR coating material emerges as a powerful tool for a variety of medical applications.

Fluorescent dyes that emit in the near-infrared (NIR) region gained increasing attention in medical imaging and fluorescence guided surgery. [1,2] Optical imaging allows the surgeons to visualize the normal and diseased tissues in real-time.[2] Particularly interesting in this respect is NIR fluorescent coatings on medical devices such as implants, catheters and stents etc., which are extensively used in various treatments and surgical procedures. However, most of the existing coating materials are composed of either indocyanine green (ICG) or other visible/blue light active fluorophores. ICG-based coatings suffer from limited brightness and poor photostability whereas blue/visible light active coatings are not compatible with well-established laparoscopic systems. [3] Here, we introduce new NIR coating material composed of cyanine dye salts and a biocompatible polymer. [4] The dye is encapsulated into the polymer coating with help of bulky counterions, which, according to our studies on polymeric nanoparticles, [5] prevents dye leakage and minimizes self-quenching. A series of dyes based on cyanine 7.5 family were synthesized and tested. In comparison to ICG-based coatings, our new NIR coatings exhibit superior brightness and photostability Moreover, these coating materials showed good adhesion properties and useful to coat medical devices, including metallic fiducials and catheters. Such coated medical devices show high fluorescence brightness and exceptional stability in air and buffer medium for at least 150 days. Moreover, our coatings are biocompatible and thus, appear promising for biomedical use. We have demonstrated the various possible medical applications of the NIR coated devices (fiducials and catheters) in ex-vivo and in-vivo porcine models. Funding: This work was supported by “NICE” grant of SATT Conectus, Alsace. References: [1] A. H. Ashoka, et. al. J Phys Chem Lett, 2019, 10, 2414. [2] S. Hernot et. al. Lancet Oncol, 2019, 20, e354. [3] Y. Choi et. al. Surg Endosc 2011, 25, 2372. [4] European patent application filed. [5] Reisch, et al., Nature Commun., 2014, 5, 4089.

Manganese tungstate nanoparticles (NPs) were successfully synthesized via a simple and cost effective citric acid assisted solution combustion method. Rietveld refinement of PXRD pattern indicates the formation of pure wolframite phase of manganese tungstate. Transmission electron microscope (TEM) analyses confirm the spherical shaped nanoparticles with average particle size ranging from 12 to 26 nm. The ultra-light combustion derived manganese tungstate NPs exhibits mesoporous nature with the estimated band gap 2.9 eV. The synthesized NPs were found to be an excellent electrode modifier for the simultaneous detection of Pb(II), Cd(II), Cu(II) and Hg(II) ions at nanomolar (nM) concentration. The present electrochemical sensor exhibits wide linearity of 10 – 500 nM with limit of detection based on 3σ method is 3.3, 3.5, 2.9 and 3.1 nM for Pb(II), Cd(II), Cu(II) and Hg(II) respectively. Additionally, room temperature photoluminescence emission spectrum exhibits an intense band at 445 nm that can be attributed to 1A1 ground-state to the high vibration 1T2 energy levels of distorted [WO6] octahedral groups.

Based on a long-term finger millet-groundnut rotation study conducted for 24-years during 1992–2015 under Alfisols at Bangalore, organic and inorganic fertilizer effects on soil organic carbon (SOC...

A new fixed-frequency controlled three-phase dc–dc LCL-type series resonant converter with integrated boost function is proposed for medium to large power applications with wide input voltage variation that is typical of alternate energy sources. The converter includes a dual three-phase LCL-type resonant bridge inverter modules connected in parallel, thus significantly reducing the component stresses when subjected to medium to large power applications. The fixed-frequency control of the output power is achieved by phase shifting the gating signals of one module with respect to the other, while the rectified voltage at the secondary windings of a three-phase high-frequency transformer connected between the two modules is added to the input voltage to boost the supply voltage to the modules. The zero-voltage-switching of all the switches is accomplished by designing the converter to operate in the lagging PF mode for wide variations in the input voltage and the load. Detailed modeling of the three-phase boost section is done and the steady-state analysis of the proposed converter for three-phase LCL-type dc–dc converter modules using complex ac circuit analysis method is presented. For illustration purpose, a dc–dc converter of 600 W is designed, and its performance is verified using PSIM simulations. An experimental model of the converter is built in the laboratory to verify its performance for wide variations in input voltage and load changes.

This work involves the experimental study of drilling EDM parameters for Incoloy 800 alloy. Material erosion rate and tool wear rate has been considered as the response characteristics. Design of experimental runs were framed using CCD based response surface methodology. The experiments are performed in random manner with different combination of pulse current, spark duration, voltage and pulse interval and the results obtained are analyzed using Analysis of Variance (ANOVA). Various 3D plots are generated by using Design Expert software in this work. Discharge current and spark duration were found as the dominant variables for MRR and EWR and the effect is high on these two responses relative to other variables.

