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Routing in ad hoc networks faces significant challenges due to node mobility and dynamic network topology. In this work we propose the use of mobility prediction to reduce the search space required for route discovery. A method of mobility prediction making use of a sectorized cluster structure is described with the proposal of the Prediction based Location Aided Routing (P‐LAR) protocol. Simulation study and analytical results of P‐LAR find it to offer considerable saving in the amount of routing traffic generated during the route discovery phase.

In the past, by adopting the handover prediction concept of the fast mobile IPv6, the authors have proposed a cross-layer architecture, which was called the proactive fast HCoP-B (FHCoP-B), to trigger layer 3 HCoP-B route optimization flow by 802.11 and 802.16 link events before the actual layer 2 handover of a mobile subnet in the nested mobile network (NEMO) occurs. In this way, proactive FHCoP-B has shortened its handover latency and packet loss. However, there are two scenarios where proactive FHCoP-B cannot normally complete its operations due to fast movements of the NEMO during handover. The paper aims to discuss these issues.

In this paper, the authors will propose efficient reactive FHCoP-B flows for these two scenarios to support fast and seamless handovers. The authors will further extend the analytical model proposed for mobile IPv6 to investigate four performance metrics of proactive and reactive FHCoP-B, HCoP-B and two well-known NEMO schemes with the radio link protocol (RLP), which can detect packet losses and performs retransmissions over the error-prone wireless link.

Through intensive simulations, the authors conclude that FHCoP-B outperforms HCoP-B and the other two well-known NEMO schemes by achieving the shortest handover latencies, the smallest number of packet losses and the fewest playback interruption time during handover only with few extra buffer spaces, even over error-prone wireless links of the nested NEMO.

This paper has three major contributions, which are rare in the NEMO literature. First, the proactive FHCoP-B has been enhanced as the reactive one to handle two fast handover scenarios with RLP for the nested NEMO. Second, the reactive FHCoP-B supports seamless reactive handover for the nested NEMO over error-prone wireless links. Third, mathematical performance analyses for two scenarios of reactive FHCoP-B with RLP over error-prone wireless links have been conducted.

This paper aims to focus on the utilisation of pre- and probiotics for oral care and the state of knowledge at this time.

Pre- and probiotics describe beneficial carbohydrates and microbiota, respectively, for optimal gut health. Carbohydrates provide energy selectively for the gut-friendly bacteria. The use of both carbohydrates and bacteria is, however, being expanded into other areas of the body – including the skin, vagina and oral cavity – for health-related applications.

There is increased interest in both pre- and probiotics for oral care products. The importance of oral microflora and their selective substrates is discussed against a background of contemporary oral care approaches. The issues and benefits are discussed in this review.

It is clear that consumption of prebiotics and probiotics may play a role as potential prophylactic or therapeutic agents for reducing the presence of organisms in the mouth associated with tooth decay. To confirm a beneficial effect of pre- and probiotics further in vivo studies involving healthy human volunteers should be considered.

There is a need for a realistic simulator to model real mobile networks users. The purpose of this paper is to present a practical approach for simulating mobile networks. It aims to develop a platform that enables researchers to study different mobility scenarios.

The platform is built by using an initial set of real world data which is made richer by adding more complex movement patterns for users. Such an environment will aid researchers that are studying different problems related to users' behavior in a mobile computing setup.

It was found that the illustrative histograms of the generated network are used as an effective tool to modify and qualify the generated network, before actually using it, to have a network as close as possible to a real world one.

The authors were unable to access real data from real networks because of privacy issues.

The paper describes the first fully integrated simulator for mobile networks.

The study aims to verify and establish the result of the most suitable optimization approach for higher performance and lower emission of a variable compression ratio (VCR) diesel engine. In this study, three types of test fuels are taken and tested in a variable compression ratio diesel engine (compression ignition). The fuels used are conventional diesel fuel, e-diesel (85% diesel-15% bioethanol) and nano-fuel (85% diesel-15% bioethanol-25 ppm Al₂O₃). The effect of bioethanol and nano-particles on performance, emission and cost-effectiveness is investigated at different load and compression ratios (CRs). The optimum performance and lower emission of the engine are evaluated and compared with other optimization methods.

