FIELD TEST OF AN AUTOCIDAL CONTROL METHOD WITH THE FERAL MOSQUITO CULEX RESTUANS (DIPTERA: CULICIDAE)

1975 ◽  
Vol 107 (5) ◽  
pp. 465-470
Author(s):  
G. K. Bracken ◽  
M. G. Maw

AbstractAn autocidal control method involving attraction of ovipositing females to artificial oviposition sites, rearing and chemical sterilization of adults reared from the collected eggs, and release of sterilized males back into the system was field tested with the mosquito Culex restuans Theobald. This species cannot be cultured continuously. The average weekly percentage of sterile egg rafts was 2.4 (range 0.3–16.0) in the test area where sterile males were released (av. 9620/wk) and 5.3 (range 1.5–30.0) in the area where both sterile males (av. 7000/wk) and untreated females (av. 4590/wk) were released. The low level of sterility achieved is attributed to infiltration of gravid females from outside the experimental areas, poor efficiency in producing sterile males from the collected egg rafts, and the small scale of the test.A hypothetical model is used to compare theoretical reduction in rates of increase of a population of mosquitoes when various proportions are induced to oviposit in ‘trap’ pools if the eggs trapped are destroyed, reared to produce sterile males for release, or reared to produce sterile males for release in conjunction with larvicidal treatment of uncontrolled breeding areas.

2019 ◽  
Author(s):  
Yevhen Holubnyak ◽  
Willard Watney ◽  
Tiraz Birdie ◽  
Dana Wreath ◽  
George Tsoflias ◽  
...  

2014 ◽  
Vol 39 (3) ◽  
pp. 232-237 ◽  
Author(s):  
Bryce Dyer

Background/Objectives: This study introduces the importance of the aerodynamics to prosthetic limb design for athletes with either a lower-limb or upper-limb amputation. Study design: The study comprises two elements: 1) An initial experiment investigating the stability of outdoor velodrome-based field tests, and 2) An experiment evaluating the application of outdoor velodrome aerodynamic field tests to detect small-scale changes in aerodynamic drag respective of prosthetic limb componentry changes. Methods: An outdoor field-testing method is used to detect small and repeatable changes in the aerodynamic drag of an able-bodied cyclist. These changes were made at levels typical of alterations in prosthetic componentry. The field-based test method of assessment is used at a smaller level of resolution than previously reported. Results: With a carefully applied protocol, the field test method proved to be statistically stable. The results of the field test experiments demonstrate a noticeable change in overall athlete performance. Aerodynamic refinement of artificial limbs is worthwhile for athletes looking to maximise their competitive performance. Conclusion: A field-testing method illustrates the importance of the aerodynamic optimisation of prosthetic limb components. The field-testing protocol undertaken in this study gives an accessible and affordable means of doing so by prosthetists and sports engineers. Clinical relevance Using simple and accessible field-testing methods, this exploratory experiment demonstrates how small changes to riders’ equipment, consummate of the scale of a small change in prosthetics componentry, can affect the performance of an athlete. Prosthetists should consider such opportunities for performance enhancement when possible.


2020 ◽  
Vol 2020 ◽  
pp. 1-13 ◽  
Author(s):  
Changxi Ma ◽  
Jibiao Zhou ◽  
Xuecai (Daniel) Xu ◽  
Jin Xu

To understand the status quo of urban recurrent traffic congestion, the current results of recurrent traffic congestion, and gating control are reviewed from three aspects: traffic congestion identification, evolution trend prediction, and urban road network gating control. Three aspects of current research are highlighted: (a) The majority of current studies are based on statistical analyses of historical data, while congestion identification is performed by acquiring small-scale traffic parameters. Thus, congestion studies on the urban global roadway network are lacking. Situation identification and the failure to effectively warn or even avoid traffic congestion before congestion forms are not addressed; (b) correlation studies on urban roadway network congestion are inadequate, especially regarding deep learning, and considering the space-time correlation for congestion evolution trend prediction; and (c) quantitative research methods, dynamic determination of gating control areas, and effective countermeasures to eliminate traffic congestion are lacking. Regarding the shortcomings of current studies, six research directions that can be further explored in the future are presented.


2011 ◽  
Vol 347-353 ◽  
pp. 3555-3558
Author(s):  
Peng Zhao ◽  
Wen Yi Li ◽  
Xuan He ◽  
Xin Yao ◽  
Yin Sha Wang ◽  
...  

Aims at the small wind generations output voltage fluctuation problems, according to the characteristics of permanent magnet synchronous generator, by the vector control methods, in MATLAB/Simulink lans established permanent magnet synchronous motor current speed 2-ring vector control simulation model. Simulation results show that, the method can improve the small wind turbine output voltage stability.


