Accuracy of direct digital radiography for detecting occlusal caries in primary teeth compared with conventional radiography and visual inspection: an in vitro study

Objectives: The diagnosis of caries lesions is still a matter of concern in dentistry. The diagnosis of dental caries by digital radiography has a number of advantages over conventional radiography; however, this method has not been explored fully in the field of paediatric dentistry. This in vitro research evaluated the accuracy of direct digital radiography compared with visual inspection and conventional radiography in the diagnosis of occlusal caries lesions in primary molars. Methods: 50 molars were selected and evaluated under standardized conditions by 2 previously calibrated examiners according to 3 diagnostic methods (visual inspection, conventional radiography and direct digital radiography). Direct digital radiographs were obtained with the Dixi3 system (Planmeca, Helsinki, Finland) and the conventional radiographs with InSight film (Kodak Eastman Co., Rochester, NY). The images were scored and a reference standard was obtained histologically. The interexaminer reliability was calculated using Cohen`s kappa test and the specificity, sensitivity and accuracy of the methods were calculated. Results: Examiner reliability was good. For lesions limited to the enamel, visual inspection showed significantly higher sensitivity and accuracy than both radiographic methods, but no significant difference was found in specificity. For teeth with dentinal caries, no significant differences were found for any parameter when comparing visual and radiographic evaluation. Conclusions: Although less accurate than the visual method for detecting caries lesions confined to the enamel, the direct digital radiographic method is as effective as conventional radiographic examination and visual inspection of primary teeth with occlusal caries when the dentine is involved. Dentomaxillofacial Radiology (2010) 39, 362-367. doi: 10.1259/dmfr/22865872

Digital-domain self-calibration technique for video-rate pipeline A/D converters using Gaussian white noise

Electronics Letters Vol.38, nº 19

Minimal computation structures for visual information applications based on printed electronics

In the early nineties, Mark Weiser wrote a series of seminal papers that introduced the concept of Ubiquitous Computing. According to Weiser, computers require too much attention from the user, drawing his focus from the tasks at hand. Instead of being the centre of attention, computers should be so natural that they would vanish into the human environment. Computers become not only truly pervasive but also effectively invisible and unobtrusive to the user. This requires not only for smaller, cheaper and low power consumption computers, but also for equally convenient display solutions that can be harmoniously integrated into our surroundings. With the advent of Printed Electronics, new ways to link the physical and the digital worlds became available. By combining common printing techniques such as inkjet printing with electro-optical functional inks, it is starting to be possible not only to mass-produce extremely thin, flexible and cost effective electronic circuits but also to introduce electronic functionalities into products where it was previously unavailable. Indeed, Printed Electronics is enabling the creation of novel sensing and display elements for interactive devices, free of form factor. At the same time, the rise in the availability and affordability of digital fabrication technologies, namely of 3D printers, to the average consumer is fostering a new industrial (digital) revolution and the democratisation of innovation. Nowadays, end-users are already able to custom design and manufacture on demand their own physical products, according to their own needs. In the future, they will be able to fabricate interactive digital devices with user-specific form and functionality from the comfort of their homes. This thesis explores how task-specific, low computation, interactive devices capable of presenting dynamic visual information can be created using Printed Electronics technologies, whilst following an approach based on the ideals behind Personal Fabrication. Focus is given on the use of printed electrochromic displays as a medium for delivering dynamic digital information. According to the architecture of the displays, several approaches are highlighted and categorised. Furthermore, a pictorial computation model based on extended cellular automata principles is used to programme dynamic simulation models into matrix-based electrochromic displays. Envisaged applications include the modelling of physical, chemical, biological, and environmental phenomena.

Coupling digital and physical worlds in an AR magic show performance: lessons learned

“Magic for a Pixeloscope” is a one hour show conceived to berepresented in a theater scenario that merges mixed and augmented reality (MR/AR) and full-body interaction with classical magic to create new tricks. The show was conceived by an interdisciplinary team composed by a magician, twointeraction designers, a theater director and a stage designer. Themagician uses custom based hardware and software to createnew illusions which are a starting point to explore new languagefor magical expression. In this paper we introduce a conceptualframework used to inform the design of different tricks; weexplore the design and production of some tricks included in theshow and we describe the feedback received on the world premiere and some of the conclusions obtained.

