Theoretical Lidar Point Density for Topographic Mapping in the Largest Scales

When ordering LiDAR data, LiDAR point density per surface unit is important information with decisive influence on the price of the LiDAR survey. The paper first deals with the theoretical calculation of the minimum LiDAR point density, necessary for the acquisition of topographic data of the largest scales. For this purpose the sampling theorem is used. However, since topographic objects (roads, water bodies, etc.) and phenomena represented on topographic maps and in topographic bases are in many cases located under vegetation, also the rate of laser beam penetration through vegetation for the area where the topographic data are to be gathered has to be known. In a research on a test case conducted in the area of the town Nova Gorica we calculated the rate of laser beam penetration for four different vegetation types: scarce Mediterranean vegetation, thick thermophilic deciduous forest, mixed vegetation (meadows, orchards and forest) and built-up area. By connecting the theoretic minimum LiDAR point density with the rate of penetration, we defined the minimum LiDAR point density for the needs of data acquisition on topographic maps of the largest scales or in topographic bases of comparable detail (from 1 : 1000 to 1 : 10,000)

Federico Bencovich: la fortuna critica, un itinerario

This paper aims to provide a summary of the fortuna critica of the Dalmatian painter Federico Bencovich (1677-1753), beginning with some biographical notes published in the 18th century finishing with some 21st century studies. The author wants to demonstrate how the successful cliché which consists in the common opinion that Bencovich is responsible for Tiepolo’s art’s formation, was largely created by Moschini’s opinion on Bencovich. Consequently, in the 20th century a lot of paintings, characterized by a genius and a sprightliness rococo’, were ascribed to the Dalmatian painter; but recently most of them have been assigned to other painters (young Tiepolo, Crosato, Mildorfer). The catalogue of Bencovich is becoming increasingly poorer than it already was, and maybe we should correct his role in the venetian survey of the 18th century

FAST AND RESISTANT PROCRUSTEAN BUNDLE ADJUSTMENT

In a recent paper (Fusiello and Crosilla, 2015) a Procrustean formulation of the bundle block adjustment has been presented, with a solution based on alternating least squares. This paper improves on it in two respects: it introduces a faster iterative scheme that minimizes the same cost function, thereby achieving the same accuracy, and makes the method resistant to rogue measures through iteratively reweighted least-squares. Empirical results confirm the effectiveness of these enhancements

Solving bundle block adjustment by generalized anisotropic Procrustes analysis

The paper presents a new analytical tool to solve the classical photogrammetric bundle block adjustment. The analytical model is based on the generalized extension of the anisotropic row-scaling Procrustes analysis, that has been recently proposed by the same authors to solve the image exterior orientation problem. The main advantage of the method is given by the fact that the problem solution does not require any approximate value of the unknown parameters, nor any linearization procedure. Moreover, the algorithm is exceedingly simple to describe and easy to implement. Empirical results indicate that a zero-information initialization of the iterative relaxation procedure leads almost always to the correct final least squares solution. Experiments confirm the accuracy of the proposed method, when compared to the results obtained by applying a classical photogrammetric bundle block adjustment

Errors-in-Variables Anisotropic Extended Orthogonal Procrustes Analysis

This letter presents a novel total least squares (TLS) solution of the anisotropic row-scaling Procrustes problem. The ordinary LS Procrustes approach finds the transformation parameters between origin and destination sets of observations minimizing errors affecting only the destination one. In this letter, we introduce the errors-in-variables model in the anisotropic Procrustes analysis problem and present a solution that can deal with the uncertainty affecting both sets of observations. The algorithm is applied to solve the image exterior orientation problem. Experiments show that the proposed TLS method leads to an accuracy in the parameters estimation that is higher than the one reached with the ordinary LS anisotropic Procrustes solution when the number of points, whose coordinates are known in both the image and the external systems, is small

