Multiple Missing Information

1991 ◽  
pp. 101-111
Author(s):  
Stuart S. Nagel
Keyword(s):  
Author(s):  
Neng-Yu Zhang ◽  
Bruce F. McEwen ◽  
Joachim Frank

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.


2017 ◽  
Vol 32 (4) ◽  
pp. 61-80 ◽  
Author(s):  
Ellen E. Best ◽  
Jennifer Kahle Schafer

ABSTRACT Practitioners routinely note that new staff lack documentation skills, communication skills, and strong Excel skills. Further, new staff report critical-thinking, written and oral communication, teamwork, and project management skills deserve greater emphasis in Master of Accountancy programs. The AICPA's (2014) Model Tax Curriculum suggests that active learning approaches be used to enable students to build communication, critical-thinking, and interpersonal skills. This case uses a realistic corporate tax return preparation experience to address these criticisms by focusing on four main areas: time management, communication, research, and technical skills. The case is divided into two phases. In Phase 1, students review client information, generate requests from the client for missing information, keep a log of hours spent on the project, research ambiguous issues, meet with the project “senior” to obtain guidance, and prepare electronic work papers. In Phase 2, students incorporate feedback from the senior's review of their work papers to make corrections, prepare a corporate tax return, and create a client letter. Student feedback about the project is positive.


Author(s):  
Jop Vermeer ◽  
Leonardo Scandolo ◽  
Elmar Eisemann

Ambient occlusion (AO) is a popular rendering technique that enhances depth perception and realism by darkening locations that are less exposed to ambient light (e.g., corners and creases). In real-time applications, screen-space variants, relying on the depth buffer, are used due to their high performance and good visual quality. However, these only take visible surfaces into account, resulting in inconsistencies, especially during motion. Stochastic-Depth Ambient Occlusion is a novel AO algorithm that accounts for occluded geometry by relying on a stochastic depth map, capturing multiple scene layers per pixel at random. Hereby, we efficiently gather missing information in order to improve upon the accuracy and spatial stability of conventional screen-space approximations, while maintaining real-time performance. Our approach integrates well into existing rendering pipelines and improves the robustness of many different AO techniques, including multi-view solutions.


2021 ◽  
Vol 13 (3) ◽  
pp. 1458
Author(s):  
Daeryong Park ◽  
Huan-Jung Fan ◽  
Jun-Jie Zhu ◽  
Taesoon Kim ◽  
Myoung-Jin Um ◽  
...  

This study evaluated a fuzzy technique for order performance by similarity to ideal solution (TOPSIS) as a multicriteria decision making system that compensates for missing information with undefined weight factor criteria. The suggested Fuzzy TOPSIS was applied to ten potential dam sites in three river basins (the Han River, the Geum River, and the Nakdong River basins) in South Korea. To assess potential dam sites, the strategic environment assessment (SEA) monitored four categories: national preservation, endangered species, water quality, and toxic environment. To consider missing information, this study applied the Monte Carlo Simulation method with uniform and normal distributions. The results show that effects of missing information generation with one fuzzy set in GB1 site of the Geum River basin are not great in fuzzy positive-ideal solution (FPIS) and fuzzy negative-ideal solution (FNIS) estimations. However, the combination of two fuzzy sets considering missing information in Gohyun stream (NG) and Hoenggye stream (NH) sites of the Nakdong River basin has a great effect on estimating FPIS, FNIS, and priority ranking in Fuzzy TOPSIS applications. The sites with the highest priority ranking in the Han River, Geum River, and Nakdong River basins based on Fuzzy TOPSIS are the Dal stream 1 (HD1), Bocheong stream 2 (GB2) and NG sites. Among the sites in all river basins, the GB2 site had the highest priority ranking. Consequently, the results coincided with findings of previous studies based on multicriteria decision making with missing information and show the applicability of Fuzzy TOPSIS when evaluating priority rankings in cases with missing information.


2011 ◽  
Vol 17 (S2) ◽  
pp. 978-979
Author(s):  
G Liu ◽  
I Robertson

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.


1928 ◽  
Vol 1 (3) ◽  
pp. 485-497 ◽  
Author(s):  
C. R. Johnson

Abstract The rates of evolution of gas from carbon black with variation of time, temperature, and pressure have been determined. Complete analyses have been made of five types of carbon black, which involve an organic combustion of the original sample, an organic combustion of the sample after the gases have been removed, a determination of the loss in weight represented by the gases removed, analyses of the gases removed, and finally a complete accounting, or balance, of the carbon in the steps considered. In an attempt to supply some missing information not revealed by the foregoing, some special gas analyses under varying conditions were made. The relationship between the amount and composition of volatile matter evolved from carbon blacks and the properties imparted to vulcanized rubber when compounded with these blacks has been studied.


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