Biopolymers have generated mounting interest among researchers and industrialists over the recent past. Rising consciousness on the use of eco-friendly materials as green alternatives for fossil-based biopolymers has shifted the research focus towards biopolymers. Advances in technologies have opened up new windows of opportunities to explore the potential of biopolymers. In this context, this review presents a critique on applications of biopolymers in relation to antioxidant and antimicrobial activities. Some biopolymers are reported to contain inherent antioxidant and antimicrobial properties, whereas, some biopolymers, which do not possess such inherent properties, are used as carriers for other biopolymers or additives having these properties. Modifications are often performed in order to improve the properties of biopolymers to suit them for different applications. This review aims at presenting an overview on recent advances in the use of biopolymers with special reference to their antioxidant and antimicrobial applications in various fields.

The current trends to re-evaluate the need for traditional clay control additives and the interest in increasing hydrocarbon production from secondary fracture networks are leading to the use of more appropriate fluid compositions. Additives historically used to dehydrate or exchange interlayer cations in water-reactive phyllosilicates introduce instability in the reservoir matrix and have been used in shale reservoirs without thorough assessments of potential formation damage. Framing the need for clay control in these reservoirs solely on the need to control water-reactive clays led naturally to the removal of clay control additives from fluids during the recent downturn. While justified from a cost perspective, these simplified fluids were introduced without assessments of the impact of near colloidal (10-40um diameter) fines generation. Completion experts who realize the formation damage risk of fines generation recognized these problems. This paper updates the industry on an approach to proportion clay control and shale stabilization with fluid design better aligned to reservoir mineralogy and the stress introduced on the reservoir during hydraulic fracturing. The paper reports swelling clay control and near colloidal fines evaluations from four world class unconventional oil & gas reservoirs in North America. Reproducible fundamental trends in CST and near-colloidal fines generation data are correlated to clay control additive type and use of oxidative breaker. Additionally, this new test method has the potential to be easily and commercially viable for rapid field evaluation to assess formation damage due to fines generation.

Tetrahedrites are natural earth-abundant minerals consisting of environmentally-friendly elements of copper and sulphur. Recently, research has been focused on the natural and synthetic minerals of tetrahedrite materials for thermoelectric applications. The thermoelectric figure of merit zT of around unity at similar to 723 K for many doped and natural tetrahedrite materials in the past 2-3 years was determined and this value is comparable to conventional p-type TE materials. In this review, a brief history of tetrahedrite materials is followed by information about its crystal structure and chemical bonding, electronic band structure and transport properties. Different synthesis approaches have been summarized. Also, this review outlines the effect of different doping elements on the thermoelectric properties of tetrahedrite materials, and the natural mineral tetrahedrite that can be used as thermoelectric materials.

This study attempted to compare the effect of cow manure vermicompost and inorganic fertilizers on the vegetative growth and fruits of tomato plant (Solanum lycopersicum L.). An air dried sandy loam soil was mixed with five rates of vermicompost equivalent to 0 (control), 5, 10, 15 and 20 t ha-1 and three rates of NPK fertilizer equivalent to 50% (N-P-K = 69-16-35 kg ha-1), 100% (N-P-K = 137-32-70 kg ha-1) and 200% (N-P-K = 274-64-140 kg ha-1). The treatments were replicated three times. The data revealed that shoot length, number of leaves, dry matter weight of shoots and roots, fruit number and fruit weight were influenced significantly (P < 0.05) by the application of vermicompost and NPK fertilizer in the growth media. The highest dose of vermicompost of 20 t ha-1 increased dry weight of shoot of 52 folds and root of 115 folds, number of fruit(s)/plant of 6 folds and mean fruit weight of 29 folds while the highest rate of NPK fertilizer of 200% increased dry weight of shoot of 35 folds and root of 80 folds, number of fruit(s)/plant of 4 folds and mean fruit weight of 18 folds over the control treatment. The growth performance of tomato was better in the vermicompost amended soil pots than the plants grown in the inorganic fertilizer amended soil pots. This study suggested that the vermicompost served as a potential source of nutrients for plant growth.

Millennial generation bank (digital banking) is different from traditional brick and mortar banking service. Digital banking focus on promoting environmental friendly, ethical and transparent banking. This research paper attempts to evaluate the acceptance of new generation banking products among customer its relationship with that Age, Occupation and Educational Qualification. Statistical Tests are applied for analysing and evaluating the objectives. The results of the study implied that majority of the customers are millennial generation and middle age groups are more motivated towards digital banking products. Senior citizens and women are not actively using the service of digital banking and there is also a relationship between digital banking and demographic characteristics. Therefore, the educational qualification has nothing to do with usage of digital banking products, whereas, more awareness is need to be created among the senior age groups individuals.

