bluuebunny/crossref_metadata_2025 huggingface dataset:
Second Law Analysis of Aerodynamic Losses: Results for a Cambered Vane With and Without Film Cooling
Authors: Ligrani Phil , Sik Jin Jae
Published: June 2013

Results of second law analysis of experimentally-measured aerodynamic losses are presented for a cambered vane with and without film cooling, including comparisons with similar results from a symmetric airfoil. Included are distributions of local entropy creation, as well as mass-averaged magnitudes of global exergy destruction. The axial chord length of the cambered vane is 4.85 cm, the true chord length is 7.27 cm, and the effective pitch is 6.35 cm. Data are presented for three airfoil Mex distributions (including one wherein the flow is transonic), magnitudes of inlet turbulence intensity from 1.1% to 8.2%, and ks/cx surface roughness values of 0, 0.00108, and 0.00258. The associated second law aerodynamics losses are presented for two different measurement locations downstream of the vane trailing edge (one axial chord length and 0.25 axial chord length). The surface roughness, when present, simulates characteristics of the actual roughness which develops on operating turbine airfoils from a utility power engine, over long operating times, due to particulate deposition and to spallation of thermal barrier coatings. Quantitative surface roughness characteristics which are matched include equivalent sandgrain roughness size, as well as the irregularity, nonuniformity, and the three-dimensional irregular arrangement of the roughness. Relative to a smooth, symmetric airfoil with no film cooling at low Mach number and low freestream turbulence intensity, overall, the largest increases in exergy destruction occur with increasing Mach number, and increasing surface roughness. Important variations are also observed as airfoil camber changes. Progressively smaller mass-averaged exergy destruction increases are then observed with changes of freestream turbulence intensity, and different film cooling conditions. In addition, the dependences of overall exergy destruction magnitudes on mainstream turbulence intensity and freestream Mach number are vastly different as level of vane surface roughness changes. When film cooling is present, overall mass-averaged exergy destruction magnitudes are significantly less than values associated with increased airfoil surface roughness for both the cambered vane and the symmetric airfoil. Dimensional exergy destruction values (associated with wake aerodynamic losses) for the symmetric airfoil with film cooling are then significantly higher than data from the cambered vane with film cooling, when compared at a particular blowing ratio.
Processing advances for localization of beaked whales using time difference of arrival
Authors: Baggenstoss Paul M.
Published: June 2013

This paper is concerned with the localization of clicking Blainville's beaked whales (Mesoplodon densirostris) using an array of widely spaced bottom-mounted hydrophones. A set of signal and data processing advances are presented that together make reliable tracking a possibility. These advances include a species-specific detector, elimination of spurious time-difference-of-arrival (TDOA) estimates, improved tracking of TDOA estimates, positive association of TDOA estimates using different hydrophone pairs, and joint localization of multiple whales. A key innovation in three of these advances is the principle of click-matching. The methods are demonstrated using real data.
Assessing the low frequency acoustic characteristics of Macrocystis pyrifera, Egregia menziessi, and Laminaria solidungula
Authors: Wilson Christopher J. , Wilson Preston S. , Dunton Kenneth H.
Published: June 2013

The acoustic properties of kelp forests are not well known, but are of interest for the development of environmental remote sensing applications. This study examined the low-frequency (0.2–4.5 kHz) acoustic properties of three species of kelp (Macrocystis pyrifera, Egregia menziessi, and Laminaria solidungula) using a one-dimensional acoustic resonator. Acoustic observations and measurements of kelp morphology were then used to test the validity of Wood's multi-phase medium model in describing the acoustic behavior of the kelp. For Macrocystis and Egregia, the two species of kelp possessing pneumatocysts, the change in sound speed was highly dependent on the volume of free air contained in the kelp. The volume of air alone, however, was unable to predict the effective sound speed of the multi-phase medium using a simple two-phase (air + water) form of Wood's model. A separate implementation of this model (frond + water) successfully yielded the acoustic compressibility of the frond structure for each species (Macrocystis = 1.39 ± 0.82 × 10−8 Pa−1; Egregia = 2.59 ± 5.75 × 10−9 Pa−1; Laminaria = 8.65 ± 8.22 × 10−9 Pa−1). This investigation demonstrates that the acoustic characteristics of kelp are species-specific, biomass-dependent, and differ between species with and without pneumatocyst structures.
Near resonance acoustic scattering from organized schools of juvenile Atlantic bluefin tuna (Thunnus thynnus)
Authors: Weber Thomas C. , Lutcavage Molly E. , Schroth-Miller Madeline L.
Published: June 2013

