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This paper is concerned with the design and analysis of a bearingless motor.

The bearingless motor is obtained by a regular three-pole active magnetic bearing with an intentionally attached unbalanced mass on the rotor. It is the unbalanced mass that will generate the rotational torque for the motor function. Modeling and control of the unbalanced mass-type bearingless motor have been considered.

It is found through simulations that both functions of motor and magnetic bearing can indeed be achieved in this system.

This novel bearingless motor requires no additional windings and permanent magnets. Thus, it can greatly reduce the cost and design of the bearingless motor.

This study aims to investigate the relationship between dietary polyamine levels, metabolic risk parameters and anthropometric measurements in postmenopausal women.

This cross-sectional study was conducted with 562 45–64-year-old postmenopausal women who presented to a Family Health Center. To collect the data, the Descriptive Information Form and Food Frequency Questionnaire were used. In the data analysis, numbers, percentages, mean, standard deviation and multiple linear regression analysis were used.

The multiple linear regression analysis demonstrated that dietary putrescine intake was negatively associated with systolic blood pressure (ß = −0.179, p < 0.001), dietary spermidine intake was positively associated with waist circumference (WC) (ß = 0.142, p = 0.013), systolic blood pressure (ß = 0.188, p = 0.001), diastolic blood pressure (ß = 0.218, p < 0.001), body mass index (BMI) (ß = 0.169, p = 0.003) and waist-to-height ratio (WHtR) (ß = 0.156, p = 0.006), and dietary spermine intake was negatively associated with WC (ß = −0.158, p = 0.003), systolic blood pressure (ß = −0.195, p < 0.001), BMI (ß = −0.107, p = 0.042) and WHtR (ß = −0.138, p = 0.009).

Owing to the study’s cross-sectional nature, the lack of succession in the cause–effect relationship, the use of self-report Food Frequency Questionnaire to determine dietary polyamine intake and the inability to analyze seasonal differences are among the limitations of the study.

In this study, an association was determined between dietary polyamines, metabolic risk parameters and anthropometric measurements. The findings suggest that dietary polyamines in human health should be further investigated owing to the increasing metabolic risk parameters.

The purpose of this work is to apply and compare surrogate-assisted and multi-fidelity, multi-objective optimization (MOO) algorithms to simulation-based aerodynamic design exploration.

The three algorithms for multi-objective aerodynamic optimization compared in this work are the combination of evolutionary algorithms, design space reduction and surrogate models, the multi-fidelity point-by-point Pareto set identification and the multi-fidelity sequential domain patching (SDP) Pareto set identification. The algorithms are applied to three cases, namely, an analytical test case, the design of transonic airfoil shapes and the design of subsonic wing shapes, and are evaluated based on the resulting best possible trade-offs and the computational overhead.

The results show that all three algorithms yield comparable best possible trade-offs for all the test cases. For the aerodynamic test cases, the multi-fidelity Pareto set identification algorithms outperform the surrogate-assisted evolutionary algorithm by up to 50 per cent in terms of cost. Furthermore, the point-by-point algorithm is around 27 per cent more efficient than the SDP algorithm.

The novelty of this work includes the first applications of the SDP algorithm to multi-fidelity aerodynamic design exploration, the first comparison of these multi-fidelity MOO algorithms and new results of a complex simulation-based multi-objective aerodynamic design of subsonic wing shapes involving two conflicting criteria, several nonlinear constraints and over ten design variables.

The key to the production of high quality multilayer PWBs lies in a clear understanding of the many interactions between the chemical and mechanical processing involved. This describes some of these interactions, namely those between oxide treatment, lamination and drilling and the subsequent chemical processing steps, up to, and including, copper electroplating. Choice of oxide treatment has consequences that are not limited to the lamination and drilling operations. Process problems, such as ‘pink ring (haloing)’ are discussed in the context of their sensitivity to particular stages in the manufacturing process.

The electromagnetic field and cooling system of a high power switched reluctance motor (SRM) are studied numerically. The geometry of the motor and its main components are established using a computer-aided design software in the actual size. This study aims to evaluate the resulting thermal losses using the electromagnetic analysis of the motor.

In the electromagnetic analysis, the Joule’s loss in the copper wires of the coil windings and the iron losses (the eddy currents loss and the hysteresis loss) are considered. The flow and heat transfer model for the thermal analysis of the motor including the conduction in solid parts and convection in the fluid part is introduced. The magnetic losses are imported into the thermal analysis model in the form of internal heat generation in motor components. Several cooling system approaches were introduced, such as natural convection cooling, natural convection cooling with various types of fins over the motor casing, forced conviction air-cooled cooling system using a mounted fan, casing surface with and without heat sinks, liquid-cooled cooling system using the water in a channel shell and a hybrid air-cooled and liquid-cooled cooling system.

The results of the electromagnetics analysis show that the low rotational speed of the motor induces higher currents in coil windings, which in turn, it causes higher copper losses in SRM coil windings. For higher rotational speed of SRM, the core loss is higher than the copper loss is in SRM due to the higher frequency. An air-cooled cooling system is used for cooling of SRM. The results reveal when the rotational speed is at 4,000 rpm, the coil loss would be at the maximum value. Therefore, the coil temperature is about 197.9°C, which is higher than the tolerated standard temperature insulation material. Hence, the air-cooled system cannot reduce the temperature to the safe temperature limitation of the motor and guarantee the safe operation of SRM. Thus, a hybrid system of both air-cooled and liquid-cooled cooling system with mounting fins at the outer surface of the casing is proposed. The hybrid system with the liquid flow of Re = 1,500 provides a cooling power capable of safe operation of the motor at 117.2°C, which is adequate for standard insulation material grade E.

