Megaliths and Mathematics

Antiquity ◽  
1966 ◽  
Vol 40 (158) ◽  
pp. 121-128 ◽  
Author(s):  
Alexander Thom

It is becoming apparent that megalithic man possessed and used a considerable knowledge of geometry. As more of his constructions are unravelled, we obtain an increasing appreciation of his attainments. Undoubtedly he also observed the heavenly bodies and used them to tell the time of day or night and to tell the day of the year. To take geometry first, let us look at the various shapes which, in his hands, a ring of stone could take. To understand these rings fully it is necessary to appreciate that he used extensively a very precise unit of length—the megalithic yard (MY). The exact length of this unit has become known to us by an examination of simple circles and flattened circles. When the author produced the first batch of circle diameters there was no universally accepted statistical analysis for the determination of the reliability of a quantum such as the suggested value for the megalithic yard. Then Broadbent produced two papers providing exactly the methods required to find, from a set of measurements, the most probable value of the quantum and the probability level at which it could be accepted [1,2]. This last is very important because Hammersley had shown that almost any random set of (say) diameters will yield an apparent unit of some sort.

2018 ◽  
Vol 3 (2) ◽  
pp. 52-61
Author(s):  
Dzikra Arwie ◽  
Islawati

Leukocytes or white blood cells have a characteristic characteristic of different cells. Determination of the impression of the number of leukocytes is determined in the number of cells in the field of view. While the number of viewable field cells expressed is still quite varied. The purpose of this study was to determine the number of leukocytes in the field of view and expressed the impression of a sufficient amount. This research was conducted at the Laboratory of Health Analyst Department Panrita Husada Bulukumba on 9 April 2017 to 14 July 2017. This type of research is a laboratory observation that aims to determine the criteria for assessing the impression of the number of leukocytes on a peripheral blood smear. Data analysis using statistical analysis is the average and standard deviations to determine the impression of the number of leukocytes and use 3 inspection zones. The results of this study obtained results in zone IV the number of leukocyte impressions said to be sufficient was 7-10, in zone V the number of leukocyte impressions said to be sufficient was 4-9, and in zone VI the number of leukocyte impressions said to be sufficient was 3-8.  


1977 ◽  
Vol 12 (1) ◽  
pp. 27-50 ◽  
Author(s):  
L.A. Behie ◽  
J.E. Zajic ◽  
D. Berk ◽  
R.J.P. Brouzes ◽  
V.A. Naish

Abstract Although Daphnia magna have been widely used in the determination of the toxicity of various substances, there are no reports in the literature that describe a rigorous bioassay method using this organism as a test species. The test described herein involves the standariza-tion of various important aspects of the method such as the age of the test organisms, and the dilution water used for the preparation of the various toxicant concentrations. Also described is a simple method for the statistical analysis of the results. The sensitivity of the proposed bioassay is demonstrated by determining the toxicity of various pulp and paper effluents. Finally, extensive bioassays were carried out simultaneously with rainbow trout and Daphnia magna indicating that Daphnia are as good a biological indicator of acute toxicity as fish.


1972 ◽  
Vol 48 ◽  
pp. 101-103
Author(s):  
R. J. Anderle

Locations of Doppler satellite observing stations have been revised to obtain a set which is more self-consistent and more consistent with the CIO pole. Residuals of satellite observations for 1970 have been analyzed using the new coordinates to determine mean and standard errors for five days of observations of latitude versus station, time of day, and elevation angle. The accuracy of the determination of latitude is about 4 meters at moderate and high elevation angles. But since more satellite passes occur at lower elevation angles, the accuracy of determination of a component of position based on five days of observation of one satellite is only about 2 meters.


