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The purpose of this paper is to develop a robot vision system for surface defect detection of 3D objects. It aims at the ill‐defined qualitative items such as stains and scratches.

A robot vision system for surface defect detection may counter: high surface reflection at some viewing angles; and no reference markers in any sensed images for matching. A filtering process is used to separate the illumination and reflection components of an image. An automatic marker‐selection process and a template‐matching method are then proposed for image registration and anomaly detection in reflection‐free images.

Tests were performed on a variety of hand‐held electronic devices such as cellular phones. Experimental results show that the proposed system can reliably avoid reflection surfaces and effectively identify small local defects on the surfaces in different viewing angles.

The results have practical implications for industrial objects with arbitrary surfaces.

Traditional visual inspection systems mainly work for two‐dimensional planar surfaces such as printed circuit boards and wafers. The proposed system can find the viewing angles with minimum surface reflection and detect small local defects under image misalignment for three‐dimensional objects.

The aim of this paper is to create a sensor that can measure the contact status with high‐resolution than ever.

This paper proposes a new type of optical tactile sensor that can detect surface deformation with high precision by using the principle of optical lever. A tactile sensor is constructed that utilizes the resolution of a camera to the maximum by using transparent silicone rubber as a deformable mirror surface and taking advantage of the reflection image.

It has been found that the sensor can sense the deformation by the object with 1 percent error rate in simulation. In implementation of this time, the error rate results 10 percent.

This sensor can be used with broad applications by combining with other devices. As one of future work, the zero method will be used by using active patterns and get more accurate information.

Using the transparent silicone rubbers the sensor enables very simple and low cost and high‐resolution detection method. In addition, the simplicity of our sensor results various applications. For example, the transparency makes the sensor a light pathway, so the sensor can be a contactless sensor or an interactive device.

The concept of a tactile sensing method is introduced which can utilize the resolution of a camera to the maximum possible extent and can detect surface deformation by using the principle of optical lever.

This paper aims to examine the uniform diffracted fields from a perfectly magnetic conductive (PMC) surface with the extended theory of boundary diffraction wave (BDW) approach.

Miyamoto and Wolf’s symbolic expression of the vector potential was used in the extended theory of BDW integral. This vector potential is applied to the problem, and the nonuniform field expression found was made uniform. Here, the expression is made uniform, using the detour parameter with the help of the asymptotic correlation of the Fresnel function. The BDW theory for the PMC surface extended the diffracted fields, and the uniform diffracted fields were calculated.

The field expressions obtained were interpreted with the graphs numerically for different aperture radii and observation distances. It has been shown that the BDW is continuous behind the diffracting aperture. There does not exist any discontinuity at the geometrically light-to-shadow transition boundary, as is required by the theory.

The results were graphically compared with diffracted fields for other surfaces. As far as we know, the uniform diffracted fields from the circular aperture on a PMC surface were calculated for the first time with the extended theory of the BDW approach.

The effects which are produced by pearlescent pigments are intimately connected to optics and the interaction of light with matter. Pearlescent pigments are optical filters which reflect and transmit light which falls upon them. In order to understand pearlescent pigments, therefore it is first necessary to understand some of the basic laws of optics. I would like to review some of these laws to talk about light and its interaction with matter, how it can be separated into its components, the laws of reflection and refraction and how all of these laws apply to pearlescent pigments.

This paper reports a study on reflection measurement of a textile surface. The measurement was made involving spatial directions and wavelength. To integrate a spectral detector with a setup for different lighting and viewing directions, the method of fixed sample normal is proposed. In this method, the sample's surface normal is fixed and various lighting and viewing directions are obtained by relocating the source and detector. A visualization system was developed to help explore the measured data. The system allows the user to select a measured data point to display simultaneously the spectrum and its associated color and angle information. Finally, a new interpolation method based on space partition was proposed. Given an interpolation point P, the space is subdivided into subspaces and the data point closest to P in each subspace is selected. This generates a set of points and tetrahedrons, and if any tetrahedron contains P, it will be used for the interpolation based on the barycentric coordinates. This study is useful for multiple applications such as realistic image synthesis, verification of reflection models, and investigation of the relationships between textile appearances and the underlying physical parameters.

