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991.
The aim of this paper is to gain better understanding of the way map users read and interpret the visual stimuli presented to them and how this can be influenced. In particular, the difference between expert and novice map users is considered. In a user study, the participants studied four screen maps which had been manipulated to introduce deviations. The eye movements of 24 expert and novice participants were tracked, recorded, and analyzed (both visually and statistically) based on a grid of Areas of Interest. These visual analyses are essential for studying the spatial dimension of maps to identify problems in design. In this research, we used visualization of eye movement metrics (fixation count and duration) in a 2D and 3D grid and a statistical comparison of the grid cells. The results show that the users’ eye movements clearly reflect the main elements on the map. The users’ attentive behavior is influenced by deviating colors, as their attention is drawn to it. This could also influence the users’ interpretation process. Both user groups encountered difficulties when trying to interpret and store map objects that were mirrored. Insights into how different types of map users read and interpret map content are essential in this fast-evolving era of digital cartographic products.  相似文献   
992.
Produced over the past decade, monuments and museums dedicated to the Civil Rights movement of the 1950s and 1960s have desegregated America's memorial landscape. Tracing a broad arc across the US South, the material elements of this landscape — historic markers, monuments, parks, registered buildings, and museums — present a distinct challenge to representations of an elite, white American past. This challenge, however, is offered in a distinctly gendered manner, inasmuch as the role of women in organizing and leading the movement is obscured. Further, the historical narratives concretized at these sites are mediated by conventions associated with civil rights historiography and the tourism development industry. The result is a complex, sometimes ironic landscape. Via the narratives they embed and the crowds they attract, these landscapes are co-constitutive with contemporary politics of representing the past in the United States. This paper offers an overview of current memorial practices and representations of the Civil Rights movement found at the country's major memorial landscapes.  相似文献   
993.
This article describes a novel approach for finding similar trajectories, using trajectory segmentation based on movement parameters (MPs) such as speed, acceleration, or direction. First, a segmentation technique is applied to decompose trajectories into a set of segments with homogeneous characteristics with respect to a particular MP. Each segment is assigned to a movement parameter class (MPC), representing the behavior of the MP. Accordingly, the segmentation procedure transforms a trajectory to a sequence of class labels, that is, a symbolic representation. A modified version of edit distance called normalized weighted edit distance (NWED) is introduced as a similarity measure between different sequences. As an application, we demonstrate how the method can be employed to cluster trajectories. The performance of the approach is assessed in two case studies using real movement datasets from two different application domains, namely, North Atlantic Hurricane trajectories and GPS tracks of couriers in London. Three different experiments have been conducted that respond to different facets of the proposed techniques and that compare our NWED measure to a related method.  相似文献   
994.
995.
在分析黑山煤田区域构造背景和勘查资料的基础上,论述了构造运动对煤层赋存的控制作用,并以三种控煤构造组合形式揭示了本区的基本赋煤规律。聚煤期同沉积构造控制着含煤性在空间上的变化;印支期NWW向褶皱对煤层的赋存起着关键的控制作用;喜山晚期张性和走滑断层,破坏了煤层的连续性,并控制了煤田东、西部残留煤系的埋藏深度。逆冲——褶皱和断裂——单斜式控煤构造组合中,逆断层上盘煤层抬升而利于勘查开采,但规模有限;褶皱——断裂式控煤构造组合中,复式向斜之次级背斜区,煤系上覆地层受剥蚀,煤层埋藏较浅,为主要的有利勘查区。  相似文献   
996.
海岸阶地的形成是海平面变动、地壳变动或两者共同作用之结果.研究海阶不仅可印证推论古气候、往昔海平面变化及地壳变动状况,更可藉以了解各区域间变动的差异,全盘了解大地构造的意义,同时,小规模的海阶变动,常与地震活动伴生,研究海阶可作为判读地震周期的依据之一,所以,世界各地位于地壳活动带的国家对于海阶的形态与演育过程均作详细的调查及研究.位于台湾海峡北部两侧的台湾西北部以及马祖、金门等海岸地区,都有海阶的分布.透过阶地分布、地形特征与阶序对比,同时,利用世界海阶对比基图找出该地区的地壳隆升率与海阶可能形成的年代,并藉以了解各区域间变动的差异.前述地区的海阶大致上可分成高位与低位2群,高位海阶分布的高度在15~275m之间,上覆红壤层,为晚更新世时期产物;低位海阶分布的范围较小,高度较矮,大部分分布于海滩与高位阶地末端阶崖问,沿着海岸呈带状分布,阶面大多无红壤层覆盖,海拔在10m以下.组成的物质多以砾石及砂为主,属于全新世时期的产物,即近1万年以来全球高海水位时期(第四纪最后一次冰期结束后)所形成.利用海阶对比基图与已有的定年数据,辅以地形地貌及堆积物特征比较,获得各段阶地之平均隆升率,台湾西北部之观音山北部沿海、客雅溪口南岸、后龙溪口南岸3个地区,分别是2.1mm/a、2.2mm/a、2.15mm/a,数值相近,显示该区之地盘隆升率及海平面变动状况大致相同;仅新竹山子顶沿海地盘隆升率较小,为1.4mm/a.此表示,台湾岛的海阶变化不仅受到海平面变动的影响,尚受到区域性地壳隆升的控制.马祖与金门地区的隆升率则分别为1.6mm/a、1.3mm/a,由于该区仅受新华夏断裂构造的控制,因此,其活动的幅度相对而言较台湾为小.  相似文献   
997.
