bluuebunny/crossref_metadata_2025 huggingface dataset:
Cesium radioisotope content of wild edible fungi, mineral soil, and surface litter in western North America after the Fukushima nuclear accident
Authors: Trappe Matthew J. , Minc Leah D. , Kittredge Kimberly S. , Pink Jeremias W.
Published: August 2014

We measured activity levels of radioisotopes cesium-134 (134Cs) and cesium-137 (137Cs) in wild edible fungi, mineral soil, and surface litter of the west coast of North America from southern California to northern Vancouver Island after the Fukushima nuclear accident. All activity measurements were below United States governmental limits for human health.137Cs activity increased to the north in mineral soils and fungal samples, whereas134Cs activity increased to the south in surface litter samples. Chanterelles (Cantharellus spp.) did not significantly bioconcentrate either radioisotope, but chanterelle activity levels were correlated with those of mineral soil. Activity levels demonstrated a high degree of variability, even in samples from the same site. In most cases, the level of137Cs activity was substantially higher than that of134Cs, suggesting that137Cs was present in the environment prior to the Fukushima release.
Existence of bounded solutions of integral boundary value problems for singular differential equations on whole lines
Authors: Liu Yuji , Chen Shengping
Published: August 2014

Boundary value problems of second-order singular differential equations with nonlinear operator Φ on whole lines are discussed. By applying the nonlinear alternative of Leray–Schauder-type fixed point theorem, some existence results of solutions for integral boundary value problems of differential equations on whole lines are established. The emphasis is put on the nonlinear operator [Φ(ρ(t)x′(t))]′ involved with the nonnegative function ρ that may satisfy ρ(0) = 0, the strictly increasing sup-multiplicative-like function Φ and the differential equations are defined on the whole line. Three examples and a remark are presented to illustrate the main theorems.
Effect of neutron flux, temperature and frequency on the permittivity of nanocrystalline silica
Authors: Huseynov Elchin , Garibov Adil , Mehdiyeva Ravan
Published: August 2014

In the work nano silica has been irradiated by 2×1013 cm -2 s -1 neutron flux at different times up to 20 h. The temperature and frequency dependencies of real and imaginary parts of dielectric constant of the nanomaterial exposed to neutron flux influence and initial state has been comparatively analyzed. From analysis results it has been revealed that the permittivity of nano SiO 2 increases in general tendency with influence of neutron flux. The mutual dependence of the real and imaginary parts of dielectric constant of nano SiO 2 particles has been reviewed. From the cases similar to Cole–Cole diagrams existing in the dependencies it has been revealed that the value of the relaxation period is compatible with polarization of the nano particles. It has been observed an increase in polarization with increase of influence period of neutron flux. Mechanisms of all effects observed in the experiments have been given.
Multifractal and singularity analysis of weighted road networks
Authors: Dai Meifeng , Zhang Cheng , Li Lei , Wu Wei
Published: August 2014

Road is an important element of modern traffic infrastructures in national economic construction. Accurately, road networks might be multifractal systems. The mathematics of multifractal can be used to provide a quantitative signature in many fields. The roads in this paper are endowed with weights according to their respective traffic abilities. With the aim in mind, the weighted road networks in three country-level cities (Danyang, Yangzhong and Jurong) which belong to Zhenjiang, China, are studied. We analyze the heterogeneities of the three weighted road networks with multifractal spectrum, which correspond to their socio-geographical contexts. Besides, we extract the singularity regions of three country-level cities with the annular segmentation method and the singularity exponent method, which can be helpful in further transportation planning.
Flow field of a unitary Fermi gas for the scissors mode
Authors: Lu Zhen-Bang , Chen Ji-Sheng , Li Jia-Rong
Published: August 2014

The scissors mode plays a crucial role in the study of the unitary Fermi gas. In this paper, we simulate the scissors mode by solving the hydrodynamic equations with appropriate initial conditions, and then extract the flow field of the gas. The flow fields in different regimes are found to be essentially different. The characteristic differences in the flow patterns between the superfluid and the normal viscous fluid are presented. Irrotational flow signals superfluidity, while rotational one indicates normal hydrodynamical behavior. These different characteristics can be visualized by the velocity portraits of the flow, which provide an intuitive way to discriminate the states of the Fermi gas.
Rn gravity is kicking and alive: The cases of Orion and NGC 3198
Authors: Salucci Paolo , Frigerio Martins Christiane , Karukes Ekaterina
Published: August 2014

We analyzed the Rotation Curves (RCs) of two crucial objects, the dwarf galaxy Orion and the low luminosity Spiral NGC 3198, in the framework of Rn gravity. We surprisingly found that the no dark matter (DM) power-law F(R) case fits them well, performing much better than LCDM halo models. The level of this unexpected success can be a boost for Rn gravity.
Calculation of inelastic electron–nucleus scattering form factors of29Si
Authors: Salman A. D. , Al-Dahan N. , Sharrad F. I. , Hossain I.
Published: August 2014

