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This paper describes an automated design system for nuclear structural components under complicated loading conditions. As a basic strategy of designing structures considering various loading conditions, the “generate and test” strategy is adopted because of simplicity and broad applicability. The object‐oriented knowledge representation technique is adopted to store knowledge modules related to design problems, while the data‐flow processing technique is utilized as an inference mechanism among the knowledge modules. As efficient design modification mechanisms, the present system utilizes two approaches, (a) an empirical approach based on experts’ empirical knowledge and the fuzzy control, and (b) a mathematical approach based on numerical sensitivity analysis. Using the present system, one can also obtain a “design window” which designates a satisfaction area for all design criteria in a design variable space. The fundamental performances of this system are clearly demonstrated through the design of a two‐dimensional model of the fusion first wall with a circular cooling channel.

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.

In aerospace applications, due to the severe limitations on the weight and space envelope, it is mandatory to use high performance compact heat exchangers (CHEs) for enhancing the heat transfer rate. The most popularly used ones in CHEs are the plain fins, offset strip fins (OSFs), louvered fins and wavy fins. Amongst these fin types, wavy and offset fins assume a lot of importance due to their enhanced thermo‐hydraulic performance. The purpose of this paper is to investigate the influence of geometrical fin parameters, in addition to Reynolds number, on the thermo‐hydraulic performance of OSFs.

A computational fluid dynamics approach is used to conduct a number of numerical experiments for determination of thermo‐hydraulic performance of OSFs considering the various geometrical parameters, which are generally used in the aerospace industry. These investigations include the study of flow pattern for laminar, transition and turbulent regions. Studies are conducted with different fin geometries and comparisons are made with available data in open literature. Finally, the generalized correlations are developed for OSFs taking all geometrical parameters into account for the entire range of operations of the aerospace industry covering laminar, transition and turbulent regions. In addition, the effects of various geometrical parameters are presented as parametric studies.

Thermo‐hydraulic design of CHEs is strongly dependent upon the predicted/measured dimensionless performance (Colburn factor “j” and Fanning friction “f” vs Reynolds number Re) of heat transfer surfaces. Several types of OSFs used in the compact plate‐fin heat exchangers are analyzed numerically.

The present numerical analysis is carried out for “air” media and hence these results may not be accurate for other fluids with large variations of Prandtl numbers.

In open literature, these fins are generally evaluated as a function of Reynolds number experimentally, which are expensive. However, their performance will also depend to some extent on geometrical parameters such as fin thickness, fin spacing, offset fin length and fin height.

This numerical estimation can reduce the number of tests/experiments to a minimum for similar applications.

A theoretical study is performed on three‐dimensional, heat transfer and fluid flow in radially rotating heated channels with steady, laminar throughflow. Consideration is given to the channel of different geometry. Both the rotational speed and throughflow rate are varied. The flow is hydrodynamically and thermally developing, with a constant wall heat flux. The velocity‐vorticity method is employed in the formulation and numerical results are obtained by means of a finite‐difference technique. The Nusselt number, friction factor, and temperature and velocity distributions are determined, and the role of the Coriolis force on the entrance‐region transport phenomena is investigated. Results are compared with the existing literature.

The Japanese legal system has several significant, deep-rooted and widely recognised flaws, one of which has been a history of weak support for the needs of victims of sexual violence. This structure of prosecutorial apathy has meant that female victims, and wider society, have been insufficiently protected from all but the most extreme cases of abuse and assault. However, a growing political interest in gender equality and the nascent development of a Japanese #MeToo movement has brought more pressure for reforms, with 2017 seeing the first significant change of Japan's sex crime laws in 110 years. Despite this, many serious flaws remain to be addressed, including: concerns over the statute of limitations for sexual crimes, the manner in which vague legal definitions can prevent the law from being effectively applied, the lack of support for victims, and the often arbitrary standards for prosecution and the settlement system that allows the wealthy to avoid more than cursory punishment. This chapter examines the efforts to introduce reforms and the extent to which such changes are likely to have a positive impact on the well-being, safety and legal rights of Japanese women.

The knowledge about the heat transfer and flow field in the ribbed internal passage is particularly important in industrial and engineering applications. The purpose of this paper is to identify and analyze the performance of the constrained large-eddy simulation (CLES) method in predicting the fully developed turbulent flow and heat transfer in a stationary periodic square duct with two-side ribbed walls.

The rib height-to-duct hydraulic diameter ratio is 0.1 and the rib pitch-to-height ratio is 9. The bulk Reynolds number is set to 30,000, and the bulk Mach number of the flow is chosen as 0.1 in order to keep the flow almost incompressible. The CLES calculated results are thoroughly assessed in comparison with the detached-eddy simulation (DES) and traditional large-eddy simulation (LES) methods in the light of the experimentally measured data.

