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51.
Two experiments examined the disruption of feature-based selection in triple-conjunction search at multiple target transfers. In Experiment 1, after 10 training sessions, a new target possessing previous distractor features was introduced. This produced disruption in RT and fixation number, but no disruption in feature-based selection. Specifically, there was a tendency to fixate objects sharing the target's contrast polarity and shape and this did not change even upon transfer to the new target. In Experiment 2, 30 training sessions were provided with three target transfers. At the first transfer, the results replicated Experiment 1. Subsequent transfers did not produce disruption on any measure. These findings are discussed in terms of strength theory, Guided Search, rule-based approaches to perceptual learning, and the area activation model. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
52.
In a change detection paradigm, a target object in a natural scene either rotated in depth, was replaced by another object token, or remained the same. Change detection performance was reliably higher when a target postcue allowed participants to restrict retrieval and comparison processes to the target object (Experiment 1). Change detection performance remained excellent when the target object was not attended at change (Experiment 2) and when a concurrent verbal working memory load minimized the possibility of verbal encoding. (Experiment 3). Together, these data demonstrate that visual representations accumulate in memory from attended objects as the eyes and attention are oriented within a scene and that change blindness derives, at least in part, from retrieval and comparison failure. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
53.
In Part 1 of this two-part series, we introduced Katamic memory—a neural network architecture capable of robust sequence learning and recognition. In Part 2, we introduce the Blobs World taskjdomain for language learning and describe the DETE language learning system, which is composed of over 50 Katamic memory modules. DETE currently learns small subsets of English and Spanish via association with perceptual! motor inputs. In addition to Kaiamic memory, DETE employs several other novel features: (1) use of feature planes, to encode visual shapes, spatial relationships and the motions of objects, (2) phase-locking of neural firing, in order to represent focus of atention and to bind objects across multiple feature planes, and (3) a method for encoding temporal relationships, so that DETE can learn utterances involving the immediate past and future. We compare DETE to related models and discuss the implications of this approach for language-learning research.  相似文献   
54.
The purpose of this study is to investigate the precipitation characteristics of σ phase in the fusion zone of stainless steel welds at various welding passes during a tungsten are welding (GTAW) process. The morphology, quantity, and chemical composition of the δ-ferrite and σ phase were analyzed using optical microscopy (OM), a ferritscope (FS), a X-ray diffractometer (XRD), scanning electron microscopy (SEM), an electron probe micro-analyzer (EPMA), and a wavelength dispersive spectrometer (WDS), respectively. Massive δ-ferrite was observed in the fusion zone of the first pass welds during welding of dissimilar stainless steels. The σ phase precipitated at the inner δ-ferrite particles and decreased δ-ferrite content during the third pass welding. The σ and δ phases can be stabilized by Si element, which promoted the phase transformation of σ→ϱ+λ2 in the fusion zone of the third pass welds. It was found that the σ phase was a Fe−Cr−Si intermetallic compound found in the fusion zone of the third pass welds during multi-pass welding.  相似文献   
55.
矫直状态下钢管弹塑性变形区的研究   总被引:2,自引:0,他引:2  
李强 《钢管》1995,(4):34-37
根据钢管矫直时的变形规律,通过对矫直中钢管的力学状态及矫直前后的状态参数分析,建立了一种适于现场应用的确定钢管弹、塑性变形区的新方法。  相似文献   
56.
全断面双护盾掘进机在引黄工程断层破碎带的卡机处理   总被引:1,自引:0,他引:1  
万家寨引黄工程国际Ⅱ、Ⅲ标已查明的断层有34条,隐伏断层可能还有一些,除了利民堡区域性大断层(F32)外,较大的集中于7#洞北段59+700—68+820,主要有F65、F70、F90、F74。全断面双护盾掘进机适应于较复杂的地质条件,因此在通过断层破碎带时一般都较正常。但在通过引黄工程区域性大断层F65时,发生了卡机事故,处理用了3个月时间。该文对处理TBM卡机事故的施工进行了总结。  相似文献   
57.
周秋珍 《节能》2005,(3):10-11,20
介绍了标准型直燃机的分类、原理及长庆至呼和浩特输气管道工程冷冻供热站的设计实例 ,重点论述了标准型直燃机在严寒地区使用的利弊  相似文献   
58.
Probabilistic Visual Cryptography Schemes   总被引:1,自引:0,他引:1  
  相似文献   
59.
In this paper we present a new radiosity algorithm, based on the notion of a well distributed ray set (WDRS). A WDRS is a set of rays, connecting mutually visible points and patches, that forms an approximate representation of the radiosity operator and the radiosity distribution. We propose an algorithm that constructs an optimal WDRS for a given accuracy and mesh. The construction is based on discrete importance sampling as in previously proposed stochastic radiosity algorithms, and on quasi Monte Carlo sampling. Quasi Monte Carlo sampling leads to faster convergence rates and the fact that the sampling is deterministic makes it possible to represent the well distributed ray set very efficiently in computer memory. Like previously proposed stochastic radiosity algorithms, the new algorithm is well suited for computing the radiance distribution in very complex diffuse scenes, when it is not feasible to explicitly compute and store form factors as in classical radiosity algorithms. Experiments show that the new algorithm is often more efficient than previously proposed Monte Carlo radiosity algorithms by half an order of magnitude and more.  相似文献   
60.
渤海湾盆地复式油气聚集带高勘探程度区进一步挖潜的领域   总被引:15,自引:4,他引:11  
渤海湾盆地复式油气聚集区经过了40年的勘探,目前已进入了高勘探程度区.油气聚集的复杂规律表明,渤海湾盆地仍具有巨大的资源潜力,进一步挖潜的领域非常广阔.以第三系为烃源岩的含油气层系的勘探精度仍有待于进一步提高,同时必须将以古生界、中生界和中上元古界为烃源岩的含油气层系作为今后挖潜的重要领域.渤海湾盆地任何层系都可能形成和聚集油气,因此仍有多种复杂的油气藏类型尚待进一步认识和发现.  相似文献   
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