共查询到20条相似文献，搜索用时 31 毫秒
1.
Bernard D. Steinberg 《Journal of The Franklin Institute》1979,307(3):205-206
The theory of transient operations of synchronous machines—the so called two-reaction theory—was developed during the years 1926–1938. Doherty, Nickle and Park made the first efforts to find a complete theory. The problem then was solved by Kron for a general rotating electrical machine. In this paper the two-axis-model-machine is described using a bond graph. An example is given in which state-space-equations and output-equations are derived from the bond graph. A power-conserving transformation between the electrical quantities of the armature windings of the model machine and those of the real three phase armature windings is developed. This transformation is shown as a displacement modulated transformer structure which is central to the bond graph model. 相似文献
2.
This article investigates the ways in which the reporting of technological developments in artificial intelligence (AI) can serve as occasions in which Occidental modernity's cultural antinomies are played out. It takes as its reference point the two chess tournaments (in 1996 and 1997) between the then world champion Gary Kasparov and the IBM dedicated chess computers Deep Blue and Deeper Blue and shows how these games of chess came to be seen as an arena where fundamental issues pertaining to human identity were contested. The article considers the dominant framing of these encounters in terms of a conflict between two opposed categories—“human” and “machine”—and argues the essential role of human agency, the human supplement, in the performances of machine intelligence. 相似文献
3.
《Information processing & management》2019,56(2):274-290
In this paper we focus on the problem of question ranking in community question answering (cQA) forums in Arabic. We address the task with machine learning algorithms using advanced Arabic text representations. The latter are obtained by applying tree kernels to constituency parse trees combined with textual similarities, including word embeddings. Our two main contributions are: (i) an Arabic language processing pipeline based on UIMA—from segmentation to constituency parsing—built on top of Farasa, a state-of-the-art Arabic language processing toolkit; and (ii) the application of long short-term memory neural networks to identify the best text fragments in questions to be used in our tree-kernel-based ranker. Our thorough experimentation on a recently released cQA dataset shows that the Arabic linguistic processing provided by Farasa produces strong results and that neural networks combined with tree kernels further boost the performance in terms of both efficiency and accuracy. Our approach also enables an implicit comparison between different processing pipelines as our tests on Farasa and Stanford parsers demonstrate. 相似文献
4.
Fabio Fossa 《Ethics and Information Technology》2018,20(2):115-126
The aim of this paper is to offer an analysis of the notion of artificial moral agent (AMA) and of its impact on human beings’ self-understanding as moral agents. Firstly, I introduce the topic by presenting what I call the Continuity Approach. Its main claim holds that AMAs and human moral agents exhibit no significant qualitative difference and, therefore, should be considered homogeneous entities. Secondly, I focus on the consequences this approach leads to. In order to do this I take into consideration the work of Bostrom and Dietrich, who have radically assumed this viewpoint and thoroughly explored its implications. Thirdly, I present an alternative approach to AMAs—the Discontinuity Approach—which underscores an essential difference between human moral agents and AMAs by tackling the matter from another angle. In this section I concentrate on the work of Johnson and Bryson and I highlight the link between their claims and Heidegger’s and Jonas’s suggestions concerning the relationship between human beings and technological products. In conclusion I argue that, although the Continuity Approach turns out to be a necessary postulate to the machine ethics project, the Discontinuity Approach highlights a relevant distinction between AMAs and human moral agents. On this account, the Discontinuity Approach generates a clearer understanding of what AMAs are, of how we should face the moral issues they pose, and, finally, of the difference that separates machine ethics from moral philosophy. 相似文献
5.
本系统充分利用FX1N系列晶体管输出PLC的Y0和Y1的高速脉冲序列输出功能,配合两组伺服电机作为两轴定位,根据中频感应快速加热的优点,设计实现了稳定、高速、精确的尼龙涂敷自动化系统。 相似文献
6.
樊阳程 《科学技术与辩证法》2011,(6):32-36
西蒙对归纳问题的思考始于科学发现逻辑的探讨。最初,他试图将归纳法排除在科学发现逻辑之外,但未获成功。在以机器发现方法研究科学发现逻辑的过程中,西蒙在归纳问题上发生了表征转变,将归纳法合理性的辩护从逻辑角度转到认知视角上来。基于批判现代经验论的温和自然主义立场,西蒙从归纳的似然性和人类认知理性的有限性两个方面抛弃了归纳合理性逻辑辩护的认识论传统,提供了归纳问题的认知解答。 相似文献
7.
