Deformation mechanics of deep surface flaw cracks

A combined analytical and experimental program was conducted to determine the deformation characteristics of deep surface cracks in Mode I loading. An approximate plane finite element analysis was performed to make a parameter study on the influence of crack depth, crack geometry, and stress level on plastic zones, crack opening displacement, and back surface dimpling in Fe-3Si steel and 2219-T87 aluminum. Surface replication and profiling techniques were used to examine back surface dimple configurations in 2219-T87 aluminum. Interferometry and holography were used to evaluate the potential of various optical techniques to detect small surface dimples on large surface areas

Factors influencing adoption of conservation tillage in Australian cropping regions

The purpose of this research is to improve understanding of conservation tillage adoption decisions by identifying key biophysical and socio-economic factors influencing no-till adoption by grain growers across four Australian cropping regions. The study is based on interviews with 384 grain growers using a questionnaire aimed at eliciting perceptions relating to a range of possible long- and short-term agronomic interactions associated with the relative economic advantage of shifting to a no-tillage cropping system. Together with other farm and farmer-specific variables, a dichotomous logistic regression analysis was used to identify opportunities for research and extension to facilitate more rapid adoption decisions. The broader systems approach to considering conservation tillage adoption identified important determinants of adoption not associated with soil conservation and erosion prevention benefits. Most growers recognised the erosion-reducing benefits of no-till but it was not an important factor in explaining whether a grower was an adopter or non-adopter. Perceptions associated with shorter-term crop production benefits under no-till, such as the relative effectiveness of pre-emergent herbicides and the ability to sow crops earlier on less rainfall were influential. Employment of a consultant and increased attendance of cropping extension activities were strongly associated with no-till adoption, confirming the information and learning-intensive nature of adopting no-till cropping systems.adoption, conservation tillage, herbicide resistance, no-till, perceptions, weed management, Farm Management,

Fractional Stokes-Einstein and Debye-Stokes-Einstein relations in a network forming liquid

We study the breakdown of the Stokes-Einstein (SE) and Debye-Stokes-Einstein (DSE) relations for translational and rotational motion in a prototypical model of a network-forming liquid, the ST2 model of water. We find that the emergence of ``fractional'' SE and DSE relations at low temperature is ubiquitous in this system, with exponents that vary little over a range of distinct physical regimes. We also show that the same fractional SE relation is obeyed by both mobile and immobile dynamical heterogeneities of the liquid

Young people's attitudes to religious diversity : quantitative approaches from social psychology and empirical theology

This essay discusses the design of the quantitative component of the ‘Young People’s Attitudes to Religious Diversity’ project, conceived by Professor Robert Jackson within the Warwick Religions and Education Research Unit, and presents some preliminary findings from the data. The quantitative component followed and built on the qualitative component within a mixed method design. The argument is advanced in seven steps: introducing the major sources of theory on which the quantitative approach builds from the psychology of religion and from empirical theology; locating the empirical traditions of research among young people that have shaped the study; clarifying the notions and levels of measurement employed in the study anticipating the potential for various forms of data analysis; discussing some of the established measures incorporated in the survey; defining the ways in which the sample was structured to reflect the four nations of the UK, and London; illustrating the potential within largely descriptive cross-tabulation forms of analysis; and illustrating the potential within more sophisticated multivariate analytic models

Dynamic interaction between structure and liquid propellants in a space shuttle vehicle model, part 1 Final report

Dynamic interaction between structure and liquid propellants in space shuttle vehicle model

Exact moments in a continuous time random walk with complete memory of its history

We present a continuous time generalization of a random walk with complete memory of its history [Phys. Rev. E 70, 045101(R) (2004)] and derive exact expressions for the first four moments of the distribution of displacement when the number of steps is Poisson distributed. We analyze the asymptotic behavior of the normalized third and fourth cumulants and identify new transitions in a parameter regime where the random walk exhibits superdiffusion. These transitions, which are also present in the discrete time case, arise from the memory of the process and are not reproduced by Fokker-Planck approximations to the evolution equation of this random walk.Comment: Revtex4, 10 pages, 2 figures. v2: applications discussed, clarity improved, corrected scaling of third momen

Mystery of the Lyα Blobs

We present Spitzer Space Telescope observations of the extended Lyman α blobs associated with the z=2.38 over-density J2143-4423, the largest known structure (110 Mpc) above z=2. We detect all 4 of the Lyα blobs in all four IRAC channels and we also detect 3 out of 4 of the blobs with MIPS 24μm. Conversion from rest-wavelength 7μm to total far-infrared luminosity using locally derived correlations suggests all the detected sources are in the class of ULIRGs or even Hyper-LIRGs. We find a weak correlation between Lyα and mid-infrared emission for the Lyα blobs (L_(Lyα)/L_(bol) = 0.05-0.2%). Nearly all Lyα blobs show some evidence for interaction, either in HST imaging, or the proximity of multiple MIPS sources within the Lyα cloud. This suggests that interaction or even mergers may be related to the production of Lyα blobs. Optical through infrared SEDs of the Lyα blobs do not show a clear 1.6μm bump, but rather are indicative of a composite of star formation and AGN energy sources

Coupling between structure and liquids in a parallel stage space shuttle design

A study was conducted to determine the influence of liquid propellants on the dynamic loads for space shuttle vehicles. A parallel-stage configuration model was designed and tested to determine the influence of liquid propellants on coupled natural modes. A forty degree-of-freedom analytical model was also developed for predicting these modes. Currently available analytical models were used to represent the liquid contributions, even though coupled longitudinal and lateral motions are present in such a complex structure. Agreement between the results was found in the lower few modes

Biaxial fatigue loading of notched composites

Thin walled, 2.54-cm (1-in.) diameter tubular specimens of T300/934 graphite/epoxy were fabricated and fatigue cycled in combinations of axial, torsional, and internal pressure loading. Two different four-ply layup configurations were tested: (0/90)S and (+ or - 45)S; all tubes contained a 0.48-cm (3/16-in.) diameter circular hole penetrating one wall midway along the tube length. S-N curves were developed to characterize fatigue behavior under pure axial, torsional, or internal pressure loading, as well as combined loading fatigue. A theory was developed based on the Hill plane stress model which enabled the S-N curve for combined stress states to be predicted from the S-N data for the uniaxial loading modes. Correlation of the theory with the experimental data proved to be remarkably good

A Comprehensive Review of Congestion Management in Power System

In recent decades, restructuring has cut across all probable domains, involving the power supply industry. The restructuring has brought about considerable changes whereby electricity is now a commodity and has become a deregulated one. These competitive markets have paved the way for countless entrants. This has caused overload and congestion on transmission lines. In addition, the open access transmission network has created a more intensified congestion issue. Therefore, congestion management on power systems is relevant and central significance to the power industry. This manuscript review few congestion management techniques, consists of Reprogramming Generation (GR), Load Shedding, Optimal Distributed Generation (DG) Location, Nodal Pricing, Free Methods, Genetic Algorithm (GA), Particle Swarm Optimization (PSO), Fuzzy Logic System Method, as well as Additional Renewable Energy Sources. In this manuscript a review work is performed to unite the entire publications on congestion management