bluuebunny/crossref_metadata_2025 huggingface dataset:
FAST LEARNING ALGORITHM OF WAVELET NETWORK BASED ON FAST WAVELET TRANSFORM
Authors: JEMAI OLFA , ZAIED MOURAD , AMAR CHOKRI BEN , ALIMI MOHAMED ADEL
Published: January 2012

In this paper, a novel learning algorithm of wavelet networks based on the Fast Wavelet Transform (FWT) is proposed. It has many advantages compared to other algorithms, in which we solve the problem in previous works, when the weights of the hidden layer to the output layer are determined by applying the back propagation algorithm or by direct solution which requires to compute the matrix inversion, this may cause intensive computation when the learning data is too large. However, the new algorithm is realized by iterative application of FWT to compute the connection weights. Furthermore, we have extended the novel learning algorithm by using Levenberg–Marquardt method to optimize the learning functions. The experimental results have demonstrated that our model is remarkably more refreshing than some of the previously established models in terms of both speed and efficiency.
SPAM DETECTION USING GENETIC ASSISTED ARTIFICIAL IMMUNE SYSTEM
Authors: ZITAR RAED ABU , MOHAMMAD ADEL HAMDAN
Published: January 2012

This work presents a novel system based on artificial immune system for spam detection. A relatively new machine learning method inspired by the human immune system called Artificial Immune System (AIS) has been emerging recently. This method is currently undergoing intense investigation and demonstration. Core modifications were applied on the standard AIS with the aid of the Genetic Algorithm (GA). SpamAssassin corpus is used in all our simulations. Spam is a serious universal problem which causes problems for almost all computer users. This issue affects not only normal users of the internet, but also causes problems for companies and organizations due to expensive costs in lost productivity, wasting users' time and network bandwidth. Many studies on spam indicate that it costs organizations billions of dollars annually. We introduce a GA assisted AIS in spam detection, and compare between two methods. Encouraging results were achieved when comparing to commercially available anti-spam software.
SYNCHRONIZATION AND BIFURCATION IN LIMIT CYCLE OSCILLATORS WITH DELAYED COUPLINGS
Authors: PENG JIAN , WANG LIANHUA , ZHAO YUEYU , GUO SHANGJIANG
Published: January 2012

In this paper, a system of three globally coupled limit cycle oscillators with a linear time-delayed coupling are investigated. Considering the delay as a parameter, we also study the effect of time delay on the dynamics. Next, Hopf bifurcations induced by time delays using the normal form theory and center manifold reduction are obtained. Based on the symmetric Hopf bifurcation theorem, we investigate stable phase-locking and unstable waves. Then later, the directions of Hopf bifurcations are determined in some region, where stability switches may occur. The results show that the bifurcating periodic solutions are orbitally asymptotically stable. Numerical simulations are applied to verify the theoretical predictions.
UNCERTAINTY OF PULSE ENERGY CONVERSION SYSTEM DYNAMICS NEAR BIFURCATION BOUNDARY
Authors: KOLOKOLOV YURY , MONOVSKAYA ANNA , USTINOV PAVEL , ESSOUNBOULI NAJIB , HAMZAOUI ABDELAZIZ
Published: January 2012

The paper is devoted to the problem of uncertainty in the behavior of a pulse energy conversion system (PECS) near the bifurcation boundary. As a result of the investigations, the magnitude of the zone within which a heightened sensitivity of system dynamics varying to external and internal disturbances is revealed. Also the phenomenon of intermittency is confirmed. The validity of the results is based on an analysis of the synchronized data presented by oscillograms, bifurcation diagrams and time series, acquired on the experimental setup of DC motor drive (2 kW) with pulse-width modulation.
DYNAMICS OF MONOTONE GRAPH, DENDRITE AND DENDROID MAPS
Authors: NAGHMOUCHI ISSAM
Published: January 2012

We show that, for monotone graph map f, all the ω-limit sets are finite whenever f has periodic point and for monotone dendrite map, any infinite ω-limit set does not contain periodic points. As a consequence, monotone graph and dendrite maps have no Li–Yorke pairs. However, we built a homeomorphism on a dendroid with a scrambled set having nonempty interior.
PERIOD DOUBLING RENORMALIZATION FOR AREA-PRESERVING MAPS AND MILD COMPUTER ASSISTANCE IN CONTRACTION MAPPING PRINCIPLE
Authors: GAIDASHEV DENIS G.
Published: January 2012

A universal period doubling cascade analogous to the famous Feigenbaum–Coullet–Tresser period doubling has been observed in area-preserving maps of ℝ2. The existence of the "universal" map with orbits of all binary periods has been proved via a renormalization approach in [Eckmann et al., 1984] and [Gaidashev et al., 2011]. These proofs use "hard" computer assistance.

