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The purpose of this paper is to provide an approach to the optimal design of open type magnetic circuit of permanent magnet having uniform field.

The Biot‐Savart's law and evolution strategy are used for the design of permanent magnet configuration. The optimization is carried out by changing the objective function, dimension of target region, and target flux density.

The obtained uniformity is affected by the selection of objective function, dimension of target region, and target flux density. About 50 ppm uniformity of 0.08 T in the imaging area is obtained by changing the dimensions, dimension of target region, and target flux of 3D magnets and the amplitudes of magnetization and the directions of magnetization vectors.

This paper describes a new approach for obtaining the optimal shape of open type magnetic circuit which may be used when magnetic resonance imaging is carried out.

The aim of this research is to develop, demonstrate and characterize techniques for fabricating such scaffolds by combining solid freeform fabrication and computational design methods. When fully developed, such techniques are expected to enable the fabrication of tissue engineering scaffolds endowed with functionally graded material composition and porosity exhibiting sharp or smooth gradients. Results of bio‐compatibility and in vivo implantation are presented.

The purpose of the paper is to show that how a new magnetic circuit, which the paper could not imagined beforehand, may be obtained using a newly developed ON/OFF topology optimization method by applying it to the design of magnetic head and motor.

ON/OFF optimization technique combined with finite element method.

It is shown that 3-D topology optimization of SPT head, in which the recording head is increased and the leakage flux is decreased, is possible using the proposed method. The optimization of IPM motor with the minimum torque ripple and the maximum toque is also examined.

3-D ON/OFF optimization method applied to practical problems considering the nonlinearity and rotation of rotor, etc.

The purpose of this paper is to propose the speed-up of the fixed-point method by updating the reluctivity at each iteration (this is called a modified fixed-point method).

A modified fixed-point method, which updates the derivative of reluctivity at each iteration, is proposed. It is shown that the formulation of the fixed-point method using the derivative of reluctivity is almost the same as that of the Newton-Raphson method. The convergence characteristic of the newly proposed fixed-point method is compared with those of the Newton-Raphson method.

The modified fixed-point method has an advantage that the programming is easy and it has a similar convergence property to the Newton-Raphson method for an isotropic nonlinear problem.

This paper presents the formulation and convergence characteristic of the modified fixed-point method are almost the same as those of the Newton-Raphson method.

So far the literature on inverse shape design in aerodynamics is still confined to the single‐point (nominal design point) design and to steady flow. This situation cannot cope with the modern development of internal and external aerodynamics and aerothermoelasticity, especially turbomachinery and aircraft flows. Accordingly, in recent years a new generation of inverse shape design problem has been suggested and investigated theoretically and computationally, consisting mainly of: unsteady inverse and hybrid problems; multipoint inverse and hybrid problems; and inverse problem in aerothermoelasticity. It opens a new area of research in fluid mechanics and aerothermoelasticity. An overview of its status and perspective is given herein, emphasizing the new concepts, theory and methods of solution involved.

Children living in agricultural areas are exposed to pesticides in their living areas and through activities of daily living. These exposures may lead to adverse health effects. The purpose of this paper is to investigate household environmental and behavioural factors associated with chlorpyrifos exposure and resultant adverse health effects in children living in an agricultural community.

A cross-sectional study was conducted including 65 toddlers (age of 12–36 months) and their parents were face-to-face interviewed from January to February 2016. Toddler’s hands and feet, toys and floors were wiped for chlorpyrifos residue analysis. The wipes were extracted and analysed by gas chromatography with a flame photometric detector, and blood cholinesterase activity was measured by the EQM Test-mate (model 400).

The average age (± standard deviation) of children was 19.9 (±5.9) months. Chlorpyrifos detections were 61.5 per cent (hands), 57.1 per cent (toys), 53.8 per cent (floors) and 30.8 per cent (feet). The highest chlorpyrifos residue concentration was detected on toy surface (3.022 µg/m²). Chlorpyrifos residues on hands and feet were positively correlated with concentrations on floors and toys (Spearman’s ρ, p<0.01). Multiple linear regression analysis revealed that more frequent hand washing (β=−0.236, p=0.067) and showering (β=−0.240, p=0.056) was negatively associated with chlorpyrifos residue on children’s body. House cleaning frequency was significantly associated with an increase in haemoglobin-adjusted erythrocyte cholinesterase (β=0.251, p<0.05).

Chlorpyrifos exposures found in the children household area through their activities and behaviours can cause several adverse health effects. The circumstances associated with chlorpyrifos exposure should be mitigated and reduced to improve the household environment of children living agricultural areas.