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No. 14/2024 (April 1, 2024)
The security of the 2024 Olympic and Paralympic Games in Paris will be ensured by artificial intelligence.
An artificial intelligence-assisted video camera system was tested during a concert by British band Depeche Mode in Paris in early March 2024. Although the technology has been controversial among Paris residents and human rights activists, it passed the test and will be implemented during the 2024 Olympic and Paralympic Games in Paris. French legislation passed in 2023 authorizes the use of artificial intelligence-based video surveillance during a trial period covering the Games to detect unusual events or human behavior during large-scale events. Officials say the technology could play a key role in preventing an attack such as the 1996 Atlanta Olympics bombing or the 2016 Nice truck attack.
Algorithmic video surveillance uses computer software to analyze images captured by video surveillance cameras in real time. Algorithms are trained to detect predetermined "events" and unusual behavior and send alerts accordingly. Humans then decide whether the alert is real and whether it should be acted upon. Software enabling AI-based video surveillance can easily enable facial recognition. It is simply a configuration choice. The new law still prohibits facial recognition in most cases, and French authorities have said it is a red line that should not be crossed.
AI-based surveillance will be available to national and local police, firefighters and public transportation security agents. The AI software, which uses algorithms to analyze video streams from existing video surveillance systems to identify potential threats in public spaces, was developed by 4 companies: Videtics, Orange Business, ChapsVision and Wintics.
Efficient computer network.
A 10 Gbps network is a computer network that allows data to be transmitted at speeds of up to 10 Gbps. A backbone network with such high bandwidth is used in large enterprises, data centers and research laboratories. It allows large amounts of data to be exchanged in a short period of time which is especially important for applications such as cloud computing, high-quality video transmission or transferring large amounts of scientific data.Below is an example of a computer and WiFi network with a 10 Gbps backbone. The network is built with a router and three different network switches. The first switch is TP-Link TL-SX3008F 8xSFP+, which is the most important device in the network. It is the one responsible for switching packets (the packet forwarding rate for this device is 119.04 Mp/s) with a total throughput of 160 Gbps. Two switches are connected to this device via optical ports - one is responsible for connecting access points, while the other is responsible for connecting computers and other network devices.
WiFi network based on a 10 Gbps backbone.
Measurements in fiber optic systems. Part 2.1 – transmission method measurement – basic test of a fiber optic link.
Measurement using a light source and optical power meter in accordance with PN-EN 61280-4-2 or ISO/IEC 14763-3:2014 is the basic way to verify the correctness of a fiber optic link. It can also form the basis for network certification for specific applications.The idea behind the transmission method of measurement is simple - to the completed fiber-optic connection, usually terminated on both sides in switches, boxes, etc., is connected a light source of known power on one side, and an optical power meter on the other. Test patchcords are used when connecting the devices.
The idea of measuring by transmission method.
Knowing the power of the light source that injects the signal into the optical fiber and reading the power on the optical power meter, one is able to determine how much of the source power has been precipitated, or in other words, what is the attenuation of the connection made. Most available light sources generate power at -5 dBm. If a power meter connected on the other side reads -8 dBm, for example, this will mean that the attenuation of the measured line is 3 dB.
However, performing a measurement as above, without the so-called zeroing procedure of the measurement system, is subject to a very high uncertainty and cannot be treated as a reliable measurement. The uncertainty of the measurement is due to several issues. The most important include:
- uncertainty related to the power of the source: the power level value of -5 dBm declared by the manufacturer may in fact be different; ignoring the issues of warming up the device before the measurement (it should take 15 - 20 minutes), these devices may generate power slightly different from the declared one;
- uncertainty related to the attenuation of the light source connector: when connecting the measurement patchcord to the light source, we generate additional signal attenuation of unknown value - the light source connector is the one that generates loss. This is due to the design and construction of the device itself;
- uncertainty related to the attenuation introduced by measurement patchcords: when measuring using measurement patchcords, their attenuation is taken into account in the final result. Since these patchcords are not part of the measured path and the value of the attenuation contributed by them is unknown (in the extreme case it could be a significant part of the total), they should not be taken into account in the measurement.