In this paper, we attempt to reduce computer assistance in the argument, and present a mild computer aided proof of the analyticity and compactness of the renormalization operator in a neighborhood of a renormalization fixed point: that is, a proof that does not use generalizations of interval arithmetics to functional spaces — but rather relies on interval arithmetics on real numbers only to estimate otherwise explicit expressions. The proof relies on several instances of the Contraction Mapping Principle, which is, again, verified via mild computer assistance.
APPROACH OF A CLASS OF DISCONTINUOUS DYNAMICAL SYSTEMS OF FRACTIONAL ORDER: EXISTENCE OF SOLUTIONS
Authors: DANCA MARIUS-F.
Published: January 2012

In this paper, we are concerned with the possible approach to the existence of solutions for a class of discontinuous dynamical systems of fractional order. To this purpose, the underlying initial value problem is transformed into a fractional set-valued problem. Next, Cellina's Theorem is applied leading to a single-valued continuous initial value problem of fractional order. The existence of solutions is assured by a Péano-like theorem for ordinary differential equations of fractional order.
EXACT HOMOCLINIC ORBITS AND HETEROCLINIC FAMILIES FOR A THIRD-ORDER SYSTEM IN THE CHAZY CLASS XI (N = 3)
Authors: LI JIBIN , CHEN FENGJUAN
Published: January 2012

For a differential equation in the Chazy class XI (N = 3), the corresponding three-dimensional system is studied by using dynamical system methods and Cosgrove's results. In all level sets, the exact explicit parametric representations of homoclinic orbits, the families of heteroclinic orbits and periodic orbits, as well as the families of unbounded solutions are obtained.
THE EXPLICIT NONLINEAR WAVE SOLUTIONS AND THEIR BIFURCATIONS OF THE GENERALIZED CAMASSA–HOLM EQUATION
Authors: LIU ZHENGRONG , LIANG YONG
Published: January 2012

In this paper, we study the explicit nonlinear wave solutions and their bifurcations of the generalized Camassa–Holm equation [Formula: see text]

Not only are the precise expressions of the explicit nonlinear wave solutions obtained, but some interesting bifurcation phenomena are revealed.

Firstly, it is verified that k = 3/8 is a bifurcation parametric value for several types of explicit nonlinear wave solutions.

When k < 3/8, there are five types of explicit nonlinear wave solutions, which are

(i) hyperbolic peakon wave solution,

(ii) fractional peakon wave solution,

(iii) fractional singular wave solution,

(iv) hyperbolic singular wave solution,

(v) hyperbolic smooth solitary wave solution.

When k = 3/8, there are two types of explicit nonlinear wave solutions, which are fractional peakon wave solution and fractional singular wave solution.

When k > 3/8, there is not any type of explicit nonlinear wave solutions.

Secondly, it is shown that there are some bifurcation wave speed values such that the peakon wave and the anti-peakon wave appear alternately.

Thirdly, it is displayed that there are other bifurcation wave speed values such that the hyperbolic peakon wave solution becomes the fractional peakon wave solution, and the hyperbolic singular wave solution becomes the fractional singular wave solution.
BIFURCATION AND CHAOS IN THE TINKERBELL MAP
Authors: YUAN SHAOLIANG , JIANG TAO , JING ZHUJUN
Published: January 2012

In this paper, the dynamical behaviors of the Tinkerbell map are investigated in detail. Conditions for the existence of fold bifurcation, flip bifurcation and Hopf bifurcation are derived, and chaos in the sense of Marotto is verified by both analytical and numerical methods. Numerical simulations include bifurcation diagrams in two- and three-dimensional spaces, phase portraits, and the maximum Lyapunov exponent and fractal dimension, as well as the distribution of dynamics in the parameter plane, which exhibit new and interesting dynamical behaviors. More specifically, this paper reports the findings of chaos in the sense of Marotto, a route from an invariant circle to transient chaos with a great abundance of periodic windows, including period-2, 7, 8, 9, 10, 13, 17, 19, 23, 26 and so on, and suddenly appearing or disappearing chaos, convergence of an invariant circle to a period-one orbit, symmetry-breaking of periodic orbits, interlocking period-doubling bifurcations in chaotic regions, interior crisis, chaotic attractors, coexisting (2, 10, 13) chaotic sets, two coexisting invariant circles, two attracting chaotic sets coexisting with a non-attracting chaotic set, and so on, all in the Tinkerbell map. In particular, it is found that there is no obvious road from period-doubling bifurcations to chaos, but there is a route from a period-one orbit to an invariant circle and then to transient chaos as the parameters are varied. Combining the existing results in the current literature with the new results reported in this paper, a more complete understanding of the Tinkerbell map is obtained.
ENTROPY SPECTRA OF SINGLE HORIZON BLACK HOLES IN TWO DIMENSIONS
Authors: LÓPEZ-ORTEGA A.
Published: January 2012

The Hod conjecture proposes that the asymptotic quasinormal frequencies determine the entropy quantum of a black hole. Considering the Maggiore modification of this conjecture, we calculate the entropy spectra of general, single horizon, asymptotically flat black holes in two-dimensional dilaton gravity. We also compute the entropy quanta of the two-dimensional Witten and AdS2 black holes. Using the results for the entropy quanta of these two-dimensional black holes, we discuss whether the produced values are generic. Finally we extend the results on the entropy spectra of other black holes.
PSEUDO-COMPLEX GENERAL RELATIVITY
Authors: CASPAR GUNTHER , SCHÖNENBACH THOMAS , GREINER WALTER , HESS PETER O.
Published: January 2012

An algebraic extension of General Relativity is presented, which introduces pseudo-complex coordinates. We give a short review on the properties of pseudo-complex variables and their advantage of their use in field theory. Afterwards we extend General Relativity to pseudo-complex variables. The projection to real results is described and in particular the pseudo-complex Schwarzschild solution is discussed.
PHASE SPACE OF ANISOTROPIC Rn COSMOLOGIES
Authors: LEON GENLY
Published: January 2012

