48 resultados para Center for Night Vision
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Vision affords us with the ability to consciously see, and use this information in our behavior. While research has produced a detailed account of the function of the visual system, the neural processes that underlie conscious vision are still debated. One of the aims of the present thesis was to examine the time-course of the neuroelectrical processes that correlate with conscious vision. The second aim was to study the neural basis of unconscious vision, that is, situations where a stimulus that is not consciously perceived nevertheless influences behavior. According to current prevalent models of conscious vision, the activation of visual cortical areas is not, as such, sufficient for consciousness to emerge, although it might be sufficient for unconscious vision. Conscious vision is assumed to require reciprocal communication between cortical areas, but views differ substantially on the extent of this recurrent communication. Visual consciousness has been proposed to emerge from recurrent neural interactions within the visual system, while other models claim that more widespread cortical activation is needed for consciousness. Studies I-III compared models of conscious vision by studying event-related potentials (ERP). ERPs represent the brains average electrical response to stimulation. The results support the model that associates conscious vision with activity localized in the ventral visual cortex. The timing of this activity corresponds to an intermediate stage in visual processing. Earlier stages of visual processing may influence what becomes conscious, although these processes do not directly enable visual consciousness. Late processing stages, when more widespread cortical areas are activated, reflect the access to and manipulation of contents of consciousness. Studies IV and V concentrated on unconscious vision. By using transcranial magnetic stimulation (TMS) we show that when early visual cortical processing is disturbed so that subjects fail to consciously perceive visual stimuli, they may nevertheless guess (above chance-level) the location where the visual stimuli were presented. However, the results also suggest that in a similar situation, early visual cortex is necessary for both conscious and unconscious perception of chromatic information (i.e. color). Chromatic information that remains unconscious may influence behavioral responses when activity in visual cortex is not disturbed by TMS. Our results support the view that early stimulus-driven (feedforward) activation may be sufficient for unconscious processing. In conclusion, the results of this thesis support the view that conscious vision is enabled by a series of processing stages. The processes that most closely correlate with conscious vision take place in the ventral visual cortex ~200 ms after stimulus presentation, although preceding time-periods and contributions from other cortical areas such as the parietal cortex are also indispensable. Unconscious vision relies on intact early visual activation, although the location of visual stimulus may be unconsciously resolved even when activity in the early visual cortex is interfered with.
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This doctoral thesis was published in printed form in 1987. It was digitized from paper copy in 2013. Unfortunately on some pages the digitizaion process has not been complete, i.e there are some minor typographic erros on some pages.
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The papermaking industry has been continuously developing intelligent solutions to characterize the raw materials it uses, to control the manufacturing process in a robust way, and to guarantee the desired quality of the end product. Based on the much improved imaging techniques and image-based analysis methods, it has become possible to look inside the manufacturing pipeline and propose more effective alternatives to human expertise. This study is focused on the development of image analyses methods for the pulping process of papermaking. Pulping starts with wood disintegration and forming the fiber suspension that is subsequently bleached, mixed with additives and chemicals, and finally dried and shipped to the papermaking mills. At each stage of the process it is important to analyze the properties of the raw material to guarantee the product quality. In order to evaluate properties of fibers, the main component of the pulp suspension, a framework for fiber characterization based on microscopic images is proposed in this thesis as the first contribution. The framework allows computation of fiber length and curl index correlating well with the ground truth values. The bubble detection method, the second contribution, was developed in order to estimate the gas volume at the delignification stage of the pulping process based on high-resolution in-line imaging. The gas volume was estimated accurately and the solution enabled just-in-time process termination whereas the accurate estimation of bubble size categories still remained challenging. As the third contribution of the study, optical flow computation was studied and the methods were successfully applied to pulp flow velocity estimation based on double-exposed images. Finally, a framework for classifying dirt particles in dried pulp sheets, including the semisynthetic ground truth generation, feature selection, and performance comparison of the state-of-the-art classification techniques, was proposed as the fourth contribution. The framework was successfully tested on the semisynthetic and real-world pulp sheet images. These four contributions assist in developing an integrated factory-level vision-based process control.
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Today lean-philosophy has gathered a lot of popularity and interest in many industries. This customer-oriented philosophy helps to understand customers value creation which can be used to improve efficiency. A comprehensive study of lean and lean-methods in service industry were created in this research. In theoretical part lean-philosophy is studied in different levels which will help to understand its diversity. To support lean, this research also presents basic concepts of process management. Lastly theoretical part presents a development model to support process development in systematical way. The empirical part of the study was performed by performing experimental measurements during the service centers product return process and by analyzing this data. Measurements were used to map out factors that have a negative influence on the process flow. Several development propositions were discussed to remove these factors. Problems mainly occur due to challenges in controlling customers and due to the lack of responsibility and continuous improvement on operational level. Development propositions concern such factors as change in service centers physical environment, standardization of work tasks and training. These factors will remove waste in the product return process and support the idea of continuous improvement.
