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The purpose of this study is to investigate the behaviour of M40 grade of self-compacting concrete (SCC) with high volume of ground granulated blast furnace slag (GGBS) (50%) and recycled concrete aggregate (RCA) content up to 100% to assess the mechanical properties of SCC. As per guidelines of IS: 383 – 2016, the RCA can be replaced up to 20% of natural coarse aggregate up to M25 grade of concrete. This study assesses the mechanical properties of SCC beyond 20% of RCA content. Based on the experimental investigations, the compressive strength of mixes decreases as the content of RCA increases. It is found that concrete mixes with 20% RCA and shows the maximum compressive strength at 56 days.

The fresh properties as per EFNARC and IS: 10262–2019 guidelines, ultrasonic pulse velocity testing, mechanical properties and microstructure analysis have been conducted to evaluate the performance of SCC with RCA for practical applications.

From the experimental investigations, it is found that up to 50% of recycled coarse aggregate can be used for structural applications.

The environmental pollution and dumping of waste on green land can be reduced by effective utilization of recycled coarse aggregate and GGBS in the production of SCC.

The purpose of this paper is to investigate the effect of the replacement of natural coarse aggregate (NCA) with different percentages of recycled coarse aggregate (RCA) on properties of low calcium fly ash (FA)-based geopolymer concrete (GPC) cured at oven temperature. Further, this paper aims to study the effect of partial replacement of FA by ground granulated blast slag (GGBS) in GPC made with both NCA and RCA cured under ambient temperature curing.

M25 grade of ordinary Portland cement (OPC) concrete was designed according to IS: 10262-2019 with 100% NCA as control concrete. Since no standard guidelines are available in the literature for GPC, the same mix proportion was adopted for the GPC by replacing the OPC with 100% FA and W/C ratio by alkalinity/binder ratio. All FA-based GPC mixes were prepared with 12 M of sodium hydroxide (NaOH) and an alkalinity ratio, i.e. sodium hydroxide to sodium silicate (NaOH:Na₂SiO₃) of 1:1.5, subjected to 90^°C temperature for 48 h of curing. The NCA were replaced with 50% and 100% RCA in both OPC and GPC mixes. Further, FA was partially replaced with 15% GGBS in GPC made with the above percentages of NCA and RCA, and they were given ambient temperature curing with the same molarity of NaOH and alkalinity ratio.

The workability, compressive strength, split tensile strength, flexural strength, water absorption, density, volume of voids and rebound hammer value of all the mixes were studied. Further, the relationship between compressive strength and other mechanical properties of GPC mixes were established and compared with the well-established relationships available for conventional concrete. From the experimental results, it is found that the compressive strength of GPC under ambient curing condition at 28 days with 100% NCA, 50% RCA and 100% RCA were, respectively, 14.8%, 12.85% and 17.76% higher than those of OPC concrete. Further, it is found that 85% FA and 15% GGBS-based GPC with RCA under ambient curing shown superior performance than OPC concrete and FA-based GPC cured under oven curing.

The scope of the present paper is limited to replace the FA by 15% GGBS. Further, only 50% and 100% RCA are used in place of natural aggregate. However, in future study, the replacement of FA by different amounts of GGBS (20%, 25%, 30% and 35%) may be tried to decide the optimum utilisation of GGBS so that the applications of GPC can be widely used in cast in situ applications, i.e. under ambient curing condition. Further, in the present study, the natural aggregate is replaced with only 50% and 100% RCA in GPC. However, further investigations may be carried out by considering different percentages between 50 and 100 with the optimum compositions of FA and GGBS to enhance the use of RCA in GPC applications. The present study is further limited to only the mechanical properties and a few other properties of GPC. For wider use of GPC under ambient curing conditions, the structural performance of GPC needs to be understood. Therefore, the structural performance of GPC subjected to different loadings under ambient curing with RCA to be investigated in future study.

The replacement percentage of natural aggregate by RCA may be further enhanced to 50% in GPC under ambient curing condition without compromising on the mechanical properties of concrete. This may be a good alternative for OPC and natural aggregate to reduce pollution and leads sustainability in the construction.

