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51.
Jack A. Stone Mohamed Amer Bryon Faust Jay Zimmerman 《Journal of research of the National Institute of Standards and Technology》2004,109(3):319-333
We have studied a number of effects that can give rise to errors in small-angle measurement systems when they are used to calibrate artifacts such as optical polygons. Of these sources of uncertainty, the most difficult to quantify are errors associated with the measurement of imperfect, non-flat faces of the artifact, causing the instrument to misinterpret the average orientation of the surface. In an attempt to shed some light on these errors, we have compared autocollimator measurements to angle measurements made with a Fizeau phase-shifting interferometer. These two instruments have very different operating principles and implement different definitions of the orientation of a surface, but (surprisingly) we have not yet seen any clear differences between results obtained with the autocollimator and with the interferometer. The interferometer is in some respects an attractive alternative to an autocollimator for small-angle measurement; it implements an unambiguous and robust definition of surface orientation in terms of the tilt of a best-fit plane, and it is easier to quantify likely errors of the interferometer measurements than to evaluate autocollimator uncertainty. 相似文献
52.
H. A. Amer M. F. Sedik F. A. Khalafalla Hoda Abd El-Ghany Awad 《Molecular nutrition & food research》1991,35(2):133-138
The main muscle constituents in 100 male and female prawn as related to their moisture contents were analysed. The study was aimed to assess the nutritional state in which prawn exists and determine which sex is the more susceptible to changes. Significant higher levels of ash and water in males and relatively greater contents of fat, protein, carbohydrates, phosphorus and gross energy in females were determined. The data given in this study can establish the non starved condition in which the prawn exist. The variation in muscle constituents between male and female prawn reflects the differences in the sex development and their energy requirements during maturation. 相似文献
53.
We present a new model for testing real-time protocols with multiple timers, which captures complex timing dependencies by using simple linear expressions involving timer-related variables. This new modeling technique, combined with the algorithms to eliminate inconsistencies, allows generation of feasible test sequences without compromising their fault coverage. The model is specifically designed for testing to avoid performing full reachability analysis, and to control the growth of the number of test scenarios. Based on extended finite state machines, it is applicable to languages such as SDL, VHDL, and Estelle. The technique models a realistic testing framework in which each I/O exchange takes a certain time to realize and timers can be arbitrarily started or stopped. A software tool implementing this technique is used to generate test cases for the US Army wireless standard MIL-STD 188-220. 相似文献
54.
A. A. Fadda H. A. Etman F. A. Amer M. Barghout Kh. S. Mohamed 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1995,62(2):165-169
Ten variously substituted derivatives ( IIa–j ) of 3′-(benzimidazol-2-yl)-4′-hydroxyazobenzene were prepared. The effects of the nature and orientation of the substituents on the colour and dyeing properties of these dyes on polyester and acrylic fibres were evaluated. 相似文献
55.
Pyrimidine‐5‐carboxylate derivative Ia was utilised as a key intermediate for the synthesis of new pyrimidine derivatives. Thiopyrimidine derivative Ia undergo N‐methylation using methyl iodide afforded III. Methylsulfanyl moiety in II was easily removed when reacted with phenyl hydrazine and thiosemicarbazide afforded pyrimidine derivatives IV and VI, respectively. The reaction on nitrogen atom in Ia using 1,3‐dibromo‐propane, benzoyl chloride, phosphorous oxychloride afforded VIII, IX and X, respectively. The reaction using 1,3‐dibromo‐propane or 1,2‐dibromo‐ethane furnished the formation of the corresponding fused cycles containing sulfur. Representative compounds of the synthesised products were evaluated as antioxidant and corrosion inhibitors for gasoline lube oils. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
56.
Twenty Holstein cows were used in a randomized complete block experiment to determine the feeding value of pearl millet silage (MS) for dairy cows relative to corn silage (CS). Two isonitrogenous diets were formulated with a 53:47 forage:concentrate ratio. Pearl millet silage and CS comprised 67% of the forages in each diet. Relative to CS, MS contained higher crude protein (13.0 vs. 9.4%), neutral detergent fiber (66.9 vs. 40.7%), and acid detergent fiber (38.8 vs. 23.9%). Dietary treatments had no effect on dry matter (average = 23.9 kg/d) or crude protein (average = 4.2 kg/d) intake. However, cows fed MS consumed more neutral detergent fiber (9.7 vs. 8.3 kg/d) than did cows fed CS. Silage type had no effect on milk yield (average 38.0 kg/d), whereas energy-corrected milk (43.8 vs. 38.6) and 4% fat-corrected milk (41.8 vs. 35.5 kg/d) were greater for cows fed MS than for those fed CS. Milk protein, lactose, and total solids concentrations were not influenced by dietary treatments. However, cows fed MS produced milk with a greater milk fat concentration (4.17 vs. 3.78%) than did cows fed CS. We concluded that MS, when compared with CS, had a similar effect on feed intake, milk yield, and milk efficiency. Because of increased milk fat concentration, cows fed MS produced more energy-corrected milk than did cows fed CS. 相似文献
57.
