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排序方式: 共有5802条查询结果,搜索用时 31 毫秒
11.
Martin R?tteler 《Informatik - Forschung und Entwicklung》2006,55(3):3-20
Quantum algorithms are a field of growing interest within the theoretical computer science as
well as the physics community. Surprisingly, although the number of researchers working on the subject
is ever-increasing, the number of quantum algorithms found so far is quite small. In fact, the task of
designing new quantum algorithms has been proven to be extremely difficult. In this paper we give an overview
of the known quantum algorithms and briefly describe the underlying ideas. Roughly, the algorithms presented
are divided into hidden subgroup type algorithms and in amplitude amplification type algorithms. While
the former deal with problems of group-theoretical nature and have the promise to yield strong separations
of classical and quantum algorithms, the latter have been proved to be a prolific source of algorithms
in which a polynomial speed-up as compared to classical algorithms can be achieved. We also discuss
quantum algorithms which do not fall under these two categories and give a survey of techniques of
general interest in quantum computing such as adiabatic computing, lower bounds for quantum algorithms,
and quantum interactive proofs. 相似文献
12.
为了探讨跳高赛前控制训练这一课题,我们运用运动训练学的基本原理,采用随训跟踪的方法.对其进行了实验探讨,旨在摸索跳高赛前控制训练的一般规律,为青少年跳高的科学化训练积累经验。 相似文献
13.
Petra G?tte 《Zeitschrift für Erziehungswissenschaft》2006,17(33):129-137
Ohne Zusammenfassung 相似文献
14.
Zusammenfassung. Die automatische Erkennung und Lokalisation von Objekten in digitalen Bildern ist ein wesentlicher Bestandteil vieler praktisch
relevanter Anwendungen. In diesem Artikel wird ein erscheinungsbasiertes Verfahren zur Erkennung starrer zwei- oder dreidimensionaler
Objekte vorgestellt, dem eine statistische Modellierung zugrundeliegt. Im Gegensatz zu segmentierungsbasierten Verfahren,
wie sie vor allem im Bereich der 3D-Objekterkennung eingesetzt werden, erm?glicht der erscheinungsbasierte Ansatz aufgrund
der Modellierung der Intensit?tswerte oder davon abgeleiteter lokaler Merkmale eines Bildes die Erkennung komplexer Objekte.
Die statistische Formulierung der Problemstellung bildet den mathematischen Kontext zur Bestimmung optimaler L?sungen.
Die Form der Modellierung erlaubt neben der Einzelobjekterkennung auch die Berücksichtigung von heterogenem Bildhintergrund
und Mehrobjektszenen. Die dazu ben?tigten lokalen Merkmale entstehen durch r?umlich begrenzte Transformationen des Bildes,
wie beispielsweise Gabor- oder Wavelet-Transformationen. Die statistische Modellierung beschreibt die Verteilung dieser lokalen
Merkmale anhand einer Dichtefunktion, die sich bei der Hintergrund- und Mehrobjektmodellierung als Mischungsverteilung der
Einzelobjektverteilungen ergibt. Die Aufgabenstellungen des Erlernens und Erkennens von Objekten sind damit als Parametersch?tzprobleme
formal darstellbar. Dabei werden im einen Fall die Modellparameter und im anderen Fall die Lageparameter beziehungsweise die
Klassen von Objekten gesch?tzt. Die experimentelle überprüfung des Ansatzes anhand realer Objektaufnahmen durch CCD-Kameras
zeigt seine Brauchbarkeit zur Erkennung von 2D- und 3D-Objekten bei homogenem und heterogenem Hintergrund.
Eingegangen am 5. April 2000 / Angenommen am 20. Juli 2001 相似文献
15.
Donato Tamblé 《Archival Science》2001,1(1):83-100
Archival theory in Italy has a long tradition, going back as far as the second half of the nineteenth century, and with roots
in the 17th and 18th centuries. Central theme in the theory is themetodo storico, the principle of provenance, for the first time expressed in the late 19th century by Bonaini and Bongi. In the following
decades archivists like Casanova and Cencetti were among the leading authors. Elio Lodolini assigned himself the task to synthesize
ideas and notions, within a clear distinctions between records (registratura) and archives. One of the overall characteristics
of the rich Italian literature is the stressing of the cultural value of archives.
