谈电表的选用

在电学实验中,测量方法上引起的误差,如伏安法测电源电动势与内阻的实验中电流计的内、外接所引起的相对误差,按理论计算应小于千分之一,而实际测量误差却是百分之几甚至更大．经研究与分析表明,电表本身的误差是引起测量结果误差的重要原因．本文通过对电表引用误差和准确度等级指标的探讨,谈如何正确选用电表,从而减小误差,达到正确测量的要求． 中专物理实验室用的直流电表通常是磁电式电表．选用电表要考虑安全因素和误差因素．安全因素即电表的读数不能超过示值范围．以下主要从误差因素谈如何选用电表．１电表的引用误差和准…     

用误差理论指导初中物理实验教学

用误差理论指导初中物理实验教学李升今（邯郸师专物理系）在指导初中物理实验时，有的教师认为初中物理实验原理简单、仪器简单、步骤简单、教据简单，在备课时不用误差理论去分析实验．用误差理论指导物理实验，既使初中物理实验也不容忽视，教师要做到居高临下，对实验...     

线性关系图像在实验探究中的应用

测得实验数据后进行数据处理，找出物理量之间的关系·，从而揭示物理规律，进行误差分析，是每个探究实验所必经的过程．用图像法处理、分析实验数据是物理实验探究中常用的方法．线性关系图像能形象直观地表达物理规律，有效地减少偶然误差对实验结果的影响，能方便地分析实验误差，获得未经测量或无法直接测量的物理量，在实验探究中有广泛的应用．     

选择正确的测量方法 提高测量灵敏度

选择正确的测量方法　提高测量灵敏度黄少鹏（安徽财贸学院物资贸易工程系蚌埠２３３０４１）一、测量灵敏度的意义物理实验中，测量值的精确度与测量灵敏度有着密切的关系．在实验中，如何提高测量灵敏度，减小测量误差，从而提高测量值的精确度是很重要的问题．测量灵敏...     

注重物理实验方法在医学中的应用

物理实验方法和操作技能是其它学科实验教学和科学研究的基础．医学院校培养的是卫生系统的医务人员，毕业后他们不仅要适应医院任职的需要，还要考虑他们今后发展的需要．因此，开设物理实验课的教学目的不仅要掌握进行实验的物理理论，更重要的是学习物理的实验方法，进行操作技能的训练，培养学生自己动手进行科学试验的能力，以适应科学技术不断进步和新时期医学建设的要求．但在医学院校中物理被当作一门十分次要的课程，物理实验更是次要中的次要．另一方面，实验内容多是测量某个物理量或单纯的验证性实验，与医学联系甚少，难唤起学…     

简析多次实验与多次测量的作用

物理实验的种类很多，其中测量性实验主要以测量为主；演示性实验主要以观察现象为主；验证性实验和探究性实验既有定性研究又有定量分析的成份，学生不仅要观察现象还要进行测量，并对测量结果分析概括．从物理研究的角度来看，必须经过多次实验才能总结某一结论或归纳某一规律．然而从编写教材与执教的方便考虑，现行课本上的实验在其具体过程中有一部分仅需做一次，但大部分仍安排三次以上，这些实验大都与测量有关．进行多次实验与进行多次测量的作用很多，现分类探讨．     

物理实验教学中不确定度的引入

介绍在传统物理实验教学中应用误差评定实验数据的弊端，应用不确定度评定测量结果的优点及在物理实验教学中引入不确定度的一种成功做法．     

近代物理实验教学改革初探

近代物理实验是物理专业学生的必修课．其中大部分实验在近代物理发展史上曾起过重要作用，对学生加深有关物理概念、规律的理解，活跃物理思想，掌握一些较先进的实验方法和技能以及培养科研能力有着重要的作用．和普通物理实验相比。它有设备先进且价格昂贵的特点．作为师范院校，在当今经费不足的情况下，怎样利用有限的设备，根据课程的要求培养出跨世纪的高质量人才，成为改革实验教学的重要课题．几年来。我系近代物理实验室同志不断改革．在许多方面进行了一些有益的探索．客观分析我系近代物理实验课情况，存在有如下问题：1．实验…     

重视物理实验培养学生创新思维能力

物理实验以其生动、直观和可操作性引导学生动手参与、掌握实验技能，学习科学的研究方法，培养学生的创新意识和创新能力．学好物理量的测量是做好物理实验的关键．     

全盲童也能窥探物质世界——盲童学校开设物理实验的介绍

介绍了日本的物理工作者，为了让全盲儿童也能得到物理实验的实践教育，他们从长期实验教学中摸索了许多有效的方法，使全盲学生也能做好物理实验，如自由落体实验、声速测量实验和光学实验等．     

Errors of neural networks

Errors of associative sampling and recognition in neural networks are determined by methods of the general theory of statistical solutions taking into account statistical variation of the input image, the correlation radius of the image, the number of neurons, and the number of images in the memory. The beta-distribution is proposed to be used as the statistics of image variations. The admissibility of the utilization of the distribution is tested by using temporal variations of real scenes as an example. The error in determining the coordinate is found for networks on the basis of optical correlators.     