This paper aims to investigate the current status of research output published in open access (OA) journals from Brazil, Russia, India, China and South Africa (BRICS) countries from 2010 to 2019 and compare their performances in terms of OA research output.

Papers contributed by the researchers of BRICS countries were searched using an advanced search option in the Web of Science core collection database. The retrieved results were restricted to the “journal articles” published in the “English language” during the time period of 2010 to 2019. After that, the selected papers were again refined by using the “open access” section to identify the research output of BRICS countries published in OA journals.

Total 2,219,943 papers were published from BRICS countries, out of which 402,199 articles were published in OA journals and South Africa has published the highest number of research output in OA journals (31%). Although, there has been a constant increasing growth of research output published in OA journals in BRICS countries from 13,300 papers in 2010 to 82,310 articles in 2019. Engineering and Technology have published the maximum number of papers in OA journals. Researchers of BRICS countries mostly contributed their OA research output in journals published from the USA and Scientific Reports (UK) is identified as one of the leading OA journals. Additionally, among all the BRICS countries, China is found as the promising leader in terms of OA journals publications, the maximum share i.e. 71.25 per cent of total 402,199 OA journal publications have been produced by the highest number 137 (23.41%) of institutions of China and Chinese Academy of Sciences (China) is leading institution with 39,036 papers published in OA journals.

This study is limited to BRICS countries, but it offers theoretical implications for extending its scope to different countries. This study may be used for raising awareness of OA among researchers of BRICS countries and encouraging them to contribute their research work in OA journals. The findings of this study are useful and meaningful in understanding the comparative status of research across countries, disciplines, journals and institutions.

This is the first study in BRICS countries focusing on the research output published in OA journals.

The purpose of this study is to empirically investigate the mediating role of knowledge management (KM) in the linkage between organizational factors, namely, organizational culture (OGCUL) and leadership and management support (LMS) and innovation in medium- and large-scale manufacturing firms in Ethiopia.

A sample of 200 firms has been used to gather data using simple random sampling and to test the proposed hypotheses. Structural equation modeling and cross-sectional design were used to analyze the data using LISREL 8.80 SIMPLIS program software tool.

Organizational factors (i.e. OGCUL and LMS) are positively associated with KM and innovation. KM constructs, namely, knowledge sharing, knowledge conversion and knowledge storage, have a significant positive influence on innovation. Knowledge sharing mediates the relationship between organizational factors and innovation.

This study has three potential limitations: first, this study is based on a cross-sectional research design. Future research should include longitudinal design to get in-depth insights into the causal inferences. Second, only a few Ethiopian medium- and large-scale manufacturing firms were included in the sample. As a suggestion for future research, other researchers can include small-scale enterprises using large sample sizes and should examine the effects of organizational factors, KM and innovation across different industries. Finally, this study has only focused on investigating the mediating role of knowledge sharing between organizational factors and innovation. Future research should test the mediating role of the KM process and its constituents (knowledge acquisition, knowledge conversion, knowledge sharing and knowledge storage) between organizational factors and specific aspects of innovation to gain a full understanding of the critical role of KM in organizational innovation.