Inelastic electron scattering form factors for29Si nucleus with total angular momentum and positive parity (Jπ) and excited energy (3/2+, 1.273 MeV; 5/2+, 2.028 MeV; 3/2+, 2.425 MeV and 7/2+, 4.079 MeV) have been calculated using higher energy configurations outside the sd-shell. The calculations of inelastic form factors up to the first- and second-order with and without core-polarization (CP) effects were compared with the available experimental data. The calculations of inelastic electron scattering form factors up to the first-order with CP effects are in agreement with the experimental data, excepted for states 3/2+(1.273 MeV) and 5/2+(2.028 MeV) and without this effect are failed for all states. Furthermore, the calculations of inelastic electron scattering form factors up to the second-order with CP effects are in agreement with the experimental data for 3/2+(1.273 MeV) and 5/2+(2.028 MeV).
Nonminimal Dynamics of General Class k Tensegrity Systems
Authors: Cheong Joono , Skelton Robert E.
Published: August 2014

This paper addresses a unified formulation of dynamics of general class k(k = 1,2,…,) tensegrity systems using nonminimal coordinates in a matrix form. The dynamics are described by a matrix differential equation with a set of linear constraints, yielding a compact and simplified form. A reduced form of the dynamics is also provided by embedding the linear constraints to the full-order dynamics.
Active Flutter Control of a Supersonic Honeycomb Sandwich Beam Resting on Elastic Foundation with Piezoelectric Sensor/Actuator Pair
Authors: Nezami Mohammad , Gholami Behnam
Published: August 2014

In this paper, by using the piezoelectric material, the active aeroelastic flutter characteristics and vibration control of supersonic sandwich panels with different honeycomb interlayers, resting on an elastic foundation, are studied. Classical beam theory along with the Winkler–Pasternak foundation model, and the quasi-steady first order supersonic piston theory are employed in the formulation of the structural theory and aerodynamic loading, respectively. Hamilton's principle in conjunction with the generalized Fourier expansions and Rayleigh–Ritz (RR) method are used to develop the dynamical model of the structural systems in the state–space domain. The aeroelastic flutter bounds are obtained via the p-method. The classical Runge–Kutta integration algorithm is then used to calculate the open-loop aeroelastic response of the system under different loading excitations. Finally, two classical control strategies, including direct proportional feedback and linear-quadratic regulator (LQR) optimal control scheme, are used to actively suppress the closed loop system response, while increasing the flutter aerodynamic pressure.
Gutman index of product graphs
Authors: Paulraja P. , Sheeba Agnes V.
Published: August 2014

The exact value of the Gutman indices of the Cartesian product and the wreath product of graphs are obtained. Using the results obtained here, the exact Gutman indices of the hypercube, torus, grid, Hamming graph and the fence graph are given.
Toxicity Effect of Carbon Nanotubes
Authors: Zhao Zhuo , Liu Ming , Jia Xiaochuan , Wang Hua , Liu Zhipeng , Zhang Jie , Sun Li , Zhang Meng
Published: August 2014

Carbon nanotubes (CNT) have been known as one of the most important nanomaterials and their toxicological effects in vivo have been widely concerned. According to "Globally Harmonized System of classification and Labelling of Chemicals" (GHS) classification regulation, here, we analyzed the local toxicity (skin corrosion/irritation), acute oral toxicity, aquatic acute toxicity and reproductive toxicity of single-walled carbon nanotubes (SWCNTs) with the "Organization for Economic Co-operation and Development" (OECD) recommended chemical toxicity standard test methods. The experimental results showed that the LD50 and LC50 of SWCNT are all higher (LC50 more than 5000 mg/kg bw, LC50 more than 100 mg/L), but the skin irritation score is 0.6. As the standard of GHS, that means the SWCNT has no acute oral toxicity and aquatic acute toxicity, but it belongs to skin mild irritation substance. The investigations of reproductive toxicity showed that rate of cell micronuclei formation was significantly increased (p < 0.05) in 10.0 mg/kg dose group, and rate of mice sperm deformity was increased too (p < 0.05) in infected groups indicating that the SWCNT played a potentially role in reproductive toxicity.
Dense Plasma Focus: A question in search of answers, a technology in search of applications
Authors: Auluck S. K. H.
Published: August 2014

Diagnostic information accumulated over four decades of research suggests a directionality of toroidal motion for energetic ions responsible for fusion neutron production in the Dense Plasma Focus (DPF) and existence of an axial component of magnetic field even under conditions of azimuthal symmetry. This is at variance with the traditional view of Dense Plasma Focus as a purely irrotational compressive flow. The difficulty in understanding the experimental situation from a theoretical standpoint arises from polarity of the observed solenoidal state: three independent experiments confirm existence of a fixed polarity of the axial magnetic field or related azimuthal current. Since the equations governing plasma dynamics do not have a built-in direction, the fixed polarity must be related with initial conditions: the plasma dynamics must interact with an external physical vector in order to generate a solenoidal state of fixed polarity. Only four such external physical vectors can be identified: the earth's magnetic field, earth's angular momentum, direction of current flow and the direction of the plasma accelerator. How interaction of plasma dynamics with these fields can generate observed solenoidal state is a question still in search of answers; this paper outlines one possible answer. The importance of this question goes beyond scientific curiosity into technological uses of the energetic ions and the high-power-density plasma environment. However, commercial utilization of such technologies faces reliability concerns, which can be met only by first-principles integrated design of globally-optimized industrial-quality DPF hardware. Issues involved in the emergence of the Dense Plasma Focus as a technology platform for commercial applications in the not-too-distant future are discussed.
RF plasma polymerised thin films from natural resources
Authors: Jacob Mohan V. , Easton Chris D. , Anderson Liam J. , Bazaka Kateryna
Published: August 2014

