There are various solutions for powering communications nodes. The cheapest, with extremely low consumption, use primary cells (non-rechargeable batteries). For a longer life, applications are being developed that will use batteries based on various technologies (Pb-acid, NiMH, NiCd, Lithium cells, etc.). But all batteries have a limited number of charging-discharging cycles: a few thousand, at comfortable temperatures (between 15°C and 25°C) and incomplete discharge. The storage capacity decreases with each cycle, and is greatly accentuated in the case of over-discharge. In addition, the performance of standard batteries at low temperatures is low (limited capacity, low charging and discharging rate, increased internal resistance). In addition, the price limits the use of cells designed to operate at extreme temperatures (-40°C to + 80°C), in isolated locations that remain in hard-to-reach areas. New power systems are moving towards the use of supercapacitors (EDLC) which are becoming cheaper and cheaper with increasing energy density. They are very reliable passive devices, which exceed the battery life, the number of cycles and the robustness of any battery on the market today, without feeling the effects of low temperatures. The number of cycles reaches hundreds of thousands, and at the end of them to a doubled internal resistance (which remains in the range of millions) and to a slight reduction in capacity (10% -20%). Since a good capacitor has a lifespan of about 20 years, a carefully designed communications node outperforms any network with nodes powered by standard batteries. Under these conditions, hybrid power solutions are required, which, in addition to a small capacity battery, power supply, includes supercapacitors to improve the performance of the power system.
Interest towards automotive domain has increased in the last few years. Few key factors that led to this are: economic conditions, clients' interest, their preferences and demands, globalization and innovation in technology. Recently, brushless DC motors, are increasingly sought after because of their advantages and can replace brushed motors. The wide range of applications where brushless DC motors can be used provide added confidence in their use for automotive applications to replace old systems.
In this paper a demo application of windscreen wipers using brushless DC motors will be presented. Noise reduction, space saving and more detailed control of wipers could be possible by controlling windscreen wipers independently with Brushless DC motors (BLDC).
An intelligent network represents a generic concept of implementing some telecommunication networks with configurations that are independent of the quality service type offered to the user. Likewise, this concept defines the possibility to offer new services, without extensively intervening into the architecture of the support network.
This paper will focus on concepts, architectures, as well as identification and evaluation methods of risks and threats represented by the threats posed to security and quality of the intelligent networks, like they were defined by the international organization for standardization. There will be analyzed an environment consisting of a set of interconnected intelligent networks (networks operated by different providers of service/ different network operators, having their own security policies and quality insurance, and independent form one another) and an analysis will be performed (definition of the threats, evaluation of the impact, methods of putting into practice, definition of the possible countermeasures) of the threats which address these interconnected environments.
Relying on the list of possible threats, after doing research, there will be proposed a method of analysis and evaluation of the security risks emerged into the system along with the existence of these threats. The following services are considered the best option of advanced services implementation within the intelligent networks: possible threats, risks, security mechanisms.
These days many variants for lighting systems are available on the market, and new solutions are about to emerge. Most of the new lamps are offered in form to be retrofitted to existing sockets and luminaires. In this paper, are presented some systematically investigations on different lamps as LEDs, Compact Fluorescent Lamps (CFLs), tungsten, and new available Cold Cathode Fluorescent Lamps (CCFLs), regarding the light level, dimming performances and also the resulting flicker and power distortion performances. The light level was expressed by the illuminance level, measured for all lamps in the same conditions, at the same distance and on the same surface represented by the photometer probe.
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