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A new type of engine is proposed. The principle of the operation of this engine is as follows. The alternating electric current of high frequency flows from the condenser over the vertical conductor of the cross and branches at its centre in three directions. The vertical current generates a magnetic field. The horizontal currents flow in counter‐directions; therefore their magnetic fields are mutually cancelled, but the side branches of the cross are subjected to the operation of the Ampere force (F) from the magnetic field of the vertical conductor. This force moves the engine forward.

This paper aims to explore the fluid flow in the stereolithography process during the recoating step. The understanding of the flow dynamics can be used as an input for an active control of the resin surface height map. The recoating over a rectangular cavity has been considered to investigate the influence of the cavity depth on the resin surface height map.

Two-dimensional numerical simulations have been used to obtain the flow characteristics as function of the cavity depth. An experimental setup, which mimics the recoating process in the stereolithography process, was used to verify the results of simulations and to test the suitability of the 2D model. The surface height profile along the centreline was measured by a confocal chromatic distance sensor and compared to the 2D numerical results.

By means of computational fluid dynamics (CFD) simulation, the flow in the cavity and the free-surface behaviour of the resin was explained for different cavity depths and confirmed by experiments.

The study is focused only on the cavity depth variation to show feasibility and suitability of the presented CFD model and the proposed analytical expression to estimate the layer thickness.

The proposed approach can serve as a tool for designing the closed-loop control for the recoating system in the next generation of stereolithography equipment.

In the present work, the fluid flow behaviour, a source of significant imperfection in the recoating process, has been investigated during the recoating step over a rectangular cavity.

Adopting a dual processing cognitive perspective, this study explores the decision-making processes past the start-up stage that small entrepreneurial businesses employ to grow. The author examines how entrepreneurs evaluate and make decisions on growth opportunities in their business environment. The author uses cognitive style as a theoretical lens to capture differences in information processing, combining interviews and psychometric questionnaires to analyse cognitive styles. The longitudinal mixed methods approach illustrates the richness of the entrepreneur’s decision-making process, which the author tracks over a two-year period. The author determines how intuitive and analytical cognitive styles are used by entrepreneurs and the contribution these styles make to decision-making. The findings show that the two cognitive styles are versatile as entrepreneurs adjust and adapt their cognitive style over time, in keeping with the situational factors of their business environment. The author also finds marked differences between novice and mature entrepreneurs and that experienced entrepreneurs exhibited greater levels of cognitive versatility, which was directly linked to their prior experience. The study has significant implications for future research, which should consider the question how an entrepreneur’s cognitive style is dependent on the business context and their prior experience.

This chapter addresses one aspect of the broad issue of the psychological foundations of the dimensions of multidimensional scaling (MDS) solutions. Using empirical data from three independent studies, it is shown that the dimensionality of MDS solutions is negatively related to individual differences in the level of cognitive differentiation and integrative complexity of individuals and positively related to the individual's ability to discriminate within dimensions. MDS dimensionality is also shown to be affected by a variety of task-related variables such as perceived task difficulty, consistency in providing similarity judgments, confidence, familiarity, and importance attached to the stimuli. The chapter concludes by raising the issue of whether MDS can be validly used to describe complex cognitive processes.

This paper focuses on individuals' improvisation in organizations. The extant literature in this area examines improvisation as either a predictor or an outcome variable. However, there is still considerable confusion about the essence of improvisation and its individual-level determinants. To address these deficiencies, we discuss the differences between improvisation, creativity, and intuition, integrating insights and theories from those fields. Then, we propose a comprehensive model describing a process that includes contextual and individual level variables, which leads to improvisation. Finally, we discuss the theoretical and practical implications of our model and suggest avenues for future research.