Most global motion estimation (GME) methods are oriented to video coding while video object segmentation methods either assume no global motion (GM) or directly adopt a coding-oriented method to compensate for GM. This paper proposes a hierarchical differential GME method oriented to video object segmentation. A scheme which combines three-step search and motion parameters prediction is proposed for initial estimation to increase efficiency. A robust estimator that uses object information to reject outliers introduced by local motion is also proposed. For the first frame, when the object information is unavailable, a robust estimator is proposed which rejects outliers by examining their distribution in local neighborhoods of the error between the current and the motion-compensated previous frame. Subjective and objective results show that the proposed method is more robust, more oriented to video object segmentation, and faster than the referenced methods. 相似文献
58.
In this paper, we considered the Length-biased weighted Lomax distribution and constructed new acceptance sampling plans (ASPs) where the life test is assumed to be truncated at a pre-assigned time. For the new suggested ASPs, the tables of the minimum samples sizes needed to assert a specific mean life of the test units are obtained. In addition, the values of the corresponding operating characteristic function and the associated producer’s risks are calculated. Analyses of two real data sets are presented to investigate the applicability of the proposed acceptance sampling plans; one data set contains the first failure of 20 small electric carts, and the other data set contains the failure times of the air conditioning system of an airplane. Comparisons are made between the proposed acceptance sampling plans and some existing acceptance sampling plans considered in this study based on the minimum sample sizes. It is observed that the samples sizes based on the proposed acceptance sampling plans are less than their competitors considered in this study. The suggested acceptance sampling plans are recommended for practitioners in the field. 相似文献
59.
Mohamed R. Amer Timothy Shields Behjat Siddiquie Amir Tamrakar Ajay Divakaran Sek Chai 《International Journal of Computer Vision》2018,126(2-4):440-456
We propose a novel hybrid model that exploits the strength of discriminative classifiers along with the representation power of generative models. Our focus is on detecting multimodal events in time varying sequences as well as generating missing data in any of the modalities. Discriminative classifiers have been shown to achieve higher performances than the corresponding generative likelihood-based classifiers. On the other hand, generative models learn a rich informative space which allows for data generation and joint feature representation that discriminative models lack. We propose a new model that jointly optimizes the representation space using a hybrid energy function. We employ a Restricted Boltzmann Machines (RBMs) based model to learn a shared representation across multiple modalities with time varying data. The Conditional RBMs (CRBMs) is an extension of the RBM model that takes into account short term temporal phenomena. The hybrid model involves augmenting CRBMs with a discriminative component for classification. For these purposes we propose a novel Multimodal Discriminative CRBMs (MMDCRBMs) model. First, we train the MMDCRBMs model using labeled data by training each modality, followed by training a fusion layer. Second, we exploit the generative capability of MMDCRBMs to activate the trained model so as to generate the lower-level data corresponding to the specific label that closely matches the actual input data. We evaluate our approach on ChaLearn dataset, audio-mocap, as well as the Tower Game dataset, mocap-mocap as well as three multimodal toy datasets. We report classification accuracy, generation accuracy, and localization accuracy and demonstrate its superiority compared to the state-of-the-art methods. 相似文献
60.
Diazotized aryl amines were coupled with 2-aminothiazoles 1 and 2 to give the corresponding thiazolylazo dyes 3 and 4, respectively. 2-Amino-5-arylazothiazoles 5 reacted with chloroacetyl chloride to afford the chloro-acetamide derivatives 6 which further reacted with 2-mercaptobenzothiazole to furnish a new series of 5-arylazothiazolyl dyes 7. The azo structure of the dyes (rather than the tautomeric hydrazo structure) was assessed by ab initio DFT calculations at the B3LYP/6-31G* level. These dyes were applied to polyester fabric as disperse dyes and their fastness properties were evaluated. 相似文献