Calibration of a desktop scanner and digital image analysis procedure for quantification of a root morphology

Selostus: Tasoskannerin ja digitaalisen kuva-analyysimenetelmän kalibrointi juurten morfologian kvantifioimiseksi

The Gaussian assumption in second-order estimation problems in digital communications

This paper deals with the goodness of the Gaussian assumption when designing second-order blind estimationmethods in the context of digital communications. The low- andhigh-signal-to-noise ratio (SNR) asymptotic performance of the maximum likelihood estimator—derived assuming Gaussiantransmitted symbols—is compared with the performance of the optimal second-order estimator, which exploits the actualdistribution of the discrete constellation. The asymptotic study concludes that the Gaussian assumption leads to the optimalsecond-order solution if the SNR is very low or if the symbols belong to a multilevel constellation such as quadrature-amplitudemodulation (QAM) or amplitude-phase-shift keying (APSK). On the other hand, the Gaussian assumption can yield importantlosses at high SNR if the transmitted symbols are drawn from a constant modulus constellation such as phase-shift keying (PSK)or continuous-phase modulations (CPM). These conclusions are illustrated for the problem of direction-of-arrival (DOA) estimation of multiple digitally-modulated signals.

Statistical reference criteria for adaptive signal processing in digital communications

A general criterion for the design of adaptive systemsin digital communications called the statistical reference criterionis proposed. The criterion is based on imposition of the probabilitydensity function of the signal of interest at the outputof the adaptive system, with its application to the scenario ofhighly powerful interferers being the main focus of this paper.The knowledge of the pdf of the wanted signal is used as adiscriminator between signals so that interferers with differingdistributions are rejected by the algorithm. Its performance isstudied over a range of scenarios. Equations for gradient-basedcoefficient updates are derived, and the relationship with otherexisting algorithms like the minimum variance and the Wienercriterion are examined.

Sähköpostimyynnin erityispiirteet taloushallinnon näkökulmasta Case: Sanoma Magazines Finland Oy

Digitaalisten myyntikanavien käytön lisääntyminen suoramarkkinoinnissa ja kanavien tarjoamat mahdollisuudet ovat ajankohtainen aihe yritysmaailmassa. Digitalisoitumisen hyödyt yritykselle ovat myös uusi tutkimuskohde. Tutkimuksessa pyritään löytämään perinteisen ja digitaalisen kanavan erot sekä kuvaamaan sähköpostimyynnin erityispiirteet aikakauslehden tilausmyynnissä. Tutkimuksen näkökulmana on taloushallinnon kustannus-hyötytarkastelu. Tämän kvalitatiivisen tutkimuksen menetelmänä on tapaustutkimus ja kohdeyrityksenä Sanoma Magazines Finland Oy, jonka lehtituotteiden myynnin tietoja on kerätty pääasiassa havainnoimalla yrityksen eri järjestelmistä. Ilmiötä on tarkasteltu sähköiseen markkinointiin liittyvän lainsäädännön, strategia-ajattelun käsitteistön ja taloushallinnosta erityisesti kustannuslaskennan kautta. Empiriassa kuvataan kahden eri myyntikanavan myyntiprosessit. Vertailemalla eri kanavien viiden eri lehtituotteen kahden vuoden myynnin toimenpiteiden tunnuslukuja keskenään pyritään selvittämään ja kuvaamaan sähköpostimyynnin erityispiirteet.