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Poster at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014
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Tool center point calibration is a known problem in industrial robotics. The major focus of academic research is to enhance the accuracy and repeatability of next generation robots. However, operators of currently available robots are working within the limits of the robots repeatability and require calibration methods suitable for these basic applications. This study was conducted in association with Stresstech Oy, which provides solutions for manufacturing quality control. Their sensor, based on the Barkhausen noise effect, requires accurate positioning. The accuracy requirement admits a tool center point calibration problem if measurements are executed with an industrial robot. Multiple possibilities are available in the market for automatic tool center point calibration. Manufacturers provide customized calibrators to most robot types and tools. With the handmade sensors and multiple robot types that Stresstech uses, this would require great deal of labor. This thesis introduces a calibration method that is suitable for all robots which have two digital input ports free. It functions with the traditional method of using a light barrier to detect the tool in the robot coordinate system. However, this method utilizes two parallel light barriers to simultaneously measure and detect the center axis of the tool. Rotations about two axes are defined with the center axis. The last rotation about the Z-axis is calculated for tools that have different width of X- and Y-axes. The results indicate that this method is suitable for calibrating the geometric tool center point of a Barkhausen noise sensor. In the repeatability tests, a standard deviation inside robot repeatability was acquired. The Barkhausen noise signal was also evaluated after recalibration and the results indicate correct calibration. However, future studies should be conducted using a more accurate manipulator, since the method employs the robot itself as a measuring device.
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I den frsta delen av den hr avhandlingen presenteras en bildens genealogi. Den skildrar hur begreppen fr bilden, seendet och jaget utvecklades i relation till varandra i en specifik vetenskaplig och filosofisk kontext. Berttelsen strcker sig frn den tidiga renssansen och det perspektivistiska mleriet, till fotografiets fdelse och positivismen. Den hr utvecklingen medfrde en form av reduktionism i vilken jagets roll betydelsen av den mnskliga psykologin, vrt omdme, vr uppmrksamhet och vr vilja blev frbisedd. Inom den hr tanketraditionen uppstod en frskjutning, frn en frstelse av bilden som en representation av det tredimensionella rummet p en tvdimensionell yta, till en uppfattning om bilden som en genomskinlig ruta, ett fnster ut mot vrlden. Idn om avbildningen som en neutral blick frn ingenstans kom att frstrka en skeptisk hllning till kommunikation, dialog och vittnesml och drmed ven undergrva vr tillit till varandra och fljaktligen vr tillit till oss sjlva. I den andra delen erbjuder frfattaren ett alternativ till den tanketradition som behandlas i den frsta delen. Det som blev frbisett i uppfattningen om en blick frn ingenstans var att bilden r ett hjlpmedel d vi bearbetar vrt synflt. Bilden hjlper oss att dela vr syn p saker. Genom den hr uppgiften av att dela blir bilden riktningsgivande i vra frsk att orientera oss i vrlden. Jag kan st bredvid en annan mnniska och se vad hon ser, men jag vet inte ndvndigtvis hur hon uppfattar det vi ser. Bilden lgger till ett led i det hr frhllandet eftersom den inte enbart visar vad den andra ser. Nr bilden fungerar som den skall visar den ocks hur den andra ser och p det hr sttet blir bilden verksam. Den freliggande avhandlingen kombinerar epistemologi med vetenskapshistoria och visuella kulturstudier, men dess huvudintresse r filosofiskt. Den befattar sig med filosofiska missfrstnd angende avbildning som en mimetisk konstform, kunskap som domesticering och varseblivning som mottagning av data. ------------------------------------------------------ Tmn vitskirjan ensimminen osa selvitt kuvaksitteen genealogiaa. Se havainnollistaa miten kuvan, nkemisen ja minn ksitteet kehittyivt suhteessa toisiinsa. Kertomus ulottuu varhaisesta renessanssista ja perspektivistisest maalaustaiteesta, positivismin aikakauteen