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Sawdust, Rice husk and seashells are bio waste products. The use of bio waste materials to create a useful product is called green manufacturing. Sawdust-reinforced epoxy resin composites give good mechanical and physical properties. The reinforced epoxy resin has excellent mechanical strength, electrical and chemical resistance, good thermal insulation and is used as filler material. Rice husk is one of the waste products while extracting the rice from the paddy. This rice husk is good in adhesive nature, used as a green manure and filler material. Seashell is one of the solid waste materials. These seashells are rich in calcium carbonate, so their strength is high compared with natural fiber. The powdered seashell is added with the sawdust and rice husk epoxy resin composite with three different ratios. The percentage of epoxy resin is maintained at a constant ratio (65%). The combinations are adding sawdust (35%) with epoxy resin (65%), sawdust (20%) and rice husk (15%) with epoxy resin (65%). The final combination of adding all three sawdust (20%), rice husk (10%) and seashell (5%) with epoxy resin (65%). The above composites are fabricated by compression molding techniques. The mechanical properties like tensile, impact, hardness and compressive tests have been investigated. [ABSTRACT FROM AUTHOR]

Inconel-600 superalloys have a number of applications in space and aerospace sector due to its unique characteristics of high strength at elevated temperature, low weight, corrosion resistance and high wear resistance. However, due to these characteristics, Inconel-600 superalloy poses challenges in joining. Therefore, an attempt has been made to resolve these issues using microwave hybrid heating (MHH). The characteristics of the constituents of MHH process have large impact on the welded joint's strength. This paper examines the impact of control parameters on the ultimate tensile strength (UTS) and percentage elongation (EL) of Inconel-600 plates, which are welded via MHH. Design of experiments was carried out in accordance with Taguchi L16 orthogonal array (OA), taking in consideration of filler powder particle size (FPS), susceptor and separator. Multi-performance features were optimized via the effective utilization of Taguchi-based grey relational analysis (GRA) approach. ANOVA results show that the predominating factor to govern the joint strength is FPS followed by the susceptor and separator. The validation experiments are performed on the predicted optimized setting of process parameters. First level of FPS (30µm), second level of susceptor (Graphite) and second level of separator (SiC) were found as the optimized parametric settings. [ABSTRACT FROM AUTHOR]

Inconel-600 superalloys have a number of applications in space and aerospace sector due to its unique characteristics of high strength at elevated temperature, low weight, corrosion resistance and high wear resistance. However, due to these characteristics, Inconel-600 superalloy poses challenges in joining. Therefore, an attempt has been made to resolve these issues using microwave hybrid heating (MHH). The characteristics of the constituents of MHH process have large impact on the welded joint's strength. This paper examines the impact of control parameters on the ultimate tensile strength (UTS) and percentage elongation (EL) of Inconel-600 plates, which are welded via MHH. Design of experiments was carried out in accordance with Taguchi L16 orthogonal array (OA), taking in consideration of filler powder particle size (FPS), susceptor and separator. Multi-performance features were optimized via the effective utilization of Taguchi-based grey relational analysis (GRA) approach. ANOVA results show that the predominating factor to govern the joint strength is FPS followed by the susceptor and separator. The validation experiments are performed on the predicted optimized setting of process parameters. First level of FPS (30μm), second level of susceptor (Graphite) and second level of separator (SiC) were found as the optimized parametric settings. [ABSTRACT FROM AUTHOR]

Austenitic stainless steels are very important material and extensively used for various applications in fertilizer industry, petrochemical industry, nuclear industry and food industry. Austenitic stainless steel 316L alloyed with small percentage of nitrogen is called 316LN. 316LN is widely used only in nuclear applications and it is also called high temperature steels. This nitrogen alloyed steels 316LN will work at higher temperature environment along with radiation environment without losing its properties. The welding of this 316LN steel poses challenge due to problems like sensitization to inter granular corrosion, stress corrosion cracking and even hot cracking. Selecting the type of welding and filler material is more important for welding the 316LN austenitic stainless steel (SS). In this paper SS 316LN material is being welded with TIG and MIG welding. Three pairs of SS 316LN plates were used for experimental work. Filler electrode ER316L is used for TIG and MIG121 is used for MIG welding. After the welding process, hardness test, tensile test and bending test were performed to check the mechanical properties of the specimen. Microstructure of the specimen is observed at the weld region. The results show that the welded joint is stronger than the base material in TIG welding process compared to MIG welding, combination of TIG and MIG welding. Hardness values are observed to be higher at the weld region than the base material. Tensile test results show that the ultimate tensile strength of welded plate is greater than that of base materials and TIG welding process is better than other two processes. The microstructure images show that there is a continuous and uniform welding and the joint is defect free from cracks. [ABSTRACT FROM AUTHOR]

