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41.
The free alpha amino nitrogen in wort and beer has been estimated by reaction with trinitrobenzene sulphonic acid (TNBS) either at 40°C for 2 h or at 60°C for 30 min. Statistical analysis shows that for worts there is no significant difference between results obtained under the two sets of conditions, but for beers the values are higher when determined at 60°C by amounts which vary from beer to beer. However, there is no loss in precision (± 2 SD) so that the more rapid method can be used with advantage. 相似文献
42.
The purpose of the current study was to explore how mother’s and father’s connectedness and involvement individually and collectively influence the lives of their children. Specifically, we asked how fathers’ and mothers’ parent–child connectedness and behavioral involvement influenced both problem behaviors (externalizing and internalizing behaviors) and positive outcomes (prosocial behaviors and hope) during early adolescence. Data for this study were taken from the Flourishing Families Project, from which 349 mothers and fathers were selected, along with their early adolescent child (mean age = 11.23 years, SD = .96). Hierarchical regression analyses revealed (even after controlling for child age, gender, and self-regulation) that mothers’ and fathers’ contributions differed, primarily as a function of child outcome. Namely, father (but not mother) connectedness and involvement were negatively related to adolescents’ internalizing and externalizing behaviors, whereas mother (but not father) connectedness and involvement were positively related to adolescents’ prosocial behaviors and hope. We also found that when one parent’s involvement was low (for whatever reason), the other parent’s involvement made a significant and important contribution to the child’s well-being, particularly in the area of internalizing behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
Mark S. Hickman 《Journal of Mathematical Imaging and Vision》2012,43(3):206-213
It is well known that two planar curves that are related by a Euclidean transformation possess the same signature curve. Recently Musso and Nicolodi (J. Math. Imaging Vis. 35:68–85, 2009) gave examples of non-congruent curves that possess the same Euclidean signature curve. In this paper we show how to construct all planar curves of class C 3 that have a given signature curve. 相似文献
44.
AbstractContemporary debates around affordability have largely focused on homeownership and private renting. This article considers the affordable social rented sector in England, in which reforms to social welfare assistance, reduced security of tenure, and a shift towards mid-market rents, are changing access to ‘affordable’ housing for those on the lowest incomes. Drawing on in-depth interviews with housing associations and stakeholders, the article highlights the increasing use of affordability assessments for prospective tenants. These assessments interact with mid-market rental products to increase the potential for exclusion from affordable housing on the grounds of ability to pay. This conditionality is applied not only at the point of tenancy access, but also at renewal of fixed-term tenancies. The research highlights that the combination of welfare and housing policies, in the context of a financialising housing association sector, has the potential to erode access to social housing for those who are perceived as a financial risk, reshaping the focus of social housing. 相似文献
45.
As a component of a multisensor approach to monitoring carbon sequestration sites for possible leaks of the CO? gas from underground reservoirs, a low-cost multispectral imaging system has been developed for indirect detection of gas leaks through observations of the resulting stress in overlying vegetation. The imager employs front-end optics designed to provide a full 50° field of view with a small, low-cost CMOS detector, while still maintaining quasi-collimated light through the angle-dependent interference filters used to define the spectral bands. Red and near-infrared vegetation reflectances are used to compute the normalized difference vegetation index (NDVI) and spatial and temporal patterns are analyzed statistically to identify regions of anomalous stress, which are then flagged for closer inspection with in-situ CO? sensors. The system is entirely self-contained with an onboard compact computer and is housed in a weather-proof housing to enable extended outdoor deployment. 相似文献
46.
47.
Two recently completed on-road in situ (naturalistic) data collection efforts provided a large data set in which to conduct an examination of crashes, near-crashes, and crash-relevant conflicts (referred to as critical incidents throughout this paper) that occurred between light vehicles (LV) and heavy vehicles (HV). Video and non-video data collected during the two studies were used to characterize critical incidents that were recorded between LV and HV drivers. Across both studies, 210 LV-HV critical incidents were recorded. Of these, 78% were initiated by LV drivers, while the remaining 22% were initiated by HV drivers. Aggressive driving, on the part of the LV driver, was found to be the primary Contributing Factor for LV driver-initiated incidents. For HV driver-initiated incidents, the primary Contributing Factor was poor driving techniques. These results suggest that future efforts at addressing LV-HV interaction incidents should include focusing on aggressive LV drivers. Additionally, it is recommended that HV drivers might benefit from improved driver training that includes instruction on defensive driving skills. The in situ methodology provides an alternative to traditional crash databases, developed from police accident reports, for studying crash causation and driver behavior. 相似文献
48.
Hawke R.S. Susoeff A.R. Asay J.R. Ang J.A. Hall C.A. Konrad C.H. Wellman G.W. Hickman R.J. Heath W.A. Martinez J.R. Sauve J.L. Vasey A.R. Shahinpoor M. 《IEEE transactions on magnetics》1991,27(1):28-32
Results obtained with the HELEOS (hypervelocity experimental launcher for equation of state) railgun, which uses a two-stage light-gas gun (2SLGG) as an injector, are presented. The high-velocity 2SLGG injector preaccelerates projectiles up to ~7 km/s. The high injection velocity reduces the exposure duration of the railgun barrel to the passing high temperature plasma armature, thereby reducing the ablation and subsequent armature growth. The 2SLGG also provides a column of cool, high-pressure hydrogen gas to insulate the rails behind the projectile, thereby eliminating restrike. A means to form an armature behind the injected projectile has been developed. In preliminary tests, the third-stage railgun has successfully increased the projectile velocity by 1.35 km/s. Extensive diagnostics have been used to determine the behavior of the armature and track the launcher's performance. Insome cases, velocity increases in the railgun section have been achieved, which are in close agreement with theoretical predictions, whereas in other experiments deviations from theoretical have been observed. The reasons for and implications of these results are addressed. Recent tests are reported 相似文献
49.
The authors develop an eigth-order model for bending of transversally isotropic plates and use integral transforms and a collocation
method to form a line-spring model for a cracked plate. The eigth-order model allows satisfaction of the three standard plate
bending boundary conditions; the normal moment, twisting moment, and transverse shear force, and an additional shear stress
resultant that allows analysis of transverse normal stresses near the crack tip. The line-spring model is used to develop
geometry correction factors for bending of finite-thickness plates, accounting for transverse shear deformation and pressurization
of the plate near the crack tip. The line-spring model is then applied to the problem of a plate with a reinforced crack,
and the results are used to validate an interpolation solution based on an energy method. While not explicitly analysed, the
models are applicable to many problems, including bending of bonded repairs, fracture and fatigue of composite and layered
materials, surface cracks, crack tip plasticity and crack closure or crack face interaction. 相似文献
50.
A scheme to randomly generate dust points on the surface of a three-dimensional (3D) object is proposed. This scheme will potentially eliminate the bias of a density of points which are approximately equally spaced on the surface, as well as eliminate possible weighting requirements for areas of higher density. This method has the potential to reduce computational effort, as fewer points might be required to define the surface area. The global trial function vector can be assigned to these dust points and then entered into the complex variable boundary element method (CVBEM) commercial code. This scheme can be applied to each piece of a system that is comprised of a connected multiple geometry. A noticeable benefit of this approach is that the same problem can be studied several times, using a new random distribution of surface points each time. The smallest error can then be determined and that run selected. The Mathematica code used to generate the scheme is attached as an appendix. 相似文献