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This paper aims to propose a method to create 3-D finite element meshes automatically using the Delaunay tetrahedralization with the weighted node density technique. Using this method, the adaptive finite element analysis (FEA) was carried out for the calculation of the magnetic field of an eddy current verification model to clarify the usefulness of the method. Moreover, the error evaluation function for the adaptive FEA was also discussed.

The method to create the 3-D finite element meshes using the Delaunay tetrahedralization is realized by the weighted node density technique, and Zienkiewicz-Zhu’s error estimator is used as the error evaluation function of the adaptive FEA.

The magnetic flux density vectors on the node in the error evaluation function for the adaptive FEA should be calculated with the weighted average by the reciprocal of the volume of elements.

This paper describes the method to create 3-D finite element meshes and the comparison among calculation methods of the magnetic flux density vectors on the node for the error estimator.

The interbar current of a squirrel-cage induction motor (IM) flows in the steel sheets when the secondary conductor is not insulated from the laminated steel sheets. It was reported that the interbar current loss was increased when skewing the rotor core. This paper aims to analyze a skewed IM using the three-dimensional (3D) finite element method. The effects of rotor skew on the interbar current are clarified.

In this paper, a skewed squirrel-cage IM is analyzed in three patterns of skewed angle. The calculated results were compared with each other. If all laminated steel sheets are divided by the mesh with actual thickness, the huge calculation time is required. In the method applied in the study, several steel sheets are divided by the mesh with the actual thickness and some steel sheets are assumed to be the steel lump between them to shorten the calculation time.

The paper describes that the distribution of interbar current loss when rotor is skewed is different from that when rotor is not skewed. In addition, the paper suggests that the larger the skew angle becomes, the larger the interbar current loss becomes.

In this paper, a skewed IM with the consideration of the interbar current in the laminated steel sheets was analyzed using the 3D finite element method. The influences of the rotor skew on the interbar current are clarified.

Aims to investigate the eddy current loss in permanent magnets of IPM motors.

Uses the 3D finite element method (3D FEM).

Finds that the effect of the current phase on the eddy current loss is very different according to the number of slots.

Investigates the eddy current loss in a permanent magnet of an IPM motor.

The purpose of this paper is to clarify the electrical loss of an interior permanent magnet (IPM) motor driven by the pulse‐width modulation (PWM) inverter with various carrier frequencies quantitatively.

An IPM motor driven by the PWM inverter was simulated using the three‐dimensional finite‐element method while changing various carrier frequencies of the PWM inverter. The calculated results are compared with the calculated results differing the number of permanent magnet division.

The eddy current loss in the permanent magnets decreases as the carrier frequency increases. In the case of low‐carrier frequency, the eddy current loss greatly decreases as the number of permanent magnet division increases. However, the effect of the eddy current loss decreases by the number of permanent magnet division as the carrier frequency increases.

The paper describes the electrical loss of an IPM motor driven by the PWM inverter with various carrier frequencies.

This paper aims to describe a novel 3D finite element mesh modification method for motors with the skewed rotor in detail, the method having been developed by solving the Laplace equation.

Using the mesh of the skewed squirrel‐cage induction motor created by the novel method, the torque, the bar‐current, the electrical losses and so on are analyzed by the 3D finite element method.

It was found that the torque ripple, the bar‐current ripple and the losses of the motor with the skewed rotor are smaller than those of the motor with the no‐skewed rotor. In addition, the validity of the analysis is clarified by comparing the calculated and the measured results.

The usefulness of the method is clarified by the 3D finite element analysis of a skewed squirrel‐cage induction motor.

The purpose of this paper is to clarify the usefulness of characteristics analysis of an interior permanent magnet (IPM) motor using the 3‐D finite element method (FEM) with prismatic elements from the view point of the accuracy and the calculation time.

The authors analyzed characteristics of an IPM motor applied by the pulse width modulation (PWM) voltage source using the 3‐D FEM with prismatic elements and with tetrahedral elements; then compared the calculated results and the calculation time using prismatic elements with those using tetrahedral elements.

It was found that the calculated current and torque, and eddy current loss using prismatic elements are almost the same as those using tetrahedral elements. The calculation time using prismatic elements is shorter than that using tetrahedral elements.

This paper verifies the usefulness of the 3‐D FEM with prismatic elements through characteristics analysis of an IPM motor driven by the PWM voltage source.

