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排序方式: 共有846条查询结果,搜索用时 46 毫秒
51.
52.
Consider a heteroscedastic regression model Y=m(X)+σ(X)ε, where m(X)=E(Y|X) and σ
2(X)=Var (Y|X) are unknown, and the error ε is independent of the covariate X. We propose a new type of test statistic for testing whether the regression curve m(⋅) belongs to some parametric family of regression functions. The proposed test statistic measures the distance between the
empirical distribution function of the parametric and of the nonparametric residuals. The asymptotic theory of the proposed
test is developed, and the proposed testing procedure is illustrated by means of a small simulation study and the analysis
of a data set. 相似文献
53.
Junfeng Fan Kazuo Sakiyama Ingrid Verbauwhede 《Design Automation for Embedded Systems》2008,12(3):231-242
The increasing use of network-connected embedded devices and online transactions creates a growing demand of network security
for embedded systems. The security requirements, such as authentication, confidentiality and integrity, always make computationally
intensive processes and can easily become the bottleneck of the related applications. In this paper we implement Elliptic
Curve Cryptography (ECC) (Miller in Lecture Notes in Computer Science, vol. 218, pp. 417–426, 1985; Koblitz in Math. Comput. 48:203–209, 1987) on an embedded multicore system, and explore the task scheduling methods in different levels. First, we propose an instruction
scheduling method that utilizes all the cores to perform one modular operation in parallel. Second, we perform multiple modular
operations with multiple cores in parallel. The performance of those two implementations is compared and a scheduling method
combining these two types of parallelism is proposed. We discuss the details of our proposed method by using an FPGA implementation
of ECC over a prime field. 相似文献
54.
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56.
Franz Ferdinand Reinthaler Gebhard Feierl Herbert Galler Doris Haas Eva Leitner Franz Mascher Angelika Melkes Josefa Posch Ingrid Winter Gernot Zarfel Egon Marth 《Water research》2010,44(6):1981-1985
The aim of this study was to investigate the degree of contamination of sewage sludge with ESBL-producing Escherichia coli strains and the effectiveness of different sewage sludge treatment methods.Monthly sewage sludge samples were collected between January and September 2009 in 5 different sewage treatment plants and tested for the presence of ESBL E. coli. In addition, the number of colony forming units (CFU) of E. coli and coliform bacteria before and after the different sludge treatment methods (aerobic/anaerobic digestion, lime stabilization, and thermal treatment) was investigated.Of the 72 sewage sludge samples investigated, ESBL-positive E. coli were found in 44 (61.1%) sewage sludge samples. The classification of β-lactamase groups was carried out in 15 strains resulting in the detection of 2 different groups (CTX-M and TEM) of bla genes. All 15 of them had a CTX-M gene and 4 of these strains furthermore carried a TEM gene.With regard to the CFU of E. coli and coliform bacteria, thermal treatment and lime stabilization following dehydration sufficiently reduced pathogen concentrations. The plants using merely stabilization and dehydration showed an increase of E. coli and coliform bacteria and thus also an increase in ESBL-producing E. coli. 相似文献
57.
The purpose of this study was to analyze the diagnostic capacity of different classification criteria based on Body Mass Index in the assessment of nutritional status and to evaluate their effectiveness. The sample comprised 367 healthy pregnant adolescents in their first trimester of gestation, from a socioeconomic level IV, between Oct. 1999 and Dec. 2008. Two methodologies were applied for the nutritional classification: (1) Integral nutritional diagnosis (gold standard), and (2) Body Mass Index (BMI), using local reference values: Proyecto Venezuela and the Transversal Study of Caracas, and international reference values: Frisancho and WHO 2006. Concordances, kappa, sensitivity, specificity, positive and negative predictive values, positive and negative likelihood ratios, and the Youden index were calculated. According to the gold standard and BMI, the percentage of well-nourished pregnant women ranged between 62.4% and 80.6%. Within the deficit range, Frisancho was the most effective with kappa: 0.80; sensitivity: 87.3%; specificity: 94.8%; positive likelihood ratio: 16.9, and negative likelihood ratio: 0.13; Youden index: 0.82. Within the excess range, Frisancho and the Transversal Study of Caracas were the most effective with Youden index: 0.86 and 0.83, respectively. These results revealed that Frisancho was the best criterion to diagnose malnutrition in deficit in pregnant women. All references have an adequate diagnostic capacity for the excess range, of which Frisancho and the Transversal Study of Caracas are the best. We recommend using such reference values to optimize the efficiency of the BMI indicator in diagnosing malnutrition in deficit and in excess in the first trimester of gestation in pregnant adolescents within populations with similar characteristics. 相似文献
58.
