Topographic Roughness as Interquartile Range of the Second Derivatives: Calculation and Mapping

Author(s):  
A. A. Kokhanov ◽  
I. P. Karachevtseva ◽  
Anastasia Zharkova
Author(s):  
A. A. Kokhanov ◽  
A.Y. Bystrov ◽  
M. A. Kreslavsky ◽  
E. V. Matveev ◽  
I. P. Karachevtseva

For automation of measurements of morphometric parameters of surface relief various tools were developed and integrated into GIS. We have created a tool, which calculates statistical characteristics of the surface: interquartile range of heights, and slopes, as well as second derivatives of height fields as measures of topographic roughness. Other tools were created for morphological studies of craters. One of them allows automatic placing of topographic profiles through the geometric center of a crater. Another tool was developed for calculation of small crater depths and shape estimation, using C++ programming language. Additionally, we have prepared tool for calculating volumes of relief features from DTM rasters. The created software modules and models will be available in a new developed web-GIS system, operating in distributed cloud environment.


Author(s):  
A. A. Kokhanov ◽  
A.Y. Bystrov ◽  
M. A. Kreslavsky ◽  
E. V. Matveev ◽  
I. P. Karachevtseva

For automation of measurements of morphometric parameters of surface relief various tools were developed and integrated into GIS. We have created a tool, which calculates statistical characteristics of the surface: interquartile range of heights, and slopes, as well as second derivatives of height fields as measures of topographic roughness. Other tools were created for morphological studies of craters. One of them allows automatic placing of topographic profiles through the geometric center of a crater. Another tool was developed for calculation of small crater depths and shape estimation, using C++ programming language. Additionally, we have prepared tool for calculating volumes of relief features from DTM rasters. The created software modules and models will be available in a new developed web-GIS system, operating in distributed cloud environment.


1968 ◽  
Vol 11 (1) ◽  
pp. 5-17 ◽  
Author(s):  
Martin A. Young ◽  
Tom D. Downs

Ratings by observers are often used in speech pathology to measure complex speech dimensions; this seems reasonable since a speech “disorder” represents the product of an observer’s evaluation and a speaker’s performance. An index of the validity of these evaluations may be estimated by the amount of agreement among the observers. In this paper, the semi-interquartile range and the intraclass correlation are discussed as possible indices of agreement, and another index is suggested, based on the range of observer ratings. Under the assumption that the distribution of ratings is uniform when ratings are randomly assigned, that is, the observers show no agreement, tables were constructed to indicate the probability of any range for selected numbers of observers and rating scale categories. Some applications for this index concern the training of observers, estimating the number of observers needed, and the construction of master scales.


1994 ◽  
Vol 72 (04) ◽  
pp. 511-518 ◽  
Author(s):  
Valentine C Menys ◽  
Philip R Belcher ◽  
Mark I M Noble ◽  
Rhys D Evans ◽  
George E Drossos ◽  
...  

SummaryWe determined changes in platelet aggregability following cardiopulmonary bypass, using optical aggregometry to assess macroaggregation in platelet-rich plasma (PRP), and platelet counting to assess microaggregation both in whole blood and PRP. Hirudin was used as the anticoagulant to maintain normocalcaemia.Microaggregation (%, median and interquartile range) in blood stirred with collagen (0.6 µg/ml) was only marginally impaired following bypass (91 [88, 93] at 10 min postbypass v 95 (92, 96] prebypass; n = 22), whereas macroaggregation (amplitude of response; cm) in PRP stirred with collagen (1.0µg/ml) was markedly impaired (9.5 [8.0, 10.8], n = 41 v 13.4 [12.7,14.3], n = 10; p <0.0001). However, in PRP, despite impairment of macroaggregation (9.1 [8.5, 10.1], n = 12), microaggregation was near-maximal (93 [91, 94]), as in whole blood stirred with collagen. In contrast, in aspirin-treated patients (n = 14), both collagen-induced microaggregation in whole blood (49 [47, 52]) and macroaggregation in PRP (5.1 [3.8, 6.6]) were more markedly impaired, compared with control (both p <0.001).Similarly, in PRP, macroaggregation with ristocetin (1.5 mg/ml) was also impaired following bypass (9.4 [7.2, 10.7], n = 38 v 12.4 [10.0, 13.4]; p <0.0002, n = 20), but as found with collagen, despite impairment of macroaggregation (7.2 [3.5,10.9], n = 12), microaggregation was again near-maximal (96 [93,97]). The response to ristocetin was more markedly impared after bypass in succinylated gelatin (Gelo-fusine) treated patients (5.6 [2.8, 8.6], n = 17; p <0.005 v control), whereas the response to collagen was little different (9.3 v 9.5). In contrast to findings with collagen in aspirin-treated patients, the response to ristocetin was little different to that in controls (8.0 v 8.3). Impairment of macroaggregation with collagen or ristocetin did not correlate with the duration of bypass or the platelet count, indicating that haemodilution is not a contributory factor.In conclusion: (1) Macroaggregation in PRP, as determined using optical aggregometry, is specifically impaired following bypass, and this probably reflects impairment of the build-up of small aggregates into larger aggregates. (2) Impairment of aggregate growth and consolidation could contribute to the haemostatic defect following cardiac surgery.


