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1.
Five laboratory-raised Japanese monkeys (Macaca fuscata) were presented various types of photographs of Japanese and rhesus monkeys (Macaca mulatta) in upright, horizontal, and inverted orientations in a sensory-reinforcement experiment. The ratio of the duration of potential viewing time for the photographs which the subjects controlled to the interval between subject-controlled presentations of them (the D/I score) was used as a measure of preference for the photographs. When inverted photographs were presented, the D/I scores were lower than for upright photographs. The difference in D/I scores between photographs of the two species, which indicated discriminability between them, also diminished when the photographs were inverted. The results obtained suggest an inversion effect in face perception in macaque monkeys.  相似文献   

2.
The aim of the study was to determine the acceptance and perception of Nigerian patients to medical photography. A self‐administered questionnaire was distributed among Nigerian patients attending oral and maxillofacial surgery and plastic surgery clinics of 3 tertiary health institutions. Information requested included patients' opinion about consent process, capturing equipment, distribution and accessibility of medical photographs. The use of non‐identifiable medical photographs was more acceptable than identifiable to respondents for all purposes (P = 0.003). Most respondents were favourably disposed to photographs being taken for inclusion in the case note, but opposed to identifiable photographs being used for other purposes most especially in medical websites and medical journals. Female respondents preferred non‐identifiable medical photographs to identifiable ones (P = 0.001). Most respondents (78%) indicated that their consent be sought for each of the outline needs for medical photography. Half of the respondents indicated that identifiable photographs may have a negative effect on their persons; and the most commonly mentioned effects were social stigmatization, bad publicity and emotional/psychological effects. Most of the respondents preferred the use of hospital‐owned camera to personal camera/personal camera‐phone for their medical photographs. Most respondents (67.8%) indicated that they would like to be informed about the use of their photographs on every occasion, and 74% indicated that they would like to be informed of the specific journal in which their medical photographs are to be published. In conclusion, non‐identifiable rather than identifiable medical photography is acceptable to most patients in the studied Nigerian environment. The use of personal camera/personal camera‐phone should be discouraged as its acceptance by respondents is very low. Judicious use of medical photography is therefore advocated to avoid breach of principle of privacy and confidentiality in medical practice.  相似文献   

3.
The display of personal photographs in hospital is a common practice that has yet to be rigorously examined. The photographs displayed are subject to interpretation by the viewer and may lead to misunderstandings or miscommunication if clarification of meaning is not sought. This paper explores a range of possible meanings that the display of photographs in hospital may hold, based on a case study of a 15 year old boy hospitalised with a life threatening illness. Further research is needed into the actual meanings attributed to the display of photographs in hospital by patients and family members.  相似文献   

4.
Photographs, especially of humans, are widely used as stimuli in behavioural research with pigeons. Despite their abundant use, it is not clear to what extent pigeons perceive photographs as representing three-dimensional objects. To address this question, we trained 16 pigeons to identify individual, real-life humans. This discrimination depended primarily on visual cues from the heads of the persons. Subsequently, the pigeons were shown photographs of these individuals to test for transfer to a two-dimensional representation. Successful identification of a three-dimensional person did not facilitate learning of the corresponding photographs. These results demonstrate limitations of cross-recognition of complex objects and their photographs in pigeons.  相似文献   

5.
Hemispherical photography is a well-established method to optically assess ecological parameters related to plant canopies; e.g. ground-level light regimes and the distribution of foliage within the crown space. Interpreting hemispherical photographs involves classifying pixels as either sky or vegetation. A wide range of automatic thresholding or binarization algorithms exists to classify the photographs. The variety in methodology hampers ability to compare results across studies. To identify an optimal threshold selection method, this study assessed the accuracy of seven binarization methods implemented in software currently available for the processing of hemispherical photographs. Therefore, binarizations obtained by the algorithms were compared to reference data generated through a manual binarization of a stratified random selection of pixels. This approach was adopted from the accuracy assessment of map classifications known from remote sensing studies. Percentage correct () and kappa-statistics () were calculated. The accuracy of the algorithms was assessed for photographs taken with automatic exposure settings (auto-exposure) and photographs taken with settings which avoid overexposure (histogram-exposure). In addition, gap fraction values derived from hemispherical photographs were compared with estimates derived from the manually classified reference pixels. All tested algorithms were shown to be sensitive to overexposure. Three of the algorithms showed an accuracy which was high enough to be recommended for the processing of histogram-exposed hemispherical photographs: “Minimum” ( 98.8%; 0.952), “Edge Detection” ( 98.1%; 0.950), and “Minimum Histogram” ( 98.1%; 0.947). The Minimum algorithm overestimated gap fraction least of all (11%). The overestimation by the algorithms Edge Detection (63%) and Minimum Histogram (67%) were considerably larger. For the remaining four evaluated algorithms (IsoData, Maximum Entropy, MinError, and Otsu) an incompatibility with photographs containing overexposed pixels was detected. When applied to histogram-exposed photographs, these algorithms overestimated the gap fraction by at least 180%.  相似文献   