In injection molding, heat transfer at the polymer/mold interface during solidification of the polymer significantly affects the cooling rate, microstructure, and hence the product quality. An accurate estimation of the boundary heat flux transients is essential for the successful simulation of polymer solidification, which can aid in predicting and preventing potential defects that may arise from improper filling and cooling. Simulation studies also help in optimizing the cycle time with different process parameters. In the present work, a pneumatically-operated injection molding machine capable of producing a single component in one cycle was designed and fabricated in-house to estimate the heat flux transients at the polymer/mold interface. The mold used for solidification of the polymer was made from tool steel (P20) with a simple rectangular cavity. The mold was instrumented with thermocouples across the thickness to record its thermal history during injection molding. The polymer/mold interfacial heat flux transients were estimated by solving an inverse heat conduction problem (IHCP). The temperature measured at locations beneath the cavity surface inside the mold was used as an input to the inverse solver. Altering the melt injection and mold temperatures showed negligible effects on heat flux transients at the polymer/mold interface. The estimated solidification time for the polymer sample was about 2 s. [ABSTRACT FROM AUTHOR]

Wildlife tagging provides critical insights into animal movement ecology, physiology, and behavior amid global ecosystem changes. However, the stress induced by capture, handling, and tagging can impact post-release locomotion and activity and, consequently, the interpretation of study results. Here, we analyze post-tagging effects on 1585 individuals of 42 terrestrial mammal species using collar-collected GPS and accelerometer data. Species-specific displacements and overall dynamic body acceleration, as a proxy for activity, were assessed over 20 days post-release to quantify disturbance intensity, recovery duration, and speed. Differences were evaluated, considering species-specific traits and the human footprint of the study region. Over 70% of the analyzed species exhibited significant behavioral changes following collaring events. Herbivores traveled farther with variable activity reactions, while omnivores and carnivores were initially less active and mobile. Recovery duration proved brief, with alterations diminishing within 4–7 tracking days for most species. Herbivores, particularly males, showed quicker displacement recovery (4 days) but slower activity recovery (7 days). Individuals in high human footprint areas displayed faster recovery, indicating adaptation to human disturbance. Our findings emphasize the necessity of extending tracking periods beyond 1 week and particular caution in remote study areas or herbivore-focused research, specifically in smaller mammals. In wildlife tagging, stress from capture and handling can alter post- release behavior and potentially study interpretations. This study of 42 mammal species shows that these effects diminish within 4–7 days, and quicker for animals in high human activity areas indicating adaptation to disturbance. [ABSTRACT FROM AUTHOR]

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Maintaining vacuum integrity for the semiconductor manufacturing processes is extremely important to improve semiconductor fab productivity. The expensive machinery and the enormous costs of production downtime require reliable sealing systems which are designed to operate the longest possible preventative maintenance (PM) cycles. Being able to predict the lifetime of the sealing systems can help determine the optimum maintenance periods and hence increase profitability in costly wafer processing. The present contribution describes a finite element method to predict the lifetime of vacuum sealing systems limited by aging effects of the elastomer. Several different applications are considered including isothermal and non-isothermal conditions. Furthermore, homogeneous and inhomogeneous temperature fields are analyzed. Finally, the model predictions are compared to experimental data. [ABSTRACT FROM AUTHOR]

Boldness – defined as the propensity of individuals to take risks – is a key research area within animal behavioural studies, significantly affecting adaptive strategies, habitat selection, foraging behaviour, reproduction, dispersal, and other crucial survival behaviours. Despite the extensive study of personality traits like extraversion and curiosity across various animal species, data on wolves (Canis lupus), particularly on the subspecies level, remains sparse. This study aims to bridge this gap by examining boldness and its associated personality traits in different wolf subspecies (Canis lupus lupus, Canis lupus arctos, Canis lupus lycaon) (n = 23), and wolf‐dog hybrids (n = 10), utilising novel object interaction tests and validated questionnaires previously applied to wild canids. Our results show significant differences in boldness as well as in related personality traits between taxa, both between pure wolves and wolf hybrids, with significantly higher boldness of North American subspecies. The inter‐subspecies differences were more significant than the differences between groups or at the individual level, suggesting that subspecies ecology and historical selection pressure in subspecies history might have caused long‐lasting adaptations in Canis lupus ssp. [ABSTRACT FROM AUTHOR]