Schools of Atlantic bluefin tuna (Thunnus thynnus) can exhibit highly organized spatial structure within the school. This structure was quantified for dome shaped schools using both aerial imagery collected from a commercial spotter plane and 400 kHz multibeam echo sounder data collected on a fishing vessel in 2009 in Cape Cod Bay, MA. Observations from one school, containing an estimated 263 fish within an approximately ellipsoidal volume of 1900 m3, were used to seed an acoustic model that estimated the school target strength at frequencies between 10 and 2000 Hz. The fish's swimbladder resonance was estimated to occur at approximately 50 Hz. The acoustic model examined single and multiple scattering solutions and also a completely incoherent summation of scattering responses from the fish. Three levels of structure within the school were examined, starting with fish locations that were constrained by the school boundaries but placed according to a Poisson process, then incorporating a constraint on the distance to the nearest neighbor, and finally adding a constraint on the bearing to the nearest neighbor. Results suggest that both multiple scattering and spatial organization within the school should be considered when estimating the target strength of schools similar to the ones considered here.
Converting Sabine absorption coefficients to random incidence absorption coefficients
Authors: Jeong Cheol-Ho
Published: June 2013

Absorption coefficients measured by the chamber method are referred to as Sabine absorption coefficients, which sometimes exceed unity due to the finite size of a sample and non-uniform intensity in the reverberation chambers under test. In this study, conversion methods from Sabine absorption coefficients to random incidence absorption coefficients are proposed. The overestimations of the Sabine absorption coefficient are investigated theoretically based on Miki's model for porous absorbers backed by a rigid wall or an air cavity, resulting in conversion factors. Additionally, three optimizations are suggested: An optimization method for the surface impedances for locally reacting absorbers, the flow resistivity for extendedly reacting absorbers, and the flow resistance for fabrics. With four porous type absorbers, the conversion methods are validated. For absorbers backed by a rigid wall, the surface impedance optimization produces the best results, while the flow resistivity optimization also yields reasonable results. The flow resistivity and flow resistance optimization for extendedly reacting absorbers are also found to be successful. However, the theoretical conversion factors based on Miki's model do not guarantee reliable estimations, particularly at frequencies below 250 Hz and beyond 2500 Hz.
Inaccuracy in the treatment of multiple-order diffraction by secondary-edge-source methods
Authors: Summers Jason E.
Published: June 2013

Existing secondary-edge-source methods based on the Biot–Tolstoy solution for diffraction from an infinite wedge compute multiple-order diffraction by cascading the integration over secondary sources used to determine first-order diffraction from the edge. It is demonstrated here that this approach errs in some important cases because it neglects slope-diffraction contributions. This error is illustrated by considering the case of an infinite slit in a thin, hard screen. Comparisons with measurements for this case and analytical solutions for the case of a circular aperture in a thin, hard screen are used as a basis to gauge the magnitude of the error.
Numerical and analytical calculation of modal excitability for elastic wave generation in lossy waveguides
Authors: Treyssède Fabien , Laguerre Laurent
Published: June 2013

In the analysis of elastic waveguides, the excitability of a given mode is an important feature defined by the displacement-force ratio. Useful analytical expressions have been provided in the literature for modes with real wavenumbers (propagating modes in lossless waveguides). The central result of this paper consists in deriving a generalized expression for the modal excitability valid for modes with complex wavenumbers (lossy waveguides or non-propagating modes). The analysis starts from a semi-analytical finite element method and avoids solving the left eigenproblem. Analytical expressions of modal excitability are then deduced. It is shown that the fundamental orthogonality property to be used indeed corresponds to a form of Auld's real orthogonality relation, involving both positive- and negative-going modes. Finally, some results obtained from the generalized excitability are compared to the approximate lossless expression.
A bond graph approach to modeling the anuran vocal production system
Authors: Kime Nicole M. , Ryan Michael J. , Wilson Preston S.
Published: June 2013

Air-driven vocal production systems such as those found in mammals, birds, and anurans (frogs and toads) combine pneumatic and mechanical elements in species-specific ways to produce a diversity of communication signals. This study uses bond graphs to model a generalized anuran vocal production system. Bond graphs allow an incremental approach to modeling dynamic physical systems involving different domains. Anurans provide an example of how signal diversity results from variation in the structure and behavior of vocal system elements. This paper first proposes a bond graph model of the integrated anuran vocal system as a framework for future study. It then presents a simulated submodel of the anuran sound source that produces sustained oscillations in vocal fold displacement and air flow through the larynx. The modeling approach illustrated here should prove of general applicability to other biological sound production systems, and will allow researchers to study the biomechanics of vocal production as well as the functional congruence and evolution of groups of traits within integrated vocal systems.
Long-term effects of noise reduction measures on noise annoyance and sleep disturbance: The Norwegian facade insulation study
Authors: Amundsen Astrid H. , Klæboe Ronny , Aasvang Gunn Marit
Published: June 2013

