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81.
We study the link between the indentation size effect and the density of geometrically necessary dislocations (GNDs) through the following approach: four indents of different depth and hardness were placed in a Cu single crystal using a conical indenter with a spherical tip. The deformation-induced lattice rotations below the indents were monitored via a three-dimensional electron backscattering diffraction method with a step size of 50 nm. From these data we calculated the first-order gradients of strain and the GND densities below the indents. This approach allowed us to quantify both the mechanical parameters (depth, hardness) and the lattice defects (GNDs) that are believed to be responsible for the indentation size effect. We find that the GND density does not increase with decreasing indentation depth but rather drops instead. More precisely, while the hardness increases from 2.08 GPa for the largest indent (1230 nm depth) to 2.45 GPa for the smallest one (460 nm depth) the GND density decreases from ≈2.34 × 1015 m?2 (largest indent) to ≈1.85 × 1015 m?2 (smallest indent). 相似文献
82.
Journal of Housing and the Built Environment - Urban facilities within a neighborhood are among the most important factors affecting residential satisfaction. According to the definitions of... 相似文献
83.
A signal-processing algorithm has been developed where a filter function is extracted from degraded data through mathematical operations. The filter function can then be used to restore much of the degraded content of the data through use of a deconvolution algorithm. This process can be performed without prior knowledge of the detection system, a technique known as blind deconvolution. The extraction process, designated self-deconvolving data reconstruction algorithm, has been used successfully to restore digitized photographs, digitized acoustic waveforms, and other forms of data. The process is noniterative, computationally efficient, and requires little user input. Implementation is straightforward, allowing inclusion into many types of signal-processing software and hardware. The novelty of the invention is the application of a power law and smoothing function to the degraded data in frequency space. Two methods for determining the value of the power law are discussed. The first method assumes the power law is frequency dependent. The function derived comparing the frequency spectrum of the degraded data with the spectrum of a signal with the desired frequency response. The second method assumes this function is a constant of frequency. This approach requires little knowledge of the original data or the degradation. 相似文献
84.
85.
Beach Steven R. H.; Fincham Frank D.; Amir Nader; Leonard Kenneth E. 《Canadian Metallurgical Quarterly》2005,19(2):276
This study used taxometric methods to investigate the latent structure of the construct of marital adjustment as indexed by the Marital Adjustment Test (MAT; H. J. Locke & K. M. Wallace, 1959). That is, the authors examined whether marital adjustment is best thought of as a "dimension" of adjustment only or whether there also are categorical differences between "discordant" and "nondiscordant" couples. Analyses of data provided by 447 couples married for approximately 2 years provided converging evidence for a latent category of marital discord, suggesting that marital discord can be viewed as a qualitatively distinct state experienced by approximately 20% of the couples in the current sample. Implications for marital assessment are outlined. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
This paper evaluates the performance of a geothermal heat pump in Iran. An air-to-air 5.275 kW heat pump has been changed and redesigned to a geothermal heat pump system for the first time in Iran. Air-to-air condenser has been replaced by a tube-in-tube heat exchanger and assembled system has been tested under ARI-325 standard at the national energy lab of Iran and the results have been compared with the original system. Then, local weather conditions and soil properties of Tabriz (located at the north-west of Iran) have been applied and geothermal coil has been designed. Coil has been connected to the heat pump and the average coefficient of performance (COP) of rather more than three has been recorded in cooling mode. Results obtained from experimental measurements show that horizontal GSHP systems can be used for Tabriz-like climates in Iran. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
87.
Measurements were made according to IEEE standard 644-1994 at a height of 1 m above floor level. It is concluded that none of the measurements exceeded the ACGIH threshold limit value. Among all control rooms the highest measured density amount is 0.69 μT in the control room of Ozgol substation and the lowest is 0.2 μT in the post of Shahid Firouzi. The control room of Ozgol substation is located in the second floor and bus-bars are located at a short distance from the window on the east, and so the highest recorded magnetic field is measured in this control room. Among all switchgear parts the highest amount 9.15 μT is measured in Kan substation. None of the measurements exceeded the ACGIH threshold limit value. 相似文献
88.
In this letter, we discuss the problem of unfolding the frequency spectrum for undersampled wideband data. The problem is of relevance to state-of-the-art radio frequency measurement systems, which capture repetitive waveform based on a sampling rate that violates the Nyquist constraint. The problem is presented in a compact form by the inclusion of a complex operator called the CN operator. The ease-of-use problem formulation eliminates the ambiguity caused by folded frequency spectra, in particular those with lines standing on multiples of the Nyquist frequency that are captured with erroneous amplitude and phase values. 相似文献
89.
XB Qiu YL Lin KC Thome P Pian BP Schlegel S Weremowicz JD Parvin A Dutta 《Canadian Metallurgical Quarterly》1998,273(43):27786-27793
A human protein (RUVBL1), consisting of 456 amino acids (50 kDa) and highly homologous to RuvB, was identified by using the 14-kDa subunit of replication protein A (hsRPA3) as bait in a yeast two-hybrid system. RuvB is a bacterial protein involved in genetic recombination that bears structural similarity to subunits of the RF-C clamp loader family of proteins. Fluorescence in situ hybridization analysis demonstrated that the RUVBL1 gene is located at 3q21, a region with frequent rearrangements in different types of leukemia and solid tumors. RUVBL1 co-immunoprecipitated with at least three other unidentified cellular proteins and was detected in the RNA polymerase II holoenzyme complex purified over multiple chromatographic steps. In addition, two yeast homologs, scRUVBL1 and scRUVBL2 with 70 and 42% identity to RUVBL1, respectively, were revealed by screening the complete Saccharomyces cerevisiae genome sequence. Yeast with a null mutation in scRUVBL1 was nonviable. Thus RUVBL1 is an eukaryotic member of the RuvB/clamp loader family of structurally related proteins from bacteria and eukaryotes that is essential for viability of yeast. 相似文献
90.
Those of us advocating adaptive behavior in times of scarcity and change of resources need to be more aware of the roles we are playing and of the ideas that influence our actions. Some important dimensions of the “people problem” often appear in binary opposition: institutional constraints vs individual freedom, credible vs non-credible, tangible vs abstract, restricted vs global time perspective, specialist vs generalist, voluntary vs involuntary, and progress vs decline or status quo. Several of these dimensions were central to our understanding of two transitional mechanisms in California: the Residential Building Code and the exploration of the potential of dispersed electric generators. The “people problems” of energy reach beyond the technical-science problems, and beyond educating the little people in the value of efficiency, conservation, and the impending exhaustion of fossil fuels. Indeed, they are central to any compilation of the factual basis of dispersed energy futures. Experts and decision-makers need to look within themselves for an improved understanding of what constitutes “the” energy problem and, indeed, what constitutes “the” factual basis for energy planning. 相似文献