A first approximation for quantization of singular spaces

SummaryAim: While FDG full ring PET (FRPET) has been gradually accepted in oncology, the role of the cheaper gamma camera based alternatives (GCPET) is less clear. Since technology is evolving rapidly, “tracker trials” would be most helpful to provide a first approximation of the relative merits of these alternatives. As difference in scanner sensitivity is the key variable, head-to-head comparison with FRPET is an attractive study design. This systematic review summarises such studies. Methods: Nine studies were identified until July 1, 2000. Two observers assessed the methodological quality (Cochrane criteria), and extracted data. Results: The studies comprised a variety of tumours and indications. The reported GC- and FRPET agreement for detection of malignant lesions ranged from 55 to 100%, but with methodological limitations (blinding, standardisation, limited patient spectrum). Mean lesion diameter was 2.9 cm (SD 1.8), with only about 20% <1.5 cm. The 3 studies with the highest quality reported concordances of 74-79%, for the studied lesion spectrum. Contrast at GCPET was lower than that of FRPET, contrast and detection agreement were positively related. Logistic regression analysis suggested that pre-test indicators might be used to predict FRPET-GCPET concordance. Conclusion: In spite of methodological limitations, “first generation” GCPET devices detected sufficient FRPET positive lesions to allow prospective evaluation in clinical situations where the impact of FRPET is not confined to detection of small lesions (<1.5 cm). The efficiency of head-to-head comparative studies would benefit from application in a clinically relevant patient spectrum, with proper blinding and standardisation of acquisition procedures.

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Wildfire risk and hazard: procedures for the first approximation

10.2737/rmrs-gtr-235 ◽

2010 ◽

Cited By ~ 25

Author(s):

David E. Calkin ◽

Alan A. Ager ◽

Julie Gilbertson-Day

Keyword(s):

Wildfire Risk ◽

First Approximation

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First-approximation reduction of gravity data with the aid of a programmable pocket calculator

Open-File Report ◽

10.3133/ofr77600 ◽

1977 ◽

Author(s):

Wilfred P. Hasbrouck

Keyword(s):

Gravity Data ◽

Pocket Calculator ◽

First Approximation

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Napfmarathon versus Stadtmarathon: Eine Annäherung an das Konzept des Leistungskilometers

Swiss Sports & Exercise Medicine ◽

10.34045/ssem/2015/1 ◽

2015 ◽

Vol 63 (1) ◽

Keyword(s):

Accurate Estimation ◽

Horizontal Distance ◽

First Approximation ◽

The City

The aim of this study was to investigate differences in course times of a mountainmarathon (Napfmarathon) versus a city Marathon. Therefore all participants of Napfmarathon were screened concerning a double participation on a city marathon (Zürich, Winterthur, Lausanne, Luzern) and the course time were compared. Of key interest was the influence of ascents and descents which were quantified according to guidelines of Youth & Sport (Jugend + Sport / Jeunesse et Sport), whereby in first approximation 100 meter of ascent, 150 meter of descent (more than 20%) and 1 km of horizontal distance were taken as a simallar performance correlat. For the identified double starter different average times per km resulted. For the city marathon with an average time of 4 min 52 sec and for the Napfmarathon with 4 min 28 sec. If speed per km was calculated only with ascent and horizontal distances having performance relevance an average time of 4 min 56 sec per km was identified. This effect seems to be independet from distance absolved, resulting for Halbmarathon on an average time of distance of 4 min 13 sec, for Napfmarathon of 4 min 4 sec and for the performance concept only with ascent an average time per km of 4 min 16 sec. These analysis reveal, that if only ascent is taxed average course times differ less than 5 sec for both distances. For these particular reasons we recommend for running events to calculate only based on ascent and horizontal distances making necessary adjustments based on length of course, steepness of ascent and descent, character of terain (middle-country, pre-alps, alpes) for accurate estimation of course times.

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Metaontology

10.1093/oso/9780198791485.003.0006 ◽

2018 ◽

Author(s):

Uriah Kriegel

Keyword(s):

Second Order ◽

Order Property ◽

First Order ◽

First Approximation

Brentano’s theory of judgment serves as a springboard for his conception of reality, indeed for his ontology. It does so, indirectly, by inspiring a very specific metaontology. To a first approximation, ontology is concerned with what exists, metaontology with what it means to say that something exists. So understood, metaontology has been dominated by three views: (i) existence as a substantive first-order property that some things have and some do not, (ii) existence as a formal first-order property that everything has, and (iii) existence as a second-order property of existents’ distinctive properties. Brentano offers a fourth and completely different approach to existence talk, however, one which falls naturally out of his theory of judgment. The purpose of this chapter is to present and motivate Brentano’s approach.

