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During the last few years the teaching of electrical machinery has been increasingly influenced by the unified theory proposed by Gabriel Kron. This theory has been the subject, at graduate level, of a number of special courses and it is likely that, in common with degree syllabuses, it will be introduced in Dip. Tech. courses. While it is true that a complete understanding of the theory requires elaborate mathematics, the physical basis of the theory can be usefully established when a student commences his study of electrical machines, e.g. at the ONC level.

The primary purpose of this work is to prepare the renewable source-based polyurethanes coatings which can be used to substitute petroleum-based materials. In the secondary purpose, the paper included improvement in the properties of said PU coatings using modified nano TiO₂ for industrial PU coatings.

The authors have synthesised low molecular weight polyols (monoglycerides) based on vegetable oils such as castor, linseed, coconut, mustard, sunflower and rice bran oils. These monoglycerides were successfully utilised in the preparation of polyurethane coatings. In order to improve the performance of these coatings, modified nano TiO₂ was incorporated into them. The particle size of TiO₂ was determined by transmission electron microscopy. Coatings prepared were characterised for their properties such as gloss, scratch resistance, impact resistance, flexibility, cross cut adhesion and chemical resistance. The thermal stability of coatings was also studied by thermo gravimetric analyzer.

The polyurethane coatings prepared from six monoglycerides of different oils with polymeric diphenyl methane diisocyanate showed good chemical resistance and thermal stability. Coating properties like impact resistance, flexibility and adhesion were excellent for all of the prepared samples of PU coatings. PU coatings with excellent hardness up to 5B were found with the modification of nano TiO₂ by silane coupling agent. The authors successfully prepared the renewable source-based (monoglycerides of oil) PU coatings.

Practically the authors are able to convert renewable source that is vegetable oils into polyurethane coatings which may have strong potential to be used as industrial surface coating. The properties of the PU coatings were evaluated before and after the incorporation of different concentration of surface-modified nano TiO₂ which revealed that the presence of 1 percent nano TiO₂ showed significant enhancement in coating properties.

The beauty of this work includes synthesis of polyurethanes coatings from renewable source material (monoglycerides of vegetable oils) to substitute petroleum-based materials. The incorporation of silane-modified TiO₂ nanoparticles in renewable source-based PU coatings is another originality of the work. This article is also representing comparative study of various vegetable oils on PU coatings.

The purpose of this study is to present the effectiveness and robustness of a numerical algorithm based on the block Newton method for the nonlinear kinematic hardening rules adopted in modeling ductile materials.

Elastoplastic problems can be defined as a coupled problem of the equilibrium equation for the overall structure and the yield equations for the stress state at every material point. When applying the Newton method to the coupled residual equations, the displacement field and the internal variables, which represent the plastic deformation, are updated simultaneously.

The presented numerical scheme leads to an explicit form of the hardening behavior, which includes the evolution of the equivalent plastic strain and the back stress, with the internal variables. The features of the present approach allow the displacement field and the hardening behavior to be updated straightforwardly. Thus, the scheme does not have any local iterative calculations and enables us to simultaneously decrease the residuals in the coupled boundary value problems.

A pseudo-stress for the local residual and an algebraically derived consistent tangent are applied to elastic-plastic boundary value problems with nonlinear kinematic hardening. The numerical procedure incorporating the block Newton method ensures a quadratic rate of asymptotic convergence of a computationally efficient solution scheme. The proposed algorithm provides an efficient and robust computation in the elastoplastic analysis of ductile materials. Numerical examples under elaborate loading conditions demonstrate the effectiveness and robustness of the numerical scheme implemented in the finite element analysis.

The aim of this paper is to investigate microwave Ku band absorbance, complex permittivity, and permeability of SrFe₁₂O₁₉ thick films by a simple and novel waveguide technique.

The glass frit free or fritless strontium hexaferrite thick films were formulated on alumina by screen printing technique from the powder synthesized by chemical co precipitation method for pH 11 adjusted during the reaction. The 13‐18 GHz frequency band microwave absorbance of the SrFe₁₂O₁₉ thick films by a simple waveguide method. The complex permittivity and permeability of strontium hexaferrite thick films was measured by voltage standing wave ratio technique.

