Contactlesss Eddy Current Braking System in Automobiles

In mechanical type braking system which are being used now days to stop or retard the automobile by means of artificial frictional resistance. This causes skidding and wear & tear of the vehicle which may cause serious problems. If the speed of the vehicle is very high, then it will not provide high braking torque, which may cause less frictional resistance during braking action and it will cause problems like accidents. These drawbacks of mechanical type brakes can be overcome by a simple, effective and efficient mechanism of braking system which is called as �The Non contactless braking system or Eddy current braking System�. It is a non contact type braking system then it is an abrasion-free method for braking in automobiles. It makes use of the opposing tendency of Eddy current. Eddy current are the loops of or swirling electric current produced in a conductor,by changing the magnetic field .The change of magnetic field is required for generating flux by the principle of faraday law. In eddy currents braking energy such as kinetic energy transform into heat, which is an unused energy. In some applications, the useful energy is lost i.e not particularly desirable. But there are some practical applications such an application is the eddy current brake.[1]This paper report explores the working principle of eddy current brake mechanism. In eddy current braking, like a conventional friction brake, which is responsible for slowing an object, such as a train or a roller coaster etc. In the friction braking, the pressure is applied on two separate objects, but in eddy current braking an object is stopped by creating eddy currents through electromagnetic induction which creates resistance, and in turn either heat or electricity. For such a breaker, we give analytical formulas considering end effects for its magnetic field, eddy current distribution, forces according to the secondary relative permeability, and conductivity. The results given here are purely analytic.[2]The principle of braking in road vehicles involved the conversion of kinetic energy into heat. This heat energy conversion therefore demands and appropriate rate of heat dissipation if a reasonable temperature and performance stability are to be maintained. The electromagnetic brakes works in relatively cool condition thus it avoid problem that friction brake face by using a totally different working principle and installation location. By using electromagnetic braking as substitute retardation equipment, the friction braking may be used less as compared and therefore practically never reach high temperature. Thus by eddy current braking brakes have a longer life , and potential �brake fade� problem can be avoided, it is apparent that the electromagnetic brake is an essential compliment to the safe breaking of vehicles.[3

Assessment of Oral Hygiene Habits among the Dental Students of Bhopal, Madhya Pradesh: A Questionnaire Survey

The aim of conducting this study was to evaluate the oral hygiene attitudes among the budding dentists, and whether progressive dental education and their understanding of preventive dental procedures will improve their commitment toward enhancement of their own oral health attitudes. For this purpose, a cross sectional study was designed for 400 dental students of Bhopal divided into group A (first year and second year) and group B (third year and final year) using a custom formulated objective type of questionnaire to explore their dental health attitudes and behavior based on gender and level of dental education. The complex interplay of factors that shape attitudes and health behaviors, two major influences appear central: culturally determined attitudes/beliefs and behaviors (social norms), and learned experiences. Gender seems to play an important role as data collected show females belonging to both the groups to be having better self-reported health attitudes in majority of investigated areas. The findings of the present study highlighted the relatively poor oral health behavior of Indian dental students, which should be improved in order to serve as a positive model for their patients, family and friends

A Countdown to Orthognathic Surgery

For patients whose orthodontic problems are so severe that neither growth modification nor camouflage offers a solution, surgery to realign the jaws or reposition dentoalveolar segments is the only possible treatment. Surgery is not a substitute for orthodontics in these patients. Instead, it must be properly coordinated with orthodontics and other dental treatment to achieve good overall results