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Efficiency - Printable Version +- Blitzortung.org Forum (https://forum.blitzortung.org/mybb) +-- Forum: Public Forums (https://forum.blitzortung.org/mybb/forumdisplay.php?fid=29) +--- Forum: General Discussion (https://forum.blitzortung.org/mybb/forumdisplay.php?fid=31) +--- Thread: Efficiency (/showthread.php?tid=1261) |
RE: Efficiency - micha.d - 2017-10-26 Thanks for the answers. I'll only respond to the things related to efficiency. (2017-10-23, 21:30)orion_jb2001 Wrote: Interesting fresh observations. The automatic feature of this TOA system has never, I don't think, been fully utilized. . Well that's an argument for optimizing the auto as well, not only the efficiency display.Isn't it possible to distinguish repeated and sporadic signals. All the repeated are noise. If really many station go for auto, then that might be a quick win. (2017-10-24, 01:04)allsorts Wrote: It's certainly possible but you'd have to be really vicious with the filters. Due to a couple of VLF transmitters within 30 odd miles I have the lo-pass option fitted and set to 17 kHz. Still have plenty of signals used by the system. That's a pretty good info. That gives me a good feeling that the noise can be managed. It's hard to find that out through the efficiency display. At least I did not make it so far. (2017-10-24, 01:04)allsorts Wrote: If you are logged into LMO and viewing your station the Archives > List gives distance direction and number of participants. What I have not see it show is if a given signal was used. There is a "Participated" field but I've never seen it. Well, I don't see the mentioned data in one source, maybe I missed something. Either it's all stations (not just mine) or I don't get the "used" flag for my station. I thought about writing a tool that downloads all the stats but all that requires effort and is only usable locally in the end. I would want to pimp the display for all members. (2017-10-24, 06:00)readbueno Wrote: This is a good tool for helping to find a good balance, between signals sent and strokes recorded. I like this one, but it's also a "slow" efficiency marker like all the others. But again we could take some lessons learned out of it. Close to the diagonal is good, far away is bad. I think that is a part of the current calculation already. (2017-10-26, 21:03)Egon Wrote: I would like to change the measure for the efficiency of the stations. It may not be appropriate to calculate only one numerical value, but rather to introduce different possibly even competing measures for the efficiency of the systems. Ok, this is maybe only a starting point, but what would have helped me in the beginning is an advice what to change. Let's do some examples:
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RE: Efficiency - readbueno - 2017-10-26 Hi Egon, Stations should maybe be weighted as to how useful the signals are that they send to the server? If there are only 20 stations that locate a stoke is that data more valuable than when 350 stations receive the same stroke? Is a stroke recorded at 200 km as useful as one at 1200 km or 4500 km? At present the effectivity of a station is heavily biased towards distance, Effectivity L. Would it be more efficient to base the stations position on their shorter and medium effectivity? Could there be some explainable scientific basis for these measures? Many stations appear to have a very poor signals sent to strokes recorded ratio. I have noticed this as over 75,000:1 in some cases, these stations still appear higher in the lists than stations with more even ratios. Should Detecting stations whose signals are actually used in the calculations for the location of the stroke be worth more than a station that detects the stroke, but is not one on which the calculation is based. Should stations in less densely populated parts, Blitzortung wise, get a premium for detecting strokes in relation to the area that they are trying to cover, i.e Coastal stations or stations that by their position cover mainly underpopulated areas? The Pacific Ocean area, Asia, Africa and South America spring to mind and Micha's new station for India? Looking at the archived data for stations participating in the detection of a stroke, there seems to be a large variability in the quality of the signals sent, not only between greens, reds, and blues, but even between stations of the same groups. Should there be some measure of the "quality of signal" sent to the server? Signal to noise ratios? Index of Distortion? I am sure that others may have better ideas, I shall sleep on this and maybe add more tomorrow. Kindest regards, Brian.
RE: Efficiency - pasense - 2017-10-27 This thread mixes several problems, I will try to seperate them:
My comments are: For 1.): assuming the station doesn't have internal noise (suitable power supply, shielded/ unshielded cables, well placed antennas) only external noise counts. If you cannot identify and eliminate noise sources, there are only two options: if the frequency of the noise sources is higher than say 15 kHz use the LP filters and set the cutoff frequency accordingly; if not, lower the amplification and/ or raise the threshold. For 2.) Egons suggestions are good, but what about a quality measure for the signal used in calculations? For stations within the network (but ONLY for them), this appears to be a good indicator: https://www.meteomelin.be/staticfiles/bl...egion=1&id= In the case of the few stations contributing to more than one region the regions should be combined in the efficieny measure, but if the regions are going to disappear anyway, this may not be required. For 3.) Stations within the network (surrounded on all sides by other stations within a reasonable distance) need to be treated differently from stations at the fringe of the network like coastal stations or even completely isolated stations (on islands, isolated towns...) Maybe one could calculate a measure that indicates the integration or isolation of a station? From the experiency of the other network that operates globaly (http://wwlln.net/) I would suggest to install the LN filters directly on the board since soldering the tiny ICs afterwards is really difficult. Wwlln uses a cutoff of 22 kHz since most of the sferic signal strength is below this frequency. If bought in quantity the cost of the LP filters is acceptable and the added flexibility in handling noise and improving S/N ratio is well worth it. RE: Efficiency - readbueno - 2017-10-27 Hi All, We need to define what we each mean by "efficiency" and agree on a common definition? In the case of:- https://www.meteomelin.be/staticfiles/bl...egion=1&id= Would it be possible to develop this tool slightly more and have an average accumulated total for various longer periods, updating every five minutes and only giving the results for the last hour, whilst very useful, does not go far enough. One day, One week, One month? This need not be "real-time" for the historic data and would show the affects over time, especially if several graphs could be seen on the same screen at the same time for comparison. This "pattern" might also help with the station stats pages, i.e. more variable periods of time rather than just the last 24 hours, or the total stored data since the station started. This would help in "optimising" our stations and reduce the overall load on the servers. A better explanation of how the auto functions work, some basic instructions and improving their working, would make it easier for people who do not have a lot of time to fully monitor and manage their stations? Information and education should be part of running a station, if we don't know what we are doing, or what the overall aim of the network is, then different stations are going to have different goals and this will lead to less network efficiency. Maybe the LP filters could also be managed by the server to allow for wider bandwidth at times of low noise? I know that I have maybe drifted off the main topic of "Efficiency," but surely these and some of the other suggestions made in these recent posts are inter-related. Brian.
