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991.
Wang F.-Y. Gildea K. Jungnitz H. Chen D.D. 《Industrial Electronics, IEEE Transactions on》1994,41(6):641-653
The manufacturing message specification (MMS) is the ISO standard communication protocol specific to manufacturing. To analyze MMS design and performance, service unit automats are introduced to represent individual MMS services, while service connection Petri Nets (PNs) are constructed from these automats to describe MMS service connections and processes. This approach makes MMS protocol specification and analysis possible in terms of well-developed concepts and methods in PN theory. It leads to a distributed and hierarchical model of MMS software system by integrating service connection PNs. A generalized stochastic PN for MMS performance evaluation is obtained by incorporating service parameters and time factors into the model. A technique based on T-invariants is used to simplify the performance analysis 相似文献
992.
Enhanced performance is demonstrated in n-type metal-oxide-semiconductor field-effect transistors with channel regions formed by pseudomorphic growth of strained Si on relaxed Si1-xGex. Standard MOS fabrication techniques were utilized, including thermal oxidation of the strained Si. Surface channel devices show low-field mobility enhancements of 80% at room temperature and 12% at 10 K, when compared to control devices fabricated in Czochralski Si. Similar enhancements are observed in the device transconductance. In addition, buried channel devices show peak room temperature mobilities about three times that of control devices 相似文献
993.
Shye Lin Wu Chung Len Lee Tan Fu Lei Chen C.F. Chen L.J. Ho K.Z. Ling Y.C. 《Electron Device Letters, IEEE》1994,15(4):120-122
In this study, it is demonstrated that the incorporation of fluorine can enhance poly-Si/Si interfacial oxide break-up in the poly-Si emitter contacted p+-n shallow junction formation. The annealing temperature for breaking up the poly-Si/Si interfacial oxide has been found to be as low as 900°C. As a result, the junction depth of the BF2-implanted device is much larger than that of the boron-implanted device 相似文献
994.
Zolper J.C. Shenvin M.E. Baca A.G. Shul R.J. Klem J.F. Hietala V.M. 《Electron Device Letters, IEEE》1994,15(12):493-495
C ion implantation has been employed, for the first time, to form the buried p-layer in GaAs, self-aligned, ion implanted JFETs. Comparable DC performance was seen for JFETs with C or Mg implants; however, C-backside JFETs showed superior high-frequency performance. High dose C-backside devices had a ft of 28.3 GHz and a fmax of 43.2 GHz for a 0.5 μm gate length that were 28% and 46% higher, respectively, than comparable Mg-implanted JFETs. This enhancement is a result of the lower Cgs in the C-backside device resulting from he inherently low activation of the implanted C below the channel while the C still effectively compensated the tail of the Si-channel implant. This approach relaxes the trade-off between optimizing the DC and the AC performance for the buried p-implant in GaAs JFETs and MESFET's 相似文献
995.
Responds to M. F. Hoyt's (see record 1995-22250-001) commentary on T. F. Van Denburg and E. J. Van Denburg's (see record 1994-18427-001) response to Hoyt's (see record 1994-18395-001) commentary on Van Denburg and Van Denburg's (see record 1993-06526-001) article about a case of premature therapy termination. Issues related to limits and flexibility in treatment are addressed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
Continuous surface boundaries, object shape, and global motion can be perceived from information that is fragmentary in both space and time. The authors report investigations indicating that accretion and deletion of texture is only 1 member of a broader class of element transformations that produce boundaries, shape, and motion, through spatiotemporal boundary formation (SBF). Four experiments exploring SBF are reported. The 1st 3 examine the class of transformations producing SBF, indicating that local element changes in color, orientation, or location are all effective. A 4th experiment examines temporal constraints on SBF. Integration of local element changes to produce boundaries, form, and global motion appears to be confined to a 165-msec window. Two classes of spatiotemporal integration models are considered; the relation between SBF and other cases of boundary interpolation are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
