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An integrated sensor with three elements (zinc oxide, tin oxide and tungsten oxide) was fabricated by thick film techniques in order to develop a smell sensor. Using this sensor and pattern recognition method, the possibility of identifying 15 chemical compounds which belong to the alcohol, ester, ketone, benzene and hydrocarbon group was examined. The following results were obtained: All 15 compounds have different patterns, so they can be individually identified; compounds which have the same functional groups have similar patterns; and, when gas sensitivity of three elements is displayed in a three‐dimensional space, the compounds with the same functional group form a specific closed space. This indicates that the sensor can identify functional groups of chemical compounds.

Describes the parameter estimation procedures for the non‐linear finite element analysis using the hierarchical neural network. These procedures can be classified as the neural network based inverse analysis, which has been investigated by the authors. The optimum values of the parameters involved in the non‐linear finite element analysis are generally dependent on the configuration of the analysis model, the initial condition, the boundary condition, etc., and have been determined in a heuristic manner. The procedures to estimate such multiple parameters consist of the following three steps: a set of training data, which is produced over a number of non‐linear finite element computations, is prepared; a neural network is trained using the data set; the neural network is used as a tool for searching the appropriate values of multiple parameters of the non‐linear finite element analysis. The present procedures were tested for the parameter estimation of the augmented Lagrangian method for the steady‐state incompressible viscous flow analysis and the time step evaluation of the pseudo time‐dependent stress analysis for the incompressible inelastic structure.

The purpose of this paper is to use the Health and Retirement Study to examine the social security (SS) claiming decision of older Americans, with a focus on the behavior of the unemployed.

Using a duration model first, and a bivariate probit framework then, the author investigates whether older unemployed individuals lacking liquidity use SS benefits as a safety net in order to finance consumption during an unemployment episode, even if they do not retire at the same time. In this way, SS might be thought as a form of unemployment insurance (UI) which would allow them to maintain their standard of living during their job search.

The author finds evidence of a claiming pattern specific to the unemployed: they claim sooner than full-time workers, even when they do not retire at the same time. They also seem to discontinue this behavior when their access to UI is extended, which gives support to the author’s hypothesis that the unemployed workers, who lack liquidity, claim their SS benefits even if they do not wish to retire, as a source of alternative unemployment benefits.

By focusing on the SS claiming behavior of the unemployed rather than on their retirement patterns, this paper sheds light on the social insurance role of SS retirement benefits for unemployed workers who are not willing to retire, but need a new source of income while they continue looking for a job.

The purpose of this paper is to investigate Japanese consumer perceptions of the benefits of consuming fresh leafy vegetables.

An online bulletin board survey was conducted in Japan to collect responses to an open-ended question about reasons for consuming fresh leafy vegetables. A total of 897 responses were analysed using word co-occurrence network analysis. A community detection method and centrality measures were used to interpret the resulting network map.

Using a community detection algorithm, the authors identify six major groups of words that represent respondents’ core motives for consuming leafy vegetables. While Japanese consumers view health benefits to be most important, sensory factors, such as texture, colour, and palatability, and convenience factors also influence attitudes. The authors find that centrality measures can be useful in identifying keywords that appear in various contexts of consumer responses.

This is the first paper to use a quantitative text analysis to examine consumer perceptions for fresh leafy vegetables. The analysis also provides pointers for creating visually interpretable co-occurrence network maps from textual data and discusses the role of community structure and centrality in interpreting such maps.

This paper aims to propose a fast and robust 3D point set registration method for pose estimation of assembly features with few distinctive local features in the manufacturing process.

The distance between the two 3D objects is analytically approximated by the implicit representation of the target model. Specifically, the implicit B-spline surface is adopted as an interface to derive the distance metric. With the distance metric, the point set registration problem is formulated into an unconstrained nonlinear least-squares optimization problem. Simulated annealing nested Gauss-Newton method is designed to solve the non-convex problem. This integration of gradient-based optimization and heuristic searching strategy guarantees both global robustness and sufficient efficiency.

The proposed method improves the registration efficiency while maintaining high accuracy compared with several commonly used approaches. Convergence can be guaranteed even with critical initial poses or in partial overlapping conditions. The multiple flanges pose estimation experiment validates the effectiveness of the proposed method in real-world applications.

The proposed registration method is much more efficient because no feature estimation or point-wise correspondences update are performed. At each iteration of the Gauss–Newton optimization, the poses are updated in a singularity-free format without taking the derivatives of a bunch of scalar trigonometric functions. The advantage of the simulated annealing searching strategy is combined to improve global robustness. The implementation is relatively straightforward, which can be easily integrated to realize automatic pose estimation to guide the assembly process.

