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81.
Kriengsak Panuwatwanich Rodney A. Stewart Sherif Mohamed 《Automation in Construction》2009,18(6):790-797
This paper presents a study that extends on previous empirical research, which examined the role of enabling ‘climate for innovation’ constructs in determining the level of innovation diffusion outcomes, and subsequent business performance in architectural and engineering design (AED) firms. Whilst this previous study elucidated the relationships between broad theoretical constructs, the present study was focused on targeting the significant enabling factor interrelationships with the core outcomes that result from the innovation diffusion process. To achieve this objective, a sequential mixed-method research design combining quantitative and qualitative analysis techniques was employed. The quantitative techniques included a correlation analysis to identify the strong factor relationships, followed by Structural Equation Modelling (SEM) to determine the critical pathways for enhancing innovation diffusion and ultimately heightened levels of client satisfaction. Following path model extraction, qualitative interviews with five Australian AED firms were conducted. The interview findings confirmed the uncovered significant pathways, and provided in-depth insights into how the improvement of critical enabling factors could leverage improved innovation diffusion outcomes and business performance. 相似文献
82.
Nanocrystallization and Phase Transformation in Monodispersed Ultrafine Zirconia Particles from Various Homogeneous Precipitation Methods 总被引:4,自引:0,他引:4
Michael Z.-C. Hu Rodney D. Hunt E. Andrew Payzant Camden R. Hubbard 《Journal of the American Ceramic Society》1999,82(9):2313-2320
Monodispersed ultrafine (nano- to micrometer) zirconia precursor powders were synthesized by three different physicochemical methods: (I) forced hydrolysis, (II) homogeneous precipitation in inorganic salt solutions, and (III) hydrolysis/condensation of alkoxide. The forced hydrolysis method produced monoclinic nanocrystalline particles (cube shaped) of nanometer scale, which depended largely on the initial salt concentration. Methods II and III, both involving the use of alcohol as a solvent, exhibited a faster particle formation rate and generated amorphous ultrafine (submicrometer) monodispersed microspheres, indicating that the presence of alcohol may have stimulated particle nucleation due to its low dielectric property (and, thus, the low solubility of nucleus species in mixed water-alcohol solutions). Nucleation and growth of the particles in solutions are discussed based on the measurements obtained by small-angle X-ray scattering (SAXS) and dynamic light scattering (DLS). High-temperature X-ray diffraction (HTXRD) and TGA/DTA studies elucidated the differences in phase transformation for different types of powders. The most interesting finding was the nonconventional monoclinic nanocrystal nucleation and growth that occurred prior to transformation to the tetragonal phase (at 1200°C) during the heat treatment of the nanocrystalline powders produced by the forced hydrolysis. 相似文献
83.
Fen-Ren Chien Rodney J. Clifton Steven R. Nutt 《Journal of the American Ceramic Society》1995,78(6):1537-1545
Single-crystal ingots of TiC were cut into wafer substrates for heteroepitaxial growth of SiC films. During wafer sectioning by abrasive machining, a subsurface damage zone was created. TEM observations of the damage zone revealed a stress-induced martensitic transformation from cubic TiC to rhombohedral and hexagonal structures, both involving an 8.0% contraction normal to the {111} habit plane and a shear along . It is proposed that the transformed structure is governed by the Ti sublattice, and that carbon atoms remain in octahedral coordination. The transformed phase coarsened to form a lamellar structure consisting of periodic quadlayer twins. The twins imparted hexagonal symmetry, and the lamellar phase was designated 8H. A strain gradient tensor was employed to describe the mapping of atom coordinates between the two phases. The present account constitutes the first report of this transformation in TiC. 相似文献
84.
