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1.
Ancient musical instruments can tell us much about the way composers of the past centuries wrote their music. Indeed, the sound and playing characteristics of historical instruments are often very different from those of the instruments we are used to. For example, in the case of the Viennese piano actions used by Mozart and his contemporaries, the so-called “escapement height” largely conditions the response of the instrument to the pianist’s touch. In this contribution, we aim to define how the Viennese action behaves when the escapement height, usually tuned by piano technicians, is changed.To do this, a multibody model containing the frame, the key, the hammer, the pawl, and the string has been developed. This paper describes how the model has been carried out; a special focus is put on the detection of the intermittent contacts between bodies, which may look easy in the real action, but is rather complex to model. The model is compared with high-speed imaging data and a parametric study of the escapement height is performed by adjusting the rest position of the pawl. The high sensitivity of this regulation is revealed as a shift of 1 mm of the pawl seems to induce a displacement of the escapement height of 20 mm. It is also shown that a strong but linear decrease of the maximal force between the hammer and the string appears when the escapement height increases.  相似文献   

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Display technologies are used in various industries. However, few studies on color vision testing using self‐luminous displays are reported. In this study, a screen‐based color vision test, termed the digital color vision test (DCVT), is developed on a color‐calibrated monitor. A control bar is adjusted by the observer to build just noticeable chromatic difference ellipses in CIE u′v′ chromaticity diagram, which indicate the capabilities of subjects' color visions. Ten color‐normal observers and 13 deutan observers participated in the psychophysical experiments. The observers also performed the other two typical diagnostic tests (D‐15 and anomaloscope). Results from the experiment using the adjustment psychophysical method for digital quantification of deutan color vision defects are presented. It is found that the diagnosis accuracy of the DCVT is approximately equivalent to those of D‐15 and anomaloscope tests.  相似文献   

4.
Sandmark is a tool that measures the effectiveness of software-based methods for protecting software from piracy, tampering, and reverse engineering. The Sandmark team's goal is to develop techniques that will let users determine empirically which algorithms have the least performance overhead and the highest resilience to attacks.  相似文献   

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Most active optical range sensors record, simultaneously with the range image, the amount of light reflected at each measured surface location: this information forms what is called a range intensity image, also known as a reflectance image. This paper proposes a method that uses this type of image for the correction of the color information of a textured 3D model. This color information is usually obtained from color images acquired using a digital camera. The lighting condition for the color images are usually not controlled, thus this color information may not be accurate. On the other hand, the illumination condition for the range intensity image is known since it is obtained from a controlled lighting and observation configuration, as required for the purpose of active optical range measurement. The paper describes a method for combining the two sources of information, towards the goal of compensating for a reference range intensity image is first obtained by considering factors such as sensor properties, or distance and relative surface orientation of the measured surface. The color image of the corresponding surface portion is then corrected using this reference range intensity image. A B-spline interpolation technique is applied to reduce the noise of range intensity images. Finally, a method for the estimation of the illumination color is applied to compensate for the light source color. Experiments show the effectiveness of the correction method using range intensity images.  相似文献   

7.
ABSTRACT

Visual representations of data introduce several possible challenges for the human visual perception system in perceiving brightness levels. Overcoming these challenges might be simplified by adding sound to the representation. This is called sonification. As sonification provides additional information to the visual information, sonification could be useful in supporting the visual perception. In the present study, usefulness (in terms of accuracy and response time) of sonification was investigated with an interactive sonification test. In the test, participants were asked to identify the highest brightness level in a monochrome visual representation. The task was performed in four conditions, one with no sonification and three with different sonification settings. The results show that sonification is useful, as measured by higher task accuracy, and that the participant's musicality facilitates the use of sonification with better performance when sonification was used. The results were also supported by subjective measurements, where participants reported an experienced benefit of sonification.  相似文献   