Mechanical ond opto-chemical dating of the Turin Shroud

Abstract. The TS (Turin Shroud) is a linen cloth which enveloped the dead body of a tortured and crucified man that is believed by many to be the burial cloth of Jesus Christ. The linen fabric has been radiocarbon dated in 1988 to the Middle Age but a recent robust statistical analysis shows that the resulting age appears flawed by a systematic effect. The present paper discusses the results obtained using innovative dating methods based on the analysis of mechanical parameters (breaking strength, Young modulus and loss factor) and of opto- chemical ones (FT-IR and Raman). To obtain mechanical results it was necessary to build a particular cycling-loads machine able to measure the mechanical parameters of single flax fibers 1-3 mm long. A least squares multi linear regression (MLR) has been applied to the measured mechanical data estimating a TS age equal to 260 AD. Furthermore, two opto- chemical methods have been applied to test the linen fabric, obtaining a date of 250 BC by a FT-IR ATR analysis and a date of 30 AD by a Raman analysis. These two dates combined with the mechanical result, weighted through their estimated square uncertainty inverses, give a final date of the Turin Shroud of 90 AD \ub1200 years at 95% confidence level. While this date is both compatible with the time in which Jesus Christ lived in Palestine and with very recent results based on numismatic dating, it is not compatible with the 1988 radiocarbon measurements that should be repeated after the necessary clarifications relative to the possible environmental factors that could have biased the results

An automatic classification and robust segmentation procedure of spatial objects

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La linea sacra di S. Michele e la sfericità terrestre

Secondo diverse fonti, non del settore cartografico, la Linea Sacra di San Michele unisce sette santuari dedicati all’Arcangelo, dall’Irlanda a Israele, con una misteriosa e suggestiva linea retta. L’articolo, dopo aver ricordato la generale arbitrarieta? di tale affermazione in un contesto cartografico, dimostra in maniera statisticamente rigorosa che la Linea Sacra di S. Michele segue effettivamente una linea retta sulla rappresentazione di Mercatore, dimostrando cosi? l’appartenenza dei sette santuari ad una curva lossodromica sulla superficie terrestre. Si riportano infine i risultati dello studio di allineamento della Linea Sacra con il tramonto del sole nel giorno del solstizio d’estate. ABSTRACT According to several sources, not from the cartographic world, the Sacred Line of San Michele unites seven dedicated shrines to the Archangel, from Ireland to Israel, with a mysterious and suggestive straight line. The article, after recalling the general arbitrariness of this statement in a cartographic context, demonstrates in a manner statistically strict that the Line Sacra di S. Michele actually follows a straight line on the representation of Mercator, thus proving the membership of the seven sanctuaries at a rhumb line on the earth surface

La linea sacra di S. Michele e la sfericità terrestre

Secondo diverse fonti, non del settore cartografico, la Linea Sacra di San Michele unisce sette santuari dedicati all’Arcangelo, dall’Irlanda a Israele, con una misteriosa e suggestiva linea retta. L’articolo, dopo aver ricordato la generale arbitrarieta? di tale affermazione in un contesto cartografico, dimostra in maniera statisticamente rigorosa che la Linea Sacra di S. Michele segue effettivamente una linea retta sulla rappresentazione di Mercatore, dimostrando cosi? l’appartenenza dei sette santuari ad una curva lossodromica sulla superficie terrestre. Si riportano infine i risultati dello studio di allineamento della Linea Sacra con il tramonto del sole nel giorno del solstizio d’estate. ABSTRACT According to several sources, not from the cartographic world, the Sacred Line of San Michele unites seven dedicated shrines to the Archangel, from Ireland to Israel, with a mysterious and suggestive straight line. The article, after recalling the general arbitrariness of this statement in a cartographic context, demonstrates in a manner statistically strict that the Line Sacra di S. Michele actually follows a straight line on the representation of Mercator, thus proving the membership of the seven sanctuaries at a rhumb line on the earth surface

Error and Predicativity

The article surveys ideas emerging within the predicative tradition in the foundations of mathematics, and attempts a reading of predicativity constraints as highlighting different levels of understanding in mathematics. A connection is made with two kinds of error which appear in mathematics: local and foundational errors. The suggestion is that ideas originating in the predicativity debate as a reply to foundational errors are now having profound influence to the way we try to address the issue of local errors. Here fundamental new interactions between computer science and mathematics emerge