6.
The effects of perceived cuteness of infant photographs on the behaviour of young adults was investigated. Looking, facial muscle activity, and skin conductance were measured during individual presentations of the photographs, whereas only looking was measured during paired presentations. Both measures of looking time were significantly affected by the perceived cuteness of infant photographs, with infants ranked as most cute looked at longest and those ranked least cute looked at for the shortest length of time. Increased facial muscle activity previously associated with pleasant or happy facial expressions was associated with presentations of infant photographs but was not related to perceived cuteness. A second experiment indicated that increased facial muscle activity was specific to infant photographs. Adult responses to infant physical appearance appear to be regulated by two mechanisms: an initial positive response to “babyishness”, reflected by increased facial zygomaticus muscle activity, and an individual cognitive preference response to “cuteness”, reflected by differential looking times.  相似文献   

7.
  1. Color research continuously demands better methods and larger sample sizes. Citizen science (CS) projects are producing an ever‐growing geo‐ and time‐referenced set of photographs of organisms. These datasets have the potential to make a huge contribution to color research, but the reliability of these data need to be tested before widespread implementation.
  2. We compared the difference between color extracted from CS photographs with that of color extracted from controlled lighting conditions (i.e., the current gold standard in spectrometry) for both birds and plants. First, we tested the ability of CS photographs to quantify interspecific variability by assessing > 9,000 CS photographs of 537 Australian bird species with controlled museum spectrometry data. Second, we tested the ability of CS photographs to quantify intraspecific variability by measuring petal color data for two plant species using seven methods/sources with varying levels of control.
  3. For interspecific questions, we found that by averaging out variability through a large sample size, CS photographs capture a large proportion of across species variation in plumage color within the visual part of the spectrum (R2 = 0.68–0.71 for RGB space and 0.72–0.77 for CIE‐LAB space). Between 12 and 14 photographs per species are necessary to achieve this averaging effect for interspecific studies. Unsurprisingly, the CS photographs taken with commercial cameras failed to capture information in the UV part of the spectrum. For intraspecific questions, decreasing levels of control increase the color variation but averaging larger sample sizes can partially mitigate this, aside from particular issues related to saturation and irregularities in light capture.
  4. CS photographs offer a very large sample size across space and time which offers statistical power for many color research questions. This study shows that CS photographs contain data that lines up closely with controlled measurements within the visual spectrum if the sample size is large enough, highlighting the potential of CS photographs for both interspecific and intraspecific ecological or biological questions. With regard to analyzing color in CS photographs, we suggest, as a starting point, to measure multiple random points within the ROI of each photograph for both patterned and unpatterned patches and approach the recommended sample size of 12–14 photographs per species for interspecific studies. Overall, this study provides groundwork in analyzing the reliability of a novel method, which can propel the field of studying color forward.
  相似文献   

8.
This article describes and tests a photography rig that has been built at the University of Melbourne, Australia, specifically for the purpose of taking rapid and highly standardized craniofacial photographs, in simultaneous views of front and profile. The rig uses a novel projected light range-finding system that has been designed for easy and accurate positioning of subjects, in the natural head position, at precise distances from the frontal camera. Results of experiments examining the intraobserver error of multiple photographs taken on the rig indicate that high-quality, repeatable photographs can be taken after a reasonably large amount of time has lapsed between photography sessions (e.g., 30 days). This study also indicates that some variability remains between photographs even when highly standardized protocols are followed. Consequently, it is expected that the variation between photographs with limited standardization is much larger and more likely to cause significant errors in any comparisons.  相似文献   