A high-frequency (HF) isolated dc/ac converter including an unfolding line connected inverter can be used as the interface between a small-scale alternative energy generation system and the utility line. This paper presents the review of operation of several different topologies of HF isolated dc/ac converters. They are designed for illustration purpose and compared for their performance. It is found that the dual-LCL series resonant dc/ac converter can maintain zero-voltage switching (ZVS) operation for all switches with low line-current total harmonics distortion (THD) and high efficiency. Experimental results on a 500-W prototype converter are included for validation purpose.

The material handling is the art of moving, orienting, packing and storing the part. Industrial feeders are used to facilitate the operations by feeding the parts in a specific quantity and at a perfect orientation. It is a tedious task to obtain a particular part orientation, at the assembly station, in a short lead time. To overcome this problem, part feeders are used to segregate and orient parts prior to packing. The natural resting orientation of the part is the orientation in which the part rests on a horizontal hard surface, when dropped from a height. The most probable natural resting orientation of the part has to be identified which helps in the effective design of feeder and orienting devices. In this paper, an attempt was made to study the effect of initial orientation from different heights on natural resting orientation. Drop test was conducted at different heights with each initial orientation. The favorable orientation of the part (or) the most probable natural resting orientation is identified using drop test. In this work, most probable natural resting orientation of a typical asymmetric component, brake pad, is identified.

The objective of the present work is to predict the optimal set of process parameters such as peak current (IP), pulse on/off time (TON/TOFF) and spark gap voltage (SV) to achieve minimum Surface roughness (Ra), wire consumption rate (WCR) and maximum material removal rate (MRR). In this work, experiments were carried out by pulse arc discharges generated between ZnO coated brass wire and specimen (IS2062 steel) suspended in deionized water dielectric. The experiments were designed based on the above mentioned four factors, each having three levels. Custom design based Response Surface Methodology (RSM) is used in this research. 21 runs of experiments were constructed based on custom design procedure and results of the experimentation were analyzed analytically as well as graphically. Moreover the surface roughness after machining was measured by Taylor Hobson Surtronic device. Second order regression model has been developed for predicting Ra, WCR and MRR in terms of interactive and higher order machining parameters through RSM, utilizing relevant experimental data as obtained through experimentation. The research outcome identifies significant parametersand their effect on process performance on IS2062 steel. The results revealed that peak current, pulse on-time and their interactions have significant effects on Ra, whereas pulse off time and peak current have significant effects on MRR and it is also observed that peak current and interaction between peak current and pulse off time have significant effects on WCR. The adequacy of the above proposed models has been tested through the analysis of variance (ANOVA).

In this article, a fixed-frequency phase-shift-controlled full-bridge series-parallel (or LCC-type) resonant converter that uses a capacitive output filter is proposed. Steady-state analysis of this converter is performed by using a complex AC circuit analysis approach. Based on the analysis, a simple design procedure is given and exemplified with a design example of a 200- to 220-V DC input, 300-W, 100-V output converter. The relationship between the design parameters, switch stresses, and converter size is illustrated. Both computer simulation and experimental results on a lab prototype converter are presented to verify the performance of the designed converter for varying input voltage and load conditions. It is shown that this converter requires a narrow variation in pulse width for a wide variation in the load, while the peak current through the switches decreases with the load current. One typical application of this converter is for use as a second stage for AC-to-DC converters.

A pot experiment was carried out to determine the effect of lime and phosphorus on the growth and nutrient uptake by Indian spinach (Basella alba L.) on an acidic soil. The experimental soil was amended with four levels of lime (0, 500, 1000 and 2000 kg CaCO3 ha-1) and phosphorus (P) (0, 50, 100, and150 kgP ha-1) and their combinations. The results showed that lime and P applied separately or in combination had significant (P ·ha-1 lime plus 150 kg P ha-1 had higher uptake of N, K and Ca and better morphological characters that eventually resulted in greater yield compared with other treatments. The results revealed that lime and phosphorus could be used in combination to improve growth performance and nutrient uptake when plants grown in an acidic soil.

A pot experiment was carried out to investigate the yield of Indian spinach (Basella alba L.) and their uptake and availability of phosphorus from lime and phosphorus amended acidic soil. Four rates of lime (L) equivalent to 0, 500, 1000 and 2000 kg CaCO3 ha-1 and four rates of phosphorus (P) equivalent to 0, 50, 100, and 150 kg·P·ha-1 of TSP were applied in combinations as treatments. Dry matter yield, P concentrations in shoot and root and P uptake by Indian spinach were determined after harvesting 10 weeks old plant and soil samples were collected from each pot to measure available P by Olsen method. Both L and P and their combinations had significant (P 0.001) effects on shoot and root biomass, shoot and root P concentrations, P uptake by Indian spinach and P availability. Although lime and P increased biomass production, P concentrations of shoot and root, and its uptake by Indian spinach and available P, this effect was boosted by combining L with P applied. 1000 kg lime plus 100 kg P were adequate for plant growth. Available P was strongly and positively correlated (R2 = 0.909, P = 0.000) with P uptake by plant. Results of the present study indicated that lime and phosphorus could be used in combination to enhance plant growth.

