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Erosion risk assessment:A contribution for conservation priority area identification in the sub-basin of Lake tana,north-western Ethiopia

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International Soil and Water Conservation Research 2022年第1期10卷 46-61页

作者： daniel Asfaw Bekele Getachew Workineh Gella Mulualem Asfaw Ejigu Department of Geography and Environmental Studies Bahir Dar UniversityEthiopia Geospatial Data and technology Center(GDtC) Bair Dar UniversityEthiopia Department of Geography and Environmental Studies Debre Tabor UniversityEthiopia

Soil erosion is a serious environmental problem arising from agricultural intensification and landscape *** land management coupled with intense rainfall has intricated the problem in most parts of the Ethiopian *** loss costs a profound amount of the national ***,quantifying soil loss and prioritizing areas for conservation is imperative for proper planning and resource ***,this study has modeled the mean soil loss and annual sediment yield of the Gumara *** 5 tM,Landsat 7EtM+,and Landsat 8 OLI were used for land use land cover(LULC)change *** these,other datasets related to rainfall,digital soil map,Digital Elevation Model,reference land use,and cover(LULC)ground truth points were used to generate parameters for modeling soil *** watershed was classified into five major land-use classes(water body,cultivated land,grazing land,built-up and forest and plantation)using a maximum likelihood algorithm covering a period of the last 30 years(1988-2019).the mean annual soil loss and sediment yield were quantified using RUSLE,Sediment delivery ratio(SDR),and Sediment Yields models(SY).the analysis result unveils that within the past 30 years,the watershed has undergone significant LULC changes from forest&plantation(46.33%)and grazing land to cultivated land(31.59%)with the rate of-1.42km^(2)yr^(-1) and-2.80km^(2)yr^(-1) *** the same vein,the built-up area has expanded to cultivated and grazing ***,nearly 15%(207 km2)of the watershed suffered from moderate to very severe soil *** average,the watershed losses 24.2t ha^(-1) yr^(-1) of soil and yields 2807.02t ha^(-1) yr^(-1) ***,the watershed losses 385,157t ha^(-1)yr^(-1) soil from the whole study *** the admir-ative districts,Farta(Askuma,Giribi,Mahidere Mariam and Arigo kebeles),Fogera(Gazen Aridafofota and Gura Amba kebeles),East Este(Witimera kebele),and Dera(Gedame Eyesus and Deriana Wechi

关键词： Phrases Erosion Sediment yield Landscape GIS Cumara watershed

What is the sound of fear？ Behavioral responses of white-crowned sparrows Zonotrichia leucophrys to synthesized nonlinear acoustic phenomena

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Current Zoology 2014年第4期60卷 534-541页

作者： Ellen K. BLESDOE daniel t. BLUMStEIN the Rocky Mountain Biological Laboratory Box 519 Crested Butte CO 81224 USA Department of Ecology and Evolutionary Biology University of California 621 Young Drive South Los Angeles CA 90095-1606 USA

Fear and anxiety may be adaptive responses to life-threatening situations, and animals may communicate fear to others vocally. A fundamental understanding of fear inducing sounds is important for both wildlife conservation and management because it helps us understand how to design repellents and also how (and why) animals may be negatively impacted by anthropogenic sounds. Nonlinear phenomena—sounds produced by the desynchronization of vibrations in a sound production system—are commonly found in stress-induced animal vocalizations, such as in alarm calls, mobbing calls, and fear screams. there are several functional hypotheses for these nonlinear phenomena. One specific hypothesis is the unpredictability hypothesis, which suggests that because nonlinear phenomena are more variable and somewhat unpredictable, animals are less likely to habituate to them. Animals should, therefore, have a prolonged response to sounds with nonlinear phenomena than sounds without them. Most of the studies involving nonlinear phenomena have used mammalian subjects and conspecific stimuli. Our study focused on white-crowned sparrows (Zonotrichia ***) and used synthesized acoustic stimuli to investigate behavioral responses to stimuli with and without nonlinear phenomena. We predicted that birds would be less relaxed after hearing a stimulus with a nonlinear component. We calculated the difference from baseline of proportion of time spent in relaxed behaviors and performed pair-wise comparisons between a pure tone control stimulus and each of three experimental stimuli, including a frequency jump up, a frequency jump down, and white noise. these comparisons showed that in the 30‒60 s after the playback experiment, birds were significantly less relaxed after hearing noise or an abrupt frequency jump down an octave but not an abrupt frequency jump up an octave or a pure tone. Nonlinear phenomena, therefore, may be generally arousing to animals and may explain why these a

关键词：非线性现象行为反应反应合成声音恐惧声学现象麻雀野生动物保护

A critical evaluation of subjective ratings： Unacquainted observers can reliably assess certain personality traits

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Current Zoology 2014年第2期60卷 162-169页

作者： Matthew B.PEtELLE daniel t.BLUMStEIN Department of Ecology and Evolutionary Biology University of California Los Angeles CA 90095-1606 USA Rocky Mountain Biological Laboratory Crested Butte CO 81224 USA