SrFe₁₂O₁₉ thick films show high ∼80 percent absorbance in the whole 13‐18 GHz frequency band. The thickness dependant microwave properties of strontium hexaferrite thick films were observed. The real permittivity ε′ lies in between eight and 35 with the variation in thickness of the thick film SrFe₁₂O₁₉. The real microwave permeability μ′ of strontium hexaferrite thick films lies in the range 1.12‐6.41. The resonance type behavior was observed at frequency 14.3 GHz. The SrFe₁₂O₁₉ thick film of thickness 30 μm could be a wide band (∼5,000 MHz) absorber with absorbance ∼87 percent for the whole 13‐18 GHz frequency band.

The complex permeability of strontium hexaferrite thick films was measured by simple novel waveguide method. The high absorbance (∼87 percent) of thick film SrFe₁₂O₁₉ over a broad band ∼5,000 MHz will be useful in achieving RAM coatings required for 13‐18 GHz frequency band.

The growth of online communities and social media has led to a growing need for methods, concepts, and tools for researching online cultures. Particular attention should be paid to polarizing online discussion cultures and dynamics that increase inequality in online environments. Social media has enormous potential to create good, but in order to unlock its full potential, we also need to examine the mechanisms keeping these spaces monotonous, homogenous, and even hostile toward some groups. With this need in mind, I have developed the concept and theory of othering online discourse (OOD).

This chapter introduces and defines the concept of OOD and explains the key characteristics and different attributes of OOD in relation to other concepts that deal with disruptive and discriminatory behavior in online spaces. The attributes of OOD are demonstrated drawing on examples gathered from the Finnish Suomi24 (Finland24) forum.

The recent pandemic has witnessed increased digitalization. The supply chain disruptions have forced businesses to adopt innovative business strategies that were not prevalent in previous years. This chapter elaborates on how integrating disruptive technologies such as artificial intelligence (AI), blockchain, and the Internet of Things (IoT) into business strategies is essential for modern organizations. It emphasizes creating and capturing value through business model innovation, highlighting the significance of developing a value proposition differentiating an enterprise in the market. This involves rethinking and redesigning how organizations create customer value, leveraging these technologies to enhance efficiency, customer experience, and competitive advantage. This chapter advocates for a proactive approach to technology adoption, stressing the importance of agility, innovation, and a forward-thinking leadership mindset in capitalizing on the opportunities presented by technological advancements.

T-spline is the latest powerful modeling tool in the field of computer-aided design. It has all the merits of non-uniform rational B-spline (NURBS) whilst resolving some flaws in it. This work applies T-spline surfaces to additive manufacturing (AM). Most current AM products are based on Stereolithograph models. It is a kind of discrete polyhedron model with huge amounts of data and some inherent defects. T-spline offers a better choice for the design and manufacture of complex models.

In this paper, a direct slicing algorithm of T-spline surfaces for AM is proposed. Initially, a T-spline surface is designed in commercial software and saved as a T-spline mesh file. Then, a numerical method is used to directly calculate all the slicing points on the surface. To achieve higher manufacturing efficiency, an adaptive slicing algorithm is applied according to the geometrical properties of the T-spline surface.

Experimental results indicate that this algorithm is effective and reliable. The quality of AM can be enhanced at both the designing and slicing stages.

The T-spline and direct slicing algorithm discussed here will be a powerful supplement to current technologies in AM.

The purpose of this paper is to study thermal stability, curing kinetics and physico‐chemical properties of polyurethanes systems for application in in‐mould decoration (IMD) ink.

The thermal stability of three Polyurethane (Pu) systems A, B, C were evaluated by thermogravimetric analysis (TGA). The kinetic parameters of the curing reaction of Pu system C were calculated using non‐isothermal curing kinetics analysis, including the activation energy Ea, the reaction rate constant K(T), the reaction order n, the initial curing temperature (Ti), the peak temperature (Tp), and the finishing temperature (Tf). Additionally, physico‐chemical properties were also evaluated such as flexibility, impact resistance, pencil hardness, adhesive attraction and solvent resistance.

