A remote sensing method for the estimation of light-trap efficiency

1988 ◽  
Vol 78 (3) ◽  
pp. 379-385 ◽  
Author(s):  
W. J. McGeachie
Keyword(s):  
Remote Sensing ◽  
Insect Flight ◽  
Light Trap ◽  
Video Camera ◽  
Light Sensitivity ◽  
Trapping Efficiency ◽  
Mercury Vapour ◽  
Trap Catch ◽  
Preliminary Results ◽  
Trap Efficiency

AbstractA description is given of the use of a video camera to estimate light-trap efficiency in the field. This camera relies on the extra light sensitivity provided by the Newvicon detector tube to enable insect track discrimination. Recorded insect flight tracks were classified into three distinct categories, new arrivals, passers by and local flights, the numbers of which were compared to the moth catch in a Robinson mercury vapour light-trap. Calculations of efficiency were made using two methods, the best-estimate efficiency, obtained by comparing the new-arrival tracks to the light-trap catch, and the worst-estimate efficiency, obtained by comparing new-arrival tracks plus passer-by tracks to the light-trap catch. Preliminary results indicate that efficiency varies with windspeed but with a maximum of 39%, obtained in virtually calm conditions, suggesting that some aspect of moth behaviour limits trapping efficiency. It is suggested that the speed of migration of screening pigment from the dark-adapted state to the light-adapted state in superposition eyes may have a bearing on the catching mechanism of a light-trap.

The effects of moonlight illuminance, temperature and wind speed on light-trap catches of moths

1989 ◽  
Vol 79 (2) ◽  
pp. 185-192 ◽  
Author(s):  
W. J McGeachie
Keyword(s):  
Wind Speed ◽  
Multiple Regression ◽  
Light Trap ◽  
Mercury Vapour ◽  
Regression Equations ◽  
Trap Catch ◽  
Mean Temperature ◽  
Mean Wind Speed ◽  
Trap Catches ◽  
Changing Light

AbstractA Robinson 125-W mercury-vapour light-trap was operated at an exposed site near Cranfield aerodrome, south-eastern England. The effects of moon-light, temperature and wind speed on light-trap catch were investigated. The dependent variable, In (catch +1), was compared with the independent variables moonlight illuminance, air temperature and wind speed, using multiple regression analysis. An algorithm was developed and used to estimate moonlight illuminance. Increases in mean illuminance and mean wind speed were associated with a decreased light-trap catch. Increases in mean temperature were associated with an increased catch. When the moth catch was broken down into individual families and species, other trends became apparent. Catches of noctuid moths were unaffected by variation in mean illuminance, although they were influenced by variation in mean temperature and mean wind speed. On the other hand, catches of crambine moths were very sensitive to fluctuations in mean illuminance and mean wind speed although unaffected by changes in mean temperature. The multiple regression equations were used to predict future light-trap catches. The correlations between observed and predicted In (catch +1) for (a) all moths, (b) noctuid moths and (c) crambine moths, were very good. It is suggested that the observed moonlight trend for crambine moths is a consequence of changing behaviour as moonlight illuminance changes rather than the alternative of changing light-trap effectiveness.

Seasonal population changes in cocoa capsids (Hemiptera, Miridae) in Ghana

1968 ◽  
Vol 58 (2) ◽  
pp. 279-294 ◽  
Author(s):  
D. G. Gibbs ◽  
A. D. Pickett ◽  
Dennis Leston
Keyword(s):  
Light Trap ◽  
West African ◽  
Mercury Vapour ◽  
Feeding Sites ◽  
Vegetative Tissues ◽  
Main Crop ◽  
Sahlbergella Singularis ◽  
Dry Conditions ◽  
Seasonal Population ◽  
Direct Counts