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Galaxy Formation: Some Comparisons between Theory and Observation

Symposium - International Astronomical Union ◽

10.1017/s0074180900033350 ◽

1983 ◽

Vol 100 ◽

pp. 391-399 ◽

Cited By ~ 1

Author(s):

S. Michael Fall

Keyword(s):

Galaxy Formation ◽

Total Mass ◽

Virial Theorem ◽

Velocity Dispersion ◽

Rotation Velocity ◽

Morphological Type ◽

Fundamental Parameter ◽

Mass Ratio ◽

First Approximation ◽

Type Form

Before theoretical ideas in this subject can be compared with observational data, it is necessary to consider the properties of galaxies that are likely to be relics of their formation. Most astronomers would agree that the list of important parameters should be headed by the total mass M, energy E and angular momentum J. Next on the list should probably be the relative contributions to these quantities from the disc and bulge components of galaxies and denoted D/B for the mass ratio. They can be estimated from the median (i.e. half-mass) radius R, velocity dispersion σ and rotation velocity v of each component, either through the virial theorem or through the luminosity L and an assumed value of M/L. As a first approximation, it is reasonable to suppose that galaxies of a given disc-to-bulge ratio or morphological type form a sequence with mass as the fundamental parameter. The comparison of theory with data is further simplified by considering the extreme cases of ellipticals, with D/B << 1, and late-type spirals, with D/B >> 1. The approach outlined below is to explore the consequences of relaxing in succession the constraints that E, J and M be conserved during the collapse of proto-galaxies. In this article I concentrate on theories that are based on some form of hierarchical clustering because the pancake and related theories are not yet refined enough for a detailed confrontation with observations.

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The two-dimensional hydrodynamical theory of moving aerofoils. IV

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1947.0019 ◽

1947 ◽

Vol 188 (1015) ◽

pp. 439-463

Keyword(s):

Stability Problem ◽

Two Dimensional ◽

Centre Of Gravity ◽

First Approximation ◽

Von Karman ◽

Moving Cylinder ◽

Period Equation ◽

The Stability ◽

Von Kármán ◽

Hydrodynamical Theory

In the first part of this paper opportunity has been taken to make some adjustments in certain general formulae of previous papers, the necessity for which appeared in discussions with other workers on this subject. The general results thus amended are then applied to a general discussion of the stability problem including the effect of the trailing wake which was deliberately excluded in the previous paper. The general conclusion is that to a first approximation the wake, as usually assumed, has little or no effect on the reality of the roots of the period equation, but that it may introduce instability of the oscillations, if the centre of gravity of the element is not sufficiently far forward. During the discussion contact is made with certain partial results recently obtained by von Karman and Sears, which are shown to be particular cases of the general formulae. An Appendix is also added containing certain results on the motion of a vortex behind a moving cylinder, which were obtained to justify certain of the assumptions underlying the trail theory.

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Industry foresight with intelligent agents

Human Systems Management ◽

10.3233/hsm-2000-19304 ◽

2000 ◽

Vol 19 (3) ◽

pp. 169-180

Author(s):

Pirkko Walden ◽

Christer Carlsson ◽

Shuhua Liu

Keyword(s):

Support System ◽

Intelligent Agents ◽

Business Environment ◽

Data Sources ◽

Modern Time ◽

First Approximation ◽

Quality And Reliability ◽

Java Platform ◽

Active Scanning

Modern time managers have access to many more data sources than managers of earlier times, and better instruments and resources to deal with large amounts of data. In principle, this means that they have a better command of facts and should be able to work out better assessments of their business environment. In reality, however, information overflow and problems with the quality and reliability of information complicate the picture. We have a support system with intelligent agents to help managers conduct constantly active scanning and interpretation activities with hundreds of data sources. The system was built on a Java platform and has been enhanced and developed in several versions. The first implementation was at the Alko Group (the producers of the Finlandia vodka). The system is expected to provide mangers with a broad and comprehensive first approximation of environmental trends and events as needed, and will help them extract useful information from large volumes of data. (Originally presented at the ISDSS’99 Conference, Melbourne, July 19–22, 1999.)

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Standards-Based Quantification in DTSA-II—Part I

Microscopy Today ◽

10.1017/s155192951100085x ◽

2011 ◽

Vol 19 (5) ◽

pp. 30-36 ◽

Cited By ~ 14

Author(s):

Nicholas W.M. Ritchie

Keyword(s):

Measured Spectrum ◽

Complex Material ◽

X Ray ◽

Software Vendor ◽

First Approximation ◽

Constituent Elements

Quantifying an X-ray spectrum is the process of converting a measured spectrum into an estimate of the composition of the material from which the spectrum was collected. In a certain sense, interpreting X-ray spectra is very simple. A spectrum from even the most complex material can be thought of as a sum of spectra from the constituent elements (see Figure 1). To first approximation, if you know the spectrum for the constituent pure elements, you can estimate the spectrum for the complex material. Regardless of the software vendor or the name of the algorithm, this is the basis for quantification of all X-ray spectra.

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