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The purpose of this paper is to discuss how to plan and provide for people's relaxation and engagement, cognitive and aesthetic needs. Symbolic of this is the green city image, which is obtained through planning and management of parks and green areas.

The approach here is to note that Bangalore has gained all‐round importance as an administrative, trading and industrial center and a location for premier educational institutions along with large IT and BT industries. Also, it is a center of strategic importance, due to a concentration of defense establishments. The study observes the abundance of parks and avenue trees and green areas along with green median and traffic islands all through in the city, which provide shade and meet the purely ecological and aesthetic needs.

The study reveals the beneficial impact of green areas on the microclimate of the city, which also serve as outdoor recreation areas to the city people. The parks and green areas need serious rejuvenation as centers of social activity and they should cater to peoples' active and passive recreation needs and abate the stress of urban living.

The implication of this study is the manifest importance of different local government authorities, institutional arrangements, NGOs with expertise to maintain parks and green areas in and around the Bangalore Metropolitan Area and of growing more trees and developing greeneries within the city of Bangalore.

This paper's value is to promote awareness regarding the complexities and importance of parks and green areas and their vulnerabilities and management.

The purpose of this paper is to build up perspectives for the conservation and restoration of the various spoilt water bodies within the Bangalore metropolitan area.

This paper describes how Bangalore city is typical of the features of peninsular India in that it is made up of ridges, valleys and undulating terrain. Monsoon rainfall is substantial and the tanks and lakes can receive and contain substantial amounts of water from rains. Only thing is to de‐clog the natural water flow routes and to restore the bunds of tanks and repair the spillways and put in place legal and administrative measures to preserve the interiors of tanks; free them from construction activities and launch suitable afforestation programs to contain soil erosion, improve the quality of subsoil water and raise if possible medicinal and ornamental trees so that Bangalore gains in its aesthetic appeal.

The study reveals that the existence of water bodies is an important asset to the environment of Bangalore. It has a beneficial impact on the microclimate of the city and serves as outdoor recreational areas, which are very much needed as a source of change and relief for the city dwellers. It is good for developing open spaces with greenery along the valleys. There is much scope for water‐front developments to enhance urban aesthetics in the surrounding areas. It is possible to improve the ground water table, so that there will be scope for tapping ground water through bore wells all through the year, particularly during summers.

This work will draw the attention of government authorities as well as local residents, NGOs and experts to keep the tanks/lakes conserved in and around the BMA and to prevent silting of tanks by offshore development and large‐scale tree planting and also removal of encroachments within the study area.

This study will stimulate interest in recreation, conservation, open space beautification, pollution abatement and a myriad other ways to improve the quality of urban environment.

This paper aims to highlight the contribution of ecological fairs to the promotion of sustainability in university campuses, based on a case study carried out at the University of Passo Fundo, located in Southern Brazil.

Producers and consumers of the ecological fairs were interviewed to analyse how the social, economic and environmental spheres of sustainable development are impacted by these fairs. In total, 24 interviews were conducted.

The results showed how fairs positively impact the academic and local community while bringing sustainability into university campuses.

The main limitations of this study were the number of interviews and the short period during when the study was conducted.

This case study demonstrated how the promotion of ecological fairs on a university campus plays an important role in the implementation and practice of sustainability and can serve as an example for other institutions that intend to work on similar projects.

This paper contributes to the literature by providing a discussion on how ecological fairs represent a good addition in the process of universities to become more sustainable and which aspects of each sustainability sphere are involved.

The purpose of this paper is to investigate the impact of thermal radiation interaction with Hall current, buoyancy force, and oscillatory surface temperature on hydromagnetic-mixed convective heat exchange stream of an electrically conducting nanofluid past a moving permeable plate in a porous medium within a rotating system.

Analytical closed-form solutions are obtained for both the momentum and the energy equations using the perturbation method.

The effects of various important parameters on velocity and temperature fields within the boundary layer are discussed for three different water-based nanofluids containing copper (Cu), aluminum oxide (Al₂O₃), and titanium dioxide (TiO₂) as nanoparticles. Local skin friction and Nusselt number are illustrated graphically and discussed quantitatively. The results show that Hall current significantly affects the flow system. Results for some special cases of the present analysis are in good agreement with the existing literature.