An incubation study was conducted in laboratory to determine the effect of lime (L) as CaCO3 and phosphorus (P) as TSP on soil pH and available soil P in an acid soil. Four rates of L equivalent to 0, 1, 2 and 3 ton CaCO3 ha-1 and four rates of P equivalent to 0, 25, 50 and 75 mg P kg-1 were applied in combinations as treatments. The soil was incubated at field capacity for 8 weeks (wk) after which they were extracted using NaHCO3 (Olsen), Mehlich-3, Kelowna and Bray & Kurtz-1 extractants and soil pH was determined. Lime significantly (P -1 gave the highest available phosphorus. Mehlich-3 method extracted the largest amount of P (14.54 - 67.35 mg·kg-1) while Olsen extracted the smallest amount (3.25 - 32.77 mg·kg-1). The mean extractable P in soils was found to be in the order of Olsen 2 = 0.87 to 0.95).

Spectrally efficient orthogonal frequency division multiplexing (OFDM) offers an ideal solution to inter symbol interference (ISI), by maintaining the orthogonality among subcarriers. For a multi carrier (MC) communication system, the wireless channel impulse response (CIR) varies rapidly under severe channel fading conditions. In addition, estimating the channel characteristics under non-linear time varying random channel environment, is always a tough task for a successful communication of wireless data. In this paper, we present a simple method, based on tunable Q-factor Wavelet transform (TQWT), for OFDM channel estimation. The performance of the proposed TQWT is compared with other well established algorithms. The superiority of the proposed TQWT based channel estimation is evaluated by the bit error rate (BER) and mean square error (MSE) parameters, which shows an improvement.

In general, to mitigate the effect multipath fading in a wireless communication systems, the Rake receiver is used. In this work DTCWT (Dual Tree Complex Wavelet Transform) based rake received is designed for UWB (Ultra-Wide Band) system. UWB transmission is based on pulse position or time modulation as the system transmits data by generating radio energy at specific time interval. DTCWT, templet pulse of the rake receiver are the DTCWT transform components of tree A and tree B of the transmitted pulse. In this paper DTCWT is implemented to single-input-single-output UWB. Its performance is compared with CWT (continuous wavelet transform) rake receiver with variable fingers over UWB channels CM1, CM2, CM3 and CM4.

An electrolyzer is part of a renewable energy system and generates hydrogen from water electrolysis that is used in fuel cells. A dc-to-dc converter is required to couple the electrolyzer to the system dc bus. This paper presents the design of three soft-switched high-frequency transformer isolated dc-to-dc converters for this application based on the given specifications. It is shown that LCL-type series resonant converter (SRC) with capacitive output filter is suitable for this application. Detailed theoretical and simulation results are presented. Due to the wide variation in input voltage and load current, no converter can maintain zero-voltage switching (ZVS) for the complete operating range. Therefore, a two-stage converter (ZVT boost converter followed by LCL SRC with capacitive output filter) is found suitable for this application. Experimental results are presented for the two-stage approach which shows ZVS for the entire line and load range.

A bidirectional LCL-type series resonant converter with capacitive output filter is proposed for the application of capacitor semi-active hybrid energy storage system. The primary side of the converter is controlled using the modified (complementary) gating scheme; while the secondary side of the converter is controlled using the normal gating that is phase shifted with respect to the primary side. The direction of the power flow is determined by the polarity of the phase shift between the primary side and the secondary side of the converter. Steady state analysis of the converter using Fourier series approach is presented. Based on the analysis, a design example with detailed procedures is provided. Next following the design parameters obtained in the design example, a converter is simulated using PSIM simulation software. Finally, experimental results of the designed converter are provided to confirm the theoretical calculations.

Orthogonal frequency division multiplexing (OFDM) system can assure a greater immunity to multipath fading under a wireless communication environment. But the major challenge is to address the issue of high peak to average power ratio (PAPR) in OFDM systems. To reduce the PAPR in OFDM systems, various techniques are proposed by the researchers in the literature. In this paper, a method based on companding transform technique is proposed to accomplish this challenging task. The proposed modified exponential companding transform (MECT) method is attractive for its simplicity and effectiveness for reduction of PAPR in OFDM systems. The performance of the proposed one is evaluated using computational measure, bit error rate (BER). MECT method offers an improved BER and minimized out-of-band interference (OBI) while reducing PAPR effectively when compared to the existing PAPR reduction methods. Simulation results revealed the efficacy of the proposed MECT method in PAPR reduction of OFDM systems.

