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To solve problems of low intelligence and poor robustness of traditional navigation systems, the purpose of this paper is to propose a brain-inspired localization method of the unmanned aerial vehicle (UAV).

First, the yaw angle of the UAV is obtained by modeling head direction cells with one-dimension continuous attractor neural network (1 D-CANN) and then inputs into 3D grid cells. After that, the motion information of the UAV is encoded as the firing of 3 D grid cells using 3 D-CANN. Finally, the current position of the UAV can be decoded from the neuron firing through the period-adic method.

Simulation results suggest that continuous yaw and position information can be generated from the conjunctive model of head direction cells and grid cells.

The proposed period-adic cell decoding method can provide a UAV with the 3 D position, which is more intelligent and robust than traditional navigation methods.

With respect to severe working conditions such as heavy load and impact, this paper aims to investigate the friction reduction and anti-wear performance of kaolin and molybdenum dialkyl dithiophosphate (MoDDP) composite lubricant additives to improve the lubrication effect of a single additive.

A four-ball friction test was carried out to determine the optimal concentration of kaolin and organic molybdenum additives and the tribological properties of the kaolin/MoDDP composite lubricant additives. A ring block test of composite lubricant additives was designed to investigate its lubrication performance under the severe working conditions of low speed, heavy load and impact.

The results showed that the optimal addition mass fractions of kaolin and MoDDP were 4.0 and 1.5 Wt.%, respectively, when kaolin and MoDDP were used as single lubricant additives. Compared with the single additive, the 4.0 Wt.% kaolin/1.5 Wt.% MoDDP composite lubricant additive showed excellent friction reduction and anti-wear effects under heavy load and impact conditions. Physicochemical analysis of the wear surface revealed that the lamellar kaolin additive and MoDDP had excellent synergistic effects, and the friction process promoted the generation of lubricant films containing a chemically reactive layer of MoS₂, MoO₂, FeS₂ and Fe₂O₃ and a physically adsorbent layer containing SiO₂ and Al₂O₃, which play important roles in anti-wear and friction reduction.

The excellent friction reduction and anti-wear effects of lamellar silicate minerals and the excellent antioxidant properties and good synergistic effects of molybdenum were comprehensively used to develop the composite additives with great lubricating properties.

Assistive technology (AT) is a tool to help people gain, maintain, or regain independence. AT funding options in the United States are varied. One fairly unique option is last-resort state funding, which is available in just a few states. In this case study, we explore the kinds of AT that were purchased from a state AT fund over a five-year period and for whom the AT was purchased. The case study followed a three-phase community-based participatory research process that included initial interviews with key stakeholders, compiling the data into a usable form, and follow-up interviews with key stakeholders to seek their analysis and opinions related to the data. Overall, patterns in the results were generally expected, or at least didn’t cause alarm. The data suggest that AT providers are becoming more proficient at finding ways to provide more devices and services to their clients, they are likely becoming increasingly effective at providing services to their clients without having to purchase them, they are successful in finding funding for the less expensive devices or are reusing devices that have already been purchased, and that community outreach programs are successful in increasing fund usage by ethnic minority populations. General implications of these findings are presented with the goal of improving functional outcomes for AT users.

This study aims to analyze the productivity patterns of authors in Nigeria using publications indexed in Medline from 2008 to 2012 based on Lotka’s Law. Lotka’s Law of scientific productivity provides a platform for studying inequality in authors’ productivity patterns in a given field and over a specified period.

This study covers all the journal articles on HIV/AIDS pandemic in Nigeria over a period of five years (2008-2012) in Medline, of which 512 articles were reported to have been published during this period. In this paper, 306 articles that had HIV/AIDS in the title, published in 20 journals, and articles that had HIV/AIDS as author keywords were analyzed. Because no local database that indexed biomedical literature from Nigeria was available, Medline was used, which is not only a robust and flexible database that includes articles from Nigeria but is also the largest medical database that indexes over six-and-a-half million articles from 3,400 biomedical journals.

While HIV/AIDS can be considered a global pandemic, Nigeria has the second highest number of new infections reported each year, and an estimated 3.7 per cent of the population is living with the dreaded disease. This study presents a general picture of the distribution of papers as single-author papers, multiple-author papers and the measures of co-authorship. The findings of the study reveal that in the productivity distribution for authors on the subject of HIV/AIDS, only co-authors and non-collaborative authors’ categories fit in the Lotka’s Law, whereas all-authors and first-author categories differ from the distribution of Lotka’s inverse square law.

The empirical evidence used in this paper was based on only articles of HIV/AIDS pandemic in Nigeria that had HIV/AIDS the title. Therefore, the findings of this study might not be the generalized to other biomedical research studies.

The originality of this paper lies in the fact that the productivity pattern of each of the different author categories on the subject of HIV/AIDS is a first of its kind in the Nigerian context.