I have twice treated before the theme of archival theory in Italy from the fifties up to the nineties. The first time on the
occasion of the 25th anniversary of theScuola speciale per Archivisti e Bibliotecari dell'Università degli Studi “La Sapienza” di Roma in 1989, when there was an international round table on archival science in the State Archives of Rome. My essay,Italian archival science today, has been published in the proceedings of the meeting (cfr. Donato Tamblé,L'archivistica in Italia oggi, inStudi sull'archivistica, by Roma: Elio Lodolini, 1992). Some years later, in 1993, I published a book on contemporary Italian archival theory (Donato
Tamblé,La teoria archivistica italiana contemporanea (1950–1990). Profilo storico-critico (Roma, 1993) which was the sequel to the volume of Elio Lodolini on Italian archival history — (Lineamenti di storia dell'archivistica italiana (Roma, 1991). The purpose of my book was that of locating and identifying the scientific object of archival science as it
developed and was clarified in the thinking and in the lucubration of the contemporary Italian Archivists. 相似文献
16.
试论“网球肘”的成因、诊断、预防与治疗 总被引:2,自引:0,他引:2
“网球肘”是网球运动中常见的一种伤病。通过研究“网球肘”的成因、诊断、预防与治疗,预防伤病的发生。 相似文献
17.
Ta?eb Baccouche 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2002,7(2):217-228
This article describes an informal approach to human rights education, which is anchored in reality and based on experience gained throughout the Arab region and more particularly within the Arab Institute for Human Rights. It is argued that the approach of the Institute could be adopted on a larger scale by organisations working in this domain, not only in the Arab region but also in other regions of the world. The article emphasises the essential role of governments and the importance of cooperation between the governmental and non-governmental levels in order to implement this type of human rights education in informal learning situations, and thus to disseminate a universal culture of human rights. 相似文献
18.
19.
György Péteri 《Minerva》1996,34(4):367-380
Conclusions On the basis of these findings, I suggest that the structure and organisation of the field of Hungarian economics under state socialism should be described as a case of partitioned bureaucracy.9 The compromise between research economists and the political elite in the New Course era between 1953 and 195510 survived the post-1956 reaction in so far as political economy, with its predominantly legitimatory and ideological functions, remained partitioned from the other sectors in the field through the remainder of the state-socialist period. This secured considerable protection both for Marxist-Leninist political economy—which faced the destabilising effects of exposure to the findings of serious empirical research—and for the other sectors, which were professionally oriented and earnestly interested in the pursuit of unbiased empirical research, free from stifling agitprop interference. Our data concerning the reputational control of the field reflects only one, although very important, aspect of this partitioning. Another and much plainer aspect is that, from the early 1960s, the Agitation and Propaganda Department of the Central Committee no longer exercised control over the field, except in the political economy sector.The proposition about the mechanism paradigm should not be taken seriously as a statement of a Kuhnian type of intellectual organisation of Hungarian economics, with reform economics at its hard theoretical core. But it should certainly be taken seriously as a reflection of the sociopolitical structure which emerged and developed from the mid-1950s onwards. Neither the politicians nor the economists saw as necessary or even contemplated the integration of Hungarian economic research with Western mainstream economic thought. In exchange for the professional expertise and socio-economic intelligence necessary for the exercise of power, Hungary's state-socialist political class offered their economists relative autonomy and freedom from interference. The price the economists had to pay was partly to refrain from openly and systematically challenging the beliefs perpetuated by the political economy of socialism, and partly to accept in their research the paramountcy of policy orientation. But this burden they assumed willingly since it made them the only group within Hungary's academic intelligentsia—indeed, the only group in Hungarian society outside the political class—with the privilege of being coopted to the institutions with power over some restricted domains of policymaking. After 1989, especially under the conservative Antall government, this proved less than advantageous.11 Although the benevolence of many critics is open to question, it could greatly benefit the field if the economists' expulsion from contemporary politics went hand in hand with provision of the material, intellectual and institutional conditions for a new approach where a fundamentally scientific orientation is paramount. 相似文献
20.