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61.
62.
如何优化医疗设施空间分布,最大限度利用医疗卫生资源、保障医疗服务公平性和可及性是政府卫生管理部门经常遇到的难题。地理信息系统技术在医疗设施空间布局研究中得到广泛的应用。基于地理信息系统的医疗设施空间分布研究方法主要包括基于地理学空间相互作用理论的区位分析模型方法、基于运筹学规划技术的区位——配置模型方法和优势度模型方法。 相似文献
63.
介绍内蒙古医科大学临床信息多媒体导航系统的设计方法及主要功能,总结其应用效果。该系统可以有效防止护理疏忽和差错的出现,简化工作程序,提高工作效率,降低沟通成本。 相似文献
64.
Sridhar Ravi Tim Siesenop Olivier Bertrand Liang Li Charlotte Doussot William H. Warren Stacey A. Combes Martin Egelhaaf 《Proceedings of the National Academy of Sciences of the United States of America》2020,117(49):31494
Animals that move through complex habitats must frequently contend with obstacles in their path. Humans and other highly cognitive vertebrates avoid collisions by perceiving the relationship between the layout of their surroundings and the properties of their own body profile and action capacity. It is unknown whether insects, which have much smaller brains, possess such abilities. We used bumblebees, which vary widely in body size and regularly forage in dense vegetation, to investigate whether flying insects consider their own size when interacting with their surroundings. Bumblebees trained to fly in a tunnel were sporadically presented with an obstructing wall containing a gap that varied in width. Bees successfully flew through narrow gaps, even those that were much smaller than their wingspans, by first performing lateral scanning (side-to-side flights) to visually assess the aperture. Bees then reoriented their in-flight posture (i.e., yaw or heading angle) while passing through, minimizing their projected frontal width and mitigating collisions; in extreme cases, bees flew entirely sideways through the gap. Both the time that bees spent scanning during their approach and the extent to which they reoriented themselves to pass through the gap were determined not by the absolute size of the gap, but by the size of the gap relative to each bee’s own wingspan. Our findings suggest that, similar to humans and other vertebrates, flying bumblebees perceive the affordance of their surroundings relative their body size and form to navigate safely through complex environments.Avoiding collisions with obstacles is a requirement for successful locomotion through most natural habitats, where the physical environment is often cluttered and complex. At the most elemental level, animals moving through their environments need to identify gaps between obstacles and assess their passability. In this context, whether a gap between obstacles “affords” passing is determined by the fit between the spatial layout of the environment and the properties of the organism’s form and action system, as described in classical theses on affordances (1–3). In humans and other highly cognitive vertebrates, the perception of affordances for performing visually guided actions such as grasping, passing through apertures, and climbing is actively shaped throughout ontogeny, as body size, configuration, and experience change (2, 4–7). However, the strategies used by animals with much smaller brains, such as insects, to contend with the challenges of navigating environmental clutter and spatial heterogeneity are unclear.We used bumblebees to investigate whether flying insects take into account their own size during interactions with their surroundings. Bumblebees and other volant insects that travel long distances (8) and frequently encounter regions of dense clutter can be expected to exhibit strategies to avoid collisions, because damage to sensitive structures such as the wings is irreparable and adversely impacts flight performance and lifespan (9, 10). For an animal attempting to navigate through tight spaces, perceiving the relationship between the layout of the environment and its own size can help inform the animal of its potential for collision-free passage. Bumblebee workers naturally display large variation in body size within a given colony (11, 12), and thus are particularly suitable models for testing the effects of insect body size on aerial navigation and for determining whether insects perceive the external environment in relation to their own spatial dimensions.To elicit repeatable flight behavior, we trained foraging bumblebees to fly within a 1.6 × 0.3 × 0.3 m (l × w × h) flight tunnel that separated the hive from a foraging arena (Materials and Methods, SI Appendix, Fig. S1, and Movie S1). After bees were habituated to the setup and began foraging normally, we placed an unexpected obstacle within the tunnel, consisting of a thin vertical wall (5-mm thickness) spanning the tunnel’s width and height. The obstructing wall contained a rectangular gap starting midway up and extending to the top of the wall (Materials and Methods, SI Appendix, Fig. S1, and Movie S1). The width of the gap was varied between 20 and 60 mm over different trials, with the presenting order of gap sizes chosen randomly. A high-speed camera placed above the tunnel was used to record bees’ instantaneous positions, heading/yaw orientations (Fig. 1A), and trajectories as they approached the obstructing wall and passed through the gap. To prevent bees from becoming familiar with the experimental paradigm, the obstructing wall was removed after each flight recording. In total, we recorded and analyzed over 400 flights of bees of varying body sizes flying through seven different gap sizes (SI Appendix, Table S1). For the population of bees recorded, wingspan was the longest dimension of the body and it varied linearly by a factor of 1.9 compared to their longitudinal body length while in flight (SI Appendix, Fig. S2A).Open in a separate windowFig. 1.Bumblebees can safely fly through gaps that are smaller than their wingspan. (A and B) Illustrations indicating the wingspan of bees (Ws), the size of the gap (Gs), and the positive and negative yaw (heading) angles for bees flying in the tunnel, respectively. (C) Schematic illustration of the flight of a bee flying through a gap that is much wider than its wingspan. (D) The instantaneous yaw angle of bee shown in C. (E) Schematic illustrationof the flightofabeeflying through a gap that is smaller than its wingspan. (F) The instantaneous yaw angle of bee shown in E. Flights, in both cases (C and E), consisted of approach, lateral peering, and—for the smaller gap size (E)—body reorientation (an increase in yaw angle) while passing through the gap. The differences in reorientation behavior can be noted at x = 0 (location of the gap), whereas in F the bee displays a large increase in yaw angle that reorients its body to pass through the small gap, and body reorientation in D is minimal. For the flight shown in C and D, Ws = 27.5 mm and Gs = 50 mm, while for the flight shown in E and F, Ws = 27 mm and Gs = 25 mm. 相似文献
65.
