bluuebunny/crossref_metadata_2025 huggingface dataset:
Analytical Modeling and FE Simulation for Analyzing Applied Forces During Roll Bending Process
Authors: Tran Hoang Quan , Champliaud Henri , Feng Zhengkun , Dao Thien-My
Published: September 2013

High strength steel is widely used in the manufacturing of parts dealing with heavy cyclic loads and corrosive environments. However, processing this type of steel is not easy, and it becomes a hard-to-solve problem when the part to produce is large, thick and quasi-unique. One example of a thick high strength steel axisymmetric part is the conical shape of the crown of a Francis turbine runner. Some Francis turbine runners installed in the dam basement of a hydraulic power plant are 10 meters in diameter with more than 5 meters in height, while plate thickness can exceed 100 millimeters. Several processes can be envisaged for the manufacturing processes of such large parts (welding or casting…), but few processes can deliver one within a reasonable time and at competitive cost. Among them the roll bending process, causing plastic deformation of a plate around a linear axis with little or no change in plate thickness, is considered as an interesting alternative.

The main objective of this research is to assess 3D dynamic finite element and analytical models for the computation of the bending forces during the manufacturing of hollow conical parts made of a thick plate and a high strength steel. Numerous parameters such as thickness, curvature, part size, material properties and friction directly influence the reaction forces on the rolls. Therefore, the results of this research provide a better understanding of the phenomena taking place in the process, and an opportunity to establish relationships between the bending forces and the parameters of a final conical part.
Topology Optimization of Structures Using a Global Stress Measure
Authors: Yalamanchili Vijay Krishna , Kumar Ashok V.
Published: September 2013

An approach for stress based topology optimization is studied here where stress constraints for continuum structures are imposed using a conservative global stress measure. A relation between the mean compliance and Von-Mises stress is used to construct an objective function that minimizes mass until stress constraints are activated. This approach is implemented in a mesh independent finite element framework where the feasible region is defined using boundary equations while analysis and topology optimization are performed on a background mesh. The SIMP approach is used for topology optimization and nodal values of density are treated as the design variables. The density field is interpolated over the elements to obtain a continuous distribution. To ensure smooth boundaries a smoothing term is also added to the objective function which minimizes gradient of the density function. The optimization problem is then solved using Moving Barrier Method (MBM). Several examples are studied to evaluate this approach.
Unstable Vibrations of a Wind Turbine Tower With Two Blades
Authors: Ikeda Takashi , Harata Yuji , Ishida Yukio
Published: September 2013

Unstable vibrations of a two-blade wind turbine tower are theoretically investigated. The theoretical model is a five-degree-of-freedom (5DOF) system, however, the equations of motion are derived separately for 3DOF subsystem (I) and 2DOF subsystem (II). Parametric excitation due to the asymmetry of the moments of inertia of the blade rotor is included only in subsystem (I). Frequency equations are derived and natural frequency diagrams are calculated to clearly demonstrate both the rotational speeds where unstable regions appear and which type of unstable vibrations may occur. It is found that at most, five unstable regions may appear depending on the values of the system parameters in subsystem (I). Two types of unstable vibrations may occur; single mode including a single frequency and dual mode including two frequencies. The influences of the asymmetry of moments of inertia, tower rigidity, and installation position of the blade rotor on the response of the system are also theoretically investigated. Van der Pol’s method is applied to determine the expressions for the response curves. The influences of the blade rotor unbalances on the translational, inclinational and torsional vibrations of the tower are shown. It is found that the amplitudes of the response curves corresponding to single and dual mode are infinite and finite at their boundaries, respectively. The validity of the theoretical analysis is confirmed by numerical simulations.
Measurement of the tangential momentum accommodation coefficient of H2 on stainless steel, extreme ultraviolet-resist, and polyimide
Authors: Velthuis Johannes F. M. , van Bokhoven Laurens
Published: September 2013

The tangential momentum accommodation coefficient (TMAC) of H2 on electropolished stainless steel 304, extreme ultraviolet-resist, and polyimide was determined by measuring the mass flow through a macroscopic rectangular channel (100 cm × 10 cm × 1 cm) as a function of the pressure drop in the Knudsen range Knave ≈ 0–0.6. The TMAC and Knudsen number determine the amount of velocity slip taking place at the wall at rarefied conditions. By comparing the measurements with an analytical expression for the mass flow through the channel, including the 1st order slip flow contribution to continuum, the only remaining unknown, that is, the TMAC, was extracted.
Pseudo-homophony in non-native listening
Authors: Cutler Anne , Otake Takashi
Published: September 2013

