Interactions between test- and inducer-tone durations in induced loudness reduction

A tone usually declines in loudness when preceded by a more intense inducer tone. This phenomenon is called "loudness recalibration" or "induced loudness reduction" (ILR). The present study investigates how ILR depends on level, loudness, and duration. A 2AFC procedure was used to obtain loudness matches between 2500-Hz comparison tones and 500-Hz test tones at 60 and 70 dB SPL, presented with and without preceding 500-Hz inducer tones. For 200-ms test and comparison tones, the amount of ILR did not depend on inducer level (set at 80 dB SPL and above), but ILR was greater with 200- than with 5-ms inducers, even when both were equally loud. For 5-ms tones, ILR was as great with 5- as with 200-ms inducers and about as great as when test and inducer tones both lasted 200 ms. These results suggest that (1) neither the loudness nor the SPL of the inducer alone governs ILR, and (2) inducer duration must equal or exceed test-tone duration to yield maximal amounts of ILR. Further analysis indicates that the efferent system may be partly responsible for ILR of 200-ms test tones, but is unlikely to account for ILR of 5-ms tones.     

Potential carry-over effect in the measurement of induced loudness reduction

The majority of studies on induced loudness reduction (ILR) use an experimental paradigm that results in an underestimation of the amount of ILR. Most of those studies utilize loudness matches between tones of two different frequencies (a test tone and a comparison tone) with (experimental condition) and without (baseline condition) an inducer tone at the test frequency. The change in level of the comparison tone between the baseline and experimental conditions is the amount of ILR. In those experiments, the level of the comparison tone in the baseline condition tends to be substantially higher (often about 10 dB) than in the experimental condition. Because of this level difference, exposure to the baseline condition immediately prior to the experimental condition causes unintended ILR for the comparison tone. In this study, the delay between the baseline and experimental conditions was varied and it was determined that the amount of ILR is underestimated by about 30% and the variability is increased when the experimental condition is run immediately after the baseline condition. A second experiment using a Békésy-tracking procedure showed that ILR maximizes rapidly upon exposure to an inducer and decays over the course of several minutes after the inducer is removed.     

千新星简介

中子星—中子星或中子星—黑洞组成的致密双星系统在发生并合时,潮汐离心、碰撞挤压和吸积反馈等作用会导致约千分之几到百分之几倍太阳质量的物质被抛射到星际空间中。这些抛射物在加热机制的作用下可能达到较高的温度并快速膨胀,从而在紫外光学近红外波段发出一种快速变化的热辐射,即为千新星辐射。决定于抛射物的质量和不透明度,千新星的特征光变时标可估计在天到星期的量级。其辐射光度至少可达10&;amp;lt;sup&;amp;lt;41&;amp;lt;/sup&;amp;lt; erg s&;amp;lt;sup&;amp;lt;-1&;amp;lt;/sup&;amp;lt;的量级,具体决定于热源的性质,包括抛射物中通过快中子俘获过程形成的重元素的放射性衰变和并合产物可能的持续能量释放。千新星现象在2017年8月的GW170817引力波事件中被首次观测证实。     

漫谈社会物理学

进入21世纪以来,社会系统的复杂性已经逐步成为科学研究的热点领域,社会物理学利用物理学的思想和方法研究社会问题,已经取得了不少成果.文章首先简要回顾了社会物理学发展的历史,然后简要介绍了当代社会物理学的研究问题和成果,主要包括行人动力学、社会网络分析和舆论动力学三个方面.涉及社会力作用下行人的运动以及所表现出的群体行为、社会网络结构分析的基本概念,特别是社团结构的定义及其探测方法、基于自旋相互作用的舆论形成模型和相变行为等.     

漫谈社会物理学

进入21世纪以来,社会系统的复杂性已经逐步成为科学研究的热点领域,社会物理学利用物理学的思想和方法研究社会问题,已经取得了不少成果.文章首先简要回顾了社会物理学发展的历史,然后简要介绍了当代社会物理学的研究问题和成果,主要包括行人动力学、社会网络分析和舆论动力学三个方面.涉及社会力作用下行人的运动以及所表现出的群体行为、社会网络结构分析的基本概念,特别是社团结构的定义及其探测方法、基于自旋相互作用的舆论形成模型和相变行为等.     