Katharine N. Thakkar 《Cognitive neuropsychiatry》2013,18(5):477-500
Introduction. Adopting another person's visuospatial perspective has been associated with empathy, which involves adopting the psychological perspective of another individual. Both reduced empathy and abnormal visuospatial processing have been observed in those with schizophrenia and schizophrenia-related personality traits. In the current study, we sought to explore the relationship between empathy, schizotypy, and visuospatial transformation ability. Methods. 32 subjects (16 women) performed a visuospatial perspective-taking task and a mental letter rotation task. Response times and accuracy were analysed in relation to dimensions of self-reported empathy, indexed using the Interpersonal Reactivity Index, and schizotypy, as measured by the Schizotypal Personality Questionnaire. Results. We found that: (1) greater cognitive and affective empathy were associated with reduced negative schizotypy, and, in men, greater cognitive empathy was associated with reduced positive schizotypy; (2) improved accuracy for imagined self–other transformations in the perspective-taking task was associated with greater self-reported cognitive empathy in women and higher positive schizotypy across genders; (3) faster mental letter rotation was associated with reduced cognitive empathy and increased negative schizotypy in women. Conclusions. Together, the findings partially support the commonalities in visuospatial transformation ability, empathy, and schizotypy, and posit an interesting link between spatial manipulations of our internal representations and interactions with the physical world. 相似文献
66.
《International journal of oral and maxillofacial surgery》2020,49(12):1640-1647
Zygomatic fibrous dysplasia is a slowly progressive disorder of bone, which commonly causes facial asymmetry. Precise surgical recontouring can effectively improve facial aesthetics. The aim of this study was to quantitatively evaluate the effectiveness of surgical navigation guidance in correcting zygomatic asymmetry. The study included 26 patients with unilateral zygomatic fibrous dysplasia who underwent bony recontouring. They were divided into two groups according to the use of intraoperative surgical navigation (navigation group and conventional group; n = 13 in each group). Clinical outcomes were evaluated using three-dimensional computed tomography. Six pairs of landmarks were identified, and the coordinates were used to calculate asymmetry indices. The curvature of protruding regions in the surgical area was measured to determine facial skeletal symmetry in three dimensions. The results were compared between the groups. All patients recovered uneventfully and their facial symmetry and aesthetics improved. For three of the six pairs of landmarks, symmetry was better in the navigation group than in the conventional group (all P ≤ 0.02). The postoperative curvature ratios were better (more symmetrical) in the navigation group (P = 0.01). Surgical navigation enhances postoperative facial symmetry. However, the clinical significance of this enhancement when compared to conventional non-navigation surgery needs further investigation. 相似文献
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68.
A New Asymmetric Directional Microphone Algorithm With Automatic Mode‐Switching Ability for Binaural Hearing Support Devices 下载免费PDF全文
Jinryoul Kim Kyoung Won Nam Sunhyun Yook Dong Pyo Jang In Young Kim Sung Hwa Hong 《Artificial organs》2015,39(6):535-540
For hearing support devices, it is important to minimize the negative effect of ambient noises for speech recognition but also, at the same time, supply natural ambient sounds to the hearing‐impaired person. However, conventional fixed bilateral asymmetric directional microphone (DM) algorithms cannot perform in such a way when the DM‐mode device and a dominant noise (DN) source are placed on the same lateral hemisphere. In this study, a new binaural asymmetric DM algorithm that can overcome the defects of conventional algorithms is proposed. The proposed algorithm can estimate the position of a specific DN in the 90°–270° range and switch directional‐ and omnidirectional‐mode devices automatically if the DM‐mode device and the DN are placed in opposite lateral hemispheres. Computer simulation and KEMAR mannequin recording tests demonstrated that the performance of the conventional algorithm deteriorated when the DM‐mode device and the DN were placed in the opposite hemisphere; in contrast, the performance of the proposed algorithm was consistently maintained regardless of directional variations in the DN. Based on these experimental results, the proposed algorithm may be able to improve speech quality and intelligibility for hearing‐impaired persons who have similar degrees of hearing impairment in both ears. 相似文献
69.
There has long been interest in why languages are shaped the way they are, and in the relationship between sign language and gesture. In sign languages, entity classifiers are handshapes that encode how objects move, how they are located relative to one another, and how multiple objects of the same type are distributed in space. Previous studies have shown that hearing adults who are asked to use only manual gestures to describe how objects move in space will use gestures that bear some similarities to classifiers. We investigated how accurately hearing adults, who had been learning British Sign Language (BSL) for 1–3 years, produce and comprehend classifiers in (static) locative and distributive constructions. In a production task, learners of BSL knew that they could use their hands to represent objects, but they had difficulty choosing the same, conventionalized, handshapes as native signers. They were, however, highly accurate at encoding location and orientation information. Learners therefore show the same pattern found in sign-naïve gesturers. In contrast, handshape, orientation, and location were comprehended with equal (high) accuracy, and testing a group of sign-naïve adults showed that they too were able to understand classifiers with higher than chance accuracy. We conclude that adult learners of BSL bring their visuo-spatial knowledge and gestural abilities to the tasks of understanding and producing constructions that contain entity classifiers. We speculate that investigating the time course of adult sign language acquisition might shed light on how gesture became (and, indeed, becomes) conventionalized during the genesis of sign languages. 相似文献
70.