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11.
Xing Zhang Lijun Yin Jeffrey F. Cohn Shaun Canavan Michael Reale Andy Horowitz Peng Liu Jeffrey M. Girard 《Image and vision computing》2014
Facial expression is central to human experience. Its efficiency and valid measurement are challenges that automated facial image analysis seeks to address. Most publically available databases are limited to 2D static images or video of posed facial behavior. Because posed and un-posed (aka “spontaneous”) facial expressions differ along several dimensions including complexity and timing, well-annotated video of un-posed facial behavior is needed. Moreover, because the face is a three-dimensional deformable object, 2D video may be insufficient, and therefore 3D video archives are required. We present a newly developed 3D video database of spontaneous facial expressions in a diverse group of young adults. Well-validated emotion inductions were used to elicit expressions of emotion and paralinguistic communication. Frame-level ground-truth for facial actions was obtained using the Facial Action Coding System. Facial features were tracked in both 2D and 3D domains. To the best of our knowledge, this new database is the first of its kind for the public. The work promotes the exploration of 3D spatiotemporal features in subtle facial expression, better understanding of the relation between pose and motion dynamics in facial action units, and deeper understanding of naturally occurring facial action. 相似文献
12.
Shahin Pourrahimi John Williams William Punchard James Tuttle Michael DiPirro Edgar Canavan Peter Shirron 《低温学》2008,48(5-6):253-257
An important consideration in the use of magnets in adiabatic demagnetization refrigeration (ADR) applications is shielding of the other instruments in the vicinity of the superconducting magnets. Shielding without proper optimization can add unnecessary weight to the magnet system that can amount to a few times the weight of the superconducting magnet itself. This article reports on examination of various approaches to shielding of ADR magnets, and measurements conducted on both passive and active shielding of a sample Nb3Sn solenoidal magnet. Shielded ADR solenoidal magnets are also compared with self-shielding toroidal magnets in terms of overall weight, volume, and cooling capacity. 相似文献
13.
Peter Shirron Edgar Canavan Michael DiPirro Michael Jackson Todd King John Panek James Tuttle 《低温学》2001,41(11-12)
We present test results of the first adiabatic demagnetization refrigerator (ADR) that produce true continuous cooling at sub-kelvin temperatures. This system uses multiple stages that operate in sequence to cascade heat from a “continuous” stage up to a heat sink. Continuous operation avoids the usual constraints of long hold times and short recycle times that lead to the generally large mass of single-shot ADRs, and allows us to achieve much higher cooling power per unit mass. Our design goal is 10 μW of cooling at 50 mK while rejecting heat to a 6–10 K heat sink. The total cold mass is estimated to be less than 10 kg, including magnetic shielding of each stage. These parameters envelop the requirements for currently planned astronomy missions. The relatively high temperature heat rejection capability allows it to operate with a mechanical cryocooler as part of a cryogen-free, low temperature cooling system. This has the advantages of long mission life and reduced complexity and cost. At present, we have assembled a three-stage ADR that operates with a superfluid helium bath. Additional work is underway to develop magnetocaloric materials that can extend its heat rejection capability up to 10 K. Design, operation and performance of the ADR are discussed. 相似文献
14.
Roy F. Canavan 《Fire Technology》1980,16(1):5-11
Rockwood tested all its foam concentrates on gasohol, a mixture of gasoline and alcohol. This paper discusses the results of those tests, offers an explanation of the results, and makes some suggestions about handling gasohol emergencies. 相似文献
15.
Bracke-Tolkmitt R.; Linden A.; Canavan A. G. M.; Rockstroh B.; Scholz E.; Wessel K.; Diener H.-C. 《Canadian Metallurgical Quarterly》1989,103(2):442
The cerebellum is known to play a role in simple associative motor learning in animals. It has recently been suggested that the cerebellum might also contribute to cognitive abilities in humans, particularly those located primarily in frontal cortex. Therefore 5 patients with either cerebellar lesions or atrophy were compared with 10 controls on a range of intellectual and learning abilities. The patients were impaired on two tests of associative learning, but not on many other types of memory test. There was, however, a generalized tendency toward poorer performance by the patients. The results nevertheless indicate that the cerebellum contributes to a particular type of mental skill, although whether this is related to frontal lobe functions remains to be determined. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
16.
