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21.
The authors used visual search tasks in which components of the classic flanker task (B. A. Eriksen & C. W. Eriksen, 1974) were introduced. In several experiments the authors obtained evidence of parallel search for a target among distractor elements. Therefore, 2-stage models of visual search predict no effect of the identity of those distractors. However, clear compatibility effects of the distractors were obtained: Responses were faster when the distractors were compatible with the response than when they were incompatible. These results show that even in parallel search tasks identity information is extracted from the distractors. In addition, alternative interpretations of the results in terms of the occasional identification of a distractor before or after the target was identified could be ruled out. The results showed that flat search slopes obtained in visual search experiments provide no benchmark for preattentive processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
22.
Jan Buijs 《Creativity & Innovation Management》2007,16(2):203-210
Innovating is a multi‐faceted process. In this paper, four different, yet intertwined aspects of this process are distinguished. The first aspect concerns the content of the innovation; a new product, a new technology or a new market. The second aspect concerns the group dynamics of the innovation team. The third aspect concerns seeing the innovation process as a creative process. And the fourth aspect has to do with leadership. Since these four aspects are simultaneously working together during the innovation process, the leaders of this process are working in a very difficult situation, as all four aspects need to be dealt with in different ways. Nearly all of them are, in one way or another, in conflict with one another. They may conflict in real actions, in time horizons (past, present or future) or in effect (positive reactions during market introduction do not garantee ultimate market success). This means that innovation leaders need to show a special kind of leadership. This leadership must be balanced, people‐focused and must include a high tolerance for ambiguity and paradoxes. They have to be nice and nasty at the same time. In short: innovation leaders should be some kind of controlled schizophrenics. 相似文献
23.
Jan‐Chan Huang 《应用聚合物科学杂志》2003,90(3):671-680
A modified method is discussed that is based on Farooque and Deshpande's method to obtain polymer–polymer interaction parameters using inverse gas chromatography (IGC) data. In the Farooque and Deshpande method, the ratio of the difference of probe–polymer interaction parameters between two polymers and the probe volume [(χ12 ? χ13)/V1] is used as the abscissa. In the modified method, the ratio [(?2χ12 + ?3χ13)/V1] is used as the abscissa. Experimental data previously reported for a poly(?‐caprolactone)‐polyepichlorohydrin (PCL/PECH) blend and a poly(ethyl acrylate)‐poly(vinyl propionate) (PEA/PVPr) blend are analyzed. It is found that the slopes obtained by the new method had smaller deviations from the theoretical values than the Farooque and Deshpande method. The standard deviations of both slopes and intercepts obtained from the new method are also smaller. Using the new method, the polymer–polymer interaction parameters obtained from the intercept are negative numbers for the PCL/PECH system and very small positive numbers for PEA/PVPr. Explanations are given for the probe and concentration dependency of the polymer–polymer interaction parameters that are generally observed in IGC studies. A new method for selecting the best probe for calculating the interaction parameter is discussed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 671–680, 2003 相似文献
24.
Jan Lindblad 《电子设计技术》2004,11(10):58-64
即使在系统中事实上仍然有许多空闲内存时,内存碎片还会最终导致出现内存用完的情况.一个不断产生内存碎片的系统,不管产生的内存碎片多么小,只要时间足够长,就会将内存用完. 相似文献
25.
Victor Chabanenko Roman Puźniak Adam Nabiałek Sergei Vasiliev Vladimir Rusakov Loh Huanqian Ritta Szymczak Henryk Szymczak Jan Jun Janusz Karpiński Vitaly Finkel 《Journal of Low Temperature Physics》2003,130(3-4):175-191
We present a study of magneto-thermal instabilities in polycrystalline MgB2 superconductor, by magnetic hysteresis loop measurements and by investigations of magnetic flux dynamics with a miniature Hall probe. Temperature and magnetic field ranges where the flux jumps may be observed have been determined. On the basis of measurements of the magnetic flux dynamics, an average magnetic diffusivity describing the process of the flux jump is estimated. This parameter is compared with the thermal and magnetic diffusivities calculated on the basis of available data for thermal conductivity, heat capacity and resistivity. It is shown that the estimated value of the field of the first flux jump is influenced significantly by the field dependence of specific heat. In order to explain the observed phenomenon, the temperature reached by the sample during the flux jump at different magnetic fields is calculated. 相似文献
26.