Pseudo-homophony may result when non-native listeners cannot distinguish phonemic contrasts. Thus Dutch listeners have difficulty distinguishing the vowels of English cattle versus kettle, because this contrast is subsumed by a single Dutch vowel category; in consequence, both words may be activated whenever either is heard. A lexical decision study in English explored this phenomenon by testing for repetition priming. The materials contained among 340 items 18 pairs such as cattle/kettle, i.e., contrasting only in those vowels, and 18 pairs contrasting only in r/l (e.g., right/light). These materials, spoken by a native American English speaker, were presented to fluent non-native speakers of English, 48 Dutch Nijmegen University students, and 48 Japanese Dokkyo University students; the listeners performed lexical decision on each spoken item, and response time was measured. Dutch listeners responded significantly faster to one member of a cattle/kettle pair after having heard the other member earlier in the list (compared with having heard a control word), suggesting that both words had been activated whichever had been heard. Japanese listeners, however, showed no such priming for cattle/kettle words, but did show repetition priming across r/l pairs such as right/light. Non-native listeners’ phonemic discrimination difficulties thus generate pseudo-homophony.
Evaluation of an ultrasonic displacement sensor
Authors: Fenneman Douglas , Libbey Bradley , Martin James
Published: September 2013

An ultrasonic displacement sensor is currently being investigated. A possible application for this sensor is acoustic/seismic landmine detection in which a noncontact vibrometer is employed to measure the normal surface velocity of soil. The ultrasonic sensor is an alternative displacement sensor to a laser Doppler vibrometer (LDV). The ultrasonic wavelength suggests that the ultrasonic sensor is capable of resolving displacements in the presence of rough surfaces. This functionality is of particular interest because scattering of optical signals by rough surfaces can prohibit accurate LDV measurements. The ultrasonic sensor will be evaluated in an array of surface roughness conditions. The performance of the ultrasonic sensor will be compared to the LDV for each of these cases. The relative advantages and limitations of the ultrasound system will be presented. The applicability of the ultrasonic sensor to acoustic mine detection will also be addressed.
Apfel’s superheated drop detector
Authors: d’Errico Francesco
Published: September 2013

The introduction of new approaches for radiation dosimetry is rare. A similar breakthrough occurred in 1979, when Robert Apfel invented the superheated drop detector, a miniature relative of the bubble chamber. A fundamental in high-energy particle physics, the bubble chamber utilizes a liquid briefly brought to a transient, radiation-sensitive superheated state by reducing its pressure. Mass boiling of the liquid is prevented by cyclic pressurization, drastically limiting the detection efficiency. In Apfel’s detector, the liquid is kept in a steady superheated state by fractionating it into droplets and dispersing them in an immiscible host fluid, a perfectly smooth and clean container. The approach extends the lifetime of the metastable droplets to the point that practical application in radiation dosimetry is possible. Bubble formation is measured from the volume of vapor or by detecting individual vaporizations acoustically. Various halocarbons are employed and this permits a wide range of applications. Moderately superheated halocarbons are used for neutron measurements, since they are only nucleated by energetic neutron recoil particles. Highly superheated halocarbons nucleate with much smaller energy deposition and are used to detect photons and electrons. This paper reviews the radiation physics of superheated emulsions and their manifold applications.
A new 3D dynamical biomechanical tongue model
Authors: Gerard Jean-Michel , Perrier Pascal , Payan Yohan , Wilhelms-Tricarico Reiner
Published: September 2013

A new dynamical biomechanical tongue model is being developed to study speech motor control. In spite of its computational complexity, a 3D representation was chosen in order to account for various contacts between tongue and external structures such as teeth, palate, and vocal tract walls. A fair representation of tongue muscle anatomy is provided, by designing the finite element mesh from the visible human data set (female subject). Model geometry was then matched to a human speaker, so that simulations can be quantitatively compared to experimental MRI data. A set of 11 muscles is modeled, whose role in speech gestures is well established. Each muscle is defined by a set of elements whose elastic properties change with muscle activation. Muscles forces are applied to the tongue model via macrofibers defined within the mesh by muscle specific sets of nodes. These forces are currently specified as step functions. Boundary conditions are set using zero-displacement nodes simulating attachments of tongue on bony structures. The nonlinear mechanical properties of tongue soft tissues are modeled using a hyperelastic material. Three-dimensional tongue deformations generated by each muscle, using FEM software ANSYS for computation, will be presented. Implications for speech motor control will be proposed.
Vocalization of Equus asinus: The hees and haws of donkey brays
Authors: Browning David G. , Scheifele Peter M.
Published: September 2013

An understanding of the vocalizations of farm animals may provide an important key in the identification of animals under stress. Donkey vocalizations (brays) appear to be unique among the Equidae in that significant sound is produced during both air intake (the hee) and air outflow (the haw). Typically these vocalizations, primarily by males, consist of a series of brays, seemingly mechanically produced with little variation, terminating when the animal becomes short of breath—literally a burst of sound. The acoustic character, duration, and sequence (some hee-haw, while others haw-hee) are unique to each animal. As with other Perissodactyles (horses, zebras), and in contrast to the Artiodactyls (cows, sheep, and goats), there can be a significant frequency variation during a vocalization segment (particularly in the ‘‘haw’’ phase). It has not been determined what control (if any) the animal has over this. Further study is being made of possible braying variations for a given animal.
Reconstruction of mechanically recorded sound by image processing
Authors: Fedeyev Vitaliy , Haber Carl , Radding Zachary , Maul Christian , McBride John , Golden Mitchell
Published: September 2013

