4,074 research outputs found

    The spatially homogeneous relativistic Boltzmann equation with a hard potential

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    In this paper, we study spatially homogeneous solutions of the Boltzmann equation in special relativity and in Robertson-Walker spacetimes. We obtain an analogue of the Povzner inequality in the relativistic case and use it to prove global existence theorems. We show that global solutions exist for a certain class of collision cross sections of the hard potential type in Minkowski space and in spatially flat Robertson-Walker spacetimes.Comment: 21 page

    Motion-Driven Transparency and Opacity.

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    When two adjacent surfaces move in step, this can generate a sensation of transparency, even in the absence of intersections. Stopping the motion of one surface makes it look suddenly opaque

    Multi-bot Easy Control Hierarchy

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    The goal of our project is to create a software architecture that makes it possible to easily control a multi-robot system, as well as seamlessly change control modes during operation. The different control schemes first include the ability to implement on-board and off-board controllers. Second, the commands can specify either actuator level, vehicle level, or fleet level behavior. Finally, motion can be specified by giving a waypoint and time constraint, a velocity and heading, or a throttle and angle. Our code is abstracted so that any type of robot - ranging from ones that use a differential drive set up, to three-wheeled holonomic platforms, to quadcopters - can be added to the system by simply writing drivers that interface with the hardware used and by implementing math packages that do the required calculations. Our team has successfully demonstrated piloting a single robots while switching between waypoint navigation and a joystick controller. In addition, we have demonstrated the synchronized control of two robots using joystick control. Future work includes implementing a more robust cluster control, including off-board functionality, and incorporating our architecture into different types of robots

    Utility Maximisation: Non-concave utility and non linear expectation

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    Since the birth of mathematical nance, portfolio selection has been one of the topics which have attracted a lot of interest, with models formulated in discrete and continuous time and developed in complete and incomplete markets. In conventional or neoclassical finance, many models are based off the assumption that agents make decisions by maximising their expected utility. Deviations between models and market observations have generated a recent field of study, behavioural finance, which incorporates psychology, sociology and finance together to resolve observed phenomenon like bubbles which conventional finance cannot explain. In this thesis, we will be restricting ourselves to the complete continuous market and look at a new formulation of expected utility maximisation with behavioural finance elements incorporated into it, namely S-shaped utilities and probability distortions. We consider the three general cases of expected utility maximisation: utility from terminal wealth, utility from consumption and utility from terminal wealth and consumption. We shall review the neoclassical problems and then explore the cases with behavioural elements installed. \ud \ud Key Words: Portfolio Selection, continuous time, martingale approach, Sshaped function, probability distortion, cumulative prospect theor

    Clinical management of behavioral characteristics of Prader–Willi syndrome

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    Prader–Willi syndrome (PWS) is a complex neurodevelopmental disorder caused by an abnormality on the long arm of chromosome 15 (q11–q13) that results in a host of phenotypic characteristics, dominated primarily by hyperphagia and insatiable appetite. Characteristic behavioral disturbances in PWS include excessive interest in food, skin picking, difficulty with a change in routine, temper tantrums, obsessive and compulsive behaviors, and mood fluctuations. Individuals with PWS typically have intellectual disabilities (borderline to mild/moderate mental retardation) and exhibit a higher overall behavior disturbance compared to individuals with similar intellectual disability. Due to its multisystem disorder, family members, caregivers, physicians, dieticians, and speech-language pathologists all play an important role in the management and treatment of symptoms in an individual with PWS. This article reviews current research on behavior and cognition in PWS and discusses management guidelines for this disorder

    Determinants and Impacts of the Relative Use of Depository Receipts and Euro Convertible Bonds by High-tech Corporations: An Empirical Study

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    This paper adopts Taiwan's high-tech companies as the sample to address and examine four new determinants of various foreign financing instruments and test their impacts on the issuing firms. Our empirical findings are consistent with the following notions. First, the firms with higher foreign holding and foreign investment will be likely to adopt foreign financing policy. Moreover, the firms with higher stock dividend payment in Taiwan will adopt both of ECB (Euro convertible bond) and DR (depository receipt). Firm managers with better education background will prefer DR. Second, the use of DR can effectively decrease the volatility of stock returns but also pronounce a negative influence on the mean of stock returns. In contrast, the use of ECB can effectively increase the mean but can not significantly decrease the volatility.

    Destructive Hostility: The Jeffrey Dahmer Case: A Psychiatric and Forensic Study of a Serial Killer

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    We were involved as forensic experts in the case of the serial killer Jeffrey Dahmer. We discuss the scene and victim autopsy findings, with a brief consideration of the basic emotion of hostility. These findings support the thesis that at the basis of this serial killer\u27s behavior were primary unconscious feelings of hate that he had channeled into a sadistic programmed destruction of 17 young men. The interview of the serial killer, the photographic scene documentation, and the autopsy findings stress the ambivalent homosexuality of the killer, his sexual sadism, his obsessive fetishism, and his possible cannibalism and necrophilia

    Case report: Epigastric Abdominal Pain from Beverage Ingestion of Freshly Squeezed Juice of the Hardy Orange Flying Dragon Plant (Poncirus trifoliata)

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    We report the case of a 25 year old male who presented to the ED with epigastric abdominal pain after ingesting a freshly squeezed beverage form of Flying Dragon Hardy Orange plant (Poncirus trifoliata). Poison control was contacted and recommended symptomatic treatment only. The patient’s pain resolved while in the emergency department. Seed and rind preparations have been used as an herbal remedy in East Asia. Freshly squeezed Poncirus trifoliata can cause significant abdominal pain
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