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71.
The transverse mixing of quartz sand (mean particle sizes 157, 323, 794 and 1038 μm) and sodium carbonate (soda) (mean particle size 137 μm) has been investigated in a laboratory rotary drum reactor of 300 mm length and 310 mm diam. Solid movement in the drum was observed by means of colored tracers and successive exposures as well as by means of hot tracers and recording the local temperature in the bulk of particles. Three different types of the particles and bulk behaviour could be observed for stickly particles. The time constant of the mixing was estimated as a function of the rotational speed of the drum. The “cooling-down” curves of the bulk of particles were measured in a laboratory oven of 250 mm diam. and 600 mm length. The temperature variation as a function of the time can be described by the Newtonian cooling law, from which the heat transfer coefficient at the wall αw was estimated.The absolute value of αw's and their dependence on the contact time and particle diameter cannot be calculated by the heat penetration model, which disregards the film resistance at the bulk/wall contact. By taking into account this resistance a good quality of fitting can be achieved. 相似文献
72.
de Almeida Jhony Luiz Comunello Eros Sobieranski Antonio da Rocha Fernandes Anita Maria Cardoso Gabriel Schade 《Pattern Analysis & Applications》2021,24(3):907-914
Pattern Analysis and Applications - Digital holography is an imaging process able to recreate three-dimensional representations of objects from recording pattern interference among distinct waves.... 相似文献
73.
Christian Schøning Tor Grande 《JOM Journal of the Minerals, Metals and Materials Society》2006,58(2):58-61
The infiltration of molten electrolyte and sodium is known to deteriorate the refractory in aluminum electrolysis. The mineralogical
changes due to reactions with molten fluorides have previously been described throughly, while the effect of sodium has not
been considered in detail. This paper presents an experimental study of the chemical stability of some refractory materials
in sodium-rich environments. The materials were exposed to sodium vapor at 800°C for 4 hours. The mineralogical transformations
and deterioration of the materials due to reactions with sodium were analyzed by x-ray diffraction and optical and electron
microscopy. 相似文献
74.
75.
Real-time control (RTC) of urban drainage systems has been proven useful as a means to reduce pollution by combined sewer overflow discharges. So far, RTC has been investigated mainly with a sole focus on water quantity aspects. However, as measurement techniques for pollution of wastewater are advancing, pollution-based RTC might be of increasing interest. For example, turbidity data sets from an extensive measurement programme in two Paris catchments allow a detailed investigation of the benefits of using pollution-based data for RTC. This paper exemplifies this, comparing pollution-based RTC with flow-based RTC. Results suggest that pollution-based RTC indeed has some potential, particularly when measurements of water-quality characteristics are readily available. 相似文献
76.
Anita Gupta Jingyue Li Reidar Conradi Harald Rønneberg Einar Landre 《Empirical Software Engineering》2009,14(2):227-255
The benefits of software reuse have been studied for many years. Several previous studies have observed that reused software
has a lower defect density than newly built software. However, few studies have investigated empirically the reasons for this
phenomenon. To date, we have only the common sense observation that as software is reused over time, the fixed defects will
accumulate and will result in high-quality software. This paper reports on an industrial case study in a large Norwegian Oil
and Gas company, involving a reused Java class framework and two applications that use that framework. We analyzed all trouble
reports from the use of the framework and the applications according to the Orthogonal Defect Classification (ODC), followed
by a qualitative Root Cause Analysis (RCA). The results reveal that the framework has a much lower defect density in total
than one application and a slightly higher defect density than the other. In addition, the defect densities of the most severe
defects of the reused framework are similar to those of the applications that are reusing it. The results of the ODC and RCA
analyses reveal that systematic reuse (i.e. clearly defined and stable requirements, better design, hesitance to change, and
solid testing) lead to lower defect densities of the functional-type defects in the reused framework than in applications
that are reusing it. However, the different “nature” of the framework and the applications (e.g. interaction with other software,
number and complexity of business logic, and functionality of the software) may confound the causal relationship between systematic
reuse and the lower defect density of the reused software. Using the results of the study as a basis, we present an improved
overall cause–effect model between systematic reuse and lower defect density that will facilitate further studies and implementations
of software reuse.