An 'electrolyser' is part of a renewable energy system (RES), which breaks water down into hydrogen and oxygen gases by passing an electric current through water. A dc-to-dc converter is needed to couple the electrolyser to the system dc bus of the RES. This study proposes a two-stage soft-switched high-frequency transformer isolated dc-to-dc converter for this application. A zero-voltage transition boost converter is used as the front stage followed by an inductor-capacitor-inductor (LCL)-type series resonant converter (SRC) with a capacitive output filter. Since the boost converter maintains almost a constant bus voltage, the LCL SRC can operate with zero-voltage switching (ZVS) for the specified supply and load variations. A systematic design procedure is given followed by a detailed personal simulation program with integrated circuit emphasis (PSPICE) simulation and experimental results for the designed 2.4 kW converter cell to show the performance of the proposed converter configuration.

This paper presents the influence of cylindricity and surface modification on load bearing ability of interference fitted assemblies. Assemblies were made of EN 8 steel with and without (plain) nubs. The influence of cylindrical profile or waviness of pins, with and without nubs on load bearing ability is analyzed by experimental and harmonic analysis. Results show that pins with nubs can carry higher load and pins with and without nubs having harmonics of smaller amplitude can carry higher load for a given interference. Also, increase in average undulation number increases the load bearing ability. Further, finite element method (FEM) was used to evaluate the Von Mises stresses on the performance of interference fitted assemblies. An appropriate finite element model was developed to analyze the pattern of contact stresses in interference fitted assemblies for with and without nubs with varying interference. The results reveal that pins with nubs can with stand higher stresses.

Circuit variability has adverse consequences on design predictability and yield in Nanometer CMOS. Post-fabrication tuning approaches have been targeted in a number of recent works to mitigate this problem. Adaptive Body Bias (ABB) is one of the most successful tuning knobs in use today in high-performance custom design. Through forward body bias (FBB), the threshold voltage of the CMOS devices can be reduced after fabrication to bring the slow dies back within the range of acceptable specs. FBB is usually applied with a very coarse granularity at the price of a significantly increased leakage power. We propose a novel, fine-grained FBB scheme on row-based standard cell layout that enables selective forward body biasing of those rows that contain most timing critical gates, thereby reducing leakage power overhead. This style is fully compatible with state-of-the-art commercial physical design flows and imposes minimal area blow-up. It can be applied without any placement disruption on a fully placed design. Benchmark results show large leakage power savings with a maximum savings of 61% in case of 18% compensation in 45nm and 93% in case of 10% compensation in 32nm with respect to block-level approaches.

This paper presents a phase-modulated high-frequency isolated dc/ac converter as the grid interface in a distributed generation system. The converter includes two full-bridge HF LCL-type resonant inverters working at fixed duty cycle. The power control is realized by means of the phase-shift between the two bridges. Using the LCL-type resonant tank, zero-voltage-switching is achieved for all switches for the whole power range. With the phase-shift modulated sinusoidally, a full-wave rectified output current synchronized with the utility line is obtained, which is unfolded and fed to the single-phase utility line. The analysis is verified with computer simulation results. Experimental data based on a 500-W prototype circuit is included for validation purpose.

A pot experiment was carried out to investigate the comparative effect of city finished compost and NPK fertilizer on the growth and availability of phosphorus to radish (Raphanus sativus L.). An air dried sandy loam soil was mixed with five rates of city finished compost (CFC) equivalent to 0, 5, 10, 20, 40 ton ha–1 and three rates of NPK fertilizer equivalent to 50% (N-P-K = 69-16-35 kg ha–1), 100% (N-P-K = 137-32-70 kg ha–1 K) and 150% (N-P-K = 206-48-105 kg ha–1). Four plants were harvested at 45 days of growth and remaining one plant was harvested at 90 days of growth and separated into leaves and bulbs. After harvest, soil samples were collected from each pot to measure soil pH and available P extracted by Olsen, Mehlich-3, Kelowna and Bray & Kurtz-1 extractants. The growth parameters (length of leaves and bulbs, fresh and dry weight of leaves and bulbs), relative dry matter yield, plant P concentrations, P uptake by radish, soil pH, and available P increased by the rates of CFC and NPK fertilizer treatments. Among the treatments, growth performance of radish was better with the highest rate of 40 t ha–1 CFC treatments. The results obtained from the 5 and 10 t ha–1 CFC treatment were comparable with the results of 50% and 100% NPK fertilizer treatments respectively. Similar effects of amendments were obtained in the case of plant P concentration, uptake of P by plant, soil pH and available soil P concentration. Available P and soil pH showed very strong and positive correlation (P < 0.001) with dry matter yield, P uptake by plant. The P extracted by various extractants also showed strong positive correlation (r = 0.973 to 0.994; P < 0.001 ) each other indicating the suitability of any of the extractants to predict available P. Results of the present study indicated that 10 t ha–1 city finished compost could be used instead of 100% to obtain similar yield and to improve soil conditions.

