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SleevecoreWara, William January 2020 (has links)
The motivation for this work has been to develop a web platform for a game concept where the underlying code acts to enable users to customize their game markers and place orders for them. This report deals with the creation of this website that in itself is not a webstore in classical terms but rather offers a process of it’s own for users to pick the looks of a product, place it in a cart and pay for it. The website communicates with an external payment processor that has been implemented. The process also includes prepatory work and the handeling of graphics and both client and server-side coding. The report covers the programming of the website and speculates in its application of usability standards from evaluating of user tests. / Motivationen för detta arbete har varit att ta fram en webbplattform för ett spelkoncept där kodningen ligger till grund för användare att personanpassa sina spelmarkörer och beställa dem. Denna rapport avhandlar skapandet av denna webbsida som i sig skiljer sig från en webbutik i klassisk bemärkelse och istället erbjuder en egen process för att välja utseende på varor, placera dem i en kundkorg och betala för dem. Webbsidan kommunicerar med en extern betalningslösning som är implementerad på sidan. I arbetet ingår förutom förarbete även hanterandet av bildmaterial och både klient- och serverbaserad kodning. Rapporten täcker framtagandet av tekniken för webbsidan och spekulerar i dess anpassning till användarriktlinjer och olika användartyper efter utvärderingar baserade på genomförda tester.
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An exploratory investigation into the feasibility of turning the student identification card into a debit card: The case for the University of the Western CapeOsambo, Okoko January 2003 (has links)
Magister Commercii - MCom / This study investigates the financial, marketing as well as technological feasibility
of turning the current University of Western Cape (UWC) Student ID Card into a
more featured debit card called the "Hoop Kaarf'. This debit card will offer the
functionality of access to secure UWC areas, the purchase and use of
photocopying credits, the purchase of printing credits, taking out library books;
and identification, as the old student card does. It will also have the added
functionality of replacing cash when paying for vending machines, cafés, takeaways,
shops, supermarkets and withdrawing money from ATMs, at UWC, within
South Africa and outside the country.
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Structured Light Vision Systems Using a Robust Laser Stripe Segmentation MethodZhankun Luo (10745715) 05 May 2021 (has links)
In thesis, we propose a structured light vision system equipped with multi-cameras and multi-laser emitters for object height measurement or 3D reconstruction. The proposed method offers a better accuracy performance over a single camera system. The structured light method may fail the interference of reflection and scattering of light. We use U-Net to extract the laser region, obtain the laser stripe center after erosion and dilation, and finally reconstruct the point cloud corresponding to the laser stripe. Our experiments demonstrate that our structured light system with the U-Net can perform effectively and robustly in a complex environment.
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Genetic mapping of adult plant stripe rust resistance in the wheat cultivar KariegaRamburan, Viresh Premraj 04 1900 (has links)
Thesis (PhD (Agric)) -- Stellenbosch University, 2003. / ENGLISH ABSTRACT: Stripe (yellow) rust of wheat, caused by Puccinia striiformis f.sp. tritici, was first detected as a
single introduction into South Africa in 1996. Two additional pathotypes have since been
identified. Control of the disease may be achieved by use of genetic adult plant resistance
(APR) as is present in the local cultivar 'Kariega'. The aim of this project was to understand the
genetic basis of the APR in 'Kariega' to facilitate breeding of new varieties with genetic
resistance to stripe rust.
A partial linkage map of a 'Kariega X Avocet S' doubled haploid population covering all 21
wheat chromosomes was generated using 208 DNA markers, viz, 62 SSR, 133 AFLP, 3 RGA
and 10 SRAP markers, and 4 alternative loci. The different marker techniques detected varying
polymorphism, viz, overall SSR: 46%, AFLP: 7%, SRAP: 6% and RGA: 9%, and the markers
produced low levels of missing data (4%) and segregation distortion (5%). A significant feature
of the linkage map was the low polymorphism found in the D genome, viz, 19% of all mapped
DNA markers, 11% of all AFLP markers and 30% of the total genome map distance. A region
exhibiting significant segregation distortion was mapped to chromosome 4A and a seedling
resistance gene for stem rust (Puccinia graminis f.sp . tritici), Sr26, mapped to chromosome 6A
close to three SSR markers. The leaf tip necrosis gene, Ltn, which was also segregating in the
population, mapped to chromosome 7D. Protocols for SRAP and RGA were optimised, and
SRAP marker use in wheat genetic linkage studies is reported for the first time.