To reduce measurement uncertainty, measurement standards PN-EN 61280-4-2 and ISO/IEC 14763-3:2014 prescribe a procedure called system zeroing, also known as measurement system calibration or reference measurement (performed with reference to another value). There are 3 methods of system zeroing: the 1 patchcord method, the 2 patchcord method, and the 3 patchcord method. They all involve the same thing - connecting the light source and the power meter with a measuring patchcord or patchcords, and then saving the obtained power as a reference value for the next measurement, which will already be the actual measurement on the made line. The name "system zeroing" refers to the fact that, as a rule, after connecting the devices with the measurement patchcord/patchcords, the user presses the "REF" or similar button on the meter, which ends up storing the currently read power in the device's memory and displaying a value of 0 dB on the meter's screen. From now on, anything plugged in additionally between the devices (in particular, the line you want to measure) will generate additional attenuation, which will be directly displayed on the meter's screen. The idea of zeroing the circuit with each of the three methods is presented below.
Transmission method measurement: circuit zeroing - 1-patchcord method.
Transmission method measurement: circuit zeroing - 2-patchcord method.
Transmission method measurement: circuit zeroing - 3-patchcord method.
After zeroing the circuit, unplug the devices, and then connect them to the switches to measure the attenuation contributed by the made line. When doing so, do not unplug the patchcord from the light source, since connecting and disconnecting the plug at this point generates slightly different attenuation values each time.
Consider the example from the beginning of the note, in which the attenuation of the measured line without resetting the circuit was 3 dB. Suppose the same line is measured now, but preceding the measurement by zeroing the circuit using the 2 patchcord method. Connecting a source with a claimed power of -5 dBm to the meter using 2 patchcords and an adapter, a power indication of -6 dBm is obtained on the meter. It follows that the meter patchcords contribute 1 dB of attenuation. In fact, it is not quite clear how much attenuation the patchcords themselves contribute, because we still cannot be sure about the declared power of the source (if the source would generate a signal of -5.2 dBm, the attenuation of the patchcords is 0.8 dB), but nevertheless it is not important at this point. What is important is the measurement we make in the second step - in reference to the power value stored in the meter (in this case -6 dBm). The circuit is zeroed by pressing the REF button. After resetting the circuit, you connect the equipment to the measured line and get a value of -2 dB on the meter screen. There is a measured value of line attenuation stripped of the measurement uncertainties described above.
Each of the three methods of the measuring system zeroing, due to the use of a different number of patchcords in determining the reference power, will ultimately generate a slightly different measurement result. So which one should be chosen? Intuition here usually suggests the method of 2 patchcords, since that is the number used in the final measurement. However, it turns out that this method is less accurate than the 1-patchcord method, and it is 1 patchcord that should be used when zeroing the circuit whenever possible. Why? We are going to write about it in the next issue of the Weekly Review, comparing the results generated with the support of both methods. We will also give some practical remarks related to the interpretation of the results obtained.
Installation of TERRA MR-9xx series radial multiswitches in a RACK cabinet.
The RACK board ZMD-1 R77311 front mounting assembly is a set of two brackets for mounting in a RACK cabinet. It has dedicated holes for mounting of TERRA MR-xxx multiswitches (hole spacing: height 120 mm, width 100/140/180 mm). The M5x10 bolts and nuts are included. The vertical spacing of the elements is chosen so that the cables connected to the multiswitch input connectors have enough space to maintain the minimum bending radius. It is even possible to install Signal R48602 surge protectors. The set includes eight screws with caged nuts, used to assemble the unit in the cabinet.
Front mount assembly R77311 for MR-xxx TERRA
Different image parameters for day and night in Sunell cameras.
IP cameras Sunell have 4 schemes (working profiles) related to image settings. For each of them, all image parameters can be independently configured, including those related to exposure: mode and shutter speed, noise reduction, IR illuminator operation (on and power), HLC and BLC function operation, white balance, and color and focus compensation. The schemes can be switched depending on the status of the twilight sensor (then scheme 1 is valid for daytime, scheme 2 for nighttime) or according to the schedule hours. You can also permanently activate any of the 4 profiles.
Configuration window of the sensor parameters – selection of switching according to the state of the twilight sensor
Switching patterns have considerable advantages when it comes to the possibility of better adjustment to the conditions of the system site. Parameter switching schemes can be created in many ways. For example: you can manually adjust the shutter speed for both day and night. What will this do? During the day, the camera can work with a fast shutter speed, because there is more light and objects in motion will not be blurred. At night, this speed can be reduced, as more light may be more important than the fact that some frames of the image will be blurred.