Development of PAN (personal area network) for Mobile Robot Using Bluetooth Transceiver

In recent years, wireless applications using radio frequency (RF) have been rapidly evolving in personal computing and communications devices. Bluetooth technology was created to replace the cables used on mobile devices. Bluetooth is an open specification and encompasses a simple low-cost, low power solution for integration into devices. This research work aim was to provide a PAN (personal area network) for computer based mobile robot that supports real-time control of four mobile robots from a host mobile robot. With ad hoc topology, mobile robots may request and establish a connection when it is within the range or terminated the connection when it leaves the area. A system that contains both hardware and software is designed to enable the robots to participate in multi-agent robotics system (MARS). Computer based mobile robot provide operating system that enabled development of wireless connection via IP address

Net Worth Accumulation by Different Quintiles of Older Adults Approaching Retirement Age and 10 Years Later

The shift in responsibility for income security from the government to individuals makes the accumulation of net worth a vital issue. We investigated the rate of net worth accumulation for people aged 51 to 61 in 1991 (N=7,544) and 61 to 71 in 2001 (N=5,711) using the RAND Health and Retirement Study. We found that the rate of net worth accumulation by the fifth (top) quintile was extremely high in 1991, and the distribution of net worth became more skewed in favor of the wealthy in 2001. Older adults in the first and second quintiles are unable to face the challenge of the shift in responsibility for income security from the government to individuals

Oil Pollution in the Coastal Waters off Port Dickson, Straits of Malacca

The petroleum hydrocarbon dist1ibution in the Port Dichson coastal waters was studied over a period of three years from 1986 to 1989. Generally, there was no significant difference (P > 0.05) of hydrocarbon levels in water among the sampling stations on each of the sampling dates. However a pronounced fluctuation was found at different samping dates. Similarly, a pronounced fluctuation of hydrocarbon content in the sediment with different sampling dates was also detected. The mean hydrocarbon level in the water ranged between 14.69ppb and 150.28 ppb, ESSO 'Tapis A crude oil equivalent (or between 0.77 ppb and 7.87 ppb, chrysene equivalent), while for the sediment it ranged between 21. 73 mg/kg and 74.50 mg/kgdry sediment, Esso Tapis A crude oil equivalent (or between 1.12 mg/hgand 3. 90 mg/kgdry sediment, chrysene equivalent). The oil pollution level in the PortDickson coastal waters was comparable or higher than that found in the Exclusive Economic Zone watels off Pahang and Sabah, but was lower than that detected in the Terengganu and Sanl1uak waters. The saUTce of hydrocarbon pollution in the POTt Dichsm~ coastal waters was probably from the open sea and the nearby harbour and oil refineries rather than from land TUn of

System and method for calibrating inter-star-tracker misalignments in a stellar inertial attitude determination system

A method and apparatus for determining star tracker misalignments is disclosed. The method comprises the steps of defining a defining a reference frame for the star tracker assembly according to a boresight of the primary star tracker and a boresight of a second star tracker wherein the boresight of the primary star tracker and a plane spanned by the boresight of the primary star tracker and the boresight of the second star tracker at least partially define a datum for the reference frame for the star tracker assembly; and determining the misalignment of the at least one star tracker as a rotation of the defined reference frame

Singlet fermionic dark matter

We propose a renormalizable model of a fermionic dark matter by introducing a gauge singlet Dirac fermion and a real singlet scalar. The bridges between the singlet sector and the standard model sector are only the singlet scalar interaction terms with the standard model Higgs field. The singlet fermion couples to the standard model particles through the mixing between the standard model Higgs and singlet scalar and is naturally a weakly interacting massive particle (WIMP). The measured relic abundance can be explained by the singlet fermionic dark matter as the WIMP within this model. Collider implication of the singlet fermionic dark matter is also discussed. Predicted is the elastic scattering cross section of the singlet fermion into target nuclei for a direct detection of the dark matter. Search of the direct detection of the dark matter provides severe constraints on the parameters of our model.Comment: 12 pages, 7 figure

Wave Propagation in Lossy and Superconducting Circular Waveguides

We present an accurate approach to compute the attenuation of waves, propagating in circular waveguides with lossy and superconducting walls. A set of transcendental equation is developed by matching the fields at the surface of the wall with the electrical properties of the wall material. The propagation constant kz is found by numerically solving for the root of the equation. The complex conductivity of the superconductor is obtained from the Mattis-Bardeen equations. We have compared the loss of TE11 mode computed using our technique with that using the perturbation and Stratton’s methods. The results from the three methods agree very well at a reasonable range of frequencies above the cutoff. The curves, however, deviate below cutoff and at millimeter wave frequencies. We attribute the discrepancies to the dispersive effect and the presence of the longitudinal fields in a lossy waveguide. At frequencies below the gap, the superconducting waveguide exhibits lossless transmission behavior. Above the gap frequency, Cooper-pair breaking becomes dominant and the loss increases significantly

Modificación del doble enlace olefínico en ácidos grasos insaturados y en derivados de aceites vegetales via epoxidación: Revisión

The highly strained ring in epoxides makes these compounds very versatile intermediates. Epoxidized vegetable oils are gaining a lot of attention as renewable and environmentally friendly feedstock with various industrial applications such as plasticizers, lubricant base oils, surfactants, etc. Numerous papers have been published on the development of the epoxidation methods and the number is still growing. This review reports the synthetic approaches and applications of epoxidized vegetable oils.La alta tensión del anillo en los epóxidos hace que estos compuestos intermediarios sean muy versátiles. Los aceites vegetales epoxidados están ganando mucha atención como materia prima renovable y respetuosa con el medio ambiente con diversas aplicaciones industriales, tales como plastificantes, aceites base para lubricantes, tensioactivos, etc. Por esta razón, se han publicado numerosos trabajos sobre el desarrollo de métodos de epoxidación y el número todavía es creciente. Esta revisión aporta información sobre enfoques sintéticos y aplicaciones de aceites vegetales epoxidados

Faddeev-Jackiw Analysis of Topological Mass Generating Action

We analyze the gauge symmetry of a topological mass generating action in four dimensions which contains both a vector and a second rank antisymmetric tensor fields. In the Abelian case, this system induces an effective mass for the vector gauge field via a topological coupling $B \wedge F$ in the presence of a kinetic term for the antisymmetric tensor field $B$, while maintaining a gauge symmetry. On the other hand, for the non-Abelian case the $B$ field does not have a gauge symmetry unless an auxiliary vector field is introduced to the system. We analyze this change of symmetry in the Faddeev-Jackiw formalism, and show how the auxiliary vector field enhances the symmetry. At the same time this enhanced gauge symmetry becomes reducible. We also show this phenomenon in this analysis.Comment: 20 pages, REVTe