Plasma polymerisation is an effective tool for fabrication of thin films from volatile organic monomers. RF plasma assisted deposition is used for one-step, chemical-free polymerisation of nonsynthetic materials derived directly from agricultural produces. By varying the deposition parameters, especially the input RF power, the film properties can be tailored for a range of uses, including electronics or biomedical applications. The fabricated thin films are optically transparent with refractive index close to that of glass. Given the diversity of essential oils, this paper compares the chemical and physical properties of thin films fabricated from several commercially exploited essential oils and their components. It is interesting to note that some of the properties can be tailored for various applications even though the chemical structure of the derived polymer is very similar. The obtained material properties also show that the synthesised materials are suitable as encapsulating layers for biodegradable implantable metals.
Current sheath formation in the plasma focus
Authors: Seng Y. S. , Lee P. , Rawat R. S.
Published: August 2014

The shaping and formation of the current sheath takes place in the breakdown phase of a plasma focus device. Achieving a clear understanding of the current sheath formation process is important because the plasma focus device performance depends on the quality of this sheath. In this paper, we created and successfully run an electromagnetic particle in cell code to simulate the breakdown phase. Magnetic effects are self-consistently incorporated in this formalism, allowing us to carry the simulation all the way to the point prior to breakdown.
A 160 kJ dual plasma focus (DuPF) for fusion-relevant materials testing and nano-materials fabrication
Authors: Saw S. H. , Damideh V. , Chong P. L. , Lee P. , Rawat R. S. , Lee S.
Published: August 2014

This paper summarizes PF-160 Dual Plasma Focus (DuPF) numerical experiments using the Lee Model code and preliminary 3D design drawings using SolidWorks software. This DuPF consists of two interchangeable electrodes enabling it to be optimized for both Slow Pinch Mode (SFM) and Fast Pinch Mode (FFM); the latter using a speed factor (SF) of 90 kA cm-1 Torr-0.5 for FFM in deuterium [S Lee et al, IEEE Trans Plasma Science 24, 1101-1105 (1996)]; and the former with SF of less than half that value for SFM. Starting with available 6 × 450 µF capacitors rated at 11kV (10% reversal), numerical experiments indicate safe operation at 9 kV, 6 Torr deuterium with FFM anode of 5 cm radius; producing intense ion beam and streaming plasma pulses which would be useful for studies of potential fusion reactor wall materials. On the other hand operating at 5 kV, 10 Torr deuterium with SFM anode of 10 cm radius leads to long-duration, uniform large-area flow which could be more suitable for synthesis of nano-materials. The dual plasma focus design is illustrated here with two figures showing FFM and SFM electrodes.
Design and construction of a very small repetitive plasma focus device
Authors: Goudarzi Shervin , Aral Nasrin , Babaee Hojat , Nasiri Ali , Esmaeli Abdolreza
Published: August 2014

In this paper the design and construction of a very Small Plasma Focus Device (20J) that can operate at repetition rate about 1 Hz are described. In the first experiments with it using Ar as working gas, high negative spikes in current derivative signals have seen, and the proper range of the operation using the Ar is identified.
EUV radiation from nitrogen capillary discharge
Authors: Frolov Oleksandr , Kolacek Karel , Schmidt Jiri , Straus Jaroslav
Published: August 2014

In the last decade EUV sources attract interest from researchers over the world. One of the main motivations is EUV lithography, which could lead to further miniaturization in electronics. Nitrogen recombination laser at wavelength of 13.4 nm based on capillary discharge Z-pinch configuration could be used in experiments with testing of resolution of photoresist for EUV lithography (close to wavelength of 13.5 nm Si/Mo multilayer mirrors have a high reflectivity at normal incidence angles).

In this work, pinching of nitrogen-filled capillary discharge is studied for the development of EUV laser, which is based on recombination pumping scheme. The goal of this study is achieving the required plasma conditions using a capillary discharge Z-pinch apparatus. In experiments with nitrogen, the capillary length was shortened from 232 mm to 90 mm and current quarter-period was changed from 60 ns to 50 ns in contrast with early experiments with Ne-like argon laser. EUV radiation from capillary discharge was registered by X-ray vacuum diode for different pressure, amplitude and duration of pre-pulse and charging voltage of the Marx generator.
The effect of limiter biasing on the plasma edge rotation and MHD activities
Authors: Lahazi A. , Khorshid P. , Ghoranneviss M.
Published: August 2014

Plasma edge rotations and magnetohydrodynamic behaviors have been studied during radial electric field variations in IR-T1 tokamak. An external positive limiter bias has been used as an external radial electric field. The profiles of radial electric field, floating potential, poloidal and toroidal rotation velocities and MHD activities have been studied during positive limiter bias. The poloidal and toroidal velocities reduced when the bias was applied and their fluctuations on the plasma edge became smoother furthermore. A significant excitation in dominant mode (4, 1) oscillation amplitude and a sharp decrease in magnetic island rotation frequency have been seen.
Design of a synchronization system for the “Gamma-4” electrophysical facility
Authors: Grishin A. V. , Glushkov S. L. , Mironychev B. P. , Kalashnikov D. A. , Kozachek A. V. , Martynov V. M. , Turutin V. V. , Sokolov V. V. , Kul'dushov D. A. , Nazarenko S. T. , Pavlov V. S. , Shikhanova T. F.
Published: August 2014

