Black hole radiation with high frequency dispersion

We consider one model of a black hole radiation, in which the equation of motion of a matter field is modified to cut off high frequency modes. The spectrum in the model has already been analytically derived in low frequency range, which has resulted in the Planckian distributin of the Hawking temperature. On the other hand, it has been numerically shown that its spectrum deviates from the thermal one in high frequency range. In this paper, we analytically derive the form of the deviation in the high frequency range. Our result can qualitatively explain the nature of the numerically calculated spectrum. The origin of the deviation is clarified by a simple discussion.Comment: 9 pages, 10 figures, submitted to Phys.Rev.

Supervisory Autonomous Control of Homogeneous Teams of Unmanned Ground Vehicles, with Application to the Multi-Autonomous Ground-Robotic International Challenge

There are many different proposed methods for Supervisory Control of semi-autonomous robots. There have also been numerous software simulations to determine how many robots can be successfully supervised by a single operator, a problem known as fan-out, but only a few studies have been conducted using actual robots. As evidenced by the MAGIC 2010 competition, there is increasing interest in amplifying human capacity by allowing one or a few operators to supervise a team of robotic agents. This interest provides motivation to perform a more in-depth evaluation of many autonomous/semiautonomous robots an operator can successfully supervise. The MAGIC competition allowed two human operators to supervise a team of robots in a complex search-and mapping operation. The MAGIC competition provided the best opportunity to date to study through practice the actual fan-out with multiple semi-autonomous robots. The current research provides a step forward in determining fan-out by offering an initial framework for testing multi-robot teams under supervisory control. One conclusion of this research is that the proposed framework is not complex or complete enough to provide conclusive data for determining fan-out. Initial testing using operators with limited training suggests that there is no obvious pattern to the operator interaction time with robots based on the number of robots and the complexity of the tasks. The initial hypothesis that, for a given task and robot there exists an optimal robot-to-operator efficiency ratio, could not be confirmed. Rather, the data suggests that the ability of the operator is a dominant factor in studies involving operators with limited training supervising small teams of robots. It is possible that, with more extensive training, operator times would become more closely related to the number of agents and the complexity of the tasks. The work described in this thesis proves an experimental framework and a preliminary data set for other researchers to critique and build upon. As the demand increases for agent-to-operator ratios greater than one, the need to expand upon research in this area will continue to grow

Two Black Hole Holography, Lensing and Intensity

We numerically verify the analysis of the "expanding horizon" theory of Susskind in relation to the 't Hooft holographic conjecture. By using a numerical simulation to work out the image formed by two black holes upon a screen very far away, it is seen that it is impossible for a horizon to hide behind another. We also compute the intensity distribution of such an arrangement.Comment: 10 page

The Holographic Principle for General Backgrounds

We aim to establish the holographic principle as a universal law, rather than a property only of static systems and special space-times. Our covariant formalism yields an upper bound on entropy which applies to both open and closed surfaces, independently of shape or location. It reduces to the Bekenstein bound whenever the latter is expected to hold, but complements it with novel bounds when gravity dominates. In particular, it remains valid in closed FRW cosmologies and in the interior of black holes. We give an explicit construction for obtaining holographic screens in arbitrary space-times (which need not have a boundary). This may aid the search for non-perturbative definitions of quantum gravity in space-times other than AdS.Comment: 15 pages, 4 figures. Based on a talk given at Strings '99. Includes a reply to recent criticism. For more details, examples, and references, see hep-th/9905177 and hep-th/990602

Non supersymmetric strong coupling background from the large N quantum mechanics of two matrices coupled via a Yang-Mills interaction

We derive the planar large N non-supersymmetric background of the quantum mechanical hamiltonian of two hermitean matrices coupled via a Yang-Mills interaction, in terms of the density of eigenvalues of one of the matrices. This background satisfies an implicit non linear integral equation, with a perturbative small coupling expansion and a solvable large coupling solution, which is obtained. The energy of system and the expectation value of several correlators are obtained in this strong coupling limit. They are free of infrared divergences.Comment: Latex, 13 page

Omega 3, 6, 9 Enhanced Goat Meat (Omega-Chevon) from Flaxseed and Canola Fed Meat Goats

With growing obesity and cardiovascular disease concerns, the meat industry aims to reduce fat content in meat products. Currently Omega Fatty Acid (FA) enhanced beef and eggs are being marketed in the US, but Omega enhanced goat meat (Omega-Chevon) has not been developed. Meat goats were fed ground flaxseed and canola supplemented feed for 90 days. There were no palatability, weight, or health issues in meat goats fed canola and flaxseed supplemented feed. Chevon from goats fed canola and flaxseed had significant (

