scholarly journals Comparing radio-tracking and visual detection methods to quantify group size measures

2015 ◽  
Vol 1 (2) ◽  
pp. 1-4 ◽  
Author(s):  
Jenő Reiczigel ◽  
María Fernanda Mejía Salazar ◽  
Trent K. Bollinger ◽  
Lajos Rózsa
Keyword(s):  
Group Size ◽  
Rocky Mountain ◽  
Field Studies ◽  
Visual Observation ◽  
Detection Methods ◽  
Data Sets ◽  
Animal Group ◽  
Two Samples ◽  
In The Wild ◽  
Group Size Distribution

Abstract1. Average values of animal group sizes are prone to be overestimated in traditional field studies because small groups and singletons are easier to overlook than large ones. This kind of bias also applies for the method of locating groups by tracking previously radio-collared individuals in the wild. If the researcher randomly chooses a collared animal to locate a group to visit, a large group has higher probability to be selected than a small one, simply because it has more members.2. The question arises whether location of groups by means of finding collared animals has smaller or greater bias than searching for groups by visual observation. If the bias is smaller or same, this method can be recommended for finding groups. However, such a comparison cannot be made by speculation, only by empirical investigation.3. The present study compares the two methods empirically, by statistically comparing group size measures (mean, median, quantiles, frequency distribution, and ‘typical group size’) between two data sets. These data sets comprise of Rocky Mountain mule deer group size values collected in the same area during the same period of time, referring either to groups located by the traditional ‘search and observe method’ or located by tracking formerly collared individuals.4. All group size measures are statistically similar in the two samples, thus we conclude that the two methods yielded similar biases. Although the true group size measures are not known, we presume that both methods have overestimated them. We propose that these results do not necessary apply to other species, thus cannot be generalized. The reason for this is that bias may depend on factors specific to the species: bias of visual observation may depend on how well the species conceals itself in the existing habitat, and the bias associated with finding groups using collared animals is likely dependent on group size distribution and also on the proportion of collared animals in the population.

scholarly journals Comparison of Novelty Detection Methods for Detection of Various Rotary Machinery Faults

Sensors ◽  
2021 ◽  
Vol 21 (10) ◽  
pp. 3536
Author(s):  
Jakub Górski ◽  
Adam Jabłoński ◽  
Mateusz Heesch ◽  
Michał Dziendzikowski ◽  
Ziemowit Dworakowski
Keyword(s):  
Novelty Detection ◽  
Feature Space ◽  
Detection Methods ◽  
Data Sets ◽  
Similar Distribution ◽  
Detection Algorithms ◽  
Rotary Machinery ◽  
Detection Approach ◽  
Input Reconstruction ◽  
Quantitative Indicators

Condition monitoring is an indispensable element related to the operation of rotating machinery. In this article, the monitoring system for the parallel gearbox was proposed. The novelty detection approach is used to develop the condition assessment support system, which requires data collection for a healthy structure. The measured signals were processed to extract quantitative indicators sensitive to the type of damage occurring in this type of structure. The indicator’s values were used for the development of four different novelty detection algorithms. Presented novelty detection models operate on three principles: feature space distance, probability distribution, and input reconstruction. One of the distance-based models is adaptive, adjusting to new data flowing in the form of a stream. The authors test the developed algorithms on experimental and simulation data with a similar distribution, using the training set consisting mainly of samples generated by the simulator. Presented in the article results demonstrate the effectiveness of the trained models on both data sets.

scholarly journals Group size and aquatic vegetation modulates male preferences for female shoals in wild zebrafish, Danio rerio

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Aditya Ghoshal ◽  
Anuradha Bhat
Keyword(s):  
Group Size ◽  
Aquatic Vegetation ◽  
Natural Habitat ◽  
Ecological Factors ◽  
Choice Test ◽  
Female Group ◽  
Aquatic Flora ◽  
In The Wild ◽  
The Individual

AbstractShoaling decisions in the wild are determined by a combination of innate preferences of the individual along with the interplay of multiple ecological factors. In their natural habitat as well as in the laboratory, zebrafish is a shoaling fish. Here, we investigate the role of group size and associated vegetation in shaping shoaling preferences of wild male zebrafish. We studied the association preference of males to groups of female shoals in a multi-choice test design. We found that males made greater proportion of visits to an 8-female group compared to 2 and 4-female groups. However, males spent similar proportions of time across the three female-containing groups. When artificial vegetation was incorporated along with female number as an additional factor, we found that males prefer high and moderately vegetated patches compared to low or no-vegetation groups, irrespective of the number of females in these patches. Based on experiments using a novel multi-choice design, our results show that preference for group size can change due to interaction of two separate factors. This work is a first attempt to understand the role of aquatic flora in determining shoaling preferences in zebrafish, using an experimental paradigm consisting of a gradation in female and vegetation densities.

