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This paper aims to design a most demanding low profile and compact ultra-wide band (UWB) antenna system for various wireless applications. The performance (in terms of data rate) of UWB system is improved by using multiple-input-multiple-output (MIMO) technology with it. Owing to the overlap of other existing licensed bands with that of UWB, electromagnetic signals can interfere. So, notched band UWB MIMO antenna system reported here which is highly compact, bandwidth efficient, superior data rate and high inter-element isolation comparatively to other reported designs.

A 49 × 49 × 1.6 mm³ quad-port UWB MIMO antenna with specific bandwidth elimination property is designed. The proposed planar MIMO configuration comprises unique four identical “Cordate-shaped” monopole radiators fed by 2.3-mm thick microstrip-lines. The radiators are located right-angled to each other to enhance inter-element isolation. Further, a different approach of slitted-substrate is applied to minimize the overall size and mutual coupling of the MIMO antenna, as a substitute of decoupling and matching structures. The defected ground structure is used to obtain −10 dB impedance bandwidth in entire UWB band, without compromising with the lower cut-off frequency response. Further, to eliminate the undesired resonant band (WLAN at 5.5 GHz) from UWB, a rounded split ring resonator is introduced in monopole patch.

In the entire operating band of 2.8 to 11 GHz, isolation among elements is more than 24 dB, envelope correlation coefficient less than 0.002, diversity gain greater than 9.99 dB and TARC less than −7 dB are obtained at all 4-ports.

The measured parameters of the fabricated prototype antenna on FR4 substrate are found in good agreement with the simulated results. The small variation in software results and hardware results are observed due to hardware design limitations.

The proposed design may be used for any wireless application following in the range of UWB.

It can be shown from graphs of measured parameters of the fabricated prototype antenna. They found to be in good agreement with the simulated results.

Quantum-dot cellular automata (QCA) is a promising technology, which seems to be the prospective substitute for complementary metal-oxide semiconductor (CMOS). It is a high speed, high density and low power paradigm producing efficient circuits. These days, most of the smart devices used for computing, make use of random access memory (RAM). To enhance the performance of a RAM cell, researchers are putting effort to minimize its area and access time. Multilayer structures in QCA framework are area efficient, fast and immune to the random interference. Unlike CMOS, QCA multilayer architectures can be designed using active components on different layers. Thus, using multilayer topology in the design of a RAM cell, which is not yet reported in the literature can improve the performance of RAM and hence, the computing device. This paper aims to present the modular design of RAM cell with multilayer structures in the QCA framework. The fundamental modules such as XOR gate, 2:1 multiplexer and D latch are proposed here using multilayer formations with the goal of designing a RAM cell with the provision of read, write, set and reset control.

All the modules used to design a RAM cell are designed using multilayer approach in QCA framework.

The proposed multilayer RAM cell is optimized and has shown an improvement of 20% in cell count, 30% in area, 25% in area latency product and 48.8% in cost function over the other efficient RAM designs with set/reset ability reported earlier. The proposed RAM cell is further analyzed for the fault tolerance and power dissipation.

Due to the multilayer structure, the complexity of the circuit enhances which can be eliminated using simple architectures.

The performance metrics and results obtained establish that the multilayer approach can be implemented in the QCA circuit to produce area efficient and optimized sequential circuits such as a latch, flip flop and memory cells.

The purpose of this paper is to propose an analytical model for estimating propagation delay in coupled resistance-inductance-capacitance (RLC) interconnects.

With higher frequency of operation, longer length of interconnect and fast transition time of the signal, the resistor capacitor (RC) models are not sufficient to estimate the delay accurately. To mitigate this problem, accurate delay models for coupled interconnects are required. In this paper, an analytical model for estimation of interconnect delay is developed for simultaneously switching lines. Two distributed RLC lines coupled inductively and capacitively are considered. To validate the proposed model, SPICE results are compared with the proposed analytical results. Each line in the coupled structure is terminated by a capacitive load of 30fF. The driving signal is considered symmetrical with equal rise and fall time of 5 ps and OFF/ON time of 45 ps. The model is validated for both in-phase and out of phase switching of lines.

It is observed that the model works well for both the phases of inputs switching. The derived expressions of delay exhibit complete physical insight, and the results obtained are in excellent agreement with SPICE results. Comparison of analytical delay with SPICE delay shows an average error of < 2.7 per cent.

The analytical expressions for interconnect delay are derived for the first time under simultaneously switching scenario. This model is useful to estimate delay across the inductively and capacitively coupled interconnects.

The purpose of this research paper is to analyze the combined effects of driver size and coupling parasitics on crosstalk noise and delay for static and dynamically switching victim line. Furthermore, this paper shows the effect of inductance on delay and qualitatively optimizes its value to obtain minimum delay.

