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Energy measurements with the GDV Eco Tester.
Energy measurements on McLeod Island in the Andaman Sea
with the GDV Eco Tester.
I and my wife Irina saw the New 2012 year in on a sandy beach under the tropical sun on a small McLeod Island in the Andaman Sea. (Nabucco's Myanmar Andaman Resort, Macleod Island, Mergui Archipelago, e-mail: myanmar@extradivers.info). It was our second visit to this wonderful place; in 2011 we were so enchanted by the beauty and silence of this island that we decided to return there by all means, which we did the next year. There is a small resort for divers on this island, and every morning all active “population” got on a small bark and went to dive to the nearest reefs each of which features its own underwater world. The most part of day the island is absolutely deserted, you can walk on sandy beaches, dive from a “home” reef, or to walk in jungle. What else is necessary for good rest!
On the island almost every day I made measurements with the GDV Eco Tester. And the very first result in the evening on January 1st was surprising! The signal increased almost all time during measurements for more than 8 hours (fig. 1, curve 1).
Fig.1. Time signal dynamics of Eco Tester on McLeod Island 1-7.01.2012.
1 – January 1, 7 pm; 2 – January 2, 1 am; 3-7 – January 2-6; 8 – January 7, 6 pm.
(Calculation principles are presented in Appendix 1).
At night I repeated measurements: the result was the same (fig. 1, curve 2). But the next morning the situation cleared up: we woke up from the noise of a tropical downpour which proceeded without interruption till evening. It was unusual for January, but all the year round in 2011 the weather in the world was unusual. The next day the sky was gloomy since morning, even some raindrops fell down, but by evening it started to clear up. I began measurements at 5 pm; the signal was increasing for some time, and then reached its saturation. That level remained all the following days (fig. 1, curves 3-7). At night the sky was almost clear, with the moon growing bigger. On January 7th a strong wind started blowing, the sea disturbed, and the full moon shone from the sky. The amplitude of signal that day decreased a little (fig. 1 curve 8). Interesting observations follow from the analysis of variability of a signal. (Calculation principles are presented in the Appendix 1). Apparently from fig. 2 and 3, on January 1st variability was high, on the next days – 1-2 %.
Fig.2. Time dynamics of signal variability on McLeod Island 01.01.2012.
Fig.3. Time dynamics of signal variability on McLeod Island 3-7/01.
For comparison, fig.4 shows a graph of data variability of Eco Tester in Saint Petersburg in November 2011. As it is seen, in quiet conditions and in good place variability is about 1%.
Fig.4. Time dynamics of signal variability in Saint Petersburg.
The presented data confirm the sensor sensitivity showing however the dependence of data both on the energy of the place of measurement and the state of atmosphere. For example, on McLeod Island the sun sets very rapidly which shows in the area and intensity graphs (fig. 5, 6).
Fig.5. Time dynamics of signal variability on McLeod Island 2/01.
The arrow shows approximate time of sunset.
Fig.6. Time dynamics of signal intensity on McLeod Island.
The arrow shows an approximate time of sunset.
Energy measurements in Cambodia.
After Myanmar we flew to Siem Reap in Cambodia where a few ancient architectural complexes are situated. Most of them are protected by UNESCO; millions of people visit these places annually.
As we know from our experience, it makes no sense to carry out measurements in the places with crowds of tourists since human energy fields may have stronger influence than the place itself. Therefore I was glad to find Preah Palilay Temple inside Angkor Tom Complex situated away from the main tourist routes. We rode there on bikes (fig.7).
Fig.7. Map of Angkor Tom Complex with marked Preah Palilay Temple.
For comparison there are measurement data obtained in a hotel situated at a distance of about 10 km from the Complex. Once I managed to take measurements near the Buddhist Temple where a morning ceremony was taking place at that time. See the results in fig.8.
Fig.8. Time dynamics of Eco Tester data in Cambodia.
As you can see from the graphs, the results in Preah Palilay Temple significantly differed from other measurements both in energy and in signal variability. It seemed as if the signal was of an unknown origin.
Interesting data were obtained near the Buddhist Temple: the signal energy is not very high; however, the variability is the same as in Preah Palilay Temple.
Unfortunately, we had no time to repeat measurements, but the obtained data show the importance of such studies, thus we hope that they will be continued by our colleagues.
Coming over to glow energy units in GDV-graphy.
As it is shown in [1], the CCD matrix sensitivity is defined by the following expression :
where W – is the glow energy density of the source [J/сm2], I – the response (signal) value [point], E – the glow energy of the source [J], s – the area of the part of the CCD matrix illuminated by laser radiation [сm2], P – the power of the radiation source [W], t – the time of exposure set on the camera [sec], T – the total coefficient of light filter transmission used during the recording of glow, d – the diameter of the part of the CCD matrix illuminated by laser radiation [сm].
It was experimentally determined that sensitivity decreases with the wavelength increase, and for Λ= 424 nм it has the order of 10-10 J/cm2 both for laser and for incandescent lamp.
Naturally, this parameter depends on the CCD type and the used optical path. Therefore an experimental study of the response parameters of the CCD matrix used in GDV devices was carried out using an incandescent lamp with known parameters. A matted 10 W lamp was used providing a relatively even light flow in the visible region.
For that lamp illumination of the CCD matrix corresponded to the area S = 61000 pixels with spectrum from 55 to 255, with maximum at 160 and average at 220.
Hence, the equivalent source power can be calculated as
P (W) = S*I*/61000*200*10 = S*I*8*10-9A GDV image of a finger of a healthy person has the parameters S = 10000 pxl, Iaver = 80 => P = 64 mW. A GDV image of a finger of a sick person has the parameters S = 4000 pxl, Iaver = 60 => P = 1,9 mW.
Energy Е (J) P (W) / t (sec)GDV pulses with duration 10-4 are generated with frequency 1000 Hz during 0.5 s. Thus the time of signal accumulation on the CCD matrix is 5*10-2 s, откуда Е = 20 Р. whence it appears that Е = 20 Р. For the above cases it will be 1.28 J and 0.38 J, respectively. Thus, the formula for the glow energy of a GDV signal has the following form:
Е (J) = S*I*1,6*10-6For simplicity of calculations we assume
Е (J) = S*I*2*10-6The use of this formula enables to represent both the processing results of GDV images, and dynamic data in the units of glow energy.
Variability of the dynamic curve can be evaluated as follows:
V(tk) = St.Dev X(tk-20 to tk) / Xaver ,where V(tk) – is variability of X parameter at tk moment; Xaver –the average by X in some interval (constant).
This equation means that we take the Standard Deviation of 20 points preceding the given point, which corresponds to 100 s with the interval between the points being 5 s. This time was chosen after the analysis of a large series of experiments. In some cases it is convenient to use variability, and sometimes the Standard Deviation.
Appendix 2
Angkor Tom Temples, Preah Palilay Temple
Measurement process with GDV Eco Tester.
Ta Prohm Temple, At the Buddhist Temple.
Reference
B.L.Vasin, S.V.Malkova, M.V.Osipov, V.N.Puzyryov, A.T.Saakjan, А.Н. Starodub, S.I.Fedotov, A.A.Fronja.
A measurement technique of spectral sensitivity of CCD matrix. P.N.Lebedev Physical institute of the Russian Academy of Sciences, Moscow, Preprint 18, 2007 (in Russian). http://ellphi.lebedev.ru/20/pdf18.pdf