We used Argos‐linked Fastloc‐Global Positioning System (Argos‐linked Fastloc‐GPS) satellite tags to investigate how loggerhead sea turtles use neritic foraging habitats at multiple scales. Out of 24 turtles, six individuals used more than one foraging site, with all sites being separated by >25 km. These six individuals used up to four sites, remaining at each site for a mean of 150 days and returning to the same site a minimum of 52 days later. The other 18 turtles remained in a single site. The area within sites was not used uniformly, with 15 out of 24 turtles exhibiting complex movement patterns within and amongst up to five focal patches, which were typically 0.1–5.0 km apart within a single site. Movements between sites and patches might sometimes have reflected overwintering behaviour; however, similar movement patterns occurred at multiple times of the year, suggesting other factors were also involved. Use of multiple sites and patches might be driven by differences in resource availability, such as food and/or night‐time refuges, competition, or exploratory movement to investigate or locate alternative patches. We confirmed competition via direct visual observations of aggressive interactions between individuals at one foraging patch. Our results illustrate the importance of standardizing data to the same number of locations per day and night to accurately delineate key areas used by turtles or for evidence‐based marine protected area planning.  相似文献   
998.
COSMO-SkyMed is a constellation of four X-band high-resolution radar satellites with a minimum revisit period of 12 hours. These satellites can obtain ascending and descending synthetic aperture radar (SAR) images with very similar periods for use in the three-dimensional (3D) inversion of glacier velocities. In this paper, based on ascending and descending COSMO-SkyMed data acquired at nearly the same time, the surface velocity of the Yiga Glacier, located in the Jiali County, Tibet, China, is estimated in four directions using an offset tracking technique during the periods of 16 January to 3 February 2017 and 1 February to 19 February 2017. Through the geometrical relationships between the measurements and the SAR images, the least square method is used to retrieve the 3D components of the glacier surface velocity in the eastward, northward and upward directions. The results show that applying the offset tracking technique to COSMO-SkyMed images can be used to derive the true 3D velocity of a glacier’s surface. During the two periods, the Yiga Glacier had a stable velocity, and the maximum surface velocity, 2.4?m/d, was observed in the middle portion of the glacier, which corresponds to the location of the steepest slope.  相似文献   
999.
Shang Gao  Zheng N. Fang 《水文研究》2019,33(21):2729-2744
A synthetic storm generator—Dynamic Moving Storm (DMS)—is developed in this study to represent spatio‐temporal variabilities of rainfall and storm movement in synthetic storms. Using an urban watershed as the testbed, the authors investigate the hydrologic responses to the DMS parameters and their interactions. In order to reveal the complex nature of rainfall–run‐off processes, previously simplified assumptions are relaxed in this study regarding (a) temporal variability of rainfall intensity and (b) time‐invariant flow velocity in channel routing. The results of this study demonstrate the significant contribution of storm moving velocity to the variation of peak discharge based on a global sensitivity analysis. Furthermore, a pairwise sensitivity analysis is conducted to elucidate not only the patterns in individual contributions from parameters to hydrologic responses but also their interactions with storm moving velocity. The intricacies of peak discharges resulting from sensitivity analyses are then dissected into independent hydrologic metrics, that is, run‐off volume and standard deviation of run‐off timings, for deeper insights. It is confirmed that peak discharge is increased when storms travel downstream along the main channel at the speed that corresponds to a temporal superposition of run‐off. Spatial concentration of catchment rainfall is found to be a critical linkage through which characteristics of moving storms affect peak discharges. In addition, altering peak timing of rainfall intensity in conjunction with storm movement results in varied storm core locations in the channel network, which further changes the flow attenuation effects from channel routing. For future directions, the DMS generator will be embedded in a stochastic modelling framework and applied in rainfall/flow frequency analysis.  相似文献   
1000.
提出一种利用半参数模型对REHSM和RELSM两种弹性模型进行精化的方法,对中国大陆构造环境监测网络在环渤海区域的近几期GPS速度场进行拟合分析。结果表明,本文方法具有更高的拟合精度,增强了模型解释能力。  相似文献   
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