8.
Characteristics of tongue pose the most important information for Traditional Chinese Medicine diagnosis. So far, extensive studies have been made on extracting tongue surface features, but rarely refer to sublingual vein that is also diagnostically important. This paper focuses on establishing a feature quantification framework for the inspection of sublingual veins, composed of two parts: the segmentation of sublingual veins and the feature quantification of them. Pixel-based sublingual vein segmentation algorithm and adaptive sublingual vein segmentation algorithm for color sublingual images with visible contrast and low contrast are proposed respectively. The experiments prove that the proposed algorithms perform well on the segmentation of sublingual veins from color sublingual images with both visible contrast and low contrast. A chromatic system in conformity with diagnostic standard of tongue diagnosis is established to characterize the chromatic feature of sublingual veins. Experimental results reveal that the breadth and chromatic features quantified by the proposed framework are properly consistent with the diagnostic standard summarized by tongue diagnosis.  相似文献   

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Multimedia Tools and Applications - The color image enhancement algorithm proposed here yields an improvement of the image data that suppresses undesired distortions or enhances some image features...  相似文献   

11.
User behavior is significantly influenced by the surrounding environment. Especially complex and dynamically changing environments (like mobile environment) are represented by a wide variety of extraneous variables, which influence the user behavior in an unpredictable and mostly uncontrolled way. For researchers, it is challenging to measure and analyze the user behavior in such environments. We introduce a complex tool—the IVE tool—which provides a unique way of context visualization and synchronization of measured data of various kinds. Thanks to this tool it is possible to efficiently evaluate data acquired during complex usability tests in a mobile environment. The functionality of this tool is demonstrated on the use case “Navigation of visually impaired users in the building with support of a navigation system called NaviTerier.” During the experiment, we focused on collection and analysis of data that may show user stress and which may influence his/her ability to navigate. We analyzed objective data like Galvanic Skin Response parameter (GSR), Heart Rate Variability parameters (HRV) and audio video recordings and also subjective data like the user’s subjective stress feeling and observation of the user’s behavior.  相似文献   

12.
This paper presents a software simulation package of the entire X-ray projection radiography process including beam generation, absorber structure and composition, irradiation set up, radiation transport through the absorbing medium, image formation and dose calculation. Phantoms are created as composite objects from geometrical or voxelized primitives and can be subjected to simulated irradiation process. The acquired projection images represent the two-dimensional spatial distribution of the energy absorbed in the detector and are formed at any geometry, taking into account energy spectrum, beam geometry and detector response. This software tool is the evolution of a previously presented system, with new functionalities, user interface and an expanded range of applications. This has been achieved mainly by the use of combinatorial geometry for phantom design and the implementation of a Monte Carlo code for the simulation of the radiation interaction at the absorber and the detector.  相似文献   

13.
深度学习能自动从大样本数据中学习获得优良的特征表达,有效提升各种机器学习任务的性能,已广泛应用于信号处理、计算机视觉和自然语言处理等诸多领域。基于深度学习的医学影像智能计算是目前智慧医疗领域的研究热点,其中深度学习方法已经应用于医学影像处理、分析的全流程。由于医学影像内在的特殊性、复杂性,特别是考虑到医学影像领域普遍存在的小样本问题,相关学习任务和应用场景对深度学习方法提出了新要求。本文以临床常用的X射线、超声、计算机断层扫描和磁共振等4种影像为例,对深度学习在医学影像中的应用现状进行综述,特别面向图像重建、病灶检测、图像分割、图像配准和计算机辅助诊断这5大任务的主要深度学习方法的进展进行介绍,并对发展趋势进行展望。  相似文献   

14.
The increasing prevalence of multimedia and research data generated by scientific work affords an opportunity to reformulate the idea of a scientific article from the traditional static document, or even one with links to supplemental material in remote databases, to a self-contained, multimedia-rich interactive publication. This paper describes our concept of such a document, and the design of tools for authoring (Forge) and visualization/analysis (Panorama). They are platform-independent applications written in Java, and developed in Eclipse1 using its Rich Client Platform (RCP) framework. Both applications operate on PDF files with links to XML files that define the media type, location, and action to be performed. We also briefly cite the challenges posed by the potentially large size of interactive publications, the need for evaluating their value to improved comprehension and learning, and the need for their long-term preservation by the National Library of Medicine and other libraries.  相似文献   

