An experimental study of the mean effective strain in rod (or bar) rolling process

This paper presents an experimental study that investigates the validity of the analytical model [9] for predicting the mean effective strains associated with bar (or rod) rolling. Designed for this purpose were plate and bar rolling experiments which consist of a four-pass groove (oval and round) rolling sequences, which have material at each pass that experience the same amount of mean effective strain. The microstructure and mechanical behaviors of specimens acquired from two types of rolling experiments at 650°C were compared. A parallelism between the mechanical behaviors of a plate-rolled specimen and a bar-rolled specimen has been found at each pass. We therefore concluded that the analytical model has the underlying rationale to be used in the analysis of the rod (or bar) rolling process.     

Enhanced soft subspace clustering integrating within-cluster and between-cluster information

While within-cluster information is commonly utilized in most soft subspace clustering approaches in order to develop the algorithms, other important information such as between-cluster information is seldom considered for soft subspace clustering. In this study, a novel clustering technique called enhanced soft subspace clustering (ESSC) is proposed by employing both within-cluster and between-class information. First, a new optimization objective function is developed by integrating the within-class compactness and the between-cluster separation in the subspace. Based on this objective function, the corresponding update rules for clustering are then derived, followed by the development of the novel ESSC algorithm. The properties of this algorithm are investigated and the performance is evaluated experimentally using real and synthetic datasets, including synthetic high dimensional datasets, UCI benchmarking datasets, high dimensional cancer gene expression datasets and texture image datasets. The experimental studies demonstrate that the accuracy of the proposed ESSC algorithm outperforms most existing state-of-the-art soft subspace clustering algorithms.     

A novel algorithm for estimation of depth map using image focus for 3D shape recovery in the presence of noise

Three-dimensional shape recovery from one or multiple observations is a challenging problem of computer vision. In this paper, we present a new Focus Measure for the estimation of a depth map using image focus. This depth map can subsequently be used in techniques and algorithms leading to the recovery of a three-dimensional structure of the object, a requirement of a number of high level vision applications. The proposed Focus Measure has shown robustness in the presence of noise as compared to the earlier Focus Measures. This new Focus Measure is based on an optical transfer function implemented in the Fourier domain. The results of the proposed Focus Measure have shown drastic improvements in estimation of a depth map, with respect to the earlier Focus Measures, in the presence of various types of noise including Gaussian, Shot, and Speckle noises. The results of a range of Focus Measures are compared using root mean square error and correlation metric measures.     

Frequency domain lifetime characterization

Time-based measurements are commonly used for lifetime characterization of semiconductors. We have developed the theory, verified by experiment, of frequency-based lifetime characterization as an alternative to time-based measurements for MOS devices biased in inversion. One consideration during lifetime/diffusion length measurements, is whether the near-surface space-charge region or the bulk or quasineutral region is characterized. To characterize the near-surface space-charge region of the device, one usually makes room temperature pulsed MOS capacitor or diode leakage current measurements. We show that room-temperature, frequency-domain capacitance, conductance, or resistance measurements characterize the quasineutral bulk, not the space charge region, in contrast to room-temperature pulsed MOS-C or diode leakage current measurements which characterize the space-charge region     

Signal characteristics of differential-pulsed eddy current sensors in the evaluation of plate thickness

Differential-pulsed eddy current (PEC) signals and their characteristics are investigated as tools for the evaluation of plate thickness by using the reflection-type PEC probe, which consists of an exciter coil and two sensor coils in a differential arrangement. Numerical and experimental signals are first compared to validate numerical simulation results, and good agreement between them is achieved. Investigation of differential PEC signals and their characteristics against thickness and conductivity variations shows that time-related features, such as the time-to-peak and the zero-crossing time, correspond well to plate thickness and conductivity. However, the feature quality of peak value turns out to be very poor. To improve this, the effects of coil characteristics on the input pulse, and consequently on differential PEC signals, are investigated. Results show that the feature quality of peak value may be improved by reducing the time constant, but doing so would worsen the quality of the other two features. Lift-off signals obtained by this probe show that the lift-off point of intersection also appears in the differential reflection-type PEC signals.     

HIP joining of RAFM/RAFM steel and beryllium/RAFM steel for fabrication of the ITER TBM first wall

One of the main research and development issues concerning the test blanket module (TBM) is the development of joining technologies for fabrication of the first wall. The objectives of the present study are to investigate the effects of thermal history corresponding to the TBM fabrication process on reduced activation ferritic martensitic (RAFM) steel microstructure, and to establish the appropriate hot isostatic pressure (HIP) conditions for the fabrication of RAFM/RAFM steels and beryllium (Be)/RAFM steels joints without degradation of the mechanical properties of the RAFM steel or delamination of the joined interface. In this study, RAFM and RAFM steels were joined by HIPing at 1050 °C under 100 MPa for 2 h. During the HIP process, the thermally altered microstructure and mechanical properties were recovered to the as-received state by subsequent normalizing at 950 °C for 2 h and tempering at 750 °C for 2 h. Be and RAFM steels were also bonded successfully by the application of Ti/Cu interlayers and HIPing at 850 °C under 100 MPa for 2 h.     

Development of a usability evaluation framework with quality function deployment: From customer sensibility to product design

The aim of this research was to develop a usability evaluation model based on customer sensation using quality function deployment (QFD), which evaluates the relationship between consumer sensation and usability among the physical design factors of dishwashers. Four aspects of the evaluation model were analyzed with QFD: overall sensation factors, detail sensation factors, usability evaluation factors, and physical design factors of products in 3 sequential processes. The sensation evaluation factors and the usability evaluation factors were created from the results of the sensation and usability tests. Moreover, experts and manufacturers were involved in selecting the physical design factors. With the evaluation model using these 4 aspects, physical design factors influencing user sensation were generated. These factors were Label Icon, Rack Size, Shape of Knob, and LCD size. In addition, the degree of influences was tested and design guidelines derived from the final physical design factors were generated. © 2009 Wiley Periodicals, Inc.     

Effect of tris(methoxy diethylene glycol) borate on ionic conductivity and electrochemical stability of ethylene carbonate-based electrolyte

The effect of tris(methoxy diethylene glycol) borate (TMDGB) on the coordination structure between ethylene carbonate (EC) solvents with high permittivity and ClO₄⁻ anions has been investigated by using a Fourier transform infrared (FT-IR) spectroscopy. The results of FT-IR analyses manifested that the boron atom of TMDGB anion receptor forms the complex with ClO₄⁻ anions. Even though Lewis acid-base interaction between the TMDGB anion receptor and ClO₄⁻ anions in the electrolyte solution lead to the prominent enhancement of both the dissociation degree of lithium salts and the lithium ion transference number, the ionic conductivity of the EC-based electrolyte solution decreased due to the trap of ClO₄⁻ anions by introducing the TMDGB anion receptor.The electrochemical stability of gel polymer electrolyte based on semi-interpenetrating network (IPN) structure with tris(pentafluoro phenyl) borane (TPFPB) or TMDGB anion receptor was obviously improved.     

Transition probabilities of coded BPSK signals for hard-decisiondecoding with k-bit CSI in Nakagami-m fading channels

We evaluate a closed form expression of the transition probabilities used for calculating metric values and pairwise error probabilities of convolutional codes, equipped with coherent BPSK signals, for hard-decision decoding with k-bit channel state information (CSI) in slow varying frequency nonselective Nakagami-m fading channels. It is noted that 1-bit CSI is sufficient to take advantage of channel information under deep fadings