The Norwegian facade insulation study includes one pre-intervention and two post-intervention surveys. The facade-insulating measures reduced indoor noise levels by 7 dB on average. Before the intervention, 43% of the respondents were highly annoyed by noise. Half a year after the intervention, the proportion of respondents who were highly annoyed by road traffic noise had been significantly reduced to 15%. The second post-intervention study (2 yr after the first post-intervention study) showed that the proportion of highly annoyed respondents had not changed since the first post-intervention study. The reduction in the respondents' self-reported sleep disturbances (due to traffic noise) also remained relatively stable from the first to the second post-intervention study. In the control group, there were no statistically significant differences in annoyance between the pre-intervention and the two post-intervention studies. Previous studies of traffic changes have reported that people “overreact” to noise changes. This study indicated that when considering a receiver measure, such as facade insulation, the effect of reducing indoor noise levels could be predicted from exposure-response curves based on previous studies. Thus no evidence of an “overreaction” was found.
Cross-language similarities and differences in the uptake of place information
Authors: Wagner Anita
Published: June 2013

Cross-language differences in the use of coarticulatory cues for the identification of fricatives have been demonstrated in a phoneme detection task: Listeners with perceptually similar fricative pairs in their native phoneme inventories (English, Polish, Spanish) relied more on cues from vowels than listeners with perceptually more distinct fricative contrasts (Dutch and German). The present gating study further investigated these cross-language differences and addressed three questions. (1) Are there cross-language differences in informativeness of parts of the speech signal regarding place of articulation for fricative identification? (2) Are such cross-language differences fricative-specific, or do they extend to the perception of place of articulation for plosives? (3) Is such language-specific uptake of information based on cues preceding or following the consonantal constriction? Dutch, Italian, Polish, and Spanish listeners identified fricatives and plosives in gated CV and VC syllables. The results showed cross-language differences in the informativeness of coarticulatory cues for fricative identification: Spanish and Polish listeners extracted place of articulation information from shorter portions of VC syllables. No language-specific differences were found for plosives, suggesting that greater reliance on coarticulatory cues did not generalize to other phoneme types. The language-specific differences for fricatives were based on coarticulatory cues into the consonant.
Generation place of the long- and short-latency components of transient-evoked otoacoustic emissions in a nonlinear cochlear model
Authors: Moleti Arturo , Mohsin Al-Maamury Adnan , Bertaccini Daniele , Botti Teresa , Sisto Renata
Published: June 2013

Time-domain numerical solutions of a nonlinear active cochlear model forced by click stimuli are analyzed with a time-frequency wavelet technique to identify the components of the otoacoustic response associated with different generation mechanisms/places. Previous experimental studies have shown evidence for the presence of at least two components in the transient otoacoustic response: A long-latency response, growing compressively with increasing stimulus level, and a shorter-latency response, characterized by faster growth. The possible mechanisms for the generation of the two components are discussed using the results of the numerical simulations. The model is a one-dimensional (1-D) transmission line model with nonlinear and nonlocal active terms representing the anti-damping action of the “cochlear amplifier.” The dependence on the stimulus level of latency and level was measured for the different components of the response. The generation mechanisms/places of the different components were identified by varying the stimulus level and by turning off the cochlear roughness in well-defined cochlear regions. The results suggest that reflections from roughness coming from basal regions of the cochlea may give a relevant contribution to the early otoacoustic response, whereas nonlinear mechanisms seem to produce a much smaller additional contribution.
Masking functions and fixed-signal functions for low-level 1000-Hz tones
Authors: Shepherd Daniel , Hautus Michael J. , Jesteadt Walt
Published: June 2013

Masking functions and fixed-signal functions were constructed using a narrow range of pedestal intensities for 10-ms, 1000-Hz gated tones. Data from three experiments agreed with previously reported data, clearly demonstrating negative masking and the pedestal effect. The data extend earlier findings by showing (1) the resilience of the pedestal effect when a background noise masker is introduced; (2) a possible indifference of the fixed-signal function to stimulus duration; (3) the ability of a set of psychometric functions to produce both masking and fixed-signal functions; (4) depending on method, the impact of unit choice on the interpretation of both the pedestal effect and negative masking data. Results are discussed in relation to current psychophysical models, and suggest that accounting for the auditory system's sensitivity to differences in low-level sounds remains a challenge.
Time-domain solver in curvilinear coordinates for outdoor sound propagation over complex terrain
Authors: Dragna Didier , Blanc-Benon Philippe , Poisson Franck
Published: June 2013

The current work aims at developing a linearized Euler equations solver in curvilinear coordinates to account for the effects of topography on sound propagation. In applications for transportation noise, the propagation environment as well as the description of acoustic sources is complex, and time-domain methods have proved their capability to deal with both atmospheric and ground effects. First, equations in curvilinear coordinates are examined. Then time-domain boundary conditions initially proposed for a Cartesian coordinate system are implemented in the curvilinear solver. Two test cases dealing with acoustic scattering by an impedance cylinder in a two-dimensional geometry and by an impedance sphere in a three-dimensional geometry are considered to validate the boundary conditions. Accurate solutions are obtained for both rigid and impedance surfaces. Finally, the solver is used to examine a typical outdoor sound propagation problem. It is shown that it is well-suited to study coupled effects of topography, mixed impedance ground and meteorological conditions.
Passive sonic detection and ranging for locating sound sources
Authors: Wu Sean F. , Zhu Na
Published: June 2013