The problem is relatively original to study the hydromagnetic-oscillatory flow of a nanofluid with Hall effect and thermal radiation past a vertical plate in a rotating porous medium.

Aluminium alloys are frequently applied in automotive and other industries, since they provide mass reduction. Besides positive effects, aluminium alloys have their shortcomings reflected, first of all, in inappropriate tribological properties of these materials. The aim of this research was to enable the production of cheap aluminium alloy matrix composite with favourable combination of structural, mechanical and tribological properties, focusing on the tribological behaviour.

The A356 Al-Si alloy was used as a matrix for producing metal matrix composites in compocasting process. Three different materials, in form of particles, were added to the matrix (Al₂O₃, SiC and graphite). Hardness and tribological properties (wear, friction and wear mechanism) of heat-treated (T6) samples were examined and compared. Tribological tests were carried out on ball-on-block tribometer under dry sliding conditions. Sliding was linear (reciprocating). Counter body was alumina ball. Average velocity was 0.038 m/s (max. 0.06 m/s), sliding distance was 500 m and normal load was 1 N.

The effect of two different ceramic particles and graphite particles on tribological properties of obtained composites was evaluated. Wear resistance of composites reinforced with SiC particles was higher and coefficient of friction was lower compared to the composite reinforced with Al₂O₃ particles. A dual hybrid composite (with SiC and graphite particles) showed the lowest value of wear rate and friction coefficient. Dominant wear mechanism for all tested material was adhesion.

It seems useful to continue the work on developing hybrid composites containing soft graphite particles with A356 Al-Si alloy as matrix. The major task should be to improve particles distribution (especially with higher graphite content) and to explore tribological behaviour in diverse working conditions.

Particulate composites with A356 aluminium alloy as a matrix produced in compocasting process using ceramic particles (Al₂O₃, SiC) were investigated in many researches, but there are only few detailed analyses of dual composites (with the addition of ceramic and graphite particles). In some previous studies, it was shown that compocasting process, as relatively cheap technology, can obtain good structural and mechanical characteristics of composites. In this study, it was shown that even a low graphite content, under specified conditions, can improve tribological properties.

The purpose of this paper is to present a numerical investigation on pulsating heat pipe (PHP) to study the slug velocities as a function of various parameters.

The governing equation of PHP is solved using explicit embedded Runge‐Kutta method, the Dormand–Prince pair in conjunction with MATLAB with the nomenclature 45 for the determination of displacement and the velocity of the slug.

The results show that lower fill ratio, higher diameter, higher operating temperature and higher temperature difference between evaporator and condenser for a given working fluid results in higher slug velocities, indicating higher momentum transfer and hence better heat transport.

Under steady state conditions, the design of a PHP is facilitated through the introduction of non‐dimensional numbers.

The displacement and slug velocities for additional working fluids, namely ethanol and methanol, are determined for the first time. The behaviour of non‐dimensional numbers, i.e. Poiseuille number, capillary number and Eckert number in a PHP as a function of various parameters have been studied for the first time.

This paper aims to investigate the wear behaviors of aged metal matrix composites and of the as-cast Al-Si alloy by using a pin-on-disk wear testing machine at room temperature.

Hypoeutectic (Al-7Si) alloy reinforced with low volume fractions of SiC particles (SiC_p) and graphite (Gr) particles were prepared by the stir-casting process. It was found that the addition of 9 Wt.% of SiC_p and 3 Wt.% of Gr particles conferred a beneficial effect in reducing the wear rate of the composites.

The worn-out surfaces of the specimens were examined using scanning electron microscopy (SEM); the extensive micro cracking occurs on the surface of the Al-7Si alloy tested at lower loads. The growth of these microcracks finally led to the delamination of the base alloy surface. The reinforcements (SiCp and Gr) particles tended to reduce the extent of plastic deformation in the surface layer, thereby reducing extensively the occurrence of micro cracking in the composites.

From the results, it is revealed that the quantity of wear rate was less for aged specimens compared to the as-cast specimens. The worn-out surfaces were studied using electron dispersive spectroscopy, and wear debris was analyzed using SEM.