We construct general anisotropic cosmological scenarios governed by an f(R) = Rn gravitational sector. Focusing then on some specific geometries, and modelling the matter content as a perfect fluid, we perform a phase-space analysis. We analyze the possibility of accelerating expansion at late times, and additionally, we determine conditions for the parameter n for the existence of phantom behavior, contracting solutions as well as of cyclic cosmology. Furthermore, we analyze if the universe evolves towards the future isotropization without relying on a cosmic no-hair theorem. Our results indicate that anisotropic geometries in modified gravitational frameworks present radically different cosmological behaviors compared to the simple isotropic scenarios.
INSTABILITIES IN KERR SPACETIMES
Authors: DOTTI GUSTAVO , GLEISER REINALDO J. , RANEA-SANDOVAL IGNACIO F.
Published: January 2012

We present a generalization of previous results regarding the stability under gravitational perturbations of nakedly singular super extreme Kerr spacetime and Kerr black hole interior beyond the Cauchy horizon. To do so we study solutions to the radial and angular Teukolsky's equations with different spin weights, particulary s = ±1 representing electromagnetic perturbations, s = ±1/2 representing a perturbation by a Dirac field and s = 0 representing perturbations by a scalar field. By analizing the properties of radial and angular eigenvalues we prove the existence of an infinite family of unstable modes.
MAGNETIC EXPLOSIONS, WITH APPLICATION TO SOLAR FLARES AND TO MAGNETAR OUTBURSTS
Authors: MELROSE DONALD B.
Published: January 2012

An accepted model for magnetospheric substorms is used as the basis for a generic model for magnetic explosions, Emphasis is placed on the role of the inductive electric field and the displacement current. It is pointed out that these are unjustifiably neglected in conventional models, with this neglect being implicit in the assumptions of magnetohydrodynamics. Consequences of including the inductive electric field are identified. Fiducial numbers for the application of the generic model to solar flares and magnetar outbursts are suggested.
GAS-INDUCED MERGER OF MASSIVE BLACK HOLE BINARIES
Authors: ESCALA ANDRES , VALLE LUCIANO DEL
Published: January 2012

We use SPH simulations to investigate the effects of gas on the inspiral and merger of massive black hole binary. This scenario is motivated by the very massive nuclear gas disk observed in the central regions of merging galaxies. We run a variety of models, ranging from simulations with relaty smooth gas to cases in which the gas has a more clumpy spatial distribution. We also vary the Mgas / Mbin ratio identifying the case M bin /M gas = 1 as an important limiting test-case for the analytic formulation of the dynamical process that dominates the binary-disk interaction in the late evolution of the system. We find that gas has an important effect in the evolution of interacting massive black hole binary on merging galaxies and that this interaction can be separate in two principal stages. The coalescence timescale that we find for the MBH binary varies between 5 · 106 yr and 2.5 · 107 yr for typical parameters of ULIRGs galaxies. This results supports scenarios of massive black hole evolution and growth in which hierarchical merging plays an important role. The final coalescence of the black hole leads to gravitational radiation emission that would be detected out to high redshift by LISA.
RECENT RESULTS FROM THE PIERRE AUGER OBSERVATORY
Authors:   for the Pierre Auger Collaboration: Full author list available in, DOBRIGKEIT CAROLA
Published: January 2012

The Pierre Auger Observatory in Argentina is the largest cosmic ray detector array ever built. Its main goal is to measure cosmic rays of energy above 1018 eV with unprecedented statistics and precision. Although the construction of its baseline design was completed in mid-2008, the Observatory has been taking data continuously since January 2004. The main results obtained with the Pierre Auger Observatory are presented, with emphasis on the energy spectrum and studies of composition and arrival directions of the ultrahigh energy cosmic rays. Features observed in the energy spectrum are discussed. Results about cosmic ray composition inferred from systematic studies of the average depth of shower maximum and its fluctuations are reviewed. Recent results of studies of arrival direction distributions and correlations with nearby extragalactic objects are presented.
ON THE MAXIMUM MASS OF GENERAL RELATIVISTIC UNIFORMLY ROTATING WHITE DWARFS
Authors: BOSHKAYEV KUANTAY , RUEDA JORGE , RUFFINI REMO
Published: January 2012

The properties of uniformly rotating white dwarfs are analyzed within the framework of general relativity. Hartle's formalism is applied to construct self-consistently the internal and external solutions to the Einstein equations. The mass, the radius, the moment of inertia and quadrupole moment of rotating white dwarfs have been calculated as a function of both the central density and rotation period of the star. The maximum mass of rotating white dwarfs for stable configurations has been obtained.
QUARK MATTER NUCLEATION AT NEUTRON STAR CORES: RELEVANCE OF ENERGY-DENSITY FLUCTUATIONS
Authors: LUGONES GERMAN , GRUNFELD ANA G.
Published: January 2012

We study the deconfinement of hadronic matter into quark matter in a protoneutron star focusing on the effects of the finite size on the formation of just-deconfined color superconducting quark droplets embedded in the hadronic environment. We show that energy-density fluctuations are much more relevant for deconfinement than temperature and neutrino density fluctuations. We calculate the critical size spectrum of energy-density fluctuations that allows deconfinement as well as the nucleation rate of each critical bubble. We find that drops with any radii smaller than 800 fm can be formed at a huge rate when matter achieves the bulk transition limit of 5–6 times the nuclear saturation density.
GLUONS IN THE STARS
Authors: FOGAÇA DAVID A. , FRANZON BRUNO , NAVARRA FERNANDO S.
Published: January 2012