TGA showed that thermal decomposition temperature T5 (5 wt.% weight loss), T10 (10 wt.% weight loss) and Tend (decomposition termination temperature) of Pu system C was 344°C, 363°C, and 489°C, respectively. T5, T10, Tend increased by 77°C, 61°C, 4°C, respectively, and the char yield at 600°C increased by 25.1 wt.% comparing with Pu system B. Curing kinetics analysis showed that Ea of Pu system C was 62.29 KJ/mol, 65.98 KJ/mol and 65.95 KJ/mol by Kissinger, Flynn‐Wall‐Ozawa and Ozawa method, respectively. The order of the curing reaction (n=0.90) demonstrated that it was a complex reaction. Moreover, Pu system C exhibited good physico‐chemical properties. The results showed that Pu system C was suitable to apply into IMD ink.

The TGA analysis, curing kinetics analysis and evaluation of physico‐chemical properties provided a simple and practical solution to study suitable resins for IMD ink application.

IMD ink for heat transfer printing technology is highly efficient, relatively low cost, clean and environmentally safe. It has been widely applied into medical and pharmaceutical products, electronic devices, telecommunication equipment, computer parts, appliance panels, automotive parts, etc.

In this paper, the thermal stability and curing kinetics of Pu for IMD ink are reported for the first time. The paper gives very interesting and important information about thermal stability, curing kinetics and properties of Pu coating system for IMD ink application.

Dysphagia experienced by adults with mental health conditions and/or intellectual disabilities (IDs) has been well-reported. However, accessible and inclusive assessment measures to identify and monitor for deterioration in dysphagia are very limited. The purpose of this paper is to explore the use of video to enhance inclusion in dysphagia assessment and intervention for an inpatient setting.

This service evaluation involved adults with IDs and mental illness living in in-patient accommodation and their multidisciplinary team. Participants were invited to film and then reflect on videos and their comments were transcribed for qualitative analysis.

In total, 42 adults gave consent to film, review and discuss mealtime video-clips. Staff feedback was invited. Thematic analysis was conducted for service-user and staff comments. A global theme of “involvement” was identified from the data analysis, with sub-themes of “enhancing participation, insight and incentive”. An additional global theme “clinical benefits” resulted from staff comments. This included sub-themes of breadth of assessment, shared working and outcome measures.

Limitations included refusal of video by people with heightened anxiety but these were a minority. Most people showed enthusiasm and enhanced engagement. Practical issues were resolved regarding governance.

Video offers a dynamic record of muscle tone, coordination, mealtime experience and individual context benefiting both service-user and staff practice. It stimulates insightful discussion of outcomes and supports the inclusion of service-user perspectives. Further research is indicated to develop a greater understanding of dysphagia in this population. Inclusion of service-users in planning and managing safer mealtimes may be enhanced through the sensitive use of video.

This evaluation suggests opportunities for improving inclusive approaches for service-users using video to promote insight.

Further research is indicated to explore the nature of dysphagia in people with mental health conditions using video as a dynamic and unique resource.

The purpose of this paper is to report on the Ku band microwave characteristics of moisture laden soya seeds using overlay technique.

Ku band (13‐18 GHz) moisture dependent microwave permittivity, conductivity, penetration depth of moisture laden soybean (Glycine Max) using overlay on Ag thick film equilateral triangular patch antenna are studied. The change in the frequency response of the patch antenna due to change in moisture content of the soybean overlay has been used to obtain the various microwave properties.

The permittivities obtained are in the range expected of moisture laden soybean. As moisture content increases microwave dielectric constant, dielectric loss, and conductivity of soybean increases. Only the amplitude data have been used here.

Ku band characterization of soybean has been done using overlay technique. The thick film patch antenna is sensitive even to ∼4 percent moisture content in the overlay material. This can be used for even moisture sensing at low moisture levels. This paper is believed to be an original research report.