ja valokuvan syntyyn. Tm kehitys toi mukanaan reduktionismin jossa minn rooli ihmisen psykologian merkitys, meidn arviointikyky, meidn huomiokyky sek meidn tahtomme vaipui unohduksiin. Ajatusmaailmassa tapahtui siirtym, kuvan merkitys vaihtui ksityksest jossa se on kolmiulotteisen tilan representaatio kaksiulotteisella pinnalla, ksitykseen jossa kuva on lpinkyv ruutu, ikkuna kohti maailmaa. Ajatus kuvasta neutraalin nkkulman kantajana vahvisti skeptist suhtautumista kommunikaatiota, dialogisuutta ja subjektiivisuutta kohtaan. Tm skeptisyys ilmentyi mys vahvana epluottamuksena ihmiskeskeisyytt ja toiseutta kohtaan. Toisessa osassa tekij tarjoaa vaihtoehdon tlle skeptiselle ajatusmaailmalle jota tarkastellaan ensimmisess osassa. Kuva on mys vline joka auttaa meit jsentmn meidn nkkenttmme. Se auttaa meit jakamaan meidn ksityksi toistemme kanssa. Tm nkemisen jakamisen kytnt on kuvan keskeinen tehtv. Voin seist toisen ihmisen vieress ja nhd samat asiat kuin hn, mutta en vlttmtt ymmrr miten hn nkee nm asiat. Kuva lis jotain olennaista thn suhteeseen. Kun kuva toimii niin kun sen kuuluu toimia, se nytt mys miten toinen nkee, tll tavalla kuvasta tulee vlittj. Tm vitskirja yhdist epistemologiaa, tieteen historiaa ja visuaalisen kulttuurin tutkimusta, mutta sen pasiallinen tavoite on filosofinen. Se ksittelee filosofisia vrinksityksi koskien kuvan eideettisyytt.
Resumo:
This thesis studies the use of machine vision in RDF quality assurance and manufacturing. Currently machine vision is used in recycling and material detection and some commer- cial products are available in the market. In this thesis an on-line machine vision system is proposed for characterizing particle size. The proposed machine vision system is based on the mapping between image segmenta- tion and the ground truth of the particle size. The results shows that the implementation of such machine vision system is feasible.
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Kanadalaisen kirjailijan L. M. Montgomeryn tunnetun ja rakastetun Anna-sarjan ensimminen osa Anne of Green Gables -teos (1908) kertoo orvosta tytst, joka psee Prinssi Edwardin saaren Avonlean kyln asumaan naimattoman sisarusparin Marilla ja Matthew`n kasvattilapseksi. Luonto on keskeisell sijalla teoksessa: Anna on luontoa rakastava ja luonnon keskell viihtyv tytt ja mys teoksen kertoja kuvaa paljon luontoa. Tutkimukseni ksittelee luontoa Anne of Green Gables -teoksessa. Tutkin luontoteemaa teoksessa seuraavista nkkulmista: Analysoin, kuinka luonto kuvataan teoksessa ja millainen on teoksen luontokuva. Luontokuvaa ksittelen pastoraalin ksitteen kautta, ja kysyn teokselta, voidaanko se tulkita pastoraaliksi ja kuinka teos asettuu pastoraalin traditioon. Lisksi erittelen, millainen on phenkiln Annan luontosuhde. Millaisen arvon hn antaa luonnolle ja mit merkityksi hn liitt luontoon? Tutkimus asettuu ekokriittiseen viitekehykseen, ja pohdin mys sit, minklainen on teoksen representaatio luonnosta ekokriittisesti tarkastellen. Amerikkalaisen transsendentalistin Ralph Waldo Emersonin luontofilosofia kulkee mys taustajuonteena tutkielmassa ja erittelen, mit yhtymkohtia hnen luontofilosofiassaan on Anne of Green Gables -teokseen. Anne of Green Gables -teoksen luontokuvaa voidaan luonnehtia romantisoiduksi ja idealisoivaksi. Luonto kuvataan kauniiksi, ja sen kauneutta ylist niin Anna kuin teoksen kaikkitietv kertojakin. Teoksen luontokuva on pastoraalinen, sill siin esiintyy vahvasti pastoraaliin liittyv diskurssi maaseudun ja kaupungin vastakkainasettelusta siten, ett maaseutu assosioituu positiivisesti, kun taas kaupunki nhdn negatiivisessa valossa. Luonnonlheinen Avonlean kyl nyttytyy teoksessa niin idealisoidussa valossa, ett se muistuttaa jo jonkinlaista myyttist paratiisia. Nin ollen teoksen pastoraalisuus saa pejoratiivisiakin piirteit. Annan luontosuhdetta vritt voimakas kunnioitus ja arvostus luontoa kohtaan. Hnen luontoon liittmist arvoista keskeiselle sijalle nousee luonnon kauneus. Luonnon kauneuden arvostaminen toimii kuitenkin porttina luonnon toiseuttamiseen, mist syntyy pieni arvoristiriita. Toisaalta kuitenkin Anna samaistuu luontoon tavalla, joka hmrt perinteist subjektiobjekti-dikotomiaa. Anna nyttytyy vihren maailman arkkityyppin, lapsena, joka sulautuu luontoon ja kokee sen kodikseen. Luonto edustaa Annalle vapautta ja hertt mys hnen mielikuvituksena ja taiteellisen inspiraation. Lisksi luonto on Annalle paikka, jossa voi saavuttaa autenttisen yhteyden Jumalaan.