The purpose of this paper is to analyze and show how to avoid the interference in infrared (IR) temperature field measurement during welding.

First, the hardware used in this experiment is described. In this paper, these interferences are first classified into diffuse and specular reflection based on reflection model, and are restrained, respectively. Finally, IR temperature is calibrated by thermocouple.

The specular reflection is the primary interference which causes high light zone. And it can be transferred out of welding seam when the IR thermography is placed perpendicularly to welding seam.

The paper provides a new IR measure method and detailed analysis about the interferences in applying IR temperature sensing.

Student evaluations of teaching (SETs) are the most frequent form of faculty performance in the classroom, though they tend to be used as summative rather than formative evaluations. In this chapter, a project involving the use of a virtual learning environment for formative, weekly SETs is explored from both the student and faculty point of view at a rural university college in the United Kingdom. This project encouraged student participation in creating the learning environment and faculty reflection on how to improve the student experience. From the student perspective, the weekly anonymous evaluations were useful for providing feedback; however, students tended to only respond if they were not satisfied with the faculty member. The exception to this was that some students were more motivated to complete the evaluation forms if they believed the faculty member was utilising their feedback. From the faculty perspective, the feedback was not as detailed as they had expected, and some questioned whether it was worth the effort of conducting formative evaluations if the response rate was so low. Others used the feedback for reflective purposes, and it was found that those that reflected on their work at higher levels tended to receive a greater year-on-year increase in their end of year teaching evaluations.

The purpose of this paper is to describe how fabricate solar cell based‐on porous silicon (PS) prepared by electrochemical etching process is fabricated and the effect of porosity layer on the solar cell performance is investigated.

The techniques used include SiO₂ thermal oxidation, ZnO/TiO₂ sputtering deposition and PS prepared by electrochemical etching. Surface morphology and structural properties of porous Si were characterized by using scanning electron microscopy. Photoluminescence and Raman spectroscopy measurements were also performed at room temperature. Current‐voltage measurements of the fabricated solar cell were taken under 80 mW/cm² illumination conditions. Optical reflectance was obtained by using optical reflectometer (Filmetrics‐F20).

Pore diameter and microstructure are dependent on anodization condition such as HF: ethanol concentration, duration time, temperature, and current density. On other hand, a much more homogeneous and uniform distribution of pores is obtained when compared with other wafer prepared with different electrolyte composition.

PS is found to be an excellent anti‐reflection coating against incident light when it is compared with another anti‐reflection coating and exhibits good light‐trapping of a wide wavelength spectrum which produce high efficiency solar cells (11.23 per cent).

It is a huge technical and engineering challenge to realize the precise assembly of thousands of large optics in high power solid-state laser system. Using the 400-mm aperture-sized transport mirror as a case, this paper aims to present an intelligent numerical computation methodology for mounting performance analysis and modeling of large optics in a high-power laser system for inertial confinement fusion (ICF).

Fundamental principles of modeling and analysis of the transport mirror surface distortion are proposed, and a genetic algorithm-based computation framework is proposed to evaluate and optimize the assembly and mounting performance of large laser optics.

The stringent specifications of large ICF optics place very tight constraints upon the transport mirror’s assembly and mounts. The operational requirements on surface distortion [peak-to-valley and root mean square (RMS)] can be met as it is appropriately assembled by the close loop of assembly-inspection-optimization-fastening. In the end, the experimental study validates the reliability and effectiveness of the transport mirror mounting method.

In the assembly design and mounting performance evaluation of large laser optics, the whole study has the advantages of accurate evaluation and intelligent optimization on nano-level optical surface distortion, which provides a fundamental methodology for precise assembly and mounting of large ICF optics.

Radiative heat transfer in the laminar boundary layer flow of an absorbing, emitting and anisotropically scattering gray fluid over a flat plate, with the surface of the plate reflecting radiation in diffuse‐cum‐specular fashion is analyzed. The discrete ordinates method is used to model the radiative transfer. The governing dimensionless momentum and energy equations, in the form of a partial differential system, are solved by a finite difference method. The effect of various parameters like, emittance, the degree of anisotropy in scattering, scattering albedo and the nature of surface reflection on the total heat flux from the plate to the fluid are studied and results are presented.