Karin Datzberger Ingrid Steiner Josef Washüttl Gerhard Kroyer 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1992,194(6):524-526
Summary Zweigelt 1987, a typical Austrian wine treated with wine additives such as sulphur dioxide,l-ascorbic acid and sorbic acid was stored for 77 days. All characteristic wine components were analysed during the storage period. Only changes in colour could be detected. The changes in the amount of anthocyanins and anthocyanidin chlorides were analysed. The results show that Zweigelt 1987 mixed with wine additives such asl-ascorbic acid or sorbic acid resulted in a larger loss in colour than untreated wine. The changes could be measured photometrically but they were invisible to the naked eye. Appropriate use of wine additives did not appear to deterioriate the ruby colour of young red wine during the period tested.
Der Einfluß von Wein-Zusatzstoffen auf Farbe und Farbqualität von jungem Rotwein
Zusammenfassung Österreichischer Wein Zweigelt 1987, welcher für die Versuchsreihe unter authentischen Bedingungen hergestellt worden war, wurde mit Weinbehandlungsmitteln wie Schwefeldioxid, Sorbinsäure undl-Ascorbinsäure versetzt. Die Wechselwirkungen der Farbe des Rotweines mit den zugesetzten Chemikalien wurden während einer Lagerzeit von 77 Tagen studiert. Die Anthocyane und Anthocyanidinchloridmengen wurden bestimmt. Die Ergebnisse zeigen, daß Zweigelt 1987, der mitl-Ascorbinsäure bzw. Sorbinsäure versetzt worden war, etwas größere Farbverluste zeigte als unbehandelter Wein. Abschließend wurde festgestellt, daß die Farbveränderungen zwar photometrisch meßbar sind, aber mit freiem Auge nicht erkannt werden. Eine Verwendung dieser Weinbehandlungsmittel in richtiger Dosierung führt zu keiner Verschlechterung der Farbqualität bei jungem Rotwein über den untersuchten Zeitraum.相似文献
59.
Hervais-Adelman Alexis; Davis Matthew H.; Johnsrude Ingrid S.; Carlyon Robert P. 《Canadian Metallurgical Quarterly》2008,34(2):460
Speech comprehension is resistant to acoustic distortion in the input, reflecting listeners' ability to adjust perceptual processes to match the speech input. This adjustment is reflected in improved comprehension of distorted speech with experience. For noise vocoding, a manipulation that removes spectral detail from speech, listeners' word report showed a significantly greater improvement over trials for listeners that heard clear speech presentations before rather than after hearing distorted speech (clear-then-distorted compared with distorted-then-clear feedback, in Experiment 1). This perceptual learning generalized to untrained words suggesting a sublexical locus for learning and was equivalent for word and nonword training stimuli (Experiment 2). These findings point to the crucial involvement of phonological short-term memory and top-down processes in the perceptual learning of noise-vocoded speech. Similar processes may facilitate comprehension of speech in an unfamiliar accent or following cochlear implantation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
Ingrid M le Roux Karl le Roux W Scott Comulada Erin M Greco Katherine A Desmond Nokwanele Mbewu Mary Jane Rotheram-Borus 《Nutrition journal》2010,9(1):56