Author(s):  
Kazuhiko Hiramoto ◽  
Taichi Matsuoka ◽  
Katsuaki Sunakoda

Abstract We propose a new active vibration control strategy based on the future seismic waveform information obtained in remote observation sites. The waveform information in the remote site is transmitted by a waveform transmission network to the structure under control. The waveform transmission network is realized by interconnecting multiple controlled structures and observation sites. By using the future waveform information obtained through the network, we propose a control law realizing fairly higher control performance over the conventional structural control methodologies. A preview control law consisting of the state-feedback and feedforward control (preview action) is adopted. For the preview action, future values of the disturbance in some time interval are necessary. However, because the future value of the earthquake waveform is unknown, the preview action contributing the performance improvement is generally impossible. To get over this difficulty, an AI-based wave estimation system to estimate the future earthquake waveform is proposed. The wave estimation system is a multi-layered artificial neural network (ANN). Through a small scale simulation study with a recorded earthquake event in Japan, we show that the proposed control method achieves much higher control performance over the conventional LQ-based active control.


1978 ◽  
Vol 56 (1) ◽  
pp. 75-79 ◽  
Author(s):  
Gordon Pritchard

Extraction of eggs of Dacus tryoni from fruit was aided by first identifying oviposition sites with a water-soluble dye and then digesting the fruit tissue around the oviposition site with a mixture of enzymes consisting of equal parts of 1% pectinase and 1% cellulase. The numbers of eggs laid per week were estimated by a formula that incorporated the numbers of hatched and unhatched eggs present on one occasion each week, the proportion of fertile eggs in each variety of fruit, and the development time of eggs.Many more eggs were laid in an orchard in New South Wales, Australia, in a wet year (1966–1967) than in a dry year (1965–1966). This was due in part to a larger population of adults that migrated into the orchard in the wet year and to the fact that fruit remained on the trees longer. There was evidence that the rate of oviposition in the wet season fell off as fruit became scarcer towards the end of the season. Aggressive behaviour of females on fruit and movement of gravid females away from the orchard are possible explanations.


Author(s):  
G.B. BURDO ◽  

Presents the approach to dispatching the work of mechanical processing technological divisions of machine-building single and small-scale multi-product production plants. Algorithms for technological processes dispatching based on the fuzzy control method are shown. Input and output fuzzy variables are defined and their membership functions are shown. The control algorithm is given in the form of fuzzy rules. An example of the algorithm implementation is shown.


1999 ◽  
Vol 124 (1) ◽  
pp. 191-195 ◽  
Author(s):  
Hongliu Du ◽  
Satish S. Nair

The dynamics of a booster station, which is critical for the control of a novel, long distance, hydraulic capsule pipeline, is simulated mathematically for design studies and control of the hydraulic transients caused by the valve actuators in the system. Several modifications to the pump bypass station configuration of the booster station have been studied. With the objective of eliminating column separation and reducing flow reversals, a configuration with several centrifugal pumps connected in series, and a carefully sized air chamber is found to be a viable design. A valve control method is designed to eliminate column separation and the design results in acceptable flow reversal levels in the main pipe. The simulation results match with trends in limited experimental studies performed on a small scale experimental capsule pipeline system.


2010 ◽  
Vol 47 (4) ◽  
pp. 657-663 ◽  
Author(s):  
Tamara S. Ball ◽  
Scott R. Ritchie

Abstract The BG-Sentinel (BGS) trap uses visual and olfactory cues as well as convection currents to attract Aedes aegypti (L.). The impact of the visual environment on trapping efficacy of the BGS trap for Ae. aegypti was investigated. Four- to 5-d nulliparous female and male Ae. aegypti were released into a semicontrolled room to evaluate the effect of the presence, reflectance, and distribution of surrounding harborage sites on BGS trapping efficacy. Low-reflective (dark) harborage sites near the BGS had a negative effect on both male and nulliparous female recapture rates; however, a more pronounced effect was observed in males. The distribution (clustered versus scattered) of dark harborage sites did not significantly affect recapture rates in either sex. In a subsequent experiment, the impact of oviposition sites on the recapture rate of gravid females was investigated. Although gravid females went to the oviposition sites and deposited eggs, the efficacy of the BGS in recapturing gravid females was not compromised. Ae. aegypti sampling in the field will mostly occur in the urban environment, whereby the BGS will be among oviposition sites and dark harborage areas in the form of household items and outdoor clutter. In addition to understanding sampling biases of the BGS, estimations of the adult population size and structure can be further adjusted based on an understanding of the impact of dark harborage sites on trap captures. Outcomes from this suite of experiments provide us with important considerations for trap deployment and interpretation of Ae. aegypti samples from the BGS trap.


2005 ◽  
Author(s):  
Helio Mauricio Santos ◽  
Paul Ian Reid ◽  
Julian Leigh Jones ◽  
John McCaskill

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