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131.
The purpose of this work is to examine the basic foundations, similarities and fundamental differences between the finite element methods (FEM) and the lumped parameter methods (LPM) of analysis for oceanic cables under hydrodynamic load conditions. The continuum method (CM) is presented as a ‘ground truth’ prior to presenting each aspect of the approximate method derivations.  相似文献   
132.
133.
The Rigby-Bethune rapid methods for determining bitterness in beer are compared with Moltke-Meilgaard measurements. A new assay is presented which is suitable for the determination of bitterness in beers flavoured with isohumulone concentrates.  相似文献   
134.
A series of experiments by the authors assumes that many people in our society are motivated to aid others who are dependent upon them because such help is prescribed by a "social responsibility norm." The present study also assumes that prior help can increase the salience of this norm. In a 2 X 2 X 2 factorial design using 80 Ss (college women), ? of the Ss were individually helped by a peer (E's confederate) on a preliminary task, while the others were not aided. After this, the Ss worked on another task under the supposed supervision of yet another peer, with ? of the Ss being told the supervisor was highly dependent upon their work and the others told she was less dependent upon them. The 1st peer would supposedly learn of their work in ? of the cases but not in the other ?. The previously helped Ss tended to exert the greatest effort in behalf of their dependent peer. A self-report scale assessing social responsibility tendencies was significantly correlated with the effort measure in the Prior Help-High Dependency condition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
135.
This paper describes a system for structure from motion using vanishing points and three-dimensional lines extracted from omni-directional video sequences. To track lines, we use a novel dynamic programming approach to improve ambiguity resolution, and we use delayed states to aid in the initialization of landmarks. By reobserving vanishing points we get direct measurements of the robots three-dimensional attitude that are independent of its position. Using vanishing points simplifies the representation since parallel lines share the same direction states. We show the performance of the system in various indoor and outdoor environments and include comparisons with independent two-dimensional reference maps for each experiment .  相似文献   
136.
A dynamical model for generating synthetic electrocardiogram signals   总被引:14,自引:0,他引:14  
A dynamical model based on three coupled ordinary differential equations is introduced which is capable of generating realistic synthetic electrocardiogram (ECG) signals. The operator can specify the mean and standard deviation of the heart rate, the morphology of the PQRST cycle, and the power spectrum of the RR tachogram. In particular, both respiratory sinus arrhythmia at the high frequencies (HFs) and Mayer waves at the low frequencies (LFs) together with the LF/HF ratio are incorporated in the model. Much of the beat-to-beat variation in morphology and timing of the human ECG, including QT dispersion and R-peak amplitude modulation are shown to result. This model may be employed to assess biomedical signal processing techniques which are used to compute clinical statistics from the ECG.  相似文献   
137.
The molecular formulas for the structures and substructures of muraymycin antibiotics A1 (C52H90N14O19, MW 1214) and B1 (C49H83N11O18, MW 1113) were determined using electrospray ionization (ESI) Fourier transform mass spectrometry (FTMS). The muraymycin A1 and B1 structures were elucidated by utilizing capillary-skimmer fragmentation with up to five stages of mass spectrometry (MS5). Multi-CHEF, a multiple ion isolation method, was used at each stage of MS(n) to isolate a parent ion and up to four reference ions, for exact-mass calibration. The parent ions were fragmented by SORI-CID and the product ions internally calibrated with average absolute mass errors less than 1 ppm at each stage in the fragmentation processes. Using the top-down/bottom-up approach, the molecular formulas for the antibiotics were determined by summing the elemental formulas of the neutral losses, obtained by measuring the mass differences (<500 Da) between the genetically related sequential parent ion masses in the MS(n) spectra, with the unique elemental formula of the lowest parent ion mass (<500 Da). The structures of 12 additional compounds in the muraymycin complex were elucidated using HPLC ESI capillary-skimmer CID FTMS by correlating their fragmentation patterns with those of muraymycins A1 and B1. Sequential neutral losses of an aminosugar, a valine, a uridine, and an ester fatty acid from the muraymycin parent ions provided diagnostic fragments for characterization.  相似文献   
138.
The phase noise resulting from white and flicker noise in a bipolar junction transistor (BJT) LC oscillator is investigated. Large signal transient time domain SPICE simulations of phase noise resulting from the random-phase flicker and white noise in a 2 GHz BJT LC oscillator have been performed and demonstrated. The simulation results of this new technique are compared with Eldo RF and Spectre RF based on linear circuit concepts and experimental result reported in the literature.  相似文献   
139.
Processes of ethical decision-making are thought to depend on the issue faced when making the decision. We examined the processes by examining student's reactions to five scenarios involving IT use. Data were collected using a questionnaire following a group discussion. The results showed that ethical decision-making processes did indeed vary by scenario, suggesting that a single-issue approach is inadequate for studying ethical decision-making. Perceived importance of the ethical issue was a factor in the scenarios, but it did not have an all-inclusive influence on the decision-making of the participants. The results were considered in the context of theories and Mason's ethical issues of the information age. We offer advice to managers on how to limit unethical behavior.  相似文献   
140.
[Correction Notice: An erratum for this article was reported in Vol 122(1) of Behavioral Neuroscience (see record 2008-01943-025). In the original article, the n values (and corresponding percentages) for the number of people with the A1/A1 & A1/A2 and A2/A2 genotypes were reversed in Table 2. The corrected table appears in the erratum, with the revised numbers appearing in bold font.] The authors measured food reinforcement, polymorphisms of the dopamine D? receptor (DRD?) and dopamine transporter (DAT1) genes, and laboratory energy intake in 29 obese and 45 nonobese humans 18-40 years old. Food reinforcement was greater in obese than in nonobese individuals, especially in obese individuals with the TaqI A1 allele. Energy intake was greater for individuals high in food reinforcement and greatest in those high in food reinforcement with the TaqI A1 allele. No effect of the DAT1 genotype was observed. These data show that individual differences in food reinforcement may be important for obesity and that the DRD? genotype may interact with food reinforcement to influence energy intake. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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