The linkage map was used together with growth chamber and replicated field disease scores for
QTL mapping. Chromosomes showing statistically significant QTL effects were then targeted
with supplementary SSR markers for higher resolution mapping. The quality of disease
resistance phenotypic data was confirmed by correlation analysis between the different scorers
for reaction type (0.799±0.023) and for transformed percentage leaf area infected
(0.942±0.007).
Major QTL were consistently identified on chromosome 7D (explaining some 25-48% of the
variation) and on chromosome 2B (21-46%) using transformed percentage leaf area infected and transformed reaction type scores (early and final) with interval mapping and modified
interval mapping techniques. Both chromosomal regions have previously been identified in
other studies and the 7D QTL is thought likely to be the previously mapped APR gene Yr 18.
Minor QTL were identified on chromosomes lA and 4A with the QTL on 4A being more
prominent at the early field scoring for both score types. A QTL evidently originating from
'Avocet S' was detected under growth chamber conditions but was not detected in the field,
suggesting genotype-environment interaction and highlighting the need for modifications of
growth chamber conditions to better simulate conditions in the field.
The genetic basis of the APR to stripe rust exhibited by 'Kariega' was established by mapping
of QTL controlling this trait. The linkage map constructed will be a valuable resource for
future genetic studies and provides a facility for mapping other polymorphic traits in the
parents of this population with a considerable saving in costs. / AFRIKAANSE OPSOMMING: Streep of geelroes van koring word veroorsaak deur Puccinia striiformis f. sp tritici, en is die
eerste keer in 1996 in Suid-Afrika na introduksie van 'n enkele patotipe waargeneem. Twee
verdere patotipes is sedertdien in Suid-Afrika gei"dentifiseer. Beheer van die siekte word veral
moontlik gemaak deur die gebruik van genetiese volwasseplantweerstand soos gei"dentifiseer in
die plaaslike kultivar 'Kariega'. Die doel van hierdie studie was om die genetiese grondslag van
die streeproesweerstand te ontrafel ten einde die teling van nuwe bestande kultivars moontlik te
maak.
'n Verdubbelde haplo1ede populasie uit die kruising 'Kariega X Avocet S' is aangewend om 'n
gedeeltelike koppelingskaart vir die volle stel van 21 koring chromosome saam te stel. Die kaart
het uit 208 DNA merkers, nl., 62 SSR, 133 AFLP, 3 RGA, 10 SRAP merkers en 4 ander lokusse
bestaan. Totale polimorfisme wat deur die verskillende merkersisteme opgespoor is, was as volg:
SSR: 46%, RGA: 9%, AFLP: 7% en SRAP: 6%. Die mate van ontbrekende data was gering
(4%) asook die mate van segregasie distorsie (5%) van 'n enkele geval wat op chromosoom 4A
gekarteer is. 'n Prominente kenmerk van die koppelingskaart is die relatiewe gebrek aan
polimorfiese merkers op die D-genoom, nl., slegs 19% van alle DNA merkers en 11% van alle
AFLP merkers wat slegs 30% van die totale genoom kaartafstand bestaan het. Die stamroes
(Puccinia graminis f. sp. tritici) saailingweerstandsgeen, Sr26, karteer op chromosoom 6A naby
drie SSR merkers. Die geen vir blaartipnekrose, Ltn, karteer op chromosoom 7D. Protokolle vir
SRAP en RGA merkers is ge-optimiseer en gebruik van SRAP merkers in koppelings-analise
word vir die eerste keer in koring gerapporteer.
