scholarly journals A System for In-Line 3D Inspection without Hidden Surfaces

Sensors ◽  
2018 ◽  
Vol 18 (9) ◽  
pp. 2993 ◽  
Author(s):  
Juan-Carlos Perez-Cortes ◽  
Alberto Perez ◽  
Sergio Saez-Barona ◽  
Jose-Luis Guardiola ◽  
Ismael Salvador
Keyword(s):  
Maximum Error ◽  
Blind Spot ◽  
Variable Number ◽  
Production Lines ◽  
Surface Appearance ◽  
Geometric Configurations ◽  
Mechanical Handling ◽  
Volumetric Representation ◽  
The Common ◽  
Visible Volume

This work presents a 3D scanner able to reconstruct a complete object without occlusions, including its surface appearance. The technique presents a number of differences in relation to current scanners: it does not require mechanical handling like robot arms or spinning plates, it is free of occlusions since the scanned part is not resting on any surface and, unlike stereo-based methods, the object does not need to have visual singularities on its surface. This system, among other applications, allows its integration in production lines that require the inspection of a large volume of parts or products, especially if there is an important variability of the objects to be inspected, since there is no mechanical manipulation. The scanner consists of a variable number of industrial quality cameras conveniently distributed so that they can capture all the surfaces of the object without any blind spot. The object is dropped through the common visual field of all the cameras, so no surface or tool occludes the views that are captured simultaneously when the part is in the center of the visible volume. A carving procedure that uses the silhouettes segmented from each image gives rise to a volumetric representation and, by means of isosurface generation techniques, to a 3D model. These techniques have certain limitations on the reconstruction of object regions with particular geometric configurations. Estimating the inherent maximum error in each area is important to bound the precision of the reconstruction. A number of experiments are presented reporting the differences between ideal and reconstructed objects in the system.

scholarly journals Heterozygosity and Chain Multivalents during Meiosis Illustrate Ongoing Evolution as a Result of Multiple Holokinetic Chromosome Fusions in the Genus Melinaea (Lepidoptera, Nymphalidae)

2017 ◽  
Vol 153 (4) ◽  
pp. 213-222 ◽  
Author(s):  
Melanie McClure ◽  
Bernard Dutrillaux ◽  
Anne-Marie Dutrillaux ◽  
Vladimir Lukhtanov ◽  
Marianne Elias
Keyword(s):  
Chromosome Evolution ◽  
Taxonomic Revision ◽  
Variable Number ◽  
Chromosome Fusion ◽  
Meiotic Chromosomes ◽  
In Captivity ◽  
Chromosome Fusions ◽  
The Common ◽  
Multiple Spindle ◽  
Complex Chromosome

Mitotic and meiotic chromosomes from 2 taxa of the genus Melinaea, M. satevis cydon and M. “satevis” tarapotensis (Lepidoptera: Nymphalidae), and from hybrids produced in captivity were obtained using an improved spreading technique and were subsequently analyzed. In one of the taxa, the presence of trivalents and tetravalents at diakinesis/metaphase I is indicative of heterozygosity for multiple chromosome fusions or fissions, which might explain the highly variable number of chromosomes previously reported in this genus. Two large and complex multivalents were observed in the meiotic cells of the hybrid males (32 chromosomes) obtained from a cross between M. “s.” tarapotensis (28 chromosomes) and M. s. cydon (40-43 chromosomes). The contribution of the 2 different haploid karyotypes to these complex figures during meiosis is discussed, and a taxonomic revision is proposed. We conclude that chromosome evolution is active and ongoing, that the karyotype of the common ancestor consisted of at least 48 chromosomes, and that evolution by chromosome fusion rather than fission is responsible for this pattern. Complex chromosome evolution in this genus may drive reproductive isolation and speciation, and highlights the difficulties inherent to the systematics of this group. We also show that Melinaea chromosomes, classically considered as holocentric, are attached to unique, rather than multiple, spindle fibers.