Enzootic Activity of Chlamydia in Farms Located in a Hotspot Area for Zoonosis Emergence

2021 ◽  
Author(s):  
Ezequiel Andres Vanderhoeven ◽  
Jessica P. Mosmann ◽  
Adrián Díaz ◽  
Cecilia G. Cuffini
Keyword(s):  
Bird Species ◽  
Farm Animals ◽  
Economic Losses ◽  
Wild Mammals ◽  
Specific Pcr ◽  
Chlamydial Species ◽  
Zoonotic Risk ◽  
Two Samples ◽  
In The Wild ◽  
First Time

Abstract Chlamydias are obligated intracellular Gram-negative bacteria, considered important zoonotic pathogens, broadly present in several bird species and responsible for economic losses in animal production. We analyzed the presence of Chlamydial species with zoonotic risk in farm animals in a highly biodiverse area and with great human circulation, the Argentine, Brazil and Paraguay tri-border area. We surveyed nine farms in an area and nasally swabbed a total of 62 animals. DNA was extracted and specific PCR was performed to identify chlamydial species. We detected Chlamydia spp . in 6.5% (4/62) of the animals tested, positive samples belonged to cattle and none of them showed symptoms of respiratory disease nor had been diagnose with reproductive diseases. Specific nested PCR confirmed two samples belonged to C. pecorum and two to C. psittaci . We report for the first time Chlamydia circulation with zoonotic risk in the region. Surveys in birds and wild mammals could give a better understanding to know what Chlamydial species are circulating in the wild interface. The zoonotic potential should be taking into account as farm workers and the surrounding population could be silent carriers or have respiratory diseases being underdiagnosed, and therefore should be considered in the differential diagnoses.

scholarly journals Instantaneous areal population density of entire Atlantic cod and herring spawning groups and group size distribution relative to total spawning population

2018 ◽  
Vol 20 (2) ◽  
pp. 201-213 ◽  
Author(s):  
Nicholas C. Makris ◽  
Olav Rune Godø ◽  
Dong Hoon Yi ◽  
Gavin J. Macaulay ◽  
Ankita D. Jain ◽  
...  
Keyword(s):  
Population Density ◽  
Size Distribution ◽  
Group Size ◽  
Atlantic Cod ◽  
Group Size Distribution

scholarly journals Uncertainty-Aware Deep Classifiers Using Generative Models

2020 ◽  
Vol 34 (04) ◽  
pp. 5620-5627 ◽  
Author(s):  
Murat Sensoy ◽  
Lance Kaplan ◽  
Federico Cerutti ◽  
Maryam Saleki
Keyword(s):  
Neural Networks ◽  
Epistemic Uncertainty ◽  
Feature Space ◽  
Generative Models ◽  
Detection Methods ◽  
Generative Adversarial Networks ◽  
Data Sets ◽  
Bayesian Approaches ◽  
Data Set ◽  
Auxiliary Data

Deep neural networks are often ignorant about what they do not know and overconfident when they make uninformed predictions. Some recent approaches quantify classification uncertainty directly by training the model to output high uncertainty for the data samples close to class boundaries or from the outside of the training distribution. These approaches use an auxiliary data set during training to represent out-of-distribution samples. However, selection or creation of such an auxiliary data set is non-trivial, especially for high dimensional data such as images. In this work we develop a novel neural network model that is able to express both aleatoric and epistemic uncertainty to distinguish decision boundary and out-of-distribution regions of the feature space. To this end, variational autoencoders and generative adversarial networks are incorporated to automatically generate out-of-distribution exemplars for training. Through extensive analysis, we demonstrate that the proposed approach provides better estimates of uncertainty for in- and out-of-distribution samples, and adversarial examples on well-known data sets against state-of-the-art approaches including recent Bayesian approaches for neural networks and anomaly detection methods.

Into the wild: developing field tests to examine the link between elasmobranch personality and laterality

Behaviour ◽  
2016 ◽  
Vol 153 (13-14) ◽  
pp. 1777-1793 ◽  
Author(s):  
Evan E. Byrnes ◽  
Catarina Vila Pouca ◽  
Sherrie L. Chambers ◽  
Culum Brown
Keyword(s):  
Personality Traits ◽  
Field Tests ◽  
Animal Personality ◽  
Field Studies ◽  
Individual Level ◽  
In The Wild ◽  
Port Jackson ◽  
The Relationship

The field of animal personality has received considerable attention in past decades, yet few studies have examined personality in the wild. This study investigated docility, a measure of boldness, in two Port Jackson shark (Heterodontus portusjacksoni) populations using field tests, and if laterality differences explained docility levels. We developed a struggle test as an assay for docility, which is particularly amenable to field studies. The struggle test was effective, and repeatable inter-individual docility differences were observed. Sex, but not population, influenced docility scores, with male sharks being less docile than females. This difference is likely due to the contrasting role each sex plays during mating. We also found individualized lateralization. However, no individual-level relationship between lateralization and docility was detected. Despite reported links between laterality and some personality traits, the relationship between laterality and boldness remains inconclusive in sharks. Further studies will prove essential to clarify the mechanisms behind personality traits in vertebrates.

