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121.
The Software Engineering Initiative, process-improvement program undertaken by the Software Systems Laboratory in Raytheon's equipment division in mid-1988 is reviewed. The three phases of the program are the process-stabilization phase, in which the emphasis is on distilling the elements of the process actually being used and progressively institutionalizing it across all projects, the process-control phase, in which emphasis shifts to instrumenting projects to gather significant data and analyze the data to understand how to control the process, and the process-change phase, in which the emphasis is on determining how to adjust the process as a result of measurement analysis and how to diffuse the new methods among practitioners. It is shown that the process-improvement initiative has improved the equipment division's bottom line, increased productivity, and changed the corporate culture. Much of the savings came from reducing rework 相似文献
122.
Thomas Von Raumer Jean Michel Dion Luc Dugard 《International Journal of Adaptive Control and Signal Processing》1993,7(5):435-455
In this paper we present two adaptive non-linear speed control algorithms for induction motors. They employ input-output linearization techniques for the motor model in the stator fixed reference frame. The first control algorithm directly tracks speed and rotor flux. The second is designed using torque and rotor flux tracking and is extended for speed control. A key point is that this algorithm ensures exact current limitation in the known parameter case. The adaptation based on Lyapunov design can cope with rotor and stator resistance variations. Significant simulations using sampled controllers are presented emphasizing adaptation and current limitation effects. 相似文献
123.
124.
The survival of 119 colorectal cancer patients was analyzed in the light of the overexpression status of the c-myc proto-oncogene mRNA and the point mutation status of the p53 tumor suppressor gene in the primary adenocarcinoma. The presence of >3 fold overexpression of c-myc mRNA in the primary tumor was found to be associated with a better prognosis than patients who evinced no overexpression (P = 0.02, log rank analysis). Point mutation of the p53 tumor suppressor gene was found to be associated with a poorer patient prognosis (P = 0.007, log rank analysis). Endogenous levels of c-myc and point mutation of p53 both contributed independently toward a poorer patient prognosis in Cox regression modeling. The better prognosis seen in patients who overexpress c-myc was offset when c-myc overexpression was coupled with a point mutated p53 gene. These results suggest that in colorectal adenocarcinoma c-myc deregulation leads to increased apoptotic death, but that this response may be modulated by a more downstream event such as point mutation of the p53 gene. 相似文献
125.
Mann-Na Loong & Hwee-Kwang Goh 《International Journal of Food Science & Technology》2004,39(4):437-441
Mixed vegetable juice was acidified to a pH below 4 and subjected to pasteurization regimes between 80 and 100 °C. Hunter colour scale values (L, a and b) of the pasteurized samples were analysed to determine the kinetics of green and total colour degradation. The ‘a’ value was chosen as the physical parameter for green colour while ‘Lab’ represented the total colour. A concept, based on fractional conversion, was used for the determination of kinetic parameters. The results revealed that degradation of green and total colour of the acidified vegetable juice followed first‐order kinetics. Temperature dependency of the rate constants for both the green and the total colour could be described by the Arrhenius relationship. The activation energies of green and total colour degradation were 49.19 and 29.00 kJ mol?1, respectively. 相似文献
126.
Keelan J. Patrick R.; Dion Karen K.; Dion Kenneth L. 《Canadian Metallurgical Quarterly》1998,30(1):24
[Correction Notice: An erratum for this article was reported in Vol 30(2) of Canadian Journal of Behavioural Science/Revue canadienne des sciences du comportement (see record 2009-19933-001). Some figures were inadvertently omitted in two tables. The correct tables are provided in the erratum.] Explored a self-disclosure explanation for why those with a secure attachment style report greater relationship satisfaction than those with insecure attachment styles. Ss were 99 17–36 yr old students who were in ongoing relationships and who had different attachment styles. Ss were compared in terms of the self-disclosures they directed toward their partner vs a stranger, using questionnaire and behavioural measures. Behavioural self-disclosure was assessed by having Ss give talks on different topics, while anticipating that either their current partner or an opposite-sex stranger would later hear it. Results show that Ss with a secure attachment style disclosed more intimately to their partners than to strangers; whereas those with insecure attachment styles did not. Moreover, secures disclosed more personal facts to their partners than to strangers and were also perceived as more comfortable while self-disclosing to partners than to strangers. Finally, support for the hypothesis that self-disclosure mediates the relation between attachment style and relationship satisfaction was found on one component of self-disclosure, facilitative disclosure, a component which included both reported self-disclosure to one's partner and self-rated ability to elicit disclosure from others. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
127.
128.
Chee-Kiang Goh Yong-Ching Lim 《Signal Processing, IEEE Transactions on》1998,46(5):1426-1430
This correspondence presents an efficient algorithm for the design of M-channel cosine-modulated filter banks. Our algorithm needs only a few iterations to obtain a weighted minimax solution and provides flexible control of the ripples in the filter's stopband, the overall filter bank transfer function, and the aliasing components 相似文献
129.
Environmental stress screening (ESS) has been extensively used as a technique to improve electronic equipment reliability in the field by subjecting the equipment to temperature cycling, vibration and other environmental stresses during the manufacturing process. There are standards for ESS planning available. However, there are difficulties in establishing an optimum ESS regimen when using these standards for ESS planning. This paper intends to discuss these problems and at the same time, suggests a possible approach. The approach is illustrated by the development of an ESS program for a real life electronic system. The approach is especially suited for small-scale production for which opportunity for reiteration is reduced and hence, ESS has to be carefully designed from the beginning. 相似文献
130.
JB Nachega B Vandercam Y d''Udekem R Verhelst L Jacquet R Dion M Goenen 《Canadian Metallurgical Quarterly》1998,53(1):53-54
The production of mycotoxins by Alternaria alternata in cellulosic ceiling tiles was examined with thin-layer chromatography and high-performance liquid chromatography procedures. Alternariol and alternariol monomethyl ether were found in ceiling tile extracts, whereas extracts of control rice cultures of all three isolates produced these mycotoxins plus altenuene and altertoxin I. Extensive fungal growth and mycotoxin production occurred in the ceiling tiles at relative humidities of 84-89% and 97%. 相似文献