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1.
In the cultural heritage area, it is of fundamental importance to characterize and classify the conservation state of the materials constituting ancient monuments, in order to study and monitor their decay. Generally, the decay diagnosis is provided by “naked eye” analysis done by expert scientists “walking around” the artifact and recording the conservation state of each individual element they observe. In this paper, a color image segmentation approach, based on histogram threshold and edge detection techniques is presented, to extract degradation regions, characterized by holes or cavities, from color images of stone-materials. The goal is to provide an aid to the decay diagnosis by segmenting degraded regions from color images, computing quantitative data, such as the area and perimeter of the extracted zones, and processing qualitative information, such as various levels of depth detected into the same zones. Since color is a powerful tool in the distinction between objects, a segmentation technique based on color, instead of intensity only, has been used to provide a clearer discrimination between regions. The study case concerns the impressive remains of the Roman Theatre in the city of Aosta (Italy). In particular, we have processed and analyzed some color images of the theatre puddingstones, acquired by a camera.  相似文献   
2.
试验选取三类不同熟期的春小麦品种(品系),在同一时间倒伏后,分期对比测定各品种(品系)倒伏后不同发育阶段的籽粒鲜重、干重,比较分析品种(品系)倒伏与未倒伏籽粒的灌浆特性及干物质积累变化规律。结果表明:倒伏对不同品种(品系)籽粒干物质积累动态变化的差异显著性影响不同,对同一品种(品系)的最大灌浆速率及到达最大灌浆速率的时间均存在着影响,最终对籽粒产量存在着不同程度的影响。  相似文献   
3.
研究以乙醇胺、氯化氢和二氯亚砜为原料,以氯仿做溶剂,合成2-氯乙胺盐酸盐.实验表明:在气态氯化氢的存在下,摩尔比为1:1.04的乙醇胺和二氯亚砜在71℃下反应4小时, 可获取产率98%的2-氯乙胺盐酸盐.  相似文献   
4.
EMDR是一个整合性的、以咨客为中心的心理治疗方法,它着重于大脑的信息加工系统、烦扰经历的记忆,这些病理学基础不是由器质性的损伤导致的。EMDR强调对临床情境有作用的经历,和那些需要带领咨客达到更健康的心理状态的经历。EMDR作为以经验为主的支持治疗,本文综述其历史、发展和研究,在阐述适应性信息加工模型之后,用一个延续的个案实例来说明了EMDR的个案概念化和8个阶段的治疗。这个方法用于加工那些建立病理学基础的和触发当前功能失调的早期记忆,并为将来恰当的行为提供模板,包括克服技能和(或)发展性的不足所需的知识与行为。整合的EMDR与家庭系统观点的好处是可以提供最综合的治疗效果。  相似文献   
5.
Infrared (IR) absorption spectra and X-ray powder diffraction (XRD) patterrns of sexpenfine cat's eye from Sichuan Province have been investigated, and infrared absorption bands of the serpentine have been assigned in this paper. The results indicate that the bands near 3 600 - 3 700 cm^-1 belong to the stretching absorption band VOH, the bands in 948 - 1 100 cm^-1 axe assigned to the stretching vibraling band Usvo, and the bands at 600 570 and 440 cm^-1 respectively belong to the bending vibration band VOH, δMg-O and δSi-O. The serpentine cat' s eye includes two types: chrysotile and antigorite. Chrysotile has a sharp and intensive band at 3 688 cm^-1 and a weak band at 3 643 cm^-1 , while antigorite has only one intensive band in the region. At vibration band VSi-O, chrysotile and antigorite have a similar feature at 1 071 cm^-1, but the band at 980 cm^-1 in anfigorite has been split into two bands in chrysotile - a strong one at 1 027 cm^-1 and a weak one at 949 cm^-1. In addition, antigorite has a characteristic bending vibrating band δMg-O at 570 cm^-1. Based on the analysis of the feature of crystal structure, their IR differences axe well explained.  相似文献   
6.