Using an equation of state based on a mean-field approximation for QCD to describe the cold quark gluon plasma we study stellar structures of compact stars which are compatible with recent astrophysical data.1
GEOMETRIC SCALING IN ULTRAHIGH ENERGY NEUTRINOS AND NONLINEAR PERTURBATIVE QCD
Authors: MACHADO MAGNO V. T.
Published: January 2012

The ultrahigh energy neutrino cross section is a crucial ingredient in the calculation of the event rate in high energy neutrino telescopes. Currently there are several approaches which predict different behaviors for its magnitude for ultrahigh energies. In this contribution is presented a summary of current predictions based on the non-linear QCD evolution equations, the so-called perturbative saturation physics. In particular, predictions are shown based on the parton saturation approaches and the consequences of geometric scaling property at high energies are discussed. The scaling property allows an analytical computation of the neutrino scattering on nucleon/nucleus at high energies, providing a theoretical parameterization.
ON THE COOLING MYSTERY OF THE NEUTRON STAR IN THE CASSIOPEIA A SUPERNOVA REMNANT
Authors: PÉREZ ROJAS HUGO , MARTÍNEZ AURORA PÉREZ , MESQUITA ALEXANDRE , RAZEIRA MOISÉS , GOMES ROSANA O. , VASCONCELLOS CÉSAR A.Z.
Published: January 2012

By considering the expression for the total neutrino luminosity, Lν, in terms of the neutrino total emissivity and the volume of a neutron star, we confirm that indeed the luminosity for the direct URCA processes has a dependence on temperature of order T6 as assumed by Heinke and Ho. However, as can be seen in our formulation, Lν depends also on a variety of ingredients that characterize properties of dense nuclear matter as baryon effective masses, Fermi momenta and energy, as well as parameters that characterize the weak interaction beta process. In particular, the dependence of the luminosity of neutrinos in the effective mass of baryons that make up a neutron star opens a new perspective on the study of properties of dense nuclear matter. The model adopted in our calculations may represent, we believe, a further step in elucidating the mysteries surrounding the cooling of Cassiopeia A. Work along this line is in progress
STRUCTURE AND THERMAL EVOLUTION OF SPINNING-DOWN NEUTRON STARS
Authors: NEGREIROS RODRIGO , SCHRAMM STEFAN , WEBER FRIDOLIN
Published: January 2012

In this paper we address the effects of spin-down on the cooling of neutron stars. During its evolution, stellar composition and structure might be substantially altered, as a result of spin-down and the consequent density increase. Since the timescale of cooling might be comparable to to that of the spin-evolution, the modifications to the structure/composition might have important effects on the thermal evolution of the object. We show that the direct Urca process might be delayed or supressed, when spin-down is taken into account. This leads to neutron stars with slow cooling, as opposed to enhanced cooling as would be the case if a "froze-in" structure and composition were considered. In conclusion we demonstrate that the inclusion of spin-down effects on the cooling of neutron stars have far-reaching implications for the interpretation of pulsars.
TWO MEASURES THEORY APPROACH TO BAGS AND CONFINEMENT
Authors: GUENDELMAN EDUARDO I.
Published: January 2012

We consider the question of bags and confinement in the framework of a theory which uses two volume elements [Formula: see text] and Φd4x, where Φ is a metric independent density. For scale invariance a dilaton field Φ is considered. Using the first order formalism, curvature (ΦR and [Formula: see text]) terms, gauge field term ([Formula: see text] and [Formula: see text]) and dilaton kinetic terms are introduced in a conformally invariant way. Exponential potentials for the dilaton break down (softly) the conformal invariance down to global scale invariance, which also suffers s.s.b. after integrating the equations of motion. The model has a well defined flat space limit. As a result of the s.s.b. of scale invariance phases with different vacuum energy density appear. Inside the bags the gauge dynamics is normal, that is non confining, while for the outside, the gauge field dynamics is confining.
EXTENSION OF THE PERIODIC SYSTEM: SUPERHEAVY, SUPERSTRANGE, ANTIMATTER NUCLEI
Authors: KARPOV ALEXANDER , ZAGREBAEV VALERY , GREINER WALTER
Published: January 2012

The extension of the periodic system into various new areas is investigated. Experiments for the synthesis of superheavy elements and the predictions of magic numbers are reviewed. Further on, investigations on hypernuclei and the possible production of antimatter-clusters in heavy-ion collisions are reported. Various versions of the meson field theory serve as effective field theories at the basis of modern nuclear structure and suggest structure in the vacuum which might be important for the production of hyper- and antimatter.
GLUEBALL-DILATON AS AN ALTERNATIVE TO DARK MATTER IN NEUTRON STARS
Authors: VASCONCELLOS C. A. Z. , MESQUITA A. , RAZEIRA M. , HADJIMICHEF D. , COSTA J. E.
Published: January 2012

We study cold nuclear matter based on a mean field description of baryons bound by the exchange of scalar-isoscalar, vector-isoscalar, scalar-isovector and vector-isovector meson fields as well as the glueball field. For this task, we use an extended version of the effective model with derivative couplings with genuine many-body forces simulated by nonlinear self-couplings and meson-meson interaction terms involving scalar-isoscalar (σ, σ*), vector-isoscalar (ω, ɸ), vector-isovector (ϱ), scalar-isovector (δ) meson and the glueball fields. In our approach, the realization of the broken scale invariance of quantum chromodynamics is achieved through the introduction of a dilaton field. The effective model with dilatons is the applied to the description of neutron stars.
ASSESSING THE EXISTENCE OF AN ENTREPRENEURIAL PROCESS AT FURTHER EDUCATION AND TRAINING COLLEGES IN KWAZULU-NATAL
Authors: CHAPMAN GAVIN ASHLEY , SINGH SHALINI
Published: January 2012