The electromagnetic field and cooling system of a high power SRM in the presence of a mounted fan at the rear of the motor are analyzed. The thermal analysis is performed for both of the air-cooled and liquid-cooled cooling systems to meet the cooling demands of the motor for the first time.

The purpose of this paper is to investigate the inhibiting properties of six quaternary ammonium salts, three cationic surfactants and two non‐ionic surfactants in 2 M KOH. An attempt also was made to correlate some molecular parameters of these compounds with their corrosion inhibitor efficiency.

The inhibition efficiencies of quaternary ammonium salts, cationic surfactants and non‐ionic surfactants on the corrosion of zinc in 2 M KOH solution were investigated by potentiodynamic polarisation, electrochemical impedance spectroscopy and linear polarisation methods.

Inhibition efficiencies of quaternary ammonium salts were found to be due to physical absorption on the cathodic sides of zinc electrode and dependence of inhibition efficiencies on substituents were found. Physical adsorption of cationic surfactants on zinc electrode slowed down both anodic and cathodic reactions; thus they were found to be mixed type inhibitors. On the other hand, inhibition behaviour of non‐ionic surfactants was found to be due to adsorption on zinc via polar groups. It was found that non‐ionic surfactants behaved as mixed type inhibitors.

Clarifies the role of molecular structure and substituents on the inhibition efficiency of surfactants and quaternary ammonium compounds on the corrosion of zinc in alkaline media.

Sixty‐six male Japanese students verbally interacted with a confederate opponent, who expressed unreasonable requests politely or impolitely. Half of the participants was pressed to respond immediately, while the other half was not. Personality variables were found to determine the participants' responses to the conflict in interactions with the situational variables; that is, verbal aggressiveness increased hostile responses only when the confederate behaved in an impolite manner, and self‐monitoring increased integrative responses only when the participants were not pressed to respond quickly.

The purpose of this paper was to investigate the impact of specific carbohydrate restriction (polysaccharides and disaccharides) in the form of the specific carbohydrate diet (SCD) in treating irritable bowel syndrome (IBS).

A female patient diagnosed with diarrhea predominant IBS was assigned to the SCD for six months. The diet occurred in phases and was advanced based on the individual’s tolerance level under the guidance of a registered dietitian. Quality of life was measured by a pre- and post-IBS severity score questionnaire. Gastrointestinal symptoms were measured by self-assessment of IBS symptoms using a seven-point Likert-like scale, with −3 = substantially worse to +3 = substantially better. Probiotics were consumed throughout the duration of the study.

The quality of life severity score significantly improved from a severity of 315 (with 500 being the most severe) to 15. The initial symptoms from the first day on the diet compared to the total period for bloating, abdominal pain/discomfort, flatulence/wind, diarrhea, bowel urgency, stool consistency, stool frequency, energy levels, incomplete evacuation and abdominal rumbling were improved significantly (p < 0.0005). The SCD diet significantly improved the quality of life and IBS symptoms in a female patient with IBS-diarrhea.

This study is the first of its kind to evaluate the efficacy of the SCD to treat IBS. The SCD should be considered a therapeutic option to treating IBS after fermentable carbohydrate restriction.

Because of their relationship‐oriented values, avoiding conflict is thought to be particularly prevalent and appropriate in collectivist societies like China Although research in the West has assumed that avoiding conflict is one approach and a largely ineffective one, collectivists may use conflict avoidance in different ways, including protecting the other protagonist. Eighty‐five managers and employees in six State Owned Enterprises in South China described concrete incidents when they avoided conflict and responded to specific items to measure the prior relationship, motivation, strategies, and consequences. Results identify major motivations and strategies used in conflict avoidance. Findings indicate that Chinese managers and employees relied upon the other person, promoted task productivity, and strengthened the relationship when they had a prior strong relationship and cooperative goals. Cooperative goals and fear of revenge were both found to underlie outflanking (trying to work around the other). Results were interpreted as indicating that avoiding conflict can be useful and even reaffirm an already effective relationship, but like open conflict, it must be managed constructively.

The purpose of this paper is to develop a process chain for design and manufacture of endplates of intervertebral disc implants, with specific emphasis on designing footprint profiles and matching endplate geometry.

Existing techniques for acquiring patient‐specific information from CT scan data was and a user‐friendly software solution was developed to facilitate pre‐surgical planning and semi‐automated design. The steps in the process chain were validated experimentally by manufacturing Ti6Al4 V endplates by means of Direct Metal Laser Sintering to match vertebrae of a cadaver and were tested for accuracy of the implant‐to‐bone fitment.

Intervertebral disc endplates were successfully designed and rapid manufactured using a biocompatible material. Accuracy within 0.37 mm was achieved. User‐friendly, semi‐automated design software offers an opportunity for surgeons to become more easily involved in the design process and speeds up the process to more accurately develop a custom‐made implant.

This research is limited to the design and manufacture of the bone‐implant contacting interface. Other design features, such as keels which are commonly used for implant fixation as well as the functionality of the implant joint mechanics were not considered as there may be several feasible design alternatives.

This research may change the way that current intervertebral disc implants are designed and manufactured.

Apart from other areas of application (cranial, maxillofacial, hip, knee, foot) and recent research on customized disc nucleus replacement, very little work has been done to develop patient‐specific implants for the spine. This research was conducted to contribute and provide much needed progress in this area of application.