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111.
Comment on the article "Feedback from bachelor of arts psychology graduates" by W. Leslie Barnette, Jr. (see record 1962-02017-001). The reviewer states that the study conducted in this article shows some interesting parallels to a similar study conducted at Southern Illinois University at about the same time. All but one of the BA psychology graduates were sent a questionnaire regarding their retrospective evaluation of our undergraduate psychology program. With one follow-up letter, an 80% return was obtained. Of these, 55% had taken or were taking graduate work in psychology, while the remainder were mostly distributed in professional, sales and managerial, and military positions. When asked if they would major in psychology again 80% said they would. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
112.
113.
Dominic D. J. Chandar Jayanarayanan Sitaraman Dimitri Mavriplis 《The Journal of supercomputing》2014,67(1):47-68
The application of graphics processing units (GPU) to solve partial differential equations is gaining popularity with the advent of improved computer hardware. Various lower level interfaces exist that allow the user to access GPU specific functions. One such interface is NVIDIA’s Compute Unified Device Architecture (CUDA) library. However, porting existing codes to run on the GPU requires the user to write kernels that execute on multiple cores, in the form of Single Instruction Multiple Data (SIMD). In the present work, a higher level framework, termed CU++, has been developed that uses object oriented programming techniques available in C++ such as polymorphism, operator overloading, and template meta programming. Using this approach, CUDA kernels can be generated automatically during compile time. Briefly, CU++ allows a code developer with just C/C++ knowledge to write computer programs that will execute on the GPU without any knowledge of specific programming techniques in CUDA. This approach is tremendously beneficial for Computational Fluid Dynamics (CFD) code development because it mitigates the necessity of creating hundreds of GPU kernels for various purposes. In its current form, CU++ provides a framework for parallel array arithmetic, simplified data structures to interface with the GPU, and smart array indexing. An implementation of heterogeneous parallelism, i.e., utilizing multiple GPUs to simultaneously process a partitioned grid system with communication at the interfaces using Message Passing Interface (MPI) has been developed and tested. 相似文献
114.
本文以MOC5010为基础元件,根据焊接过程微机控制系统的特点,设计了用于电流电压检测及数字控制回路中的线性光电耦合电路,实验结果及实际应用证明:该电路良好地达到了预期的目的。 相似文献
115.
Plant photosynthesis is critical for understanding carbon cycling at landscape and global scales. While tower-based measurements of CO2 have enhanced our knowledge of ecosystem fluxes, scaling these measurements globally is difficult. Satellite observations provide full, global coverage and hold the potential of spatially continuous measurements of ecosystem fluxes, but the requirements for modeling these fluxes from satellite-derived surface parameters are not well understood. This article describes the further development of a tower-mounted, automated, multiangular spectroradiometer system (AMSPEC II) used to study the relationships between canopy-reflectance and plant-physiological processes from multiangular observations, thereby facilitating a comprehensive modeling of the bidirectional reflectance distribution of the canopy. A Webcam permits simultaneous monitoring of phenological changes over time. 相似文献
116.
Dominic Phelan Mark Reid Nicole Stanford Rian Dippenaar 《JOM Journal of the Minerals, Metals and Materials Society》2006,58(9):67-69
An in-situ laser-scanning confocal microscopy study has been undertaken on the phase transformations in highpurity titanium. Observations of the β-Ti to α-Ti were observed to proceed with a pronounced Widmanstätten plate morphology due to the large β-Ti grain size. An anomalous transformation was also observed, with the α-Ti growing with a defined ledge-like surface relief. The observed transformation morphologies are discussed with reference to the crystallography of the regions, analyzed using electron-backscatter diffraction. 相似文献
117.