The purpose of this paper is to develop a dynamic analysis method of a novel spherical resonant actuator. In this method, the magnetic field equation is coupled with the electric circuit equation and the motion equation with the mesh modification method using the Laplace equation applied to the rotation of the spherical actuator.

The static torque characteristics and dynamic characteristics of the spherical resonant actuator using the proposed method are clarified. The calculated results are compared with the measured ones.

The calculated static torque agrees well with the measured one. The validity of the computation using the proposed method is quantitatively clarified through the comparison with the measurement.

The paper proposes the dynamic analysis method of the complicated spherical resonant actuator using the mesh modification method by the Laplace equation.

Using the forensic investigation (FORIN) approach, the purpose of this paper is to identify the factors that exacerbated the loss of human life in one of the most devastated local municipalities on the coast by 2011 Great East Japan Earthquake and Tsunami (GEJET) disaster.

This paper begins by reviewing the extent of damage to the local municipalities along the Sanriku ria coast, which has a long history of tsunami disasters. Second, the paper compares previous major tsunami events by using a human vulnerability index, and applies this index to detect the city of Rikuzentakata. Third, the paper identifies the root causes of the GEJET disaster in the city. Interview records with disaster victims were used to elucidate the main factors that exacerbated the number of deaths.

The study indicates that the FORIN approach can be effectively applied to identify the target city for this case study and to point to those factors the most exacerbated human sufferings, and also provides many lessons based on research findings and methodologies to support building resilient societies in the future.

This paper indicates FORIN approach as an effective research template by investigating the GEJET disaster.

After completion of the case study, students will be able to: 1. understand the basis for developing global supply chains for exploring international markets, 2. identify the various sources of geopolitical risk while expanding globally, 3. assess the market entry or exit decisions from a principled and commercial perspective and 4. identify and weigh different options when faced with an exit situation under conditions of geopolitical risk.

The Japanese fast fashion brand Uniqlo opened 45 stores in Russia as a part of its international retail expansion strategy. The brand provided affordable fashion for everyone. However, the Russia–Ukraine armed conflict had put the company in a dilemma. The Japanese Government and the public joined the broader global community in condemning Russia’s armed intervention in Ukraine. These countries also imposed economic sanctions on Russia, resulting in many multinational companies winding up their operations in Russia. Uniqlo faced a market exit dilemma. Russia had the largest number of Uniqlo stores in Europe. The company CEO also highlighted the necessity of meeting the clothing needs of the Russian people. However, people in Japan and elsewhere considered Russia as an aggressor nation. Any economic link with the Russian market would be ethically wrong, and consumers in Japan, the USA and the European Union might see this as support for Russia’s war efforts. The company had to choose between continuing operations in Russia or exiting the Russian market.

This case study can be used in basic marketing management and international business courses to discuss the market attractiveness and risk aspects for market entry or exit decisions. It can also be used in advanced courses such as strategic management, global strategy and global political economy, highlighting the impact of geopolitical conflicts on business operations.

Teaching notes are available for educators only.

CSS 11: Strategy.

The authors analyzed data and information mainly from the company’s annual reports and the books written by the CEO.

How and when can a “value” brand upscale its brand image? In the wake of the financial crisis of 2007–2008, UNIQLO – Japan’s street fashion brand – considered introducing a new brand collaboration. They needed to capture the attention of younger, more fashionable consumers. However, people were tightening their spending as they faced uncertainties related to their jobs and wealth. Even though UNIQLO had had a steady growth in sales for the previous 24 years, it was questionable whether it was strategically a good time to launch a premium brand collaboration. And if so, who was the right partner? High-end designer Jil Sander, fashionable New York-based Theory or emerging French “casual luxury” brand Comptoir des Cotonniers?

This case is about the challenges faced by a low-priced brand to collaborate with a high-end brand to enhance the brand image. It explores the important elements to take into consideration when evaluating launching collaboration using the high-end brand’s name. The students will learn how to examine the risks and benefits of creating a new image for the core brand. If the students had learnt branding or brand extension before, this case can be used to teach how consumer’s perception affects brand extension and the target market’s impact on pricing and distribution strategies. It can be used for a marketing course at the MBA level to explore the concepts in a growing company’s brand image or an undergraduate specialized course in brand management or marketing management. The students also learn how the fashion industry’s supply chain management works to adapt to rapidly changing fashion trends.