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1.
A model-based method for fault detection in tapping based on torque and radial forces is proposed. The method allows the identification of faults typical of a tapping operation including axial misalignment, tap runout, tooth breakage both singly and together. The validation experiments have been run on aluminum 356 workpieces for different combinations of process faults. Results have shown that the model predictions are in good agreement with the experimental radial force and torque signals under various fault conditions.  相似文献   
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In recent years, an increasing need has arisen for various types of construction on sites underlain by soft cohesive soils. In such cases, some methods of soil improvement are usually required to provide adequate bearing capacity and tolerable postconstruction total and differential settlements. These goals often may be achieved by precompression or preloading the site prior to construction. Precompression and preloading are frequently used in combination with vertical drains, especially in very thick soft deposits, otherwise the time required for consolidation may be unacceptably long or the instability of the foundation may be a serious concern. Therefore, the vertical geocomposite (jute and coir) drain may be used to accelerate the settlement of soil thereby making the site available for use in the shortest time. The computer program and the design chart for determining the spacing between geocomposite drains are presented. This technique is generally useful for embankment construction, tank foundation, underwater construction and landfill areas. Two projects (Haldia in West Bengal and Vashi Station Complex in Bombay) have utilized the application of geocomposite drains reported in this paper.  相似文献   
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Wireless Personal Communications - Scheduling in computing environments such as homogeneous and heterogonous is very challenging and faces various difficulties computationally. This computing needs...  相似文献   
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The solar chimney is a passive solar system which can be used for enhance the natural ventilation and space conditioning of a building. A solar chimney design is modified and installed at CBRI Roorkee (29.87° N 77.88° E), India. A Computational fluid dynamics (CFD) software is used for prediction of velocity and temperature in Modified solar chimney (MSC) and evaluating the Air Change per hour (ACH), which is validated through experimental and theoretical counterpart and found a good agreement between them. From the result of thermal performance analysis, it is found that MSC generates 2.39–7.13 ACH in experimental room in month of May 2013, when outdoor solar radiation was in the range of 250–612 W/m2. Due to this ACH, the room temperature is dropped by 2–4°C as compared to reference room temperature. The parametric study shows that the optimum glass tilt angle estimated by 5 degree for highest performance consideration of MSC. The air gap is optimised by 60 mm and air gap to inlet opening height ratio is optimised by 0.2.  相似文献   
7.
Colloidal silver is observed to affect the transmittance of p-type Cd1−y Zn y Te (CZT) single-crystal substrate material at room temperature. The optical transmittance spectra have been analyzed in the near-infrared (NIR) and mid-infrared (MIR) regions. The transmittance characteristics of CZT showed significant reduction in absorption due to split-off valance band transitions in the NIR region and intervalence band absorption in the MIR region upon coating CZT substrates with silver paste. This reduction in absorption has been explained to be due to the compensation of the acceptor defects (native and foreign). Silver atoms incorporated from the silver coating help in compensation of these defects. A similar effect on transmittance characteristics of mercury cadmium telluride (MCT) epilayers grown on CZT substrates after coating silver paste on the CZT substrate side was also observed. An improvement in the transmittance of CZT substrates after the application of silver paste was observed. A similar improvement in transmittance is usually achieved by annealing the substrates in a Cd/Zn atmosphere. The results are explained by considering the formation of neutral complexes of acceptors (cadmium vacancies) and the interstitial silver. This study also points to the important conclusion that silver paste on CZT should be applied with caution for measurement purposes since it diffuses even at room temperature and modifies the optical characteristics.  相似文献   
8.
The nanopatterning of crystalline ZnS thin film surfaces under 80 keV Ar+ ions irradiation at incident angles of 0°, 20°, and 40° is presented. Structural and morphological changes have been investigated by means of X-ray diffraction and atomic force microscopy respectively. The surface morphology mainly consists of nanograins of spherical shape in pristine and films irradiated at normal incidence. The irradiation at oblique angle (20° and 40°) leads to the formation of ripple structures on the surface with a wave vector parallel to the ion beam direction. The existing theories for the ripple formation are invoked to explain the observed surface structure.  相似文献   
9.
BACKGROUND: Tea is the most consumed beverage worldwide after water. Yet very little is known about the genetics of tea in comparison with other crop species. Here we have taken advantage of the polymorphic nature of microsatellite DNA to investigate the mode of chloroplast inheritance in tea, Camellia sinensis (L.) O. Kuntze. This is important for the correct interpretation of phylogeny and introgression data as well as assessing the suitability of chloroplast transformation as a means for transgene containment in tea. RESULTS: The study was based on six Japanese tea cultivars, namely Aj2, CK23, Hatsumomiji, Nka05, Yamanoibuki and Kanayamidori used to generate four informative families. The parental pairs in the crosses differed at a single chlroroplast locus with respect to an imperfect microsatellite repeat of 16 nucleotide bases. In agreement with earlier cytological studies, all 61 progeny displayed a cpDNA profile that was consistent with the maternal inheritance of chloroplasts in tea. CONCLUSIONS: The data generated here provide the first molecular evidence of the plastid inheritance in tea. However, we suggest that additional families and polymorphic markers be screened for increasing the confidence in the observed maternal inheritance of chloroplasts in this important crop species. Copyright © 2011 Society of Chemical Industry  相似文献   
10.
Shiv Kumar  G.N. Tiwari 《Solar Energy》2009,83(9):1656-110
In this paper, an attempt is made to estimate the internal heat transfer coefficients of a deep basin hybrid (PV/T) active solar still. The estimation is based on outdoor experimental observation of hybrid (PV/T) solar still for composite climate of New Delhi (latitude 28°35′N and longitude 77°12′E). The internal heat transfer coefficients are evaluated by using thermal models proposed by various researchers. The comparison of hourly yield predicted using various thermal models to the experimental has also been carried out by evaluating the correlation coefficient and percentage deviation. It is observed that, Kumar and Tiwari model (KTM) better validate the results than the others model. The average annual values of convective heat transfer coefficient for the passive and hybrid (PV/T) active solar still are observed as 0.78 and 2.41 W m−2 K−1, respectively at 0.05 m water depth.  相似文献   
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