Integrated production–distribution plan considering three major objectives, viz., total cost minimization, change in labor level reduction, and underutilization minimization, is developed for a renowned bearing manufacturing industry in India. The total cost minimization objective minimizes the regular, overtime, and outsourced production costs along with inventory holding, backorder, hiring/laying-off, and trip-wise distribution costs. The multi-criteria model is solved using a novel simulation-based analytic hierarchy process (AHP)–discrete particle swarm optimization (DPSO) algorithm. The solutions of the AHP-DPSO algorithm are verified using the AHP-binary-coded genetic algorithm solutions. The proposed simulation-based AHP-DPSO solutions are found to be superior. Demand is assumed to vary uniformly, and the simulation-based AHP-DPSO algorithm is used for obtaining the best production–distribution plan that serves as a trade-off between holding inventory and backordering products. In addition to bearing manufacturing industry dataset, two other test datasets are also solved.

This paper presents a three-phase (LC)(L)-type dc-dc series-resonant converter with capacitive output filter. Operation of the converter has been presented using the operating waveforms and equivalent-circuit diagrams during different intervals. An approximate analysis is used, and design procedure is presented with a design example. Intusoft simulation results for the designed converter are given for input voltage and load variations. Experimental results obtained with a 300-W converter are presented. Major advantages of this converter are the leakage and magnetizing inductances of the high-frequency transformer that are used as a part of resonant circuit, and the output-rectifier voltage is clamped to the output voltage. Also, the converter operates in soft switching for the inverter switches with a narrow frequency control range and the tank current decreases with the load current.

Bidirectional dual-bridge dc/dc converter with high frequency isolation is gaining more attentions in renewable energy system due to small size and high-power density. In this paper, a dual-bridge series resonant dc/dc converter is analyzed with two simple modified ac equivalent circuit analysis methods for both voltage source load and resistive load. In both methods, only fundamental components of voltages and currents are considered. All the switches may work in either zero-voltage-switching or zero-current-switching for a wide variation of voltage gain, which is important in renewable energy generation. It is also shown in the second method that the load side circuit could be represented with an equivalent impedance. The polarity of cosine value of this equivalent impedance angle reveals the power flow direction. The analysis is verified with computer simulation results. Experimental data based on a 200 W prototype circuit is included for validation purpose.

This article reports the effect of FSW tool parameters on tensile properties of the friction stir welded AA7075-T651 and AA 6061 butt joint. Aluminium is a widely used material in many engineering applications ranging from packaging material (cans, foil) to transportation (automobiles, aircraft, trucks). Nowadays titanium and composites are growing in use, most of commercial civil aircraft airframes are made from aluminium alloys. Without aluminium, civil and aviation would not be economically viable. In this work, dissimilar aluminium alloys such as AA7075-T651 alloy and AA 6061 alloy of 6mm thickness plate has been friction stir butt welded incorporating FSW tool parameters such as tool tilt, tool offset and pin diameter with central composite design (CCD) by using response surface methodology. It consists of three factors and five levels having 20 experimental runs. From this research, it is found that the joint fabricated with 6mm pin diameter, 0.9 mm tool offset and 3 degree tilt angle exhibited the acceptable tensile strength of 267 N/mm2 compared to other joints. SEM analysis on the tensile fractured surface along with dimples clearly reveals the failure due to ductile behaviour.

The challenge in controlling a three-phase pulsewidth modulation (PWM) rectifier under balanced conditions arises from the fact that the state-space averaged model reported in literature has a multi-input-multi-output nonlinear structure and furthermore exhibits a nonminimum phase feature. In this paper, a simple single-input-single-output model is constructed by separating the d -axis and the q-axis dynamics through appropriate nonlinear feedforward decoupling while maintaining nearly unity power factor operation. With the proposed model, the nonminimum phase feature inherent in an AC-to-DC rectifier becomes a simple right-half-plane zero appearing in the small-signal control-to-output transfer function. In addition, the model exhibits a close similarity to a DC-DC boost converter under both large-signal and small-signal operating conditions. This makes it possible to extend the system analysis and control design techniques of DC-DC converters to the three-phase PWM rectifier also. The validity of the proposed model has been verified experimentally in the frequency domain under open-loop operation of the PWM rectifier. The usefulness of the model is further demonstrated through closed-loop operation of the rectifier with both voltage mode and inner-current-loop-based schemes.

Instantaneous power regulation is an effective way to improve the performance of a pulsewidth-modulation rectifier operating under unbalanced supply-voltage conditions. By properly setting current commands, this approach aims to achieve performance features that are normally achievable only under ideal balanced operating conditions. This paper proposes an instantaneous power-regulation strategy called output-power-control method, in which the current commands are determined so as to appropriately distribute the input power to maintain a constant dc output voltage and sinusoidal line currents. Although the power factor is not directly controlled, it is shown that the proposed scheme results in near unity vector power factor. The current commands are given by a set of simple linear equations in which the proposed control scheme can be easily implemented. Experimental results obtained with a 1-kW laboratory prototype demonstrate that the proposed scheme fulfils all the main objectives of a high-performance rectifier.

