Semi-parametric estimation without searching in function space: application toin vivometabolite quantitation

Reconstructions of asymmetric objects computed by electron tomography are distorted due to the absence of information, usually in an angular range from 60 to 90°, which produces a “missing wedge” in Fourier space. These distortions often interfere with the interpretation of results and thus limit biological ultrastructural information which can be obtained. We have attempted to use the Method of Projections Onto Convex Sets (POCS) for restoring the missing information. In POCS, use is made of the fact that known constraints such as positivity, spatial boundedness or an upper energy bound define convex sets in function space. Enforcement of such constraints takes place by iterating a sequence of function-space projections, starting from the original reconstruction, onto the convex sets, until a function in the intersection of all sets is found. First applications of this technique in the field of electron microscopy have been promising.To test POCS on experimental data, we have artificially reduced the range of an existing projection set of a selectively stained Golgi apparatus from ±60° to ±50°, and computed the reconstruction from the reduced set (51 projections). The specimen was prepared from a bull frog spinal ganglion as described by Lindsey and Ellisman and imaged in the high-voltage electron microscope.

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Finite-order Integration Weights Can be Dangerous

Computational Methods in Applied Mathematics ◽

10.2478/cmam-2007-0015 ◽

2007 ◽

Vol 7 (3) ◽

pp. 239-254 ◽

Cited By ~ 3

Author(s):

I.H. Sloan

Keyword(s):

Function Space ◽

Finite Order ◽

Small Subset ◽

Worst Case ◽

Integration Rule ◽

Dimensional Lattice ◽

3 Dimensional ◽

Sum Of Functions ◽

Integration Rules

Abstract Finite-order weights have been introduced in recent years to describe the often occurring situation that multivariate integrands can be approximated by a sum of functions each depending only on a small subset of the variables. The aim of this paper is to demonstrate the danger of relying on this structure when designing lattice integration rules, if the true integrand has components lying outside the assumed finiteorder function space. It does this by proving, for weights of order two, the existence of 3-dimensional lattice integration rules for which the worst case error is of order O(N¯½), where N is the number of points, yet for which there exists a smooth 3- dimensional integrand for which the integration rule does not converge.

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On the dynamic response and collapse of slender guyed booms for space application

10.2514/6.1983-821 ◽

1983 ◽

Author(s):

J. HOUSNER ◽

W. BELVIN

Keyword(s):

Dynamic Response ◽

Space Application

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A Function Space Approach to Spectral Related Problems

Journal of Computer and Mathematical Sciences ◽

10.29055/jcms/1107 ◽

2019 ◽

Vol 10 (6) ◽

pp. 1220-1222

Author(s):

T. Venkatesh ◽

Karuna Samaje

Keyword(s):

Function Space ◽

Space Approach

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Validity-Study of Commercial Semiconductor with TO-18 Package for Space Application by PIND Test

ISTFA 2013: Conference Proceedings from the 39th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2013p0523 ◽

2013 ◽

Author(s):

Yusuke Nakatake ◽

Makoto Okabe ◽

Shota Sato

Keyword(s):

Industrial Applications ◽

Validity Study ◽

Space Application ◽

Noise Detection ◽

Foreign Material ◽

Contamination Control ◽

X Ray ◽

Impact Noise ◽

Report Analysis ◽

Foreign Materials

Abstract In this paper, we carried out PIND (Particle Impact Noise Detection) test and X-ray inspection of a transistor in a TO-18 package for commercial and industrial applications. From our evaluation results, we explain the validity of the PIND test by comparing PIND test and X-ray inspection results. We make clear that PIND test is able to detect internal foreign material that may be transparent to X-ray inspection. In addition, we report analysis results of internal foreign materials from defective devices. This matter suggests that a problem is contamination control in the manufacturing process, most likely the sealing process.

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Robust Test Method of TSOP PEMs for Space Application

ISTFA 2019: Conference Proceedings from the 45th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2019p0513 ◽

2019 ◽

Author(s):

Yasunobu Iwai ◽

Koichi Shinozaki ◽

Daiki Tanaka

Keyword(s):

Evaluation Method ◽

Low Cost ◽

Reliability Evaluation ◽

Test Method ◽

Thermal Shock Test ◽

Space Application ◽

Space Applications ◽

Limit Test ◽

Long Time ◽

Short Time

Abstract Compared with space parts, consumer parts are highly functional, low cost, compact and lightweight. Therefore, their increased usage in space applications is expected. Prior testing and evaluation on space applicability are necessary because consumer parts do not have quality guarantees for space application [1]. However, in the conventional reliability evaluation method, the test takes a long time, and the problem is that the robustness of the target sample can’t be evaluated in a short time. In this report, we apply to the latest TSOP PEM (Thin Small Outline Package Plastic Encapsulated Microcircuit) an evaluation method that combines preconditioning and HALT (Highly Accelerated Limit Test), which is a test method that causes failures in a short time under very severe environmental conditions. We show that this method can evaluate the robustness of TSOP PEMs including solder connections in a short time. In addition, the validity of this evaluation method for TSOP PEM is shown by comparing with the evaluation results of thermal shock test and life test, which are conventional reliability evaluation methods.

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Pulsed Laser Stimulation Coupled with Optical Failure Analysis Technique—A Methodology to Help Space Application Electrical Designers

ISTFA 2015: Conference Proceedings from the 41st International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2015p0025 ◽

2015 ◽

Author(s):

G. Bascoul ◽

K. Sanchez ◽

G. Perez ◽

F. Bezerra ◽

H. Chauvin

Keyword(s):

Heavy Ions ◽

Pulsed Laser ◽

Radiation Sensitivity ◽

Radiation Environment ◽

Physical Analysis ◽

Space Application ◽

Voltage Converter ◽

Industrial Laboratory ◽

Sensitivity Evaluation ◽

Analysis Technique

Abstract Pulsed laser for radiation sensitivity evaluation has become a common tool used in research and industrial laboratory. This paper aims to highlight an approach to understand weaknesses of a component under radiation environment using a short pulsed width laser beam coupled to thermography technique, heavy ions test inputs and physical analysis. This paper is based on a study of a PWM device embedded on voltage converter.

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