The purpose of this paper is to develop hybrid aluminum metal matrix composite by stir casting process, reinforced with graphite and hard boron carbide particles to enhance the wear resistance. An attempt is made to optimize the wear (weight loss) and coefficient of friction (COF) by considering three factors, i.e. normal load, track diameter and sliding speed which were varied at three different levels.

The effect of graphite and boron carbide on microhardness was studied by adding them in varying percentages. After determining the best combination of hybrid reinforcements, optimization of wear (weight loss) and COF was carried out at various levels of considered factors. Taguchi design of experiments was used using the software “Minitab 16.1”. ANOVA was used to analyze the effect of various parameters on wear and COF. To validate the results, mathematical modeling was carried out in terms of regression equations and results obtained by regression equations.

The results revealed that the lower weight percentage of graphite (3 per cent) and boron carbide (1 per cent) significantly improved microhardness of developed composites. Results of ANOVA revealed that normal load was the main contributing factor for wear and COF. The results obtained by regression equations and confirmatory tests were within the results obtained by ANOVA.

To the best of the author’s knowledge, very less work has been reported on optimization of wear and COF using hybrid reinforcement particles of graphite and boron carbide.

The main purpose of this study is to present a non-similar analysis of two-dimensional boundary layer flow of non-Newtonian nanofluid over a vertical stretching sheet with variable thermal conductivity. The Sisko fluid model is used for non-Newtonian fluid with an exponent (n* > 1), that is, shear thickening fluid. Buongiorno model for nanofluid accounting Brownian diffusion and thermophoresis effects is used to model the governing differential equations.

The governing boundary layer equations are converted into nondimensional coupled nonlinear partial differential equations using appropriate transformations. The resultant differential equations are solved numerically using implicit finite difference scheme in association with the quasilinearization technique.

This analysis shows that the temperature raises for thermal conductivity parameter and velocity ratio parameter while decreases for the thermal buoyancy parameter. The thermophoresis and Brownian diffusion parameter that characterizes the nanofluid flow enhances the temperature and reduces the heat transfer rate. Skin friction drag can be effectively reduced by proper control of the values of thermal buoyancy and velocity ratio parameter.

The wall heating and cooling investigation result in the analysis of the control parameters that are related to the designing and manufacturing of thermal systems for cooling applications and energy harvesting. These control parameters have practical significance in the designing of heat exchangers and solar thermal collectors, in glass and polymer industries, in the extrusion of plastic sheets, the process of cooling of the metallic plate, etc.

To the best of authors’ knowledge, it is found from the literature survey that no similar work has been published which investigates the non-similar solution of Sisko nanofluid with variable thermal conductivity using finite difference method and quasilinearization technique.

This research aims to describe the influence of weight per cent of graphite (Gr), applied load and sliding speed on the wear behavior of aluminum (Al) alloy A356 reinforced with silicon carbide (SiC) (10 Wt.%) and Gr (1 Wt.% and 5 Wt.%) particles. The objective is to analyze the effect of the aforementioned parameters on a specific wear rate.

These hybrid composites are obtained by means of the compo-casting process. Tribological analyses were conducted on block-on-disc tribometer at three different loads (10, 20 and 30 N) and three different sliding speeds (0.25, 0.5 and 1 m/s), at the sliding distance of 900 m, in dry sliding wear conditions. Optimization of the tribological behavior was conducted via the Taguchi method, and ANOVA was used for the analysis of the specific wear rate. Confirmation tests are used to foresee and check the experimental results. Examined samples were analyzed via a scanning electron microscope (SEM). Regression models for predicting specific wear rate were developed with Taguchi and ANN (artificial neural network) methods.

The biggest impact on value of specific wear rate has the load (43.006%), while the impact of Wt.% Gr (31.514%) was less. After comparison of the results, i.e. regression models, for predicting the specific wear rate, it was observed that ANN was more efficient than the Taguchi method. The specific wear rate of Al alloy A356 with SiC (10 Wt.%) and Gr (1 Wt.% and 5 Wt.%) decreases with a decrease in the load and weight per cent of Gr-reinforcing material, as well as with a decrease in sliding speed.

The results obtained in this paper using the Taguchi method and the ANN method are useful for improving and further investigating the wear behavior of the SiC- and Gr-reinforced Al alloy A356.