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Review of Speculative "Disaster Scenarios" at RHIC  [PDF]
R. L. Jaffe,W. Busza,J. Sandweiss,F. Wilczek
Physics , 1999, DOI: 10.1103/RevModPhys.72.1125
Abstract: We discuss speculative disaster scenarios inspired by hypothetical new fundamental processes that might occur in high energy relativistic heavy ion collisions. We estimate the parameters relevant to black hole production; we find that they are absurdly small. We show that other accelerator and (especially) cosmic ray environments have already provided far more auspicious opportunities for transition to a new vacuum state, so that existing observations provide stringent bounds. We discuss in most detail the possibility of producing a dangerous strangelet. We argue that four separate requirements are necessary for this to occur: existence of large stable strangelets, metastability of intermediate size strangelets, negative charge for strangelets along the stability line, and production of intermediate size strangelets in the heavy ion environment. We discuss both theoretical and experimental reasons why each of these appears unlikely; in particular, we know of no plausible suggestion for why the third or especially the fourth might be true. Given minimal physical assumptions the continued existence of the Moon, in the form we know it, despite billions of years of cosmic ray exposure, provides powerful empirical evidence against the possibility of dangerous strangelet production.
Scenarios of disaster, visions of liberation  [cached]
Steven Best
Revista Theomai , 2004,
Abstract: As the planet spirals ever deeper into social and natural disaster, with all things becoming ever more tightly knit into the tentacles of global capitalism, there is an urgent need for new maps and compasses to help steer us into a viable mode of existence. Karl Marx′s 1843 call for a ruthless criticism of everything existing has never been more urgent and appropriate, but all too often today critique is merely academic, stratospheres away from concrete action and progressive social policies. Yet, social critique and change in the slaughterhouse of capitalism needs to be guided and informed by powerful descriptions of what is -- the degraded forfeiture of human potential in a world where over a billion people struggle for mere existence -- but also by bold new visions of what can be, imaginative projections of how human beings might harmoniously relate to one another and the living/dying earth
Ontology-based collaborative framework for disaster recovery scenarios  [PDF]
Sakkaravarthi Ramanathan,Aymen Kamoun,Khalil Drira,Christophe Chassot
Computer Science , 2012,
Abstract: This paper aims at designing of adaptive framework for supporting collaborative work of different actors in public safety and disaster recovery missions. In such scenarios, firemen and robots interact to each other to reach a common goal; firemen team is equipped with smart devices and robots team is supplied with communication technologies, and should carry on specific tasks. Here, reliable connection is mandatory to ensure the interaction between actors. But wireless access network and communication resources are vulnerable in the event of a sudden unexpected change in the environment. Also, the continuous change in the mission requirements such as inclusion/exclusion of new actor, changing the actor's priority and the limitations of smart devices need to be monitored. To perform dynamically in such case, the presented framework is based on a generic multi-level modeling approach that ensures adaptation handled by semantic modeling. Automated self-configuration is driven by rule-based reconfiguration policies through ontology.
Other Exotic Scenarios at the LHC  [PDF]
Kamal Benslama,for the ATLAS,CMS Collaborations
Physics , 2007,
Abstract: The considerable center-of-mass energy and luminosity provided by the Large Hadron Collider (LHC) will ensure a discovery reach for new particles which extends well into the multi-TeV region. ATLAS and CMS have carried out many studies of the implications of this capability for Beyond the Standard Model physics. In this paper, we summarize some key results of studies involving non-susy models, such as extra-dimensions, little higgs, compositeness, and left-right symmetric models.
Cognitive Scout Node for Communication in Disaster Scenarios  [PDF]
Rajesh K. Sharma,Anastasia Lavrenko,Dirk Kolb,Reiner S. Thom?
