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1.

Bursts of drinking water pipes not only cause loss of drinking water, but also damage below and above ground infrastructure. Short-term water demand forecasting is a valuable tool in burst detection, as deviations between the forecast and actual water demand may indicate a new burst. Many of burst detection methods struggle with false positives due to non-seasonal water consumption as a result of e.g. environmental, economic or demographic exogenous influences, such as weather, holidays, festivities or pandemics. Finding a robust alternative that reduces the false positive rate of burst detection and does not rely on data from exogenous processes is essential. We present such a burst detection method, based on Bayesian ridge regression and Random Sample Consensus. Our exogenous nowcasting method relies on signals of all nearby flow and pressure sensors in the distribution net with the aim to reduce the false positive rate. The method requires neither data of exogenous processes, nor extensive historical data, but only requires one week of historical data per flow/pressure sensor. The exogenous nowcasting method is compared with a common water demand forecasting method for burst detection and shows sufficiently higher Nash-Sutcliffe model efficiencies of 82.7% - 90.6% compared to 57.9% - 77.7%, respectively. These efficiency ranges indicate a more accurate water demand prediction, resulting in more precise burst detection.

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Feeding difficulty and malnutrition are common in disabled children. Intake may be reduced because of anorexia, chewing and swallowing difficulties, or vomiting. Feeding is often time consuming, unpleasant, and may result in aspiration. Malnutrition may result in impaired growth and neurodevelopment, and impaired cardiorespiratory, gastrointestinal, and immune functions. Multidisciplinary assessment is recommended and should include a feeding history, oral-motor examination, and nutritional assessment. The energy requirements of most disabled children are less than those for a normal child of the same age but may be increased by spasticity, athetosis, convulsions, and recurrent infections. Micronutrient deficiencies may occur even in children receiving nutritionally complete feeds if the volume is reduced because of low energy requirements. Oral intake may be improved by a change of posture, special seating, feeding equipment, oral desensitization, mashing or pureeing of lumpy food, thickening of liquids, use of calorie supplements, and treatment of reflux/esophagitis. Non-oral feeding should be considered when oral feeding is unsafe, not enjoyable, inadequate, or very time consuming. Long-term support requires a gastrostomy. This is less obtrusive than a nasogastric tube, less likely to become displaced, less traumatic, and is associated with improved quality of life, but is also associated with significant morbidity. If there is symptomatic reflux a fundoplication may be required, but this is associated with significant mortality and substantial morbidity.  相似文献   
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The half-life of 60Fe has been measured to be T12 = (1.49 ± 0.27) × 106 a, significantly longer than the one previous measurement of Roy and Kohman which reported a value of 3 × 105 a uncertain by a factor of 3. The present value was obtained from measurements of specific activity and radioisotope concentration in a material produced by spallation of copper with 191 MeV protons. 60Fe/Fe ratios in the range of 10?8 were measured with the Argonne FN tandem-superconducting linear accelerator system in conjunction with an Enge split-pole spectrograph. The specific activity of 60Fe in Fe was measured through the grow-in of the 1.332 MeV gamma-ray line of the 60Co daughter activity.  相似文献   
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Water Resources Management - The increasing age and deterioration of drinking water mains is causing an increasing frequency of pipe bursts. Not only are pipe repairs costly, bursts might also lead...  相似文献   
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In this research, ultrasonic pulse echo measurements are used to quantify through thickness chemical degradation in thin mortar specimens. The degradation level is predicted using the time of travel of the acoustic wave through the thickness of the structure. The front and back wall interaction reflections are used to obtain additional information from very early stage degradation. The pulse-velocity of sound waves as a function of the thickness of the layers within the structure is described. With knowledge of the pulse-velocity in pristine and fully degraded conditions, it is possible to determine the complete range of degradation length over the layer thickness. The method is applicable for leaching of calcium and acidic attack. The acoustic measurements were verified with destructive testing. The correlation between the acoustic and non-acoustic experiments agree with the described pulse-velocity and degraded depth function. The method based on ultrasonic measurements can be implemented in other thin-layered structures.  相似文献   
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A substantial proportion of subjects with autosomal recessive retinitis pigmentosa (arRP) or Usher syndrome type II (USH2) lacks a genetic diagnosis due to incomplete USH2A screening in the early days of genetic testing. These cases lack eligibility for optimal genetic counseling and future therapy. USH2A defects are the most frequent cause of USH2 and are also causative in individuals with arRP. Therefore, USH2A is an important target for genetic screening. The aim of this study was to assess unscreened or incompletely screened and unexplained USH2 and arRP cases for (likely) pathogenic USH2A variants. Molecular inversion probe (MIP)-based sequencing was performed for the USH2A exons and their flanking regions, as well as published deep-intronic variants. This was done to identify single nucleotide variants (SNVs) and copy number variants (CNVs) in 29 unscreened or partially pre-screened USH2 and 11 partially pre-screened arRP subjects. In 29 out of these 40 cases, two (likely) pathogenic variants were successfully identified. Four of the identified SNVs and one CNV were novel. One previously identified synonymous variant was demonstrated to affect pre-mRNA splicing. In conclusion, genetic diagnoses were obtained for a majority of cases, which confirms that MIP-based sequencing is an effective screening tool for USH2A. Seven unexplained cases were selected for future analysis with whole genome sequencing.  相似文献   
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Strong electric fields for disinfection of wastewaters have been employed already for several decades. An innovative approach combining low strength (7 V/cm) alternating electric fields with a granular activated carbon fluidized bed electrode (FBE) for disinfection was presented recently. For disinfection performance of FBE several pure microbial cultures were tested: Bacillus subtilis, Bacillus subtilis subsp. subtilis, Enterococcus faecalis as representatives from Gram positive bacteria and Erwinia carotovora, Pseudomonas luteola, Pseudomonas fluorescens and Escherichia coli YMc10 as representatives from Gram negative bacteria. The alternating electric field amplitude and shape were kept constant. Only the effect of alternating electric field frequency on disinfection performance was investigated. From the bacteria tested, the Gram negative strains were more susceptible and the Gram positive microorganisms were more resistant to FBE disinfection. The collected data indicate that the efficiency of disinfection is frequency and strain dependent. During 6 h of disinfection, the decrease above 2 Log units was achieved with P. luteola and E. coli at 10 kHz and at dual frequency shift keying (FSK) modulated signal with frequencies of 10 kHz and 140 kHz. FBE technology appears to offer a new way for selective bacterial disinfection, however further optimizations are needed on treatment duration, and energy input, to improve effectiveness.  相似文献   
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Neutral Cs vapor flowing onto the sputter target in an inverted negative ion Cs sputter source has been used to enhance the intensity of the negative ion beam.  相似文献   
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A novel device called the Bioscope System is investigated for feasibility as sensor for chemicals in aqueous solutions. Thereby a sample is examined by a pulsed voltage and electrical properties of that sample are measured. These electrical properties can be considered as a sum parameter of the sample in terms of conductivity and permittivity. It is demonstrated that the Bioscope System can indeed measure differences between different substances in aqueous solution and between different concentrations of the same substance in aqueous solution. A qualitative explanation is provided. Possible improvements of the system are suggested.  相似文献   
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