Pupulations of the West African cocoa capsids Distantiella theobroma (Dist.) and Sahlbergella singularis Hagl. were sampled in 1966–67 by several methods: fast knockdown over sheets with pyrethrum, mercury-vapour light-trap, direct counts in a small artificially established area of high population, and observations of presence or absence in randomly selected inspection squares.A population build-up in mature cocoa accompanies and probably directly depends on development of the main crop from July or August to October. When pods become scarce after harvesting there is in S. singilaris a period of dispersal in which the species becomes more widespread as feeding is transferred to vegetative tissues, and in D. theobroma a more local change of feeding sites.Subsequent events vary greatly between areas and between years. It is suggested that the extent to which capsids are able to utilise vegetative tissues varies and depends on nutritional changes in the external parenchymatous tissues from which their food is obtained.Low humidities during spells of harmattan in January and February almost certainly kill larvae in exposed situations, but feeding conditions following such periods may be particularly favourable to capsids as large rapid population increases can occur locally. The factors involved are obscure but may be related to processes of regeneration stimulated by leaf loss and other damage in dry conditions.The densities and seasonal patterns found are discussed in relation to results of previous workers and some implications for control briefly considered.

scholarly journals The inelastic scattering of slow electrons in gases.—IV

1933 ◽  
Vol 142 (847) ◽  
pp. 647-658 ◽  
Keyword(s):  
Angular Distribution ◽  
Inelastic Scattering ◽  
Incident Electron ◽  
Angular Distributions ◽  
Mercury Vapour ◽  
Preliminary Results ◽  
Excitation Potential ◽  
Discrete Amount ◽  
Slow Electrons ◽  
Diffraction Effects

Recent investigations have shown that the inelastic scattering of electrons in gases exhibits some very interesting phenomena. In previous papas we have described the angular distribution of the scattering of electrons which have lost a discrete amount of energy. Papers I and II described preliminary results which established the existence of diffraction effects at large angles in a number of gases. In Paper III the measurements were carried out over a range of velocities lower than those previously studied, results being obtained for incident electron energies down to within a few volts of the excitation potential. angular distributions were obtained for the inelastic scattering of electrons in hydrogen, helium, and argon between the angles 10° and 155°. The present paper describes the extension of the measurements to methane, nitrogen, neon and mercury vapour.

Estimating rice water requirements in the Lis Valley (Portugal) using remote sensing platforms: preliminary results for the 2020 cultivation season

2021 ◽  
Author(s):  
Romeu G. Jorge ◽  
Isabel P. de Lima ◽  
João L.M.P. de Lima
Keyword(s):  
Water Management ◽  
Remote Sensing ◽  
Irrigation Water ◽  
Crop Yields ◽  
Irrigation District ◽  
Water Requirements ◽  
Local Conditions ◽  
Preliminary Results ◽  
Sentinel 2A ◽  
Rice Water

<p>In irrigated agricultural areas, where the availability of water for irrigation does not rely on any water storage, water management requires special attention, in particular under large annual and inter-annual variability in the hydrological regime and the uncertainty of climate change. The inherent increased vulnerability of the agro-ecosystem, makes the monitoring of crop conditions and water requirements a valuable tool for improving water use efficiency and, therefore, crop yields.</p><p>This presentation focus on one such agricultural area, located in the Lis Valley (Centre of Portugal), which is a rather vulnerable area also facing drainage and salinity problems. The study aims at contributing to better characterizing the temporal and spatial distribution of rice water requirements during the growing season. Irrigation water sources are the Lis River and its tributaries, which discharges depend directly from precipitation. The most important problems of water distribution in the Lis Valley irrigation district are water shortage and poor water quality in the dry summer period, aggravated by limitations of the irrigation and drainage systems that date back to the end of the 1950’s.</p><p>We report preliminary results on using remote sensing data to better understand rice cropping local conditions, obtained within project GO Lis (PDR2020-101-030913) and project MEDWATERICE (PRIMA/0006/2018). Rice irrigation is traditionally conducted applying continuous flooding, which requires much more irrigation water than non-ponded crops, and therefore needs special attention. In particular, data obtained from satellite Sentinel-2A land surface imagery are compared with data obtained using an unmanned aerial vehicle (UAV). Data for rice cultivated areas during the 2020 cultivation season, together with weather and crop parameters, are used to calculate biophysical indicators and indices of water stress in the vegetation. Actual crop evapotranspiration was appraised with remote sensing based estimates of the crop coefficient (Kc) and used to assess rice water requirements. Procedures and methodologies to estimate Kc were tested, namely those based on vegetation indices such as the Normalized Difference Vegetation Index (NDVI). Results are discussed bearing in mind the usefulness of the diverse tools, based on different resolution data (Sentinel-2A and UAV), for improving the understanding of the impacts of irrigation practices on crop yield and main challenges of rice production and water management in the Lis Valley irrigation district.</p>

