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81.
A national model of residential energy consumption requires consideration of the following end-uses: space heating, space cooling, appliances and lighting (AL), and domestic hot water (DHW). The space heating and space cooling end-use energy consumption is strongly affected by the climatic conditions and the house thermal envelope. In contrast, both AL and DHW energy consumption are primarily a function of occupant behaviour, appliance ownership, demographic conditions, and occupancy rate. Because of these characteristics, a bottom-up statistical model is a candidate for estimating AL and DHW energy consumption. This article presents the detailed methodology and results of the application of a previously developed set of neural network models, as the statistical method of the Canadian Hybrid Residential End-Use Energy and Greenhouse Gas Emissions Model (CHREM). The CHREM estimates the national AL and DHW secondary energy consumption of Canadian single-detached and double/row houses to be 248 PJ and 201 PJ, respectively. The energy consumption values translate to per household values of 27.8 GJ and 22.5 GJ, and per capita values of 9.0 GJ and 7.3 GJ, respectively. 相似文献
82.
Giovanni Forzieri Gabriele Moser Enrique R. Vivoni Fabio Castelli Francesco Canovaro 《Canadian Metallurgical Quarterly》2010,136(11):855-867
For detailed hydraulic modeling, accurate spatial information of riparian vegetation patterns needs to be derived in automatic fashion. We propose a supervised classification for heterogeneous riparian corridors with a low number of spectrally separate classes using data fusion of a Quickbird image and LIDAR data. The approach considers nine land cover classes including three woody riparian species, brush, cultivated areas, grassland, urban infrastructures, bare soil and water. The classical “stacked vector” approach is adopted for data fusion, while the nonparametric weighted feature-extraction method and the pixel-oriented maximum likelihood algorithm are used for feature-reduction and classification purposes, respectively. We test the approach over a 14-km stretch of the Sieve River (Tuscany Region, Italy). A one-dimensional river modeling is applied over the study reach comparing the results of a classification-derived hydraulic roughness map and a traditional ground-based approach. Despite the complex study reach, the classification method produced encouraging accuracies (OKS = 0.77) and represents a useful tool to delineate application domains of flow resistance models suited to different hydrodynamic patterns (e.g., stiff/flexible vegetation). Hydraulic modeling results showed that the remotely derived floodplain roughness parameterization captures the equivalent Manning coefficient over 20 test cross sections with uncertainty distributions described by low mean and standard deviation values. 相似文献
83.
84.
Compositional and structural evolution of sputtered Ti-Al-N 总被引:1,自引:0,他引:1
The compositional and structural evolution of Ti-Al-N thin films as a function of the total working gas pressure (pT), the N2-to-total pressure ratio (pN2/pT), the substrate-to-target distance (ST), the substrate position, the magnetron power current (Im), the externally applied magnetic field, and the energy and the ion-to-metal flux ratio of the ion bombardment during reactive sputtering of a Ti0.5Al0.5 target is investigated in detail. Based on this variation we propose that the different poisoning states of the Ti and Al particles of the powder-metallurgically prepared Ti0.5Al0.5 target in addition to scattering and angular losses of the sputter flux cause a significant modification in the Al/Ti ratio of the deposited thin films ranging from ~ 1.05 to 2.15.The compositional variation induces a corresponding structural modification between single-phase cubic, mixed cubic-hexagonal and single-phase hexagonal. However, the maximum Al content for single-phase cubic Ti1−xAlxN strongly depends on the deposition conditions and was obtained with x = 0.66, for the coating deposited at 500 °C, pT = 0.4 Pa, ST = 85 mm, and pN2/pT = 17%. Our results show, that in particular, the N2-to-total pressure ratio in combination with the sputtering power density of the Ti0.5Al0.5 compound target has a pronounced effect on the Al/Ti ratio and the structure development of the coatings prepared. 相似文献
85.
Integrated Sample Preparation, Reaction, and Detection on a High-frequency Centrifugal Microfluidic Platform 总被引:2,自引:0,他引:2
86.
Digital camera identification from sensor pattern noise 总被引:7,自引:0,他引:7
Lukas J. Fridrich J. Goljan M. 《Information Forensics and Security, IEEE Transactions on》2006,1(2):205-214
In this paper, we propose a new method for the problem of digital camera identification from its images based on the sensor's pattern noise. For each camera under investigation, we first determine its reference pattern noise, which serves as a unique identification fingerprint. This is achieved by averaging the noise obtained from multiple images using a denoising filter. To identify the camera from a given image, we consider the reference pattern noise as a spread-spectrum watermark, whose presence in the image is established by using a correlation detector. Experiments on approximately 320 images taken with nine consumer digital cameras are used to estimate false alarm rates and false rejection rates. Additionally, we study how the error rates change with common image processing, such as JPEG compression or gamma correction. 相似文献
87.
Vettiger P. Benedict M.K. Bona G.-L. Buchmann P. Cahoon E.C. Datwyler K. Dietrich H.-P. Moser A. Seitz H.K. Voegeli O. Webb D.J. Wolf P. 《Quantum Electronics, IEEE Journal of》1991,27(6):1319-1331
A concept for full-wafer processing (FWP) and full-wafer testing (FWT) for semiconductor laser fabrication in the AlGaAs-GaAs material system is presented. The approach is based on chemically assisted ion beam etching for the laser-mirror formation. Record values for mirror scattering, optimum mirror reflectivity, and equivalence to cleaved mirrors in terms of laser threshold and efficiency have been achieved. Promising results for uniformity and reproducibility for major laser diode characteristics on processed 2-in wafers have been found. The FWP technology has been extensively used for designing test sites to determine various materials, process, and laser parameters, such as sheet resistance, ridge dimensions, lithographic alignment errors, mirror surface leakage, etc 相似文献
88.
