Effectiveness of the eastern grey kangaroo foot thump for deterring conspecifics

2005 ◽  
Vol 32 (7) ◽  
pp. 649 ◽  
Author(s):  
Helena Bender
Keyword(s):  
Background Noise ◽  
Noise Control ◽  
Control Signal ◽  
Wild Populations ◽  
Target Species ◽  
Primary Industry ◽  
Control Signals ◽  
Grey Kangaroo ◽  
Natural Sound

Overabundant wild populations of herbivores often present challenges to primary industry, competing with stock, and damaging crops and property. Eastern grey kangaroos (Macropus giganteus) are one of seven macropodid species that are considered a problem in agriculture in Australia. Most deterrent devices available commercially use sounds that do not occur in nature (i.e. artificial sounds), which often have a short-lived or no effect on the target species, whereas trials with biologically significant sounds are often more effective and provide greater resistance to habituation. I used a playback trial of an eastern grey kangaroo foot thump, a biologically significant signal that is given in response to a predator and is usually followed by flight. I determined its effectiveness compared with a recording of background noise (control) for deterring kangaroos over a seven-week period. Kangaroos significantly increased their vigilance levels in response to the foot thump, but not in response to the control signal. Just over 60% of kangaroos took flight in response to the foot thump and the control signals, but more kangaroos took flight in the first 3 s when the foot thump was played. The foot thump shows potential as a deterrent of eastern grey kangaroos for primary industry, and is less likely to suffer from habituation because it is a natural sound.

scholarly journals Field selectivity of a spinosad-poisoned bait toward target tephritids and non-target insects

2014 ◽  
pp. 11-15 ◽  
Author(s):  
Marco Infusino ◽  
Nino Iannotta ◽  
Stefano Scalercio
Keyword(s):  
Pest Control ◽  
Ceratitis Capitata ◽  
Negative Impact ◽  
Control Strategies ◽  
Field Trials ◽  
Pest Species ◽  
Wild Populations ◽  
Target Species ◽  
Key Points ◽  
Insect Monitoring

One of the key-points in sustainable agriculture is to minimize the amount of pesticides inputs in agro-ecosystems increasing selectivity of active agents on target pests mainly. According to this perspective, control strategies utilising baits receive a growing interest. a spinosad-poisoned sugar-based bait, the so called GF-120 bait, utilised against diptera Tephritidae, recently appeared on the market. The toxicity of spinosad for non-target insects is demonstrated by several authors. However, the amount of pesticide applied is strongly reduced by using it with an attractive food-bait, even if field evidences on the selective attraction of this bait are missing. The aim of this paper is to evaluate the selectivity of GF-120 bait toward target and non-target insects under field conditions, focussing our attention on pollinators. Field trials were performed in a 20 years old olive orchard, where 12 baited and 12 unbaited traps were positioned for insect monitoring. The abundance of the most common orders of insects and target pest species Bactrocera oleae and Ceratitis capitata has been assessed. The main finding of this research is that many pollinators are not attracted by the bait, while target and non-target diptera are significantly attracted by the bait with the exception of Muscidae. The attraction toward a part of non-target diptera should be better explored in order to avoid negative impact on beneficial and non-target species. The need of pest control strategies safer for the environment and the wild populations of non-target organisms seems to be satisfied by the use of this bait.

scholarly journals Digital Watermarks with Adaptive Information Ring Width in the Issue of Hidden Transmission of a Control Signal in the Multi-Target Robotic System

2020 ◽  
Vol 24 (2) ◽  
pp. 136-152
Author(s):  
O. O. Shumskaya ◽  
A. О. Iskhakova
Keyword(s):  
Ring Width ◽  
Digital Watermark ◽  
Robotic System ◽  
Control Signal ◽  
Image Rotation ◽  
Control Signals ◽  
Multi Agent ◽  
Digital Watermarks ◽  
Transmitted Signal ◽  
Hidden Data

Purpose of research. The article is devoted to the issue of ensuring the safe transmission of control signals between the elements of a multi-agent robotic system. The purpose of the work is to provide hidden data transmission with the possibility of unambiguous extraction of control signals.Methods. To solve the task set, an algorithm based on the methods of digital watermarks and digital steganography was proposed. The method of forming a digital watermark in the form of a ring with symmetry allows not only ensuring maximum imperceptibility of embedding (insignificant distortion of the container during concealment), but also to protect the transmitted signal from such complex distortions as image rotation. The steganographic concealment method allows regulating the intensity of embedding using the force factor; it is computationally simple and straightforward. The proposed approach to identifying and understanding the transmitted signal differs from modern methods of cryptography and steganalysis in that it does not require 100% correct signal extraction. After several modifications, the method allows minimizing the time spent on formation (adaptive width of the ring with signal bits) and embedding of a digital watermark (minimization of the processed area of the container for embedding).Results. The proposed approach makes it possible to transmit control signals in a hidden way within the framework of the transmission of digital objects; the conducted experiments have shown that the control signal is unambiguously understood even with such distortions as a decrease or increase in contrast or brightness, image rotation, and compression.Conclusion. Application of the proposed technique for transmitting control signals in a multi-agent robotic system will male it possible to receive the necessary information timely and safe, with a minimum probability of loss.