Methods to measure consistent individual differences in behavior (i.e. animal personality) fall into two categories, subjective ratings and behavioral codings. Ratings are seldom used despite being potentially more efficient than codings. One potential limitation for the use of ratings is that it is assumed that long-term observers or experts in the field are required to score individuals. this can be problematic in many cases, especially for long-term ecological studies where there is high turnover in personnel. We tested whether raters who were unacquainted with subjects could produce reliable and valid personality assessments of yellow-bellied marmotsMarmota flaviventris. two raters, previously unacquainted with individuals and marmot behavior, scored 130 subjects on fifteen different adjectives in both open-field (OF) and mirror image stimulation (MIS) trials. Eight OF and nine MIS adjectives were reliable as indicated by both a high degree of intra-observer and inter-observer reliability. Additionally, some ratings were externally valid, correlating with behavioral codings. Our data suggest that activity/exploration and sociability can be a reliable and valid measurement of personality traits in studies where raters were unacquainted with subjects. these traits are observable with the personality tests we used; otherwise researchers using unacquainted raters should be cautious in the tests they employ.

关键词：主观评价性格特征观察者评估长期生态研究个性特征个体差异临床试验

Deepfake Video Detection Employing Human Facial Features

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Journal of Computer and Communications 2023年第12期11卷 1-13页

作者： daniel Schilling Weiss Nguyen Desmond t. Ademiluyi Computer Science (DSCS) Aspen University Phoenix USA

Deepfake technology can be used to replace people’s faces in videos or pictures to show them saying or doing things they never said or did. Deepfake media are often used to extort, defame, and manipulate public opinion. However, despite deepfake technology’s risks, current deepfake detection methods lack generalization and are inconsistent when applied to unknown videos, i.e., videos on which they have not been trained. the purpose of this study is to develop a generalizable deepfake detection model by training convoluted neural networks (CNNs) to classify human facial features in videos. the study formulated the research questions: “How effectively does the developed model provide reliable generalizations?” A CNN model was trained to distinguish between real and fake videos using the facial features of human subjects in videos. the model was trained, validated, and tested using the FaceForensiq++ dataset, which contains more than 500,000 frames and subsets of the DFDC dataset, totaling more than 22,000 videos. the study demonstrated high generalizability, as the accuracy of the unknown dataset was only marginally (about 1%) lower than that of the known dataset. the findings of this study indicate that detection systems can be more generalizable, lighter, and faster by focusing on just a small region (the human face) of an entire video.

关键词： Artificial Intelligence Convoluted Neural Networks Deepfake GANs Generalization Deep Learning Facial Features Video Frames

Experimental studies on the erosion rate of different heat treated carbon steel economiser tubes of power boilers by fly ash particles

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International Journal of Minerals,Metallurgy and Materials 2009年第5期16卷 534-539页

作者： t.A.daniel Sagayaraj S.Suresh M.Chandrasekar Department of Mechanical Engineering National Institute of Technology Tiruchirappalli-620015Tamil NaduIndia

the experimental investigations on the effect of the fly ash particle size, velocity, impingement angle, and feed rate were done with an emphasis on the effect of erosion on annealed SA 210 GrA1 （A） and normalized SA 210 GrA1 （N） carbon steel economizer-tube materials. Erosion rates were evaluated with different impingement angles ranging from 15° to 90°, at four different velocities of 32.5, 35, 37.5, and 40 m/s, and at four different feed rates of fly ash particles of 2, 4, 6 and 8 g/min. the erodent used was fly ash particles, sizes ranging from 50-250 μm of irregular shapes. Erosion rate is found to be the maximum at the impingement angle of 30°. Erosion rates of the carbon steel tube in different heat treatment conditions, annealed and normalized, at a constant velocity of 32.5 m/s with different angles were studied. In all cases of feed rates, impingement angles, particle sizes, and velocities of fly ash particles, it has been found that the erosion rate of the annealed tube is less than that of the normalized tube. Empirical correlations for erosion rate relating the velocity, size, feed rate, and impingement angle of the particles and elongation property of the target materials were arrived. Morphologies of the eroded surface were examined by scanning electron microscope （SEM）.

关键词： erosion rate economiser tubes annealing normalizing

take only pictures, leave only...fear？ the effects of photography on the West Indian anole Anolis cristatellus

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Current Zoology 2011年第1期57卷 77-82页

作者： Brian HUANG Katie LUBARSKY tiffany tENG daniel t. BLUMStEIN Department of Ecology & Evolutionary Biology University of California 621 Young Drive South Los Angeles CA 90095-1606 USA

Ecotourism encourages an environmentally friendly exploration of the world's natural habitats. tourists often engage in wildlife photography, an activity that is generally not considered disturbing to animals. We investigated the effects of camera-related stimuli to determine whether shutter noise and/or flash affected the immediate behavior of female crested anolesAnolis cristaellus. Anoles decreased their display rate following stimuli that included shutter noises, but did not change their behavior in response to flash or silence treatments. to determine the relative importance of this response, we observed anole behavior following playbacks of calls from kestrelsFalco sparverius, a predator, and bananaquitsCoereba flaveola, a non-predator. Anoles decreased display rates following kestrel calls when compared to their response to bananaquit calls. Furthermore, anoles spent a greater proportion of time displaying following bananaquit calls compared to both kestrel calls and silence. the magnitude of response to shutter noises was about the same as that to predator calls. this demonstrates that photography may not be as benign as commonly believed, and we should consider whether restrictions on camera noises should be implemented to reduce animal disturbance.

