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This paper aims to review the licensing in India, including the development of universal licences and of the now infamous 2G spectrum scam.

This paper is a case study drawing on a side range of official documents, including inquiry reports, policies, licences and court judgements.

Liberalisation of the sector introduced opportunities for lobbying and corruption that lead to very unusual market structures, with many operators and too little spectrum.

Interviews with the principals were impossible.

It is now necessary for the government to adopt good governance processes, especially in respect of 4G and th inevitable consolidation of operators in a fair and equitable manner.

The governance systems are incapable of controlling the corruption in the telecommunications sector and require substantial redesign.

The paper is the first to relate corporate political activity and corruption to outcomes in the telecommunications sector in India.

In 2011, the Malaysian cabinet approved the policy that all board of directors of companies listed on the Bursa Malaysia should consist of 30 per cent women in decision-making positions by the year 2016. The purpose of this paper is to examine the association between the presence of women on the board and firms’ performance following the introduction of the diversity policy.

The analysis uses the information of the top 200 Malaysian public listed companies for the financial year 2011–2013. The multiple regression analysis is used to estimate the relationship between the firm performance (return on assets (ROA)) as the dependent variable and the independent variables.

The results show that during the period under study, the proportion of women directors on board is negatively correlated with ROA. This indicates that the firm performance may not be dependent on the number of women directors on board. However, the results of the study also show that the academic backgrounds of the women board members add some value toward generating better firm performance.

A small sample size of only the top 200 public listed companies was utilised. Consequently the outcome may not be generalisable to smaller public companies or private firms. Another limitation is regarding the sample period. Taking only one year before and one year after the policy’s approval may be too short of the period under study and may be too early to study the impact of the policy. Future studies could sample a longer period.

The findings encourage public listed companies to appoint women with the necessary qualities as members of the board and not to simply increase the number of women on boards.

There is a lack of work on studying women’s effectiveness on board in developing countries, whereby previous work and literature review were predominantly based upon the experience of Western economies. This study, thus, contributes to the rising literature on women board member representation based on the firm performance of the top 200 listed companies in Malaysia.

The purpose of this paper is to evaluate the influence of temperature, load and sliding speed on wear and friction behavior of LM25/SiC composites in as-cast and heat-treated conditions.

The LM25/SiC aluminum matrix composites (AMCs) were prepared using the stir casting process. The wear tests were carried out using a pin-on-disc setup in dry condition. The three levels of each parameter, i.e. 100, 150 and 200°C operating temperature; 15, 25 and 35 N load; 0.8, 1.6 and 2.4 m/sec sliding speed, were considered for the investigation. ANOVA has been carried out to evaluate the percentage contribution of parameters. Scanning electron microscope analysis of worn surfaces has been carried out to understand the wear mechanism.

The wear and coefficient of friction (COF) increase with the increase in the temperature, load and sliding speed within a selected range for as-cast as well as heat-treated LM25/SiC AMCs. The mean values of wear and COF in heat-treated samples were found to be lower than as-cast samples for all cases. It was observed that the percentage wear increases significantly as temperature increases in as-cast AMCS. Mild to severe wear transition was observed at 150°C. In heat-treated AMCs, mild wear was observed irrespective of temperature. It was also observed that as the temperature increases, transition of wear mechanism from abrasive to adhesive (including delamination) occurs earlier in as-cast samples as compared to heat-treated samples.

There is a lack of data on combined effect of temperature, load and sliding speed on tribological aspects of as-cast and heat-treated LM25/SiC AMCs, limiting its applications. The present research work has addressed this gap.

The majority of the synthetic dyes have been found to be non-biodegradable, toxic and carcinogenic. As a result, there has been a growing trend toward the use of natural dyes as alternates to synthetic dyes. This shift calls for more research to come up with more sources of natural dyes to satisfy their increasing demand. Euclea divinorum plant has been used traditionally as a source of dye, however, its textile dyeing properties have not been studied. This study aims to determine the textile dyeing properties of E. divinorum extract.

Optimization of dyeing conditions of Euclea divinorum natural dye extract on the cotton fabric was done using response surface methodology (RSM). The combined effects of examined dyeing conditions on the relative color strength (K/S) were studied using a central composite experimental design. Analysis of variance (ANOVA) was used to determine the significance of the statistical model generated for the study. Mordanting effects were measured using standard ISO wash, rub and lightfastness tests.