At RFNC-VNIIEF on the basis of a “Gamma-1” high-current pulsed accelerator there is being developed a four-module “Gamma-4” electrophysical facility. A synchronization system of the "Gamma-4" facility is meant for a simultaneous (with precision not worse than ±3 ns) triggering of high-volt gas-filled trigatron type switches of modules' pulse forming systems (144 items, operating voltage ≤ 1 MV), modules' pre-pulse switches (24 items, ≤ 3 MV) and 8 Marx generators (40 items, ≤ 100 kV). The synchronization system comprises 54 pulse generators, involving 25 generators on the basis of water insulated forming lines with distributed parameters and multi-channel gas-filled switches. On matched cable loads with resistances 0.45 Ohm these generators form voltage pulses with amplitudes 100 kV with durations 25 ns. A jitter of switches of these generators does not exceed ± 2 ns. To raise the amplitude of pulse drivers of pulse forming system switches and pre-pulse switches of modules in the facility synchronization system there are used step-up transformers based on pulsed high-voltage cables.
Preliminary numerical study of Thailand Plasma Focus II (TPF-II) design
Authors: Tamman Arlee , Nisoa Mudtorlep , Onjun Thawatchai
Published: August 2014

In this work, we use the Lee model to predict the plasma parameters, such as plasma temperature and pinch duration, in the 3.37 kJ DPF device, called “Thailand Plasma Focus-II (TPF-II).” This numerical result is then used to optimize the electrode parameters for the maximum production rate of 18F. The crossing point of pinch duration and pinch temperature is considered to obtain the appropriate electrode length, anode radius and gas gap between anode and cathode. The gas gap between both electrodes is indicated in ratio between cathode radius and anode radius, c. The results show that the best values of c, anode radius and electrode length are 1.48, 1.2 cm and 26.1 cm, respectively, in which the plasma pinch temperature, peak current and pinch duration of 0.76 keV, 207 kA and 8.725 ns can be obtained.
Time resolved tunable diode laser absoption spectroscopy of dual High Power Impulse Magnetron Sputtering discharges
Authors: Do Hoang Tung , Stranak Vitezslav , Hippler Rainer
Published: August 2014

Time-resolved measurements have been performed during dual High Power Impulse Magnetron Sputtering (dual-HiPIMS) with two cathodes in a closed magnetic field configuration. The dual-HiPIMS system, operated at a repetition frequency f = 100 Hz and duty cycle of 1 %, was equipped with two different metallic targets (Ti, Cu). The effect of a delay between subsequent pulses on argon excited atom density and temperature was investigated by means of tunable diode laser absorption spectroscopy. It is shown that the peak densities of pulses vary strongly with the delay. We observed an enhancement of metastable density due to pre-ionization effect but more effective than that is the contribution of metal atoms which have smaller ionization energy compare to that of buffer gas atom. Associate with the enhancement of density, the temporal variation of metastable atom temperature in the Cu pulse also transforms from those of low current pulse into the high current one.
The sine-law gap probability, Painlevé 5, and asymptotic expansion by the topological recursion
Authors: Marchal O. , Eynard B. , Bergère M.
Published: August 2014

The goal of this paper is to rederive the connection between the Painlevé 5 integrable system and the universal eigenvalues correlation functions of double-scaled Hermitian matrix models, through the topological recursion method. More specifically we prove, to all orders, that the WKB asymptotic expansions of the τ-function as well as of determinantal formulas arising from the Painlevé 5 Lax pair are identical to the large N double scaling asymptotic expansions of the partition function and correlation functions of any Hermitian matrix model around a regular point in the bulk. In other words, we rederive the "sine-law" universal bulk asymptotic of large random matrices and provide an alternative perturbative proof of universality in the bulk with only algebraic methods. Eventually we exhibit the first orders of the series expansion up to O(N-5).
Ranking Functions for Linear-Constraint Loops
Authors: Ben-Amram Amir M. , Genaim Samir
Published: August 2014

In this article, we study the complexity of the problems: given a loop, described by linear constraints over a finite set of variables, is there a linear or lexicographical-linear ranking function for this loop? While existence of such functions implies termination, these problems are not equivalent to termination. When the variables range over the rationals (or reals), it is known that both problems are PTIME decidable. However, when they range over the integers, whether for single-path or multipath loops, the complexity has not yet been determined. We show that both problems are coNP-complete. However, we point out some special cases of importance of PTIME complexity. We also present complete algorithms for synthesizing linear and lexicographical-linear ranking functions, both for the general case and the special PTIME cases. Moreover, in the rational setting, our algorithm for synthesizing lexicographical-linear ranking functions extends existing ones, because our definition for such functions is more general, yet it has PTIME complexity.
Rumpole
Authors: Marinovic Srdjan , Dulay Naranker , Sloman Morris
Published: August 2014