关键词：野生动物摄影西印度图片恐惧时间显示自然栖息地生态旅游快门

Response of endemic afroalpine rodents to the removal of livestock grazing pressure

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Current Zoology 2011年第6期57卷 741-750页

作者： Flavie VIAL David W. MACDONALD daniel t. HAYDON Boyd Orr Centre for Population and Ecosystem Health Institute of Biodiversity Animal Health and Comparative Medicine College of Medical Veterinary and Life Sciences University of Glasgow Glasgow G12 8QQ UK. Wildlife Conservation Research Unit Zoology Department University of Oxford The Recanati-Kaplan Centre Tubney House Tubney OX13 5QL UK.

the Bale Mountains of Ethiopia represent the world’s largest continuous extent of afroalpine habitat. With a peak combined density of over 8000 individuals/km2, the endemic giant mole rattachyoryctes macrocephalus, Blick’s grass ratArvicanthis blickiand the brush-furred mouseLophuromys melanonyxare the dominant wild herbivores within this ecosystem and may be affected by the presence of high densities of domestic livestock. the purpose of this study was to establish whether these endemic rodent populations could respond to the removal of grazing pressure inside three 0.25 hectare livestock exclosures (paired with grazed control plots) and to determine whether such response was mediated through concomitant changes in the vegetation structure. We hypothesised that livestock grazing negatively affects endemic rodent populations through competition or increased predation risk and we predicted an increase in rodent biomass following the removal of grazing pressure. We found no evidence of rodent populations responding to the removal of livestock after fourteen months. the short-term nature of the experimental design, environmental fluctuations and the ecosystem’s inherent stochasticity may explain the apparent lack of a significant response. However, while this study is inconclusive, it emphasises the need for more long-term experimental investigations to assess the effects of domestic grazers on vegetation and on dependent communities. the effects of rapidly increasing livestock numbers in the Bale Mountains will require continued close monitoring of vegetation and endemic animal communities as the afroalpine is altered by external biotic and abiotic forces.

关键词：放牧压力地方性啮齿动物反应动物种群牲畜数量食草动物生态系统

Hybrid magnetorheological elastomers enable versatile soft actuators

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npj Computational Materials 2022年第1期8卷 1546-1559页

作者： Miguel Angel Moreno-Mateos Mokarram Hossain Paul Steinmann daniel Garcia-Gonzalez Department of Continuum Mechanics and Structural Analysis Universidad Carlos III de MadridAvda.de la Universidad 3028911LeganésMadridSpain Zienkiewicz Centre for Computational Engineering Faculty of Science and EngineeringSwansea UniversitySA18ENSwanseaUK Institute of Applied Mechanics University of Erlangen-NurembergEgerland Str.5ErlangenGermany Glasgow Computational Engineering Centre School of EngineeringUniversity of GlasgowG128QQGlasgowUK

Recent advances in magnetorheological elastomers(MREs)have posed the question on whether the combination of both soft-and hard-magnetic particles may open new routes to design versatile multifunctional ***,we conceptualise ultra-soft hybrid MREs(≈1–10 kPa stiffness)combining experimental and computational ***,a comprehensive experimental characterisation is *** results unravel that the magneto-mechanical performance of hybrid MREs can be optimised by selecting an adequate mixing ratio between ***,a multi-physics computational framework provides insights into the synergistic magneto-mechanical interactions at the *** particles amplify the magnetisation and hard particles contribute to torsional *** numerical results suggest that the effective response of hybrid MREs emerges from these intricate ***,we uncover exciting possibilities to push the frontiers of MRE *** are demonstrated by simulating a bimorph beam that provides actuation flexibility either enhancing mechanical bending or material stiffening,depending on the magnetic stimulation.

关键词： versatile magneto enable

Introduction to the special column： communication, cooperation, and cognition in predators

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Current Zoology 2017年第3期63卷 295-299页

作者： Arik KERSHENBAUM daniel t. BLUMStEN Department of Zoology University of Cambridge Cambridge CB23EJ UK Evolutionary Biology University of California Los Angeles CA 90095-1606 USADepartment of Ecology and

Communication is the glue that holds societies together and we might expect that highly social species with more to communicate about will have more complex communication systems and more complex cognitive abilities. Social species gain benefits from living in groups, and many of these benefits rely on intra-group communication. For example, predator-specific alarm calls can lead to different evasion responses (Suzuki 2014), or difficult to obtain food resources can be acquired using aggregation calls (King and Janik 2015).

关键词：捕食者交流合作社会性认知能力通讯系统群体生活回避反应