Remote Sensing based investigation of secondary mining deformation processes in a postglacial landscape of the Muzakow Arch Geopark (Western Poland) – preliminary results

2021 ◽  
Author(s):  
Jan Blachowski ◽  
Miłosz Becker ◽  
Anna Buczyńska ◽  
Natalia Bugajska ◽  
Dominik Janicki ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Laser Scanning ◽  
Raw Materials ◽  
Ground Level ◽  
Slope Instability ◽  
Opencast Mining ◽  
Ongoing Research ◽  
Preliminary Results ◽  
Underground Workings ◽  
Sink Hole

<p>The area of the present day Muzalkow Arch Geopark located on the border of Poland and Germany was subjected to a long term mining of lignite and other rock raw materials that ceased in the 70’ties of the 20<sup>th</sup> Century. The present-day geomorphological landscape of the research area is characterised by numerous and differentiated forms of anthropogenic origin (e.g. artificial lakes, subsidence troughs, sink holes, waste heaps) associated with underground and subsequently opencast mining of lignite in complex geological and tectonic conditions that result from glaciotectonic processes of subsequent stages of accumulation and weathering. It is thought that the area is presently subjected to geodynamic processes associated with weathering of exposed areas (lignite outcrops and waste heaps), destruction of shallow underground workings (subsidence troughs, sink holes) and changing hydrogeological conditions of the rock mass. The scale of these secondary deformations is presently unknown and these processes pose a threat the present day tourist development of the area, such as: sudden development of discontinuous terrain deformations, slope instability, flooding and subsequent dying of vegetation, etc.<br>Geodetic surveying and remote sensing (terrestrial, aerial and satellite) observations have been employed, apart from other in-situ investigations (geophysical and geological prospecting), to study the processes in one of the former coal mining fields in the geopark.<br>In this study preliminary results of selected geodetic field investigations, i.e. terrestrial laser scanning of a sink hole that showed on the surface in Autumn 2019 and UAV photogrammetric monitoring of an artificial waste rock tips have been reported. It has been found, based on mapping of old mining maps in GIS, that the sink hole is directly related to old shallow underground workings. Maximum depth of the analysed sink hole below ground level is  5.5 m and volume of subsidence is 35 m<sup>3</sup>. The location is being monitored to check if the geometry changes in time.<br>Whereas, comparison of digital elevation models of the investigated waste heap (one of three measured so far) showed development of gully erosion and downward movement of the weathered material. The deposition of material at the bottom of the heap averaged over a dozen cm and maximum of over 50 cm for a half year Summer period (from 15.05.2020 to 07.11.2020).<br>The presented results constitute a first approximation of 3D mapping and modelling the post-mining deformations in glaciotectonic landscape and constitute part of an ongoing research project financed from the Polish National Science Centre OPUS funds (no 2019/33/B/ST10/02975).</p>