scholarly journals Optimisation of Energy Use in Bioethanol Production Using a Control Algorithm

Processes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 282
Author(s):  
Jarosław Knaga ◽  
Stanisław Lis ◽  
Sławomir Kurpaska ◽  
Piotr Łyszczarz ◽  
Marcin Tomasik
Keyword(s):  
Energy Consumption ◽  
Pid Controller ◽  
Control Algorithm ◽  
Control Signal ◽  
Control Algorithms ◽  
Signal Quality ◽  
Control Signals ◽  
And Control ◽  
Rectification Process

In this work, the possibility of limiting energy consumption in the manufacturing process of bioethanol to obtain biofuel was analysed. For this purpose, a control algorithm has been optimised while retaining the good quality of the control signals. New in this study is the correlation of the control algorithm not only with the signal’s quality, but also with the energy consumption in such an energy-intensive process as rectification. The rectification process in a periodic production system has been researched. The process was modelled on a test station with the distillation mixture capacity of 25 dm3. For the optimization, the following control algorithms have been applied: relay, PID and PID after modification to I-PD. The simulation was carried out on a transfer function model of the plant that has been verified on a real object, a rectification column. The simulations of energy consumption and control signal’s quality have been carried out in the Matlab®-Simulink environment after implementing the model of the research subject and control algorithms. In the simulation process, an interference signal with an amplitude of 3% and frequency of 2 mHz was used. The executed analyses of the control signal quality and the influence of the control algorithm on the energy consumption has shown some essential mutual relationships. The lowest energy consumption in the rectification process can be achieved using the I-PD controller—however, the signal quality deteriorates. The energy savings are slightly lower while using the PID controller, but the control signal quality improves significantly. From a practical point of view, in the considered problem the best control solution is the classic PID controller—the obtained energy effect was only slightly lower while retaining the good quality of the control signals.

Extracting Initial Iterative Control Signal Based on Trajectory Primitives Matching and Combining

2017 ◽  
Vol 21 (2) ◽  
pp. 228-234
Author(s):  
Jianming Xu ◽  
◽  
Lingxin Kong ◽  
Yaodong Wang
Keyword(s):  
Iterative Learning Control ◽  
Similarity Index ◽  
Control Signal ◽  
Optimal Matching ◽  
B Splines ◽  
Control Information ◽  
Control Signals ◽  
Primitive Sequences ◽  
Definition Of ◽  
Iterative Control

The initial iterative control signal is often adopted a zero or a certain value in the conventional iterative learning control (ILC) system, and an ILC process needs to renew again as long as the desired trajectory is changed. In this paper, the NURBS (Non-Uniform Rational B-Splines) model is used for describing all trajectory primitives and the desired trajectory. It is studied that the problem of the initial iterative control signal is extracted in ILC, which presents a method of extracting the initial iterative control signal based on the trajectory primitive optimal matching and combining algorithm. Firstly, the definition of the similarity index between the two different spacial trajectories is introduced. Secondly, an optimal matching and combining algorithm is designed under a certain similarity index, which is used to find two or more combined primitive sequences with space patterns similar to the desired trajectory. Thirdly, the initial iterative control signals of the desired trajectory are extracted by using the control information of the combined primitive sequences. Finally, the simulation is carried out to demonstrate the effectiveness of the present method.

Coccidia in wild populations of the red kangaroo, Megaleia rufa (Desmarest), and the grey kangaroo, Macropus canguru (Müller)

Parasitology ◽  
1964 ◽  
Vol 54 (1) ◽  
pp. 105-115 ◽  
Author(s):  
R. Mykytowycz
Keyword(s):  
New Species ◽  
Wild Populations ◽  
Free Living ◽  
Red Kangaroo ◽  
Grey Kangaroo ◽  
Two New Species ◽  
Tibia Length ◽  
Clinical Cases

The incidence and prevalence of coccidia have been studied in populations of free-living red kangaroos, Megaleia rufa, and grey kangaroos, Macropus canguru, in four geographically distinct areas in Australia.Two new species of Eimeria—E. wilcanniensis and E. toganmainensis—are described from M. rufa, and five—E. cunnamullensis, E. gungahlinensis, E. purchasei, E. kogoni, and E. hestermani—from M. canguru.The incidence of coccidia ranged from 6 to 14% in populations of M. rufa and from 26 to 70% in M. canguru. The susceptibility of the animals to coccidia was analysed in relation to the tibia length. Red kangaroos with tibia approximately 360 mm. long and corresponding to an age of about 12 months were found to be most susceptible. No clinical cases of coccidiosis were seen in the field.Special thanks are due to the owners or managers of the properties on which the kangaroos were sampled; to members of the staff of the Regional Pastoral Laboratory ‘Gilruth Plains’ for their assistance in sampling, and to Messrs E. R. Hesterman, C. Kogon, and D. Purchase, who assisted in the field and the laboratory. Three species of Eimeria have been named after them in acknowledgement of their work. Messrs B. V. Fennessy and J. H. Calaby of this Division kindly read the manuscript.I wish to thank Dr G. B. Sharman for his permission to work with captive kangaroos in Canberra, and Mr E. Slater who took the photographs.

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