The findings of this study would serve as a guide for policy-makers and managers of manufacturing firms in developing countries in the formulation of policies and long-term strategies. It may also provide a better understanding of the causal relationship between organizational factors, KM and innovation, which in turn has value to directors and managers in manufacturing firms in developing countries as a reference for building a good OGCUL, serving as practical guidance for effective leadership and providing organizational or management support. Specifically, the findings would have the following practical implications: first, firms need to have a combination of KM processes (such as acquisition, storage, sharing and conversion). In practice, developing countries such as Ethiopia have based their innovation strategy on knowledge and technology acquisition through encouraging foreign direct investment. It is not in doubt that Ethiopia has been benefiting from the strategy as a lot of foreign companies have opened their subsidiaries in the country. However, in the authors’ view, more emphasis on knowledge acquisition strategy would not take a firm a long time to sustain its innovative activity because it is likely available to firms operating in the same industry, as well as it may hurt a firm’s competitive advantage. In addition, by its nature, knowledge may not be retained for future use; it may expire soon. Second, the current highly impulsive and rapid change in the business environment changes the way firms have to operate and deliver products or services. Knowledge (both tacit and explicit) is a resource that can provide a competitive advantage if used well for the intended purpose. In real practice, firms often face challenges in determining where to get knowledge from and how to value or manage it. Besides, knowledge can be obtained from three sources: knowledge can exist in individuals’ minds (skills, experience, ideas and insight); knowledge can dwell in a group, which we can call collective knowledge (a team of scientists or researchers); and knowledge can be embodied in an organization's systems, tools, procedures, policies, etc. Knowledge cannot be a valuable resource unless it is obtained and used in designing or producing a product or service. To integrate knowledge with business strategies, there should be a platform or framework that helps to manage it properly. Firm managers, policy-makers and other concerned bodies would consider the three sources of knowledge to foster innovative activities and obtain a competitive advantage. In addition, the authors recommend more emphasis be placed on firm-specific factors (such as OGCUL, leadership, management support and KM) to enhance the innovative capacity of a firm. Finally, the most critical issue to be raised while designing an innovation strategy would be employees’ willingness and passion to collaborate with others to develop new ideas, share ideas or implement policies. As knowledge resides in individuals’ minds, the knowledge holder should have a passion to share it with those working with him or her. In practice, knowledge sharing depends extremely on the passion and voluntariness of the two parts: knowledge provider and receiver. Therefore, firm managers would design a platform on how to motivate individuals to share their skills, experience and ideas with others through providing incentive packages, punishment and commitment. In this regard, the authors believe that the results would help individuals who are in the position to manage or regulate the manufacturing sector in designing innovation policies, KM policies or technology management policies and business strategies.

This study provides new empirical insight into the relationships between organizational factors (such as OGCUL and LMS), KM and innovation in a large sample of firms. To date, the empirical research on these relationships has been mainly limited to descriptive case studies (Chen and Huang, 2009; Zack et al., 2009; Donate and Guadaumillas, 2011), and there is thus a lack of empirical evidence with large samples of firms. Furthermore, there is a scarcity of studies investigating the relationship between organizational factors, KM and innovation in developing countries, especially in Ethiopia. This paper intends to fill this gap and nurture future research studies in the area.

In the design and development stage of the power converter systems, an abnormal intermittency is naturally experienced in nonautonomous system because of coupling of the interference signals. The study of identifying the possible conditions at which such an undesirable operation emerges is vital. Hence, the purpose of this paper is to explore the intermittent instabilities that evolve in the voltage-mode controlled quadratic buck converter when the sinusoidal interference signal coupled in reference voltage.

Voltage-mode controlled quadratic buck converter with the sinusoidal interference signal coupled in reference voltage manifests a symmetrical period-doubling bifurcation in intermittent periods for significant interference signal strength with the frequency near to the switching frequency or its rational multiples. The complete dynamics of the system is investigated for the various inference signal frequencies by numerical simulations.

Here, the intermittent instabilities are verified using a simple Filippov’s method with supporting evidence of Floquet multipliers (eigenvalues) movement. The analytical result obtained is found to agree well with the simulation results.

Power supplies are liable to an ambiguous complex behavior when it is seldom protected against the interference signal. The experimental study has made an attempt to explicit a detailed behavior observed in voltage-mode controlled quadratic buck converter when a sinusoidal intruding signal of different amplitude and frequency are coupled with the reference voltage. Such an analysis gives considerable focus for the power electronics engineers to meet the design requirements.

To the authors’ knowledge, all the research works on intermittent instabilities in power converters are analyzed only using conventional method of Poincare map technique which emerges to be complicated when the order of the system is higher. Alternatively, in this paper, Filippov’s technique is used for stability analysis of periodic orbit. The evolution of bifurcation point is predicted by the calculating the Floquet multipliers of monodromy matrix, and it is known to achieve the same objective as the Poincare map technique in much more straightforward way.

In this chapter, we describe the belief system of Izzat which is central among South Asian families. The idea of forced marriage is based upon the concept of Izzat or honor which is a cornerstone of family life in South Asian communities.

