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971.
Industrial control systems (ICS), such as smart grid systems, are frequently composed of hundreds of devices distributed over a large geographic area. While mobile applications have been used with good success in managing ICSs, traditional methods of distributing applications (e.g., app stores) are not well suited to the task of discovering, distributing, and building human machine interfaces (HMIs) for ICS, as the highly individualized and often proprietary individual components of ICSs have vastly different interfaces leading to a need to download hundreds of applications. We propose the No Effort Rapid Development (NERD) middleware framework to address the challenges of in-field HMI discovery, provisioning, communication, and co-evolution with related ICSs. Middleware services offer the ability to simplify on-demand HMI distribution and operation of ICSs. NERD leverages existing ICS device-markers (e.g., QR-codes or RFID tags) or Bluetooth low-energy protocols for rapid cyber-physical discovery and provisioning of HMIs in the field. Device-markers and Bluetooth low-energy protocols have a very limited data capacity and transmission speed, and to achieve on-device storage of HMIs, we propose using a compact data-driven domain-specific language that emphasizes data sources and sinks between the HMI and IC. 相似文献
972.
White PJ Clement GT 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2007,54(11):2309-2317
Traditional ultrasound imaging methods rely on the bandwidth and center frequency of transduction to achieve axial and radial image resolution, respectively. In this study, a new modality for spatially localizing scattering targets in a two-dimensional field is presented. In this method, the bandwidth of field excitation is high, and the center frequency is lowered such that the corresponding wavelengths are substantially larger than the target profiles. Furthermore, full two-dimensional field measurements are obtained with single send-receive sequences, demonstrating a substantial simplification of the traditional scanning techniques. Field reconstruction is based on temporal-spectral cross-correlations between measured backscatter data and a library of region of interest (ROI) backscatter data measured a priori. The transducer design is based upon a wedge-shaped geometry, which was shown to yield spatially frequency-separated bandwidths of up to 156% with center frequencies of 1.38 MHz. Initial results with these send-and-receive transducer parameters and cylindrical reflection targets in a 10-mm x 10-mm ROI demonstrate two-dimensional target localization to within 0.5 mm. Spatial localization of point scatterers is demonstrated for single and multiple scattering sites. 相似文献
973.
Pustovrh MC Jawerbaum A White V Capobianco E Higa R Martínez N López-Costa JJ González E 《Reproduction (Cambridge, England)》2007,134(4):605-613
Matrix metalloproteinases (MMPs) play an important role in tissue remodeling that accompanies the rapid growth, differentiation, and structural changes of the placenta and several fetal organs. In the present study, we investigated whether the diabetic maternal environment may alter the regulatory homeostasis exerted by nitric oxide (NO) on MMPs activity in the feto-placental unit from rats at midgestation. We found that NADPH-diaphorase activity, which reflects the distribution and activity of NO synthases (NOS), was increased in both placenta and fetuses from diabetic rats when compared with controls. In addition, while a NO donor enhanced MMP2 and MMP9 activities, a NOS inhibitor reduced these activities in the maternal side of the placenta from control rats. This regulatory effect of NO was only observed on MMP9 in the diabetic group. On the other hand, the NO donor did not modify MMP2 and MMP9 activities, while the NOS inhibitor reduced MMP9 activity in the fetal side of both control and diabetic placentas. In the fetuses, MMP2 was enhanced by the NO donor and reduced by the NO inhibitor in both fetuses from control and diabetic rats. Overall, this study demonstrates that NO is able to modulate the activation of MMPs in the feto-placental unit, and provides supportive evidence that increased NOS activity leads to NO overproduction in the feto-placental unit from diabetic rats, an alteration closely related to the observed MMPs dysregulation that may have profound implications in the formation and function of the placenta and the fetal organs. 相似文献
974.