A scalable eigenspace-based fuzzy c-means for topic detection

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Hendri Murfi
Keyword(s):  
Representation Learning ◽  
Detection Methods ◽  
Data Sets ◽  
Topic Detection ◽  
Data Set ◽  
Content Type ◽  
Running Time ◽  
Fuzzy C Means ◽  
Coherence Score ◽  
Value Decomposition

PurposeThe aim of this research is to develop an eigenspace-based fuzzy c-means method for scalable topic detection.Design/methodology/approachThe eigenspace-based fuzzy c-means (EFCM) combines representation learning and clustering. The textual data are transformed into a lower-dimensional eigenspace using truncated singular value decomposition. Fuzzy c-means is performed on the eigenspace to identify the centroids of each cluster. The topics are provided by transforming back the centroids into the nonnegative subspace of the original space. In this paper, we extend the EFCM method for scalability by using the two approaches, i.e. single-pass and online. We call the developed topic detection methods as oEFCM and spEFCM.FindingsOur simulation shows that both oEFCM and spEFCM methods provide faster running times than EFCM for data sets that do not fit in memory. However, there is a decrease in the average coherence score. For both data sets that fit and do not fit into memory, the oEFCM method provides a tradeoff between running time and coherence score, which is better than spEFCM.Originality/valueThis research produces a scalable topic detection method. Besides this scalability capability, the developed method also provides a faster running time for the data set that fits in memory.

scholarly journals Outlier Detection Methods for Uncovering of Critical Events in Historical Phasor Measurement Records

2018 ◽  
Vol 64 ◽  
pp. 08006 ◽  
Author(s):  
Kummerow André ◽  
Nicolai Steffen ◽  
Bretschneider Peter
Keyword(s):  
Power Systems ◽  
Outlier Detection ◽  
Training Data ◽  
Detection Methods ◽  
Data Sets ◽  
Critical Events ◽  
Failure Patterns ◽  
Detection Algorithms ◽  
Reduction Techniques ◽  
Dimension Reduction Techniques

The scope of this survey is the uncovering of potential critical events from mixed PMU data sets. An unsupervised procedure is introduced with the use of different outlier detection methods. For that, different techniques for signal analysis are used to generate features in time and frequency domain as well as linear and non-linear dimension reduction techniques. That approach enables the exploration of critical grid dynamics in power systems without prior knowledge about existing failure patterns. Furthermore new failure patterns can be extracted for the creation of training data sets used for online detection algorithms.

Australian Mammals: Biology and Captive Management

2007 ◽  
Author(s):  
Stephen Jackson
Keyword(s):  
Literature Review ◽  
Artificial Rearing ◽  
Animal Group ◽  
Captive Management ◽  
Educational Publishing ◽  
In The Wild ◽  
Practical Guidelines ◽  
Practical Guidance ◽  
First Time ◽  
Reference Section

This authoritative volume represents a complete and comprehensive guide to the husbandry of Australian marsupials and other mammals. Australian Mammals: Biology and Captive Management dedicates a chapter to each group of animals including the platypus, the echidna, carnivorous marsupials, numbats, bandicoots and bilbies, koalas, wombats, possums and gliders, macropods, bats, rodents and the dingo. For each animal group the following information is covered: Biology; Housing; Capture and restraint; Transport; Diet; Breeding; Artificial rearing; and Behaviour and behavioural enrichment. The book provides a complete literature review of all known information on the biology of each group of animals and brings information on their biology in the wild into captive situations. Also, for the first time, it provides practical guidelines for hand-rearing, and has been extensively reviewed by zookeepers and veterinarians to incorporate the most up-to-date information and techniques. Australian Mammals: Biology and Captive Management provides practical guidance for zoo-keepers, veterinarians, zoologists, researchers and students. Winner of the 2004 Whitley Medal. Shortlisted in the Scholarly Reference section of the 2004 Australian Awards for Excellence in Educational Publishing.

Dive times for foraging dugongs in the Northern Territory.

2001 ◽  
Vol 23 (2) ◽  
pp. 167 ◽  
Author(s):  
SD Whiting
Keyword(s):  
Northern Territory ◽  
Published Data ◽  
Data Sets ◽  
Dive Behaviour ◽  
Direct Observations ◽  
In The Wild ◽  
Observer Effects

THERE are few published studies of dive times of dugongs (Dugong dugon). Direct observations are problematic because D. dugon are shy and difficult to observe in the wild from boats without creating observer effects. Time Depth Recorders (TDR?s) can record dive and surface times during dive behaviour, but there are no published data as yet for D. dugon using this technology. Although studies on dive times using Time Depth Recorders (TDR?s) result in larger data sets, their results are difficult to relate to particular behaviours such as foraging. This paper provides submergence and surface interval times for D. dugon obtained by direct observations in Darwin Harbour. Direct observations, although time consuming, can produce important information related to the ecology of D. dugon.

Sign in / Sign up

Export Citation Format

Share Document