Evaluated the contributions of strategic and data-driven factors to skilled performance by manipulating the predictability of the class of stimuli used in a memory search task. In Exp 1, when consistent mapping (CM) and varied mapping (VM) conditions were blocked, large performance differences were observed; however, when CM and VM trials were mixed, performance differences were reduced. In Exp 2, mixed training led to a less skilled performance than blocked training. Moreover, transfer conditions revealed a critical interval for learning to adopt and deploy differential response strategies. Exp 3 demonstrated that the differential response strategies were not stimulus specific. Analysis suggests that skilled performance can be conceptualized as an interaction between enhanced evidence accumulation and strategic setting of response criteria. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
Krueger Robert F.; Schmutte Pamela S.; Caspi Avshalom; Moffitt Terrie E.; Campbell Kathleen; Silva Phil A. 《Canadian Metallurgical Quarterly》1994,103(2):328
Is there a relationship between personality and criminal behavior? We addressed this question in a representative birth cohort of 862 male and female 18-yr-olds. Personality was assessed with the Multidimensional Personality Questionnaire (MPQ). The MPQ measures 10 relatively independent personality traits and was not designed to identify offenders. Delinquency was assessed via 3 data sources: self-reports, informant reports, and official records. Variable-centered analyses revealed that MPQ scales indexing negative emotionality and behavioral constraint were consistent predictors of delinquency across the 3 data sources. Person-centered analyses revealed that youths abstaining from delinquency were uniquely characterized by low interpersonal potency. Youths involved in extensive delinquency were uniquely characterized by feelings of alienation, lack of social closeness and risk taking. Advances in understanding criminal behavior can be made through research that places the personality-delinquency link in a developmental context. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
J Jassem H Karnicka-M?odkowska C van Pottelsberghe M van Glabbeke MA Noseda A Ardizzoni F Gozzelino A Planting N van Zandwijk 《Canadian Metallurgical Quarterly》1993,(12):1720-1722
26 previously treated patients with progressive recurrent small cell lung cancer (SCLC) were given vinorelbine (Navelbine), 30 mg/m2 weekly. All patients had responded to first-line chemotherapy and were off therapy for at least 3 months. Partial response was observed in 4 out of 25 eligible patients (16%; 95% confidence interval 4-36%), stable disease in 7 patients and progression in 12 patients. The limiting toxicity was a non-cumulative leucopenia (80%, 32% WHO grade 3-4). Reaction at the site of injection was observed in 5 patients, causing treatment discontinuation in 2 cases. Other non-haematological toxicities were moderate. These results suggest acceptable toxicity and some antitumour activity of vinorelbine in pretreated SCLC patients. 相似文献
1000.
R Azarian F Lofaso F Zerah H Lorino G Atlan D Isabey A Harf 《Canadian Metallurgical Quarterly》1993,6(4):552-558
Pressure support (PS), a new mode of ventilatory assistance, is known to induce respiratory muscle relaxation. It was used to obtain reliable measurements of the compliance of the respiratory system (Crs) in awake subjects. PS was applied, through a mouthpiece, at four successive levels (0, 0.75, 1 and 1.25 kPa) to 30 healthy subjects. At the highest PS level, the subject's relaxation was obtained as assessed by a decrease in the occlusion pressure from 0.10 +/- 0.06 to 0.05 +/- 0.04 kPa, whereas the minute ventilation increased (from 7.5 +/- 1.5 to 13.8 +/- 3.3 l.min-1), and the end-tidal carbon dioxide tension (PCO2) decreased (from 5.0 +/- 0.4 to 3.2 +/- 0.5 kPa) below its apnoea threshold. In three subjects, respiratory muscle relaxation was confirmed by a fall in diaphragmatic electromyographic activity. Crs was calculated as the ratio of the tidal volume to the corresponding end-inspiratory airway pressure (i.e. PS level) since, at end inspiration, a zero-flow period was obtained. Crs was highly correlated (r = 0.77) to the height (Ht) of the subjects: Crs (l.kPa-1) = 3.56 x Ht (m) -4.86 (+/- 0.23), allowing normal values to be determined. In order to evaluate the applicability of the method to patients, Crs was measured in four patients with scoliosis, and was found to range from 45-82% of the predicted values. It is suggested that this simple method of Crs determination may be used to characterize various chest wall or pulmonary diseases. 相似文献