Pitch identification of simultaneous diotic and dichotic two-tone complexes

This study examines subjects' ability to recognize the pitches of two missing fundamentals in two simultaneous two-tone complexes whose partials are distributed in various ways between subjects' ears. The data show that identification performance is affected on different levels. Limited frequency resolution in the peripheral auditory system can degrade performance, but only if none of the four stimulus partials is aurally resolved. Identification performance is only weakly dependent on the manner of distributing partials between the ears. In some cases it was found that, probably at a very central level (e.g., attention), the identification processes of both simultaneous pitches interfere with one another. Some subjects are more likely to identify the pitch of one two-tone complex when the harmonic order of the other complex is higher than when this harmonic order is lower. Finally, some subjects tend to hear the complex tones analytically, i.e., perceive pitches of single partials instead of the missing fundamentals for some distribution of partials between the ears.     

信道编码中交织器的盲识别

研究了分组交织、卷积交织和螺旋交织三种交织器参数盲识别模型,结合秩准则算法与高斯约当消元法,对于各交织器的交织深度、交织宽度、交织偏差、交织步长等参数的盲识别进行了分析,并进一步基于解交织理论和软信息,提出了一种盲解交织的通用方法,提高了算法的实用性和可行性,使其更适用于实际信道。通过仿真实验,验证了在较高误码率下三种交织参数盲识别算法的有效性和抗噪能力。     

Combined surface-focused acoustic microscopy in transmission and scanning ultrasonic holography

Employment of ultrasound techniques in nondestructive testing may require identification of the acoustic modes contributing to imaging. Such identification can be achieved, with some restrictions, by time-of-flight analysis. Another approach is acoustic holography that reveals the propagation properties of any selected mode. In anisotropic media, the propagation features are distinct and allow for a reliable classification of the selected mode. Both techniques were applied for classification of bonded, disbonded, and weakly bonded areas in directly bonded semiconductor wafers.     

Quantum system identification

The aim of quantum system identification is to estimate the ingredients inside a black box, in which some quantum-mechanical unitary process takes place, by just looking at its input-output behavior. Here we establish a basic and general framework for quantum system identification, that allows us to classify how much knowledge about the quantum system is attainable, in principle, from a given experimental setup. We show that controllable closed quantum systems can be estimated up to unitary conjugation. Prior knowledge on some elements of the black box helps the system identification. We present an example in which a Bell measurement is more efficient to identify the system. When the topology of the system is known, the framework enables us to establish a general criterion for the estimability of the coupling constants in its Hamiltonian.     

Recent applications of EPR and spin trapping to sonochemical studies of organic liquids and aqueous solutions

In this paper we review some of our recent applications of the EPR spin trapping technique to sonochemical studies which include identification of radicals formed in organic liquids and aqueous mixtures of organic liquids, estimation of temperatures of sonochemical regions in mixtures of deuterated and non-deuterated solvents, and the identification of reactive radical intermediates which may play a role in synergistic cell killing by ultrasound and drugs (sonodynamic interactions).     

无源射频识别系统中的雷达截面分析与计算

基于无源射频识别技术原理和天线散射理论,导出了不同负载情况下的雷达截面计算方法,并结合雷达截面和电磁传播环境分析了无源射频识别系统的识别距离.通过测量标签天线不同负载情况下的反向散射功率,再结合该计算方法,从而得出雷达截面.理论分析与实验测量结果保持一致.研究结果对优化无源射频识别系统的标签性能有益. 关键词： 射频识别 天线 雷达截面 识别距离     

基于P向量与三角形内切圆的星图识别算法

为了减少导航星表的存储容量和提高星图识别的成功率,提出了一种将P向量与三角形内切圆相结合的快速全天自主星图识别算法.该算法在构造导航星表过程中,从天文星表中挑选出满足要求的导航星并对其编号,以构造的P向量值、导航三角形内切圆半径R及导航三角形的第三条边为特征量构造导航子星表;在识别过程中,找出一定误差门限内,满足P向量...     