Die koppelingskaart is in kombinasie met groeikamerdata en gerepliseerde veldproefdata gebruik
om die gene (QTL) vir volwasseplant streeproesweerstand te karteer. Chromosome met statisties
betekenisvolle QTL is met aanvullende SSR merkers geteiken om die resolusie van kartering
verder te verhoog. Die kwaliteit van fenotipiese data, soos in die proewe aangeteken, is bevestig
deur korrelasies te bereken tussen lesings geneem deur onafhanklike plantpataloe (0.799 ± 0.023
vir reaksietipe en 0.942 ± 0.007 vir getransformeerde persentasie blaaroppervlakte besmet).
Hoofeffek QTL vir die twee maatstawwe van weerstand is deur middel van die metodes van
interval QTL kartering en gemodifiseerde interval QTL kartering konsekwent op chromosome
7D (25-48% van variasie verklaar) en 2B (21-46% van variasie verklaar) ge"identifiseer. In
vorige studies is aangetoon dat beide chromosome 7D en 2B QTL vir volwasseplant
streeproesweerstand dra. Die 7D QTL is waarskynlik die weerstandsgeen, Yr 18. QTL met klein
effekte op weerstand is op chromosome lA en 4A ge"identifiseer. Die effek van laasgenoemde
geen was meer prominent in die velddata in die vroee datum van weerstandsbeoordeling. Een
QTL, afkomstig van 'Avocet S', is slegs onder groeikamertoestande identifiseerbaar. Dit dui op
moontlike genotipe-omgewing wisselwerking en beklemtoon die noodsaaklikheid om
aanpassings te maak in groeikamertoestande vir beter simulasie van veldproeftoestande.
Die genetiese grondslag van volwasseplantweerstand teen streeproes in die kultivar 'Kariega' is
deur QTL kartering bepaal. Die 'Kariega X Avocet S' koppelingskaart kan as 'n waardevolle basis
dien vir toekomstige genetiese ontledings van ander polimorfiese kenmerke in die populasie.
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Plastic card frauds, a survey of current relevant card and system properties / Plastkortsystem och brottsmöjligheter, en genomgång av egenskaper hos kort och läsareSavostyanova, Natalia, Velichko, Valeriya January 2004 (has links)
<p>Recently the society has been turning from the use of paper-based technologies to plastic cards in certain spheres of our life. With the emergence and proliferation of high technologies we cannot content with the security provided bypaper only. Therefore the society has chosen plastic to protect its information because it offers far more security based not only on human perception but also on machine-readable elements. </p><p>The number of plastic cards in circulation in different spheres of our everyday life increases constantly. They replace money, documents and allow easy and safe access to some services. In spite of its security the plastic card however is subjected to fraud. </p><p>Plastic card fraud results in significant losses for the various industries. Since the first appearance of plastic cards methods of committing fraud have changed dramatically. Now there is a wide range of high technologies at the disposal of criminals as well as card manufacturers. </p><p>Therefore we have put the great emphasize of this work on the analysis of the most common card technologies in the Plastic Card World, the magnetic stripe and the chip, existing crimes and main means of their committing. And we also have revealed the weak and strong sides of the prevention techniques, which are currently in use.</p>
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Plastic card frauds, a survey of current relevant card and system properties / Plastkortsystem och brottsmöjligheter, en genomgång av egenskaper hos kort och läsareSavostyanova, Natalia, Velichko, Valeriya January 2004 (has links)
Recently the society has been turning from the use of paper-based technologies to plastic cards in certain spheres of our life. With the emergence and proliferation of high technologies we cannot content with the security provided bypaper only. Therefore the society has chosen plastic to protect its information because it offers far more security based not only on human perception but also on machine-readable elements. The number of plastic cards in circulation in different spheres of our everyday life increases constantly. They replace money, documents and allow easy and safe access to some services. In spite of its security the plastic card however is subjected to fraud. Plastic card fraud results in significant losses for the various industries. Since the first appearance of plastic cards methods of committing fraud have changed dramatically. Now there is a wide range of high technologies at the disposal of criminals as well as card manufacturers. Therefore we have put the great emphasize of this work on the analysis of the most common card technologies in the Plastic Card World, the magnetic stripe and the chip, existing crimes and main means of their committing. And we also have revealed the weak and strong sides of the prevention techniques, which are currently in use.