Larval morphology of Paroster Sharp, 1882 (Coleoptera: Dytiscidae: Hydroporinae): reinforcement of the hypothesis of monophyletic origin and discussion of phenotypic accommodation to a hypogaeic environment

Zootaxa ◽  
2009 ◽  
Vol 2274 (1) ◽  
pp. 1-44 ◽  
Author(s):  
YVES ALARIE ◽  
MARIANO C. MICHAT ◽  
CHRIS H. S. WATTS
Keyword(s):  
Abdominal Segment ◽  
Relative Elongation ◽  
Cladistic Analysis ◽  
Head Capsule ◽  
Variable Number ◽  
The Other ◽  
Labial Palpus ◽  
Monophyletic Origin ◽  
Large Head ◽  
The Common

The larvae of 13 species (six epigaeic and seven hypogaeic) of the Australian endemic genus Paroster Sharp, 1882 are described with an emphasis on chaetotaxy of the head capsule, head appendages, legs, last abdominal segment and urogomphi. A cladistic analysis of 41 Hydroporinae species and 63 informative characters supports a monophyletic origin of members of Paroster, which share a labial palpus comprised of three palpomeres and the absence of the primary seta FE7. Contrary to their epigaeic counterparts, larvae of hypogaeic Paroster species have turned out to be very divergent morphologically. In addition to the common characteristics associated with hypogaeic living (i.e., absence of eye, reduced pigmentation, and thin or soft exoskeleton), larvae of these species have undergone a relative elongation/ enlargement of the head capsule and a more elongate and narrower mandible and have developed a variable number of secondary temporal spines. Compared to the other stygobitic species studied, larvae of Paroster hinzeae (Watts & Humphreys, 2001), P. macrosturtensis (Watts & Humphreys, 2006), P. stegastos (Watts & Humphreys, 2003) and P. darlotensis (Watts & Humphreys, 2003) evolved a disproportionately large head capsule relative to body size. Larvae of P. wedgeensis (Watts & Humphreys, 2003) and P. mesosturtensis (Watts & Humphreys, 2006) are deemed to have deviated the least from the hypothetical epigaeic Paroster groundplan.

Brucella ceti from two striped dolphins stranded on the Apulia coastline, Italy

2014 ◽  
Vol 63 (2) ◽  
pp. 325-329 ◽  
Author(s):  
Giuliano Garofolo ◽  
Katiuscia Zilli ◽  
Pasquale Troiano ◽  
Antonio Petrella ◽  
Francesca Marotta ◽  
...  
Keyword(s):  
Marine Mammals ◽  
Tandem Repeats ◽  
Variable Number ◽  
Sequence Type ◽  
Epidemiological Investigation ◽  
Stenella Coeruleoalba ◽  
First Case ◽  
Microbiological Methods ◽  
The Common ◽  
Common Sequence

Since 1994, when Brucella ceti was first isolated from an aborted dolphin fetus, several cases have been reported worldwide. The first case of B. ceti in the Mediterranean (and in Italy), however, was recorded only in 2012, off the coast of Tuscany. Extensive studies, using serological and microbiological methods, have documented this bacterium in dolphins and demonstrated its zoonotic potential. We describe the typing of two B. ceti strains isolated from striped dolphins (Stenella coeruleoalba) stranded on the southern Apulia coastline. B. ceti isolates were conventionally typed, and then genotyped by both the multilocus sequence typing (MLST) and the multilocus variable number of tandem repeats typing (MLVA) methodologies to infer phylogeny and potential epidemiological links between the two cases. The two isolates were identified through MLST analysis as belonging to the common sequence type 26 (ST26), while MLVA analysis, having established that the two isolates have identical profiles, assigned them to a novel genotype within cluster A – a unique representative of a new Mediterranean subcluster. The results thus revealed a link between the two cases studied, demonstrating the usefulness of MLST and MLVA for the epidemiological investigation of brucellae among marine mammals.

scholarly journals Surveillance of Circulating Bordetella pertussis Strains in Europe during 1998 to 2015

2018 ◽  
Vol 56 (5) ◽  
Author(s):  
Alex-Mikael Barkoff ◽  
Jussi Mertsola ◽  
Denis Pierard ◽  
Tine Dalby ◽  
Silje Vermedal Hoegh ◽  
...  
Keyword(s):  
Bordetella Pertussis ◽  
Virulence Genes ◽  
Genomic Structure ◽  
Variable Number Tandem Repeat ◽  
Variable Number ◽  
Content Type ◽  
Present Collection ◽  
Genomic Analyses ◽  
The Common ◽  
Induced Immunity

ABSTRACT One reason for increased pertussis incidence is the adaptation of Bordetella pertussis to vaccine-induced immunity by modulating its genomic structure. This study, EUpert IV, includes 265 isolates collected from nine European countries during 2012 to 2015 ( n = 265) and compares the results to previous EUpert I to III studies (1998 to 2009). The analyses included genotyping, serotyping, pulsed-field gel electrophoresis (PFGE), and multilocus variable-number tandem-repeat analysis (MLVA). Genotyping results showed only small variations among the common virulence genes of B. pertussis . The frequencies of serotypes Fim2 and Fim3 varied among the four collections. Genomic analyses showed that MLVA type 27 increased to 80% between the periods of 1998 to 2001 and 2012 to 2015. Two PFGE profiles, BpSR3 (29.4%) and BpSR10 (27.2%), constituted more than 50% of the circulating isolates in the present collection. Our study indicates that the European B. pertussis population is changing and became more homogenous after the introduction of acellular pertussis vaccines.

