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41.
A wide-range strain sensor which utilizes optical fiber as the transducing element is reported. This device differs from the well-known microbend type sensor in that a roller chain is used to impose constant curvature bends on the fiber, rather than a corrugated plate which imposes sinusoidal bends in the microbend sensors. This change also leads to a wide range of sensitivity adjustment and a linear calibration curve. 相似文献
42.
36 left-handed and 36 right-handed kindergarten children were asked to print after seeing a series of reversible letters and numbers presented individually on slides or flash cards. Regardless of handedness, both groups of Ss found the left–right orientation cues of the same letters and numbers difficult to recall. This challenges a proposal expressed in the "grammar of action" that claims that certain reversal errors in children's printing result from the inappropriate application of the horizontal motor rule, because although left- and right-handed children use this rule, they do so in different ways and therefore should have produced different errors. Another sample of 86 right-handed children from nursery school through Grade 1 was given the same printing task. Findings from this 2nd sample provide an additional challenge to the grammar of action by showing that reversals of the letter N, which are also thought to result from a misapplication of motor rules, decrease in frequency along with reversals of other letters and numbers, instead of increasing as predicted, during the developmental period when the motor rules that are said to be responsible for reversals of this particular letter become more strongly established. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
H Kaufmann 《Canadian Metallurgical Quarterly》1976,94(13):756-760
In the treatment of breast cancer a radiation therapy is indicated under the following conditions: 1. Postoperative irradiation only of the regional lymph-nodes also in stage I (T1, N0). 2. Postoperative irradiation of the regional lymph-nodes and the thorax wall in cases with great primary tumours (T2), in cases with involved axillary lymph-nodes and, of course, in all cases with "grave signs". 3. Preoperative irradiation only in those cases when it seems possible that an inoperable tumour would become operable. 4. As the sole local treatment only in cases with very large inoperable tumours or in special cases (e.g. very high risc or refusal of the operation). 5. As local treatment of a local recidive or of isolated metastases. 6. As supporting local therapy (e.g. threatening fracturation of our fracturated bone metastases; brain metastases) in cases of generalized metastatic disease treated by hormonal or cytostatic therapy. 相似文献
44.
C. el Dsoki V. Landersheim H. Kaufmann T. Bruder P. Krug T. Bohn C. Müller 《Materialwissenschaft und Werkstofftechnik》2006,37(12):1006-1017
The fatigue behaviour of spray compacted aluminium materials. Material properties for component design data: From specimen to component. Spray compacted, high performance aluminium alloys (DISPAL = DISpersion hardened Aluminium) are characterised by their high strength, high Young’s modulus, good wear resistance and low coefficient of thermal expansion. These properties vindicate both the application of these materials and the increasing interest of the automobile manufacturers. Within the framework of a bilateral project, tests were carried out by varying different parameters under both strain‐ and load‐controlled conditions in order to describe the fatigue behaviour of these materials. 相似文献
45.
Neil S. Grigg Marvin E. Criswell Darrell G. Fontane Thomas J. Siller 《Canadian Metallurgical Quarterly》2005,131(1):26-31
The fast-moving world of information technology confronts the civil engineer with constant change. This creates challenges for educators and students because rapid change requires curricula to be flexible and educators to gain competency and access to new equipment and software. Whereas a decade ago, civil engineering educators debated how to teach “programming,” the picture is now much more complex. The paper reports on how information technologies are changing the practice of civil engineering and offers a new framework for integrating next-generation information technology into the civil engineering curriculum at the department level. 相似文献
46.
Ledgerwood David M.; Steinberg Marvin A.; Wu Ran; Potenza Marc N. 《Canadian Metallurgical Quarterly》2005,19(2):175
Problem gamblers often attribute suicidal ideation or attempts to their gambling. Logistic regression analyses were applied to data from problem gamblers (N = 986) calling a helpline. Problem gamblers reporting gambling-related suicidality (n = 252; 25.6%) were more likely than those denying it (n = 734; 74.4%) to acknowledge family, financial, legal, and mental and substance-related problems. Of problem gamblers acknowledging gambling-related suicidality, those reporting gambling-related suicide attempts (n = 53; 21.5%) were more likely than those denying them (n = 193; 78.5%) to acknowledge gambling-related illegal behaviors, mental health and substance abuse treatment, and family histories of alcohol problems, and were less likely to report prior gambling treatment. The findings suggest that increased gambling severity is associated with gambling-related suicidality. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
47.