Audio information stored in the undulations of grooves in a medium such as a phonograph record or cylinder may be reconstructed, without contact, by measuring the groove shape using precision optical metrology methods and digital image processing. In this approach, audio signal processing is accomplished by two- or three-dimensional image analysis and processing. The viability of these methods was recently demonstrated on a 78 rpm shellac disc using two-dimensional image acquisition and analysis methods [V. Fadeyev and C. Haber, J. Audio Eng. Soc. 51(12), 1172–1185 (2003)]. The present work expands on these results. A three-dimensional reconstruction of mechanically recorded sound is reported. The source material, an Edison cylinder, was scanned using confocal microscopy and resulted in a faithful playback of the recorded information. Methods to accelerate the scan rates and make these techniques practical for use in working archives are reported as well. [Work supported by the Laboratory Technology Research Program (SC-32), within the Office of Science, U.S. Department of Energy under Contract No. DE-AC03-76SF00098.]
Assessment of material fatigue damage using nonlinear vibro-modulation technique
Authors: Zagrai Andrei , Donskoy Dimitri , Chudnovsky Alexander , Wu Hudson
Published: September 2013

Heavy periodic loads exerted on structural materials often lead to fatigue damage (material degradation at microscale) which may finally trigger irreversible fracture process. Conventional NDT techniques detect only the latter, and there is an increasing need for new tools to assess fatigue damage at the earliest possible stage, i.e., before fracture. This paper presents experimental results of early damage characterization using an innovative nonlinear vibro-modulation technique (VMT) [Donskoy et al., NDT&E Int. 34 (2001)]. In the experiments, fatigue damage was initiated in steel, aluminum, and carbon–carbon composite specimens during strain-controlled three-point bending high-cycling fatigue tests. The damage progress was independently monitored using dataflow from the testing machine and the real-time nonlinear vibro-modulation measurements. The tests demonstrated that the reduction in the specimens’ stiffness (direct indication of damage accumulation) correlates well with the increase in the VMT’s nonlinear damage index. These results confirm that VMT could offer new opportunities for early damage detection and remaining life prediction. [Work supported by NAVAIR.]
Model-based broadband towed-array processing
Authors: Sullivan Edmund J. , Edelson Geoffrey S.
Published: September 2013

Conventional broadband towed array processors operate in the frequency domain and exploit the phases of the frequency components from a DFT to extract the bearing estimate. In this process, the fact that the array is moving is not taken into consideration. In fact, to first order, the effect of the motion is negligible. However, it has been shown that, in the narrow-band case, the effect of the motion on the variance of the bearing estimate is not negligible. This is due to the fact that the Doppler incurred by the motion itself carries bearing information. In this work, it is shown that a recursive bearing estimation scheme, based on sequential DFT’s, can produce the so-called synthetic aperture effect, where the Cramer–Rao lower bound on the bearing estimate progressively decreases, as compared to the case where the motion is not explicitly included in the processing scheme. Examples of this effect are shown based on simulated data, and the capabilities and limitations of the technique are discussed.
Dolphin sonar detection and discrimination capabilities
Authors: Au Whitlow W. L.
Published: September 2013

Dolphins have a very sophisticated short range sonar that surpasses all technological sonar in its capabilities to perform complex target discrimination and recognition tasks. The system that the U.S. Navy has for detecting mines buried under ocean sediment is one that uses Atlantic bottlenose dolphins. However, close examination of the dolphin sonar system will reveal that the dolphin acoustic hardware is fairly ordinary and not very special. The transmitted signals have peak-to-peak amplitudes as high as 225–228 dB re 1 μPa which translates to an rms value of approximately 210–213 dB. The transmit beamwidth is fairly broad at about 10o in both the horizontal and vertical planes and the receiving beamwidth is slightly broader by several degrees. The auditory filters are not very narrow with Q values of about 8.4. Despite these fairly ordinary features of the acoustic system, these animals still demonstrate very unusual and astonishing capabilities. Some of the capabilities of the dolphin sonar system will be presented and the reasons for their keen sonar capabilities will be discussed. Important features of their sonar include the broadband clicklike signals used, adaptive sonar search capabilities and large dynamic range of its auditory system.
Bluefin autonomous underwater vehicles: Programs, systems, and acoustic issues
Authors: Bondaryk Joseph E.
Published: September 2013

Bluefin Robotics Corporation has been manufacturing autonomous underwater vehicles (AUVs) since spinning out of the MIT Sea Grant Laboratory in 1997. Bluefin currently makes three different diameter models of AUVs; the 9, 12, and 21, all based on the same free-flooded architecture and vectored-thrust propulsion design. Auxiliary acoustic systems include acoustic abort, ranging beacons, and acoustic modems. Vehicle navigation is aided by a downward-looking acoustic Doppler velocity logger (DVL). Sonar payloads can include: bottom profiler, side-scan sonar, SAS, forward-looking imagers (DIDSON), as well as horizontal and vertical discrete hydrophone arrays. Acoustic issues that arise include: (1) transmission of sound through the ABS plastic vehicle shell; (2) the impact of vehicle self-noise on data; (3) interoperability of sonars with other acoustic emitters present on and off the vehicle; and (4) the impact of navigation on some acoustic operations like SAS. This talk will illustrate these issues with real data collected on various Bluefin vehicles.
AUV-based synthetic aperture sonar: Initial experiences and insights
Authors: Cook Daniel A. , Fernandez Jose E. , Stroud John S. , Commander Kerry W. , Matthews Anthony D.
Published: September 2013

