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51.
Franko Debra L.; Striegel-Moore Ruth H.; Bean Judy; Tamer Robert; Kraemer Helena C.; Dohm Faith-Anne; Crawford Patricia B.; Schreiber George; Daniels Stephen R. 《Canadian Metallurgical Quarterly》2005,24(6):586
Depression in adolescent girls may result in negative consequences in young adulthood. The Center for Epidemiologic Studies Depression Scale (CES-D) was administered to 1,727 Black and White girls ages 16 to 18 years who participated in the National Heart, Lung, and Blood Institute's Growth and Health Study. Three years later, women in the depressed groups were more likely to be current smokers, had attained a lower level of education, and reported lower self-worth relative to the nondepressed group. Body dissatisfaction, eating concerns, and loneliness were greater in the depressed groups. Relative to Black women, White women who were moderately depressed during adolescence reported more health care services utilization in young adulthood. Prevention efforts for depressed adolescents should be broadly focused to improve young adult outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
James Newman Jr. Judy Schneider Aaron Daniel Dustin McKnight 《International Journal of Fatigue》2005,27(10-12):1432
A test program was conducted to generate threshold and near-threshold data on two aluminum alloys: 2324-T39 and 7075-T7351, using compression pre-cracking constant-amplitude (CPCA) threshold testing procedures. Compact tension specimens were tested under stress ratios (R) of 0.1, 0.4, 0.7 or 0.8. Results were compared with either existing load-reduction data from the literature or with data that were generated using the load-reduction procedures. On the 2324 alloy, very little difference was observed between the load-reduction and CPCA test methods, although the CPCA test method consistently produced slightly lower thresholds or slightly faster crack-growth rates. But on the 2324 alloy, most of the load-reduction tests used extremely low initial ΔK values to grow the cracks under load reduction, which may explain the reason for the agreement. These low ΔK values were achieved by using compression pre-cracking to initiate a crack at the crack-starter notch. In contrast, the 7075 alloy showed very large differences between the CPCA and load-reduction results in the near-threshold and threshold regimes for R=0.1 and 0.4. Results under high R conditions (R=0.7) agreed very well between the two threshold test methods. An expression was also developed to generate fatigue-crack-growth-rate data using the CPCA threshold test method that would be unaffected by compressive yielding at the crack-starter notch and produce ‘steady-state’ constant-amplitude data in the near threshold regime. 相似文献
53.
V. Chandrasekar T. K. Srinivasa Gopal R. D. Rai 《Packaging Technology and Science》2004,17(4):213-217
White button mushrooms were washed, blanched and cut longitudinally into two halves. 100 g mushroom halves was placed into each retort pouch and 90 ml hot brine (2% salt, 0.1% citric acid) was added. Retort pouches (105 µm thick) had an outer polyester layer (12.5 µm), a middle aluminium layer (12.5 µm) and an inner cast polypropylene layer (80 µm); pouch size was 20 × 16 cm, seal size 10 mm and lip size 4 mm. Pouches were fixed with thermocouples for recording the core temperature of the mushroom pieces, using a data recorder and a computer. After sealing and over‐pressure retorting at F0 = 9.6, the pouches were stored at the ambient conditions. The heat penetration parameters were calculated. The heating curve obtained was logarithmic in nature. Sensory evaluation of mushroom curry prepared from the stored mushrooms showed that the product had high acceptability (7.9 on a scale of 10) which reduced very slightly (to 7.5) during storage for 12 months. No deformity, leakage or spoilage was noticed and the product remained sterile and acceptable even after 12 months of storage at the ambient conditions (20–30°C). Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
54.
A theory, in this context, is a Boolean formula; it is used to classify instances, or truth assignments. Theories can model real-world phenomena, and can do so more or less correctly. The theory revision, or concept revision, problem is to correct a given, roughly correct concept. This problem is considered here in the model of learning with equivalence and membership queries. A revision algorithm is considered efficient if the number of queries it makes is polynomial in the revision distance between the initial theory and the target theory, and polylogarithmic in the number of variables and the size of the initial theory. The revision distance is the minimal number of syntactic revision operations, such as the deletion or addition of literals, needed to obtain the target theory from the initial theory. Efficient revision algorithms are given for Horn formulas and read-once formulas, where revision operators are restricted to deletions of variables or clauses, and for parity formulas, where revision operators include both deletions and additions of variables. We also show that the query complexity of the read-once revision algorithm is near-optimal. 相似文献
55.