A passive sonic detection and ranging (SODAR) technology is developed to locate sound sources that emit arbitrarily time-dependent signals in a typical environment encountered in practice in real time. This passive SODAR is built on a comprehensive approach including the pre-processing of input data to enhance the signal-to-noise ratio, acoustic modeling of sound radiation from a point source, iterative triangulations, and post-processing of output data to ensure the accuracy in source localization. Moreover, it employs an optimization process to extend the source detection range and improve the source localization accuracy in a highly non-ideal environment that involves a large number of unspecified reflected and diffracted sound waves. This is accomplished through computations based on the source locations predicted by the individual units of four microphones that are not lying on the same plane. Experimental results confirm that passive SODAR works for arbitrarily time-dependent signals that include continuous, transient, impulsive, random, narrow-, and broadband sounds with frequencies above 20 Hz. The minimum number of microphones that are required in passive SODAR is six. These microphones can be mounted anywhere as long as they are not on the same plane and the lines of sight from sound sources remain unblocked.
Infants' detection and discrimination of sounds in modulated maskers
Authors: Werner Lynne A.
Published: June 2013

Adults and 7-month-old infants were compared in detection and discrimination of sounds in modulated maskers. In two experiments, the level of a target sound was varied to equate listeners' performance in unmodulated noise, and performance was assessed at that level in a noise modulated with the envelope of single-talker speech. While adults' vowel discrimination and tone detection were better in the modulated than in the unmodulated masker, infants' vowel discrimination was poorer in the modulated than in the unmodulated masker. Infants' tone detection was the same in the two maskers. In two additional experiments, each age group was tested at one level with order of testing in modulated and unmodulated maskers counterbalanced across subjects. Both infants and adults discriminated between vowels better in single-talker modulated and sinusoidally amplitude modulated (SAM) maskers than in an unmodulated masker, but infants' modulated-unmodulated difference was smaller than than that of adults. Increasing the modulation depth of the SAM masker did not affect the size of infants' modulated-unmodulated difference. However, infants' asymptotic performance in a modulated masker limits the extent to which their performance could improve. Infants can make use of information in masker dips, but masker modulation may also interfere with their ability to process the target.
Spherical array processing for acoustic analysis using room impulse responses and time-domain smoothing
Authors: Huleihel Nejem , Rafaely Boaz
Published: June 2013

Room impulse responses (RIRs) have been widely used for room acoustics analysis. One of the major objectives in room acoustics analysis is characterizing the directions of arrival (DOA) of the direct sound and early room reflections. In the past, spherical microphone arrays have been used to sample the sound field, taking advantage of their spatial symmetry, and various optimal array processing methods have been suggested for DOA estimation. However, these methods fail when the sound field is composed of highly correlated components, such as room reflections, since the cross-spectrum matrix may be of deficient rank. Recently, a preprocessing method incorporating smoothing of the cross-correlation matrix in the frequency domain has been suggested to overcome the rank deficiency. However, when using low-order spherical arrays, this method also fails due to the need to estimate the DOA of a group of reflections simultaneously. In this paper, an alternative time-domain smoothing approach is suggested. The method utilizes the time behavior of the RIR to separate early reflections, together with representation of the signal in the spherical-harmonics domain, to achieve improved performance over current methods. Simulation and experimental studies illustrate the limitations of the former method and the advantages of the suggested method.
Response to Comment on “Drug Screening for ALS Using Patient-Specific Induced Pluripotent Stem Cells”
Authors: Egawa Naohiro , Kitaoka Shiho , Tsukita Kayoko , Naitoh Motoko , Takahashi Kazutoshi , Yamamoto Takuya , Adachi Fumihiko , Kondo Takayuki , Okita Keisuke , Asaka Isao , Aoi Takashi , Watanabe Akira , Yamada Yasuhiro , Morizane Asuka , Takahashi Jun , Ayaki Takashi , Ito Hidefumi , Yoshikawa Katsuhiro , Yamawaki Satoko , Suzuki Shigehiko , Watanabe Dai , Hioki Hiroyuki , Kaneko Takeshi , Makioka Kouki , Okamoto Koichi , Takuma Hiroshi , Tamaoka Akira , Hasegawa Kazuko , Nonaka Takashi , Hasegawa Masato , Kawata Akihiro , Yoshida Minoru , Nakahata Tatsutoshi , Takahashi Ryosuke , Marchetto Maria C. N. , Gage Fred H. , Yamanaka Shinya , Inoue Haruhisa
Published: June 2013

Our work and the study of Bilican
et al.
highlight the need for complementary assays to detect subtle phenotypic differences between control and mutant induced pluripotent stem cell lines.
The Source of Youth and Longevity Revealed?
Authors: Eid Tore
Published: June 2013