One application of Bouc's model for non-linear hysteresis

A non-linear two parametric model introduced by R. Bouc is used to describe the hysteretic loops obtained from experiments on stranded cables. The procedure for identification of model parameters is given and the physical meaning of parameters is discussed. An application to two types of Stockbridge dampers shows sufficient accuracy of the model and the identification procedure within some range of system and load parameters.     

一维纳米材料的本征拉曼谱和‘反常’的拉曼光谱特征

本文将报告对几个典型的一维纳米材料的本征拉曼光谱的鉴认和应用 ,以及对它们的‘反常’拉曼特征及其起源和本质的研究结果     

Christoffel symbols and inertia in flat space-time theory

A necessary and sufficient criterion of inertia is presented, for the flat space-time theory of general frames of reference, in terms of the vanishing of some typical components of the affine connection pertaining to curvilinear coordinate systems. The physical identification of inertial forces thus arises in the context of the special theory of relativity.     

A FREQUENCY-DOMAIN METHOD OF STRUCTURAL DAMAGE IDENTIFICATION FORMULATED FROM THE DYNAMIC STIFFNESS EQUATION OF MOTION

This paper introduces a frequency-domain method of structural damage identification. It is formulated in a general form from the dynamic stiffness equation of motion for a structure and then applied to a beam structure. Only the dynamic stiffness matrix for the intact state appears in the final form of the damage identification algorithm as the structure model. The appealing features of the present damage identification method are: (1) it requires only the frequency response functions experimentally measured from the damaged structure as the input data, and (2) it can locate and quantify many local damages at the same time. The feasibility of the present damage identification method is tested through some numerically simulated damage identification analyses and then experimental verification is conducted for a cantilevered beam with damage caused by introducing three slots.     

Chaos and localization in coupled quartic oscillators

We discuss some of the models for eigenfunction localization in Hamiltonian systems. In particular, we review some of our work on classical parametric scaling of orbits and identification of localized states in a two-dimensional quartic oscillator system which is deep in the classically chaotic region. We show that visual methods are a necessary complement to quantitative methods based on information entropies. Our preliminary results indicate that the periodic orbit stability determines the degree of localization in a class of states, even when the stable regions are of negligible measure.     

Aircraft noise-monitoring according to ISO 20906. Evaluation of uncertainty derived from the classification and identification of aircraft noise events

Noise monitoring continues to be one of the most important tools in noise management around airports, since noise pollution is a serious problem for the surrounding communities. The monitoring units must be reliable and precise in order to ensure the quality of the results provided. As a previous step to achieve this, it is necessary to make an estimation of the uncertainty of the results, taking into account the contribution of every single element in the measurement chain. Among other contributions to uncertainty as listed in ISO 20906, the events marking system has an influence on the measurement results on two different levels: the first one, derives from the human factors affecting the event detection while the second one derives from the error rates of the classification–identification chain. In this paper, the focus is set on the latter, which has been called identification uncertainty. A model has been defined for its estimation and a methodology of application has been described. The results have been calculated for some specific situations in order to clarify the methodology and to have some estimations of the value of this contribution to uncertainty. Just for a location very close to the airport (aircraft events range over 20 dB), this contribution to uncertainty can be up to 0.5 dB when simple detection techniques are used, and can be reduced to approximately 0.1 dB when radar tracking is used to enhance the identification task. In more complex acoustic environments, the identification uncertainty can increase up to 5 dB (or more) in the absence of accurate classification/identification tools.     

傅里叶红外(FT-IR)差谱技术在复合材料分析中的应用

用FT-IR差谱技术对几种类型的复合材料进行定性分析，尝试能有效地找出影响分析结果的某些因素，从而提高应用该技术分析的效果。通过实例表明，该技术是一种值得推荐的快速鉴定方法。     

