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排序方式: 共有418条查询结果,搜索用时 15 毫秒
31.
Ayse Tosun Oscar Dieste Davide Fucci Sira Vegas Burak Turhan Hakan Erdogmus Adrian Santos Markku Oivo Kimmo Toro Janne Jarvinen Natalia Juristo 《Empirical Software Engineering》2017,22(6):2763-2805
Existing empirical studies on test-driven development (TDD) report different conclusions about its effects on quality and productivity. Very few of those studies are experiments conducted with software professionals in industry. We aim to analyse the effects of TDD on the external quality of the work done and the productivity of developers in an industrial setting. We conducted an experiment with 24 professionals from three different sites of a software organization. We chose a repeated-measures design, and asked subjects to implement TDD and incremental test last development (ITLD) in two simple tasks and a realistic application close to real-life complexity. To analyse our findings, we applied a repeated-measures general linear model procedure and a linear mixed effects procedure. We did not observe a statistical difference between the quality of the work done by subjects in both treatments. We observed that the subjects are more productive when they implement TDD on a simple task compared to ITLD, but the productivity drops significantly when applying TDD to a complex brownfield task. So, the task complexity significantly obscured the effect of TDD. Further evidence is necessary to conclude whether TDD is better or worse than ITLD in terms of external quality and productivity in an industrial setting. We found that experimental factors such as selection of tasks could dominate the findings in TDD studies. 相似文献
32.
An asymptotic high-frequency solution is presented for the problem of diffraction of acoustic waves emanating from a ring source by a semi-infinite cylindrical pipe of certain wall thickness having different internal, external and end surface impedances. Through the application of the Fourier-transform technique in conjunction with the Mode Matching method, the diffraction problem is described by a modified Wiener–Hopf equation of the second kind and then solved approximately. Various numerical results illustrating the effects of the parameters of the problem on the diffraction phenomenon are presented. 相似文献
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37.
Akin Mustafa Günsel Armağan Bilgiçli Ahmet T. Tüzün Burak Arabaci Gulnur Şaki Neslihan Yarasir M. Nilüfer 《Protection of Metals and Physical Chemistry of Surfaces》2020,56(3):609-618
Protection of Metals and Physical Chemistry of Surfaces - Corrosion inhibition effects of water-soluble peripheral substituted cobalt, copper and zinc metallophthalocyanines (CoPc (1), CuPc (2) and... 相似文献
38.
Grose JE Tam ES Timm C Scheloske M Ulgut B Parks JJ Abruña HD Harneit W Ralph DC 《Nature materials》2008,7(11):884-889
The manipulation of single magnetic molecules may enable new strategies for high-density information storage and quantum-state control. However, progress in these areas depends on developing techniques for addressing individual molecules and controlling their spin. Here, we report success in making electrical contact to individual magnetic N@C(60) molecules and measuring spin excitations in their electron tunnelling spectra. We verify that the molecules remain magnetic by observing a transition as a function of magnetic field that changes the spin quantum number and also the existence of non-equilibrium tunnelling originating from low-energy excited states. From the tunnelling spectra, we identify the charge and spin states of the molecule. The measured spectra can be reproduced theoretically by accounting for the exchange interaction between the nitrogen spin and electron(s) on the C(60) cage. 相似文献
39.
We study some general problems connected with the construction of thermodynamic models in the mechanics of two-component elastic bodies. Principal relations of the model are established on the basis of fundamental concepts and approaches of nonlinear continuum mechanics and nonequilibrium thermodynamics. We also demonstrate that systems of this sort can be described without using chemical potentials in the explicit form.Center of Mathematical Simulation. Pidstryhach Institute for Applied Problems in Mathematics and Mechanics, Ukrainian Academy of Sciences, L'viv. Translated from Fiziko-Khimicheskaya Mekhanika Materialov, Vol. 31, No. 4, pp. 7–15, July – August, 1995. 相似文献
40.
V. A. Morgun L. D. Burak A. N. Trofimov 《Journal of Engineering Physics and Thermophysics》1993,64(3):260-265
Results of an experimental investigation of an instrument for measuring high-temperature heat fluxes with a density up to 800 kW/m2 are presented.Notation qinc, Qinc
incident heat flux density
- A, , B, , x
dimensionless parameters
- Ta
adiabatic combustion temperature of fuel
- Hi
instantaneous height of furnace chamber
- H
full height of furnace chamber
- Tf
temperature of gases at the furnace outlet
- Tf
increment in the temperature of gases at the furnace outlet
- af
emissivity of furnace
- Tf
temperature of flame
- 0
Stefan—Boltzmann constant
- T
temperature on the heat pipe body
- Q
supplied power
- Erad
sensitivity of sensor
- D
hourly rate of fuel supplied to the boiler furnace
-
time
Academic Scientific Complex A. V. Luikov Institute of Heat and Mass Transfer of the Academy of Sciences of Belarus, Minsk. I. I. Polzunov Central Boiler and Turbine Institute, St. Petersburg. Scientific and Technical Center Flame-Complex, Ust'-Ilimsk. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 64, No. 3, pp. 324–329, March, 1993 相似文献