The hypothalamus controls whole-body aging via immune-neuroendocrine mechanisms.
Deep digital flexor tendon injury within the hoof capsule; does lesion type or location predict prognosis?
Authors: Cillán‐García E. , Milner P. I. , Talbot A. , Tucker R. , Hendey F. , Boswell J. , Reardon R. J. M. , Taylor S. E.
Published: June 2013

The type and location of deep digital flexor tendon (DDFT) lesions may be important in predicting outcome. The objectives of this study were to determine the frequency of different types of DDFT lesions within the hoof capsule and to determine whether lesion type predicts return to athletic activity. Lesions of the DDFT were divided into: core lesions, dorsal border lesions and parasagittal splits. Lesion location was documented, and follow‐up information was obtained by telephone survey at least 18 months after diagnosis. Of 168 horses with primary DDFT injury, 54 horses had dorsal border lesions, 59 had parasagittal splits and 55 had core lesions. Twenty‐five per cent of all horses returned to previous levels of athletic activity within 18 months of MRI evaluation. Horses with complete splits or core lesions of the DDFT were significantly less likely to return to some level of athletic activity than horses with dorsal border lesions P<0.001. Dorsal border lesions of the DDFT appear to have a better prognosis than core lesions or parasagittal splits. This study provides additional information that may help clinicians predict the prognosis for different types of DDFT injury.
A canonical analysis of the massless superparticle
Authors: McKeon D.G.C.
Published: June 2013

The canonical structure of the action for a massless superparticle is considered in d = 2 + 1 and d = 3 + 1 dimensions. This is done by examining the contribution to the action of each of the components of the spinor θ present; no attempt is made to maintain manifest covariance. Upon using the Dirac bracket to eliminate the second class constraints arising from the canonical momenta associated with half of these components, we find that the remaining components have canonical momenta that are all first-class constraints. From these first class constraints, it is possible to derive the generator of half of the local Fermionic κ-symmetry of Siegel; which half is contingent upon the choice of which half of the momenta associated with the components of θ are taken to be second class constraints. The algebra of the generator of this Fermionic symmetry transformation is examined.
More sires may enhance offspring fitness in Northern Map Turtles (Graptemysgeographica)
Authors: Banger Nicola , Blouin-Demers Gabriel , Bulté Grégory , Lougheed Stephen C.
Published: June 2013

Sexual selection theory predicts that males should be promiscuous to maximize their reproductive success, while females should be choosy. Yet females of many taxa often produce progeny sired by multiple males, indicating that promiscuity can be important for the reproductive success of females. Promiscuity may enhance the fitness of females if it increases the genetic quality, or the genetic variety, and thus the viability of their offspring. We quantified the number of sires per clutch in a population of Northern Map Turtles (Graptemys geographica (LeSueur, 1817)) in Lake Opinicon, Ontario, Canada, and tested whether the number of sires affects several metrics of viability in hatchlings. Based on the most conservative estimate, at least 71% of clutches in this population are sired by multiple males, but there was no evidence that larger clutches are sired by more males. Clutches sired by more males had higher hatching success and survival, but the differences were not statistically significant. We did not find any effect of the number of sires on hatchling morphology or locomotor performance. Collectively, our results partially support the hypothesis that promiscuity can increase the reproductive success of female Northern Map Turtles.
Niche expansion of the shorthorn sculpin (Myoxocephalus scorpius) to Arctic waters is supported by a thermal independence of cardiac performance at low temperature
Authors: Farrell A.P. , Altimiras J. , Franklin C.E. , Axelsson M.
Published: June 2013

Cardiovascular adaptations that permit successful exploitation of polar marine waters by fish requires a capacity to negate or compensate for the depressive effects of low temperatures on physiological processes. Here, we examined the effects of acute and chronic temperature change on the maximum cardiac performance of shorthorn sculpin (Myoxocephalus scorpius (L., 1758)) captured above the Arctic Circle. Our aim was to establish if the sculpin’s success at low temperatures was achieved through thermal independence of cardiac function or via thermal compensation as a result of acclimation. Maximum cardiac performance was assessed at both 1 and 6 °C with a working perfused heart preparation that was obtained after fish had been acclimated to either 1 or 6 °C. Thus, tests were performed at the fish’s acclimation temperature and with an acute temperature change. Maximum cardiac output, which was relatively large (>50 mL·min−1·kg−1body mass) for a benthic fish at a frigid temperature, was found to be independent of both acclimation temperature and test temperature. While maximum β-adrenergic stimulation produced positive chronotropy at both acclimation temperatures, inotropic effects were weak or absent. We conclude that thermal independence of cardiac performance at low temperature likely facilitated the exploitation of polar waters by the shorthorn sculpin.
ASTROPHYSICAL EVIDENCE FOR AN EXTRA DIMENSION: PHENOMENOLOGY OF A KALUZA–KLEIN THEORY
Authors: PUGLIESE D. , MONTANI G.
Published: June 2013