Judy Schneider Ron Radzilowski 《JOM Journal of the Minerals, Metals and Materials Society》2014,66(10):2123-2129
Designers of transportation vehicles (air, land, or sea) continually seek ways to reduce vehicle weight in response to increasing fuel economy mandates, mission requirements, or other competitive pressures. One way to do this is by the selection of material types and their properties based on functional and structural requirements. While these material changes can help meet performance mandates, their implementation in a production environment relies on retaining economic competitiveness. This article traces the history of the various joining processes relevant to the current challenge in joining the very dissimilar families of steel (Fe) and aluminum (Al) alloys. 相似文献
56.
Balraj Singh Daniel Abriola Coral Baglin Vivian Demetriou Timothy Johnson Elizabeth McCutchan Gopal Mukherjee Sukhjeet Singh Alejandro Sonzogni Jagdish Tuli 《Nuclear Data Sheets》2013,114(6-7):661-749
The evaluated spectroscopic data are presented for 11 known nuclides of mass 211 (Hg, Tl, Pb, Bi, Po, At, Rn, Fr, Ra, Ac, Th). The 211Pa nuclide is included here but its identification remains uncertain. For 211Hg, 211Tl, 211Ac and 211Th nuclei, only the ground–state information is available. Their decay characteristics are mostly unknown. 211Fr is suggested to decay partially through ε decay mode, but its decay scheme remains poorly known. While high–spin excitations, including several isomers, are well studied in 211Pb, 211Bi, 211Po, 211At, 211Rn and 211Fr, the particle–transfer data are available for only 211Po and 211Bi.This evaluation was carried out as part of joint IAEA–ICTP workshop for Nuclear Structure and Decay Data, organized and hosted by the IAEA, Vienna and ICTP, Trieste, August 6–17, 2012. This work supersedes previous A=211 evaluation (2004Br45) published by E. Browne which covered literature before January 2003. 相似文献
57.
Monopiles and gravity base foundations (GBF) are two of the most commonly used foundations for offshore wind turbines. As resonance can cause damage and even failure of wind turbines, understanding the difference between the dynamic responses of monopiles and GBFs under free vibration is important. However there is little experimental data regarding their natural frequency, especially from model tests carried out at correct stress levels. This paper presents the results of novel monopile and GBF tests using a centrifuge to directly determine the natural frequency (fn) of the foundation-soil system. The natural frequencies of wind turbine monopiles and GBFs in centrifuge models were measured during harmonic loading using a piezo-actuator, with the results confirming that soil-structure interaction must be considered to obtain the system’s natural frequency as this frequency reduces substantially from fixed-base values. These results will contribute in preventing resonance induced damage in wind-turbines. 相似文献
58.
In this study, the analysis of nonlinear stability with viscoelastic ferromagnetic fluids as working media is performed by finite-amplitude perturbations. The solution of the resulting nonautonomous system of the Lorenz model (generalized Khayat–Lorenz model of four modes) is obtained numerically to measure the amount of heat transport. The effects of elastic parameters, Prandtl number, modulation parameters, buoyancy magnetic parameter, and nonbuoyancy magnetic parameter on heat transport are studied. Heat transport is quantified through the average Nusselt number, which is determined by solving the scaled Lorenz model. As limiting cases of the study, the results of Newtonian, Maxwell, Rivlin–Ericksen fluids are determined. The results obtained have been presented graphically. 相似文献
59.
This article describes the experiences of a Los Angeles inner-city neighbourhood in its attempt for revitalization. The authors headed a Community-University Partnership and worked with graduate students to offer technical support to a neighbourhood-based coalition. The students, local residents, merchants and neighbourhood institutions attempted to follow an asset-based consensus building approach to community development. The article describes the different components of their strategy for physical, economic, cultural and social revitalization, and analyzes the lessons learned from the successes and setbacks of this effort. Finally, the authors discuss some apparent limitations of the asset-based consensus approach. 相似文献
60.
M. Shahadat Hossain Sayedur Rahman Chowdhury Nani Gopal Das S.M. Sharifuzzaman Abida Sultana 《Landscape and urban planning》2009,90(3-4):119-133
Site selection is a key factor in any aquaculture operation, affecting both success and sustainability as well as solving land or water use conflicts. This study was conducted to identify suitable sites for carp farming development in urban water bodies (UWBs) of Chittagong, Bangladesh using Geographical Information Systems (GIS) based MultiCriteria Evaluation (MCE) of water, soil and infrastructure database. ASTER imagery and 14 thematic layers were analyzed with ENVI and GIS capabilities, and developed a series of GIS models to identify and prioritize the appropriate UWBs for carp farming. The study identified 487 UWBs occupying 362 ha and revealed 280 ha (77%) is the most suitable, 36 ha (10%) is moderately suitable and 46 ha (13%) is not suitable which was consistent with field verification. The results are encouraging for extension of carp culture and diversify the economic activities of the urban dwellers. 相似文献