The interwire parasitics are the primary sources of crosstalk or coupled noise that may lead to critical delays/logic malfunctions. This paper is based on simulating a pair of distributed resistance inductance capacitance (RLC) interconnects coupled capacitively and inductively for measurements of crosstalk noise/delay. The combined effects of driver sizing and interwire parasitics on peak overshoot noise/delay are observed through simulation program with integrated circuit emphasis (SPICE) simulations for different switching patterns. Furthermore, the analysis of inductive effect on propagation delay as a function of coupling capacitance is carried out and the optimization of delay is worked out qualitatively. The simulations are carried out at 0.13 μm, 1.5 V technology node.

This paper observes the contradictory effects of coupling parasitics on wire propagation delay; however, the effect on peak noise is of a different kind. Further, this paper shows that the driver size exhibits opposite kind of behavior on propagation delay than peak over shoot noise. It is observed that the delay is affected in presence of inductance; thus, the optimization of delay is carried out.

The effects of driver sizing and interwire parasitics are analyzed through simulations. The optimum value of coupling capacitance for delay is found qualitatively. These findings are important for designing very large scale integration (VLSI) interconnects.

The purpose of the present study was to investigate the effect of camel milk protein hydrolysates (CMPHs) on physico-chemical, sensory, colour profile and textural quality attributes of chevon patties.

Camel milk proteins were hydrolyzed with three different proteolytic enzymes, viz., alcalase (CMPH-A), α-chymotrypsin (CMPH-C) and papain (CMPH-P), and dried to powder form before further utilization. Four treatments were prepared with incorporation of CMPH, viz., CMPH 0 per cent (C), CMPH-A 0.09 per cent (T₁), CMPH-C 0.06 per cent (T₂) and CMPH-P 0.09 per cent (T₃), in the product formulation. The developed goat meat patties were evaluated for physico-chemical (pH; emulsion stability, ES; cooking yield, CY; water activity, a_w), instrumental colour and texture profile and sensory attributes.

The pH, moisture, fat and ES values of goat meat emulsions were comparable amongst treatments as well as with the control; however, treated emulsions had higher ES and moisture content. The pH and moisture per cent of cooked chevon patties varied significantly, whereas other physico-chemical (CY, a_w, per cent protein, per cent fat, per cent ash and per cent dietary fibre) as well as dimensional parameters (per cent gain in height and decrease in diameter) were comparable amongst treatments and the control. Hardness, springiness, stringiness, cohesiveness, gumminess and resilience of chevon patties decreased significantly (p < 0.05) with the incorporation of CMPH than that of the control; however, the values were comparable among all the treated products. Protein hydrolysate in chevon patties resulted in significant increase in redness (a*) values, whereas all other parameters (L*, b* and hue) decreased significantly as compared to that of the control. The colour and appearance, texture, juiciness overall acceptability scores were comparable in all the treated products and were significantly (p < 0.05) higher than the control. The flavour scores of C, T₁ and T₃ were comparable but significantly lower than that of T₂. The overall acceptability scores of T₁ and T₂ were also comparable and significantly higher than C and T₃; however, the highest score was recorded for T₂.

Results concluded that chevon patties with acceptable sensory attributes and improved CY and textural attributes can be successfully developed with the incorporation of CMPH.

The protein hydrolysates of different food proteins could be explored in a same pattern to find out their implication in food matrices.

The purpose of this paper is to investigate the effect of inclined magnetic field, variable viscosity and Cattaneo–Christov heat and mass flux theories on the steady MHD free convective boundary layer flow of viscous, incompressible and electrically conducting water-driven silver and titanium-oxide nanofluids over a vertical stretching sheet.

The boundary layer equations of momentum, energy and nanoparticle concentration are partial differential equations in nature, which are reduced to nonlinear ordinary differential equations by means of similarity transformations. The resulting nonlinear equations are solved analytically by means of optimal homotopy analysis method.

Assessments with numerical results are performed and are found to be in an excellent agreement. Numerical results of the skin friction factor, the local Nusselt number and the local Sherwood number are obtained through tables. The effects of various physical parameters on the velocity, temperature and nanoparticles fraction are incorporated through graphs. The study analyzes the efficiency of heat transfer of nanofluids in cooling plants and rubber sheets.

No research works have been conducted to evaluate the effects of various physical phenomena on the copper and titanium nanofluids flow.

This study aims to present insights on the relationship between perceived software process improvement (PSPI) and information technology (IT)-enabled knowledge management (KM). Moreover, the study provides an understanding of the mediating effect of critical success factors (CSFs) for effective IT-enabled KM on the previously mentioned relationship.