In this brief review, we discuss the viability of a multi-dimensional geometrical theory with one compactified dimension. We discuss the case of a Kaluza–Klein (KK) fifth-dimensional theory, addressing the problem by an overview of the astrophysical phenomenology associated with this five-dimensional (5D) theory. By comparing the predictions of our model with the features of the ordinary (four-dimensional (4D)) Relativistic Astrophysics, we highlight some small but finite discrepancies, expectably detectible from the observations. We consider a class of static, vacuum solutions of free electromagnetic KK equations with three-dimensional (3D) spherical symmetry. We explore the stability of the particle dynamics in these spacetimes, the construction of self-gravitating stellar models and the emission spectrum generated by a charged particle falling on this stellar object. The matter dynamics in these geometries has been treated by a multipole approach adapted to the geometric theory with a compactified dimension.
THE EFFECT OF Z′ BOSON ON SAME-SIGN DIMUON CHARGE ASYMMETRY IN $B_q^0-\overline{B_q^0}$ SYSTEM
Authors: SAHOO S. , KUMAR M. , BANERJEE D.
Published: June 2013

The recent observation of the same-sign dimuon charge asymmetry in the B system by the D0 collaboration has 3.9σ deviation from the standard model prediction. However, the recent LHCb data on Bs neutral-meson mixing do not accommodate the D0 collaboration result. In this paper, considering the effect of Z′-mediated flavor-changing neutral currents in the [Formula: see text] mixing, the same-sign dimuon charge asymmetry is calculated. We find the same-sign dimuon charge asymmetry is enhanced from its SM prediction and provides signals for new physics beyond the SM.
QUANTUM MEASUREMENT SCHEMES RELATED TO FLAVOR-WEIGHTED ENERGIES
Authors: BERNARDINI A. E.
Published: June 2013

The framework of the generalized theory of quantum measurement provides some theoretical tools for computing flavor associated energies correlated to the von-Neumann entropy of a composed system. After defining flavor-averaged and flavor-weighted energies, that are respectively supported by nonselective (selective) quantum measurement schemes, the right correlation between the energies of flavor eigenstates and their measurement probabilities can be obtained. Our results from the composed quantum system framework show that the nonselective measurement scheme for computing flavor-weighted energies is consistent with predictions from single-particle quantum mechanics. As an application of our results, through the expressions for neutrino effective mass values, it is straightforwardly verified that cosmological background neutrino energy densities could be obtained from the coherent superposition of mass eigenstates.
QUANTUM CORRELATIONS IN THE "q-DEFORMED" WERNER STATE
Authors: LIU BO , XUE KANG , WANG GANGCHENG , SUN CHUNFANG , GOU LIDAN , DU GUIJIAO
Published: June 2013

We investigate quantum discord of the "q-deformed" Werner state via Yang–Baxterization approach. There are two parameters q and u in this "q-deformed" Werner state. The parameter u, which plays an important role in some typical models, is related to the probability of the "q-deformed" two-qubit spin singlet state in this study. The "q-deformed" parameter q is related to the single loop through d = q + q-1. When topological parameter d approaches 2 (i.e. q → 1), the "q-deformed" Werner state degenerates into the well-known Werner state. The results show that topological parameter d has great influence on quantum correlations of the "q-deformed" Werner state. When we fix the parameter u, the quantum correlations decrease with increasing the single loop d. When d approaches +∞ (i.e. q → 0+or +∞), quantum discord, geometric measure of quantum discord and entanglement all tend to 0. While d approaches 2 (i.e. q → 1), all of them just have the same results with the Werner state.
SECURITY ENHANCED DIRECT QUANTUM COMMUNICATION WITH HIGHER BIT-RATE
Authors: JAHANSHAHI S. , BAHRAMPOUR A. R. , ZANDI M. H.
Published: June 2013

A scheme for deterministic secure direct communication based on ping-pong protocol without restricting the security control only to a distinct control mode and debate via classical channel is proposed. It utilizes an entangled pair of qubits and presents a higher bit-rate transfer of information together with a higher security than ping-pong protocol. The security of protocol is enhanced by introducing a control factor for each message mode. It is explicitly showed that the protocol has a high degree of security against a class of individual attacks, and successfully resolves the famous Wojcik attack.
Synthesis of metal-free and zinc phthalocyanines containing 2-pyridyl-methyl pendant arm linked with NS4-donor macrocyclic moiety and their selectivity towards Cu(II) cations
Authors: Kabay Nilgün , Ocak Ümmühan , Gün Serhat , Gök Yaşar
Published: June 2013