The optimum dyeing conditions were found to be 68 min, pH 3.3 and 82°C with color strength 0.609. Temperature and pH showed some interaction effects during the dyeing experiments. The predicted optimum K/S value was validated experimentally using the optimum conditions and was found to be in agreement with the experimental values. All the metallic mordants used enhanced the color strength and provided a variety of brown shades, therefore, a suitable alternative for the toxic synthetic dyes.

Optimization of dyeing conditions of Euclea divinorum dye on cotton using RSM and mordanting at optimal conditions has not been done elsewhere.

One of the major challenges in the design of thermal equipment is to minimize the entropy production and enhance the thermal dissipation rate for improving energy efficiency of the devices. In several industrial applications, the structure of thermal device is cylindrical shape. In this regard, this paper aims to explore the impact of isothermal cylindrical solid block on nanofluid (Ag – H₂O) convective flow and entropy generation in a cylindrical annular chamber subjected to different thermal conditions. Furthermore, the present study also addresses the structural impact of cylindrical solid block placed at the center of annular domain.

The alternating direction implicit and successive over relaxation techniques are used in the current investigation to solve the coupled partial differential equations. Furthermore, estimation of average Nusselt number and total entropy generation involves integration and is achieved by Simpson and Trapezoidal’s rules, respectively. Mesh independence checks have been carried out to ensure the accuracy of numerical results.

Computations have been performed to analyze the simultaneous multiple influences, such as different thermal conditions, size and aspect ratio of the hot obstacle, Rayleigh number and nanoparticle shape on buoyancy-driven nanoliquid movement, heat dissipation, irreversibility distribution, cup-mixing temperature and performance evaluation criteria in an annular chamber. The computational results reveal that the nanoparticle shape and obstacle size produce conducive situation for increasing system’s thermal efficiency. Furthermore, utilization of nonspherical shaped nanoparticles enhances the heat transfer rate with minimum entropy generation in the enclosure. Also, greater performance evaluation criteria has been noticed for larger obstacle for both uniform and nonuniform heating.

The current numerical investigation can be extended to further explore the thermal performance with different positions of solid obstacle, inclination angles, by applying Lorentz force, internal heat generation and so on numerically or experimentally.

A pioneering numerical investigation on the structural influence of hot solid block on the convective nanofluid flow, energy transport and entropy production in an annular space has been analyzed. The results in the present study are novel, related to various modern industrial applications. These results could be used as a firsthand information for the design engineers to obtain highly efficient thermal systems.

Fracture properties depend on the type of material, method of testing and type of specimen. The purpose of this paper is to evaluate fracture properties by adopting a stable test method, i.e., wedge split test.

Coarse aggregate of three different sizes (20 mm, 16 mm and 12.5 mm), three ratios of coarse aggregate, fine aggregate (CA:FA) (50:50, 45:55, 40:60), presence of steel fibers, and specimens without and with guide notch were chosen as parameters of the study.

Load-crack mouth opening displacement curves indicate that for both fibrous and non-fibrous mixes, higher volume of aggregate and higher size of coarse aggregate have high fracture energy.

For all volumes of coarse aggregate, it was noticed that specimens with 12.5 mm aggregate size achieved highest peak load and abrupt drop post-peak. The decrease in coarseness of internal structure of concrete (λ) resulted in the increase of fracture energy.

This paper aims to identify the nature of the problem of corruption in the telecommunications sector and to identify possible actions to limit it.

A review of instances of corruption, showing the scope of its various forms, with particular emphasis on the Arab states, in the light of recent events.

Policies were advocated for telecommunications that greatly increased the risks of corruption without corresponding measures to ensure integrity, transparency and the investigation and prosecution of those paying and, especially, those accepting bribes.

There is a need for much more raw data and detailing of specific cases, in particular there are no plausible estimates of the overall scale of bribery in the sector.

By repressing bribery in telecommunications it will increase competition in markets, reduce prices and remove the social grievance of “crony capitalism”.

There are, as yet, very few articles analysing the effects of corruption in telecommunications or identifying possible courses of action.

The purpose of this paper is to study and analyse the authorship pattern, degree of collaboration, prepare list of prolific authors and test Lotka’s law of scientific productivity in spacecraft technology research.

Data are collected from the print versions of three journals in the field of spacecraft technology for the period 2001-2011. In all 154 volumes containing 1,907 papers have been analysed, and data are presented in different table headings.

Study reveals that 4,355 authors have contributed 1,907 papers. Journal of Spacecraft and Rockets has published maximum (1,487) number of papers during the study period. Multi-authored papers with 87.15 per cent of contributions have dominated this field of research. Journal of Spacecraft Technology has recorded highest degree of collaboration of 0.90. James M. Longuski has published 20 papers in Journal of Spacecraft and Rockets during the period 2001-2011. Lotka’s law of scientific productivity is tested and conforms only partially.