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Microsystem Technologies - Because today a physician has no reliable tool to monitor a medical needle, when he inserted it into the human body, this paper deals with an instrumented medical needle,...  相似文献   

16.
It is an urgent task to hnplemeut a lot of expert systems to capture the valuable expertise ofexperienced doctors of traditional Chinese medicine.In order to meet the needs,a software tool isdeveloped.It features a unified diagnosis model,a specially designed knowledge representationlanguage and an efficient but effective inference engine.To implement an expert system,it isonly necessary to input the expert's knowledge expressed in knowledge representation languagewithout the design of any additional software.The time and effort required for implementing anexpert system are thus greatly saved.The software is very compact and can run onmicrocomputers e.g.IBM-PC/XT.Two traditional Chinese medical expert systems have beensuccessfully implemented with the tool.  相似文献   

17.
A 4th generation tool, called PRIST-2, is presented that has been designed as an interactive environment for the rapid prototyping of clinical applications in a large-scale Hospital Information System project. We adopted an SQL-based commercial Relational Data Base Management Systems (RDBMS) to guarantee portability on different hardware and operating systems. Relational databases, however, are characterized by a simple data structure and do not incorporate the application semantics required to ensure a high degree of data independence. To reach this goal, we propose an extension to the relational model, adding some of the main characteristics of the Object Oriented Data Base Management Systems (OODBMS) approach, such as "types" and "encapsulation".  相似文献   

18.
《微型机与应用》2015,(24):94-97
介绍了基于计算机视觉技术的直齿圆柱齿轮数字测量仪,阐述了仪器的运行原理、硬件组织结构和软件功能模块,提出了齿轮基本参数的测量算法。首先利用图像处理技术提取图像精确边缘,然后利用改进的随机Hough变换确定齿轮中心,最后计算齿轮基本参数并存储于数据库中。实验结果表明,该仪器测量精度高、速度快、操作简便、自动化程度高,对齿轮精密制造和机械传动具有重要意义。  相似文献   

19.
It is estimated that 37 million people worldwide suffer from blindness and 124 million people have impaired vision. While the relatively recently developed therapies, antivascular endothelial growth factor inhibitors for the treatment of age-related macular degeneration, and prostaglandin analogues for the treatment of glaucoma are beneficial for some patients, there are many individuals with sight-threatening diseases for whom no effective pharmacological therapy is available. For many of these diseases, the molecular mechanisms remain to be comprehensively elucidated, thus precluding the design of successful therapies against specific pathological targets. The current review summarises recent attempts to elucidate molecular mechanisms of ocular diseases, including diabetic retinal disease, age-related macular degeneration and inherited blindness using proteomic methodologies. A novel hypothesis can be generated from global protein expression analysis of disease tissue, which can then be addressed with cellular and in vivo functional studies. For example, the identification of extracellular carbonic anhydrase from the vitreous of diabetic retinopathy patients using MS based proteomics led to the elucidation of a new pathway involved in intraretinal edema, which could be inhibited by a number of agents targeting different proteins in this pathway in relevant animal models. The potential of protein biomarkers for diagnosis and the identification of novel disease mechanisms are also discussed.  相似文献   

20.

This article describes Soccer Server, a simulator of the game of soccer designed as a benchmark for evaluating multiagent systems and cooperative algorithms. In real life, successful soccer teams require many qualities, such as basic ball control skills, the ability to carry out strategies, and teamwork. We believe that simulating such behaviors is a significant challenge for computer science, artificial intelligence, and robotics technologies. It is to promote the development of such technologies, and to help define a new standard problem for research, that we have developed Soccer Server. We demonstrate the potential of Soccer Server by reporting an experiment that uses the system to compare the performance of a neural network architecture and a decision tree algorithm at learning the selection of soccer play plans. Other researchers using Soccer Server to investigate the nature of cooperative behavior in a multiagent environment will have the chance to assess their progress at RoboCup-97, an international competition of robotic soccer to be held in conjunction with IJCAI-97. Soccer Server has been chosen as the official server for this contest.  相似文献   

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