FET colleges are integral centres of learning to provide students with vocational learning opportunities. This paper examined if FET colleges in Kwazulu-Natal were aware of an entrepreneurial culture that could assist them in supplementing their income to become less dependent upon the State for operational subsidies. A quantitative study with a sample size of 100 candidates was undertaken. The study revealed that although there is an awareness of entrepreneurial activities, there is a weakness in the application of an entrepreneurial process at FET colleges.
AFFECT: HOW DOES IT INFLUENCE ONE'S ENTREPRENEURIAL COGNITIONS?
Authors: WALKER SEAN
Published: January 2012

Speculation to the antecedents of an entrepreneurs' superior ability to recognize and exploit opportunities has been prominent in the entrepreneurship literature. Research is now turning more toward the cognitive antecedents (affect). Stemming from the theoretical contribution of Baron (2008), this article tested the ability of positive/negative affect to subliminally prime individuals via a parafoveal vigilance task in an attempt to influence their entrepreneurial cognitions. Through the utilization of both static and longitudinal measures, the findings show that one's entrepreneurial cognitions can be influenced subliminally. Implications and future directions are discussed.
AN "ACTIVATION" PROCESS FOR ENTREPRENEURIAL ENGINEERING EDUCATION: THE MODEL AND APPLICATION
Authors: ELIA GIANLUCA , MARGHERITA A. , SECUNDO G. , MOUSTAGHFIR K.
Published: January 2012

The pervasiveness of scientific developments has raised the role of entrepreneurship as a driver of socio-economic value. Higher education institutions are thus asked to create entrepreneurial mindset and competencies with the purpose to make students people able to proactively identify opportunities and transform them in market solutions. In particular, engineering education programs can be of relevance to develop technology entrepreneurship competencies through hands-on and experiential approaches. In such vein, this paper proposes a model of entrepreneurship education as an "activation" process which uses four critical levers with the purpose to infuse the essence of entrepreneurship in tomorrow's engineering professionals. The application of the model is exemplified through the analysis of a research training program grounded in the aerospace domain. The key features of the initiative are discussed in the perspective of exploring new models of entrepreneurial engineering education.
COUNTRY ENTREPRENEURIAL PROFILES: ASSESSING THE INDIVIDUAL AND ORGANIZATIONAL LEVELS OF ENTREPRENEURSHIP ACROSS COUNTRIES
Authors: MARCOTTE CLAUDE
Published: January 2012

Up to now, the focus in comparative international entrepreneurship has been on individual-level indicators of entrepreneurial activity, such as nascent entrepreneurship and small business ownership. However, measuring only the individual component of entrepreneurship appears conceptually incomplete, as it leaves out other important ones, the most obvious being the organizational component. Countries may have different entrepreneurship profiles, depending on the allocation of entrepreneurial endeavors across various levels and dimensions. To augment the content validity of current measurements, this paper aims to integrate and compare individual and organizational indicators of entrepreneurial activity in 22 member countries of the Organization for Economic Co-operation and Development (OECD). The inclusion of corporate entrepreneurship indicators, derived from the entrepreneurial orientation concept, modified substantially the country rankings based only on small business ownership rates. A significant negative relationship was found between individual and corporate indicators.
Impacts, recovery and resilience of Thai tourist coasts to the 2004 Indian Ocean Tsunami
Authors: Wong Poh Poh
Published: January 2012

A powerful earthquake off Sumatra on 26 December 2004 set off the most disastrous tsunami to impact on the coasts and coastal communities of the Indian Ocean. Coastal tourism in Thailand, Sri Lanka and the Maldives was significantly affected. Examples from Phuket Island, Khao Lak and Ko Phi Phi Don, Thailand, show the variation in the impacts, recovery and resilience of Thai tourist coasts, focusing primarily on beach recovery and the reconstruction of the tourist industry. As priority was given to Phuket Island, tourism recovered after 1 year. Khao Lak was the worst affected and has yet to fully recover. Ko Phi Phi Don recovered but is plagued by land-use problems. Various mitigation measures have been implemented to increase the resilience of the tourist coasts. However, the resilience of the Thai tourist coasts in the event of a future tsunami is questionable.
Influence of the institutional and socio-economic context for responding to disasters: case study of the 1994 and 2006 eruptions of the Merapi Volcano, Indonesia
Authors: Mei Estuning Tyas Wulan , Lavigne Franck
Published: January 2012

This article explores the institutional responses to the volcanic crises and related problems encountered during the 1994 and 2006 eruptions of the Merapi Volcano, Indonesia. It also illustrates traditional responses to the volcanic crisis led by the local community and provides recommendations to encourage a comprehensive institutional volcanic crisis management including community-based response. This study aims to understand and to explain the gap between institutional responses and the community's perception during pre- to post-crisis situations. Interviews, questionnaires and focus group discussions revealed that top-down institutional responses to the volcanic crisis are not fully appropriate in regions with a high cultural perception. Working with the community is an ideal solution to minimize the gap between the government, scientists, non-governmental organizations and the community itself. A community-based methodology combined with natural hazard studies generates comprehensive risk and crisis management.
Records of submarine natural hazards off SW Taiwan
Authors: Su Chih-Chieh , Tseng Jing-Yi , Hsu Ho-Han , Chiang Cheng-Shing , Yu Ho-Shing , Lin Saulwood , Liu James T.
Published: January 2012