通过运用科学和哲学的思维,借助归纳法、逻辑推理法和内容分析法,对《数字时代情报学理论与实践——从信息服务走向知识服务》进行分析。通过对主标题关键字进行分类,借助基本的数理统计知识,对著作各章的主标题关键字进行了词频统计分析,确定了著作的核心知识领域。最终将《数字时代情报学理论与实践——从信息服务走向知识服务》一书的评价结果与业界共享。 相似文献
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Citizens as consumers: Profiling e-government services’ users in Egypt via data mining techniques 总被引：1，自引：0，他引：1
This study uses data mining techniques to examine the effect of various demographic, cognitive and psychographic factors on Egyptian citizens’ use of e-government services. Data mining uses a broad family of computationally intensive methods that include decision trees, neural networks, rule induction, machine learning and graphic visualization. Three artificial neural network models (multi-layer perceptron neural network [MLP], probabilistic neural network [PNN] and self-organizing maps neural network [SOM]) and three machine learning techniques (classification and regression trees [CART], multivariate adaptive regression splines [MARS], and support vector machines [SVM]) are compared to a standard statistical method (linear discriminant analysis [LDA]). The variable sets considered are sex, age, educational level, e-government services perceived usefulness, ease of use, compatibility, subjective norms, trust, civic mindedness, and attitudes. The study shows how it is possible to identify various dimensions of e-government services usage behavior by uncovering complex patterns in the dataset, and also shows the classification abilities of data mining techniques. 相似文献
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《Information processing & management》2023,60(3):103262
Smart wheelchairs based on brain–computer interface (BCI) have been widely utilized recently to address certain mobility problems for people with disability. In this paper, we present SmartRolling, an intuitive human–machine interaction approach for the direct control of robotic wheelchair that jointly leverages EEG signals and motion sensing techniques. Specifically, SmartRolling offers two wheelchair-actuation modes for users with different physical conditions: (1) head motion only — people who are severely disabled but able to do basic tasks using eyes and head, and (2) head and hands motion — in addition to type 1, people who can use functioning hands/arms for extra tasks. The system issues operation commands by recognizing different EEG patterns elicited by motor execution (ME) tasks including eye blink, jaw clench, and fist open/close, while at the same time estimates users’ steering intentions based on their facing direction by leveraging inertial measurements and computer vision techniques. The experiment results demonstrate that the proposed system is robust and effective to meets the individual’s needs and has great potential to promote better health. 相似文献
13.
Hamdi Echeikh Ramzi Trabelsi Atif Iqbal Med Faouzi Mimouni 《Journal of The Franklin Institute》2018,355(5):2112-2141
High performance multiphase motor drive requires precise knowledge of the state quantities and the machine parameters. Access to these state quantities is through measurement using sensors whose accuracy is paramount to achieve the performance level required by industrial applications. However, the problems of the parameters variations, inaccessibility to the measurement of some states, no-observability of the machine in some regions, the cost of the sensors and their lack of precision, make this very difficult task. To address these problems, it is necessary to resort to soft sensors through the design of observers and estimators. In multiphase induction motor drive, the observation problem arises especially for rotor flux that is not accessible for measurement. About the parameters variations, the rotor resistance and the stator resistance are the most critical parameters of the machine because their influence is crucial for the control and observation. The change in the resistances can be as large as 40–50% of the rated value, which may affect the control adversely. This paper develops a new structure of an adaptive sliding mode observer based on an online estimation of the rotor resistance value in order to avoid the effect of its variation in the rotor flux oriented control. The results show convergent (the errors in the transient and steady states are 5% and 1%, respectively) behavior of the drive using the proposed control scheme for large rotor resistance variation under loaded condition. The stability of the drive is proved using Lyapunov criteria. The simulation results are validated using real time implementation. 相似文献
14.
The use of immersive technologies has changed the consumption environment in which retailers provide services. We present findings from a study designed to investigate consumer responses toward a $17 million AI-embedded mixed reality (MR) exhibit in a retail/entertainment complex which combines advanced technology entertainment with retail shopping. Findings from our study demonstrate that the quality of AI (i.e., speech recognition and synthesis via machine learning) associated with an augmented object increases MR immersion associated with spatial immersion, MR enjoyment, and consumers’ perceptions of novel experiences. Collectively, these increase consumer engagement, and positively influence behavioral responses—specifically, purchase intentions and intentions to share experiences with social groups. Overall, findings from this study show that interactive AI and MR technology open new avenues to promote consumer engagement. 相似文献
15.