The test engine is run by diesel, e-diesel (85% diesel-15% bioethanol) and nano-fuel (85% diesel-15% bioethanol-25 ppm Al₂O₃) in three different loadings (4 kg, 8 kg and 12 kg) and CR of 14, 16 and 18, respectively. The optimum value of energy efficiency, exergy efficiency, NO_X emission and relative cost variation are determined against the input parameters using Taguchi-Grey method and confirmed by response surface methodology (RSM) technique.

Using Taguchi-Grey method, the maximum energy and exergy efficiency, minimum % relative cost variation and NO_X emission are 24.64%, 59.52%, 0 and 184 ppm, respectively, at 4 kg load, 18 CR and fuel type of nano-fuel. Using RSM technique, maximum energy and exergy efficiency are 24.8% and 62.9%, and minimum NO_X emission and % cost variation are 208.4 ppm and –6.5, respectively, at 5.2 kg load, 18 CR and nano-fuel. The RSM is suggested as the most appropriate technique for obtaining maximum energy and exergy efficiency, and minimum % relative cost; however, for lowest possible NO_X emission, the Taguchi-Grey method is the most appropriate.

Waste rice straw is used to produce bioethanol. 4-E analysis, i.e. energy, exergy, emission and economic analysis, has been carried out, optimized and compared.

To study the changes occurring in lac‐polyvinyl butyral (PVB) resin blends at molecular levels on baking the blends at 200°C for different intervals of time. It was also to ascertain the changes in key physico‐chemical parameters of these blends, before and after applying thermal stress on these blends.

Films of lac‐PVB blends, applied on tin panels were baked at 200°C for different time intervals. The FTIR spectra of the blends were recorded using specular reflectance spectroscopic techniques. The results obtained were compared and reported. The blends were also tested for different physico‐chemical parameters such as scratch hardness, flexibility, adhesion, acid resistance, etc.

On baking the blends of lac‐PVB resin at 200°C for different time intervals; fragmentation reaction, that is breakdown of products into small molecules, takes place in lac‐PVB blends. Side products such as acetic acid emerge on baking the blends. Probably hydrolysis of oxirane ring also takes place leading to the release of free alcoholic groups. The lac‐PVB blends do not show any improvement in scratch hardness and are also not resistant to the action of acids. The blends made by lac‐PVB resin baked at 200°C do not seem to be compatible as no improvement in any of the physico‐chemical parameters was seen.

Mixtures of solvents were tried for dissolving the PVB resin. In most of the solvent mixtures, PVB resin forms big lumps and is not soluble so there is a need for universal solvent for dissolving the PVB resin. The spectral studies on lac‐PVB blends were conducted qualitatively, although desirable, quantitative studies could not be carried out, due to the inherent difficulties in handling the resins.

The parent resins in lac‐PVB blends (baked at 200°C) do not seem to be compatible with one another as there was no improvement in any of the physico‐chemical parameters of the lac‐PVB blends. For making lac‐PVB blends, low range of baking temperature may be tried.

In literature, there is not much evidence of making lac‐PVB blends. This paper is the first one in attempting to obtain and correlate FTIR spectra of the lac‐PVB blends with physico‐chemical changes of the blends. This paper also highlights the convenience of the method and the scope of sophisticated data analysis such as derivative spectrometry.

The purpose of this paper is to unfold the perceptions around additional security in cloud environments by highlighting the importance of controlling mechanisms as an approach to the ethical use of the systems. The study focuses on the effects of the controlling mechanisms in maintaining an overall secure position for the cloud and the mediating role of the ethical behavior in this relationship.

A case study was conducted, examining the adoption of managed cloud security services as a means of control, as well as a large-scale survey with the views of IT decision makers about the effects of such adoption to the overall cloud security.

The findings indicate that there is indeed a positive relationship between the adoption of controlling mechanisms and the maintenance of overall cloud security, which increases when the users follow an ethical behavior in the use of the cloud. A framework based on the findings is built suggesting a research agenda for the future and a conceptualization of the field.

One of the major limitations of the study is the fact that the data collection was based on the perceptions of IT decision makers from a cross-section of industries; however the proposed framework should also be examined in industry-specific context. Although the firm size was indicated as a high influencing factor, it was not considered for this study, as the data collection targeted a range of organizations from various sizes.