Access control policies define what resources can be accessed by which subjects and under which conditions. It is, however, often not possible to anticipate all subjects that should be permitted access and the conditions under which they should be permitted. For example, predicting and correctly encoding all emergency and exceptional situations is impractical. Traditional access control models simply deny all requests that are not permitted, and in doing so may cause unpredictable and unacceptable consequences. To overcome this issue, break-glass access control models permit a subject to override an access control denial if he accepts a set of obligatory actions and certain override conditions are met. Existing break-glass models are limited in how the override decision is specified. They either grant overrides for a predefined set of exceptional situations, or they grant unlimited overrides to selected subjects, and as such, they suffer from the difficulty of correctly encoding and predicting all override situations and permissions. To address this, we develop Rumpole, a novel break-glass language that explicitly represents and infers
knowledge gaps
and
knowledge conflicts
about the subject's attributes and the contextual conditions, such as emergencies. For example, a Rumpole policy can distinguish whether or not it is known that an emergency holds. This leads to a more informed decision for an override request, whereas current break-glass languages simply assume that there is no emergency if the evidence for it is missing. To formally define Rumpole, we construct a novel many-valued logic programming language called Beagle. It has a simple syntax similar to that of Datalog, and its semantics is an extension of Fitting's bilattice-based semantics for logic programs. Beagle is a knowledge non-monotonic langauge, and as such, is strictly more expressive than current many-valued logic programming languages.
Solving the Weighted Stable Set Problem in Claw-Free Graphs via Decomposition
Authors: Faenza Yuri , Oriolo Gianpaolo , Stauffer Gautier
Published: August 2014

We propose an algorithm for solving the maximum weighted stable set problem on claw-free graphs that runs in
O
(|
V
|(|
E
| + |
V
| log|
V
|))-time, drastically improving the previous best known complexity bound. This algorithm is based on a novel decomposition theorem for claw-free graphs, which is also introduced in the present article. Despite being weaker than the structural results for claw-free graphs given by Chudnovsky and Seymour [2005, 2008a, 2008b] our decomposition theorem is, on the other hand, algorithmic, that is, it is coupled with an
O
(|
V
||
E
|)-time algorithm that actually produces the decomposition.
Efficient Interactive Multiclass Learning from Binary Feedback
Authors: Ngo Hung , Luciw Matthew , Nagi Jawas , Forster Alexander , Schmidhuber Jürgen , Vien Ngo Anh
Published: August 2014

We introduce a novel algorithm called
upper
confidence
-
weighted
learning
(UCWL) for online multiclass learning from binary feedback (e.g., feedback that indicates whether the prediction was right or wrong). UCWL combines the upper confidence bound (UCB) framework with the soft confidence-weighted (SCW) online learning scheme. In UCB, each instance is classified using both score and uncertainty. For a given instance in the sequence, the algorithm might guess its class label primarily to reduce the class uncertainty. This is a form of informed exploration, which enables the performance to improve with lower sample complexity compared to the case without exploration. Combining UCB with SCW leads to the ability to deal well with noisy and nonseparable data, and state-of-the-art performance is achieved without increasing the computational cost. A potential application setting is human-robot interaction (HRI), where the robot is learning to classify some set of inputs while the human teaches it by providing only binary feedback—or sometimes even the wrong answer entirely. Experimental results in the HRI setting and with two benchmark datasets from other settings show that UCWL outperforms other state-of-the-art algorithms in the online binary feedback setting—and
surprisingly
even sometimes outperforms state-of-the-art algorithms that get full feedback (e.g., the true class label), whereas UCWL gets only binary feedback on the same data sequence.
A Logic for True Concurrency
Authors: Baldan Paolo , Crafa Silvia
Published: August 2014

We propose a logic for true concurrency whose formulae predicate about events in computations and their causal dependencies. The induced logical equivalence is hereditary history-preserving bisimilarity, and fragments of the logic can be identified which correspond to other true concurrent behavioural equivalences in the literature: step, pomset and history-preserving bisimilarity. Standard Hennessy-Milner logic, and thus (interleaving) bisimilarity, is also recovered as a fragment. We also propose an extension of the logic with fixpoint operators, thus allowing to describe causal and concurrency properties of infinite computations. This work contributes to a rational presentation of the true concurrent spectrum and to a deeper understanding of the relations between the involved behavioural equivalences.
A Framework for Expressing and Enforcing Purpose-Based Privacy Policies
Authors: Jafari Mohammad , Safavi-Naini Reihaneh , Fong Philip W. L. , Barker Ken
Published: August 2014

Purpose
is a key concept in privacy policies. Although some models have been proposed for enforcing
purpose-based privacy policies
, little has been done in defining formal semantics for purpose, and therefore an effective enforcement mechanism for such policies has remained a challenge. We have developed a framework for expressing and enforcing such policies by giving a formal definition of purpose and proposing a modal-logic language for formally expressing purpose constraints. The semantics of this language are defined over an abstract model of
workflows
. Based on this formal framework, we discuss some properties of purpose, show how common forms of purpose constraints can be formalized, how purpose-based constraints can be connected to more general access control policies, and how they can be enforced in a workflow-based information system by extending common access control technologies.
Comparing Vulnerability Severity and Exploits Using Case-Control Studies
Authors: Allodi Luca , Massacci Fabio
Published: August 2014