相似文献
Anita GuptaEmail: |
77.
Mark A. Neerincx Anita H. M. Cremers Judith M. Kessens David A. van Leeuwen Khiet P. Truong 《Universal Access in the Information Society》2009,8(2):109-122
This paper presents a methodology to apply speech technology for compensating sensory, motor, cognitive and affective usage
difficulties. It distinguishes (1) an analysis of accessibility and technological issues for the identification of context-dependent
user needs and corresponding opportunities to include speech in multimodal user interfaces, and (2) an iterative generate-and-test
process to refine the interface prototype and its design rationale. Best practices show that such inclusion of speech technology,
although still imperfect in itself, can enhance both the functional and affective information and communication technology-experiences
of specific user groups, such as persons with reading difficulties, hearing-impaired, intellectually disabled, children and
older adults.
相似文献
Khiet P. TruongEmail: |
78.
Albrethsen J Kaas A Schönle E Swift P Kocova M Gammeltoft S Hansen L Mortensen HB 《Proteomics. Clinical applications》2009,3(3):383-393
Proteomics analysis of serum from patients with type 1 diabetes (T1D) may lead to novel biomarkers for prediction of disease and for patient monitoring. However, the serum proteome is highly sensitive to sample processing and before proteomics biomarker research serum cohorts should preferably be examined for potential bias between sample groups. SELDI‐TOF MS protein profiling was used for preliminary evaluation of a biological‐bank with 766 serum samples from 270 patients with T1D, collected at 18 different paediatric centers representing 15 countries in Europe and Japan over 2 years (2000–2002). Samples collected 1 (n = 270), 6 (n = 248), and 12 (n = 248) months after T1D diagnosis were grouped across centers and compared. The serum protein profiles varied with collection site and day of analysis; however, markers of sample processing were not systematically different between samples collected at different times after diagnosis. Three members of the apolipoprotein family increased with time in patient serum collected 1, 6, and 12 months after diagnosis (ANOVA, p<0.001). These results support the use of this serum cohort for further proteomic studies and illustrate the potential of high‐throughput MALDI/SELDI‐TOF MS protein profiling for evaluation of serum cohorts before proteomics biomarker research. 相似文献
79.
K. Levin Y. Zha R. J. Radtke Q. Si M. R. Norman H. -B. Schüttler 《Journal of Superconductivity》1994,7(3):563-570
We review the spin dynamics of the normal state of the cuprates with special emphasis on neutron data in both the YBa2Cu3O7– and La2–x
Sr
x
CuO4 systems. When realistic models of the Fermi surface shapes are incorporated, along with a moderate degree of spin fluctuations, we find good semiquantitative agreement with experiment for both cuprates. Building on the success of this Fermi-liquid-based scheme, we explore the implications ford-wave pairing from a number of vantage points. We conclude that our present experimental and theoretical understanding is inadequate to confirm or refute thed-wave scenario. 相似文献
80.
We have produced a multilayer transmission filter with 100 periods of Cr/C to achieve a significant phase retardation while maintaining good transmission for photon energies just below the carbon K edge. This device was installed into a polarimeter behind the SX700/3 monochromator at the Berlin synchrotron radiation laboratory, BESSY. The phase-retardation properties were observed as theoretically predicted. Agreement between experiment and calculation could be obtained by introduction of a rather small interface roughness in the simulation code (σ = 0.65 nm rms). An observed phase retardation of 5° was sufficient to permit, for the first time we believe, a complete and unambiguous polarization analysis of soft-x-ray synchrotron radiation (265-eV photon energy) with primary standards. 相似文献