A novel internal thread defect auto-inspection system

This paper describes a novel optical thread plug gauge (OTPG) for internal thread inspection using machine vision. The OTPG is composed of a rigid industrial endoscope, a charge-coupled device camera, and a two degree-of-freedom motion control unit. A sequence of partial wall images of an internal thread are retrieved and reconstructed into a 2D unwrapped image. Then, a digital image processing and classification procedure is used to normalize, segment, and determine the quality of the internal thread. The proposed OTPG provides an orientation-free and convenient method for detecting defects such as scratches, collapses, and flaws in an internal thread.     

Comparison of solvent removal methods of microporous polypropylene tubular membranes via thermally induced phase separation using a novel solvent: Camphene

A novel solvent, camphene, was used to prepare microporous polypropylene tubular membranes via thermally induced phase separation (TIPS). In this process, camphene was removed by either sublimation or extraction. The effect of the solvent-removal on the structure and properties of the resulting membrane was studied. Microscopic observation and wide angle X-ray scattering indicate that the morphology and crystalline structure difference is minor. Thermal analysis and tensile tests reveal that the crystallinity and breaking strength of the tubular membrane from the extracting method are slightly higher than those for the sublimating method. Porosity measurements show that the sublimation method can yield membranes with slightly higher porosity than the extraction method. Furthermore, permeation results indicate that membranes from extraction have a smaller permeation rate and higher retention. Therefore solvent-extraction can produce a denser membrane structure than sublimation can.     

Housing refurbishment contractors selection based on a hybrid fuzzy-QFD approach

With low demand for new construction, limited land usage, and being aware of sustainability, the refurbishment market has grown greatly and has become more in demand in the construction industry. Most refurbishment work, however, involves a high level of risk, uncertainty, and coordination, which are likely to cause asymmetric information between contractors and residents in a refurbishment process. Most private refurbishment contractor selections are usually based on word-of-mouth referrals that lack a systematic and objective assessment method. This study proposes a hybrid approach combining fuzzy set theory and quality function deployment (QFD) to establish a housing refurbishment contractor selection model. With this model, residents can select an optimal refurbishment contractor according to requirements. To test the effectiveness of the proposed model, a known multiple criteria decision-making method, PROMETHEE, is applied to compare the results of contractor selections. The result reveals that the proposed hybrid fuzzy-QFD approach can be expected to be successful and has potential for handling multiple criteria decision-making problems.     

The region of the herpes simplex virus type 1 LAT gene involved in spontaneous reactivation does not encode a functional protein

A family of muscarinic acetylcholine receptor proteins mediates diverse pre- and postsynaptic functions in the hippocampus. However the roles of individual receptors are not understood. The present study identified the pre- and postsynaptic muscarinic acetylcholine receptors at the perforant pathway synapses in rat brain using a combination of lesioning, immunocytochemistry and electron microscopic techniques. Entorhinal cortex lesions resulted in lamina-specific reductions of m2, m3, and m4 immunoreactivity in parallel with the degeneration of the medial and lateral perforant pathway terminals in the middle and outer thirds of the molecular layer, respectively. In contrast, granule cell lesions selectively reduced m1 and m3 receptors consistent with degeneration of postsynaptic dendrites. Direct visualization of m1-m4 by electron microscopic immunocytochemistry confirmed their differential pre- and postsynaptic localizations. Together, these findings provide strong evidence for both redundancy and spatial selectivity of presynaptic (m2, m3 and m4) and postsynaptic (m1 and m3) muscarinic acetylcholine receptors at the perforant pathway synapse.     

Electrochemical hydrogenation of nanocrystalline face-centered cubic Co powder

Nanocrystalline face-centered cubic (FCC) Co powder encapsulated within graphite layers was fabricated by an arc discharge method. Its electrochemical hydrogenation properties were investigated and compared with those of the hexagonal close packed (HCP) structure. Both exhibited a similar stabilized discharge capacity of approximately 350 mAh/g that can be attributed to the CoH_x/Co reaction. During the cyclic charge/discharge, transition between HCP-Co and FCC-Co took place. Graphite encapsulation was beneficial to the cycle stability of the FCC powder.     

A reference standard of defect compensation for leather transactions

Defects exist on natural leather surfaces and they usually cannot be eliminated during processing. No international criterion specifies the compensatory counting for calf leather surface defects. So complicated negotiation causes additional cost and argument between suppliers and purchasers. The objective of this article is to establish a compensatory standard of leather defects for finished leather transactions. We start by collecting 170 samples of defective leather and classify the leather defects into seven types. By using digital image processing techniques, we can identify the defects and group nearby defects into a larger scrap area. The area of leather falling into disuse can be calculated. The compensatory standard corresponding to each type of leather defect is then defined. The established compensatory standard for finished leather transactions is evaluated for simulated practical leather transaction. Simulation results showed that the proposed approach is useful and beneficial for practical leather transactions.     

Granular configurations, motions, and correlations in slow uniform flows driven by an inclined conveyor belt

The present experimental study examines the behaviour of slow granular flows, focusing on the details of particle patterns and motions over the depth of a sheared layer. A conveyor belt circuit enclosed in an inclined flume is used to generate steady uniform open-channel flows of dry granules. Particle positions near the transparent sidewall are extracted from video sequences. The Voronoï diagram is then used to characterise the configurations formed by neighbouring grains and to assist particle tracking over successive frames. This allows a qualitative visualisation of the internal structure of the flowing layer, as well as quantitative measurements of lattice defect density and granular velocities at different depths. The response of the depth profiles to different conveyor belt speeds is examined. In addition to the mean and fluctuating velocities, we probe the time and space correlations of the fluctuations.     

In situ comparison of diffusivities for hydrogen and deuterium in palladium

An electrochemical permeation method was employed to study the diffusion behaviour of hydrogen and deuterium in palladium. Solutions of 0.1 m LiOD (in D₂O) and 0.1 m LiOH (in H₂O) and their mixtures were used as the catholytes. More than one hundred diffusivity data from 20 palladium membranes were collected. Statistical analysis of these data was made to examine the validity of the reversed isotope dependence for hydrogen diffusion in palladium. It was concluded that the effective diffusivities increased with the concentration of deuterium in the electrolyte. In addition, an in situ experiment was also performed by adding to the cathodic cell an equivalent amount of LiOD solution to the original LiOH solution, or vice versa. Graphical comparison of the corresponding permeation transients showed that the permeation rate increased when deuterium was added to the solution of H₂O, and the rate decreased when hydrogen was added to the solution of D₂O. This constitutes direct evidence for the higher diffusivity of deuterium than that of hydrogen in palladium.     

The improvement of short-channel effects due to oxidation-inducedboron redistribution for counter-implantation p-MOSFET's

Delayed appearance of short-channel effects in the threshold voltage falloff has been observed for counterimplantation p-MOSFETs. The phenomenon is attributed to the oxidation-induced boron redistribution along the channel. SUPREM-3 and MINIMOS-5 and the Orlowski method were used to quantitatively characterize this behavior. Quite good agreement between simulation and experimental data were obtained. It was found that the device characteristics of submicrometer counterimplanted p-MOSFETs are improved due to the effects of boron redistribution near the channel edge