Jeremy Andy Dominic Ahmad Zaharin Aris Wan Nor Azmin Sulaiman Wan Zakaria Wan Md Tahir 《Urban Water Journal》2017,14(10):1075-1082
The objective of the study is to develop a spatial prediction model of sand mass and organic matter distribution in an urban stormwater holding pond using in situ measured wet sediment bulk density profile data to spatially distinguish the most likely contaminated sediment deposit areas. The wet bulk density profiles of deposited sediment at 25 locations in the Berembang (Malaysia) stormwater holding pond were measured using a single-probe nuclear density gauge. The sand and organic matter compositions of the surface sediment sample, 5 cm thickness from the bed surface, were determined. Discriminant analysis (DA) was conducted to generate two Fisher’s linear discriminant functions for the prediction of sand mass and organic matter composition areas, respectively. The linear discriminant functions generated better area classifications of surface organic matter composition compared to the sand mass distribution using wet sediment bulk density data measured at more than 15 cm depth levels. 相似文献
118.
Arora M Hare D Austin C Smith DR Doble P 《The Science of the total environment》2011,409(7):1315-1319
Emerging evidence indicates that excessive exposure to manganese (Mn) during the prenatal period and early childhood may result in neurodevelopmental deficits. However, accurate exposure biomarkers are not well established, limiting our understanding of exposure-response relationships over these susceptible periods of development. Naturally shed deciduous teeth are potentially a useful biomarker of environmental exposure to Mn. However, the uptake and distribution of Mn in human teeth has not been studied in detail.Mn distribution was measured at high resolution (~ 20 μm) in eight human primary teeth using laser ablation-inductively coupled plasma-mass spectrometry. A bio-imaging methodology was applied to construct detailed elemental maps of three incisors, and bone meal (NIST SRM 1486) was used to validate the analyses.The distribution of Mn in enamel and coronal dentine showed a distinct and reproducible pattern. In enamel, the 55Mn:43Ca ratio was highest at the outer edge of enamel (range = 0.57 to 4.74) for approximately 20-40 μm but was substantially lower in deeper layers (range = 0.005 to 0.013). The highest levels of Mn were observed in dentine immediately adjacent the pulpal margin (55Mn:43Ca range = 2.27 to 6.95). Importantly, a clearly demarcated high Mn zone was observed in dentine at the incisal end of the teeth. Using confocal laser scanning microscopy to visualize the neonatal line, this region was identified as being in the prenatally formed dentine.The high-resolution map of the spatial distribution of Mn in human primary teeth highlighted specific reproducible patterns of Mn distribution in enamel and coronal dentine. 相似文献
119.
Samia Ayari Dominic Dussault Mathieu Millette Mokhtar Hamdi Monique Lacroix 《International journal of food microbiology》2009,135(1):1-6
This present study was carried out to evaluate the effects of gamma irradiation on the fatty acids (FA) and mureins composition of two different radiotolerant bacteria. Bacillus cereus LSPQ 2872 and Salmonella Typhi ATCC 19430 were used for this study. The bacterial strains were treated with a sublethal radiation dose of 1 kGy to cause a cellular damage. Gas chromatography (GC) and high performance liquid chromatography (HPLC) analysis were performed to demonstrate respectively the modification of the FA composition and the changes in muropeptide profile. Results obtained show, for both bacteria, that this treatment had a significant effect (P ≤ 0.05) on the FA content with an increase of unsaturated FA percentage. Substantial changes were also noticed for the relative percentage and the number of the muropeptides. This study represents one of the few to demonstrate the modifications on bacterial membrane as a cellular response to survive the ionising radiation stress. 相似文献
120.
Laricar Dominic O. Trani Buddhima Indraratna 《Canadian Metallurgical Quarterly》2010,136(10):1469-1474
Gravimetric and volumetric sampling techniques are reliable for the measurement of porosity in fully saturated granular filters. However, both methods require a significant effort to gather and prepare samples, are time intensive to process, and do not capture real-time changes. Portable impedance probes serve as a valuable alternative to these destructive and laborious sampling methods. These probes measure the dielectric properties of the soil-water mixtures from which the porosity of filters may be inferred. This study demonstrates that generalized calibrations can result in large errors for porosity estimation when using diverse and small-scale filter types. By comparing with gravimetric and volumetric based porosity measurements for saturated granular filter porosity, impedance probes with filter-specific calibration offer the reliability and confidence owing to its reduced error in a quick, nondestructive fashion. This paper also presents the results of a laboratory investigation using an impedance probe to monitor real-time changes in the porosity of saturated granular filters subjected to cyclic train loading. 相似文献