(U.S.) Rule-based policies for mitigating software risk suggest using the CVSS score to measure the risk of an individual vulnerability and act accordingly. A key issue is whether the ‘danger’ score does actually match the risk of exploitation in the wild, and if and how such a score could be improved. To address this question, we propose using a case-control study methodology similar to the procedure used to link lung cancer and smoking in the 1950s. A case-control study allows the researcher to draw conclusions on the relation between some
risk factor
(e.g., smoking) and an effect (e.g., cancer) by looking backward at the
cases
(e.g., patients) and comparing them with
controls
(e.g., randomly selected patients with similar characteristics). The methodology allows us to quantify the
risk reduction
achievable by acting on the risk factor. We illustrate the methodology by using publicly available data on vulnerabilities, exploits, and exploits in the wild to (1) evaluate the performances of the current risk factor in the industry, the CVSS base score; (2) determine whether it can be improved by considering additional factors such the existence of a proof-of-concept exploit, or of an exploit in the black markets. Our analysis reveals that (a) fixing a vulnerability just because it was assigned a high CVSS score is equivalent to randomly picking vulnerabilities to fix; (b) the existence of proof-of-concept exploits is a significantly better risk factor; (c) fixing in response to exploit presence in black markets yields the largest risk reduction.
Stable Analysis of Solution Set for System of Quasivariational Relations with Applications
Authors: Shi Lefeng , Yang Zhe
Published: August 2014

The essential stability of solutions for system of quasivariational relations is studied. We show that most of systems of quasivariational relations are essential (in the sense of Baire category) and that, for any system of quasivariational relations, there exists at least one essential component of its solution set. As applications, the existence of essential components of solution set for systems of KKM problems and systems of quasivariational inclusions is obtained.
Vibration Mitigation without Dissipative Devices: First Large-Scale Testing of a State Switched Inducer
Authors: Tirelli Daniel
Published: August 2014

A new passive device for mitigating cable vibrations is proposed and its efficiency is assessed on 45-meter long taut cables through a series of free and forced vibration tests. It consists of a unilateral spring attached perpendicularly to the cable near the anchorage. Because of its ability to change the cable dynamic behaviour through intermittent activation, the device has been called state switched inducer (SSI). The cable behaviour is shown to be deeply modified by the SSI: the forced vibration response is anharmonicc and substantially reduced in amplitude whereas the free vibration decay is largely sped up through a beating phenomenon. The vibration mitigation effect is mainly due to the activation and coupling of various vibration modes, as evidenced in the response spectra of the equipped cable. This first large-scale experimental campaign shows that the SSI outperforms classical passive devices, thus paving the way to a new kind of low-cost vibration mitigation systems which do not rely on dissipation.
Flash‐Aware Page Replacement Algorithm
Authors: Xu Guangxia , Ren Lingling , Liu Yanbing
Published: August 2014

Due to the limited main memory resource of consumer electronics equipped with NAND flash memory as storage device, an efficient page replacement algorithm called FAPRA is proposed for NAND flash memory in the light of its inherent characteristics. FAPRA introduces an efficient victim page selection scheme taking into account the benefit‐to‐cost ratio for evicting each victim page candidate and the combined recency and frequency value, as well as the erase count of the block to which each page belongs. Since the dirty victim page often contains clean data that exist in both the main memory and the NAND flash memory based storage device, FAPRA only writes the dirty data within the victim page back to the NAND flash memory based storage device in order to reduce the redundant write operations. We conduct a series of trace‐driven simulations and experimental results show that our proposed FAPRA algorithm outperforms the state‐of‐the‐art algorithms in terms of page hit ratio, the number of write operations, runtime, and the degree of wear leveling.
Designing Fault Tolerance Strategy by Iterative Redundancy for Component‐Based Distributed Computing Systems
Authors: Wang Hui , Wang Yun
Published: August 2014

Reliability is a critical issue for component‐based distributed computing systems, some distributed software allows the existence of large numbers of potentially faulty components on an open network. Faults are inevitable in this large‐scale, complex, distributed components setting, which may include a lot of untrustworthy parts. How to provide highly reliable component‐based distributed systems is a challenging problem and a critical research. Generally, redundancy and replication are utilized to realize the goal of fault tolerance. In this paper, we propose a CFI (critical fault iterative) redundancy technique, by which the efficiency can be guaranteed to make use of resources (e.g., computation and storage) and to create fault‐tolerance applications. When operating in an environment with unknown components’ reliability, CFI redundancy is more efficient and adaptive than other techniques (e.g., K‐Modular Redundancy and N‐Version Programming). In the CFI strategy of redundancy, the function invocation relationships and invocation frequencies are employed to rank the functions’ importance and identify the most vulnerable function implemented via functionally equivalent components. A tradeoff has to be made between efficiency and reliability. In this paper, a formal theoretical analysis and an experimental analysis are presented. Compared with the existing methods, the reliability of components‐based distributed system can be greatly improved by tolerating a small part of significant components.
Existence and Uniqueness of Globally Attractive Positive Almost Periodic Solution in a Predator-Prey Dynamic System with Beddington-DeAngelis Functional Response
Authors: Wu Wenquan
Published: August 2014

