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191.
A small private liberal arts college with engineering, is experimenting with a new undergraduate paradigm for integrating the arts, humanities, and sciences with modern technology and engineering in a way that will enhance student's technological literacy for the 21st century. Union College brings together faculty from engineering and the liberal arts so that students graduate with an understanding beyond that provided by a traditional disciplinary major. 相似文献
192.
Craig Kenneth D.; Grunau Ruth V.; Aquan-Assee Jasmin 《Canadian Metallurgical Quarterly》1988,20(4):442
Examined adult judgments of the sensory intensity and affective discomfort experienced by newborn infants subjected to heel lancing. Video-recordings of 72 infants' reactions were categorized as high or low in cry pitch and facial activity by 28 mothers and 17 fathers of other young children. Findings indicate that cry and facial activity were determinants of the ratings, but variability in facial activity was more important than variation in cry pitch. Mothers rated the Ss as experiencing the event as less intense on the sensory dimension than did fathers. Discrete facial actions, identified using the neonatal facial coding system developed by R. V. Grunau and K. D. Craig (1987) correlated with the adult ratings. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
193.
Similarity solutions are developed for the steady flow of an incompressible elastic power law fluid in an axisymmetric conical tube. Wall suction or injection and power law indices of unity are required for the existence of a solution. In diverging flows a singularity in the momentum equation exists which corresponds to a Deborah number of unity. It is shown that the similarity equation does not have a unique solution and that there may be numerous different stable physically realizable velocity profiles. 相似文献
194.
Impact of the active surface on properties of DLC films in the PACVD coating chamber. In the automotive industry, economic and stable industrial processes to apply hard coatings for tribological applications are required. Hence detailed knowledge about the influence of coating parameters on the film characteristics is essential. the following paper deals with the process of plasma activated chemical vapor deposition with focus on the effect of the parameter “active area in the coating chamber“ on the properties of diamond‐like‐carbons (DLC). the coatings are deposited in an industrial coating chamber using reactive magnetron sputtering with a pulsed bias voltage (40 kHz) and at constant pressure. During the investigation of the influence of active area and current density on the mechanical and tribological properties of the DLC films, the expected correlation between active area and current density could be confirmed. By regulating the current density, consistent film properties could be achieved, independently of the active area in the chamber. Furthermore improved wear characteristics of the film – crucial for the endurance of heavily loaded automotive components – were achieved by adapting the load pattern of the chamber. 相似文献
195.
Isabella Jasmin Giambra Lina Chianese Pasquale Ferranti Georg Erhardt 《International Dairy Journal》2010,20(3):195-202
Ovine αs1-casein (CSN1S1) allele I (CSN1S11I) was characterized at the molecular genetic and protein level. Sequencing of CSN1S1 cDNA and mature protein showed the absence of exon 7 from CSN1S11I in comparison with the C″ genetic variant of the C phenotype. This allelic aberration is correlated with a sequence difference in 5′-splice donor sequence of intron 7 (g.656T > A), leading to upstream skipping of exon 7. Consequently mRNA sequence of ovine CSN1S11I is 24 bp shorter than complete coding sequence leading to an abbreviation of eight amino acids in the mature protein, resulting in a lower degree of phosphorylation in comparison with CSN1S11C″. However CSN1S11I was expressed at a quantitative level similar to that for the C″ reference variant. Using amplified created restriction site polymerase chain reaction, a DNA-based test for identification of CSN1S11I was developed. Altogether six nucleotide substitutions were identified within intron 6 and intron 7 of CSN1S1 variants, forming three different haplotypes. 相似文献
196.
We present a decision procedure that combines reasoning about datatypes and codatatypes. The dual of the acyclicity rule for datatypes is a uniqueness rule that identifies observationally equal codatatype values, including cyclic values. The procedure decides universal problems and is composable via the Nelson–Oppen method. It has been implemented in CVC4, a state-of-the-art SMT solver. An evaluation based on problems generated from formalizations developed with Isabelle demonstrates the potential of the procedure. 相似文献
197.
Bryan CE Christopher SJ Balmer BC Wells RS 《The Science of the total environment》2007,388(1-3):325-342
Several major unusual mortality events occurring in recent years have increased the level of concern for the health of bottlenose dolphin populations along the United States Atlantic and Gulf of Mexico coasts. Trace element concentrations were examined in a population of free-ranging dolphins in Sarasota Bay, Florida, in order to develop a benchmark for future comparisons within and between populations. Whole blood (n=51) and skin (n=40) samples were collected through capture and release health assessment events during 2002-2004. Samples were analyzed for Al, V, Cr, Mn, Cu, Zn, As, Se, Rb, Sr, Mo, Cd, and Pb by inductively coupled plasma mass spectrometry (ICPMS) and Hg via atomic fluorescence spectrometry (AFS). Trace element concentrations (wet mass) in skin were 2 to 45 times greater than blood, except Cu was approximately 1.5 times higher in blood. Statistically strong correlations (p<0.05) were found for V, As, Se, Rb, Sr, and Hg between blood and skin demonstrating that these tissues can be used as effective non-lethal monitoring tools. The strongest correlation was established for Hg (r=0.9689) and concentrations in both blood and skin were above the threshold at which detrimental effects are observed in other vertebrate species. Female dolphins had significantly greater Hg concentrations in blood and skin and Pb concentrations in skin, relative to males. Calves exhibited significantly lower V, As, and Hg concentrations in blood and V and Hg concentrations in skin, relative to other age classes. Rubidium and Cu concentrations in skin were greatest in subadults and calves, respectively. In blood, V, Zn, and As concentrations were significantly greater in winter, relative to summer, and the opposite trend was observed for Rb and Sr concentrations. In skin, Cu and Zn concentrations were significantly greater in winter, relative to summer, and the opposite trend was observed for Mn, Rb, Cd, and Pb concentrations. The baseline concentrations and trends established in this study will serve as a benchmark for comparison and aid in sampling design for future monitoring of this population and other coastal bottlenose dolphin populations. 相似文献
198.