This study extends the research of IS security behavior based on the notion that individuals (clients and providers of cloud infrastructure) are protecting something separate from themselves, in a cloud-based environment, sharing responsibility and trust with their peers. The organization in this context is focusing on managed security solutions as a proactive measurement to preserve cloud security in cloud environments.

The purpose of this paper is to provide strategic recommendations to supply chain managers of Indian manufacturing industries for a robust supply chain related to risk management by original equipment manufacturers (OEMs) and suppliers in manufacturing industries to ensure a robust supply chain risk management (SCRM).

Importance-performance analysis (IPA) is utilized to identify and provide strategic recommendations to manufacturing industries for improving their supply chain performance by attaching due importance to risk constructs and appropriately choosing mitigation strategies.

The investigation using the strategic action grids reveals that most of the means of risks are near the point of intersection of the grand means of the risk constructs and their impact on the supply chain, indicating that all the risks have the equal likelihood of occurrence. The mean importance of risk monitoring, risk avoidance (RA) and risk sharing surpass the mean performance for both OEMs and suppliers.

The study is executed with following limitations: the study assumes that the manufacturing industries across different sectors perceive similar risk. The sectors considered are automotive, heavy engineering, general engineering and home appliances. The Southern States of India are considered because of the dominant presence of many industries, especially automotive industries. However, it should be noted that these States form the manufacturing hubs where the lead organizations are functioning along with their major suppliers.

By understanding the importance of SCRM dimensions and utilization of these dimensions, firms can mitigate the impact of risk on the supply chain. The detailed study of SCRM strategies highlights the importance attached to risk factors, mitigation strategies, and top management commitment. By the implementation of SCRM strategies, supply chain managers can improve the firm’s performance.

The study involves empirically validated data on SCRM dimensions. The IPA is performed on the SCRM dimensions to investigate the importance attached to the factors of the dimensions and their performance.

The purpose of this paper is to harness the potential of microwave pre-treatment to prepare carbon from locally available Sterculia foetida fruit shells for adsorption of heavy metals, particularly Nickel ions (Ni++), from effluent.

The pre-treatment methods comprise conventional methods as sun drying and oven drying as well as high intensity microwave drying. Response surface methodology was employed to analyse the optimization of the process. The adsorption behavioural characteristics of the material were established applying adsorption isotherms.

Adsorption of Ni++ was found to be effective in microwave drying at output power of 300 W. It was observed that the maximum adsorption capacity was attained at pH 6; an adsorbent dosage of 0.25 mgml−1 and initial metal ion concentration of 20 ppm with an interactive effect of initial concentration and dosage.

The research puts emphasise on prospecting of novel biomass for carbonization and application of the same for effective adsorption. Available literature on Sterculia foetida is very limited and this work will serve to create database on the amenability of processing.

This paper aims to study the mathematical modeling of passive cooling systems for electronic devices. Improving heat transfer is facilitated by the correct choice of the working fluid and the geometric configuration of the engineering cavity; therefore, this work is devoted to the analysis of the influence of the position of the heat-generating element and the tilted angle of the electronic cabinet on the thermal convection of a non-Newtonian fluid.

The area of interest is a square cavity with two cold vertical walls, while the horizontal boundaries are adiabatic. An element of constant volumetric heat generation is placed on the lower wall of the chamber. The problem is described by Navier–Stokes partial differential equations using dimensionless stream function and vorticity. The numerical solution is based on the developed computational code using the finite difference technique and a uniform rectangular grid.

The key conclusions of this work are the results of a detailed analysis of streamlines and isotherms, the average Nusselt number and profiles of the average heater temperature. It was found that more intensive cooling of the heat-generating element occurs when the cavity is filled with a pseudoplastic fluid (n < 1) and not inclined (α = 0). The Rayleigh number of Ra = 10⁵ and the thermal conductivity ratio of k = 100 are characterized by the most positive effect.

The originality of the research lies in both the study of thermal convection in a square chamber filled with power-law fluid under the influence of a volumetric heat production element and the analysis of the influence of geometric and thermophysical parameters characterizing the considered process.