The ability to do synthetic aperture sonar (SAS) imaging from autonomous underwater vehicles (AUVs) has only recently been achieved. The combination of the two technologies is a milestone in the field of underwater sensing as the combination of high-resolution SAS imaging with AUVs will provide military, research, and commercial users with systems of unprecedented performance and capabilities. The U.S. Navy took delivery of the first AUV-based SAS in early 2003. A description of the system will be presented along with the methodologies employed. The emphasis will be on image quality and repeatability, as well as the differences associated with operating an AUV-based SAS as opposed to a towed SAS. Additional topics will include general comments and recommendations for better AUV/SAS integration such as mission planning and vehicle control strategies intended to maximize the chances of high-quality imagery, SAS motion measurement requirements coupled with on-board vehicle navigation, and the potential of using the SAS data to augment the vehicle motion sensors. Lastly, a brief overview of forthcoming Navy SAS systems will be included.
Horizontal coherence in the NPAL experiment
Authors: Vera Michael , Dzieciuch Matthew
Published: September 2013

Acoustic transmissions from a broadband source near Kauai with a center frequency of 75 Hz were recorded on a two-dimensional receiver array at a range of 3900 km as part of the North Pacific Acoustic Laboratory (NPAL) experiment. The receiver array consisted of five vertical line arrays (VLAs), with separations transverse to the propagation path ranging from a few hundred meters to a few kilometers. The coherences derived from the data have been compared to two different numerical predictions based on sound-speed perturbations due to internal waves. An approximation to the acoustic path integral yields a prediction for the length scale of horizontal coherence. Parabolic-equation simulations of propagation from the source to each VLA through multiple realizations of a random internal-wave field provide another estimate of the coherence at each horizontal separation. [Work supported by ONR.] a)J. A. Colosi, B. D. Cornuelle, B. D. Dushaw, M. A. Dzieciuch, B. M. Howe, J. A. Mercer, R. C. Spindel, and P. F. Worcester.
The meaning of city noises: Investigating sound quality in Paris (France)
Authors: Dubois Daniele , Guastavino Catherine , Maffiolo Valerie , Guastavino Catherine , Maffiolo Valerie
Published: September 2013

The sound quality of Paris (France) was investigated by using field inquiries in actual environments (open questionnaires) and using recordings under laboratory conditions (free-sorting tasks). Cognitive categories of soundscapes were inferred by means of psycholinguistic analyses of verbal data and of mathematical analyses of similarity judgments. Results show that auditory judgments mainly rely on source identification. The appraisal of urban noise therefore depends on the qualitative evaluation of noise sources. The salience of human sounds in public spaces has been demonstrated, in relation to pleasantness judgments: soundscapes with human presence tend to be perceived as more pleasant than soundscapes consisting solely of mechanical sounds. Furthermore, human sounds are qualitatively processed as indicators of human outdoor activities, such as open markets, pedestrian areas, and sidewalk cafe districts that reflect city life. In contrast, mechanical noises (mainly traffic noise) are commonly described in terms of physical properties (temporal structure, intensity) of a permanent background noise that also characterizes urban areas. This connotes considering both quantitative and qualitative descriptions to account for the diversity of cognitive interpretations of urban soundscapes, since subjective evaluations depend both on the meaning attributed to noise sources and on inherent properties of the acoustic signal.
Temporal loudness weights for sounds with increasing and decreasing intensity profiles
Authors: Ponsot Emmanuel , Susini Patrick , Saint Pierre Guillaume , Meunier Sabine
Published: September 2013

Using molecular psychophysics, temporal loudness weights were measured for 2-s, 1-kHz tones with flat, increasing and decreasing time-intensity profiles. While primacy and recency effects were observed for flat profile stimuli, the so-called “level dominance” effect was observed for both increasing and decreasing profile stimuli, fully determining their temporal weights. The weighs obtained for these profiles were basically zero for all but the most intense parts of these sounds. This supports the view that the “level dominance” effect is prominent with intensity-varying sounds and that it persists over time since temporal weights are not affected by the direction of intensity change.
Recognising avian notifiable diseases 1. Avian influenza
Authors: Irvine Richard M.
Published: September 2013

The avian notifiable diseases avian influenza and Newcastle disease are two of the most feared livestock diseases, both being highly infectious transboundary viral diseases that can affect domestic poultry and wild and captive birds. As a result, both diseases are the subject of internationally recognised definitions, as described by the World Organisation for Animal Health (OIE), and legislation for the purposes of maintaining poultry health, trade and disease control. This article, the first in a three‐part series, focuses on avian influenza, including influenza virus biology and the statutory definitions and epidemiology of the disease. In addition, key clinical and pathological features of avian influenza in different poultry hosts are described. Parts 2 and 3, which will be published in forthcoming issues of In Practice, will discuss, respectively, Newcastle disease and the investigation of poultry health problems with reference to avian notifiable diseases and differential diagnoses.
Metabolomics for the practising vet
Authors: Kirwan Jennifer
Published: September 2013