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Effet de l’hôte et de la température sur la structure de la population de Puccinia striiformis f. sp. tritici, agent de la rouille jaune du blé au Moyen Orient / Effect of host and temperature on the population structure of Puccinia striiformis f. sp. tritici, responsible of yellow rust in the Middle EastEl Amil, Rola 25 September 2015 (has links)
L’adaptation des pathogènes à leurs hôtes et aux variations climatiques, particulièrement à la température est étudiée sur l’agent pathogène biotrophe obligatoire responsable de la rouille jaune du blé, Puccinia striiformis f. sp. tritici (Pst) au Moyen Orient. Cette étude s’est déroulée au Liban et en Syrie situés dans le berceau de la région de domestication du blé. Des gènes de résistance spécifique ont été postulés au stade plantule pour 87 lignées élites du programme d’amélioration de l’ICARDA,28 cultivars Libanais, et 23 landraces Libanaises en utilisant 11 pathotypes français disponibles à l’INRA-BIOGER. Un seul gène et une combinaison de gènes ont été postulés dans les lignées elites. Neuf gènes de résistance ont été identifiés dans les lignées élites ; plus de génotypes résistants figuraient parmi les lignées issues du programme d’amélioration. Les landraces sont les plus sensibles mais ont montré une ségrégation de réaction résistance parmi les plants sensibles.Pour la structuration de population pathogène du Liban et de la Syrie, un échantillonnage a été fait dans les deux pays sur du blé tendre, du blé dur et des repousses durant 2010-2011. Six isolats Libanais et 48 isolats Syriens ont été pathotypés avec une gamme de 43 hôtes différentiels. 275 échantillons ont été génotypés avec 20 marqueurs SSR. La population était clonale malgré avec la présence de l’hôte secondaire Berberis sp. dans la région, toutefois un nombre élevé de 50 MLG est observé était pour une population clonale. La présence de la race invasive PstS1/PstS2 caractérise cette région. Le profil de virulence Vr2, 6, 7, 9, 27 est le plus fréquent et typique du groupe génétique Méditerranéen (Bahri et al., 2009). La virulence Vr8 n’est pas fixée dans la population malgré sa présence dans la race invasive décrite depuis l’an 2000 (Milus et al., 2009). L’adaptation de la rouille jaune à la température a été décrite par Milus et al. (2009) et Mboup et al. (2012). Notre étude d’adaptation à la température a été faite sur un échantillon de 26 isolats provenant de zones froides et chaudes avec 4 isolats de référence. Nous avons testé deux paramètres d’agressivité, efficacité d’infection et période de latence sous quatre différents régimes de température (Chaud versus froid pour période de rosée et période d’incubation). Les isolats diffèrent pour leur réponse aux variations de température. Quelques isolats montrent une efficacité d’infection et une courte période de latence sous les différents régimes, d’autres sont efficaces au froid mais pas au chaud et vice versa. Pour l’efficacité d’infection, il n’y a pas d’adaptation mais par contre pour la période de latence on montre une adaptation à la température des isolats de la zone chaude ayant une efficacité d’infection. La température chaude de rosée a retardé la période de latence mais ce phénomène a été moins marqué pour les isolats d’origine chaude quand c’est incubé au chaud. Cette étude a montré que la population est clonale avec un haut nombre de pathotypes. Le germplasme n’est pas diversifié avec des gènes de résistance contre la rouille jaune. L’adaptation de l’agent de la rouille jaune à la température parmi les isolats testés a été décrite pour la période de latence pour les isolats provenant d’origine chaude. / The adaptation of fungal pathogen to its hosts and to the climate variation, in particular to the temperature, was investigated on wheat stripe (yellow) rust, caused by the biotroph fungus Puccinia striiformis f. sp. tritici (Pst) in the Middle East, focusing on Lebanon and Syria. This disease is a major problem for the crop in the region. Specific resistance genes were postulated in 138 wheat genotypes including elite lines, grown