In the past few years, large earthquakes and torrential rain hit southern Taiwan and induced severe submarine hazards off the SW coast. Marine sediments (turbidites) provide valuable records with which to study and understand the formation of these submarine geo-hazards. The Pingtung Earthquake (two major events (
M
L
=7.0) plus many aftershocks), on 26 December 2006, triggered turbidity currents that severed submarine cables in the Fangliao and Gaoping submarine canyons. This caused significant economic loss. In addition to earthquake activity, typhoons and torrential rains that induced flooding are also important mechanisms responsible for the formation of turbidites. On 8–9 August 2009 Typhoon Morakot brought heavy rains to southern Taiwan, causing serious landslides and flooding on land. The typhoon also caused submarine cable breaks in the Gaoping Canyon. All such events are likely to be recorded in the marine sediments of the canyon system, and by analysing these records we may be able to reconstruct the history of past earthquakes and floods in the region. Chirp sonar profiles, in conjunction with core analysis, including X-ray radiographs, grain size and
210
Pb analysis, are used to identify the sources, transport and deposition of the turbidites (or hyperpycnite) and to reconstruct the history of earthquakes and flooding in the study area. Results indicate that these submarine hazards are not only related to earthquake and floods but that the unique geological and hydrological setting also plays an important role in the initiation of these submarine geo-hazards.
Bedding structures in Indian tsunami deposits that provide clues to the dynamics of tsunami inundation
Authors: Switzer Adam D. , Srinivasalu S. , Thangadurai N. , Ram Mohan V.
Published: January 2012

The 2004 Indian Ocean tsunami deposited an extensive sandsheet on the coastal plain of SE India. At particular sites, the sedimentary bedding in the sandsheet provides evidence of variable energy conditions and flow during inundation of the coast. Trenching of the deposits at sites where only unidirectional flow was observed allowed the investigation of changes in hydrodynamics recorded in bedding structures without the added complexity of return flows and reworking. A high-velocity initial surge is recorded as upper flow regime (UFR) plane bedding. Following the initial high flow a period of falling flow velocity and quiescence occurs where sediments settle out of suspension, often resulting in a reverse graded bed that transitions to a graded (fining-up) bed. As water levels begin to decline after maximum inundation sheet flow caused the formation of inversely graded (coarsening-up) beds or a return to UFR conditions. At one site the final stages of tsunami inundation is recorded as small channels that have an erosional base and are filled with graded sediments that exhibit complex patterns of sedimentation. Pits excavated in areas of unidirectional flow allow the development of a sedimentary model for tsunami sediment dynamics across flat topography under unidirectional flow conditions.
Tsunami hazard related to a flank collapse of Anak Krakatau Volcano, Sunda Strait, Indonesia
Authors: Giachetti T. , Paris R. , Kelfoun K. , Ontowirjo B.
Published: January 2012

Numerical modelling of a rapid, partial destabilization of Anak Krakatau Volcano (Indonesia) was performed in order to investigate the tsunami triggered by this event. Anak Krakatau, which is largely built on the steep NE wall of the 1883 Krakatau eruption caldera, is active on its SW side (towards the 1883 caldera), which makes the edifice quite unstable. A hypothetical 0.280 km
3
flank collapse directed southwestwards would trigger an initial wave 43 m in height that would reach the islands of Sertung, Panjang and Rakata in less than 1 min, with amplitudes from 15 to 30 m. These waves would be potentially dangerous for the many small tourist boats circulating in, and around, the Krakatau Archipelago. The waves would then propagate in a radial manner from the impact region and across the Sunda Strait, at an average speed of 80–110 km h
−1
. The tsunami would reach the cities located on the western coast of Java (e.g. Merak, Anyer and Carita.) 35–45 min after the onset of collapse, with a maximum amplitude from 1.5 (Merak and Panimbang) to 3.4 m (Labuhan). As many industrial and tourist infrastructures are located close to the sea and at altitudes of less than 10 m, these waves present a non-negligible risk. Owing to numerous reflections inside the Krakatau Archipelago, the waves would even affect Bandar Lampung (Sumatra,
c
. 900 000 inhabitants) after more than 1 h, with a maximum amplitude of 0.3 m. The waves produced would be far smaller than those occurring during the 1883 Krakatau eruption (
c.
15 m) and a rapid detection of the collapse by the volcano observatory, together with an efficient alert system on the coast, would possibly prevent this hypothetical event from being deadly.
An examination of hazard communication logs and public response during the 1946 and 1960 tsunamis that impacted Hilo, Hawaii
Authors: Johnston Jeanne B. , Bird Deanne K. , Goff James R. , Dudley Walter C.
Published: January 2012

