Distortion evaluation method for the progressive addition lens–eye system

Nowadays, progressive addition lenses are widely applied to correct people’s vision disorders, but the design and machining of progressive addition lenses are still difficult. Generally, a progressive addition lens has a freeform front surface and a spherical back surface. In this article, the design of the front surface was simplified as a minimization problem of a functional, and the solution was obtained directly using a variational-difference method. After solving this problem, the description of the surface was discussed, and an evaluation method was proposed to analyze the fitting accuracy of Zernike polynomial method and B-spline interpolation method with different degrees. As a result, the progressive addition lens surface was constructed by the method with smaller fitting error. Moreover, a new generation algorithm of entrance parameters for tool path generation was put forward, which can reduce the interpolation error. The experimental results indicate that the design method was feasible and the machined surface quality was satisfactory using the proposed algorithm.

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Evaluation method for imaging plate resolution by means of phase contrast transfer function

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100139688 ◽

1995 ◽

Vol 53 ◽

pp. 662-663 ◽

Cited By ~ 1

Author(s):

T. Oikawa ◽

H. Kosugi ◽

F. Hosokawa ◽

D. Shindo ◽

M. Kersker

Keyword(s):

Transfer Function ◽

Phase Contrast ◽

Evaluation Method ◽

Amorphous Film ◽

Imaging Plate ◽

X Rays ◽

Special Shape ◽

Contrast Transfer Function ◽

Contrast Image ◽

Specimen Shape

Evaluation of the resolution of the Imaging Plate (IP) has been attempted by some methods. An evaluation method for IP resolution, which is not influenced by hard X-rays at higher accelerating voltages, was proposed previously by the present authors. This method, however, requires truoblesome experimental preperations partly because specially synthesized hematite was used as a specimen, and partly because a special shape of the specimen was used as a standard image. In this paper, a convenient evaluation method which is not infuenced by the specimen shape and image direction, is newly proposed. In this method, phase contrast images of thin amorphous film are used.Several diffraction rings are obtained by the Fourier transformation of a phase contrast image of thin amorphous film, taken at a large under focus. The rings show the spatial-frequency spectrum corresponding to the phase contrast transfer function (PCTF). The envelope function is obtained by connecting the peak intensities of the rings. The evelope function is offten used for evaluation of the instrument, because the function shows the performance of the electron microscope (EM).

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Combining Values

Guides Newsletter ◽

10.1001/amaguidesnewsletters.2002.marapr01 ◽

2002 ◽

Vol 7 (2) ◽

pp. 1-4, 12 ◽

Cited By ~ 1

Author(s):

Christopher R. Brigham

Keyword(s):

Lower Extremity ◽

Upper Extremity ◽

Evaluation Method ◽

Proximal Phalanx ◽

Common Error ◽

The Third ◽

Whole Person ◽

Impairment Ratings ◽

Upper Extremity Impairment ◽

The Individual

Abstract To account for the effects of multiple impairments, evaluating physicians must provide a summary value that combines multiple impairments so the whole person impairment is equal to or less than the sum of all the individual impairment values. A common error is to add values that should be combined and typically results in an inflated rating. The Combined Values Chart in the AMA Guides to the Evaluation of Permanent Impairment, Fifth Edition, includes instructions that guide physicians about combining impairment ratings. For example, impairment values within a region generally are combined and converted to a whole person permanent impairment before combination with the results from other regions (exceptions include certain impairments of the spine and extremities). When they combine three or more values, physicians should select and combine the two lowest values; this value is combined with the third value to yield the total value. Upper extremity impairment ratings are combined based on the principle that a second and each succeeding impairment applies not to the whole unit (eg, whole finger) but only to the part that remains (eg, proximal phalanx). Physicians who combine lower extremity impairments usually use only one evaluation method, but, if more than one method is used, the physician should use the Combined Values Chart.

