Disentanglement by Dissipative Open System Dynamics

This paper investigates disentanglement as a result of evolution according to a class of master equations which include dissipation and interparticle interactions. Generalizing an earlier result of Di\'{o}si, the time taken for complete disentanglement is calculated (i.e. for disentanglement from any other system). The dynamics of two harmonically coupled oscillators is solved in order to study the competing effects of environmental noise and interparticle coupling on disentanglement. An argument based on separability conditions for gaussian states is used to arrive at a set of conditions on the couplings sufficient for all initial states to disentangle for good after a finite time.Comment: Paper in conjunction with and following on from P.J. Dodd and J.J. Halliwell: quant-ph/031206

Evaluation of Modification of the Upper Batavia Dam on the Fox River, Illinois

Progress Report, Federal Aid Project F-136-R Segment 6Report issued on: August 2004Submitted to Office of Water Resources, Illinois Department of Natural Resource

Mössbauer Spectrometry Study of Thermally-Activated Electronic Processes in Li_xFePO_4

The solid solution phase of Li_xFePO_4 with different Li concentrations, x, was investigated by Mössbauer spectrometry at temperatures between 25 and 210 °C. The Mössbauer spectra show a temperature dependence of their isomer shifts (E_(IS)) and electric quadrupole splittings (E_Q), typical of thermally activated, electronic relaxation processes involving ^(57)Fe ions. The activation energies for the fluctuations of E_Q and E_(IS) for Fe^(3+) are nearly the same, 570 ± 9 meV, suggesting that both originate from charge hopping. For the Fe^(2+) components of the spectra, the fluctuations of E_Q occurred at lower temperatures than the fluctuations of E_(IS), with an activation energy of 512 ± 12 meV for E_Q and one of 551 ± 7 meV for E_(IS). The more facile fluctuations of E_Q for Fe^(2+) are evidence for local motions of neighboring Li^+ ions. It appears that the electron hopping frequency is lower than that of Li^+ ions. The activation energies of relaxation did not have a measurable dependence on the concentration of lithium, x

Influence of semicon shields on the dielectric loss of XLPE cables

Dielectric response measurement techniques in both time and frequency domains are studied in order to measure the dielectric loss of XLPE cables, which have very low losses. A high sensitivity transformer ratio bridge system, which can measure loss tangents as low as 10-5, has been developed with the ability to measure these cables. A tuned amplifier was designed to help to extend the frequency range from 200Hz to 20kHz. Different model cables from Borealis AB with different semiconducting materials have been measured in the temperature range 15⁰C to 120⁰C. It is found that the semiconducting layers dominate the dielectric loss in the insulation system of the XLPE cables, when the outer semicon is treated as measuring electrode. In this case, steadily increasing dielectric loss has been measured at higher frequencies. The resistivity of the semiconducting materials was measured, which confirmed that the increasing slope is due to the semiconducting layers. After using conductive tapes to wrap the cable samples, monotonically decreasing losses were measured, corresponding to the actual dielectric frequency response of the XLPE cables. It is concluded that the axial resistance of semiconducting shields have a substantial influence on the dielectric loss of XLPE cables, especially for dielectric response in high frequency range. A device on measuring the loss of such cables is presented

Design and Testing of an Automated SemiÂ]Trailer Control System

Growing up in Maine, the trucking industry is an ever-present part of life. With a very sparse, lightly used rail system, almost all of the raw materials and goods that enter and leave the state do so by truck. Truckers in Maine are constantly challenged by Maine’s roads, which can often be difficult or even treacherous to navigate. The rough logging roads near Jackman or Millinocket, or the sharp ninety degree turns near the Portland oil docks, can ruin a trucker’s day, or even worse, cause an accident. For example, there is a tiny four-way intersection on Broadway in South Portland, where full-length oil semi-trucks have to turn ninety degrees as they leave the massive oil storage tanks at the docks. Broadway is a very busy road; as soon as the trucks get the signal to turn, there are lines of cars stopped at the light. The trucks have to turn wide, right into the stopped line of cars. This means the cars then have to coordinate and back up to allow the truck to turn. After much confusion and after the light has turned green, then red, then green again about ten times with the trailer completely cutting off the intersection, the truck can move on. The same thing happens along the backroads of Millinocket. When trucks come off the logging roads they usually have to turn ninety degrees onto the main road. This is tricky to do at best, and dangerous at worst. The roads usually aren’t wide enough for the truck to turn onto them without going over the other side. If the logging companies don’t build pulloffs on the side of the road for the trucks to run through, then eventually a trucker is going to try to turn on to the main road and end up in the ditch on the other side, with the trailer completely blocking the way until the truck can be moved

A simple operational interpretation of the fidelity

This note presents a corollary to Uhlmann's theorem which provides a simple operational interpretation for the fidelity of mixed states.Comment: 1 pag

Technology utilization in a non-urban region: Further impact and technique of the Technology Use Studies Center, 2

The clientele served by the Technology Use Studies Center (TUSC) is updated. Manufacturing leads the list of client firms. The standard industrial classification (SIC) range of these firms is broad. Substantial numbers of college and university faculties are using TUSC services. Field operations inherent in the functions of dissemination and assistance are reviewed. Increasing emphasis among clientele is on environmental concerns and management. A record is provided of the institutions contacted and the extent of TUSC involvement with them, as well as TUSC's cooperation with agencies and organizations. The impact of TUSC and the NASA-sponsored Technology Utilization Program on other public agencies is discussed

Technology utilization

Documentation is presented for selected transfer and impact reports provided to the business community, government agencies, and such other requestors as schools, universities, and health services. Statistical data are also included on the characteristics of the TUSC technical searches