This paper introduces average circuit models for switch mode shunt converters coupled with power systems such as active filters and static compensators (STATCOM). These devices absorb or deliver reactive power to the utility network by employing either a fixed or a variable switching frequency (e.g., pulsewidth modulation voltage control or hysteresis current control). Analysis and simulation of these exact devices could be complex under transient and steady state conditions. Ongoing investigations on design of a practical STATCOM show that performing these kind of simulations (e.g., with PSpice) are very sluggish. Here both the fixed and variable switching frequency shunt devices are modeled using an averaging approach, by deriving their state-space equations. An average operator is defined, and applied to the state equation to get averaged mathematical models. Expansion of these models will eventually lead us to average circuit models. Further, the ripple is approximated to provide a correction to the average model. The resulting models produce much faster simulations than their exact devices. Theoretical considerations show that the averaged models agree well with the original system, and this is confirmed by PSPICE and MATLAB simulations. Additionally, experimental results are presented to validate the developed models.

High frequency (HF) transformer isolated DC-DC converter is part of a fuel cell inverter system for utility interface, required to translate the level of low fuel cell stack voltage to meet the peak utility line voltage and provides isolation between inverter and utility line. This paper presents a comparison of various soft-switched HF transformer isolated DC-DC converters for fuel-cell to utility interface application. It is shown that due to wide variation in fuel cell voltage with load variation, none of the voltage-fed converters can maintain ZVS for the complete operating range. Active clamped two-inductor current-fed converter is able to maintain ZVS for wide load and fuel cell stack voltage variations and is suitable for the present application. Analytical, simulation and experimental results are presented to evaluate the performance of the current-fed converter.

A zero voltage switching (ZVS) dc link, single-phase, pulsewidth- modulated voltage source inverter (VSI) is proposed. Operating principle and various operating intervals of the converter are presented and analyzed. Design considerations are discussed and a design example of a 300 VA VSI is given. Experimental results from a laboratory prototype model are presented. ZVS is achieved for forward and reverse power flow, without increasing the voltage stress on the inverter devices.

In this paper, we study the human oculomotor system as a simple mechanical control system. It is a well known physiological fact that all eye movements obey Listing's law, which states that eye orientations form a subset consisting of rotation matrices for which the axes are orthogonal to the normal gaze direction. First, we discuss the geometry of this restricted configuration space (referred to as the Listing space). Then we formulate the system as a simple mechanical control system with a holonomic constraint. We propose a realistic model with musculotendon complexes and address the question of controlling the gaze. As an example, an optimal energy control problem is formulated and numerically solved

A new fixed-frequency controlled 3-phase dc-dc LCL-type series resonant converter with integrated boost function is proposed for medium to large power applications with wide input voltage variation that is typical of alternate energy sources. The converter includes dual three-phase LCL-type resonant bridge inverter modules connected in parallel, thus significantly reducing the component stresses when subjected to medium to large power applications. The fixed-frequency control of the output power is achieved by phase shifting the gating signals of one module with respect to the other while the rectified voltage at the secondary windings of a 3-phase high-frequency transformer connected between the two modules is added to the input voltage to boost the supply voltage to the modules. The zero-voltage-switching of all the switches is accomplished by designing the converter to operate in the lagging pf mode for wide variations in the input voltage and the load. Detailed modeling of the 3-phase boost section is done and the steady-state analysis of the proposed converter for 3-phase LCL-type dc-dc converter modules using complex ac circuit analysis method is presented. For illustration purpose, an example dc-dc converter of 600 W is designed, and its performance is verified using PSIM simulations. An experimental model of the converter is built in the laboratory to verify its performance for wide variations input voltage and load changes.

In order to overcome the software development challenges like delivering a project on time‘, developing quality software products and reducing development cost, software industries commonly uses defect detection software tools to manage quality in software products. Defects are detected and classified based on their severity, this can be automated in order to reduce the development time and cost. Nowadays to extract useful knowledge from large software repositories engineers and researchers are using data mining techniques. In this paper, software defect detection and classification method is proposed and data mining techniques are integrated to identify, classify the defects from large software repository. Based on defects severity proposed method discussed in this paper focuses on three layers: core, abstraction and application layer. The designed method is evaluated using the parameters precision and recall.

Introduction of duty cycle in the binary addressing technique is proposed to enable integration of liquid crystal display drivers with a digital system in a single chip. An analysis of this technique with duty-cycle control is presented. Effects of duty-cycle control on brightness uniformity of pixels in the liquid crystal display are discussed. A system on chip implementation of the technique is also demonstrated.

A high-frequency transformer isolated, fixed-frequency, 3-/spl phi/ single-stage ac-to-dc converter using a boost-integrated bridge converter that employs a new gating scheme is proposed. This converter enjoys natural power factor correction with low line current harmonic distortion and symmetric high frequency voltage and current waveforms while ensuring zero-voltage switching for all the switches for a wide variation in load and line voltage. Various operating modes of the converter are presented and analyzed. Based on the analysis, design curves are obtained and an optimum design is given. A design example is presented. Results obtained from SPICE simulation and a 500 W output experimental prototype are given to verify the performance of the proposed converter for varying load as well as line voltage.