Imagine a world with no mystery illnesses, no diagnoses of exclusion and happy owners. Realistically, this is unlikely to happen in our lifetime. However, the promising new science of metabolomics may lead to a future of fewer medical mysteries, improved diagnostic criteria and better outcomes for some of the more frustrating cases. Metabolomics allows for hundreds of metabolites to be measured and then analysed using specialist techniques to equate what is being seen phenotypically with what is happening biochemically. Its potential for use by vets is currently limited to research, but in the future it may find its way into the clinic as a potential diagnostic aid. This article defines aspects of metabolomics, explains the basics of metabolomic studies and discusses the potential benefits of the technique to veterinary science.
Clinical approach to the dull donkey
Authors: Thiemann Alex
Published: September 2013

The ‘dull donkey’ is a general descriptive term used by owners and clinicians to identify a donkey presenting with varying degrees of depression, dullness and inappetence. These cases can be frustrating to diagnose and manage successfully. This article provides an overview of the most common causes of dullness in donkeys in the UK and suggests appropriate first‐line diagnostic and treatment options. It should be appreciated that, in many cases, dull donkeys may be very sick and may require high levels of intervention to recover. Such cases should be seen as priority patients.
Comparative theoretical studies of dinitromethyl- or trinitromethyl-modified derivatives of CL-20
Authors: Pan Yong , Zhu Weihua , Xiao Heming
Published: September 2013

The heats of formation (HOFs), energetic properties, strain energies, thermal stability, and impact sensitivity for a series of trinitromethyl- or dinitromethyl-modified CL-20 derivatives were studied by using density functional theory. It is found that the trinitromethyl group is an effective structural unit for improving the gas-phase HOFs and energetic properties of the derivatives. However, incorporating the dinitromethyl group into the parent compound is not favorable for increasing its HOFs and detonation properties. The effects of the dinitromethyl or trinitromethyl groups on the stability of the parent compound are discussed. The studies on strain energies show that the introduction of the trinitromethyl group intensifies the strain of the cage skeleton for the title compounds, whereas for the dinitromethyl groups, the case is quite the contrary. An analysis of the bond dissociation energies for several relatively weak bonds suggests that the substitution of the dinitromethyl or trinitromethyl group decreases the thermal stability of the derivatives. The C−NO2 bond in the dinitromethyl or trinitromethyl group is the weakest one and the homolysis of the C−NO2 bond may be the initial step in thermal decomposition. In addition, according to the calculated free space per molecule, the introduction of the dinitromethyl or trinitromethyl group increases the impact sensitivities of the derivatives. Considering the detonation performance, thermal stability, and impact sensitivity, six compounds can be regarded as the target high-energetic compounds.
Linear analysis of the stability of particle-laden stratified shear layers
Authors: Khavasi Ehsan , Firoozabadi Bahar , Afshin Hossein
Published: September 2013

Hydrodynamic instabilities at the interface of stratified shear layers could occur in various modes and have an important role in the mixing process. In this work, the linear stability analysis in the temporal framework is used to study the stability characteristics of a particle-laden stratified two-layer flow for two different background density profiles: smooth (hyperbolic tangent) and piecewise linear. The effect of parameters, such as bed slope, viscosity, and particle size, on the stability is also considered. The pseudospectral collocation method employing Chebyshev polynomials is used to solve two coupled eigenvalue equations. Based on the results, there are some differences in the stability characteristics of the two density profiles. In the case of R = 1 (R is the ratio of the shear layer thickness to the density layer thickness), the stability boundary in smooth profile is the transition from the unstable flow (where the dominant unstable mode is Kelvin–Helmholtz) to the stable one where in the piecewise linear profile this boundary is the transition from Kelvin–Helmholtz to the Holmboe mode. It is also shown that the unstable region increases with the bed slope and unstable modes amplify as the bed slope increases. For R = 5 the flow does not become stable by increasing the stratification in nonzero bed slope, and in some wavenumbers the Kelvin–Helmholtz and Holmboe modes coexist. In addition, by increasing the bed slope the growth rate of the Holmboe mode and the range of its existence decrease. As expected, the viscosity makes the current more stable, and for large values of the viscosity (small Reynolds number) the flow becomes stable at long waves (small wave numbers) for all bulk Richardson numbers. Existence of small particles does not change the instability characteristics so much, however, large particles make the flow more unstable.
Solvent polarity studies of highly fluorescent laser dye ADS740WS and its fluorescence quenching with silver nanoparticles
Authors: Tangod V.B. , Raikar Prasad , Mastiholi B.M. , Raikar U.S.
Published: September 2013