This paper is concerned with a predator-prey system with Beddington-DeAngelis functional response on time scales. By using the theory of exponential dichotomy on time scales and fixed point theory based on monotone operator, some simple conditions are obtained for the existence of at least one positive (almost) periodic solution of the above system. Further, by means of Lyapunov functional, the global attractivity of the almost periodic solution for the above continuous system is also investigated. The main results in this paper extend, complement, and improve the previously known result. And some examples are given to illustrate the feasibility and effectiveness of the main results.
Numerical Investigation on Jet Impingement Behaviors Affected by a Vertically Rotating Disk Suspended Close to the Surface
Authors: Bo Liu , Jing-zhou Zhang , Xiao-ming Tan
Published: August 2014

A simplified physical model is built up to study the swirl flow effect induced by a rotating disk on the jet impingement behaviors, which is adopted to simulate the grinding process. To solve the definition problem of the interface between a rotating disk and a stationary plate in the computational simulation, a tiny gap is set between the rotating disk and the stationary plate. The results show that the rotating disk suspended above the surface adds more complexity to the flow field of jet impingement on a stationary plate. The swirling flow around the rotating disk obstructs the impinging jet flow to penetrate into the interfacial contact zone and forces the wall jet across the rotating disk to flow along transverse directions. For the given jet impinging velocity and nozzle orientation, as the disk rotational speed increases, the effect of the rotating disk on the impinging jet flow behaves more significantly. The impinging jet with small inject velocity is difficult to penetrate through the interfacial contact zone to follow by the disk swirl flows. For smaller jet impinging distance or larger oblique angle, the flow recirculation away from the interfacial contact zone becomes stronger.
A Traction Control Strategy with an Efficiency Model in a Distributed Driving Electric Vehicle
Authors: Lin Cheng , Cheng Xingqun
Published: August 2014

Both active safety and fuel economy are important issues for vehicles. This paper focuses on a traction control strategy with an efficiency model in a distributed driving electric vehicle. In emergency situation, a sliding mode control algorithm was employed to achieve antislip control through keeping the wheels’ slip ratios below 20%. For general longitudinal driving cases, an efficiency model aiming at improving the fuel economy was built through an offline optimization stream within the two-dimensional design space composed of the acceleration pedal signal and the vehicle speed. The sliding mode control strategy for the joint roads and the efficiency model for the typical drive cycles were simulated. Simulation results show that the proposed driving control approach has the potential to apply to different road surfaces. It keeps the wheels’ slip ratios within the stable zone and improves the fuel economy on the premise of tracking the driver’s intention.
Krüppel-Like Factor 5 Mediates Proinflammatory Cytokine Expression in Lipopolysaccharide-Induced Acute Lung Injury through Upregulation of Nuclear Factor-κB PhosphorylationIn VitroandIn Vivo
Authors: Chen Hsiu-Lin , Chong Inn-Wen , Lee Yi-Chen , Tsai Jong-Rung , Yuan Shyng-Shiou F. , Wang Hui-Min , Liu Wei-Lun , Liu Po-Len
Published: August 2014

Acute lung injury (ALI) is associated with an inflammation-mediated process, and the transcription factor, Krüppel-like factor 5 (KLF5), might play a crucial role in inflammatory lung disease. In this study, we evaluated KLF5, reactive oxygen species (ROS), and inflammatory responses in a lipopolysaccharide- (LPS-) induced ALI model to elucidate the role of KLF5 in ALI. Our data indicated that LPS upregulates proinflammatory cytokine expression in human bronchial epithelial cells in a dose-dependent manner. We observed upregulated KLF5 protein expression in human bronchial epithelial cells exposed to LPS, with peak expression 1 h after LPS treatment, and subsequent upregulation of p65 protein expression and p65 phosphorylation at Ser276. These results indicate that KLF5 mediates proinflammatory cytokine expression by upregulating nuclear factor-kappaB (NF-κB) phosphorylation at p65 in response to LPS. LPS treatment also increased ROS production and simultaneously upregulated KLF5 expression and NF-κB translocation. N-acetylcysteine significantly reduced ROS levels and KLF5 and NF-κB translocation in nuclear extracts. Therefore, N-acetylcysteine pretreatment before LPS exposure reduces ROS, downregulates KLF5 expression, and subsequently reduces inflammatory responses by scavenging ROS. Overall, our study results indicate that KLF5 mediates proinflammatory cytokine expression through upregulation of NF-κB phosphorylation at p65 in LPS-induced ALI.
Parking Backbone: Toward Efficient Overlay Routing in VANETs
Authors: Zhu Jinqi , Liu Ming , Wen Yonggang , Ma Chunmei , Liu Bin
Published: August 2014

In vehicular ad hoc networks (VANETs), message dissemination to one or more vehicles is very challenging, due to frequent network disconnections and uncertain locations of the destination vehicles. Deploying roadside units (RSUs) is a possible solution to overcome the challenges, but it often requires a large amount of investment. In this paper, we propose the idea of Parking Backbone, which does not need any RSUs but leverages a virtual overlay network formed by outside parked vehicles to track vehicles and to disseminate messages between moving vehicles. Our scheme consists of three parts. At first, to each road, parked vehicles both at roadside and off street are grouped into a cluster as far as possible. An urban overlay network is established based on this type of clusters for data transmission. Secondly, to a specific vehicle, a daily mobility model is established, to determine its location through a corresponding location prediction algorithm. Finally, a novel message delivery scheme is designed to efficiently transmit messages to destination vehicles through the proposed virtual overlay network. Thanks to the extensive and stable outside parking in cities, once grouped into the overlay structure, data transmission can be easily achieved over the Parking Backbone. Extensive simulation results prove that our scheme achieves high performance in message dissemination.
A Novel Fractional‐Order PID Controller for Integrated Pressurized Water Reactor Based on Wavelet Kernel Neural Network Algorithm
Authors: Zhao Yu-xin , Du Xue , Xia Geng-lei
Published: August 2014

