Search results

The study aims to predict a low-velocity impact on a plate reinforced with carbon nanotubes (CNTs) using machine learning models.

The first-order shear deformation plate theory (FSDT) is used to express the plate displacements filed. The Hertz nonlinear contact law is used to predict the contact between impactor and plate. Using the energy method and Hamilton’s principle, the motion equations are extracted. The six main parameters considered as inputs to machine learning models are CNTs percentage, impactor radius, plate thickness, plate length and width, CNTs distribution profile and impactor initial velocity. These input parameters are used to predict two impact targets including contact force and contact time.

As the values of the targets are continuous, the machine learning task is considered a regression problem. Therefore, this study uses different regression models to predict the targets. These regression models include linear regression, stochastic gradient descent regressor, Bayesian regression, partial least squares regression, Gaussian process regression, multilayer perceptron regressor, support vector regression and decision tree regression. To validate the effectiveness of the regression models, experiments are designed based on different evaluation metrics. The results of the experiments demonstrate that the machine learning models achieve promising performance in predicting the contact force and contact time based on the input parameters.

Due to the volume of high numerical calculations of impact mechanics to reach the response, the targets of the impact problem are predicted using a variety of machine learning methods.

The uncertainty of consumers' perceived value makes online education enterprises face great challenge in developing the pricing strategy. So the purpose of this paper is to research the pricing strategies of online education products by considering knowledge consumers' characteristics.

Considering consumer matching degree and price comparison, this study establishes the utility functions of consumers in normal sales period and discount selling period. On this basis, the research builds pricing models of the online education enterprise under the strategy of price undertaking and intertemporal pricing strategy. It further discusses the impact of consumer matching degree, consumer price sensitivity and different types of consumers on the product price and profit of online education enterprises, and reveals the optimal pricing strategy of the enterprise.

Consumer matching degree and price sensitivity coefficient have positive effects on product price and enterprise profit, but they have different effects on product demand; there are differences in the perceived value of the three types of consumers, and matching consumers are the optimal consumer group; the intertemporal pricing strategy is better than the strategy of price undertaking only when the price sensitivity coefficient is greater than a critical value.

This study enriches the literature on the pricing model of online education products and owns a practical significance to guide the online enterprise to make marketing strategies to increase profit.

This study aims to investigate the essential components needed to develop a practical mobile application for providing library services to its users.

The study was conducted in a descriptive-survey format. The statistical population constituted the libraries worldwide using mobile applications to provide library services to the users of academic and public libraries. The data were collected through the content-analysis method, World Wide Web and checklists.

It was found that services such as search, ask a librarian, database, renew, circulation and library hours were frequently used at academic libraries, while the services of search, search through barcode scanners and database were mostly common at public libraries. According to the users of academic and public libraries, circulation and renew, search, ask a librarian and library hours were considered as the most essential services to be included in library mobile applications.

Most libraries usually use mobile apps subjectively. Thus, it is important to identify the most important components of their usage and present them in a suitable pattern. The findings of this study identified the most important components in the design and development of mobile apps and proposed the right model for their integration into libraries.

The practical mobile application proposed here for library services is applicable to all types of libraries and provides an appropriate pattern for mobile application designers.

Constrained clustering is an important recent development in clustering literature. The goal of an algorithm in constrained clustering research is to improve the quality of clustering by making use of background knowledge. The purpose of this paper is to suggest a new perspective for constrained clustering, by finding an effective transformation of data into target space on the reference of background knowledge given in the form of pairwise must- and cannot-link constraints.

Most of existing methods in constrained clustering are limited to learn a distance metric or kernel matrix from the background knowledge while looking for transformation of data in target space. Unlike previous efforts, the author presents a non-linear method for constraint clustering, whose basic idea is to use different non-linear functions for each dimension in target space.

The outcome of the paper is a novel non-linear method for constrained clustering which uses different non-linear functions for each dimension in target space. The proposed method for a particular case is formulated and explained for quadratic functions. To reduce the number of optimization parameters, the proposed method is modified to relax the quadratic function and approximate it by a factorized version that is easier to solve. Experimental results on synthetic and real-world data demonstrate the efficacy of the proposed method.

This study proposes a new direction to the problem of constrained clustering by learning a non-linear transformation of data into target space without using kernel functions. This work will assist researchers to start development of new methods based on the proposed framework which will potentially provide them with new research topics.

The purpose of this paper is to explore the period of uncertainty created by the referendum. The focus is the UK real effective exchange rate (REER). The authors set out to measure the additional impact of the uncertainty surrounding the referendum. The authors distinguish this from the longer trend value of Sterling.