Social media is widely regarded as a strategic resource to improve firm performance. However, there are mixed findings on how businesses can use social media for better performance. This study aims to propose and test a mechanism through which social media can influence firm performance.

A survey approach was used to collect data from 262 small businesses in South Africa. The data were analysed using structural equation modelling (SEM) to assess the hypothesised relationships.

The findings support the significant role of social media in fostering firm performance. It is observed that the use of social media influences firm performance through three key customer-centric constructs: the strength of customer–firm relationships, customer orientation and customer co-creation. Additionally, the relationship between the strength of customer–firm relationships and firm performance is moderated by customer co-creation.

The study provides new insights into the mechanism through which social media fosters firm performance. Due to a lack of universality in establishing the direct effect of social media use on firm performance, providing evidence of an indirect path becomes vital for advancing knowledge on social media use in business. As such, this study contributes to the literature on social media and entrepreneurship by demonstrating a novel mechanism through which social media influences firm performance.

This research aims to predict private club members’ intentions to switch service providers based on the benefit exchange theory through a structural model with a second-order factor.

This study uses a qualitative procedure to develop a functional, social and psychological model based on the benefit exchange and switching intention literatures. A further quantitative analysis surveyed a sample of 366 private club members and assessed the usefulness of this model.

The results of the confirmatory factor analysis and structural equation modeling indicate that social benefits have a stronger impact on switching intention than loss of functional benefits under the context of a high level of interaction between members and between members and service providers. In addition, they confirm the moderating effects of psychological benefits on the relationship between functional benefits and switching intention.

The findings indicate that members are unlikely to switch if there are positive word of mouth and interpersonal interactions between members and the club (social benefits). Even if they are disappointed with the functional benefits of the club’s products or services, they may still choose to stay with it owing to psychological benefits affecting their decision to switch. The findings offer managerial insights into utilizing relationship marketing activities to strengthen interpersonal relationships, word of mouth, trust, commitment and emotional factors to retain members.

This research confirms that the benefit exchange theory can explain members’ intentions to switch from their current clubs and provides valuable recommendations to managers on retaining their clubs’ members. Because the switching intentions of club members have not previously been adequately studied, this study fills an important gap in the literature.

Epoxy acrylate which is commercially utilized for UV curable coatings although has excellent adhesion, flexibility, hardness and chemical resistance, they lack in antimicrobial properties. Citric acid (CA) is economical as well as a bio-based compound which possess an antimicrobial activity. So, the purpose of this research investigation is the preparation of CA-based oligomer which can be further incorporated with epoxy acrylate and tri (propylene glycol) Diacrylate (TPGDA) to form uv curable coating and the study of its antimicrobial property.

A UV-curable unsaturated oligomer (CUV) was synthesized from CA and glycidyl methacrylate (GMA). The chemical structure of CUV was confirmed by FTIR, ¹H NMR, GPC, hydroxyl value, acid value and iodine value. Further, CUV was assimilated as an antimicrobial as well as crosslinking agent to copolymerize with epoxy acrylate oligomer and a series of UV-cured antimicrobial coatings were concocted by employing UV-curing machine. The consequence of varying the fraction of CUV on the mechanical, chemical, thermal and antimicrobial properties of UV-cured wood coatings was explored.

Results exhibited good mechanical, chemical and thermal properties. In addition, it was perceived that the zone of inhibition against S. aureus got enlarged with increasing content of CUV in the coating formulation.

The synthesized bio-based CUV reveals an extensive potential to ameliorate the antimicrobial properties of UV-curable coatings.

The purpose of this paper is to aim for the development and analysis of green manufacturing (GM)-based framework on the identified critical success factors (CSFs) and performance measures (PMs) in the context of the Indian cement industry.

The research follows survey method for data collection. For framework development, it uses factor analysis on the identified CSFs and regression along with the appropriate measures for checking statistical consistency and validity.

This is the first research towards GM framework for the Indian cement industry. Till date, no framework is available which could guide researchers and practitioners of this environment unfriendly industry. Study exposes lack of connectivity between CSFs and PMs for a GM framework and highlights weaknesses of cement industry in this regard. It offers a generalised GM framework linking PMs with top management, human resource management, organisational culture, green practices, process management and supply chain management.

The framework is expected to help both researchers and practitioners from cement, construction and other industries who are serious towards GM implementation and are looking for appropriate mechanism. This framework if implemented properly will result in enhanced productivity.

This work is one of the few and pioneering efforts to investigate GM linking CSFs and PMs in Indian manufacturing sectors and the first in cement industry. Not many studies are available in the context of cement industry, which is the lifeblood of infrastructure and construction sectors. The importance of the work increases as it is conducted in the Indian context, which is undeniably an important economy of the world.