RE: Efficiency - Breitling - 2017-10-28 (2017-10-27, 09:15)readbueno Wrote: Hi All, We need to define what we each mean by "efficiency" and agree on a common definition? Nice graph. I would add some reference lines for a better interpretation: RE: Efficiency - readbueno - 2017-10-28 Hi Luis, Yes I like that Idea. No-one is going to get near 100%. As we see, most stations are between your yellow and the black lines, that seems to be the "reasonable" area, although that should not discount stations in that area trying to improve! The area to the right of the black line should be an indication that these stations are not working as well as they should/could, and that an effort should be made to improve this situation. The nearer you get to the bottom right hand corner the more opportunities for improvement are open to you? These stations are your Blitzortung neighbours, you should help, them just as you do your physical neighbours, when they need help. Maybe the actual points could be made different colours to show the "health status" of the stations? Brian.
RE: Efficiency - Breitling - 2017-10-28 (2017-10-28, 08:52)readbueno Wrote: Maybe the actual points could be made different colours to show the "health status" of the stations? Maybe, or showing "online time percentage" if it is possible to read automatically. RE: Efficiency - cutty - 2017-10-28 (2017-10-26, 21:03)Egon Wrote: Hi Folks,Just brainstorming: Suppose we explore this, for each unique station, as opposed to, or in addition to, station's relative "Network / Region" performance. This suggestion is for 'Typical" installations. It's my belief that a second group might be considered, for example, those stat1ons that are 'purposefully' employed across regions or oceans. However they, I believe, should be "qualified" on Efficiency and Effectivity overall before being placed into that group. And 'disqualified' if performance degrades. If makes little sense to me to have a station with a noisy environment attempting to serve 'cross region' or ocean, for example. We define: Goal: detect maximum number of strokes accurately with minimum number of signals Efficiency: Ability to accomplish something with the least amount of time and effort. Effectivity: Actual production of the intended result. Efficiency = Strokes Detected / Signals Sent Effectivity = Strokes Detected / Signals Sent - Strokes Detected examples: Station: 200 strokes with 1000 signals sent: Efficiency = 200/1000=20% Effectivity = 200 / (1000-200) 800 = 25% Station: 200 stokes with 500 signals sent: Efficiency = 200/500=40% Effectivity = 200 / (500-200) 300=67% Station: 800 stokes with 2500 signals sent: Efficiency = 800/2500=32% Effectivity = 800 / (2500-800) 1700=47% That is, a station which sends a lot of signals, but few strikes is not very efficient. For Effectivity; some of the 'signals' sent ARE strikes, and they are removed from the Total Signals, then strikes compared to 'remaining' (unused" signals. Mike RE: Efficiency - readbueno - 2017-10-28 Hi Cutty, How does this look in your scheme of things. I am the third black dot a little to the right, yours is the top black dot and another Mike is just a little to the left of my dot. Whilst I feel that I have, even yet, considerable "headroom" for improvement, my station appears to work quite efficiently when there is Lightning to report and sends very few signals when there is not. I presume that some of those signals at least are "Housekeeping" between the station and the server? Rather than just wastage. As a European coastal station added to Region 3, I feel that the benefit to both regions when there are storms in the North Atlantic are significant. Maybe more coastal stations would consider this option in various situations? I am also considering, some time over the winter, to have a dedicated antenna, with which to assist, if possible, the new stations in Africa. As nearly three-quarters of my horizon is ocean it should be possible to "null" out most of Europe by careful positioning of the antenna, I was thinking of a single three turn Mobius type, and for this specific example, a certain amount of Dxing would be legitimate and beneficial to the development of the Network. This use of a deeply nulled single antenna could be of use in various other situations as well? Regards. Brian. RE: Efficiency - pasense - 2017-10-28 We need to look at the signal/ noise ratio from stations first. Noise here means signals not from real strokes. I just used the strikes/ signals plot and then the stations list to check the signals from some of the stations in the right bottom area, where the stations are concentrated that have low "efficiency". I have not made a complete investigation, but a high percentage of them (but not all) clearly has a serious noise problem. Often this is noise with a frequency larger than 25 kHz. A lot of the signals are so terrible that I doubt that the owner of the station has looked much at them, or if he has, he is not able to interpret what he sees. Obviously, these stations are not contributing to the network. Identifying these stations has to be done by hand so it would take some time, but then the owners could be contacted and advised to improve the performance. If they don't, their signals could be ignored directly. Another conclusion I would draw: increasing the number of stations without attacking this problem at the root is not advisable. |