Determination of ground state and excited state dipole moments of a highly fluorescent laser dye molecule ADS740WS and comparison of excited state dipole moment by Lippert, Bakhashiev, Kawski–Chamma–Viallet, McRae, Suppan, and solvent polarity methods. Kamlet–Abboud–Taft and Katritzky multilinear analysis for characterizing the solvent contribution into spectral features of the dye has also been studied. Correlation analysis of spectroscopic data with multiple polarity parameters was carried out by multiple linear regression analysis. Optical absorption and fluorescence of ADS740WS in alcohol and other solvents with attachment of silver nanoparticles (AgNPs) shows quenching of absorption and fluorescence intensities. This is due to size, shape, and coupling between the AgNPs and the dye, and energy transfer between the dye and the AgNPs. Fluorescence quenching of ADS740WS leads to many applications notably for advancement in biomolecular labeling and fluorescence patterning and chemotherapy in cancer treatment.
DIFFUSION OF LITHIUM IN SILICON AFFECTED BY 60° MISFIT-DISLOCATION
Authors: ZHAO WEI , MENG QINGYUAN , YANG LIJUN , WANG CHAOYING
Published: September 2013

In this paper, the diffusion dynamics of Li atom in bulk Si with misfit (60°) dislocation has been investigated with the multi-scale simulation method. The results demonstrate that the dislocation core may confine the Li atom diffusion along the dislocation line, with its much larger binding energy and relatively smaller diffusion barrier compared to that in bulk Si . The reconstructions occurred in the dislocation core may open a low barrier route for the Li atoms entering into the core.
A COMPREHENSIVE SURVEY OF PETRI NET MODELING IN SOFTWARE ENGINEERING
Authors: HE XUDONG
Published: September 2013

Petri nets, a formal model for concurrent and distributed systems, have been widely applied in system modeling and analysis in almost every branch of computer science and many other scientific and engineering disciplines in the past half century. In this comprehensive survey, we review some major developments of Petri nets that have enhanced their modeling capabilities and in particular the methods to incorporate well-known software engineering development paradigms in Petri nets to support general software system modeling.
ENHANCING GOAL-ORIENTED SECURITY REQUIREMENTS ANALYSIS USING COMMON CRITERIA-BASED KNOWLEDGE
Authors: SAEKI MOTOSHI , HAYASHI SHINPEI , KAIYA HARUHIKO
Published: September 2013

Goal-oriented requirements analysis (GORA) is one of the promising techniques to elicit software requirements, and it is natural to consider its application to security requirements analysis. In this paper, we proposed a method for goal-oriented security requirements analysis using security knowledge which is derived from several security targets (STs) compliant to Common Criteria (CC, ISO/IEC 15408). We call such knowledge security ontology for an application domain (SOAD). Three aspects of security such as confidentiality, integrity and availability are included in the scope of our method because the CC addresses these three aspects. We extract security-related concepts such as assets, threats, countermeasures and their relationships from STs, and utilize these concepts and relationships for security goal elicitation and refinement in GORA. The usage of certificated STs as knowledge source allows us to reuse efficiently security-related concepts of higher quality. To realize our proposed method as a supporting tool, we use an existing method GOORE (goal-oriented and ontology-driven requirements elicitation method) combining with SOAD. In GOORE, terms and their relationships in a domain ontology play an important role of semantic processing such as goal refinement and conflict identification. SOAD is defined based on concepts in STs. In contrast with other goal-oriented security requirements methods, the knowledge derived from actual STs contributes to eliciting security requirements in our method. In addition, the relationships among the assets, threats, objectives and security functional requirements can be directly reused for the refinement of security goals. We show an illustrative example to show the usefulness of our method and evaluate the method in comparison with other goal-oriented security requirements analysis methods.
A CLUSTERING-BASED STRATEGY TO IDENTIFY COINCIDENTAL CORRECTNESS IN FAULT LOCALIZATION
Authors: MIAO YI , CHEN ZHENYU , LI SIHAN , ZHAO ZHIHONG , ZHOU YUMING
Published: September 2013

Coverage-based fault localization techniques leverage the coverage information to identify the faulty elements of a program. However, these techniques can be adversely affected by coincidental correctness, which occurs when the defect is executed but no failure is revealed. In this paper, we propose a clustering-based strategy to identify coincidental correctness in fault localization. The insight behind this strategy is that tests in the same cluster have similar behaviors. Thus a passed test in a cluster with many failed tests is highly possible to be coincidentally correct because it has the potential to execute the faulty elements as those failed ones do. We evaluated this technique from two aspects: the ability to identify coincidental correctness and the effectiveness to improve fault localization. The experimental results show that our strategy can alleviate the coincidental correctness problem and improve the effectiveness of fault localization.
ON THE TWISTED ALEXANDER POLYNOMIAL FOR REPRESENTATIONS INTO SL2(ℂ)
Authors: TRAN ANH T.
Published: September 2013