We consider the problem of routing packets on an MIMD mesh-connected array of processors augmented with row and column buses. We give lower bounds and randomized algorithms
for the problem of routing k-permutations (where each processor is the source and destination of exactly k packets) on a d-dimensional mesh with buses, which we call the (k,d)-routing problem.
We give a general class of ``hard' permutations which we use to prove lower bounds for the (k,d)-routing problem, for all k,d≥ 1. For the (1,1)- and (1,2)-routing problems the worst-case permutations from this class are identical to ones published by other authors, as are the
resulting lower bounds. However, we further show that the (1,d)-routing problem requires 0.72 ... n steps for d=3, 0.76 ... n steps for d=4, and slightly more than steps for all d≥ 5. We also obtain new lower bounds for the (k,d)-routing problem for k,d > 1, which improve on the bisection lower bound in some cases. These lower bounds hold for off-line routing as well.
We develop efficient algorithms for the (k,1)-routing problem and for the problem of routing k-randomizations (where each processor has k packets initially and each packet is routed to a random destination) on the one-dimensional mesh and use them in a general
(k,d)-routing algorithm which improves considerably on previous results. In particular, the routing time for the (1,d)-routing problem is bounded by steps with high probability (whp), whenever for some constant ε > 0, and the routing time for the (k,d)-routing problem is steps whp whenever for some constant ε > 0 and k≥ 3.6 ... d, matching the bisection lower bound.
We then present a simple algorithm for the (2,2)-routing problem running in 1.39 ... n+o(n) steps whp. Finally, for the important special case of routing permutations on two-dimensional meshes with buses, the (1,2)-routing problem, we give a more sophisticated algorithm that runs in 0.78 ... n+o(n) steps whp.
Received May 18, 1994; revised June 23, 1995. 相似文献
48.
C. M. Sonsino H. Kaufmann R. Masendorf A. Hatscher H. Zenner C.‐P. Bork J. Hinterdorfer H. M. Sonne B. Engl G. Steinbeck 《Materialwissenschaft und Werkstofftechnik》2004,35(8):522-533
Materials Data for Fatigue Life Calculation of Steel Sheet Structures for Automotive Engineering Within a joint project of the steel and automotive industry 17 steel sheet materials for automotive engineering in various delivery and forming conditions at temperatures of –40 °C, 22 °C and 100 °C were investigated. In the course of 37 test series strain controlled fatigue curves to crack initiation and stress‐strain‐curves under monotonic and cyclic loading were determined. All experimental data, hysteresis loops and determined cyclic properties are available in a database. A correlation between the mechanical properties from tensile tests and the properties from strain controlled cyclic experiments seems to be possible. 相似文献
49.
López Steven Regeser; Nelson Hipke Kathleen; Polo Antonio J.; Jenkins Janis H.; Karno Marvin; Vaughn Christine; Snyder Karen S. 《Canadian Metallurgical Quarterly》2004,113(3):428
The authors examined the role of family factors and the course of schizophrenia by carrying out additional assessments and analyses in 2 previously published studies of Mexican American and Anglo American patients and families. The authors found partial support for an attributional model of relapse for families who are low in emotional overinvolvement. Attributions of control, criticism, and warmth together marginally predicted relapse. The data also indicated that for Mexican Americans, family warmth is a significant protective factor, whereas for Anglo Americans, family criticism is a significant risk factor. These findings suggest that the sociocultural context shapes the pathways by which family processes are related to the course of illness. Moreover, the warmth findings suggest that families may contribute to preventing relapse. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
Based on the solidification theory for metal alloys, a simple recipe for the controlled processing of globular microstructures without external stirring is presented: Firstly, small solidification nuclei must be distributed homogeneously throughout a melt. In New Rheocasting (NRC) these nuclei are formed by forced homogeneous nucleation due to partial quenching of the melt, while in Super Rheocasting (SRC) the nuclei are “second phase particles” in specially designed alloys, which are grown in a controlled fashion in a certain temperature range. Potential alloy compositions for SRC are provided. Secondly, given these melts with small particles in them, globular growth can be assured by utilizing the Gibbs‐Thomson “self healing effect” and slow further cooling to allow diffusion in the melt and to suppress constitutional supercooling. This simple recipe is applicable to various ferrous and non‐ferrous alloys. If an SRC alloy is cooled more rapidly than necessary for globular growth of the primary phase, but is held sufficiently long in the SRC range for dispersoid formation, these dispersoids can act as potent grain refiners and possibly enhance elevated temperature properties. A combination of both processes by using SRC alloys in the NRC equipment may lead to pressure tight castings with low porosity and finer grain structure than can be achieved with NRC on its own, and consequently, better mechanical properties. 相似文献