One of theories explaining the development of long-lasting symptoms after an acute severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection include changes in the methylation pattern of the host. The current study aimed to investigate whether DNA methylation levels associated with the angiotensin-converting enzyme 2 (ACE2) promoter are different when comparing individuals previously hospitalized due to COVID-19 who then developed long-lasting post-COVID pain with those previously hospitalized due to COVID-19 who did not develop post-COVID-19 pain symptoms. Non-stimulated saliva samples were obtained from a cohort of 279 (mean age: 56.5, SD: 13.0 years old, 51.5% male) COVID-19 survivors who needed hospitalization. Clinical data were collected from hospital medical records. Participants were asked to disclose pain symptoms developed during the first three months after hospital admission due to COVID-19 and persisting at the time of the interview. Methylations of five CpG dinucleotides in the ACE2 promoter were quantified (as percentages). Participants were evaluated up to 17.8 (SD: 5.3) months after hospitalization. Thus, 39.1% of patients exhibited post-COVID-19 pain. Most patients (77.05%) in the cohort developed localized post-COVID-19 pain. Headache and pain in the lower extremity were experienced by 29.4% of the patients. Seven patients received a post-infection diagnosis of fibromyalgia based on the presence of widespread pain characteristics (11.6%) and other associated symptoms. No significant differences in methylation percentages at any CpG location of the ACE2 promoter were identified when comparing individuals with and without post-COVID-19 pain. The current study did not observe differences in methylation levels of the ACE2 promoter depending on the presence or absence of long-lasting post-COVID-19 pain symptoms in individuals who needed hospitalization due to COVID-19 during the first wave of the pandemic. [ABSTRACT FROM AUTHOR]

Surface grinding experiments are conducted on Compacted Graphite Iron (CGI) GJV450 using a resinoid cubic boron nitride (cBN) wheel. The cutting performance of the dry grinding process is compared to emulsifying oil-based fluid, synthetic oil-based fluid, and synthetic oil-based with exfoliated graphite nano-platelets (xGnP) additives. The study also investigates the influence of longitudinal feed on grinding forces, specific energy, force ratio, surface morphology, and surface roughness. The application of all cooling and lubricating fluids leads to a slight reduction of normal and tangential forces. The synthetic oil-based cooling with xGnP nano-platelet only shows a little improvement in cutting force reduction as a result of a relatively low concentration of nano-particles. The ascending of the longitudinal feed generally introduces a higher surface roughness of the CGI workpiece. The roughness under the emulsifying oil-based condition has a higher value, while the cutting with synthetic oil added xGnP exhibits a better surface finish. [ABSTRACT FROM AUTHOR]

Vibrations are found to be dangerous and reduce the life and reliability of the vehicle. The studies were carried out by many researchers to stiff the structures by increasing the wall thickness of the plates, rubber and to minimize the vibration by increasing the damping coefficient of the rubber materials. The conventional materials indicate an improvement in stiffness, but not satisfying the requirements of the engine vibration at different speed and load standards and also increased the mass of the structure. This research on the engine mount vibration isolation aims at developing an alternative material for the structures which exhibit good damping and stiffness characteristics. In terms of properties such as chemical resistance, ease of production, high strength to weight ratio and damping, composite materials are increasingly used in many engineering application where the vibration is predominant. In this paper, the steel plates are replaced by Al6061-SiC Metal Matrix Composites (MMC) and studies are carried out on the engine mount made of Al6061 MMC structural material and integrated with rubber. The static and dynamic properties of the Al6061MMC-rubber mounts are determined using experimental investigations. The harmonic analysis is also carried out to test the damping characteristics of the mounts. [ABSTRACT FROM AUTHOR]

A mathematical model of physiological pulsatile flow of blood through a stenotic flexible artery in the presence of body acceleration is presented in this paper. Streaming blood is considered as a shear-thinning non-Newtonian fluid as proposed by Yeleswarapu (Evaluation of continuum models for characterizing the constitutive behaviour of blood, Ph.D. thesis, Dept. Mech. Eng., University of Pittsburgh, 1996), and a physiological pulsatile flow rate proposed by Pedrizzetti (J Fluid Mech 310:89–111, 1996) has been taken through the tube. Deformation of vessel wall is modelled as a function of flow rate. This computational study of an idealized model may bring some insights for realistic blood flow through a stenotic artery. The novelty of this work lies in the fact that realistic flow of blood through a stenosed artery has been studied as far as possible and a new idea has been provided to describe the arterial wall motion. Governing equations in cylindrical polar coordinates are solved using stream function–vorticity method. Behaviour of various flow quantities is investigated through a parametric study. It is noted that the degree of constriction and body acceleration have important impacts on the haemodynamic parameters such as wall shear stress, oscillatory shear index, and relative residence time. Increasing body acceleration enhances the peak value of wall shear stress, but reduces the oscillatory shear index and relative residence time. Almost 1/4th increase in length of flow separation is found when Froude number raises its value from 0.1 to 0.5, other parametric values remaining fixed. On the other hand, almost 50% increase in the magnitude of the peak value of wall pressure is found when the amplitude of body acceleration takes a value 0.4 (A = 0.4) compared to the without body acceleration case (A = 0). These results have a significant role. [ABSTRACT FROM AUTHOR]