varieties and local landraces, using an array of 11 French pathotypes. Resistance gene diversity for yellow rust in wheat elite lines was higher than in current, commercial varieties grown in Lebanon, with nine Yr genes detected singly or in combination. Some varieties were resistant to all tested pathotypes and might provide interesting sources of resistance. Most of the Lebanese landraces were susceptible but also heterogeneous by their number of plants susceptible and resistant to a specific pathotype in a same landrace.A field survey was conducted in Lebanon and Syria in 2010-2011 and 275 Pst isolates were collected. The pathogen population was genotyped with 20 microsatellite markers and was found to be clonal, although the alternate host Berberis libanotica is present in the region. The dominant multilocus genotype shared similarity with the new invasive strain PstS1/PstS2 dispersed worldwide since 2000. The population was clonal with 10 pathotypes detected in Lebanon and Syria. 50 MLGs were detected considered high for clonal population. The virulence profiles combining Vr2, Vr6, Vr7, Vr9, and Vr27 are typical of the Mediterranean area according to group (Bahri et al., 2009) and corresponded to the worldwide invasive pathotype described since 2000 (Milus et al., 2009). The Vr8 was not fixed in this population, whereas this virulence is frequent in the Mediterranean genetic group (Bahri et al., 2009).Recently Pst strains have been described for adaptation to warm temperature (Milus et al., 2009; Mboup et al., 2012). The question of temperature adaptation in this study was whether the strains adapted to warm temperature are found in few clones of invasive strains or if they are selected in different pathogen genotypes locally under specific climate conditions. We selected 26 Pst isolates from the Middle East, 13 isolates from warm and 13 isolates from cold areas. We assessed their infection efficiency and latent period under four temperature regimes (high and warm temperature for the spore penetration phase, and high and warm temperature for the latency period). The isolates differed for the thermal aptitude for infection efficiency and latent period, but no clear relationship was established between the climate of the origin location of the isolate and its thermal aptitude. Some isolates were able to infect at high temperature but had long latency at high temperature and vice versa, some isolates had low infection efficiency and short latent period at high temperature, and few isolates were efficient either at high temperature or cold temperature for infection efficiency. Latency period showed pattern of local adaptation. Warm dew temperatures retarded sporulation, but this effect was far less marked for isolates from warm climates when incubated under warm conditions.This study provides details about probable effective yellow rust genes present in different genotypes and the prevalent pathotypes in the region. Moreover, the thermal aptitude for infection efficiency and latent period of some isolates under contrasting temperature will help us to build a better integrated disease management in the highlight of global warming.
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Prekonavani barier / Overcoming the barriersKudelová, Barbora January 2017 (has links)
Showing the barriers in the city, which inhibit a human in its movement along the landscape. Bunch of barriers at one place can signify a problem for a human to overcome. Marking these places is also showed below the prize map which illustrates from the economic point of view the problem exists at that place and the place is not that permeable as it should be. After marking the problematic spaces and their overlook in the real world there follows a choice of one place and its particular solution. Verifying the reasons why overcoming especially this place, what are the reasons for connecting it, analysing the areas on both sides, pointing out the place of connection and the way to solve the pedestrian bridge and finding the conceptual principle which is the support for the construction principle.