9.
Four groups of pigeons were trained on four visual discrimination tasks using people photographs, pigeon photographs, cartoons of people, and cartoons of pigeons. After completion of the discrimination, the subjects were tested with new stimuli in the same stimulus categories but never used during the training, and scrambled stimuli in which elements of the original stimulus were spatially randomized. The subjects showed generalization to the new stimuli except for the people cartoons. When scrambled stimuli were presented, the subjects showed suppression of responding to the photographs but not to the people cartoon. These results suggest that the pigeons recognized both the elements and spatial arrangement of the photographs but ignored the spatial arrangement of the human cartoons.  相似文献   

10.
Abstract. Historical aerial photographs are an important source for data on medium- to long-term (10 - 50 yr) vegetation changes. Older photographs are panchromatic, and manual interpretation has traditionally been used to derive vegetation data from such photographs. We present a method for computerized analysis of panchromatic aerial photographs, which enables one to create high resolution, accurate vegetation maps. Our approach is exemplified using two aerial photographs (from 1964 and 1992) of a test area on Mt. Meron, Israel. Spatial resolution (pixel size) of the geo-rectified photos was 0.30 m and spatial accuracy (RMS error) ca. 1 m. An illumination adjustment prior to classification was found to be essential in reducing misclassification error rates. Two classification approaches were employed: a standard maximum-likelihood supervised classifier, and a modification of a supervised classification, which takes into account spectral properties of individual pixels as well as their neighbourhood characteristics. Accuracy of the maximum likelihood classification was 81 % in the 1992 image and 54 % in the 1964 image. The neighbour classifier increased accuracy to 89 % and 82 % respectively. The overall results suggest that computerized analysis of sequences of panchromatic aerial photographs may serve as a valuable tool for the quantification of medium-term vegetation changes.  相似文献   

11.
Non-destructive estimation using digital cameras is a common approach for estimating leaf area index (LAI) of terrestrial vegetation. However, no attempt has been made so far to develop non-destructive approaches to LAI estimation for aquatic vegetation. Using the submerged plant species Potamogeton malainus, the objective of this study was to determine whether the gap fraction derived from vertical photographs could be used to estimate LAI of aquatic vegetation. Our results suggested that upward-oriented photographs taken from beneath the water surface were more suitable for distinguishing vegetation from other objects than were downward-oriented photographs taken from above the water surface. Exposure settings had a substantial influence on the identification of vegetation in upward-oriented photographs. Automatic exposure performed nearly as well as the optimal trial exposure, making it a good choice for operational convenience. Similar to terrestrial vegetation, our results suggested that photographs taken for the purpose of distinguishing gap fraction in aquatic vegetation should be taken under diffuse light conditions. Significant logarithmic relationships were observed between the vertical gap fraction derived from upward-oriented photographs and plant area index (PAI) and LAI derived from destructive harvesting. The model we developed to depict the relationship between PAI and gap fraction was similar to the modified theoretical Poisson model, with coefficients of 1.82 and 1.90 for our model and the theoretical model, respectively. This suggests that vertical upward-oriented photographs taken from below the water surface are a feasible alternative to destructive harvesting for estimating PAI and LAI for the submerged aquatic plant Potamogeton malainus.  相似文献   

12.
With a free-choice task, visual preference was estimated in five adult chimpanzees (Pan troglodytes). The subjects were presented with digitized color photographs of various species of primates on a CRT screen. Their touching responses to the photographs were reinforced by food reward irrespective of which photographs they touched. The results revealed that all chimpanzees touched the photographs of humans significantly more than any other species, or phylogenetic families of primates. This tendency was consistent across different stimulus sets. The results suggest that the chimpanzees showed visual preference for the photographs of humans over those of their own species. The results also suggest that the degree of this visual preference was not in accordance with phylogenetic distance from the subjects' species, chimpanzees. The preference for humans was stronger in the case of the colored photographs than in monochromatic ones. All of the five chimpanzees had been in captivity for at least 16 years. They were reared by humans from just after their birth, or at least from 1.5 years old. Their preference might have developed through social experience, especially that during infanthood. Electronic Publication  相似文献   