Journal of Computer Networks and Communications , 2012, DOI: 10.1155/2012/160327
Abstract: The cognitive radio (CR) concept has appeared as a promising technology to cope with the spectrum scarcity caused by increased spectrum demand due to the emergence of new applications. CR can be an appropriate mean to establish self-organization and situation awareness at the radio interface, which is highly desired to manage unexpected situations that may happen in a disaster scenario. The scout node proposed in this paper is an extended concept based on a powerful CR node in a heterogeneous nodes environment which takes a leading role for highly flexible, fast, and robust establishment of cooperative wireless links in a disaster situation. This node should have two components: one is a passive sensor unit that collects and stores the technical knowledge about the electromagnetic environment in a data processing unit so-called “radio environment map” in the form of a dynamically updated database, and other is an active transceiver unit which can automatically be configured either as a secondary node for opportunistic communication or as a cooperative base station or access point for primary network in emergency communications. Scout solution can be viable by taking advantage of the technologies used by existing radio surveillance systems in the context of CR. 1. Introduction Communication has been an indispensable part of everyday life in the present days. Apart from making the general life better, modern communications should also be applicable for relief and support to the victims of exceptional adverse situations which include disaster scenarios like earthquakes, floods, cyclones, forest fires and terrorist attacks. Such scenarios impose new requirements on the communication systems. Some of the tasks of a cognitive radio network for emergency situations may be (1) to support specific service requests (higher traffic, coverage, localization, emergency messages, etc.), (2) to re-establish communications in a short time, and (3) to assist rescue forces communications and provide interoperability among them and also among rescue forces and public network. One of the first tasks in disaster is to organize rescue operations in a quick and efficient manner which as well requires rescue forces to be provided with reliable and stable communication facilities. One of the common problems here is providing interoperability among rescue responders originally using different communication standards [1, 2]. In terms of public communication systems, obvious problems in such scenarios are capacity overload with the resulting service denial and absence of coverage
Accelerator Disaster Scenarios, the Unabomber, and Scientific Risks  [PDF]
Joseph I. Kapusta
Physics , 2008, DOI: 10.1007/s00016-007-0366-y
Abstract: The possibility that experiments at high-energy accelerators could create new forms of matter that would ultimately destroy the Earth has been considered several times in the past quarter century. One consequence of the earliest of these disaster scenarios was that the authors of a 1993 article in "Physics Today" who reviewed the experiments that had been carried out at the Bevalac at Lawrence Berkeley Laboratory were placed on the FBI's Unabomber watch list. Later, concerns that experiments at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory might create mini black holes or nuggets of stable strange quark matter resulted in a flurry of articles in the popular press. I discuss this history, as well as Richard A. Posner's provocative analysis and recommendations on how to deal with such scientific risks. I conclude that better communication between scientists and nonscientists would serve to assuage unreasonable fears and focus attention on truly serious potential threats to humankind.
Managing Risk in Disaster Scenarios with Autonomous Robots
Daniel P. Stormont,Vicki H. Allan
Journal of Systemics, Cybernetics and Informatics , 2009,
Abstract: Disaster areas are one of the most challenging environments faced by mankind. Uncertainty, hazards, and limited availability of rescuers all impact the ability to save lives. Prepositioned autonomous rescue robots offer promise in assisting the rst responders to a disaster site, but there is a challenge to using robots in hazardous environments: numerous studies have shown that human rescuers lack trust in fully autonomous systems. This paper introduces the aspects of disaster areas that make them so challenging. The use of robots as a risk management tool for human rescuers is introduced. Then some of the factors that limit human trust in robots are addressed – including one of the key factors: reliability. The design of a computer model used to investigate issues of trust and the impact of reliability in a re ghting scenario is discussed and the results are analyzed. Finally, some preliminary conclusions and plans for further work in this area are presented.
Black Hole Entropy and Exclusion Statistics  [PDF]
Hyeong-Chan Kim,Yoonbai Kim,Phillial Oh
Physics , 1998,
Abstract: We compute the entropy of systems of quantum particles satisfying the fractional exclusion statistics in the space-time of 2+1 dimensional black hole by using the brick-wall method. We show that the entropy of each effective quantum field theory with a Planck scale ultraviolet cutoff obeys the area law, irrespective of the angular momentum of the black hole and the statistics interpolating between Bose-Einstein and Fermi-Dirac statistics.
Information Fusion-Based Storage and Retrieve Algorithms for WSNs in Disaster Scenarios
Zhe Xiao,Ming Huang,Jihong Shi,Wenwei Niu,Jingjing Yang
International Journal of Distributed Sensor Networks , 2012, DOI: 10.1155/2012/524543
Abstract: Sensor networks are especially useful in catastrophic or disaster scenarios such as abysmal sea, floods, fires, or earthquakes where human participation may be too dangerous. Storage technologies take a critical position for WSNs in such scenarios since the sensor nodes may themselves fail unpredictably, resulting in the loss of valuable data. This paper focuses on fountain code-based data storage and recovery solutions for WSNs in disaster scenarios. A review on current technologies is given on challenges posed by disaster environments. Two information fusion-based distributed storage (IFDS) algorithms are proposed in the “few global knowledge” and “zero-configuration” paradigm, respectively. Correspondingly, a high-efficient retrieve algorithm is designed for general storage algorithms using Robust Soliton distribution. We observe that the successful decoding probability can be provisioned by properly selecting parameters—the ratio of number of source node and total nodes, and the storage capacity M in each node.
Dark Matter Production at LHC from Black Hole Remnants  [PDF]
Gouranga C Nayak
Physics , 2009, DOI: 10.1134/S1547477111040121
Abstract: We study dark matter production at CERN LHC from black hole remnants (BHR). We find that the typical mass of these BHR at LHC is ~ 5-10 TeV which is heavier than other dark matter candidates such as: axion, axino, neutralino etc. We propose the detection of this dark matter via single jet production in the process pp -> jet +BHR(dark matter) at CERN LHC. We find that for zero impact parameter partonic collisions, the monojet cross section is not negligible in comparison to the standard model background and is much higher than the other dark matter scenarios studied so far. We also find that d\sigma/dp_T of jet production in this process increases as p_T increases, whereas in all other dark matter scenarios the d\sigma/dp_T decreases at CERN LHC. This may provide an useful signature for dark matter detection at LHC. However, we find that when the impact parameter dependent effect of inelasticity is included, the monojet cross section from the above process becomes much smaller than the standard model background and may not be detectable at LHC.
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