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Virus-induced gene silencing of putative Diuraphis noxia (Kurdjumov) resistance genes in wheatStarkus, Laura January 1900 (has links)
Master of Science / Department of Entomology / C. Michael Smith / The Russian wheat aphid Diuraphis noxia (Kurdjumov) is a serious pest of world cereal grain crops, primarily barley and wheat. A phenotypic characteristic of D. noxia feeding, leaf rolling, creates a leaf pseudo gall which protects aphids, making it difficult to treat infested plants with insecticides or biological control agents. Therefore, the use of D. noxia-resistant crops is a desirable aphid management tactic. Because of the development of virulent D. noxia biotypes, the identification of new sources of barley and wheat resistance is necessary. Virus-induced gene silencing (VIGS) utilizes the plant defense system to silence viruses in inoculated plants. The accumulation of virus RNA in plants triggers the defense system to silence sequences homologous to the introduced virus and sequences of interest from a plant are inserted into the virus and silenced along with the virus. The VIGS method was tested to determine the ability of barley stripe mosaic virus (BSMV) to serve as a VIGS vector in wheat plants containing the Dnx gene for resistance to D. noxia. Dnx leaves with silenced BSMV virus yielded D. noxia populations that were significantly no different from populations produced on healthy Dnx leaves. Thus, BSMV silencing does not interfere with Dnx resistance. Several different methods were examined to determine how best to confine aphids to the silenced leaf, and a modified plastic straw cage was chosen as the optimum cage type. Microarray and gene expression data were analyzed to select two NBS-LRR type disease resistance protein genes - TaAffx.104814.1.S1_at and TaAffx.28897.1.S1 - (NBS-LRR1 and NBSLRR2), in order to assess their role in Dnx resistance. NBS-LRR1 and NBSLRR2 were silenced by inoculating leaves of Dnx plants with barley stripe mosaic virus (BSMV) containing sequences of each gene. Controls included Dnx and Dn0 plants inoculated with BSMV and non-BSMV inoculated plants. Aphids were allowed to feed on control and treatment plants to assess aphid population and
mean weight of aphids surviving at the end of the experiment. There were no differences among treatments based on aphid population, but there were significant differences the mean weights of aphids reared on several different treatments.
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Qualitätserkennung am Apfel mit Hilfe der StreifenprojektionHother, Katrin 17 June 1998 (has links)
Äpfel müssen für die Verwendung als Tafelobst in einen den Handelsgütebestimmungen entsprechenden Zustand aufbereitet werden. Die Anforderungen an die Äpfel der einzelnen Klassen sind in den Qualitätsnormen und Handelsklassen für die EG festgelegt. Automatische Verfahren zur Sortierung von Äpfeln nach Größe, Farbe und Form kommen zum Einsatz. Qualitätsfehler auf der Apfeloberfläche ohne Farbveränderungen der Fruchtoberfläche werden nicht erkannt. Ausgehend von der auf dem Markt vorhandenen Sortiertechnik für Obst und Gemüse sowie den aktuellen technischen Möglichkeiten der Oberflächenerkennung bzw. -prüfung wurde nach einer Lösung gesucht, auch unverfärbte Oberflächenformveränderungen zu erkennen. Unverfärbte Oberflächenformveränderungen sind häufig die Ursache von größeren, oft infektiösen Schadstellen nach der Apfelaufbereitung. Sie führen zu Ausfällen für die Erzeuger und den Handel. Verbraucherbefragungen ergaben Interesse für den Handel an einer Erkennung unverfärbter Oberflächenformveränderungen zur Qualitätsverbesserung des Marktangebotes. Dabei sind breite flache, breite tiefe und tiefe schmale unverfärbte Oberflächenformveränderungen von besonderem Interesse. Nach bisher vorliegenden Untersuchungsergebnissen können mit Hilfe des Reflexionsmeßverfahrens Qualitätsfehler erkannt werden, die mit Verfärbung der Schale oder des schalennahen Fruchtfleisches einhergehen. Für die Erkennung von Druckstellen, die nicht mit Verfärbung verbunden sind, ist das Reflexionsmeßverfahren daher nur bedingt geeignet. Zur Problemlösung wurde ein Versuchsstand für Triangulationsmessungen mit Liniengitterprojektion aufgebaut. Es wurden 900 Apfelstreifenbilder