1966 ◽  
Vol 49 (3) ◽  
pp. 511-515 ◽  
Author(s):  
R W Henningson

Abstract Bath level, sample temperature, rate of stirring, degree of supercooling, sample size, sample isolation, and refreezing of the sample were the variables in the thermistor cryoscopic method for the determination of the freezing point value of milk chosen for study. Freezing point values were determined for two samples of milk and two secondary salt standards utilizing eight combinations of the seven variables in two test patterns. The freezing point value of the salt standards ranged from –0.413 to –0.433°C and from –0.431 to –0.642°C. The freezing point values of the milk samples ranged from –0.502 to –0.544°C and from –0.518 to –0.550°C. Statistical analysis of the data showed that sample isolation was a poor procedure and that other variables produced changes in the freezing point value ranging from 0.001 to 0.011°C. It is recommended that specific directions be instituted for the thermistor cryoscopic method, 15.040–15.041, and that the method be subjected to a collaborative study.


Author(s):  
Lorenzo Ferrari ◽  
Guido Soldi ◽  
Alessandro Bianchini ◽  
Enzo Dalpane

A good prediction of the failure ratio of wind turbine (WT) components is pivotal to define a correct maintenance program and reduce the downtime periods. Even a small failure can lead to long downtime periods and high repairing costs. The installation sites, which generally have limited accessibility, and the necessity of special facilities to reach the components inside the nacelle, also play a key role in the correct management of WTs. In this study, a detailed survey on the failures occurred to the WTs managed by the Italian operator “e2i energie speciali” (more than 550 machines) over 16 years was performed and the results were analyzed in detail. Each failure was classified by considering the damaged component and the related downtime period. The analysis allowed the determination of several useful results such as the trend of failure occurrence with machine age and the identification of components and macrocomponents which are more critical in terms of both number of occurrences and downtime periods. The combination of component failure occurrences and related downtime periods was also computed to estimate which component is most critical for WT operation.


Evolution ◽  
1980 ◽  
Vol 34 (6) ◽  
pp. 1205-1211 ◽  
Author(s):  
M. R. Jeffords ◽  
G. P. Waldbauer ◽  
J. G. Sternburg
Keyword(s):  

2008 ◽  
Vol 40 (01) ◽  
pp. 31-48
Author(s):  
Markus Kiderlen

We discuss the determination of the mean normal measure of a stationary random set Z ⊂ ℝ d by taking measurements at the intersections of Z with k-dimensional planes. We show that mean normal measures of sections with vertical planes determine the mean normal measure of Z if k ≥ 3 or if k = 2 and an additional mild assumption holds. The mean normal measures of finitely many flat sections are not sufficient for this purpose. On the other hand, a discrete mean normal measure can be verified (i.e. an a priori guess can be confirmed or discarded) using mean normal measures of intersections with m suitably chosen planes when m ≥ ⌊d / k⌋ + 1. This even holds for almost all m-tuples of k-dimensional planes are viable for verification. A consistent estimator for the mean normal measure of Z, based on stereological measurements in vertical sections, is also presented.


Author(s):  
Alessana F. Schlichting ◽  
Edna M. Bonfim-Silva ◽  
Matheus de C. Silva ◽  
William Pietro-Souza ◽  
Tonny J. A. da Silva ◽  
...  

ABSTRACT The objective of this study was to verify the efficiency of two portable chlorophyll meters (Minolta SPAD® 502 and Falker ClorofiLOG® 1030) in assessing the nutritional status of wheat plants, correlating the indices from the devices and the direct determination of chlorophyll content with the concentration of nitrogen (N) in the plant. The experiment was conducted in a greenhouse, in pots with 5 dm3 of Oxisol, in a completely randomized design, with six N doses (0, 80, 160, 240, 320 and 400 mg dm-3) and five replicates. At 47 days after emergence, the readings of SPAD and Falker indices and the quantification of chlorophyll content and N concentration in wheat plants were performed, as well as analysis of variance and correlation test, both at 0.05 probability level. The chlorophyll meters Minolta SPAD® 502 and Falker ClorofiLOG® 1030 do not differ with respect to the indirect determination of chlorophyll in wheat plants. The Falker chlorophyll index was statistically equal to the chlorophyll content. Indirect chlorophyll indices and chlorophyll content showed a high correlation with the N concentration in the plant.


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