We study the twisted Alexander polynomial ΔK,ρof a knot K associated to a non-abelian representation ρ of the knot group into SL2(ℂ). It is known for every knot K that if K is fibered, then for every non-abelian representation, ΔK,ρis monic and has degree 4g(K) – 2 where g(K) is the genus of K. Kim and Morifuji recently proved the converse for 2-bridge knots. In fact they proved a stronger result: if a 2-bridge knot K is non-fibered, then all but finitely many non-abelian representations on some component have ΔK,ρnon-monic and degree 4g(K) – 2. In this paper, we consider two special families of non-fibered 2-bridge knots including twist knots. For these families, we calculate the number of non-abelian representations where ΔK,ρis monic and calculate the number of non-abelian representations where the degree of ΔK,ρis less than 4g(K) – 2.
4-Carboxymethyl-8-methyl-7-oxycoumarin substituted zinc, cobalt and indium phthalocyanines: electrochemical and photochemical properties
Authors: Çalık Ali Emre , Köksoy Baybars , Orman Efe Baturhan , Durmuş Mahmut , Özkaya Ali Rıza , Bulut Mustafa
Published: September 2013

In this study, the novel tetra-substituted Zn ( II )(3), Co ( II )(4) and In ( III )acetate (5) phthalocyanines were synthesized by cyclotetramerization reactions of 7-(2,3-dicyanophenoxy)-8-methylcoumarin-4-acetic acid (2) with corresponding metal salts. All the new compounds have been characterized by MALDI-TOF mass, FT-IR and UV-vis spectra, and elemental analysis as well. The electrochemical, in situ spectroelectrochemical and photochemical properties of tetra-substituted Zn ( II ), Co ( II ) and In ( III )acetate phthalocyanines were also investigated.
NEW RAMANUJAN TYPE CONGRUENCE MODULO 7 FOR 4-COLORED GENERALIZED FROBENIUS PARTITIONS
Authors: LIN BERNARD L. S.
Published: September 2013

In this brief note, we prove one unexpected Ramanujan type congruence modulo 7 for the number cϕ4(n) of generalized Frobenius partitions of n with four colors.
RAMANUJAN-TYPE CONGRUENCES FOR SEVERAL PARTITION FUNCTIONS
Authors: ZHANG WENLONG , WANG CHUN
Published: September 2013

Inspired by the recent work of Baruah and Ojah, we investigate several partition functions and establish some interesting Ramanujan-type congruences.
The Nexus of Environmental Quality and Livestock Welfare
Authors: Place Sara E. , Mitloehner Frank M.
Published: September 2013

In recent years, the livestock production industry has been receiving pressure to assess and improve production practices in two seemingly unrelated areas: environmental quality and animal welfare. In this article, we argue that the nexus of these two areas of study should be a priority for future research and that the integration of these disciplines in research, extension, and education efforts has the potential to improve the sustainability of production livestock agriculture.
Financial Contagion and Network Analysis
Authors: Summer Martin
Published: September 2013

Network models of interbank exposures allow the mapping of the complex web of financial linkages among many institutions and address issues of system stability and contagion risk. Although existing models cover a fair amount of ground in explaining how network structure can lead to default cascades and in quantifying the likelihood and the impact of default cascades through balance-sheet mechanics, the literature has shortcomings in explaining how shocks are potentially amplified through the network of exposures. These amplification mechanisms seem to be very important in financial crises. This review discusses the main conceptual ideas behind network models of contagion, the major findings of this literature, as well as some limitations of existing models.
Empirical Cross-Sectional Asset Pricing
Authors: Nagel Stefan
Published: September 2013

I review recent research efforts in the area of empirical cross-sectional asset pricing. I start by summarizing the evidence on cross-sectional return predictability and the failure of standard (consumption) capital asset pricing models (CAPMs) and their conditional versions to explain these predictability patterns. Part of the recent literature focuses on ad hoc factor models, which summarize the cross section of expected returns in parsimonious form, or on production-based approaches, which suggest links between firm characteristics and expected returns. Without imposing restrictions on investor preferences and beliefs, neither one of these two approaches can answer the question of why investors price assets the way they do. Within the rational expectations paradigm, recent research that imposes such restrictions has focused on the intertemporal CAPM (ICAPM), long-run risks models, as well as frictions and liquidity risk. Approaches based on investor sentiment have focused on the development of empirical proxies for sentiment and for the limits to arbitrage that allow sentiment to affect prices. Empirical work that considers learning and adaptation of investors has worked with out-of-sample tests of cross-sectional predictability.
Control of Nuclear Activities by Substrate-Selective and Protein-Group SUMOylation
Authors: Jentsch Stefan , Psakhye Ivan
Published: September 2013

Reversible modification of proteins by SUMO (small ubiquitin-like modifier) affects a large number of cellular processes. In striking contrast to the related ubiquitin pathway, only a few enzymes participate in the SUMO system, although this pathway has numerous substrates as well. Emerging evidence suggests that SUMOylation frequently targets entire groups of physically interacting proteins rather than individual proteins. Protein-group SUMOylation appears to be triggered by recruitment of SUMO ligases to preassembled protein complexes. Because SUMOylation typically affects groups of proteins that bear SUMO-interaction motifs (SIMs), protein-group SUMOylation may foster physical interactions between proteins through multiple SUMO-SIM interactions. Individual SUMO modifications may act redundantly or additively, yet they may mediate dedicated functions as well. In this review, we focus on the unorthodox principles of this pathway and give examples for SUMO-controlled nuclear activities. We propose that collective SUMOylation is typical for nuclear assemblies and argue that SUMO serves as a distinguishing mark for functionally engaged protein fractions.
Adoption: Biological and Social Processes Linked to Adaptation
Authors: Grotevant Harold D. , McDermott Jennifer M.
Published: September 2013