Occurrence of methyl triclosan, a transformation product of the bactericide triclosan, in fish from various lakes in Switzerland 总被引:1,自引:0,他引:1
Balmer ME Poiger T Droz C Romanin K Bergqvist PA Müller MD Buser HR 《Environmental science & technology》2004,38(2):390-395
The bactericide triclosan and methyl triclosan, an environmental transformation product thereof, have been previously detected in lakes and a river in Switzerland. Both compounds are emitted via wastewater treatment plants (WWTPs), with methyl triclosan probably being formed by biological methylation. Passive sampling with semi-permeable membrane devices (SPMDs) showed the presence of methyl triclosan in some lakes, suggesting some potential for bioaccumulation of the compound. In this study, we report the presence of methyl triclosan in fish (white fish, Coregonus sp.; roach, Rutilus rutilus) from various lakes in Switzerland receiving inputs from WWTPs. Identification of the compound was based on mass spectral (MS) evidence including MS/MS data. The concentrations of methyl triclosan in the fish were up to 35 ng g(-1) on a wet weight basis and up to 365 ng g(-1) on a lipid basis with concentrations in a relatively narrow range for fish from the same lake (Thunersee, 4-6 ng g(-1); Zürichsee, 32-62 ng g(-1); Pf?ffikersee, 43-56 ng g(-1); Greifensee, 165-365 ng g(-1), lipid basis). No methyl triclosan (<1 ng g(-1), lipid basis) was detected in fish (lake trout, Salmo trutta) from a remote lake in Sweden (H?bberstj?rnen) and in fish (roach) from a small lake in Switzerland with no input from WWTPs (Hüttnersee, <2-<5 ng g(-1), lipid basis). The concentrations of methyl triclosan in fish correlated (r2 = 0.85) with the ratio of population in the watershed to water throughflow of the lakes (P/Q ratio), which is considered to be a measure for the domestic burden from WWTPs to a lake. Passive sampling with SPMDs confirmed the presence of methyltriclosan in lakes and a river (Zürichsee and Greifensee; Limmat) but not in a remote mountain lake (J?risee) and in Hüttnersee. The bioconcentration factor (BCF) of methyl triclosan estimated from the fish data and SPMD-derived water concentrations was in the order of 1-2.6 x 10(5) (lipid basis) and thus in the range of other persistent organic pollutants. SPMDs were found to be reliable for monitoring low concentrations of methyl triclosan in surface water. Methyl triclosan appears to be a suitable marker for WWTP-derived lipophilic contaminants in the aquatic environment and fish. 相似文献
199.
Smajic J Hafner C Erni D 《Journal of the Optical Society of America. A, Optics, image science, and vision》2004,21(11):2223-2232
We report on the numerical structural optimization of two-dimensional photonic crystal (PhC) power dividers by using two different classes of optimization algorithms, namely, a modified truncated Newton (TN) gradient search as deterministic local optimization scheme and an evolutionary optimization representing the probabilistic global search strategies. Because of the severe accuracy requirements during optimization, the proper PhC device has been simulated by using the multiple-multipole program that is contained in the MaX-1 software package. With both optimizer classes, we found reliable and promising solutions that provide vanishing power reflection and perfect power balance at any specified frequency within the photonic bandgap. This outcome is astonishing in light of the discrete nature inherent in the underlying PhC structure, especially when the optimizer is allowed to intervene only within a very small volume of the device. Even under such limiting constraints structural optimization is not only feasible but has proven to be highly successful. 相似文献
200.
A 3-level autonomous mobile robot navigation system designed by using reasoning/search approaches 总被引:1,自引:0,他引:1
This paper describes how soft computing methodologies such as fuzzy logic, genetic algorithms and the Dempster–Shafer theory of evidence can be applied in a mobile robot navigation system. The navigation system that is considered has three navigation subsystems. The lower-level subsystem deals with the control of linear and angular volocities using a multivariable PI controller described with a full matrix. The position control of the mobile robot is at a medium level and is nonlinear. The nonlinear control design is implemented by a backstepping algorithm whose parameters are adjusted by a genetic algorithm. We propose a new extension of the controller mentioned, in order to rapidly decrease the control torques needed to achieve the desired position and orientation of the mobile robot. The high-level subsystem uses fuzzy logic and the Dempster–Shafer evidence theory to design a fusion of sensor data, map building, and path planning tasks. The fuzzy/evidence navigation based on the building of a local map, represented as an occupancy grid, with the time update is proven to be suitable for real-time applications. The path planning algorithm is based on a modified potential field method. In this algorithm, the fuzzy rules for selecting the relevant obstacles for robot motion are introduced. Also, suitable steps are taken to pull the robot out of the local minima. Particular attention is paid to detection of the robot’s trapped state and its avoidance. One of the main issues in this paper is to reduce the complexity of planning algorithms and minimize the cost of the search. The performance of the proposed system is investigated using a dynamic model of a mobile robot. Simulation results show a good quality of position tracking capabilities and obstacle avoidance behavior of the mobile robot. 相似文献