1996 ◽  
Vol 76 (03) ◽  
pp. 328-332 ◽  
Author(s):  
Bernd Jilma ◽  
Peter Fasching ◽  
Christine Ruthner ◽  
Anna Rumplmayr ◽  
Sabine Ruzicka ◽  
...  

SummaryBased on findings that showed increased P-selectin expression on platelets and on choroidal microvessels of patients with insulin dependent diabetes mellitus (IDDM), we hypothesized that also plasma concentrations of circulating (c)P-selectin would be increased in these patients.The aim of this study was to compare the plasma levels of cP-selec-tin between non-smoking patients with IDDM, treated with an intensified insulin therapy, and healthy controls. The study design was prospective, cross-sectional and analyst-blinded. Subjects were matched individually for sex, age and body mass index. Plasma levels of cP-selectin and of von Willebrand antigen (vWF-Ag) were determined by enzyme linked immunoassays.Forty-two pairs were available for intergroup comparison. Median plasma concentrations of cP-selectin in patients with IDDM (285 ng/ml; interquartile range: 233-372) were on average 21% higher than those of controls (236 ng/ml; interquartile range: 175-296; p = 0.004). Also, median plasma levels of vWF-Ag were 10% higher in patients (96 U/dl; interquartile range: 82-127) than controls (87 U/dl; interquartile range: 70-104; p = 0.025). There was no correlation between plasma concentrations of cP-selectin and vWF-Ag levels in either group (p ώ0.05).In conclusion, our results of increased cP-selectin levels are in line with increased P-selectin expression on platelets and on choroidal microvessels found in patients with IDDM. In view of the currently developed small molecule inhibitors of cell adhesion molecules, these independent observations together may provide a sound rationale to select P-selectin as a target for treating or preventing IDDM-associated micro- or macrovascular complications.


2017 ◽  
Vol 919 (1) ◽  
pp. 7-12
Author(s):  
N.A Sorokin

The method of the geopotential parameters determination with the use of the gradiometry data is considered. The second derivative of the gravitational potential in the correction equation on the rectangular coordinates x, y, z is used as a measured variable. For the calculated value of the measured quantity required for the formation of a free member of the correction equation, the the Cunningham polynomials were used. We give algorithms for computing the second derivatives of the Cunningham polynomials on rectangular coordinates x, y, z, which allow to calculate the second derivatives of the geopotential at the rectangular coordinates x, y, z.Then we convert derivatives obtained from the Cartesian coordinate system in the coordinate system of the gradiometer, which allow to calculate the free term of the correction equation. Afterwards the correction equation coefficients are calculated by differentiating the formula for calculating the second derivative of the gravitational potential on the rectangular coordinates x, y, z. The result is a coefficient matrix of the correction equations and corrections vector of the free members of equations for each component of the tensor of the geopotential. As the number of conditional equations is much more than the number of the specified parameters, we go to the drawing up of the system of normal equations, from which solutions we determine the required corrections to the harmonic coefficients.


Filomat ◽  
2017 ◽  
Vol 31 (4) ◽  
pp. 1009-1016 ◽  
Author(s):  
Ahmet Akdemir ◽  
Özdemir Emin ◽  
Ardıç Avcı ◽  
Abdullatif Yalçın

In this paper, firstly we prove an integral identity that one can derive several new equalities for special selections of n from this identity: Secondly, we established more general integral inequalities for functions whose second derivatives of absolute values are GA-convex functions based on this equality.


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