This paper presents a novel wavelet kernel neural network (WKNN) with wavelet kernel function. It is applicable in online learning with adaptive parameters and is applied on parameters tuning of fractional‐order PID (FOPID) controller, which could handle time delay problem of the complex control system. Combining the wavelet function and the kernel function, the wavelet kernel function is adopted and validated the availability for neural network. Compared to the conservative wavelet neural network, the most innovative character of the WKNN is its rapid convergence and high precision in parameters updating process. Furthermore, the integrated pressurized water reactor (IPWR) system is established by RELAP5, and a novel control strategy combining WKNN and fuzzy logic rule is proposed for shortening controlling time and utilizing the experiential knowledge sufficiently. Finally, experiment results verify that the control strategy and controller proposed have the practicability and reliability in actual complicated system.
Total Anomalous Systemic Venous Drainage with Heterotaxia Syndrome: A Rare Case
Authors: Yildirim Ali , Kosger Pelin , Ozdemir Gokmen , Ucar Birsen , Kilic Zubeyir
Published: August 2014

Total anomalous systemic venous return is a very rare anomaly, where vena cava inferior, vena cava superior, and coronary sinus drain into left atrium. Two-day-old male baby was admitted with cyanosis and tachypnea after the birth. Left atrial isomerism with anomalous systemic venous drainage was found on echocardiographic examination. We present an unusual case of total anomalous systemic venous drainage in to the left atrium.
Numerical Simulation of Sloshing in 2D Rectangular Tanks Based on the Prediction of Free Surface
Authors: Zhang Haitao , Sun Beibei
Published: August 2014

A finite difference method for analyzing 2D nonlinear sloshing waves in a tank has been developed based on the potential flow theory. After σ‐transformation, the free surface is predicted by the kinematic condition, and nonlinear terms are approximated; the governing equation and boundary conditions are discretized to linear equations in the iterative process of time. Simulations of standing waves and sloshing in horizontally excited tanks are presented. The results are compared with analytical and numerical solutions in other literatures, which demonstrate the effectiveness and accuracy of this numerical method. The beating phenomenon of sloshing in the tank with different aspect ratios is studied. The relationship between sloshing force and aspect ratio under the same external excitation is also discussed.
Antifungal and Antioxidant Activities of the Essential Oil from Angelica koreana Nakai
Authors: Roh Junghyun , Shin Seungwon
Published: August 2014

Purpose. The purpose of this study is to determine the antifungal and antioxidant activities of the essential oil from Angelica koreana. Methods. Essential oil was obtained from the dried roots of A. koreana by steam distillation, and its composition was identified by gas chromatography and mass spectrometry (GC‐MS). The minimal inhibitory concentrations (MICs) of the oil fraction and its main components were determined by broth dilution assay using common pathogenic Aspergillus and Trichophyton species. The combined effects of the oils with itraconazole were evaluated using a checkerboard titer test. In addition, 1,1‐diphenyl‐2‐picryl‐hydrazil (DPPH) free radical scavenging, nitrite inhibition, and reducing power were determined to assess the antioxidant activity of this oil. Results. The essential oil fraction and its main components showed inhibitory activity against all of the tested fungi, with minimal inhibitory concentrations (MICs) of 250–1000 μg/mL. Furthermore, this oil exhibited synergism when combined with itraconazole. Conclusion. In the treatment of infections caused by Aspergillus and Trichophyton species, combining itraconazole with either A. koreana essential oil or its main components may reduce the minimum effective dose of itraconazole required and, thus, minimize its side effects. In addition, this oil is a promising source of natural antioxidant agents.
Geographical Variation in Morphological and Bioacoustic Traits ofPseudopaludicola mystacalis(Cope, 1887) and a Reassessment of the Taxonomic Status ofPseudopaludicola serranaToledo, 2010 (Anura: Leptodactylidae: Leiuperinae)
Authors: Pansonato André , Rhaiza Mudrek Jessica , Simioni Fernanda , Alves Martins Itamar , Strüssmann Christine
Published: August 2014

Comparisons of advertisement calls of anurans can be used to determine intra- and interspecific differences or affinities. Described from midwestern Brazil,Pseudopaludicola mystacalisis widely distributed and abundant in major open Brazilian ecosystems. However, researchers frequently fail to determine the true taxonomic status of some of these populations and attribute them to unidentified or misidentified species. Herein, we employ morphological and bioacoustic data to reassess the distribution range and to evaluate intraspecific variation inP. mystacalisbased on specimens from fifteen localities and seven Brazilian states. We also reassess the distribution and taxonomic status ofPseudopaludicola serrana, herein considered as a junior synonym ofP. murundubased on morphology, bioacoustics, and molecular data.