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排序方式: 共有361条查询结果,搜索用时 46 毫秒
11.
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Stephen R. Schach Tokunbo O. S. Adeshiyan Daniel Balasubramanian Gabor Madl Esteban P. Osses Sameer Singh Karlkim Suwanmongkol Minhui Xie Dror G. Feitelson 《Software Quality Journal》2007,15(1):99-113
Both common coupling and pointer variables can exert a deleterious effect on the quality of software. The situation is exacerbated
when global variables are assigned to pointer variables, that is, when an alias to a global variable is created. When this
occurs, the number of global variables increases, and it becomes considerably harder to compute quality metrics correctly.
However, unless aliasing is taken into account, variables may incorrectly appear to be unreferenced (neither defined nor used),
or to be used without being defined. These ideas are illustrated by means of a case study of common coupling in the Linux
kernel.
相似文献
Stephen R. SchachEmail: |
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O. Smuk P. Nenonen H. Hänninen J. Liimatainen 《Metallurgical and Materials Transactions A》2004,35(7):2103-2109
The microstructures of a powder metallurgy/hot-isostatically pressed super duplex stainless steel, designed and manufactured
for massive components of paper machines, were studied after heat treatments simulating the industrial production. It was
shown that copper precipitates in the ferrite phase as ɛ phase. Morphologically, the copper precipitates are of two types—nearly spherical particles of typical size from 30 to 50
nm, and rodlike particles 30- to 35-nm wide, and up to 700-nm long. The main observations on copper precipitation in modern
super duplex stainless steels are similar to those in low-alloy steels. Copper particles were shown to be the nucleation sites
for the formation of secondary austenite and to pin the boundaries of sigma phase. 相似文献
15.
Vladimir V. Pushkarev Zhongwei Zhu Kwangjin An Antoine Hervier Gabor A. Somorjai 《Topics in Catalysis》2012,55(19-20):1257-1275
We aim to develop novel catalysts that exhibit high activity, selectivity and stability under real catalytic conditions. In the recent decades, the fast development of nanoscience and nanotechnology has allowed synthesis of nanoparticles with well-defined size, shape and composition using colloidal methods. Utilization of mesoporous oxide supports effectively prevents the nanoparticles from aggregating at high temperatures and high pressures. Nanoparticles of less than 2?nm sizes were found to show unique activity and selectivity during reactions, which was due to the special surface electronic structure and atomic arrangements that are present at small particle surfaces. While oxide support materials are employed to stabilize metal nanoparticles under working conditions, the supports are also known to strongly interact with the metals through encapsulation, adsorbate spillover, and charge transfer. These factors change the catalytic performance of the metal catalysts as well as the conductivity of oxides. The employment of new in situ techniques, mainly high-pressure scanning tunneling microscopy (HPSTM) and ambient-pressure X-ray photoelectron spectroscopy (APXPS) allows the determination of the surface structure and chemical states under reaction conditions. HPSTM has identified the importance of both adsorbate mobility to catalytic turnovers and the metal substrate reconstruction driven by gaseous reactants such as CO and O2. APXPS is able to monitor both reacting species at catalyst surfaces and the oxidation state of the catalyst while it is being exposed to gases. The surface composition of bimetallic nanoparticles depends on whether the catalysts are under oxidizing or reducing conditions, which is further correlated with the catalysis by the bimetallic catalytic systems. The product selectivity in multipath reactions correlates with the size and shape of monodisperse metal nanoparticle catalysts in structure sensitive reactions. 相似文献
16.
Francesco
Borgioli David Hajdu Tamas Insperger Gabor Stepan Wim Michiels 《International journal for numerical methods in engineering》2020,121(16):3505-3528
The article presents a pseudospectral approach to assess the stability robustness of linear time-periodic delay systems, where periodic functions potentially present discontinuities and the delays may also periodically vary in time. The considered systems are subject to linear real-valued time-periodic uncertainties affecting the coefficient matrices, and the presented method is able to fully exploit structure and potential interdependencies among the uncertainties. The assessment of robustness relies on the computation of the pseudospectral radius of the monodromy operator, namely, the largest Floquet multiplier that the system can attain within a given range of perturbations. Instrumental to the adopted novel approach, a solver for the computation of Floquet multipliers is introduced, which results into the solution of a generalized eigenvalue problem which is linear w.r.t. (samples of) the original system matrices. We provide numerical simulations for popular applications modeled by time-periodic delay systems, such as the inverted pendulum subject to an act-and-wait controller, a single-degree-of-freedom milling model and a turning operation with spindle speed variation. 相似文献
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Amalia Mesaros Cristina D. Ghitulica Mihaela Popa Raluca Mereu Adriana Popa Traian Petrisor Jr. Mihai Gabor Adrian Ionut Cadis Bogdan S. Vasile 《Ceramics International》2014
Zn1−xCoxO (x==0.05, 0.10, 0.15) nanoparticles have been synthesized by an alternative wet-chemical synthesis route using the SimAdd technique. The as-obtained powders were investigated by FT-IR spectroscopy, X-ray diffraction and thermal analysis correlated with evolved gas analysis (TG–DTA–FT-IR) in order to determine their chemical nature, crystalline structure and to establish the decomposition sequences. The precipitates are generally amorphous, but low-intensity reflection peaks assigned both to the zinc oxalate dihydrate, and zinc hydroxide can be observed in the recorded patterns, indicating that hydroxy-oxalate precipitates were obtained. The structure, morphology and magnetic properties of the thermally treated samples have been investigated by X-ray diffraction, FT-IR, HRTEM, SAED, UV–vis and EPR. XRD studies reveal a hexagonal wurtzite-type structure for all Zn1−xCoxO samples. TEM investigations show particle size between 28 and 37 nm, with spherical and polyhedral shapes and with tendency to form aggregates. The presence of a Co3O4 secondary phase was evidenced by XRD, UV–vis and EPR for the Zn0.85Co0.15O sample. The ferromagnetic behavior of the samples was revealed. The paper highlights that by varying the cobalt concentration it is possible to modulate the structural, morphological, optical and magnetic properties. 相似文献
19.
Bozoki Z Mohacsi A Szabo G Bor Z Erdelyi M Chen W Tittel FK 《Applied spectroscopy》2002,56(6):715-719
A photoacoustic spectroscopic (PAS) and a direct optical absorption spectroscopic (OAS) gas sensor, both using continuous-wave room-temperature diode lasers operating at 1531.8 nm, were compared on the basis of ammonia detection. Excellent linear correlation between the detector signals of the two systems was found. Although the physical properties and the mode of operation of both sensors were significantly different, their performances were found to be remarkably similar, with a sub-ppm level minimum detectable concentration of ammonia and a fast response time in the range of a few minutes. 相似文献
20.
Design tool integration is a highly relevant area of software engineering that can greatly improve the efficiency of development processes. Design patterns have been widely recognized as important contributors to the success of software systems. This paper describes and compares two large-grain, architectural design patterns that solve specific design tool integration problems. Both patterns have been implemented and used in real-life engineering processes. 相似文献