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Recent Advances and Challenges of Visual Signal Quality Assessment 被引量:1
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作者 马林 邓宸伟 +1 位作者 颜庆义 林维斯 《China Communications》 SCIE CSCD 2013年第5期62-78,共17页
While quality assessment is essential for testing, optimizing, benchmarking, monitoring, and inspecting related systems and services, it also plays an essential role in the design of virtually all visual signal proces... While quality assessment is essential for testing, optimizing, benchmarking, monitoring, and inspecting related systems and services, it also plays an essential role in the design of virtually all visual signal processing and communication algorithms, as well as various related decision-making processes. In this paper, we first provide an overview of recently derived quality assessment approaches for traditional visual signals (i.e., 2D images/videos), with highlights for new trends (such as machine learning approaches). On the other hand, with the ongoing development of devices and multimedia services, newly emerged visual signals (e.g., mobile/3D videos) are becoming more and more popular. This work focuses on recent progresses of quality metrics, which have been reviewed for the newly emerged forms of visual signals, which include scalable and mobile videos, High Dynamic Range (HDR) images, image segmentation results, 3D images/videos, and retargeted images. 展开更多
关键词 objective quality assessment 2D images and videos human perception newly emerged visual signals Human Visual System
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The Exact Estimation of Visual Acuity by VEP Technology:A Report of 726 Cases of Eye Injury 被引量:3
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作者 饶广勋 吴炳为 张玲莉 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2010年第1期138-140,共3页
This study explored the accuracy of using visual evoked potentials(VEP)technology for visual acuity estimation.The enrolled 726 patients with post-traumatic unilateral decrease in visual acuity included the injured ey... This study explored the accuracy of using visual evoked potentials(VEP)technology for visual acuity estimation.The enrolled 726 patients with post-traumatic unilateral decrease in visual acuity included the injured eyes served as the experimental group,and the healthy eyes as the control group.The least signal visual angle(LSVA),and amplitude and latency of P100 were chosen as test indexes.The results under different experimental conditions were recorded by PRVEP technology.All data collected were processed... 展开更多
关键词 clinical forensic medicine visual evoked potentials visual acuity least signal visual angle amplitude and lateny of P100
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Colorful facial markings are associated with foraging rates and affiliative relationships in a wild group-living cichlid fish
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作者 Brett M.Culbert James B.Barnett +4 位作者 Isaac Y.Ligocki Matthew G.Salena Marian Y.L.Wong Ian M.Hamilton Sigal Balshine 《Current Zoology》 SCIE CAS CSCD 2024年第1期70-78,共9页
Many animals use color to signal their quality and/or behavioral motivations.Colorful signals have been well studied in the contexts of competi-tion and mate choice;however,the role of these signals in nonsexual,affil... Many animals use color to signal their quality and/or behavioral motivations.Colorful signals have been well studied in the contexts of competi-tion and mate choice;however,the role of these signals in nonsexual,affiliative relationships is not as well understood.Here,we used wild social groups of the cichlid fish Neolamprologus pulcher to investigate whether the size of a brightly colored facial patch was related to 1)individual quality,2)social dominance,and/or 3)affiliative relationships.Individuals with larger patches spent more time foraging and tended to perform more aggressive acts against conspecific territory intruders.We did not find any evidence that the size of these yellow patches was related to social rank or body size,but dominant males tended to have larger patches than dominant females.Additionally,patch size had a rank-specific relationship with the number of affiliative interactions that individuals engaged in.Dominant males with large patches received fewer affiliative acts from their groupmates compared to dominant males with small patches.However,subordinates with large patches tended to receive more affiliative acts from their groupmates while performing fewer affiliative acts themselves.Taken together,our results suggest that patch size reflects interindividual variation in foraging effort in this cichlid fish and offer some of the first evidence that colorful signals may shape affiliative relationships withinwildsocialgroups. 展开更多
关键词 affiliation FORAGING Lake Tanganyika Neolamprologus pulcher visual signals
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Assessing display variability in wild brown anoles Anolis sagrei using a mechanical lizard model 被引量:1
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作者 Sarah R. PARTAN Peter OTOVIC +1 位作者 Virginia L. PRICE Scott E. BROWN 《Current Zoology》 SCIE CAS CSCD 北大核心 2011年第2期140-152,共13页