Drawing on original and published research this paper seeks to examine the current situation of eco‐labelling in Japan, and the possible roles of two connected non‐governmental organizations (NGOs) – the Marine Stewarship Council (MSC) and the World Wildlife Fund (WWF) – may have in future decision making.

A mixed‐method survey approach is used. Two quantitative surveys are followed by unstructured interviews of stakeholders in fisheries and eco‐labelling policy.

Environmental values of Japanese seafood consumers are complex and not explained by any one demographic factor. Environmental problems are becoming complex, and solutions are being sought from beyond the bureaucratic circles, including NGOs. However, neither WWF nor MSC are important stakeholders in policy decisions, but their influence is growing, particularly through relationships with private sector.

Interviews do not offer a representative sample; important inferences but not causative conclusions can be made.

The paper contributes new findings on environmental values, MSC products, and the decision making situation surrounding seafood eco‐labels in Japan.

The purpose of this paper was to synthesise a thermally expandable microsphere (TEMS) with fast thermal response property and small expansion temperature range, and investigate the factors affecting the expansion properties of the microspheres.

A new kind of TEMS with fast thermal response property was synthesised by suspension polymerisation method, using acrylonitrile, ethyl methacrylate and methacrylic acid as the main monomers; Mg(OH)₂ as the main dispersing agent; and isooctane or n-hexane or n-pentane as the blowing agent.

The TEMS possessed the best expansion capacity when encapsulated isooctane and n-hexane were about 18.5 Wt.%. The expansion process of the TEMS could be finished by raising the temperature to 18°C from the expansion onset, much less than the reported 30-50°C. The morphology of the TEMS turned from sphere to irregular concave shape following the content increase of the blowing agent.

A new kind of TEMS composed of acrylonitrile/ethyl methacrylate/methacrylic acid as the polymer shell was synthesised. These TEMS showed the fastest thermal response speed reported.

The purpose of this paper is to introduce a new method called simultaneous elimination and back-substitution method (SEBSM) to solve a system of linear equations as a new finite element method (FEM) solver.

In this paper, a new technique assembling the global stiffness matrix will be proposed and meanwhile the direct method SEBSM will be applied to solve the equations formed in FEM.

The SEBSM solver for FEM with the present assembling technique has distinct advantages in both computational time and memory space occupation over the conventional methods, such as the Gauss elimination and LU decomposition methods.

The developed solver requires less memory space no matter the coefficient matrix is a typical sparse matrix or not, and it is applicable to both symmetric and unsymmetrical linear systems of equations. The processes of assembling matrix and dealing with constraints are straightforward, so it is convenient for coding. Compared to the previous solvers, the proposed solver has favorable universality and good performances.

The purpose of this paper is to see if edutainment containing only healthy food can change children’s preferences and food choices toward healthy eating, especially in overweight or obese children, and if the children’s self-regulation, emotional overeating and parents that use food as a reward would influence those changes. This is important because childhood obesity is one of the biggest public health problems of the 21st century.

The authors conducted a study in two public schools (total 189 children) with a between-subjects experimental design (control vs experimental group), where children in experimental group watched an episode of Nutri Ventures series without unhealthy foods.

The results showed no differences in both children’s preferences and children’s food choices between the control and experimental group, with exception of older children, and contrary to our expectations. Older children in the experimental group chose more unhealthy food than children in the control group. The authors also saw differences in food choices between “emotional overeating” groups, where the children in “high” group tended to choose less healthy food items, especially in the experimental group of children. This leads the authors to believe that isolated edutainment may not be enough to change preferences and food choices; instead it might even have an opposite effect.

This study aimed to identify if edutainment containing only healthy food could be more effective in childhood obesity prevention but instead it showed how complex the whole topic can be.

To design and optimize the traditional aluminum gallium nitride/gallium nitride high electron mobility transistor (HEMT) device in achieving improved performance and current handling capability using the Synopsys’ Sentaurus TCAD tool.

Varying material and physical considerations, specifically investigating the effects of graded barriers, spacer interlayer, material selection for the channel, as well as study of the effects in the physical dimensions of the HEMT, have been extensively carried out.

Critical figure-of-merits, specifically the DC characteristics, 2DEG concentrations and mobility of the heterostructure device, have been evaluated. Significant observations include enhancement of maximum current density by 63 per cent, whereas the electron concentration was found to propagate by 1,020 cm⁻³ in the channel.

This work aims to provide tactical optimization to traditional heterostructure field effect transistors, rendering its application as power amplifiers, Monolithic Microwave Integrated Circuit (MMICs) and Radar, which requires low noise performance and very high radio frequency design operations.

Analysis in covering the breadth and complexity of heterostructure devices has been carefully executed through extensive TCAD modeling, and the end structure obtained has been optimized to provide best performance.