Mining Top-k Frequent/Regular Patterns Based on User-Given Trade-Off between Frequency and Regularity

Each molecule of ferritin (d = 130Å) contains a core of iron surrounded by a 24-subunit protein shell. The amount of iron stored is variable and is present within the central cavity (d = 80Å) as a hydrated ferric oxide equivalent to the mineral, ferrihydrite. Many early ultrastructural studies of ferritin detected regular patterns of a multiparticulate substructure in the iron-rich core [e.g., 3,4], Each small particle was termed a “micelle“; a theory became widely accepted that a core consisted of up to six micelles positioned at the vertices of an octahedron. Other workers recognized that the apparent micelles were smaller or even disappeared if images were recorded closer to exact focus [e.g., 5]. In 1969, Haydon clearly established that the observed substructure was really an imaging artifact; each apparent micelle was only a dot in the underfocused phase contrast image of the supporting film superimposed on the amplitude image of the strongly scattering metal.

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The buckling of thin EM specimens

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100177386 ◽

1990 ◽

Vol 48 (4) ◽

pp. 850-851

Author(s):

A.R. Thölén

Keyword(s):

Electron Microscope ◽

Elastic Properties ◽

Crystal Surface ◽

Specimen Surface ◽

Radius Of Curvature ◽

Thin Foils ◽

Thin Electron ◽

Regular Patterns

Thin electron microscope specimens often contain irregular bend contours (Figs. 1-3). Very regular bend patterns have, however, been observed around holes in some ion-milled specimens. The purpose of this investigation is twofold. Firstly, to find the geometry of bent specimens and the elastic properties of extremely thin foils and secondly, to obtain more information about the background to the observed regular patterns.The specimen surface is described by z = f(x,y,p), where p is a parameter, eg. the radius of curvature of a sphere. The beam is entering along the z—direction, which coincides with the foil normal, FN, of the undisturbed crystal surface (z = 0). We have here used FN = [001]. Furthermore some low indexed reflections are chosen around the pole FN and in our fcc crystal the following g-vectors are selected:

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A Flow-Preserving Algorithm for the Time-Cost Trade-Off Problem

IIE Transactions ◽

10.1080/05695558208974589 ◽

1982 ◽

Vol 14 (2) ◽

pp. 109-113 ◽

Cited By ~ 4

Author(s):

Suleyman Tufekci

Keyword(s):

Time Cost ◽

Trade Off

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Dual Goals for Speed and Accuracy on the Same Performance Task

Journal of Personnel Psychology ◽

10.1027/1866-5888/a000063 ◽

2012 ◽

Vol 11 (3) ◽

pp. 118-126 ◽

Cited By ~ 3

Author(s):

Olive Emil Wetter ◽

Jürgen Wegge ◽

Klaus Jonas ◽

Klaus-Helmut Schmidt

Keyword(s):

Memory Scanning ◽

Performance Task ◽

Performance Tasks ◽

Trade Off ◽

Test Experiment ◽

Trade Offs ◽

New Finding ◽

Sternberg Paradigm ◽

Speed Accuracy ◽

Speed And Accuracy

In most work contexts, several performance goals coexist, and conflicts between them and trade-offs can occur. Our paper is the first to contrast a dual goal for speed and accuracy with a single goal for speed on the same task. The Sternberg paradigm (Experiment 1, n = 57) and the d2 test (Experiment 2, n = 19) were used as performance tasks. Speed measures and errors revealed in both experiments that dual as well as single goals increase performance by enhancing memory scanning. However, the single speed goal triggered a speed-accuracy trade-off, favoring speed over accuracy, whereas this was not the case with the dual goal. In difficult trials, dual goals slowed down scanning processes again so that errors could be prevented. This new finding is particularly relevant for security domains, where both aspects have to be managed simultaneously.

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