Systematic Hysteresis Analysis for Dynamic Comparators

2019 ◽  
Vol 28 (06) ◽  
pp. 1950100 ◽  
Author(s):  
Leïla Khanfir ◽  
Jaouhar Mouïne
Keyword(s):  
Maximum Error ◽  
Input Voltage ◽  
Cmos Technology ◽  
Design Parameters ◽  
Mathematical Approach ◽  
Clock Frequency ◽  
Stable States ◽  
The Common ◽  
Dynamic Comparators ◽  
Hysteresis Control

Comparator hysteresis is a memory phenomenon allowing outputs maintaining their past stable states until the input difference overcomes a given threshold voltage. In some applications, such as ADCs and memories, hysteresis is a deterministic error that should be minimized. In others, it can be considered as one of the design parameters, such as in implementing hysteresis control-based systems such as peak detectors and spectrum analyzers. In any case, the designer should be aware of how to estimate hysteresis to achieve the desired performances. This paper presents a mathematical approach to estimate hysteresis in clocked latch comparators. It has been demonstrated that hysteresis is not only sensitive to the clock frequency, but also to several design parameters including the transistors sizes, the common mode input voltage and the tracked input frequencies. The analysis results are validated through electrical simulations using a commercially available 0.18[Formula: see text][Formula: see text]m CMOS technology showing a maximum error of 8.6%.

Structure of High Tc Oxide Superconductors

MRS Bulletin ◽  
1989 ◽  
Vol 14 (1) ◽  
pp. 27-30 ◽  
Author(s):  
Ivan K. Schuller ◽  
J.D. Jorgensen
Keyword(s):  
Variable Number ◽  
Oxide Superconductors ◽  
Detailed Knowledge ◽  
Coupling Mechanism ◽  
High Tc ◽  
Square Planar ◽  
Structural Principles ◽  
The Common ◽  
The Individual ◽  
New Compounds

Our understanding of the superconducting mechanism in the newly discovered oxide superconductors is closely connected with a detailed knowledge of the structural properties displayed by these materials. Moreover, it is important to explore possible connections between structural and superconducting properties and to establish general structural principles which can guide our search for new compounds.We present here a survey of the structures of the recently discovered oxide superconductors. The common feature of these structures (with the exception of cubic Ba1-x Kx BiO3-y) is the presence of one or more planes of copper atoms with four strongly bonded oxygen atom neighbors in a square planar arrangement at a distance of approximately 1.90 Å (“CuO2 planes”). In some structures these planes occur in groups, with the individual planes inside a group being separated by one Y or Ca layer and the groups being intercalated by a variable number of LaO, BaO, CuO, TIO and/or BiO layers. (The intercalated CuO layer is crystallographically distinct from the “CuO2 plane”). A natural model for superconductivity which arises from these structures is that the conductivity occurs predominantly in the Cu02 planes, while the other (intercalated) layers provide in some fashion carriers and/or the coupling mechanism necessary for the superconductivity.

Variable Number of Multi-Sensor Fusion for Indoor RFID Tracking System

2013 ◽  
Vol 385-386 ◽  
pp. 654-657
Author(s):  
Xue Bo Jin ◽  
Jiang Feng Wang ◽  
Hui Yan Zhang ◽  
Li Hong Cao
Keyword(s):  
Tracking System ◽  
Estimation Algorithm ◽  
Measurement Model ◽  
Variable Number ◽  
Tracking Problem ◽  
Rfid Technology ◽  
Active Rfid ◽  
Target Trajectory ◽  
The Common ◽  
Indoor Tracking

We present a new method to accurately tracking persons indoors by active RFID technology. To deal with nonlinear measurement model, the EKF(extended Kalman filter) is used to estimate the target trajectory. This paper developed the fusion estimation algorithm for the common indoor tracking problem with the reader at any location and fusion estimation with variable number of multi-sensor system. Simulations show the algorithm developed here can adaptively adjust the model parameter while tracking and obtain good estimation performance for indoor RFID tracking.

