DIPOL Weekly Review – TV and SAT TV, CCTV, WLAN

Implant turning thoughts into letters.

Researchers at Stanford University's Neural Prosthetics Translational lab have created a working brain-computer interface that can turn brain signals into letters. It provides real-time electronic text communication capabilities. The device tracks the electrical activity of the brain when the patient in draws a letter their mind and, based on that activity, it can tell what letter it is. Electrodes implanted in the frontal lobe record brain activity responsible for planning and making moves. Information from the electrodes is transmitted to the computer that analyzes the shape of the "imaginary" signs and selects the appropriate symbol from a specific set. The shapes are interpreted with artificial intelligence algorithms which have to predict the intended movements of the fingers and hands and, based on these, the sign the patient is thinking of.

Researchers have tested the device on a patient who is paralyzed from the neck down after an accident. He retained the ability to speak, but looked for ways to be active in the world of electronic information. The tests show that the brain retains the ability to control the execution of precise movements, such as writing characters, long years after the body has lost this ability. They also found that complex character-writing movements (changing speeds and trajectories) can be more easily and quickly interpreted by artificial intelligence algorithms than simpler movements such as moving a cursor in a straight line. In tests, the man was able to "type" 90 characters per minute, and the algorithm could read the characters with nearly 94 percent accuracy.

Today's systems generate characters based on eye movements or, as in the case of ACAT (Assistive Context Aware Toolkit) developed by Intel for professor Stephen Hawking, based on facial movements. However, their development is limited by their speed – they can generate only a few words per minute. Invasive, but more effective, is the use of systems capable of analyzing brain signals. They are implemented in the form of a connection between probes implanted in the brain and a computer and constitute a kind of BCI (Brain-Computer Interface). What is pioneering in this approach is the idea of converting imagined letters into their digital equivalents. Competing solutions attempt to use virtual keyboard control or decoding of entire words. However, they are slower and less accurate.

Hikvision Disk Calculator – calculating the storage time of recordings on the hard drive of a DVR.

Using the Disk Calculator v4.0.0.3 from Hikvision, you can determine how long recordings from cameras will be stored on the DVR's hard drive depending on the selected capacity. You can also specify the capacity of the hard drive depending on the required storage time of the recordings.

The software is very user-friendly and intuitive. In the "Channel Number" field, enter the number of cameras connected to the DVR. In the "Device Type" field, select a camera (IPC). In the "Resolution" field choose the resolution of the cameras. The resolutions available are from QCIF (176 x 144) to 12 MP (4000 x 3000). In the "Frame Rate" field, specify the number of frames per second (1/16 - 50). In the "Encoding" field, choose the compression method to be used (the DVR and camera have to support the chosen method). The calculator allows you to calculate storage capacity using three compression methods: H.264, H.264+ and H.265.

The H.265 compression method is two times more efficient than H.264, preserving the same image quality. It has been taken into account in the application - the recommended bit rate is half that of H.264 and the same disk capacity allows for doubling the data retention time. With 8 cameras in the system, 4 TB disk space, and 24/24 recording, the time periods will be 11 and 22 days, respectively.

TRISET PLUS – A+ class cable.

Cabling is one of the key parts of any TV system. To be transmitted successfully, the signal needs to be isolated from interfering signals generated by power lines or parallel TV and SAT cables (crosstalk). Quality coaxial cable should ensure low insertion loss and high screening efficiency. This feature is tested in the 30-3000 MHz range and typically takes values from 45 to more than 120 dB. For high screening efficiency in SMATV systems, we recommend using the TRISET PLUS E1016 cable.

TRISET PLUS E1016 complies with the A+ class requirements in the entire 30-3000 MHz frequency range. It also meets to a large extent the requirements for A++ class cables. The TRISET PLUS E1016 cable is recommended for use in systems with multiple antenna cables placed in parallel over a long distance or when power cables are located nearby.

What is the difference between the AGM and gel batteries?

Maintenance-free batteries are recommended for low-voltage systems. They are built to be completely leak-tight and do pose no risk of leakage of hazardous substances, so they can be used in any position. The batteries available are the AGM (Absorbed Glass Mat) or gel type.

In the AGM (Absorbed Glass Mat) batteries, the entire electrolyte is trapped (absorbed) in high porosity glass fiber separators between the lead plates. They have low internal resistance which means a higher voltage at the terminals and longer working time, particularly while being discharged with a high current drawn. This makes them best suited for buffer operation, i.e. they are used in UPS equipment.
The gel batteries in turn, have the electrolyte in a form of gel. They are resistant to deep discharge and are used as a power source for mobile devices such as forklifts or wheelchairs and with photovoltaic systems.

Twisted-pair cable on a suspension cable.

The NETSET F/UTP 5e E1519 is the finest-quality shielded cat. 5e twisted pair cable, designed for use in professional computer networks outside buildings. The shielding layer made of aluminum foil minimizes crosstalk and interference with the external environment. The outer sheath is made of polyethylene (PE) resistant to UV radiation and humidity. The cable is used for outdoor installation.

Key features of the NETSET BOX F/UTP 5e twisted pair cable:

• cable sheath made of PE polyethylene in black, outer diameter 6.4 mm,
• suspension cable diameter 1.2 mm,
• finest quality materials, perfect workmanship with a 15-year quality guarantee,
• parameters far exceeding the requirements of category 5e,
• pre-production quality control of raw materials and post-production quality control of the finished product,
• single-wire copper conductors with a diameter 0.5 mm (24 acc. to AWG),
• conductor insulation made of homogeneous, insulating PE dyed polyethylene, conductor diameter: 1 mm, insulation colors: white-green/green, white-orange/orange, white-brown/brown, white-blue/blue,
• polyester film,
• aluminum shield.

Optical attenuators – where and how to use.

Optical attenuators are passive elements of the optical path designed to reduce signal level and adjust it to the receiver sensitivity level. Systems with multimode optical fibers do not use attenuators for practical reasons – they do not have high power transmitters and use of attenuators is not necessary. They are usually used for short sections based on single-mode fibers.

To establish whether it is necessary to use an attenuator in a specific case, the optical power budget has to be checked. The transmitter power and receiver sensitivity, as well as the attenuation of the optical path between them are required. In theory, before proceeding with the installation, we can determine the expected attenuation values. The principles and sample calculations are shown in the Fiber optic line power balance library. However, the actual attenuation of the optical path can be measured only after placing the cables in a real system, using a stable light source and professional optical power meter.

Attenuators should always be installed at the receivers' inputs. The first reason is convenience - it is better to measure the actual signal level at the input of the receiver and adjust the attenuation to the desired level. The second reason is the fact that each attenuator reflects some part of the incoming signal. This part will be additionally attenuated by the link, before returning to the transmitter.

Redirecting calls from the Villa Hikvision IP door/gate station directly to a smartphone. 1-subscriber Villa Hikvision IP video gate/door stations have the ability to be added directly to the Hikvision cloud and to redirect calls to a smartphone with the Hik-Connect application installed without the need for an additional internal monitor (otherwise a monitor is always required). To use this functionality, connect the gate/door station to the Internet via wired or Wi-Fi link, create an account at www.hik-connect.com, install the Hik-Connect application and add the device to the account. Once the system is configured, pressing the call button on the door station will set up a connection on the smartphone with the app installed. After answering the call, it will be possible to have a two-way conversation and open the electric door strike or the gate...>>>more