Rai (2006) suggests that South Asian community members are deeply affected by what others say about them. The closest English translations to Izzat and Sharam are honor and shame, respectively. Rai argues that Izzat and Sharam are mechanisms that safeguard patriarchal customs such as arranged marriage which are familiar to us from our own backgrounds as two Asian women. It is our belief that Izzat is the highest “context marker” (Pearce & Cronen, 1980) for forced marriages.

We will illustrate the concept of Izzat through two case vignettes and explicate theoretical ideas, based on Izzat to include Borzemyi-Nagy’s ideas about belief systems.

The research of Ryan Brown (2016) University of Oklahoma on “honour cultures” in the USA draws some parallels in gendered discourses about power of men over women. He suggests that high levels of murder rates as well as reluctance to address mental health issues are present in “honour cultures.” These ideas resonate with the strong influence of Izzat upon South Asian family and community systems which we have met in our practice. The development of our practice was in response to issues arising from our clinical work in these communities (Robinson, 2016).

We will explore the continuum of marriage to include forced, arranged and consensual marriage within the context of Izzat and compare with black African and African-Caribbean families.

We will also consider issues of cultural competence and expertness and how this interplays with strongly held belief systems such as Izzat. We will end with some clinical implications and pointers for practice.

This paper aims to target tracking in the marine environment is typically obtained by considering the measurement parameters like frequency, elevation and bearing. Marine environmental surveillance provides critical information and assistance for the exploitation and maintenance of marine resources.

With the use of intelligent sensor techniques like Hull-mounted and towed array sensors, convenient, precise and dependable three-dimensional (3D) underwater target tracking is introduced.

This research investigates a method to develop a reliable Unscented Kalman Filter (UKF) algorithm for enhanced underwater target tracking in a 3D scenario by using bearing, frequency and elevation measurements. In applications for underwater target tracking, uncertainty and inaccuracies are typically described by using Gaussian additive noise.

The proposed UKF algorithm is tested and analyzed using 100 Monte Carlo simulations with the Gaussian generated noise.

Nowadays advancement in acoustic technology can be explored with marine assets. The purpose of the paper is pervasive computing underwater target tracking has aroused military and civilian interest as a key component of ocean exploration. While many pervasive techniques are currently found in the literature, there is little published research on the effectiveness of these paradigms in the target tracking context.

The unscented Kalman filter (UKF) provides good results for bearing and elevation angles only tracking. Detailed methodology and mathematical modeling are carried out and used to analyze the performance of the filter based on the Monte Carlo simulation.

Due to the intricacy of maritime surroundings, tracking underwater targets using acoustic signals, without knowing the range parameter is difficult. The intention is to find out the solution in terms of standard deviation in a three-dimensional (3D) space.

A new method is found for the acceptance criteria for range, course, speed and pitch based on the standard deviation for bearing and elevation 3D target tracking using the unscented Kalman filter covariance matrix. In the Monte Carlo simulation, several scenarios are used and the results are shown.

This chapter examines the marketplace activities of subsistence customers in South India. It presents a picture of the day-to-day behaviors and interactions of subsistence customers in terms of the products they purchase and their interactions with sellers and outlets. The method involved observations and in-depth interviews of a variety of buyers and sellers over several years in urban and rural South India. Needs, products, and market interactions, as well as typical budgets in subsistence contexts are described. These descriptions are used to derive broader characteristics of product and market interactions in terms of uncertainty, complexity, and lack of control; one-on-one interactions; transactional fluidity; and make or buy decisions.

Marine exploration is becoming an important element of pervasive computing underwater target tracking. Many pervasive techniques are found in current literature, but only scant research has been conducted on their effectiveness in target tracking.

This research paper, introduces a Shifted Rayleigh Filter (SHRF) for three-dimensional (3 D) underwater target tracking. A comparison is drawn between the SHRF and previously proven method Unscented Kalman Filter (UKF).

SHRF is especially suitable for long-range scenarios to track a target with less solution convergence compared to UKF. In this analysis, the problem of determining the target location and speed from noise corrupted measurements of bearing, elevation by a single moving target is considered. SHRF is generated and its performance is evaluated for the target motion analysis approach.

The proposed filter performs better than UKF, especially for long-range scenarios. Experimental results from Monte Carlo are provided using MATLAB and the enhancements achieved by the SHRF techniques are evident.