浅说"混沌"

以单摆的强迫阻尼运动、罗伦兹系统及Ｌｏｇｉｓｔｉｃ映射为例,解说了混沌运动地主要特征,并介绍了混沌理论建立与与发展过程中的一些史话。     

Relation of loudness to loudness just noticeable difference of tone

1IntroductionAnimportantprobleminpsychoacousticsandaudiologyishowtointerprettherelationofloudnesstoloudnessjustnoticeabledifference(JND).ThefirstpostulateabouttherelationwajsproposedbyFechner,whosuggestedthatloudnessofatonewascoulltofloudnessJNDfromhearingthreshold.AccordingtoFechner'spostulateandWeber'slaw[2],theloudnessLofatonewithintensityIisL=Inl.(1)Butagreatnumberofexperimentsdemonstratedthatloudnessisapowerfunctionofintensity3[')3f4]L=I",(2)wheretheexponentorvariesslightlywithinten…     

An introduction to explicitR-parity violation

I discuss the theoretical motivations forR-parity violation, review the experimental bounds and outline the main changes in collider phenomenology compared to conservedR-parity.     

An introduction to ship hydroelasticity

The linear theory of ship hydroelasticity is not yet familiar in naval architecture, yet it provides the most powerful techniques of investigation available today. The background of that theory is explained in very simple terms, by using the concept of a “uniform ship”—that is, of a uniform floating beam. So rudimentary is this idealization of a ship that no claim can be made that numerical results have much practical significance; nevertheless, the underlying ideas are those employed in practical studies and some typical results are given for an actual ship (an old destroyer).     

An introduction to percolation theory

Percolation theory, the theory of the properties of classical particles interacting with a random medium, is of wide applicability and provides a simple picture exhibiting critical behaviour, the features of which are well understood and amenable to detailed calculation. In this review the concepts of percolation theory and the general features associated with the critical region about the onset of percolation are developed in detail. In particular, several dimensional invariants are examined which make it possible to unify much of the available information, and to extend the insights of percolation theory to processes which have not yet received numerical study. The compilation of the results of percolation theory, both exact and numerical, is believed to be complete through 1970. A selective bibliography is given. In a concluding chapter several recent applications of percolation theory to classical and to quantum mechanical problems are discussed.     

An adaptive procedure for categorical loudness scaling

In this study, an adaptive procedure for categorical loudness scaling is introduced and evaluated. The procedure adjusts the presentation levels to the subject's individual auditory dynamic range without employing any premeasurement and presents levels in randomized order. The procedure has been named "Oldenburg-ACALOS" (Oldenburg-Adaptive CAtegorical LOudness Scaling). It was evaluated using repeated measurements with ten subjects with normal hearing and ten subjects with sensorineural hearing impairment. The results of this investigation revealed that the adaptive procedure provides greater reliability, while being more time efficient than a reference procedure that uses constant stimuli.     

An effect of temporal asymmetry on loudness

A set of experiments was conducted to examine the loudness of sounds with temporally asymmetric amplitude envelopes. Envelopes were generated with fast-attack/slow-decay characteristics to produce F-S (or "fast-slow") stimuli, while temporally reversed versions of these same envelopes produced corresponding S-F ("slow-fast") stimuli. For sinusoidal (330-6000 Hz) and broadband noise carriers, S-F stimuli were louder than F-S stimuli of equal energy. The magnitude of this effect was sensitive to stimulus order, with the largest differences between F-S and S-F loudness occurring after exposure to a preceding F-S stimulus. These results are not compatible with automatic gain control, power-spectrum models of loudness, or predictions obtained using the auditory image model [Patterson et al., J. Acoust. Soc. Am. 98, 1890-1894 (1995)]. Rather, they are comparable to phenomena of perceptual constancy, and may be related to the parsing of auditory input into direct and reverberant sound.     

An introduction to the Cassini-Huygens mission

Summary Cassini-Huygens, a large mission sponsored by NASA and ESA, will fully explore the Saturnian system at the beginning of next century. In view of its great scientific interest and the involvement of the European Space Agency and the Agenzia Spaziale Italiana,Il Nuovo Cimento is publishing five papers dealing with the main features of the mission. This is a general introduction, with some attention to the planning of interplanetary space mission. Paper presented at the V Cosmic Physics National Conference, S. Miniato, November 27–30, 1990.     

An introduction to on-shell recursion relations

This article provides an introduction to on-shell recursion relations for calculations of tree-level amplitudes. Starting with the basics, such as spinor notations and color decompositions, we expose analytic properties of gauge-boson amplitudes, BCFW-deformations, the large z-behavior of amplitudes, and on-shell recursion relations of gluons. We discuss further developments of on-shell recursion relations, including generalization to other quantum field theories, supersymmetric theories in particular, recursion relations for off-shell currents, recursion relation with nonzero boundary contributions, bonus relations, relations for rational parts of one-loop amplitudes, recursion relations in 3D and a proof of CSW rules. Finally, we present samples of applications, including solutions of split helicity amplitudes and of N = 4 SYM theories, consequences of consistent conditions under recursion relation, Kleiss-Kuijf (KK) and Bern-Carrasco-Johansson (BCJ) relations for color-ordered gluon tree amplitudes, Kawai-Lewellen-Tye (KLT) relations.