der Apfelsorten "Golden Delicious", "Red Delicious" und "Braeburn" mit Hilfe des Versuchsaufbaus und dem zur Bilderkennung entwickelten Erkennungsalgorithmus untersucht. Zur Gewinnung der Merkmale aus dem Streifenbild wurde auf die Anzahl bzw. die Abstände der Streifen zurückgegriffen. Die aufgenommenen Apfelstreifenbilder wurden durch den Erkennungsalgorithmus in die Merkmalsklassen "gesunde Oberfläche", "Stiel- und Kelchgrube" und "Druckstelle" gruppiert. Nach den erfolgten Untersuchungen ist das Streifenprojektionsverfahren für die Sortierprozesse von Fruchtoberflächen geeignet, wenn die effektive optische Auflösung des Gesamtsystems, die von der Paßfähigkeit der Rastergrößen der einzelnen Baugruppen des Systems (Streifengitter, Kamerachip, Bildspeicher) abhängt, angepaßt werden kann (Ausschalten störender Moiré-Effekte im erforderlichen Auflösungsbereich). Die dreidimensionale Oberflächenkontur des Apfels moduliert das Abbild der projizierten Streifen, wodurch dreidimensionale Informationen der Oberflächentopographie in einem zweidimensionalen Bild impliziert werden können. Unverfärbte Oberflächenformveränderungen sind mit dem beschriebenen Erkennungsalgorithmus zu klassifizieren. Der Einsatz der Bilderkennung in dieser zeitkritischen Anwendung kann nur hardware-orientiert gelöst werden. Ein prinzipieller funktionsfähiger Lösungsansatz ist mit dem Erkennungsalgorithmus geschaffen. / Apples must conform to the trade quality regulations to be deemed fit for consumption. The EU requirements for each individual class of apple are specified in quality standards and trade classifications. Automatic processes are used to sort apples by size, colour and shape. Non-discoloured surface discrepancies of the fruit are not identified. This paper aims to find a system which allows non-discoloured surface discrepancies based on the sorting method for fruit and vegetables available on the market and state-of-the-art technology. Non-discoloured surface discrepancies often caused by serious, and in many cases, infectious areas of damage after the apples are processed. They result in losses for the grower and the trade. Consumer research revealed trade interest in a system which could identify non-discoloured surface discrepancies, leading to an increase in the quality of goods supplied to the market. Broad shallow, broad deep and shallow narrow non-discoloured discrepancies are of particular relevance. Previous studies have shown that discoloured discrepancies (discrepancies involving discoloration of the skin, or the fruit tissue immediately below the skin) can be identified using reflection measurement procedures. Such procedures have limited applicability for evaluating bruises which do not result in skin discoloration. An experiment bench was constructed for triangulation readings of projected line patterns in an attempt to solve this problem. Altogether 900 stripe images of apples of the "Golden Delicious", "Red Delicious" and "Braeburn" varieties were analysed using the experiment design and the algorithm developed for evaluating the images. The characteristics of the stripe image were determined on the basis of the number of stripes, or the spacing between the stripes. The recorded apple stripe images were grouped into the following characteristic categories by the evaluation algorithm: "healthy surface", "stalk and calyx" and "bruise". The study shows that the stripe projection procedure is suitable for sorting fruit by surface quality if the effective optical resolution of the overall system can be adapted accordingly (i.e. if the interfering Moiré effects can be eliminated in the required resolution range). This resolution depends on the grid sizes of individual system components (stripe pattern, camera chip, image memory). The three-dimensional contours of the apple surface alter the reflection of the projected stripes, which allows three-dimensional information regarding the surface topography to be indicated in a two-dimensional image. Non-discoloured surface discrepancies may be classified with the evaluation algorithm described above. The only viable method of applying image evaluation procedures requires substantial hardware. The evaluation algorithm is one solution which functions in principle.
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