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Internationalization represents a complex topic that has been researched for quite some time. However, since it continues to be extremely current a topic, its significance has not diminished, but maybe even increased in importance. Companies today face extreme pressure to enter new markets in the hope of growing, becoming more profitable, increasing market share, attracting new customers and meeting the requirements of its share- and stakeholders. In the increasingly global business environment of today, companies are facing both challenges and possible advantages of internationalization. Few companies are not operating internationally and it is becoming the question of Why not? rather than Why? to internationalize business operations. Internationalization and the importance of strategy are discussed in this research from the viewpoint of three case companies that were interviewed about internationalization strategies. This research project is a qualitative study that answers the research question of How is a business strategy constructed for entering a new market? The sub-questions are How are goals set and what indicators are used to monitor the achievement of these goals? What are the key characteristics of a strategy implementation process? The research method chosen for this study is a multiple-case study. Three case companies were chosen for the interviews in order to gain in-depth data of internationalization strategies within the construction industry.
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Kandidaatinty tehtiin osana PulpVision-tutkimusprojektia, jonka tarkoituksena on kehitt kuvapohjaisia laskenta- ja luokittelumetodeja sellun laaduntarkkailuun paperin valmistuksessa. Tmn tutkimusprojektin osana on aiemmin kehitetty metodi, jolla etsittiin kaarevia rakenteita kuvista, ja tt metodia hydynnettiin kuitujen etsintn kuvista. Tt metodia kytettiin lhtkohtana kandidaatintylle. Tyn tarkoituksena oli tutkia, voidaanko erilaisista kuitukuvista laskettujen piirteiden avulla tunnistaa kuvassa olevien kuitujen laji. Niss kuitukuvissa oli kuituja neljst eri puulajista ja yhdest kasvista. Nm lajit olivat akasia, koivu, mnty, eukalyptus ja vehn. Jokaisesta lajista valittiin 100 kuitukuvaa ja nm kuvat jaettiin kahteen ryhmn, joista ensimmist kytettiin opetusryhmn ja toista testausryhmn. Opetusryhmn avulla jokaiselle kuitulajille laskettiin nit kuvaavia piirteit, joiden avulla pyrittiin tunnistamaan testausryhmn kuvissa olevat kuitulajit. Nm kuvat oli tuottanut CEMIS-Oulu (Center for Measurement and Information Systems), joka on mittaustekniikkaan keskittynyt yksikk Oulun yliopistossa. Yksittiselle opetusryhmn kuitukuvalle laskettiin keskiarvot ja keskihajonnat kolmesta eri piirteest, jotka olivat pituus, leveys ja kaarevuus. Lisksi laskettiin, kuinka monta kuitua kuvasta lydettiin. Niden piirteiden eri yhdistelmien avulla testattiin tunnistamisen tarkkuutta kyttmll k:n lhimmn naapurin menetelm ja Naiivi Bayes -luokitinta testausryhmn kuville. Testeist saatiin lupaavia tuloksia muun muassa pituuden ja leveyden keskiarvoja kytettess saavutettiin jopa noin 98 %:n tarkkuus molemmilla algoritmeilla. Tunnistuksessa kuitujen keskimrinen pituus vaikutti olevan kuitukuvia parhaiten kuvaava piirre. Kytettyjen algoritmien vlill ei ollut suurta vaihtelua tarkkuudessa. Testeiss saatujen tulosten perusteella voidaan todeta, ett kuitukuvien tunnistaminen on mahdollista. Testien perusteella kuitukuvista tarvitsee laskea vain kaksi piirrett, joilla kuidut voidaan tunnistaa tarkasti. Kytetyt lajittelualgoritmit olivat hyvin yksinkertaisia, mutta ne toimivat testeiss hyvin.
