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991.
住宅输电线是世界上分布最广泛的网络,无处不在的家庭电源插座即将成为人们进入互联网世界的大门,期盼通过电线,将PC、电话、音响甚至电冰箱都能连成一气,统统连上网络,彼此沟通,而无需大费周折另外布线!要完全不出错,通过电源线进行讯号处理的复杂程度远远超过之前采用的任何技术. 相似文献
992.
993.
994.
W.D. Reekie 《Research Policy》1973,2(3):246-264
In this paper the patenting activity of the international pharmaceutical industry in London between 1900 and 1966 is analysed. Although patent data as a measure of industrial activity is not without defects it can be used both as an adjunct to and as a surrogate for more conventional yardsticks such as concentration ratios, sales statistics and so on. The results indicate that patenting activity can be used as both an absolute and relative indicator of an industry's pace of technological change. They help pinpoint the international distribution of pharmaceutical research and development. If analysed by product or process they can aid in the understanding of why an industry's competitive behaviour is or is not primarily one of price rivalry. Finally, they illustrate the continuing role of the individual inventor. 相似文献
995.
996.
The decade of the 1970s heralded a major research effort into mariculture of economically important red and brown seaweeds. Limited and declining natural populations, lack of synthetic substitutes for the phycocolloids, and their upwardly spiralling costs have emphasized the need for more research in this area. Algal mariculture is now technically and scientifically feasible, but the economic realities are still undetermined. This article examines what is known about seaweed mariculture and discusses where future research efforts must go. 相似文献
997.
998.
Artificial Life (ALife) has two goals. One attempts to describe fundamental qualities of living systems through agent based
computer models. And the second studies whether or not we can artificially create living things in computational mediums that
can be realized either, virtually in software, or through biotechnology. The study of ALife has recently branched into two
further subdivisions, one is “dry” ALife, which is the study of living systems “in silico” through the use of computer simulations,
and the other is “wet” ALife that uses biological material to realize what has only been simulated on computers, effectively
wet ALife uses biological material as a kind of computer. This is challenging to the field of computer ethics as it points
towards a future in which computer and bioethics might have shared concerns. The emerging studies into wet ALife are likely
to provide strong empirical evidence for ALife’s most challenging hypothesis: that life is a certain set of computable functions
that can be duplicated in any medium. I believe this will propel ALife into the midst of the mother of all cultural battles
that has been gathering around the emergence of biotechnology. Philosophers need to pay close attention to this debate and
can serve a vital role in clarifying and resolving the dispute. But even if ALife is merely a computer modeling technique
that sheds light on living systems, it still has a number of significant ethical implications such as its use in the modeling
of moral and ethical systems, as well as in the creation of artificial moral agents. 相似文献
999.
A performance index consisting of a Chebyshev absolute maximum functional plus terminal and integral cost is applied to the optimal control of dynamical systems. First-order necessary conditions are derived for a large class of systems. Utilizing the necessary conditions, analytic examples are worked in demonstrating many of the properties of this class of systems. 相似文献
1000.
Maddy and Mathematics: Naturalism or Not 总被引:1,自引:0,他引:1
Penelope Maddy advances a purportedly naturalistic account ofmathematical methodology which might be taken to answer thequestion `What justifies axioms of set theory?' I argue thather account fails both to adequately answer this question andto be naturalistic. Further, the way in which it fails to answerthe question deprives it of an analog to one of the chief attractionsof naturalism. Naturalism is attractive to naturalists andnonnaturalists alike because it explains the reliability ofscientific practice. Maddy's account, on the other hand, appearsto be unable to similarly explain the reliability of mathematicalpractice without violating one of its central tenets.
- 1 Introduction
- 2 Mathematical Naturalism
- 3 Desiderata and the attractionof naturalism
- 4 Assessment: Naturalism and names
- 4.1 Takingnaturalismseriously
- 4.2 Second philosophy (orwhat's in a name)
- 5 A way out?
- 6 Or out of the way?
- 2 Mathematical Naturalism