Study is restricted only for the period 2001-2011, and the data are collected from the print versions of three journals in the field of spacecraft technology research.

As far as space science and technology is concerned, there are not many bibliometric studies reported in the published literature. The present study will add value to the bibliometrics literature and provide publishing trends in spacecraft technology research.

The purpose of this study is to provide that porous media and viscous dissipation are crucial considerations when working with hybrid nanofluids in various applications.Recent years have witnessed significant progress in optimizing these fluids for enhanced heat transfer within porous (Darcy–Forchheimer) structures, offering promising solutions for various industries seeking improved thermalmanagement and energy efficiency.

The first step is to transform the original partial differential equations into a system of first-order ordinary differential equations (ODEs). The fourth-order Runge–Kutta method is chosen for its accuracy in solving ODEs. The present study investigates the free convective boundary layer flow of hybrid nanofluids over a moving thin inclined needle with the slip flow brought about by inclined Lorentz force and Darcy–Forchheimer porous matrix, viscous dissipation.

It is found that slip conditions (velocity and Thermal) exist for a range of the natural convection boundary layer flow. In the hybrid nanofluid flow, which consists of Al₂O₃ and Fe₃O₄ are nanoparticles, H₂O − C₂H₆O₂ (50:50) are considered as the base fluid. The consequence of the governing parameter on the momentum and temperature profile distribution is graphically depicted. The range of the variables is 1 ≤ M ≤ 4, 1 ≤ d ≤ 2.5, 1 ≤ δ ≤ 4, 1 ≤ Fr ≤ 7, 1 ≤ Kr ≤ 7 and 0.5≤λ ≤ 3.5. The Nusselt number and skin friction factors are used to calculate the numerical values of various parameters, which are displayed in Table 4. These analyses elucidate that upsurges in the value of the Fr noticeably diminish the momentum and temperature. It is investigated to see if the contemporary results are in outstanding promise with the outcomes reported in earlier works.

The results can be very helpful to improve the energy efficiency of thermal systems.

The hybrid nanofluids in heat transfer have the potential to improve the energy efficiency and performance of a wide range of systems.

This study proposes that in the combined effects of hybrid nanofluid properties, the inclined Lorentz force, the Darcy–Forchheimer model for porous media and viscous dissipation on the boundary layer flow of a conducting fluid over a moving thin inclined needle. Assessing the potential practical applications of the hybrid nanofluids in inclined needles, this could involve areas such as biomedical engineering, drug delivery systems or microfluidic devices. In future should explore the benefits and limitations of using hybrid nanofluids in these applications.

The application of thermal barrier coatings (TBCs) allows aero-engine blades to operate at higher temperatures with higher efficiency. The preparation of the TBCs increases the surface roughness of the blade, which impacts the thermal cycle life and thermal insulation performance of the coating. To reduce the surface roughness of blades, particularly the blades with small size and complex curvature, this paper aims to propose a method for industrial robot polishing trajectory planning based on on-site measuring point cloud.

The authors propose an integrated robotic polishing trajectory planning method using point cloud processing technical. At first, the acquired point cloud is preprocessed, which includes filtering and plane segmentation algorithm, to extract the blade body point cloud. Then, the point cloud slicing algorithm and the intersection method are used to create a preliminary contact point set. Finally, the Douglas–Peucker algorithm and pose frame estimation are applied to extract the tool-tip positions and optimize the tool contact posture, respectively. The resultant trajectory is evaluated by simulation and experiment implementation.

The target points of trajectory are not evenly distributed on the blade surface but rather fluctuate with surface curvature. The simulated linear and orientation speeds of the robot end could be relatively steady over 98% of the total time within 20% reduction of the rest time. After polishing experiments, the coating roughness on the blade surface is reduced dramatically from Ra 7–8 µm to below Ra 1.0 µm. The removal of the TBCs is less than 100 mg, which is significantly less than the weight of the prepared coatings. The blade surface becomes smoothed to a mirror-like state.

The research on robotic polishing of aero-engine turbine blade TBCs is worthwhile. The real-time trajectory planning based on measuring point cloud can address the problem that there is no standard computer-aided drawing model and the geometry and size of the workpiece to be processed differ. The extraction and optimization of tool contact points based on point cloud features can enhance the smoothness of the robot movement, stability of the polishing speed and performance of the blade surface after polishing.