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1.
The testing and quality assurance of the Motif 1.0 graphical user-interface software are described. The testing goals, which fell into three general categories (code coverage, defect-density, and defect-arrival rate), and a deliverable formal test suite are examined. The three phases of the testing process-evaluation, test development, and regression testing-and the tools used in testing are discussed 相似文献
2.
3.
R Albrecht TC Awes C Baktash P Beckmann F Berger R Bock G Claesson G Clewing L Dragon A Eklund RL Ferguson A Franz S Garpman R Glasow HA Gustafsson HH Gutbrod J Idh P Jacobs K Kampert BW Kolb P Kristiansson IY Lee H Loehner I Lund FE Obenshain A Oskarsson I Otterlund T Peitzmann S Persson F Plasil AM Poskanzer M Purschke H Ritter S Saini R Santo HR Schmidt T Siemiarczuk SP Sorensen E Stenlund ML Tincknell GR Young 《Canadian Metallurgical Quarterly》1991,44(6):2736-2752
4.
Chandrasekhar S. Lunardi L.M. Gnauck A.H. Ritter D. Hamm R.A. Panish M.B. Qua G.J. 《Electronics letters》1992,28(5):466-468
Metal organic molecular beam epitaxy (MOMBE) was successfully used for the first time to realise a high speed monolithic photoreceiver. Incorporating an InGaAs pin photodetector followed by a transimpedance preamplifier circuit implemented with InP/InGaAs heterojunction bipolar transistors (HBTs), the OEIC photoreceiver had a bandwidth of 6 GHz and a midband transimpedance of 350 Omega . In a system experiment performed at 10 Gbit/s, the receiver exhibited a sensitivity of -15.5 dBm for a bit error rate of 10/sup -9/ at a wavelength of 1.53 mu m. This is the first demonstration of operation of a long wavelength OEIC photoreceiver at this speed.<> 相似文献
5.
X-ray powder diffraction patterns of the ferroelectric mixed crystal Sr0.39,Ba0.61Nb2O6 (SBN-39) are recorded in Guinier geometry in a temperature range between 20 K and 500 K by means of the film-lift technique. The lattice parameters were refined for a single tetragonal structure in the whole temperature range ignoring the incommensurate (IC) modulation of the structure as well as a temperature dependent small splitting of reflections, most clearly observed for the (001)-type. These values show anomalies in the region of diffuse ferroelectric phase transition as well as below room temperature indicating the three other phase transitions. The splitting may be caused by a two-phase state of a relaxor-like ferroelectric system due to coexistence of polarized regions (clusters) and untransformed remnants of the para-phase. 相似文献
6.
SC Bowden B Dodds G Whelan C Long P Dudgeon A Ritter C Clifford 《Canadian Metallurgical Quarterly》1997,19(5):755-762
Previous analyses of the Wechsler Memory Scale-Revised (WMS-R; Wechsler, 1987) have reported one-, two-, and three-factor solutions and raised questions about the validity of the visual memory subtests. These various findings may stem in part from different methods of analysis, and from the study of different participant samples. To address these issues, we analysed data from the WMS-R and a spatial maze test administered to 154 participants with a history of alcohol dependence. Results from confirmatory factor analysis supported the interpretation of three factors underlying the WMS-R subtests and the spatial maze score in this sample, namely, attention-concentration, immediate memory, and delayed recall. This result held despite the inclusion of the maze score which is a well-validated measure of visuo-spatial memory. 相似文献
7.
Composites consisting of a Ti-14Al-21Nb (wt%) aluminide matrix and SCS-6 SiC fibres were fabricated by plasma-spraying and
hot-isostatic-pressing. The room temperature longitudinal tensile properties were evaluated after processing and after isothermal
and cyclic exposure in air and in argon. The isothermal ages were performed at 760°C, and the thermal cycle was from room
temperature to 760°C, which is the projected service temperature for Ti-aluminide-based composites. Some loss of tensile strength
occurred after isothermal and cyclic exposure for long times (8 to 12 weeks) in argon, with no apparent difference in behaviour
between the isothermal and cyclic samples. Substantial degradation in tensile properties was seen after isothermal exposure
in air, while a much more severe loss in properties occurred after cycling in air. In the isothermal samples exposed in air,
degradation in properties was associated with surface embrittlement of the matrix, with the longitudinal room temperature
tensile strength decreasing linearly with increasing thickness of the embrittled zone. During air-cycling, this effect was
enhanced by a rapid decrease in the strength of the SCS-6 fibre, and an increase in the amount of fibre breakage. Isolating
the fibres from direct contact with the environment resulted in a decrease in the amount of composite strength degradation
after air-cycling.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
8.
Forty-four goats were milked and milk flow recorded without or with 1 min manual prestimulation in early, mid and late lactation. Ultrasound measurements of cross sections of the whole mammary gland were performed in a water bath. In additional experiments with 15 goats, milk flow was recorded and frequent blood samples were taken for the determination of oxytocin and prolactin concentrations. Milk yield increased from the first to the third lactation and decreased markedly during the course of lactation. Average and peak milk flow rates were closely related to the actual milk yield. The ultrasound cisternal area was 27.4 +/- 1.5% of the entire udder half cross section. Milking characteristics were scarcely different without or with prestimulation, although oxytocin was released within 30 s after the start of prestimulation, whereas oxytocin concentrations without prestimulation increased only after the start of milking. Concentrations of prolactin were higher during July and August than in April, and increased similarly with or without prestimulation during milking. In contrast to dairy cows, prestimulation and an opportune release of oxytocin during milking does not significantly influence the course of milk flow in goats, and this is probably because large amounts of cisternal milk allow milk ejection to be induced only after the start of milking without causing bimodal or otherwise reduced milk flow. 相似文献
9.
An 84-year-old male presented to the emergency room with the chief complaint of painful, swollen penis following the use of a constriction ring to maintain penile erection. A high fever, chills and hypotension were recognized. Septic shock was presumed, and administration of antibiotics was started. Microbiologic cultures revealed Escherichia coli in blood. We herein report a rare but serious complication accompanying incarceration of the penis. 相似文献
10.
Rehana Yasmin Eike Ritter Guilin Wang 《International Journal of Information Security》2014,13(5):453-465
Designing efficient as well as secure cryptographic protocols for resource-constrained applications is a challenging task. In this paper, we formally analyze the security of an efficient one-pass authenticated key establishment protocol, the 1P-AKE protocol, which is primarily proposed for resource-constrained sensor nodes devices in wireless sensor networks (WSNs). In contrast to the existing identity-based one-pass key establishment protocols, the 1P-AKE protocol does not require any bilinear pairing computation in order to establish a key. This feature makes it really attractive for resource-constrained application environments, such as WSNs, where pairing computations are too expensive. We show that in the random oracle model, the 1P-AKE protocol is a secure authenticated one-pass key establishment protocol under the computational Diffie–Hellman assumption. The performance of the 1P-AKE protocol is also discussed and compared with the existing relevant protocols. 相似文献