13.
Achieving standardized photographs in aesthetic surgery   总被引:2,自引:0,他引:2  
The plastic surgeon who wishes to share clinical experience with colleagues is obligated to produce accurate data in the form of photographs. Moreover, accurate photographs are essential to enable an objective critical appraisal of one's own surgical skill and to display postoperative results to patients in an unbiased fashion. Change should not be a function of either the photograph or the photographer. The use of an acetate screen grid in conjunction with anatomic boundaries is described as a means to achieve accurate, reproducible standard photographs of the face and body in aesthetic surgical patients.  相似文献   

14.
Repeat photography is an efficient method for documenting long-term landscape changes. So far, the usage of repeat photographs for quantitative analyses is limited to approaches based on manual classification. In this paper, we demonstrate the application of a convolutional neural network (CNN) for the automatic detection and classification of woody regrowth vegetation in repeat landscape photographs. We also tested if the classification results based on the automatic approach can be used for quantifying changes in woody vegetation cover between image pairs. The CNN was trained with 50 × 50 pixel tiles of woody vegetation and non-woody vegetation. We then tested the classifier on 17 pairs of repeat photographs to assess the model performance on unseen data. Results show that the CNN performed well in differentiating woody vegetation from non-woody vegetation (accuracy = 87.7%), but accuracy varied strongly between individual images. The very similar appearance of woody vegetation and herbaceous species in photographs made this a much more challenging task compared to the classification of vegetation as a single class (accuracy = 95.2%). In this regard, image quality was identified as one important factor influencing classification accuracy. Although the automatic classification provided good individual results on most of the 34 test photographs, change statistics based on the automatic approach deviated from actual changes. Nevertheless, the automatic approach was capable of identifying clear trends in increasing or decreasing woody vegetation in repeat photographs. Generally, the use of repeat photography in landscape monitoring represents a significant added value to other quantitative data retrieved from remote sensing and field measurements. Moreover, these photographs are able to raise awareness on landscape change among policy makers and public as well as they provide clear feedback on the effects of land management.  相似文献   

15.
Book Reviews     
Book reviewed in this article:
Primula . John Richards. 299 pp., 116 colour paintings (19 plates), 51 colour and 10 black-and-white photographs, 17 line drawings.
Kew, A World of Plants . Heather Angel. 160 pp., 146 colour photographs, 1 map. Collins & Brown, London, in association with the Royal Botanic Gardens, Kew. 1993.
Pests and Diseases of Alpine Plants . P.R. Ellis, A.R. Entwistle & D.G.A. Walkey. 320 pp., 28 colour plates (163 photographs), 35 black-and-white figures including 2 plates (12 photographs), 50 tables.  相似文献   

16.
Book Reviews     
Book reviewed in this article:
Orchid Photography. Charles Marden Fitch. 96 pp., over 150 colour photographs. American Orchid Society, 6000 South Olive Avenue, West Palm Beach, Florida 33405.
Collins Photo Guide to Orchids of Britain and Europe. Pierre Delforge. 480 pp., 812 colour photographs.
Flowers of Sri Lanka. S.R. Kottegoda. 247 pp., 411 colour photographs. Royal Asiatic Society of Sri Lanka, Colombo 07. 1994.  相似文献   

17.
Book Reviews     
Book reviewed in this article:
The Cattleyas and their Relatives. Vol. III. Schomburgkia, Sophronitis, and other South American Genera. Carl L. Withner. 136 pp., 85 colour photographs, numerous b/w line drawings.
'Chinese Wilson'. A Life of Ernest H. Wilson 1876–1930. Roy W. Briggs with a foreword by Roy Lancaster.
Gardens of Historic Charleston. James R. Cothran. 177 pp., numerous colour and b/w photographs, illustrations and portraits.
Science in the Pleasure Ground. A History of the Arnold Arboretum. Ida Hay. 349 pp., 20 colour photographs, numerous black and white photographs, maps and plans.  相似文献   