This paper examines communication methods used to inform the vulnerable community of Hilo, Hawaii of the impending tsunamis that struck in 1946 and 1960. These tsunamis caused tragic loss of life and enormous economic damage in Hilo and along the shores of the Hawaiian Island chain. Over 12 h notice of a possible large tsunami was given in 1960
and
the siren warning system sounded more than 4 h prior to the event. The government agencies knew there was a tsunami alert and the media were broadcasting warnings. However, the 1960 tsunami took the lives of 61 people in Hilo only 14 years after 96 people were killed during the 1946 event. In order to discover why so many people perished, government agency logs recorded during the 1960 tsunami were examined and personal accounts from survivors of both the 1946 and 1960 tsunamis were analysed. Contributing to the tragic loss of life was a lack of communication between government agencies in addition to media inaccuracies and a public that was not educated in tsunami safety. Effective tsunami mitigation can only be accomplished through continual tsunami awareness education for the public, media and emergency personnel, and with accurate and timely tsunami warnings.
Towards better design and management of tsunami evacuation routes: a case study of Ao Jak Beach Road
Authors: Ziegler Alan D. , Sidle Roy C. , Song Mandy S. , Ang Zuo Jin , Duangnamon Decha
Published: January 2012

Among the thousands of people killed or reported missing in Thailand during the 2004 Indian Ocean Tsunami were villagers in small communities on the Andaman Coast. A combination of factors contributed to loss of life, including the lack of defined evacuation routes. This vulnerability to tsunami attacks has recently been addressed with the demarcation of evacuation routes, along both well-maintained arteries and native surface (unpaved) roads. However, poor location design and irregular maintenance will reduce the lifetime that the latter can provide safe egress from remote coastlines. In this work we identified 10 major gullies and 18 landslides along a critical 0.5 km section of a tsunami evacuation road accessing a remote beach of the Andaman Coast in southern Thailand. Erosion rates from landslides and gullies approached 9500 Mg ha
−1
in less than a year following widening of the road. Importantly, the degradation features, landslides in particular, reduced the effectiveness of the road to serve as a safe passageway to escape future tsunamis or large storm surges. This study demonstrates that greater attention should be given to appropriate road location, design and maintenance in integrated programmes aimed at reducing tsunami vulnerability in remote coastal areas, not only on the Andaman Coast, but worldwide.
Validated computation of certain hypergeometric functions
Authors: Colman Michel , Cuyt Annie , Deun Joris Van
Published: January 2012

We present an efficient algorithm for the validated high-precision computation of real continued fractions, accurate to the last digit. The algorithm proceeds in two stages. In the first stage, computations are done in double precision. A forward error analysis and some heuristics are used to obtain an a priori error estimate. This estimate is used in the second stage to compute the fraction to the requested accuracy in high precision (adaptively incrementing the precision for reasons of efficiency). A running error analysis and techniques from interval arithmetic are used to validate the result.

As an application, we use this algorithm to compute Gauss and confluent hypergeometric functions when one of the numerator parameters is a positive integer.
A note on shifted Hessenberg systems and frequency response computation
Authors: Beattie Christopher , Drmač Zlatko , Gugercin Serkan
Published: January 2012

In this article, we propose a numerical algorithm for efficient and robust solution of a sequence of shifted Hessenberg linear systems. In particular, we show how the frequency response 𝒢(σ) =
d
-
C
(
A
-σ I)
-1
b
in the single input case can be computed more efficiently than with other state-of-the-art methods. We also provide a backward stability analysis of the proposed algorithm.
Algorithms and data structures for massively parallel generic adaptive finite element codes
Authors: Bangerth Wolfgang , Burstedde Carsten , Heister Timo , Kronbichler Martin
Published: January 2012

Today's largest supercomputers have 100,000s of processor cores and offer the potential to solve partial differential equations discretized by billions of unknowns. However, the complexity of scaling to such large machines and problem sizes has so far prevented the emergence of generic software libraries that support such computations, although these would lower the threshold of entry and enable many more applications to benefit from large-scale computing.

We are concerned with providing this functionality for mesh-adaptive finite element computations. We assume the existence of an “oracle” that implements the generation and modification of an adaptive mesh distributed across many processors, and that responds to queries about its structure. Based on querying the oracle, we develop scalable algorithms and data structures for generic finite element methods. Specifically, we consider the parallel distribution of mesh data, global enumeration of degrees of freedom, constraints, and postprocessing. Our algorithms remove the bottlenecks that typically limit large-scale adaptive finite element analyses.

We demonstrate scalability of complete finite element workflows on up to 16,384 processors. An implementation of the proposed algorithms, based on the open source software p4est as mesh oracle, is provided under an open source license through the widely used deal.II finite element software library.
Algorithm 916
Authors: Zaghloul Mofreh R. , Ali Ahmed N.
Published: January 2012

We present a MATLAB function for the numerical evaluation of the Faddeyeva function
w
(
z
). The function is based on a newly developed accurate algorithm. In addition to its higher accuracy, the software provides a flexible accuracy vs efficiency trade-off through a controlling parameter that may be used to reduce accuracy and computational time and vice versa. Verification of the flexibility, reliability, and superior accuracy of the algorithm is provided through comparison with standard algorithms available in other libraries and software packages.
Technology-mediated social arrangements to resolve breakdowns in infrastructure during ongoing disruption
Authors: Semaan Bryan , Mark Gloria
Published: January 2012