Joachim Gretz 《Endeavour》1982,6(1):34-39
Because of the sheer magnitude—ten thousand times greater than the world's present power requirements—solar energy has long seemed an attractive alternative to conventional sources of power. As this appraisal—based on the world's first helioelectric power plant, in Italy—makes clear, however, there are major problems in the generation of solar energy in Europe, especially in northern parts. A more feasible alternative may be for installations to be established in Third World countries—with abundant space and intense sunshine—and the energy exported in the form of an energy-rich fuel such as hydrogen. 相似文献
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Angiopteris sparsisora Ching, sp. nov.
Species nova ab omnibus affinibus adhuc cognitis recedit rhizomate repente, dorsi-
ventrali, habitu minore stipite tenui, levi, paleis brunneis lineari-lanceolatis margine
irregulariter fimbriatis peltati-fixis, pinnulis basi cuneatis vel late cuneatis, distincte
breviterque petiolulatis, soris longitudine variis, inter se separatis a margine magis re-
motis, paraphysibus rudimentalibus brevibus sparse praesentibus.
Tota planta 1—1.2 m alata, rhizomate repente, carnoso, cylindrico, dorsiventrali, 5—
6 cm diametro, radicoso, apice frondes 2—3 emittente, stipite 35—70 cm longo, 4—8 mm
crasso, levi viridi, supra medium uni-geniculato (in frondibus pinnatis usque subbipin-
natis), paleis brunneis lineari-lanceolatis basi rotunda peltati-fixis margine varie fimb-
riatis sparse vestito; lamina stipite longiore, bipinnata aut subb ipinnata raro superne
simpliciter pinnata; pinnis 2—3(—7)-jugis, ,alternis vel suboppositis, oblongis, 45—
55 cm longis, 18—23 cm latis, petiolo 4—16 cm longo suffultis, basi tumidis, pinnatis vel
interdum simplicibus vel basi pinnatifidis; pinnulis plerumque 8—12-jugis, alternis vel
suboppositis, patentibus, 8—18 cm longis, medio 1.5—3cm latis, lanceolatis, acuminatis,
basin versus cuneatis vel late cuneatis, breviter petiolatis, pinnula terminali confomi
paulo majore, petiolulata, hasi baud in alas decurrente, margine serrulatis; venis utrin-
quo distinctis, patentibus, simplicibus vel furcatis, prope marginem curvatis; pagina
frondis textura in sicco virescente, chartacea, rachi, costis, costulis venisque subtus
sparsim minuteque paleaceis. Soris breviter linearibus, 2—4 mm longis, 10—32-spo-
rangiatis, inter se separatis, a margine 2—3 mm, remotis; paraphysibus sparsis brevibusrudimentalibus. Sporis globulosis, suparficie dense tubuculatis.
Yunnan austro-orientalis: Xichou Xian, Fadou, S. K. Wu 4203 (typus, PE), 4198,
8, October, 1962; ibidem, Z. R. Wang 566-1, 566-2, 566-3, 566-4, 566-5, 15, January,
1978; ibidem V. M. Chu 8212, 15, January, 1978. in valley under evergreen broad-
leaved forests, alt. 1500—1550m.
In the tropical rain forest in southeastern Yunnan, China, the members of Angiopte-
ris Hoffm. and Archangiopteris Christ et Gies. are often growing side by side in great
abundance. In January 1978 the second writer made a botantical trip there and col-
lected in one locality ample herbarium material of an Angiopteris, which is identical
with A. sparsisora Ching (ined.), based upon type specimens gathered by Mr. S. K. Wu
from the same locality in 1962. To our great surprise, however, this distinct taxon
reveals a number of important morphological characteristics intermediate between An-
giopteris and Archangiopteris as diagnosed above.
The present species resembles Archangiopteris in small build with creeping dorsi-
ventral rhizome, unigeniculate, thin, smooth stipe in pinnate to bipinnatifid fronds, spa-
ringly clad in linear-lanceolate peltately affixed scales with variously fimbriate margin,
lamina 1—2 pinnate or subbipinnate, pinnules distinctly and shortly stipitate, base
cuneate or broadly cuneate, sori of different length separated from each other by broad
spaces, and rather far away (2—3 mm) from the margin, paraphyses few, rudimentary
and short, but, on the other hand, it also similar to Angiopteris in usually bipinnate
fronds, the petiole of pinnae with swollen base (blackish upon drying), short (2—4 mm
long) linear sori consisting of 5—16 pairs of sporangia and globulax spores with densely
tubucular sporoderms. All the above characteristics combined clearly indicate the spe-
cies is in all likelihood a natural hybrid between Angiopteris and Archangiopteris,
pending cytological investigation and the reason for presently placing it in Angiopteris
rather than in Archangiopteris is because of the fact that in overall impression the newtaxon appears more like the former than the latter. 相似文献
18.