18.
Ethnobotanists use a variety of interview techniques to collect ethnobotanical data. Drawing upon the results from a quantitative ethnobotanical study in five Yuracaré and Trinitario communities in the Bolivian Amazon, the pros and cons of the following methods are evaluated: (1) interviews in situ during transects, walk-in-the-woods, and homegarden sampling; and (2) interviews ex situ with fresh plant material, voucher specimens, or plant photographs as reference tools. Although the systematic use of plant photographs for ethnobotanical interviews is poorly documented in literature, the results show that indigenoùs participants in our study recognize significantly more plant species from photographs than from voucher specimens. It is argued that, especially in remote and isolated study sites, photographs might be advantageous over voucher specimens.  相似文献   

19.
云南江城县地处西双版纳生物多样性保护的优先区域,历史上未展开过全面系统的爬行动物资源调查。本研究于2019年5月至2020年9月期间,先后7次(5 ~ 10 d/月,8:00时至次日04:00时),调查江城县全域爬行动物多样性。调查采用固定样线法,共设置207条样线,每条长4 km,本次调查共记录爬行动物2目17科39属51种,其中国家一级重点保护野生动物物种1种,圆鼻巨蜥(Varanus salvator),国家二级重点保护野生动物物种7种。本次调查发现2新种和1种中国分布新记录及1种云南分布新记录,新种为伯仲钝头蛇(Pareas geminates sp. nov)和滇南竹叶青蛇(Trimeresurus goui sp. nov),中国新记录种为老挝拟须唇蛇(Parafimbrios lao),云南新记录种为崇安斜鳞蛇(Pseudoxenodon karlschmidti)。通过分析发现,江城县爬行动物物种多样性丰富,该区分布的物种区系以东洋界为主,单属种较多,与喜马拉雅-横断山具有一定的联系。其6类生态型中,灌丛石隙型最丰富。垂直分布多样性最丰富的是山坡地带海拔700 ~ 1 500 m。江城的地理位置以及气候与植被环境,是研究季雨林爬行动物多样性组成的典型区域,本次调查研究弥补了该地区爬行动物多样性文献资料的空白,建议未来维持现有的森林分布格局,加强对该地区爬行动物多样性的研究、监测和保护。  相似文献   

20.
人类干扰影响着野生动物的栖息、生存、繁衍等各个环节。干扰强度不同,对野生动物的负面影响也不同。为了了解不同强度人类干扰对野生动物栖息的影响,2021年1月,在浙江百山祖国家级自然保护区,根据人为干扰综合强度预先设定点位,布设40台红外相机。40个点位被分为4种干扰区,干扰强度从低到高依次为基本无干扰区、干扰轻微区、干扰较轻区和干扰较重区,每区10个点位,监测365 d,共监测14 585相机日。研究表明:(1)拍摄到野生动物独立照片4 256张,其中兽类3 485张,鸟类771张。除啮齿类动物外,拍摄到31种动物,其中兽类14种、鸟类17种,另外有3张因照片不够清晰而未能识别鸟的种类。国家一级重点保护野生动物2种,国家二级重点保护野生动物9种。(2)基本无干扰区、干扰轻微区、干扰较轻区及干扰较重区所拍摄到的野生动物独立照片数量和种类分别为1 798张29种(兽类15种,鸟类14种)、1 308张23种(兽类15种,鸟类8种)、756张19种(兽类12种,鸟类7种)、394张18种(兽类13种,鸟类5种),各区之间的独立照片数量差异极显著(P < 0.01)。随着人类干扰强度的增加,拍摄到的独立照片数量逐渐减少,拍摄到的独立照片数量与人类干扰强度之间存在极显著的负线性关系(P < 0.01)。同时,随着人类干扰强度的增加,拍摄到的野生动物种类也逐渐减少,尤其是鸟类减少幅度更大。(3)国有林内23台相机拍摄到3 163张,计33种(兽类16种、鸟类17种);集体林内17台相机拍摄到1 093张,计22种(其中兽类13种、鸟类9种)。集体林内平均每台红外相机拍摄到的照片数量为国有林的46.75%,差异极显著(P < 0.01),这可能是由于早些年份的林木采伐使栖息地遭受不同程度的破坏,并导致生境片段化,进而影响野生动物栖息。因而,对于野生动物保护来说,栖息地保护是一项相当重要的工作。  相似文献   

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