Intracellular H2O2 generation, as a measure of the respiratory burst, was determined after stimulation of neutrophils by immune complex (IC)-bearing human umbilical vein endothelial cells. Under static conditions, neutrophils basically responded to the immune deposits on resting endothelial cells. The rotating shear forces of approximately 0.7 dynes/cm2, corresponding to the physiological flow in postcapillary venules, completely abolished this basal H2O2 generation. After activation of the IC-bearing endothelial layers with interleukin-1 (IL-1) or tumor necrosis factor (TNF), or both, for 4 hours, rolling adhesion of the neutrophils was induced, accompanied by considerable H2O2 production. The neutrophil respiratory burst was prominently inhibited by anti-FcgammaRIII MoAb 3G8 (72.4%), and partially by MoAb 2E1 against FcgammaRII (38.5%). Both MoAbs together inhibited the Fc-mediated H2O2 generation by 93. 4%. The respiratory burst and rolling adhesion were markedly blocked by MoAb LAM1-3 against L-selectin (91.3%), whereas the nonfunctional anti-L-selectin MoAb LAM1-14 was ineffective. F(ab)2' fragments of MoAb 7A9 against E-selectin inhibited neutrophil rolling by 98.6%, but not the respiratory burst. Moreover, rolling adhesion of neutrophils and the related oxidative burst were CD11b/CD18- independent. In summary, L-selectin has a unique auxiliary function in triggering the FcgammaR-mediated respiratory burst of rolling neutrophils to IC-bearing endothelial cells, thereby substituting CD11b/CD18 under conditions of flow. 相似文献
89.
RA Memon WM Holleran AH Moser T Seki Y Uchida J Fuller JK Shigenaga C Grunfeld KR Feingold 《Canadian Metallurgical Quarterly》1998,18(8):1257-1265
Alterations in triglyceride and cholesterol metabolism often accompany inflammatory diseases and infections. We studied the effects of endotoxin (lipopolysaccharide [LPS]) and cytokines on hepatic sphingolipid synthesis, activity of serine palmitoyltransferase (SPT), the first and rate-limiting enzyme in sphingolipid synthesis, and lipoprotein sphingolipid content in Syrian hamsters. Administration of LPS induced a 2-fold increase in hepatic SPT activity. The increase in activity first occurred at 16 hours, peaked at 24 hours, and was sustained for at least 48 hours. Low doses of LPS produced maximal increases in SPT activity, with half-maximal effect seen at approximately 0.3 microg LPS/100 g body weight. LPS increased hepatic SPT mRNA levels 2-fold, suggesting that the increase in SPT activity was due to an increase in SPT mRNA. LPS treatment also produced 75% and 2.5-fold increases in hepatic sphingomyelin and ceramide synthesis, respectively. Many of the metabolic effects of LPS are mediated by cytokines. Interleukin 1 (IL-1), but not tumor necrosis factor, increased both SPT activity and mRNA levels in the liver of intact animals, whereas both IL-1 and tumor necrosis factor increased SPT mRNA levels in HepG2 cells. IL- produced a 3-fold increase in SPT mRNA in HepG2 cells, and the half-maximal dose was 2 ng/mL. IL-1 also increased the secretion of sphingolipids into the medium. Analysis of serum lipoprotein fractions demonstrated that very low density lipoprotein, intermediate density lipoprotein, and low density lipoprotein isolated from animals treated with LPS contained significantly higher amounts of ceramide, glucosylceramide, and sphingomyelin. Taken together, these results indicate that LPS and cytokines stimulate hepatic sphingolipid synthesis, which results in an altered structure of circulating lipoproteins and may promote atherogenesis. 相似文献
90.
M Moser 《Canadian Metallurgical Quarterly》1998,279(22):1813-1816
Diuretics have again been recommended by the Sixth Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC VI) as one of the first-choice medications in the management of hypertension. This recommendation is based on the results of numerous randomized, diuretic-based, long-term controlled clinical trials that have demonstrated a reduction in both cerebrovascular and cardiovascular morbidity. Despite this and other national recommendations, the use of diuretics has steadily decreased over the past 15 years. Reasons include heavy promotion of other medications and the perception that diuretics produce adverse metabolic effects and do not reduce coronary heart disease events. Data, however, indicate that (1) changes in glucose and cholesterol metabolism are minor, especially with the smaller doses now being used; (2) cardiovascular morbidity and mortality have been reduced in hypertensive patients, even in those with hyperlipidemia or diabetes, when diuretics are used; and (3) concerns about hypokalemia-induced arrhythmias have been overstated. While special indications exist for other medications in the treatment of hypertension, for example, use of an angiotensin-converting enzyme inhibitor (usually in addition to a diuretic) for a patient with heart failure or diabetic nephropathy, most patients, including those with hyperlipidemia or glucose intolerance, can be effectively treated with a diuretic as initial therapy or as part of a combination regimen. Diuretics should be used more not less frequently; use of diuretics would reduce the number of resistant hypertensive patients. 相似文献