A Knowledge-Based Approach for Microwire Casting Plant Control

2011 ◽  
pp. 419-437
Author(s):  
S. Zaporojan ◽  
C. Plotnic ◽  
I. Calmicov ◽  
V. Larin
Keyword(s):  
Continuous Casting ◽  
Casting Process ◽  
Video Camera ◽  
The Other ◽  
Advanced Materials ◽  
Casting Plant ◽  
Preliminary Results ◽  
Sensor Applications ◽  
Knowledge Based ◽  
Main Ideas

This chapter presents the main ideas and preliminary results of an applied research project concerning the development of an intelligent plant for microwire casting. The properties of glass-coated microwires are useful for a variety of sensor applications. On the other hand, the process of casting can be one of the methods of nanotechnology and advanced materials. In microwire continuous casting, the main control problem is to maintain the optimum thermal and flow conditions of the process, in order to fabricate the microwire of a given stable diameter. Unlike a conventional casting plant, we propose to use a video camera to take the picture of the molten drop and to control the casting process by means of a knowledge based system. For this reason, a model, that is capable of taking into account the current features of the process and of describing the shape of the drop at each time, is developed. The model presented here should allow us to estimate the geometry of the metal-filled capillary and predict the diameter of microwire at each time during the casting process.

The Behaviour and Mortality of Anopheles maculatus and Culex fatigans in experimental Huts treated with DDT and BHC

1951 ◽  
Vol 42 (1) ◽  
pp. 1-20 ◽  
Author(s):  
R. H. Wharton
Keyword(s):  
Light Trap ◽  
Trap Catch ◽  
Water Dispersible ◽  
Experimental Huts ◽  
Culex Fatigans ◽  
Large Numbers ◽  
Biting Rate ◽  
Window Traps ◽  
Mansonia Uniformis ◽  
Outdoor Resting

Experimental huts fitted with window traps, of the same basic design as those described by Thomson (1948), modified for Malayan conditions, were used in studying the behaviour and mortality of A. maculatus in relation to DDT and BHC. Other species of Anophelines formed a large proportion of the human bait trap catch but rarely entered the huts.In untreated huts, A. maculatus fed at all hours of the night with a peak between 9 p.m. and midnight. The large majority left before 8 a.m. in search of outdoor resting places, at least 50 per cent. before dawn. It appeared that attraction to light was the strongest, but not the only factor influencing exit from the huts.Large numbers of Culicines (mostly Culex fatigans) were recovered. In untreated huts about 80 per cent. were blood fed ; 28 per cent. were in the window traps.DDT (33 per cent.) and BHC (“ Gammexane P530 and P520 ”) water dispersible powders were tested.An application of 100 mg. DDT and 20 mg. γ BHC (P530) per sq. ft. was unsuccessful, due in part to the small numbers of mosquitos recovered. No conclusions are drawn from the results.DDT at 200 mg. and BHC (P520) at 40 mg. γ isomer per sq. ft. were both effective for at least 12 to 16 weeks against A. maculatus. With DDT, 63 per cent. initial, and 83 per cent. 24-hour corrected mortalities were recorded over 16 weeks. With BHC, though the initial mortality dropped from 100 per cent. in weeks 1–4 to 19 per cent. in weeks 12–16, the 24-hour mortality, almost 100 per cent. for weeks 1–10, was still 88 per cent. for weeks 12–16.DDT apparently had little effect on the feeding of A. maculatus ; with BHC there was a reduction in the percentage fed.DDT was relatively non-lethal to C. fatigans, but had a marked irritant effect driving them into the light trap and the biting rate was reduce to 45 per cent. BHC killed all C. fatigans which entered for 2 weeks but most of its toxic effects were lost by the eighth week. The biting rate was reduced to 27 per cent. for weeks 1 to 8 and the majority of mosquitos were recovered in the light trap.Ants, cockroaches, spiders, etc., were found to affect the number of mosquitos recovered and special precautions had to be taken against losses.The results suggested that BHC when freshly applied acts as a repellent to mosquitos.Mansonia uniformis was shown to be susceptible to both DDT and BHC residual deposits.

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