不同产地葛根红外光谱的三级鉴定

运用红外光谱法和二维相关光谱技术对天津八仙山、湖南壶瓶山、重庆金佛山三种产地的葛根样本进行了分析鉴定。分析结果表明：不同产地葛根的红外光谱(一级鉴定)和二阶导数谱(二级鉴定)具有一定的相似度,与淀粉和葛根素的谱图比对,三个样本都富含淀粉和一定量的葛根素,不同的是天津葛根在1 048 cm-1波数处的最强峰与淀粉在986 cm-1处的最强峰相差了62个波数,说明淀粉的含量较低,而在891,835和797 cm-1的特征峰与葛根素的指纹特征更一致,可见葛根素的含量要高一些。在二维相关谱图(三级鉴定)上,三种产地的葛根形成的峰簇的位置和数量不同,可以进行产地的鉴别。结果表明,对于不同产地葛根的分析,红外光谱法的三级鉴定是一种有效和快速的检测方法。     

IDENTIFICATION OF MULTIPLE FAULTS IN ROTOR SYSTEMS

Many papers are available in the literature about identification of faults in rotor systems. However, they generally deal only with a single fault, usually an unbalance. Instead, in real machines, the case of multiple faults is quite common: the simultaneous presence of a bow (due to several different causes) and an unbalance or a coupling misalignment occurs often in rotor systems. In this paper, a model-based identification method for multiple faults is presented. The method requires the definition of the models of the elements that compose the system, i.e., the rotor, the bearings and the foundation, as well as the models of the faults, which can be represented by harmonic components of equivalent force or moment systems. The identification of multiple faults is made by a least-squares fitting approach in the frequency domain, by means of the minimization of a multi-dimensional residual between the vibrations in some measuring planes on the machine and the calculated vibrations due to the acting faults. Some numerical applications are reported for two simultaneous faults and some experimental results obtained on a test-rig are used to validate the identification procedure. The accuracy and limits of the proposed procedure have been evaluated.     

Mathematical modeling of randomness and fuzziness phenomena in scientific studies. II. Applications

This paper considers some elements of the optimal fuzzy decision theory that are similar to the optimal statistical decision theory, in particular, the theory of optimal fuzzy identification and optimal fuzzy hypothesis testing, such as Neyman–Pearson statistical hypothesis testing and optimal fuzzy estimation along with a sequential fuzzy identification algorithm similar to the Wald sequential statistical criterion. Some elements of the fuzzy measuring and computing transducer theory and its applications in the problems of the analysis and interpretation of measurement experiment data are given.     

Template identification technology of nuclear warheads and components

Template identification technology （TIT） is designed for the scenarios where a batch of disarmed nuclear weapons or components would be dismantled to observe a nuclear disarmament treaty. The core function played by the TIT is to make a judgment on whether the verified item belongs to a certain kind of nuclear weapons or component （NW/NC） or to which kind the verified item belongs. This paper analyses the functions played by the TIT in the process of NW/NC dismantlement, and proposes that two phases would be followed when applying the TIT： firstly to establish NW/NC templates with a sample of size n drawn from a certain kind of disarmament NW; secondly to authenticate NW/NC by means of the TIT. This paper also expatiates some terms related to the concept of the TIT and investigates on the development status of NW/NC TIT based on radiation signatures. The study concludes that the design of template structure is crucial to the establishment of an effective TIT and that starting from different research angles and aiming at the same goal of classification different template structures and corresponding template identification methods can be built up to meet specific identification requirements.     

Characterisation of phases in nanostructured, multilayered titanium alloys by analytical and high-resolution electron microscopy

Surface processing of a Ti-6Al-4V alloy led to a complex multilayered microstructure containing several phases of the Ni-Ti-P-Al-O system, which improves the mechanical and tribological surface properties. The microstructure, chemical and phase compositions of the hard layer formed on the surface were investigated by LM, XRD, SEM as well as analytical/high-resolution TEM, STEM, EDS, electron diffraction and FIB. Phase identification based on electron diffraction, HRTEM and EDS microanalysis revealed the presence of several binary and ternary phases in the system Ti-Ni-P, sometimes with partial substitution of Ti by Al. However some phases, mainly nanoparticles, still remain not identified satisfactorily. Electron microscopy techniques used for identification of phases present in surface multilayers and some practical limits to their routine application are reminded here.