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No. 21/2014 (May 26, 2014)
Solar panels instead of asphalt.
The replacement of traditional coal-fired power plants by renewable energy sources is the dream of many engineers. Scott Brusaw - an American electrical engineer, and his wife Julie, have been nearly a decade trying to make this dream reality. They want to implement the concept of photovoltaic panels covering roads, parking lots and sidewalks in order to use them for transformation of solar energy into electricity.Over eight years, their efforts have been many times recognized and awarded - World Technology Award, Ace Awards, IEEE - as well as honored by Google and NASA. In addition, two times they received contracts from the U.S. Federal Highway Administration to build prototypes.
The system has been called Solar Roadways and is based on tempered and textured glass panels in the shape of hexagons. Of course, the panels have been tested for impact and load resistance. They include built-in photovoltaic cells responsible for the conversion of energy.
A video showing the work on prototypes of the road panels
The cell panels are to be installed in parking lots and roads so that to cover as much of the surface as possible and maximize the amount of the generated electrical energy. Of course, the places should not be crowded, to keep the efficiency at a relatively high level. Such panels can also be installed on private estates, driveways, etc. Such "photovoltaic farms" can be directly connected to homes, business or public buildings and may provide the electricity needed by their users. The advantage of this design is the fact that the panels do not change the landscape - they do not occupy the roofs or facades of buildings, do not take specially allotted areas of land.
Test installation on a small part of a parking lot, in which 69% of the glass panels have been equipped with solar cells, generates on average 3600 W of electric power. The strength of the panels has been tested with the use of 125 ton-weighing vehicles.
The energy can also be used for signalling (with built-in LEDs) and preventing snow/ice accumulation (with built-in heating elements) on the road surface - an interesting way to "intelligent" roads... The originators are currently looking for a wider range of funds to support their efforts - to build and test larger installations and to refine the technology.
Struggle with attenuation in optical networks.
The phenomenon of signal attenuation is the basic problem of the transmission of information over long distances. In the case of fiber-optic networks, an additional attenuation can be caused by factors such as inadequate precision of splices or too small bending radius. However, it happens that the attenuation of a link is too high, despite observing the basic rules. |  | |
A dirty ferrule end face (on the left) and the face cleaned with the NC-001 tool.
Improper cleaning of ferrule end faces may cause permanent scratches.
The sometimes forgotten or ignored factor increasing attenuation is a dirty ferrule end face. It may be the main and only reason for the trouble with the transmission of optical signal.
A good and cheap solution to this problem is to clean all terminations during the installation process. The ferrule end-face cleaner NC-001 removes dust, dirt and contaminants prior to mating a fiber optic connection. The special structure of the fabric accurately collects pollution, at the same time avoiding any scratching. Solid casing gives a good grip of the tool during operation. Interchangeable microfiber replacement reels L5917 ensure long life of the tool. The casing protects the cleaning surface against pollution during transport.
Additional DVB-T transmitters may cause reception problems.
In many places where signals from the main DVB-T transmitter(s) are insufficient and do not guarantee a satisfactory reception quality, it is necessary to use gap filler transmitters, repeating all or selected digital multiplexes. The consequence of the additional signal sources may be a significant difference between the levels of the received multiplexes. When the receiving antenna system features too high gain (especially having preamplifiers or amplifiers), the problems with overdriving active elements in the antenna system or in the receivers may cause severe reception problems.Another significant problem in Single Frequency Networks (SFN) in which the signals from neighboring transmitters are broadcast at the same frequency (channel) is called the "effect of 0 dB". This phenomenon is particularly noticeable in the case of receivers with less advanced reception systems, when they have at their inputs two or more signals with comparable (and very good) levels and with very small time delay(s). The problem with the reception may arise here from the lack of technical capabilities to synchronize the receiver with the two very similar, however different signals. This phenomenon is most likely to occur where:
- the receiving DVB-T antenna is in line with the high-power and gap-filler transmitters
- the receiving DVB-T antenna with a wide reception angle receives signals from the high-power and gap-filler transmitters
The solutions to the problems will be presented in the next issue of the Newsletter.
How to quickly configure multiple DVRs?
Several DVRs installed in the same facility should usually have the same or similar settings. In the case of Ultimax DVRs, it is possible to export a configuration file with settings from one device to other DVRs. The export/import of settings can be performed in two ways:- by connecting hard drive to USB port of DVRs
- via the network, with the use of VMS software or a web browser - the method is preferred when the physical locations of the DVRs are more distant
Monitoring profiles in IP CCTV systems.
IP CCTV systems have the advantage that the camera images can be viewed both locally and remotely via smartphones and computers with Internet access. The limitation of the video data transmission is the capacity of the links, especially of the uplinks uploading the streams from the cameras to the network. Similarly, inadequate connection from the client side also may block proper transmission of the images, manifested by slowness, frozen images etc.To prevent such problems, the administrators should create at least two monitoring profiles:
- recording and full-screen monitoring - setting the highest possible parameters of the equipment used (frame rate, resolution and image quality) to get the maximum amount of detail - the bandwidth is about 5 Mbps
- remote monitoring and local viewing in screen division mode - medium image quality for viewing all cameras simultaneously, with trouble-free access via the Internet - the satisfactory bandwidth is 0.7-1 Mbps)
The new window presents the list of compatible accessories:
The user gets a list of accessories compatible with the selected RACK cabinet, can look up their descriptions, add any of them to the Cart or Favorites.
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 | Switch Mode Power Supply PSDC161212T M18297 is used to power devices requiring 12 VDC or similar stabilized voltage (within 12...15 VDC range). Its modern switch-mode converter shows 83% efficiency and provides stable low-noise DC voltage. The 16 outputs (each with 0.8 A current capacity) are protected with individual fuses. | |
The latest
 | Programmable Signal GSM amplifier with remote monitoring of operating parameters. Through the GSM system the administrator can switch on and off the device, select the operating band, set the optimum gain. In addition, the amplifier can send information on the actual parameters. The device can cover an area up to 2000m2. >> more |
 | Trans-Data BTS antennas are intended for use at base stations. The antennas from the series launched by DIPOL can be fed with signals with power up to 400 W and tilted with RCU. >> more |
On May 27, Mr. Lukasz Kopciuch, engineer from DIPOL, will deliver the lecture How to improve GSM signal in difficult environments at the Mobile Trends for Business conference (10:35 CET), and another lecture Strengthening cellular signals inside buildings with the use of GSM repeaters at the Mobile-IT trade fair (16:00 CET). The lectures will be given in Polish.
Worth reading
TP-LINK wireless router as a DLNA server. Many televisions available on the market are equipped with LAN ports that can be connected to Ethernet networks to cooperate with other DLNA certified devices. DLNA stands for the Digital Living Network Alliance, a non-profit collaborative trade organization gathering hundreds of member companies operating in the fields of consumer electronics, computer equipment, mobile devices. The home network devices compatible with DLNA include PCs and network attached storage (NAS) devices, TVs, stereos, home theaters, audio/video receivers, video displays, game consoles, tablets, PDAs, network printers, smartphones etc. Depending on the software installed, any of the devices can provide remote access to multimedia content... more