Jose A. Gerde Connie L. Hardy Charles R. HurburghJr Pamela J. White 《Journal of the American Oil Chemists' Society》2007,84(6):519-522
Measures of free fatty acids (FFA), total polar materials (TPM), and conjugated dienoic acids (CDA), typical indices of oil
degradation, were analyzed in daily oil aliquots taken from soybean oils with different linolenic acid concentrations used
to fry French fries. The oils also were scanned with a reflectance near-infrared spectrometer using a wavelength range of
350–2,500 nm. By using partial least squares and one-out cross validation, calibrations were developed to quantitatively determine
FFA, TPM, and CDA by near-infrared spectroscopy (NIRS). The coefficients of determination (R
2) when compared to the standard methods were 0.973 for FFA, 0.984 for TPM, and 0.902 for CDA. NIRS was an accurate and fast
method to determine FFA, TPM, and CDA in oxidized oils. The ability to obtain different parameters simultaneously makes NIRS
a potentially valuable tool for food quality assurance. 相似文献
975.
The observation of single sheets of graphite (graphene) presents new possibilities for carbon-based nanoelectronics. We report defect tolerant configurations for a nearly reflectionless 120 degrees turn and nearly reflectionless symmetric and asymmetric splitters, which can be cut from graphene. Connections between zigzag strips of different widths can be made with either low or high reflectance depending on the connection shape. 相似文献
976.
In equilibrium, graphene nanostrips, with hydrogens sp2-bonded to carbons along their zigzag edges, are expected to exhibit a spin-polarized ground state. However, in the presence of a ballistic current, we find that there exists a voltage range over which both spin-polarized and spin-unpolarized nanostrip states are stable. These states can represent a bit in a binary memory device that could be switched through the applied bias and read by measuring the current through the nanostrip. 相似文献
977.
978.
DM Cummings L Whetstone D White C Nelson J Morgan D Poole J Morrow 《Canadian Metallurgical Quarterly》1999,60(1):26-28
Most patients with chronic renal failure who are on maintenance hemodialysis are anovulatory and have menstrual abnormalities. This study was designed to determine the prevalence of organic causes of abnormal uterine bleeding in this group of patients exposed to unopposed estrogens. Eighteen patients with chronic renal failure and abnormal uterine bleeding underwent vacuum curettage. The histopathologic findings were compared with a group of 154 premenopausal women who had abnormal uterine bleeding without detectable organic causes. Excluding patients with secretory and atrophic endometrium, only 2 of 8 patients (25%) with chronic renal failure had endometrial lesions while 44 of 131 patients (33.6%) had either endometrial polyp, simple or atypical endometrial hyperplasia or endometrial carcinoma (p > 0.05). The uremic environment caused by chronic renal failure does not alter the endometrial responsiveness to unopposed estrogens and may lead to the development of endometrial lesions. 相似文献
979.
Sex ratio after exposure to dioxin-like chemicals in Taiwan 总被引:1,自引:0,他引:1
980.
JJ Plomp PC Molenaar GM O'Hanlon BC Jacobs J Veitch MR Daha PA van Doorn FG van der Meché A Vincent BP Morgan HJ Willison 《Canadian Metallurgical Quarterly》1999,45(2):189-199
In the Miller Fisher syndrome (MFS) variant of the Guillain-Barré syndrome, weakness is restricted to extraocular muscles and occasionally other craniobulbar muscles. Most MFS patients have serum antibodies against ganglioside type GQ1b of which the pathophysiological relevance is unclear. We examined the in vitro effects of MFS sera, MFS IgG, and a human monoclonal anti-GQ1b IgM antibody on mouse neuromuscular junctions (NMJs). It was found that anti-GQ1b antibodies bind at NMJs where they induce massive quantal release of acetylcholine from nerve terminals and eventually block neuromuscular transmission. This effect closely resembled the effect of the paralytic neurotoxin alpha-latrotoxin at the mouse NMJs, implying possible involvement of alpha-latrotoxin receptors or associated downstream pathways. By using complement-deficient sera, the effect of anti-GQ1b antibodies on NMJs was shown to be entirely dependent on activation of complement components. However, neither classical pathway activation nor the formation of membrane attack complex was required, indicating the effects could be due to involvement of the alternative pathway and intermediate complement cascade products. Our findings strongly suggest that anti-GQ1b antibodies in conjunction with activated complement components are the principal pathophysiological mediators of motor symptoms in MFS and that the NMJ is an important site of their action. 相似文献