New phthalonitrile (L1), metal-free phthalocyanine (H2Pc) and zinc-phthalocyanine (ZnPc) substituted in peripheral positions with 2-pyridyl methyl pendant arm linked mixed donor macrocyclic ligands have been prepared in a multi-step reaction sequence. The novel compounds were characterized by a combination of elemental anlaysis, 1 H NMR, 13 C NMR, IR, UV-vis and MS spectral data. The influence of metal cations such as Cd 2+, Zn 2+, Hg 2+, Al 3+, Fe 3+ and Cu 2+ on the spectroscopic properties of dinitrile compound L1 and free phthalocyanine H2Pc was investigated by means of absorption spectrophotometry. Spectrophotometric titrations were carried out with these ligands for Cu 2+ ion. The complex composition of Cu - L1 was found 1:1 by means of spectrophotometric titration data. The spectrophotometric method showed good sensitivity for Cu 2+ with linear range of 2.6 × 10-6 to 1.3 × 10-4 M with dinitrile compound.
Assessing relevance and trust of the deep web sources and results based on inter-source agreement
Authors: Balakrishnan Raju , Kambhampati Subbarao , Jha Manishkumar
Published: June 2013

Deep web search engines face the formidable challenge of retrieving high-quality results from the vast collection of searchable databases. Deep web search is a two-step process of selecting the high-quality sources and ranking the results from the selected sources. Though there are existing methods for both the steps, they assess the relevance of the sources and the results using the query-result similarity. When applied to the deep web these methods have two deficiencies. First is that they are agnostic to the correctness (trustworthiness) of the results. Second, the query-based relevance does not consider the importance of the results and sources. These two considerations are essential for the deep web and open collections in general. Since a number of deep web sources provide answers to any query, we conjuncture that the agreements between these answers are helpful in assessing the importance and the trustworthiness of the sources and the results. For assessing source quality, we compute the agreement between the sources as the agreement of the answers returned. While computing the agreement, we also measure and compensate for the possible
collusion
between the sources. This adjusted agreement is modeled as a graph with sources at the vertices. On this agreement graph, a quality score of a source, that we call
SourceRank
, is calculated as the stationary visit probability of a random walk. For ranking results, we analyze the second-order agreement between the results. Further extending SourceRank to multidomain search, we propose a source ranking sensitive to the query domains. Multiple domain-specific rankings of a source are computed, and these ranks are combined for the final ranking. We perform extensive evaluations on online and hundreds of Google Base sources spanning across domains. The proposed result and source rankings are implemented in the deep web search engine
Factal
. We demonstrate that the agreement analysis tracks source corruption. Further, our relevance evaluations show that our methods improve precision significantly over Google Base and the other baseline methods. The result ranking and the domain-specific source ranking are evaluated separately.
Nanoscale electronic synapses using phase change devices
Authors: Jackson Bryan L. , Rajendran Bipin , Corrado Gregory S. , Breitwisch Matthew , Burr Geoffrey W. , Cheek Roger , Gopalakrishnan Kailash , Raoux Simone , Rettner Charles T. , Padilla Alvaro , Schrott Alex G. , Shenoy Rohit S. , Kurdi Bülent N. , Lam Chung H. , Modha Dharmendra S.
Published: June 2013

The memory capacity, computational power, communication bandwidth, energy consumption, and physical size of the brain all tend to scale with the number of synapses, which outnumber neurons by a factor of 10,000. Although progress in cortical simulations using modern digital computers has been rapid, the essential disparity between the classical von Neumann computer architecture and the computational fabric of the nervous system makes large-scale simulations expensive, power hungry, and time consuming. Over the last three decades, CMOS-based neuromorphic implementations of “electronic cortex” have emerged as an energy efficient alternative for modeling neuronal behavior. However, the key ingredient for electronic implementation of any self-learning system—programmable, plastic Hebbian synapses scalable to biological densities—has remained elusive. We demonstrate the viability of implementing such electronic synapses using nanoscale phase change devices. We introduce novel programming schemes for modulation of device conductance to closely mimic the phenomenon of Spike Timing Dependent Plasticity (STDP) observed biologically, and verify through simulations that such plastic phase change devices should support simple correlative learning in networks of spiking neurons. Our devices, when arranged in a crossbar array architecture, could enable the development of synaptronic systems that approach the density (∼10
11
synapses per sq cm) and energy efficiency (consuming ∼1pJ per synaptic programming event) of the human brain.
Dual pillar spin-transfer torque MRAMs for low power applications
Authors: Mojumder Niladri N. , Fong Xuanyao , Augustine Charles , Gupta Sumeet K. , Choday Sri Harsha , Roy Kaushik
Published: June 2013

Electron-spin based data storage for on-chip memories has the potential for ultra-high density, low power consumption, very high endurance, and reasonably low read/write latency. In this article, we discuss the design challenges associated with spin-transfer torque (STT) MRAM in its state-of-the-art configuration. We propose an alternative bit cell configuration and three new genres of magnetic tunnel junction (MTJ) structures to improve STT-MRAM bit cell stabilities, write endurance, and reduce write energy consumption. The proposed multi-port, multi-pillar MTJ structures offer the unique possibility of electrical and spatial isolation of memory read and write. In order to realize ultralow power under process variations, we propose device, bit-cell and architecture level design techniques. Such design alternatives at multiple levels of design abstraction has been found to achieve substantially enhanced robustness, density, reliability and low power as compared to their charge-based counterparts for future embedded applications.
The Complexity of the Homotopy Method, Equilibrium Selection, and Lemke-Howson Solutions
Authors: Goldberg Paul W. , Papadimitriou Christos H. , Savani Rahul
Published: June 2013