Provides a listing of current staff, committee members and society officers. [ABSTRACT FROM PUBLISHER]

This paper deals with the observer design for a class of Interconnected Takagi–Sugeno (TS) systems with Immeasurable Premise Variables (IPV). We first investigate the D-stability of Luenberger-like interconnected multiple observers. However, the resulting constraints can be somewhat conservative due to the use of a common Lyapunov matrix. Then, the so-called Finsler's lemma is used to relax the D-stability conditions through the introduction of additional slack variables providing more flexibility and extra degrees of freedom. The designed conditions are expressed as Linear Matrix Inequalities (LMIs). The proposed approaches are applied in simulation to a Proton Exchange Membrane Fuel Cell (PEMFC) system and a four-tank system. [ABSTRACT FROM AUTHOR]

This paper presents a lifting‐line implementation in the framework of a Lagrangian vortex particle method (LL‐VP). The novelty of the present implementation lies in the fluid particles properties definition and in the particles shedding process. In spite of mimicking a panel method, the LL‐VP needs some peculiar treatments described in the paper. The present implementation converges rapidly and efficiently during the shedding sub‐iteration process. This LL‐VP method shows good accuracy, even with moderate numbers of sections. Compared to its panel or vortex filaments counterparts, more frequently encountered in the literature, the present implementation inherently accounts for the diffusion term of the Navier‐Stokes equations, possibly with a turbulent viscosity model. Additionally, the present implementation can also account for more complex onset flows: upstream ambient turbulence and upstream turbine wakes. After validation on an analytical elliptic wing configuration, the model is tested on the Mexnext‐III wind turbine application, for three reduced velocities. Accurate results are obtained both on the analytical elliptic wing and on the New MEXICO rotor cases in comparison with other similar numerical models. A focus is made on the Mexnext‐III wake analysis. The numerical wake obtained with the present LL‐VP is close to other numerical and experimental results. Finally, a last configuration with three tidal turbines in interaction is considered based on an experimental campaign carried out at the IFREMER wave and current flume tank. Enhanced turbine‐wake interactions are highlighted, with favourable comparisons with the experiment. Hence, such turbine interactions in a farm are accessible with this LL‐VP implementation, be it wind or tidal energy field. [ABSTRACT FROM AUTHOR]

This study presents the preliminary outcomes of a methodology for the physical and mechanical characterization of various chestnut elements in different states of preservation. Strategizing conservation and retrofit interventions for timber is necessary, and to do this, it is necessary to establish an estimation of physical (transmissivity, thermal conductivity, humidity level, etc.) and mechanical properties (density, compressive or bending strength, etc.). This essential information is typically associated with timber defects, but there are lack of correlations. The primary objective is to establish correlations between thermal and density properties with the aim of preserving original assets. The investigation delves into the relationship between timber density and thermal properties through experimental non-destructive testing (NDT). Two NDTs were employed with the aim of correlating: penetrometric testing and active thermography investigations. The parametric study on the excitation period yielded valuable insights into the temporal dynamics of heat transfer within the timber, underscoring the significance of selecting appropriate excitation periods to capture precise thermal properties. Tabular data on relative humidity for salified, dried, and new samples provided a quantitative backdrop to these observations, unveiling the nuanced effects of humidity on the timber's thermal response. The results of this study are positioned to inform future conservation efforts by laying the groundwork for a comprehensive understanding of timber's mechanical properties. Particularly, the challenge lies in accurately estimating density, where surface tests are often less reliable than in-depth ones. Therefore, it is crucial to seek validation through other NDT tests, such as thermographic analysis and visual inspection, and hygrometric tests recognizing their importance in enhancing the reliability of density assessments. This approach will contribute to the development of more discerning preservation strategies. [ABSTRACT FROM AUTHOR]