When societies experience disruption as caused by natural disasters, various official government agencies, relief organizations, and emergent citizen groups engage in activities that aid in the recovery effort—the process that leads to the resumption of normal life. In war environments however, societal trust can be affected and people may develop distrust of the institutions and associated individuals that provide and resolve breakdowns in infrastructure. This article reports on an ethnographic study of the use of information and communication technologies (ICTs) by citizens experiencing ongoing disruption in a conflict zone. We conducted 90 semistructured interviews with Iraqi civilians who experienced the 2
nd
Gulf War beginning in March 2003. We show how citizens used ICTs to continuously resolve breakdowns in infrastructure during ongoing disruption caused by the conflict, by creating new, reliable technology-mediated social arrangements that enabled people to maintain daily routines for travel, education, and obtaining information. We then discuss new ways to think about infrastructure and implications for the disaster relief effort.
Efficient Testing of Recovery Code Using Fault Injection
Authors: Marinescu Paul D. , Candea George
Published: January 2012

A critical part of developing a reliable software system is testing its recovery code. This code is traditionally difficult to test in the lab, and, in the field, it rarely gets to run; yet, when it does run, it must execute flawlessly in order to recover the system from failure. In this article, we present a library-level fault injection engine that enables the productive use of fault injection for software testing. We describe automated techniques for reliably identifying errors that applications may encounter when interacting with their environment, for automatically identifying high-value injection targets in program binaries, and for producing efficient injection test scenarios. We present a framework for writing precise triggers that inject desired faults, in the form of error return codes and corresponding side effects, at the boundary between applications and libraries. These techniques are embodied in LFI, a new fault injection engine we are distributing http://lfi.epfl.ch. This article includes a report of our initial experience using LFI. Most notably, LFI found 12 serious, previously unreported bugs in the MySQL database server, Git version control system, BIND name server, Pidgin IM client, and PBFT replication system with no developer assistance and no access to source code. LFI also increased recovery-code coverage from virtually zero up to 60% entirely automatically without requiring new tests or human involvement.
Depot
Authors: Mahajan Prince , Setty Srinath , Lee Sangmin , Clement Allen , Alvisi Lorenzo , Dahlin Mike , Walfish Michael
Published: January 2012

This article describes the design, implementation, and evaluation of Depot, a cloud storage system that minimizes trust assumptions. Depot tolerates buggy or malicious behavior by
any number
of clients or servers, yet it provides safety and liveness guarantees to correct clients. Depot provides these guarantees using a two-layer architecture. First, Depot ensures that the updates observed by correct nodes are consistently ordered under Fork-Join-Causal consistency (FJC). FJC is a slight weakening of causal consistency that can be both safe and live despite faulty nodes. Second, Depot implements protocols that use this consistent ordering of updates to provide other desirable consistency, staleness, durability, and recovery properties. Our evaluation suggests that the costs of these guarantees are modest and that Depot can tolerate faults and maintain good availability, latency, overhead, and staleness even when significant faults occur.
Including Accident Information in Automatic Bicycle Route Planning for Urban Areas
Authors: Singleton Alex D. , Lewis Daniel J.
Published: January 2012

Between 2005 and 2007 there were 9071 traffic accidents involving bicycles within London and this paper demonstrates the utility of Geographic Information Systems as a tool for analysing and visualising these occurrences. Through linkage of these spatial locations to a street network dataset it was possible to create a variety of intelligence about the types of street infrastructure where accidents predominantly occur. Additionally, a network routing algorithm was adapted to account for the frequency of accidents within a series of proposed journeys. This pilot routing application compared the quickest route with an accident avoidance weighted route between a series of origins and destinations. The results demonstrated that the routes avoiding areas of high accident volume did not increase journey length significantly; however they did provide a “safer” route based on empirical evidence over the volume of accident locations.
Successful Treatment of Refractory Wart with a Topical Activated Vitamin D in a Renal Transplant Recipient
Authors: Moscarelli Luciano , Annunziata Filomena , Mjeshtri Anduela , Paudice Nunzia , Tsalouchos Aris , Zanazzi Maria , Bertoni Elisabetta
Published: January 2012

Warts are benign proliferations of the skin and mucosa caused by infection with human papillomavirus. They are commonly treated with destructive modalities such as cryotherapy with liquid nitrogen, local injection of bleomycin, electrocoagulation, topical application of glutaraldehyde, and local and systemic interferon-βtherapy. These treatment modalities often cause pain and sometimes scarring or pigmentation after treatment. We herein report a case with a right index finger wart, which was successfully treated with a topical activated vitamin D.
Microwave-Assisted Solution Phase Synthesis of Novel 2-{4-[2-(N-Methyl-2-pyridylamino)ethoxy]phenyl}-5-Substituted 1,3,4-Oxadiazole  Library
Authors: Gaonkar Santosh L. , Nagashima Izuru , Shimizu Hiroki
Published: January 2012

A new series of 2-{4-[2-(N-methyl-2-pyridylamino)ethoxy]phenyl}-5-substituted 1,3,4-oxadiazoles were synthesized by the oxidative cyclization of hydrazones derived from 4-[2-(methylpyridin-2-ylamino)ethoxy]benzaldehyde and aryl hydrazines using chloramine-T as an efficient catalyst. All steps were assisted by microwave irradiation. Microwave enables all these reactions to be simple, rapid, high yielding, and avoid chromatograph purification and led environmentally benign total synthesis of focused oxadiazole library. All the synthesized compounds were isolated in good yield and characterized by 1H NMR, 13C NMR, and elemental analyses. The title compounds represent a novel class of biologically active heterocycles.
Large Deviations for Stochastic Differential Equations on Sd Associated with the Critical Sobolev Brownian Vector Fields
Authors: Wang Qinghua
Published: January 2012

We obtain a large deviation principle for the stochastic differential equations on the sphere Sd associated with the critical Sobolev Brownian vector fields.