Abstract

A “look-up line” (LUL) has been proposed for ice hockey, which is an orange 1?m (40′) warning line (WL) painted on the ice at the base of the boards. The LUL purports to provide an early warning to players to keep their head up prior to and as they are being checked. We determined if players looked up more on a rink with the LUL compared to a traditional Control rink. Elite offensive (O) and defensive (D) players competed 1 vs. 1, while wearing an eye tracker that recorded their quiet eye (QE) and fixation and tracking (F-T) and an electrogoniometer that measured head angle. External cameras recorded skate duration during four skate phases: P1 preparation, P2 decision-making, P3 cut to boards, P4 contact. The QE was the final fixation prior to contact between O and D as they skated towards and across the WL during P3 and P4. Skate phase durations (%) did not differ by rink or rink by position. More QE and F-T occurred on the WL on the LUL rink than on the Control. The expected increase in head angle on the LUL rink did not occur during P3 or P4. Post-hoc results also showed O and D skated further from the boards on the LUL rink, suggesting the players preferred to control the puck on white ice, rather than the orange colour of the LUL rink. More research is needed to determine if these results apply to the competitive setting.  相似文献   
7.
眼动的速度最高可达到600°/s,具有比人手更灵敏的反应,因此有更好的实时性和应激性,通过眼动识别可以准确反映人体的动作特征,实现动作的判断和预测。采用眼动识别的图像处理算法实现对乒乓球运动员的动作预测,提高攻球效能,改进乒乓球攻击和防御的目的性。传统方法中对乒乓球运动员的眼动识别算法采用边缘特征融合算法,对运动员的动作变换跟踪性能不好,提出一种基于多模态融合眼动识别的乒乓球运动员动作预测算法。提取边缘特征,进行虹膜定位设计,统计搜索区域灰度直方图分布,建立虹膜颜色与边缘联合特征模板,通过多模态融合眼动时变分析,采用从粗到细的处理方法,在减少匹配对应项的同时进行动作预测相关系数匹配,预测跟踪目标中心,实现动作预测,仿真结果表明,算法对运动员的动作预测准确度高,实现对乒乓球运动员动作的实时跟踪和识别。  相似文献   
8.
This study investigated whether anticipation and search strategies of goalkeepers are influenced by temporally and spatially manipulated video of a penalty. Participants were clustered into three groups depending on skill: goalkeepers (n = 17), field players (n = 20) and control group (n = 20). An eye tracker was worn whilst watching 40 videos of a striker kicking to four corners of a goal in random order. All 40 videos were temporally occluded at foot-to-ball contact, and the non-kicking leg of 20 videos was spatially manipulated. Results showed that goalkeepers had significantly better predictions than the two groups with no differences between the two testing conditions. According to effect size, the percentage of fixation location and viewing time of the kicking leg and ball were greater for the goalkeepers and field players group than the control group irrespective of testing conditions. The fixations on the kicking leg and ball in conjunction with comparable predictions between spatially manipulated and control conditions suggest that goalkeepers may not rely on the non-kicking leg. Furthermore, goalkeepers appear to use a global perceptual approach by anchoring on a distal fixation point/s of the penalty taker whilst using peripheral vision to obtain additional information.  相似文献   
9.
线上藏品不同的图文布局方式会影响观众的注意过程,进而影响观众对相应图文信息的获取效果。本文通过眼动实验,研究了观众浏览藏品页面文物图片与说明文字时上图下文、上文下图、左图右文、左文右图四种页面布局方式对观众注意行为的影响,同时关注了四种形式下观众对页面中所包含的文物大小、形制、纹饰、工艺、历史文化意义等多项信息的获取情况,从而探究线上藏品图文布局对观众信息获取的影响,进而为线上藏品页面的设置提供借鉴,使其更好地以观众的注意特点为导向促进藏品信息的传播。  相似文献   
10.
国内外的相关研究表明,眼动研究可以通过对数学问题解决过程中的眼动轨迹进行记录以及对注视时间、注视次数等眼动指标的分析,进而了解数学问题解决过程中,大脑的内部加工机制。数学学科能力主要体现为数学问题的解决能力,通过数学学科教育中的眼动研究文献分析发现,眼动研究有助于探寻数学问题解决过程中注意分配及加工策略选择过程。在数学学科教育中针对这些认知加工的特点进行策略教学旨在:培养高效的注意能力、提取关键的表征信息、激发多知识体系的想象力,更好地提高学科教育的有效性。  相似文献   
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