The energy efficiency policy is a priority component of the overall economic policy of different countries striving to ensure the competitiveness and sustainability of national economic development. The improvement of energy efficiency represents an important economic task for the post-Soviet countries, characterized by excessive energy intensity of the economy, and the solution of this task requires proper information and analytical support: a system for accounting and analyzing energy consumption indicators. The present research is aimed at developing the tools to support decision-making in the sphere of evaluation and estimation of performance of the State energy efficiency policy of territories and testing these tools on the example of Russian regions. The study has been carried out using the methods of statistics, economic, mathematical and econometric modeling, structural, dynamic and comparative analyses. The following tools have been proposed: the method for differentiated accounting of various factors’ influence on the dynamics of energy consumption in the regions and for estimating the index of technological efficiency of electricity consumption; the method for the empirical classification of territories by types of their energy and economic development. We’ve revealed the general trend and typological features in the dynamics of electricity consumption efficiency indicators in the constituent entities of the Russian Federation and carried out the decomposition factor and comparative analysis of energy consumption patterns of the Volgograd region over 2005–2014 on the basis of the proposed tools.

While deficits for students with learning disabilities (LD) are prevalent in almost all aspects of mathematics, difficulty in the application and understanding of problem-solving tasks are much more challenging to remediate than computational and procedural skills. Given the complexities involved in authentic problem-solving activities emphasized in current mathematics standards and the inherent challenges presented to students with LD, the importance of using strategies and techniques guided by evidence-based practices is paramount. Yet, ineffective instructional strategies for problem solving are still widespread in both mathematics curricula and available teacher resources. In this chapter, we provide a description of a commonly used ineffective problem-solving strategy (i.e., the keyword strategy), an overview of the keyword research, and an explanation for its ineffectiveness. We conclude with a description of three evidenced-based problem-solving approaches and practices that significantly improve the mathematical performance of students with LD.

The purpose of this paper is to identify the role of spatial intelligence in predicting the web information searching behavior and performance of high school students.

The population of this study consisted of all female students who were studying in the eighth and ninth grades of Shiraz University School. The students searched an educational website by using keywords to find some answers to two tasks (one simple task and one complex task).

The findings of this study revealed that among the five components of spatial intelligence, the three components of spatial orientation, perceptual speed and flexibility of closure could better predict the web searching behavior and performance of the students. To elaborate, spatial orientation could predict the query length and the search time; perceptual speed was helpful in predicting the reformulation of the question, the number of results pages observed, the number of links viewed, and success; flexibility of closure also predicted the success in the search.

The results of this study can help researchers and others understand the searching behavior and performance of children and the cognitive factors which affect them. The results can also help teachers and school librarians to teach students the necessary skills and design interactive systems that take into account adolescents’ different cognitive approaches. While other studies have focused on adults’ and university students’ behavior, this study examined the adolescents’ behavior. Furthermore, although the previous studies have attempted to investigate just one dimension of the searching process, i.e., either behavior or performance, this study simultaneously focused on both dimensions and examined both searching behavior and performance through keyword searching strategy.

This study aims to investigate the differences in spatial ability between students with a math learning disability and their normal peers.

To investigate these differences two groups, (60 students with a math learning disability) and (60 normal students) from fifth grade with a mean age (10.6 years) were administered with spatial ability test along with an IQ test. Students with a math learning disability were chosen using measures of the following: math learning disability questionnaire developed from learning disability evaluation scale – renormed second edition (LDES-R²) (McCarney and Arthaud, 2007) and the Quick Neurological Screening Test (Mutti et al., 2012), in addition to their marks in formal math tests in school.

Comparison between the two groups in four aspects of spatial ability resulted in obvious differences in each aspect of spatial ability (spatial relations, mental rotation, spatial visualization and spatial orientation); these differences were clear, especially in mental rotation and spatial visualization.

This paper contributes to gain more insights into the characteristics of pupils with a math learning disability, the nature of spatial abilities and its effect on a math learning disability. Moreover, the results suggest spatial ability to be an important diagnose factor to distinguish and identify students with a math learning disability, and that spatial ability is strongly relevant to math achievement. The results have significant implications for success in the science, technology, engineering and mathematics domain.