We show that the widely used homotopy method for solving fixpoint problems, as well as the Harsanyi-Selten equilibrium selection process for games, are PSPACE-complete to implement. Extending our result for the Harsanyi-Selten process, we show that several other homotopy-based algorithms for finding equilibria of games are also PSPACE-complete to implement. A further application of our techniques yields the result that it is PSPACE-complete to compute any of the equilibria that could be found via the classical Lemke-Howson algorithm, a complexity-theoretic strengthening of the result in Savani and von Stengel [2006]. These results show that our techniques can be widely applied and suggest that the PSPACE-completeness of implementing homotopy methods is a general principle.
Near-Potential Games
Authors: Candogan Ozan , Ozdaglar Asuman , Parrilo Pablo A.
Published: June 2013

Potential games are a special class of games for which many adaptive user dynamics converge to a Nash equilibrium. In this article, we study properties of near-potential games, that is, games that are close in terms of payoffs to potential games, and show that such games admit similar limiting dynamics.

We first focus on finite games in strategic form. We introduce a distance notion in the space of games and study the geometry of potential games and sets of games that are equivalent, with respect to various equivalence relations, to potential games. We discuss how, given an arbitrary game, one can find a nearby game in these sets. We then study dynamics in near-potential games by focusing on continuous-time perturbed best response dynamics. We characterize the limiting behavior of this dynamics in terms of the upper contour sets of the potential function of a close potential game and approximate equilibria of the game. Exploiting structural properties of approximate equilibrium sets, we strengthen our result and show that for games that are sufficiently close to a potential game, the sequence of mixed strategies generated by this dynamics converges to a small neighborhood of equilibria whose size is a function of the distance from the set of potential games.

In the second part of the article, we study continuous games and show that our approach for characterizing the limiting sets in near-potential games extends to continuous games. In particular, we consider continuous-time best response dynamics and a variant of it (where players update their strategies only if there is at least
ε
utility improvement opportunity) in near-potential games where the strategy sets are compact and convex subsets of a Euclidean space. We show that these update rules converge to a neighborhood of equilibria (or the maximizer of the potential function), provided that the potential function of the nearby potential game satisfies some structural properties. Our results generalize the known convergence results for potential games to near-potential games.
Managing the Quality vs. Efficiency Trade-off Using Dynamic Effort Scaling
Authors: Chippa Vinay K. , Roy Kaushik , Chakradhar Srimat T. , Raghunathan Anand
Published: June 2013

Several current and emerging applications do not have a unique result for a given input; rather, functional correctness is defined in terms of output quality. Recently proposed design techniques exploit the inherent resilience of such applications and achieve improved efficiency (energy or performance) by foregoing correct execution of all the constituent computations. Hardware and software systems that are thus designed may be viewed as scalable effort systems, since they offer the capability to modulate the effort that they expend towards computation, thereby allowing for trade-offs between output quality and efficiency.

We propose the concept of
Dynamic Effort Scaling
(DES), which refers to dynamic management of the control knobs that are exposed by scalable effort systems. We argue the need for DES by observing that the degree of resilience often varies significantly across applications, across datasets, and even within a dataset. We propose a general conceptual framework for DES by formulating it as a feedback control problem, wherein the scaling mechanisms are regulated with the goal of maintaining output quality at or above a specified limit. We present an implementation of Dynamic Effort Scaling for recognition and mining applications and evaluate it for the support vector machines and K-means clustering algorithms under various application scenarios and datasets. Our results clearly demonstrate the benefits of the proposed approach---statically setting the scaling mechanisms leads to either significant error overshoot or significant opportunities for energy savings left on the table unexploited. In contrast, DES is able to effectively regulate the output quality while maximally exploiting the time-varying resiliency in the workload.
Survey of Stochastic Computing
Authors: Alaghi Armin , Hayes John P.
Published: June 2013

Stochastic computing (SC) was proposed in the 1960s as a low-cost alternative to conventional binary computing. It is unique in that it represents and processes information in the form of digitized probabilities. SC employs very low-complexity arithmetic units which was a primary design concern in the past. Despite this advantage and also its inherent error tolerance, SC was seen as impractical because of very long computation times and relatively low accuracy. However, current technology trends tend to increase uncertainty in circuit behavior and imply a need to better understand, and perhaps exploit, probability in computation. This article surveys SC from a modern perspective where the small size, error resilience, and probabilistic features of SC may compete successfully with conventional methodologies in certain applications. First, we survey the literature and review the key concepts of stochastic number representation and circuit structure. We then describe the design of SC-based circuits and evaluate their advantages and disadvantages. Finally, we give examples of the potential applications of SC and discuss some practical problems that are yet to be solved.