19.
以生态遗传学成种理论和技术进化论为理论依据,研究现代生物技术的形成和进化路径,一方面可以为技术的形成和演变增加研究角度,另一方面,也可从影响物种形成的因素分析过程中探寻生物技术演化的内在机理,为促进现代生物技术研究和发展,培育现代生物技术产业提供指导和借鉴。类比物种形成和成种机理,研究了现代生物技术所具有的拓展、派生和驱动等物种特性,总结了现代生物技术的形成机理和四种典型演化路径(,i)选择——渐进性创新过程中的技术自我强化;(ii)重组——技术的嫁接或融合;(iii)突变——产生于突破性创新的间断性技术;(iv)迁徙——现有技术应用到新领域。 相似文献
20.
李承森 《中国科学院研究生院学报》1982,20(3):331-342
A new psilophytic plant, Hsüa robusta, is found in the Xujiachong Formation
(Emsian) of the Lower Devonian from the Qüjing (= Kütsing) district of Yunnan,
China. This plant is tentatively referred to the Cooksoniaceae of Rhyniales.
Hsüa gen. nov.
Type species: Hsüa robusta (Li et Cai) C. S. Li.
Diagnosis: Plants erect and then creeping. Main axes dividing pseudomonopodial-
ly and bearing dichotomous lateral branches which somewhat differentiate into vegeta,
tire and fertile ones, with dichotomous root-like and rhizophore-like appendages. Spo-
rangia terminal, round to reniform or wide reniform, dehiscing along distal margin into
two equal halves. Spores homosporous, trilete. Stomata anomocytic. Protostele cen-
trarch.
Hsüia robusta (Li et Cai) C. S. Li, comb. nov.
Cooksonia zhanyiensis Li et Cai, Acta Geologica Sinica, 52 (1) 1978, p. 10, pl. II,
fig. 6.——Taeniocrada robusta Li et Cai,ib. p. 10, pl. II, fig. 7—14.
Diagnosis: Characters same as in generic diagnosis. Main axes 6—10 mm wide and
at least 24 cm long, with vascular strands 1.2—2.4 mm acr oss. Fertile branches 3—4
times equally or unequally dichotomous, 10—1.5 mm in width and up to 11 cm in length,
possessing a vascular bundle of 0.5 mm in its greatest diameter. Branches circinately
coiled in apical regions. Axial tubercles, root-like and rhizophore— like appendages aris-
ing from the main axes usually anterior to the lateral branches. Axial tubercle round
with a diameter of 2.2—2.4 mm, having a vascular bundle about l mm across. Root-
like branches 3 times bifurcate, 1—0.3 mm wide and up to 1.5 cm long, with a vascular
bundle about 0.1 mm across. Rhizophore-like appendages forked, 3—1.7 mm in width,
possessing a vascular bundle of 0.7 mm in its greatest diameter. Root-like protuberances
sometimes arising from rhilzophore-like branches. Epidermal cells of axes generally
elongate, measuring 60—290μby 25—60 μ. Stomata mainly fusiform, 90—110 μ long
and 50—60μ wide, consisting of a pair of guard cells enclosing a pore 6—15μ in length
and 1—3μ in width. Cuticle of guard cells quite thick. Stomatal density about 5 per
mm2. Sporangia 0.8—4.2 mm high, 1.0—8.2 mm across, usually having a dehiscent distal
border which measures 50—100μ broad. Demarcation between sporangium and its stalk
quite clear. Epidermal cells of basal part of sporangial walls elongate, about 100 μ long
and 30μ wide, but those of distal part isodiametrally polygonal, about 50μ in diame-
ter. Stomata, radially arranged scattering over sporangial walls, generally round about
50μ in diameter and 50 per sporangium. Spores round, 18—36μ (average 27μ) indiameter, and smooth. Tracheids of protoxylem about 10μ across; those of metaxylem
about 30μ across, with scalariform thickening.
This plant is similar to Renalia hueberi Gensel in general morphology, but differs
from the latter in possessing root-like and rhizophore-like branches.
The generic name is derived from Prof. Hsü Jen. This paper is a thesis for M. Sc. 相似文献