Rodney G. TeKrony Glen D. Sanders Billy Cummins 《Canadian Metallurgical Quarterly》2004,130(2):148-153
In the early days of the Reclamation Service, the criteria for irrigability of lands generally consisted of two elements: (1) is water available? and (2) can we get the water to the land? Within a few years, many of the early projects were experiencing reduced agricultural productivity and reduced ability to repay construction loans because the soils were becoming waterlogged and saline. By 1915, construction of subsurface drainage facilities had been initiated on several projects. However, at the time, subsurface drainage was more of an art than a science. Much of the world’s experience with agricultural drainage had been gained in humid areas which were quite different from arid areas. With no standards and limited knowledge of ground water movement, these early drainage efforts met with varying degrees of success. This paper summarizes the development of scientific methods to ensure successful application of drainage in a sustainable irrigated agriculture. Reclamation has introduced these methods to solve irrigated drainage problems at the international level. This paper will address the international experience, and how the same design and construction methods and procedures are now being used to design corrective drainage facilities for dams and other major structures and to support environmental enhancement programs. 相似文献
85.
在过去12个月里我讨论了项目经理的领导力及他们对项目成功的影响.上期我考察了项目经理面对的压力及其应对机制.通常人们认为项目工作和项目经理的角色是处于压力之下的.目前我正在做关于项目导向型组织中人力资源管理的研究,其中调查的一个问题就是项目导向型组织中员工的幸福状况. 相似文献
86.
Simulation with Object Oriented Programming (SW-OOP) is a library of software modules (classes) designed to provide the software constructs necessary for programming general purpose discrete event computer simulations in Pascal.
Systems modeling and simulation has been cited by those disciplined in operations research and management science as one of the skills most frequently applied to the study, understanding and improvement of systems in industry (Law 1991).
This paper presents SW-OOP and discusses how it is used to facilitate systems modeling and simulation when computer software is developed to study a particular problem. 相似文献
87.
An unexpected transient creep behavior characterized by a stress exponent of 1 was observed at low stresses in tin alloys
strengthened by large volume fractions (>15 pct) of the precipitate SbSn. By way of solid-state precipitation, SbSn forms
as high-aspect ratio whiskers. At large volume fractions, whiskers are both directly and indirectly observed to be in direct
contact with multiple other whiskers. The transient creep behavior is attributed to a phase-boundary-enhanced diffusional
creep mechanism, possibly diffusional creep along continuous phase-boundary paths between tin grain boundaries. It is thought
that the creep behavior is, in fact, a “steady-state” behavior characteristic of the initial microstructure. The ultimate
transient nature is due to precipitate coarsening occurring with time during the creep test. 相似文献
88.
89.
This paper reports the results from investigating the feasibility of calculating flame temperature from a natural gas-fired furnace based on blackbody radiation in the visible spectral range. If successful, the visible spectral range would provide data for multi-task applications such as emission line analysis and temperature calculation simultaneously. A probe containing a lens connected to the fiber-optic cables is inserted into the furnace and pointed towards the flame. Spectral intensity data are fed back to a spectrometer and then to a monitoring computer. The approach is first applied to various furnace types using the visible range to establish a baseline for the technique. The results for temperature calculations in the visible range are then compared with those taken in the near-IR (NIR) range under the same conditions. This comparison indicates that temperatures calculated from visible region could be as accurate as the one obtained from NIR region. Challenges associated with this technique are also discussed. 相似文献
90.
Swain Rodney A.; Shinkman Paul G.; Nordholm Alan F.; Thompson Richard F. 《Canadian Metallurgical Quarterly》1992,106(5):739
Implanted rabbits with chronic stimulating electrodes in white matter underlying lobule HVI of the cerebellar cortex. Stimulation elicited movements of the face or neck and, when paired with a tone CS, produced learning comparable to that seen with peripheral unconditioned stimulus/stimuli (UCS). CS-alone trials produced extinction. Reinstatement of paired trials produced reacquisition with savings. Additional groups received either explicitly or randomly unpaired CS–UCS trials before paired conditioning. Low-frequency responding during these sessions indicated that the paired training results were associative and not due to pseudoconditioning or sensitization. Explicitly unpaired sessions retarded learning on subsequent paired trials compared with groups that received either randomly unpaired or no CS–UCS preexposure. These results are interpreted in terms of the role of the cerebellum and associated pathways in classical conditioning of motor responses. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献