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SEBEW - An evaluation method for user interfaces of command and control systems

PsycEXTRA Dataset ◽

10.1037/e576892012-013 ◽

2003 ◽

Author(s):

Heino Widdel ◽

Florian Motz

Keyword(s):

Control Systems ◽

User Interfaces ◽

Evaluation Method ◽

Command And Control ◽

And Control

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Functional Evaluation of Integrated Passenger Transportation Hub Based on Fuzzy Comprehensive Evaluation Method

CICTP 2020 ◽

10.1061/9780784483053.225 ◽

2020 ◽

Author(s):

Jianyou Zhao ◽

Yi Li ◽

Yuntao Ye

Keyword(s):

Evaluation Method ◽

Comprehensive Evaluation ◽

Fuzzy Comprehensive Evaluation ◽

Functional Evaluation ◽

Fuzzy Comprehensive Evaluation Method ◽

Comprehensive Evaluation Method ◽

Passenger Transportation

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Study on Post Evaluation Method of Highway Asphalt Pavement Preventive Maintenance Engineering

CICTP 2020 ◽

10.1061/9780784483053.104 ◽

2020 ◽

Author(s):

Jie Zhu ◽

Zhi Chai ◽

Shujie Wang ◽

Qianrong Lei

Keyword(s):

Preventive Maintenance ◽

Evaluation Method ◽

Asphalt Pavement ◽

Post Evaluation ◽

Maintenance Engineering

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A fuzzy evaluation method of road vehicle automatic weighing instrument in dynamic force metrological performance

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209455 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 1365-1372

Author(s):

Xiaohui Mao ◽

Liping Fei ◽

Xianping Shang ◽

Jie Chen ◽

Zhihao Zhao

Keyword(s):

Evaluation Method ◽

Comprehensive Evaluation ◽

Evaluation Model ◽

Dynamic Performance ◽

Dynamic Force ◽

Fuzzy Evaluation ◽

Road Vehicle ◽

Evaluation Standard ◽

The Road ◽

Metrological Performance

The measurement performance of road vehicle automatic weighing instrument installed on highways is directly related to the safety of roads and bridges. The fuzzy number indicates that the uncertain quantization problem has obvious advantages. By analyzing the factors affecting the metrological performance of the road vehicle automatic weighing instrument, combined with the fuzzy mathematics theory, the weight evaluation model of the dynamic performance evaluation of the road vehicle automatic weighing instrument is proposed. The factors of measurement performance are summarized and calculated, and the comprehensive evaluation standard of the metering performance of the weighing equipment is obtained, so as to realize the quantifiable analysis and evaluation of the metering performance of the dynamic road vehicle automatic weighing instrument in use, and provide data reference for adopting a more scientific measurement supervision method.

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Simply supported FPEDs connected by springs for broadband energy harvesting

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209323 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 201-210

Author(s):

Yoshikazu Tanaka ◽

Satoru Odake ◽

Jun Miyake ◽

Hidemi Mutsuda ◽

Atanas A. Popov ◽

...

Keyword(s):

Energy Harvesting ◽

Evaluation Method ◽

Energy Harvester ◽

Vibrational Energy ◽

Functional Materials ◽

Vibration Energy ◽

Theoretical Evaluation ◽

Vibration Energy Harvester ◽

Polyvinylidene Difluoride ◽

Simply Supported

Energy harvesting methods that use functional materials have attracted interest because they can take advantage of an abundant but underutilized energy source. Most vibration energy harvester designs operate most effectively around their resonant frequency. However, in practice, the frequency band for ambient vibrational energy is typically broad. The development of technologies for broadband energy harvesting is therefore desirable. The authors previously proposed an energy harvester, called a flexible piezoelectric device (FPED), that consists of a piezoelectric film (polyvinylidene difluoride) and a soft material, such as silicon rubber or polyethylene terephthalate. The authors also proposed a system based on FPEDs for broadband energy harvesting. The system consisted of cantilevered FPEDs, with each FPED connected via a spring. Simply supported FPEDs also have potential for broadband energy harvesting, and here, a theoretical evaluation method is proposed for such a system. Experiments are conducted to validate the derived model.

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