Signals used for species identity ought to be highly stereotyped so as to facilitate immediate recognition by conspecifics. It is surprising therefore to find variability in putative species signature displays. The br... Signals used for species identity ought to be highly stereotyped so as to facilitate immediate recognition by conspecifics. It is surprising therefore to find variability in putative species signature displays. The brown anole Anolis sagrei has a high degree of variability in its signature bobbing display. In this study we collected descriptive data on variability in the temporal structure of wild brown anole bobbing patterns, finding that no two displays analyzed had the same temporal structure, and we also tested whether wild brown anoles prefer the signature display over an alternate display pattern by using mechanical robot playbacks in the field. As a response metric we assessed whether or not the lizards showed social responses (pushup, dewlap extension, or head-nod) in response to the robotic presentations. We found that the lizards responded slightly more to the signature than to the alternate pattern, providing support for the idea that despite the variability seen in displays, the signature pattern is meaningful to them. We tested two other independent variables: speed of the display and elevation of the robot during its display, neither of which was significant. Dewlap extensions were given predominantly by adult males and were more likely to be given in the breeding season than the nonbreeding season. Pushups and head-nods were given equally by males and a combined class of females and juveniles, and were not seasonal. Head-nods increased after the robot turned off, suggesting that they may be used in a conversational turn-taking style during communication . 展开更多
关键词 Species recognition Ethorobotics Visual signals TERRITORIALITY Signature display Sex differences
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A different view: sensory drive in the polarized-light realm 被引量:1
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作者 Thomas W. CRONIN 《Current Zoology》 SCIE CAS CSCD 2018年第4期513-523,共11页
Sensory drive, the concept that sensory systems primarily evolve under the influence of environmen tal features and that animal signals are evolutionarily shaped and tuned by these previously existing sensory systems,... Sensory drive, the concept that sensory systems primarily evolve under the influence of environmen tal features and that animal signals are evolutionarily shaped and tuned by these previously existing sensory systems, has been thoroughly studied regarding visual signals across many animals. Much of this work has focused on spectral aspects of vision and signals. Here, I review work on polarized light signals of animals and relate these to what is known of polarization visual systems, polarized light aspects of visual scenes, and polarizationrelated behavior (e.g., orientation, habitatfinding, contrast enhancement). Other than the broad patterns of scattered polarized light in the sky, most po larization in both terrestrial and aquatic environments results from either reflection or scattering in the horizontal plane. With overhead illumination, horizontal features such as the surfaces of many leaves or of air: water interfaces reflect horizontal polarization, and water scatters horizontally polar ized light under most conditions. Several animal species have been demonstrated to use horizontally polarized light fields or features in critical aspects of their biology. Significantly, most biological sig nals are also horizontally polarized. Here, I present relevant polarizationrelated behavior and discuss the hypothesis that sensory drive has evolutionarily influenced the structure of polarization signals. The paper also considers the evolutionary origin of circular polarization vision and circularly polar ized signals. It appears that this class of signals did not evolve under the influence of sensory drive. The study of signals based on polarized light is becoming a mature field of research. 展开更多
关键词 animal communication polarized light sensory drive VISION visual signal
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Do predator energy demands or previous exposure influence protection by aposematic coloration of prey?
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作者 Petr VESELY Barbora ERNESTOVA +1 位作者 OIdrich NEDVED Roman FUCHS 《Current Zoology》 SCIE CAS CSCD 2017年第3期259-267,共9页
Growing evidence exists that aposematic and toxic prey may be included in a predator's diet when the predator experiences physiological stress. The tree sparrow Passer montanus is known to have a significant portion ... Growing evidence exists that aposematic and toxic prey may be included in a predator's diet when the predator experiences physiological stress. The tree sparrow Passer montanus is known to have a significant portion of aposematic and toxic ladybirds in its natural diet. Here, we present experi- ments testing the attack and eating rate of the tree sparrow toward the invasive aposematic harle- quin ladybird Harmonia axyridis. We wondered whether the sparrow's ability to prey on native ladybirds predisposes them to also prey on harlequin ladybirds. We compared the attack and eat- ing rates of tree sparrows of particular age and/or experience classes to test for any changes during ontogeny (hand-reared x young wild-caught xadult wild-caught) and with differing perceived lev- els of physiological stress (summer adult ~ winter adult). Winter adult tree sparrows commonly at- tacked and ate the offered ladybirds with no evidence of disgust or metabolic difficulties after in- gestion. Naive and wild immature tree sparrows attacked the ladybirds but hesitated to eat them. Adult tree sparrows caught in the summer avoided attacking the ladybirds. These results suggest that tree sparrows are able to cope with chemicals ingested along with the ladybirds. This pre- adaptation enables them to include ladybirds in their diet; though they commonly do this only in times of shortage in insect availability (winter). Young sparrows showed avoidance toward the chemical protection of the ladybirds. 展开更多
关键词 chemical protection toxic prey predation visual signal warning signal.
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