The respondents in the study involved employees in the software engineering (SE) organizations in national capital region in India. The structured equation modeling technique carried out through IBM.SPSS.Amos.v21-EQUiNOX was used to develop and evaluate the proposed framework. The proposed hypothesis testing has been carried out by path analysis using SPSS process macro.

The findings of the empirical study reveal that a significant relationship exists between the variables under investigation. Moreover, it was observed that CSFs act as a mediator between PSPI and IT-enabled KM. The identified factors are associated with various aspects as managerial, infrastructure, financial, systems and processes for IT-enabled KM. IT acts as a moderator between KM and PSPI and facilitate the various phases of KM as knowledge creation, storage and retrieval, sharing and application of knowledge.

The present study introduces a framework for identifying and applying the CSFs that influence the KM initiatives for PSPI in an SE organization. The practitioners can use the CSFs for assessing the performance (strengths and weaknesses) in process of software development and KM practices. Researchers can use the resultant framework proposed in the empirical study for PSPI, IT-enabled KM, and in academia, the framework supports to organize the study of IT-enabled KM for PSPI.

The general comprehension of the relationship between IT-enabled KM and PSPI for Indian SE organizations is scarce in the literature. Following, the analysis expands the earlier research by exploring the mediating role of the CSFs and the moderating effect of IT for KM and PSPI relationship.

The purpose of this study was to develop functional emu meat nuggets incorporated with finger millet flour (FMF) with high fibre content and improved oxidative stability.

FMF was incorporated at 4, 6 and 8 per cent levels with replacement of emu meat in nuggets formulation and on the basis of various physico-chemical, instrumental colour and sensory parameters, 6 per cent FMF was selected as optimum. The functional emu meat nuggets incorporated with optimum level of FMF as well as control were aerobically packaged in low density polyethylene (LDPE) bags and stored for 21 days at refrigeration (4 ± 1°C) and evaluated for oxidative stability, microbiological quality and sensory attributes at regular interval of 7 days.

The fat content showed significant (p < 0.05) decrease, whereas the crude fibre content increased significantly (p < 0.05) with the increasing levels of incorporation. The sensory scores for all the attributes in 6 per cent FMF-incorporated product were higher than control. During entire storage studies, the thiobarbituric acid reactive substances (TBARS), free fatty acid and peroxide value followed an increasing trend for control as well as treatment product; however, treatment showed a significantly (p < 0.05) lower value than control throughout the storage period. Standard plate count increased significantly (p < 0.05) for control and treatment product, but the counts were lower than the prescribed limits even on 21st day of storage.

The developed products will have functional value by increasing the calcium and dietary fibre content by utilizing the minor cereals. This will be highly beneficial to both the agriculture and meat industry.

The research findings demonstrated the use of FMF in the development of calcium- and fibre-enriched emu meat nuggets with improved oxidative stability.

The demand of cement in India is expected to increase rapidly as the government has been giving immense boost to various housing facilities, infrastructure projects, road networks and railway corridors. One of the ways to meet this rise in the demand of cement is to increase the capacity utilization of the existing cement plants by improving their availability. The availability of a cement plant can be improved by avoiding failures and reducing maintenance time through reliability, availability and maintainability (RAM) analysis of its subsystems. The paper aims to discuss this issue.

The data related to time between failure (TBF) and time to repair (TTR) of all the critical subsystems of a cement plant were collected over a period of two years for carrying out RAM analysis. Trend test and serial correlation test were performed on TBF and TTR data to verify whether these data are independent and identically distributed or not. Afterwards, the authors use EasyFit 5.6 professional software to find best-fit distribution of TBF and TTR data and their parameters. The effectiveness of a preventive maintenance policy was evaluated by simulating the real and proposed systems.

The results of the analysis show that the raw mill and the coal mill are critical subsystems of a cement plant from a reliability point of view, whereas the kiln is a critical subsystem from an availability point of view. The analysis shows that the repair time of the cement mill should be reduced for improving the availability of the cement plant. The RAM analysis showed that the capacity of the case study company is 17 percent underutilized due to maintenance-related problems and 15 percent underutilized because of management-related problems.

The study exhibits the usage of RAM analysis in deciding preventive maintenance programs of several cement plant subsystems. Thus, it would serve as a reference for reliability and maintenance managers in deciding maintenance strategies of cement plants as well as in improving their capacity utilization.

The study exhibits the usage of RAM analysis in deciding preventive maintenance programs of several cement plant subsystems. Even more, using a simulation study, the authors show that preventive maintenance of the cement plant beyond a certain level can be disadvantageous as it leads to an increase in downtime and decrease in availability.