The paper discusses normative systems and their revision within an algebraic framework. If a system is logically well-formed, certain norms, called connecting norms, determine the system as a whole. It is maintained that, if the system is well-formed, a relation “at least as low as” determines a lattice or quasi-lattice of its connecting norms. The ideas are presented mainly in the form of comments on a legal example concerning acquisition of movable property by extinction of another person's previous rights. 相似文献
27.
Summary A derivation of a parallel algorithm for rank order filtering is presented. Both derivation and result differ from earlier designs: the derivations are less complicated and the result allows a number of different implementations. The same derivation is used to design a collection of priority queues. Both filters and priority queues are highly efficient: they have constant response time and small latency.
Anne Kaldewaij received an M.Sc. degree in Mathematics from the University of Utrecht (The Netherlands) and a Ph.D. degree in Computing Science from the Eindhoven University of Technology. Currently, he is associate professor in Computing Science at Eindhoven University. His research includes parallel programming and the design of algorithms and data structures. He enjoys teaching and he has written a number of textbooks on mathematics and programming.
Jan Tijmen Udding received an M.Sc. degree in Mathematics in 1980 and a Ph.D. degree in Computing Science in 1984 from Eindhoven University of Technology. Currently, he is associate professor at Groningen University. His main research interests are mathematical aspects of VLSI, program derivation and correctness, and functional programming. 相似文献
28.
New CAMAC based data acquisition and beam control system for Lund nuclear microprobe 总被引:1,自引:0,他引:1
Mikael Elfman Per Kristiansson Klas Malmqvist Jan Pallon Anders Sjland Rogerio Utui Changyi Yang 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1997,130(1-4):123-126
A new CAMAC based data acquisition system has been installed at the Lund Nuclear Microprobe facility. This paper reports on the development and present status of the data acquisition system. The system is a true multiparameter CAMAC based system with fast Fera bus readout and in crate memory buffer. The user interface is based on Sparrow Kmax software for a Power Macintosh platform. The system read out and tag the event data with position on-line, which make fast on-line monitoring of spectra or element maps possible.Simultaneously, all data can be saved event by event for off-line analysis. The beam scanning part is software controlled through a timed D/A converter, this allows fast scanning of the beam. With a CCD-camera and video card the area to be analysed could be defined directly from the image, and the sample position can be moved. Any kind of irregular scan patterns could be defined. 相似文献
29.
Structure-activity studies of human tumour necrosis factors 总被引:3,自引:0,他引:3
Van Ostade Xaveer; Tavernier Jan; Fiers Walter 《Protein engineering, design & selection : PEDS》1994,7(1):5-12
The mechanism by which tumour necrosis factors (TNF and lymphotoxin,also called TNFß and TNFß respectively) exerttheir cytotoxic activity on many malignant cells, remains largelyunknown. Furthermore, the broad array of differentiation (geneinduction) and mitogenic activities towards many primary cellsis still a subject of intensive investigation. TNF is an importantmediator in inflammation, immune responses and infection-relatedphenomena and these activities contribute to the severe toxidtyseen when TNF is used as an anticancer agent. The first stepin the mechanism of action is the specific binding of the ligandto its receptors and dissection of the molecular mechanism involvedin this interaction is the subject of this review. The reasonsfor the interest in this aspect are obvious: first, the developmentof strong antagonistic TNF analogues can be useful in dampeningthe potentially lethal or debilitating effects of an overproductionof the cytokine (as in septic shock or rheumatoid arthritis).Secondly, since two distinct TNF receptors exist, constructionof TNF muteins that distinguish between both types may leadto derivatives of this plekrtropic agent with a more restrictedbiological activity pattern. Ideally, one would like to developa TNF mutant that has retained its cytotoxic action on tumourcells without inducing the deleterious systemic toxteity. Suchan optimized TNF molecule could become a potent anticancer agent 相似文献
30.
热等静压技术的发展及应用 总被引:9,自引:1,他引:8
在介绍热等静压技术和设备发展的基础上,对其在提高铸件质量以及拓展高速钢、双炼钢和超级双炼钢、高性能陶瓷等新型材料应用领域方面的作用,进行了较全面的阐述。并预计,因热等静压技术所具有的优势,在今后几年其应用增长可达到每年递增15%-20%的水平,且随着其在铝加工工艺中应用的拓展,年增长率可望达到25%。 相似文献