Recent anatomical studies of extraocular muscles (EOM) demonstrate the stability of muscle paths. This is due to the fact that each rectus EOM passes through a pulley consisting of an encircling ring or sleeve of collagen. In this paper, the EOMs are modeled using the Hill type musculotendon complex and the effect of extraocular pulleys are studied. The model proposed by Martin and Schovanec in 1999, for horizontal eye movement has been used as a basic starting point. The extraocular pulleys are then introduced and analyzed mainly to study how Listing's law is enforced and how it implements an oculomotor plant which appears commutative to the brain.

The present study is an attempt to assess the silkworm cocoon production and its profitability in five taluks of Kolar district of Karnataka through structured survey during 2012–13. The sample comprised of 120 families consisting of 440 members with an average of 4.40. The number of adult male and female members constituted 46.14 and 33.41 per cent respectively and the rest were children. The number of illiterates in the sample was to the tune of 33 per cent. Out of total acreage wetland constituted 27.36 per cent while garden land formed 14.53 percent and the land holding pattern indicated the predominance of marginal (47.5 per cent) and small farmers (30 per cent). The holding per family varied from 1.75 to 20.42 acres with an average of 4.13 acre. The total cost incurred for rearing of 8, 000 DFLs per year was worked out to be 713640. Among the total cost, maximum cost was incurred towards the mulberry leaves 455000 (63.75per cent). The minimum cost of expenditure was incurred towards transportation and marketing 5000 (0.70per cent) and other costs were to the tune of 500 (0.07 per cent). The total net earnings from 10 batches per year was estimated to be 19, 13, 000 per 8, 000 DFLs per year with a benefit cost ratio of 1.59. The total investment on building and equipments for rearing of 8000 DFLs per year was worked out to be 30, 290. Among the depreciation cost incurred towards the equipments for rearing of 800 DFLs, the highest was contributed by mountages 25600 during the silkworm cocoon production activities.

The present work is to investigate the effect of significant process parameters on responses and to validate the developed ANN model with the experimental data. To achieve this, 30 number of experiments were carried out on Air Hardened Tool Steel (AISI A2) suspended in deionized water dielectric with copper as tool electrode by using full factorial central composite experimental design based Response Surface Methodology (RSM). The Air hardened tool steel is chosen as the specimen due to its wide range of applications such as in large blanking dies, master hubs, precision tools and coining dies. The various process parameters which can be varied such as Pulse on time, Pulse off time, Peak Current and Voltage are chosen as input parameters. For the selection of dominant process parameters, preliminary experiments were carried out. The output responses viz., Material Removal Rate, Tool Wear Rate, Taper Angle, Circularity and Perpendicularity were measured and analyzed using Design Expert software analytically as well as graphically in order to evaluate the performances of the EDM process. Regression model is developed for predicting Material Removal Rate, Tool Wear Rate, Taper Angle, Circularity and Perpendicularity, in terms of interactive and individual terms of machining parameters through RSM, utilizing relevant experimental results as obtained through experimentation. The research outcome identifies significant parameters and their effects on process performances on AISI A2 tool steel. The adequacy of the above proposed model is also tested using analysis of variance (ANOVA) method. Surface plot for the responses (Material removal rate, Tool wear rate, Taper angle Circularity and Perpendicularity) were obtained considering the significant parameters. The program is developed in MATLAB using Neural Networks based back propagation algorithm and the results are compared with the experimental data. A validated mathematical model will be useful for the Industrial applications to predict the responses without performing unnecessary experiments for AISI A2 tool steel. This leads to increase the performance and economic productivity of drilling EDM process.

Electrical power systems in electrical vehicles require high energy density sources such as battery-ultracapacitor hybrid storage system. In order to draw energy from the source as well as recharging the ultra-capacitor during regenerative breaking, a dual-bridge series resonant DC-to-DC converter with modified gating scheme is proposed. The switches on the primary side of the transformer are controlled using the modified gating scheme, and the switches on the secondary side of the transformer are controlled using normal gating scheme having phase-shift with respect to the primary voltage. The use of modified gating scheme increases the number of switches operating in zero voltage switching, thus increasing the overall efficiency as well as reducing component stress. Moreover, the direction of the power flow is determined by the polarity of the phase shift between the primary and secondary sides of the converter. The proposed converter is analyzed using approximate ac equivalent circuit analysis for both ac impedance load and voltage source load. Based on the analysis, a design procedure and design curves are given. Finally, a 200 W converter with input voltage ranging from 64 V to 96 V and output voltage ranging from 88 V to 104 V is designed, and PSIM simulation and experimental results are shown to verify the theoretical values.