Spiral grains are one of the most important tree growth defects that can remarkably affect the shape stability of lumber. This growth defect is observed by an oblique arrangement of axially oriented cell elements in the wood. This research focused on identifying and measuring selected shape changes caused by the spiral grains in the log. Hornbeam logs with spiral grain and with no spiral grain aged 60 and 52 years were selected to detect shape changes. Following the research and the norms of STN EN 1309-3 (49 1013), DIN (4074-5), and ASTM D245, it can be stated that spiral grain is an essential factor affecting the shape stability of hornbeam lumber. In the case of lumber with spiral grain, the spiral grain increased by up to 8° within three months. The warp of both types (bow, crook) increased exponentially throughout the study, peaking between the third and fourth week with an increase in warp bow of 26 mm and 17 mm in warp crook. [ABSTRACT FROM AUTHOR]

In this research, the Taguchi-based TOPSIS technique was utilized to optimize TIG welding parameters for carbon steel. Five Input factors included welding current CT (80,100 A), gas flow rate GF (10,15 l/min), tip angle TP (30°,60°), Electrode diameter ED (2.4, 3.2 mm) and welding speed WS (100, 150 mm/min) with Taguchi's L12 orthogonal array employed for experimental design. Tests were conducted to evaluate joint hardness and Tensile strength, with specimen assignment based on performance scores via TOPSIS. The ratios of signal to noise for each factor were determined, ranking the welding parameters based on the delta value, in order to evaluate the impact of certain input variables on the output parameters. ANOVA was employed to identify the most significant parameter, and a regression equation was developed to establish a mathematical model correlating the S/N ratio of performance scores with process parameters. Validation was performed through a confirmatory experiment using optimized parameters, yielding results consistent with the proposed approach. TOPSIS identified the combination CT1-GF2-TP1-ED2-WS1 as optimal: 80 A current, 15 l/min gas flow, 60° tip angle, 3.2 mm electrode diameter, and 100 mm/min welding speed. [ABSTRACT FROM AUTHOR]

This study addresses effect of shotpeening on surface characteristics of AA6061-SiCP composite. Aluminium composites with reinforcements of solitary and multiple particles are widely employed in the transportation, aerospace, and automotive sectors due to their exceptional properties, such as strength, stiffness, and wear resistance. However, the surface characteristics such as hardness, wear, and frictional properties are not improved much. To attain better surface properties, surface modification has become necessary. Therefore, shotpeening is employed with selected parameters to analyse surface topography before and after shotpeening using optical and scanning electron microscopes. Then, the average crystalline size (ACS), dislocation densities, and micro-strain are calculated with the X-ray diffraction (XRD) analysis and then correlated with the hardness of shot peened AA6061-SiCP composites in comparison with the untreated surface. The results demonstrate that increasing the shotpeening exposure durations improves surface characteristics compared to untreated AA6061-SiCP composites. At 140 s of exposure time, the micro-hardness is increased to approximately 143HV, crystallite size is refined to approximately 33.7 nm, micro-strain is enhanced by about 3.1 × 10−3, and dislocation density is increased by about 19.2 × 10−14 m−2. Severity of the shotpeening develops severe plastic deformation results in surface fracture and an increase in roughness of AA6061-SiCP composites. [ABSTRACT FROM AUTHOR]

Present study is focused on optimization of WEDM process parameters for increased productivity and improved surface quality of the machined surface of hybrid composite [Al6061 (90 %), SiC (2.5 %) and TiB2 (7.5 %)] by utilizing the trim cut strategy. Effects of four factors namely, pulse on time (Ton), peak current (Ip), wire offset (WO) and rough-cut history (RCH) have been investigated on response characteristics namely, material removal rate (MRR), surface roughness (SR) and Recast layer (RL) thickness; using Box-Behnken design (BBD) for the experimentation. Three levels of RCH i.e., high, medium and low have been included to investigate the effectiveness of trim cut strategy for dealing with rough-cut surface under varied conditions. The optimized parametric setting has been obtained for multiple responses using desirability function. RCH is found to be most significant factor for MRR, while pulse on time (Ton) is found most significant for SR and RL. WO has been found to play an important role in controlling the thickness of RL. It is observed that after trim cut, surface roughness is improved for experiments conducted under high and medium levels of RCH. However, almost no improvement in SR is obtained for low level of RCH. Trim cut strategy is also found to be effective in reducing the thickness of recast layer, however, it is noticed that the percentage reduction in recast layer thickness for samples machined under high level RCH is greater than that for the other two levels of RCH. [ABSTRACT FROM AUTHOR]