It is manifested that the CLES approach can predict both aerodynamic and thermodynamic quantities more accurately than the DES and traditional LES methods.

This is the first time for the CLES method to be applied to simulation of heat and fluid flow in this widely used geometry.

Existing research suggests that preservice elementary teachers tend to believe “good” citizens are people who follow laws and help others rather than people who embrace a more active model of citizenship that includes working to improve society. The purpose of this paper is to propose that this trend results from a self-perpetuating cycle of passive citizenship that develops in part due to state curriculum standards and school experiences which focus on transmitting knowledge rather than preparing students to be active agents of change.

The paper presents the results of action research conducted in a teacher preparation course; the research was designed to investigate the impact of a systematic effort to see if preservice teachers’ perspectives could be broadened to include a social justice perspective.

As a result of the findings, the authors argue that to counteract the cycle of passive citizenship, education to create a more socially just world must be a collective responsibility shared by teachers at all levels, K-16.

This is original research that examines an approach to end a cycle of passive citizenship by promoting social justice.

The purpose of this paper is to understand the usefulness of an agile social learning method in higher education to build capacity for sustainable development at the community level. Social learning methods intend to empower students (and instructors) to work together in connection with real-life issues – combined with acquiring a conceptual understanding – to analyze issues at hand and work out solutions. The agile format of the method was aimed at a subject that is adaptive and responsive to change to empower the students to take action toward sustainable development.

This study was based on a case study methodology where the running of the subject was documented and analyzed for two years. The target student group was maritime professionals who had an interest or were in a position to work with developing sustainable solutions in their home organizations (mostly in developing countries).

The results of the analysis indicate how the students learned about environmental, social and economic spheres of sustainable development and their linkages; how the subject format stimulated the students to develop different “learning paths” between the three spheres of sustainable development, which enabled a multi-faceted understanding of sustainable development issues; and, finally, how the students were able to design evolvable sustainable development solutions.

The results indicate both the novelty and usefulness of the agile social learning method to build capacity for sustainable development through the subject designed for higher education.

The purpose of this paper is to augment heat transfer rates of traditional rib-elements with minimal pressure drop penalties.

The novel geometries in the present research are conventional cylindrical ribs with rounded transitions to the adjacent flat surfaces and with modifications at their bases. All turbulent fluid flow and heat transfer results are presented using computation fluid dynamics with a validated v2f turbulence closure model. Turbulent flow characteristics and heat transfer performances in square channels with improved ribbed structures are numerically analyzed in this research work.

Based on the results, it is found that rounded transition cylindrical ribs have a large advantage over the conventional ribs in both enhancing heat transfer and reducing pressure loss penalty. In addition, cylindrical ribs increase the flow impingement at the upstream of the ribs, which will effectively increase the high heat transfer areas. The design of rounded transition cylindrical ribs and grooves will be an effective way to improve heat transfer enhancement and overall thermal performance of internal channels within blade cooling.

The novel geometries in this research are conventional cylindrical ribs with rounded transitions to the adjacent flat surfaces and with modifications at their bases. The combination of cylindrical ribs and grooves to manipulate the turbulent flow.

The aim of this paper is to study two-dimensional numerical simulations of the flow and temperature fields inside the bend (turn) part of a U-duct.

Several turbulence models based on two and five equations were used to solve the momentum and energy equations inside the bend (turn) part of the U-duct. For two-equation models, both the renormalization group and realizable k-ɛ turbulence models were implemented. The five-equation model used is a Reynolds stress model with different wall boundary conditions. Standard, non-equilibrium and enhanced wall functions were used in parallel with the two- and five-equation models to treat the turbulent flow near the duct walls.

Several turbulence models were used to simulate the flow and temperature fields along the bend part of a U-duct with different inlet and thermal boundary conditions. The numerical results indicate that the renormalization and realizable k-ɛ turbulence models with standard wall function treatment gave the best results when compared with experimental data obtained for similar conditions.

For heat transfer analysis, two different thermal boundary conditions, i.e. constant wall temperature and constant heat flux at the wall are implemented. The results are calculated for Reynolds number equal 20,000.

The results can be used in designing heat exchangers, piping and duct systems, and internal passage cooling of gas turbine blades.

The numerical results obtained here concentrate on the detailed investigation of flow and temperature field at the outer wall of the bend part. Different boundary conditions at the inlet and the outer bend walls of the U-duct were applied to study how these boundary conditions affect the flow and temperature fields.