Computing the spectrum of black hole radiation in the presence of high frequency dispersion: an analytical approach

We present a method for computing the spectrum of black hole radiation of a scalar field satisfying a wave equation with high frequency dispersion. The method involves a combination of Laplace transform and WKB techniques for finding approximate solutions to ordinary differential equations. The modified wave equation is obtained by adding a higher order derivative term suppressed by powers of a fundamental momentum scale $k_0$ to the ordinary wave equation. Depending on the sign of this new term, high frequency modes propagate either superluminally or subluminally. We show that the resulting spectrum of created particles is thermal at the Hawking temperature, and further that the out-state is a thermal state at the Hawking temperature, to leading order in $k_0$, for either modification.Comment: 26 pages, plain latex, 6 figures included using psfi

The predictive influence of variables in three different academic learning environments on the intentions of music education majors to leave the degree program.

Attrition rates among students in music teacher training programs have contributed to a shortage of qualified music teachers for the nation's schools. The purpose of this study was to investigate the predictive relationship of academic variables in three different learning environments and the intent of a select population of music education majors to leave the degree program. The study drew upon the work of Tinto, Bean and Astin to form a theoretical foundation for examining variables unique to student withdrawal from the music education degree plan. Variables were examined within the context of three different learning environments: (1) applied lessons, (2) ensembles and (3) non-performance courses. Participants were 95 freshmen and sophomore music education majors at a public university who were enrolled in the music education degree program during the spring semester, 2002. Data included participant responses on the Music Student Inventory (MSI), a questionnaire developed specifically for the study, and grade data from university records. Independent variables in the study included participants' perceptions of (1) Ensemble experiences, (2) Applied lesson experiences, (3) Non-performance music course experiences, (3) Course requirements, and (4) Performance growth. Additional variables included: (1) Ensemble placement, (2) Course grades for music theory, applied lessons and aural skills, and (3) cumulative grade point averages. Gender interactions were also examined. The dependent variable in the study was intent to withdraw from the music education program. Data were analyzed using a binary logistic regression procedure. Results of the analysis indicated that none of the variables tested were statistically significant predictors of subjects' intentions to withdraw from the music education degree program. Gender interactions were not evident among the variables. Although statistically insignificant, the strongest predictor of the variables represented by questionnaire responses was lesson experiences. The ana ysis of course grades for music theory, applied lessons and aural skills failed to produce a statistically significant main effect, but applied lesson grades produced the strongest effect in the model. Results of the study suggest that students' intentions to withdraw from the music education program are related to variables other than those representing the academic component of the music education program

Developing a minimum dataset for nursing team leader handover in the intensive care unit: A focus group study

Background Despite increasing demand for structured processes to guide clinical handover, nursing handover tools are limited in the intensive care unit. Objectives The study aim was to identify key items to include in a minimum dataset for intensive care nursing team leader shift-to-shift handover. Methods This focus group study was conducted in a 21-bed medical/surgical intensive care unit in Australia. Senior registered nurses involved in team leader handovers were recruited. Focus groups were conducted using a nominal group technique to generate and prioritise minimum dataset items. Nurses were presented with content from previous team leader handovers and asked to select which content items to include in a minimum dataset. Participant responses were summarised as frequencies and percentages. Results Seventeen senior nurses participated in three focus groups. Participants agreed that ISBAR (Identify-Situation-Background-Assessment-Recommendations) was a useful tool to guide clinical handover. Items recommended to be included in the minimum dataset (≥65% agreement) included Identify (Name, age, days in intensive care), Situation (Diagnosis, surgical procedure), Background (Significant event(s), management of significant event(s)) and Recommendations (Patient plan for next shift,tasks to follow up for next shift). Overall, 30 of the 67 (45%) items in the Assessment category were considered important to include in the minimum dataset and focused on relevant observations and treatment within each body system. Other non-ISBAR items considered important to include related to the ICU (Admissions to ICU, staffing/skill mix, theatre cases) and patients (Infectious status, site of infection, end of life plan). Items were further categorised into those to include in all handovers and those to discuss only when relevant to the patient. Conclusions The findings suggest a minimum dataset for intensive care nursing team leader shift-to-shift handover should contain items within ISBAR along with unit and patient specific information to maintain continuity of care and patient safety across shift changes