TP Canavan 《Canadian Metallurgical Quarterly》1998,58(9):2077-84, 2087-8
The intrauterine device, a common form of birth control in the early 1970s, is now avoided by American physicians and women because of concern about complications. This concern is largely the result of the problems reported with use of an intrauterine device that is no longer manufactured. More recent intrauterine devices have an improved design, and reevaluation has shown them to be a safe, efficacious and cost-effective form of birth control. Careful patient selection and preinsertion counseling are crucial to success with the device. Recent studies conclude that the intrauterine device poses no increased risk of pelvic inflammatory disease or infertility when used by appropriately selected patients. 相似文献
17.
The determination of detectable amounts of lead contamination in blood, foods and biological materials has been a recent problem in relation to the operation of lead mining in the West of Ireland. Following the mining activities, the incidence of lead contamination was investigated in the following ways: (i) lead values in viscera, blood and faeces of dead animals and control of lead contamination in blood, faeces and milk of live animals in mining areas; (ii) examination of pastures in areas adjoining mining operations and road dust; (iii) analysis of foods, milks and waters in the mine vicinity; and (iv) lead content in workers blood due to exposure in mines. Investigations under (i), (ii) and (iii) are dealt with in this paper. As a result of the toxicity results found in the laboratory, the mining authorities instituted precautionary steps in the mining operations to eliminate lead ‘fallout’. 相似文献
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19.
Potential nitrate removal in a coastal freshwater sediment (Haringvliet Lake, The Netherlands) and response to salinization 总被引:3,自引:0,他引:3
Nitrogen transformations and their response to salinization were studied in bottom sediment of a coastal freshwater lake (Haringvliet Lake, The Netherlands). The lake was formed as the result of a river impoundment along the south-western coast of the Netherlands, and is currently targeted for restoration of estuarine conditions. Nitrate porewater profiles indicate complete removal of NO(3)(-) within the upper few millimeters of sediment. Rapid NO(3)(-) consumption is consistent with the high potential rates of nitrate reduction (up to 200 nmol N cm(-3) h(-1)) measured with flow-through reactors (FTRs) on intact sediment slices. Acetylene-block FTR experiments indicate that complete denitrification accounts for approximately half of the nitrate reducing activity. The remaining NO(3)(-) reduction is due to incomplete denitrification and alternative reaction pathways, most likely dissimilatory nitrate reduction to NH(4)(+) (DNRA). Results of FTR experiments further indicate that increasing bottom water salinity may lead to a transient release of NH(4)(+) and dissolved organic carbon from the sediment, and enhance the rates of nitrate reduction and nitrite production. Increased salinity may thus, at least temporarily, increase the efflux of NH(4)(+) from the sediment to the surface water. This work shows that salinity affects the relative importance of denitrification compared to alternative nitrate reduction pathways, limiting the ability of denitrification to remove bioavailable nitrogen from aquatic ecosystems. 相似文献
20.
Baio JE Weidner T Interlandi G Mendoza-Barrera C Canavan HE Michel R Castner DG 《Journal of vacuum science & technology. B》2011,29(4):4D113
In this study the binding and assembly of bovine serum albumin (BSA) onto three different calcium phosphate phases (hydroxyapatite, dibasic calcium phosphate dihydrate, and β-tricalcium phosphate) was investigated using a combination of X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). XPS was used to record adsorption isotherms and to quantify the amount of BSA adsorbed onto the different CaP surfaces. On all three surfaces a monolayer of adsorbed BSA was formed. ToF-SIMS was then used to investigate how the structure of BSA changes upon surface binding. ToF-SIMS data from BSA films on the three CaP surfaces showed intensity differences of secondary ions originating from both hydrophobic and hydrophilic amino acids. For a more quantitative examination of structural changes, we developed a ratio comparing the sum of intensities of secondary ions from hydrophobic and hydrophilic residues. A small, but statistically significant, increase in the value of this ratio (7%) was observed between a BSA film on hydroxyapatite versus dibasic calcium phosphate dihydrate. From this ratio we can make some initial hypotheses about what specific changes in BSA structure relate to these differences observed in the ToF-SIMS data. 相似文献