Immigration and Production Line Margins in the 1950s Vehicle Building Industry

1994 ◽  
Vol 36 (1) ◽  
pp. 18-36
Author(s):  
Robert Tierney
Keyword(s):  
Automotive Industry ◽  
Production Line ◽  
Mass Scale ◽  
Building Industry ◽  
Production Lines ◽  
Mass Recruitment ◽  
The Common ◽  
The 1950S ◽  
Exerted Pressure

In the 1950s, the Australian automotive industry exerted pressure on the Common wealth government to import southern European labour on a mass scale. The employers' aim was to overcome severe labour shortages on the production lines, particularly in the areas where Australian-born and non-Mediterranean immi grant men were generally reluctant to work. Prior to and during the early part of this decade, the Vehicle Builders Employees Federation (since January 1993 the Automotive section of the Automotive, Metal and Engineering Union) were exploit ing the labour shortages in the industry to strengthen their claim for the introduc tion of a uniform, semi-skilled, second-class tradesmen's margin for production line workers. Two major car makers were already paying this semi-skilled wage to line workers. The mass recruitment of southern European labour by the vehicle building industry was one of the factors undermining the production line workers' claim for this semi-skilled margin. The other important factors were Commissioner Galvin's rigid views about the marginal rates and comparative wage justice and the Vehicle Builders Employees Federation's organizational weakness and remote ness from its members.

scholarly journals Bacillus anthracis Phylogeography: New Clues From Kazakhstan, Central Asia

2021 ◽  
Vol 12 ◽  
Author(s):  
Alexandr Shevtsov ◽  
Larissa Lukhnova ◽  
Uinkul Izbanova ◽  
Jean-Philippe Vernadet ◽  
Marat Kuibagarov ◽  
...  
Keyword(s):  
Bacillus Anthracis ◽  
Central Asia ◽  
Tandem Repeats ◽  
Epidemiological Data ◽  
Variable Number ◽  
Technical Institute ◽  
The Past ◽  
Independent Events ◽  
The Common ◽  
Common Era

This article describes Bacillus anthracis strains isolated in Kazakhstan since the 1950s until year 2016 from sixty-one independent events associated with anthrax in humans and animals. One hundred and fifty-four strains were first genotyped by Multiple Locus VNTR (variable number of tandem repeats) Analysis (MLVA) using 31 VNTR loci. Thirty-five MLVA31 genotypes were resolved, 28 belong to the A1/TEA group, five to A3/Sterne-Ames group, one to A4/Vollum and one to the B clade. This is the first report of the presence of the B-clade in Kazakhstan. The MLVA31 results and epidemiological data were combined to select a subset of seventy-nine representative strains for draft whole genome sequencing (WGS). Strains from Kazakhstan significantly enrich the known phylogeny of the Ames group polytomy, including the description of a new branch closest to the Texas, United States A.Br.Ames sublineage stricto sensu. Three among the seven currently defined branches in the TEA polytomy are present in Kazakhstan, “Tsiankovskii”, “Heroin”, and “Sanitary Technical Institute (STI)”. In particular, strains from the STI lineage are largely predominant in Kazakhstan and introduce numerous deep branching STI sublineages, demonstrating a high geographic correspondence between “STI” and Kazakhstan, Central Asia. This observation is a strong indication that the TEA polytomy emerged after the last political unification of Asian steppes in the fourteenth century of the Common Era. The phylogenetic analysis of the Kazakhstan data and of currently available WGS data of worldwide origin strengthens our understanding of B. anthracis geographic expansions in the past seven centuries.

Catalogue reduction techniques

1978 ◽  
Vol 48 ◽  
pp. 389-390 ◽  
Author(s):  
Chr. de Vegt
Keyword(s):  
Adjustment Process ◽  
Proper Motions ◽  
Measuring Process ◽  
Aerial Photogrammetry ◽  
Reduction Techniques ◽  
Observational Technique ◽  
The Common ◽  
Astrometric Data

AbstractReduction techniques as applied to astrometric data material tend to split up traditionally into at least two different classes according to the observational technique used, namely transit circle observations and photographic observations. Although it is not realized fully in practice at present, the application of a blockadjustment technique for all kind of catalogue reductions is suggested. The term blockadjustment shall denote in this context the common adjustment of the principal unknowns which are the positions, proper motions and certain reduction parameters modelling the systematic properties of the observational process. Especially for old epoch catalogue data we frequently meet the situation that no independent detailed information on the telescope properties and other instrumental parameters, describing for example the measuring process, is available from special calibration observations or measurements; therefore the adjustment process should be highly self-calibrating, that means: all necessary information has to be extracted from the catalogue data themselves. Successful applications of this concept have been made already in the field of aerial photogrammetry.

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