Children join adoptive families through domestic adoption from the public child welfare system, infant adoption through private agencies, and international adoption. Each pathway presents distinctive developmental opportunities and challenges. Adopted children are at higher risk than the general population for problems with adaptation, especially externalizing, internalizing, and attention problems. This review moves beyond the field's emphasis on adoptee–nonadoptee differences to highlight biological and social processes that affect adaptation of adoptees across time. The experience of stress, whether prenatal, postnatal/preadoption, or during the adoption transition, can have significant impacts on the developing neuroendocrine system. These effects can contribute to problems with physical growth, brain development, and sleep, activating cascading effects on social, emotional, and cognitive development. Family processes involving contact between adoptive and birth family members, co-parenting in gay and lesbian adoptive families, and racial socialization in transracially adoptive families affect social development of adopted children into adulthood.
Beyond Motivation: Job and Work Design for Development, Health, Ambidexterity, and More
Authors: Parker Sharon K.
Published: September 2013

Much research shows it is possible to design motivating work, which has positive consequences for individuals and their organizations. This article reviews research that adopts this motivational perspective on work design, and it emphasizes that it is important to continue to refine motivational theories. In light of continued large numbers of poor-quality jobs, attention must also be given to influencing practice and policy to promote the effective implementation of enriched work designs. Nevertheless, current and future work-based challenges mean that designing work for motivation is necessary but insufficient. This review argues that work design can be a powerful vehicle for learning and development, for maintaining and enhancing employees' physical and mental health, and for achieving control and flexibility simultaneously (for example, in the form of ambidexterity); all these outcomes are important given the challenges in today's workplaces. The review concludes by suggesting methodological directions.
Distributed Fault-Tolerant Event Region Detection of Wireless Sensor Networks
Authors: Duh Dyi-Rong , Li Ssu-Pei , Cheng Victor W.
Published: September 2013

This work provides a distributed fault-tolerant event region detection algorithm for wireless sensor networks. The proposed algorithm can identify faulty and fault-free sensors and ignore the abnormal readings to avoid false alarm. Moreover, every event region can also be detected and identified. Simulation results show that fault detection accuracy (FDA) is greater than 92%, false alarm rate (FAR) is near 0%, and event detection accuracy (EDA) is greater than 99% under uniform distribution. FDA is greater than 92%, FAR is less than 1.2%, and EDA is greater than 88% under random distribution when sensor fault probability is less than 0.3.
An Unusual Case of Stercoral Perforation in a Patient with 86 cm of Small Bowel
Authors: Okullo Alfin , Alsnih Ghiyath , Kwok Titus
Published: September 2013

A 77-year-old male who previously had extensive enterectomy due to ischaemic gut with loss of all but 86 cm of jejunum in addition to a right hemicolectomy presented to the emergency department (ED) with abdominal pain and constipation of 12-day duration. Abdominal imaging with X-ray and CT revealed pneumoperitoneum in addition to a grossly redundant and faecally loaded colon. At laparotomy, rectal perforation was found. In view of the patient’s advanced age, comorbidities, and the absence of intraperitoneal faecal contamination, manual disimpaction followed by wedge resection and primary closure of the perforation was done. On postop day 11, a perforation in the sigmoid colon with free subdiaphragmatic gas was picked up on CT after a work up for abdominal tenderness. In the absence of peritonism and other signs of deterioration, conservative management was chosen with subsequent uneventful recovery for the patient.
Polyacrylic Acid Functionalized Nanographene as a Nanocarrier for Loading and Controlled Release of Doxorubicin Hydrochloride
Authors: Chen Yunping , Qi Yuanyuan , Liu Bin
Published: September 2013

Graphene nanosheets (GNSs) were synthesized by direct current arc discharge and subsequently functionalized by highly hydrophilic polyacrylic acid (PAA). The loading and release of doxorubicin hydrochloride (DOX) on PAA‐functionalized GNSs (PAA‐GNSs) were investigated. PAA‐GNSs were successfully prepared and verified by atomic force microscope (AFM), Fourier‐transform infrared (FTIR) and ultraviolet‐visible (UV‐vis) spectroscopes, and thermogravimetric analysis (TGA). The PAA‐GNSs contained about 10 wt% PAA which significantly improved the solubility of GNSs in aqueous media. The efficient loading of DOX onto the PAA‐GNSs is as high as 2.404 ± 0.167 mg/mg at the DOX concentration of 0.36 mg/mL. Furthermore, the PPA‐GNSs showed strong pH‐dependent behavior and efficient slow release ability. Therefore, PAA‐GNSs are promising new materials for biological and medical applications.