The study applies a reduced form exchange rate model, first introduced by Edwards (1994), and makes use of Bank of England daily data for the period November 2015–July 2016.

The results indicate a sharp depreciation of Sterling with reference to its long-term trend. The authors set out some of the possible context which may account for fluctuations during the referendum campaigning period. This can be distinguished from other longer-term factors likely to be previously responsible for trend depreciation, and also from the further sharp depreciation effects triggered by the referendum outcome. The principal finding is that during the week of the referendum, up to the declaration of the result, exchange rate depreciation deviated from the long-run trend by approximately 3.5 per cent, but the actual immediate effect on the exchange rate was an 8 per cent depreciation. Over the period from the announcement of the referendum, the exchange rate fluctuated markedly around its trend and one can also identify a larger effect based on the “wrong-footing” of markets at the point when the outcome was announced.

The research has important implications, as one might further infer that this marks a step change in attitudes to Sterling as Brexit became a real issue rather than a notional concern. One can thus consider the exchange rate as both symptom of and indicator for determinations of the underlying economic strength or weakness of the economy. In essence, it has acted as a litmus test.

The research has important practical implications in understanding the dynamics of the exchange rate market and the role of uncertainty in its dynamics.

The study has important social implications as the changes to exchange rates are a perennial cause for concern. Exchange rates sit as one among many problems for the contemporary UK economy. Brexit has resulted in a significant subsequent depreciation of Sterling. Inter alia, though the immediate effect of Brexit on growth was muted due to unexpected sustained consumer spending, throughout the latter half of 2016 and the first two quarters of 2017, business investment slowed, the rate of deficit reduction slowed (but without any concomitant meaningfully rise in government investment in infrastructure, etc.) and both main measures of inflation began to rise.

The study contributes to the existing body of knowledge by exploring the period of uncertainty created by the referendum and its implications for the UK REER. The study differentiates and reflects on the weakness of Sterling due to the weak external position of UK’s economy and the further role played by the uncertainty surrounding Brexit. In this sense, it important contribution to theory as well as practice.

The purpose of this study is to explore the current state of knowledge of sustainable entrepreneurship (SE) and to gain more insights from the articles originated from the emerging economies. This paper also sets an agenda for future research in this knowledge domain.

The authors perform a systematic literature review by analyzing the primary studies related to SE originating from emerging economies from Asia, Africa and the Middle East. This review scrutinizes a total number of 45 studies to explore the current state of research in this knowledge domain from such economies.

Overall, this review finds that SE research is still at the nascent stage, especially in the context of emerging economies. The authors elicit a few sub-themes, within the SE research, such as individual-level factors, organizational-level factors, institutional-level factors and cultural and social factors.

The authors present a few limitations of this study. Firstly, this study uses articles from the Scopus and Web of Science only. Secondly, this systematic review is limited to the articles originated from emerging economies of Asia, Africa and the Middle East. Thirdly, this review gives overall picture of the SE research in emerging economies and the same in other economies is not in the scope of this study.

The findings of this study will be helpful to the researchers to locate avenues for future course of research in SE field. This study helps the policymakers and educational institutions of emerging economies understand and ingrain sustainability element in entrepreneurship, and thereby helps them to fulfill sustainable economy and sustainable development goals.

To the best of the authors’ knowledge, this study is the first of its kind in the field of SE in emerging economies. This review gives more insights on the state of SE in the emerging economies, as these economies can significantly contribute to the realization of Sustainable Development Goals.

The purpose of this paper is to examine perfume packaging in Spain and its effects on Basque female consumers’ purchase decision. The study population was made up of females, as they represent the highest consumer in the perfume market, accounting for 67 percent of the total perfume sales (Trufragance.com). Furthermore, in the past few years the perfume industry has basically targeted females (McIntyre, 2013).

An empirical study was conducted using a questionnaire to collect primary data in order to test the hypotheses. The questionnaire was distributed to 400 randomly selected respondents, from the general female population.

The findings show a relationship between the independent variables (i.e. visual packaging design, verbal packaging design, and packaging benefits) and the dependent variable (i.e. consumer purchase decision) based on several reasons discussed thoroughly in this paper. Additionally, age, education level, marital status, monthly income, and employment category of sample subjects influence the effect of perfume packaging on purchase decisions.

The main limitation of this study is the use of simple random sampling. The research findings bear important implications for more functional, emotional, environmental, and socially responsible marketing practice where packaging is concerned.