Detecting Errors with Zero-Shot Learning

Error detection is a critical step in data cleaning. Most traditional error detection methods are based on rules and external information with high cost, especially when dealing with large-scaled data. Recently, with the advances of deep learning, some researchers focus their attention on learning the semantic distribution of data for error detection; however, the low error rate in real datasets makes it hard to collect negative samples for training supervised deep learning models. Most of the existing deep-learning-based error detection algorithms solve the class imbalance problem by data augmentation. Due to the inadequate sampling of negative samples, the features learned by those methods may be biased. In this paper, we propose an AEGAN (Auto-Encoder Generative Adversarial Network)-based deep learning model named SAT-GAN (Self-Attention Generative Adversarial Network) to detect errors in relational datasets. Combining the self-attention mechanism with the pre-trained language model, our model can capture semantic features of the dataset, specifically the functional dependency between attributes, so that no rules or constraints are needed for SAT-GAN to identify inconsistent data. For the lack of negative samples, we propose to train our model via zero-shot learning. As a clean-data tailored model, SAT-GAN tries to recognize error data as outliers by learning the latent features of clean data. In our evaluation, SAT-GAN achieves an average F1-score of 0.95 on five datasets, which yields at least 46.2% F1-score improvement over rule-based methods and outperforms state-of-the-art deep learning approaches in the absence of rules and negative samples.     

迈克耳孙干涉仪实验的误差探讨

根据迈克耳孙干涉仪的机械结构,分析了仪器误差的5个分量,确定了迈克耳孙干涉仪的仪器误差,分析了迈克耳孙干涉仪由于调节不当而产生的误差,提出了减小这类误差的方法,分析了振动对光波波长测量的影响,设计出了一种简易防震台,能明显减小震动的影响.     

Errors in two-point sound reproduction

This paper deals with the problem of reproducing two signals at two points in space by using two acoustic sources. While much is now known about the techniques available for the design of matrices of inverse filters that enable this objective to be achieved in practice, it is still the basic physics of the sound field produced that controls the effectiveness of such systems and which ultimately dictates their design. The basic physical processes involved in producing the cross-talk cancellation that enables the reproduction of the desired signals is revisited here by using a simple two source/two field point free field model. The singular value decomposition is used to identify those frequencies where the inversion problem becomes ill-conditioned and to explain physically the origin of the ill-conditioning. As observed previously, it is found that cross-talk cancellation becomes problematic when the path length difference between the two sources and one of the field points becomes equal to one half the acoustic wavelength. The ill-conditioned frequencies are also found to be associated with a limited spatial region of cross-talk cancellation and with large source outputs manifested in the time domain by responses of long duration.     

Errors in measurements of atomic masses

The methods of measuring the atomic masses of stable isotopes with high-resolution static and dynamic mass spectrometers are examined. The typical measurement errors characteristic of both classes of devices are indicated. The greatest difficulty arising in such experiments is taking account of the effect of stray electric fields on the parameters of the motion of two types of ions forming a mass doublet as well as determining and introducing corrections for the corresponding errors in the measured mass values. This effect could be especially important in measurements of wide mass doublets. A method similar to the one employed in direct measurements of the magnetic moment of the proton in terms of nuclear magnetons with a magnetic resonance mass spectrometer with a two-section ion source is suggested for taking into account the effect of the stray electric fields in atomic mass measurements. Zh. Tekh. Fiz. 67, 100–104 (February 1997)     

Sparse Density Estimation with Measurement Errors

This paper aims to estimate an unknown density of the data with measurement errors as a linear combination of functions from a dictionary. The main novelty is the proposal and investigation of the corrected sparse density estimator (CSDE). Inspired by the penalization approach, we propose the weighted Elastic-net penalized minimal ℓ2-distance method for sparse coefficients estimation, where the adaptive weights come from sharp concentration inequalities. The first-order conditions holding a high probability obtain the optimal weighted tuning parameters. Under local coherence or minimal eigenvalue assumptions, non-asymptotic oracle inequalities are derived. These theoretical results are transposed to obtain the support recovery with a high probability. Some numerical experiments for discrete and continuous distributions confirm the significant improvement obtained by our procedure when compared with other conventional approaches. Finally, the application is performed in a meteorology dataset. It shows that our method has potency and superiority in detecting multi-mode density shapes compared with other conventional approaches.     

Errors of observation and systematic errors

Methods of displaying results of repeated measurements, and choice of measures of scatter are considered. It is argued that graphical displays and a 50 per cent probability as basis for expression of errors are simpler than, and in many cases as useful as, any other method.

The importance of allowing for errors which affect to the same extent all measurements of a quantity throughout an investigation is emphasized, and a method of estimating that sort of systematic error is described and illustrated by an example.     

Assessment of the NM-Lines Sensitivity for Measurement Errors

In this work we investigate the sensitivity of the recently proposed NM-lines technique with respect to the error in the angle measurement in comparison with the conventional M-lines technique. The obtained results show that the NM-lines technique allows us to reduce the effect of the measurement errors and thus obtain better results for a given angular resolution.