The findings of this study contribute to the understanding of packaging as a strategic marketing tool and how it can significantly influence the female’s purchase decision. Thus, giving managers and marketers a competitive advantage in this increasingly growing market. A new concept and measurement scale is presented that can be used for identifying creative packaging design and its benefits.

This study remains one of few research works focusing on the four dimensions of packaging benefits: functional, social, emotional, and environmental. Furthermore, it attempts to fulfill the identified need for encompassing potential and generally accepted packaging elements, including both the visual and verbal elements. Therefore, the uniqueness of this study arises from its examination of both aspects simultaneously, which has been ignored in previous research.

The purpose of the article is to construct a new class of higher-order iterative techniques for solving scalar nonlinear problems.

The scheme is generalized by using the power-mean notion. By applying Neville's interpolating technique, the methods are formulated into the derivative-free approaches. Further, to enhance the computational efficiency, the developed iterative methods have been extended to the methods with memory, with the aid of the self-accelerating parameter.

It is found that the presented family is optimal in terms of Kung and Traub conjecture as it evaluates only five functions in each iteration and attains convergence order sixteen. The proposed family is examined on some practical problems by modeling into nonlinear equations, such as chemical equilibrium problems, beam positioning problems, eigenvalue problems and fractional conversion in a chemical reactor. The obtained results confirm that the developed scheme works more adequately as compared to the existing methods from the literature. Furthermore, the basins of attraction of the different methods have been included to check the convergence in the complex plane.

The presented experiments show that the developed schemes are of great benefit to implement on real-life problems.

This study empirically analyse the lived and individual experiences of internet use time among postgraduate students in a period where the line between the virtual and real is blurred. The infusion of the internet in higher education has not only facilitated the production of new knowledge but has also led to reports of internet addiction among many users during the COVID-19 pandemic and the resulting lockdowns. This study aims to evaluate the level of internet addiction among postgraduate students and the supportive information services role that librarians could provide.

In this study, 279 postgraduate students completed a quantitative survey targeted at all the postgraduate students at a university campus in South Africa. Data was collected using an adopted internet addiction test questionnaire. The data was descriptively and inferentially analysed.

As many as 61 (22.7%) are always online, with most of the respondents, 112 (41.6%) spend 10 h or more on the internet daily. Laptop computers at 44.7% emerged as the primary electronic device used by postgraduate students for accessing the internet, surpassing the prevalence of mobile phone usage. On internet addiction level, internet use time had a statistically significant relation with problematic internet use levels in respondents. These results suggest that the increased uncontrolled internet use could negatively interfere with productive academic work of postgraduate students. However, based on the inferential statistical results, it can be concluded that academic use of the internet does not contribute to increased levels of internet addiction. The study recommends that librarians should provide literacy education and resources on how to use the internet safely and responsibly, including tips on setting boundaries, managing time online and productively using online information resources.

The study assesses problematic internet use among postgraduate students and provides suggestions on supportive information services that librarians could provide in an era where many library information services provision and higher education are hinged on the internet.

Milling is a flexible creation process for the manufacturing of dies and aeronautical parts. While machining thin-walled parts, heat generation during machining essentially affects the accuracy. The workpiece temperature (WT), as well as the responses like material removal rate (MRR) and surface roughness (SR) for input parameters like cutting speed (CS), feed rate (F), depth-of-cut (DOC), step over (SO) and tool diameter (TD), becomes critical for sustaining the accuracy of the thin walls.

Response surface methodology was used to make 46 tests. To convert the multi-character problem into a single-character problem, the weightage was assessed using the entropy approach and the grey relational coefficient (GRC) was determined. To investigate the connection among input parameters and single-objective (GRC), a fuzzy mathematical modelling technique was used. The optimal performance of process parameters was estimated by grey relational entropy grade (GREG)-fuzzy and genetic algorithm (GA) optimization.

SR was found to be a significant process parameter, with CS, feed and DOC, respectively. Similarly, F, DOC and TD were found to be significant process parameters with MRR, respectively, and F, DOC, SO and TD were found to be significant process parameters with WT, respectively. GREG-fuzzy-GA found more suitable for minimizing the WT with the constraint s of SR and MRR and provide maximum desirability of 0.665. The projected and experimental values have a good agreement, with a standard error of 5.85%, and so the responses predicted by the suggested method are better optimized.

The GREG-fuzzy-GA is a new hybrid technique for analysing Inconel625 behaviour during machining in a 2.5D milling process.