Factors Affecting Consumer’s Illicit Purchase of Copyrighted Digital Work

Peer-to-Peer (P2P) technology has revolutionized file exchange activities besides enhancing processing power distribution. As such, this technology which is nowadays made freely available to all internet users also imposes a threat as it enables the illegal distribution of copyrighted digital work. P2P technology continuously evolves in a greater pace than copyright legislation, leading to compatibility gaps between the applicability of copyright law and the illicit file sharing and downloading. Such issues give high incentives to consumers to practise piracy using P2P systems with a low perception of risk towards prosecution, leading to substantial losses for copyright owners. This study focuses on developing insights for content owners on consumer behaviour towards piracy in Finland, where quantitative analyses are assessed using a data set based on a survey conducted by the Helsinki Institute for IT. The research approach investigates the significance of three fundamental areas in relation to evaluate consumer behaviour as: environmental-related factors, innovation-related factors and consumer-related. each of these are integrates concepts derived in previous theoretical models such as the technology acceptance model, theory of reasoned action, theory of planned behaviour, the issue-risk-judgement model and the Hunt & Vitell’s model.

Development of Russian Ports in The Gulf of Finland

Russia has been one of the fastest developing economic areas in the world. Based on the GDP, the Russian economy grew evenly since the crisis in 1998 up till 2008. The growth in the gross domestic product has annually been some 5–10%. In 2007, the growth reached 8.1%, which is the highest figure after the 10% growth in 2000. Due to the growth of the economy and wage levels, purchasing power and consumption have been strongly increasing. The growing consumption has especially increased the imports of durables, such as passenger cars, domestic appliances and electronics. The Russian ports and infrastructure have not been able to satisfy the growing needs of exports and imports, which is why quite a large share of Russian foreign trade is going through third countries as transit transports. Finnish ports play a major role in transit transports to and from Russia. About 15% of the total value of Russian imports was transported through Finland in 2008. The economic recession that started in autumn 2008 and continues to date has had an impact on the economic development of Russia. The export income has decreased, mainly due to the reduced world market prices of energy products (oil and gas) and raw minerals. Investments have been postponed, getting credit is more difficult than before, and the ruble has weakened in relation to the euro and the dollar. The imports are decreasing remarkably, and are not forecast to reach the 2008 volumes even in 2012. The economic crisis is reflected in Finland's transit traffic. The volume of goods transported through Finland to and from Russia has decreased almost in the same proportion as the imports of goods to Russia. The biggest risk threatening the development of the Russian economy over long term is its dependence on export income from oil, gas, metals, minerals and forest products, as well as the trends of the world market prices of these products. Nevertheless, it is expected that the GDP of Russia will start to grow again in the forthcoming years due to the increased demand for energy products and raw minerals in the world. At the same time, it is obvious that the world market prices of these products will go up with the increasing demand. The increased income from exports will lead to a growth of imports, especially those of consumer goods, as the living standard of Russian citizens rises. The forecasts produced by the Russian Government concerning the economic development of Russia up till 2030 also indicate a shift in exported goods from raw materials to processed products, which together with energy products will become the main export goods of Russia. As a consequence, Russia may need export routes through third countries, which can be seen as an opportunity for increased transit transports through the ports of Finland. The ports competing with the ports of Finland for Russian foreign trade traffic are the Russian Baltic Sea ports and the ports of the Baltic countries. The strongest competitors are the Baltic Sea ports handling containers. On the Russian Baltic Sea, these ports include Saint Petersburg, Kaliningrad and, in the near future, the ports of Ust-Luga and possibly Vyborg. There are plans to develop Ust-Luga and Vyborg as modern container ports, which would become serious competitors to the Finnish ports. Russia is aiming to redirect as large a share as possible of foreign trade traffic to its own ports. The ports of Russia and the infrastructure associated with them are under constant development. On the other hand, the logistic capacity of Russia is not able to satisfy the continually growing needs of the Russian foreign trade. The capacity problem is emphasized by a structural incompatibility between the exports and imports in the Russian foreign trade. Russian exports can only use a small part of the containers brought in with imports. Problems are also caused by the difficult ice conditions and narrow waterways leading to the ports. It is predicted that Finland will maintain its position as a transit route for the Russian foreign trade, at least in the near future. The Russian foreign trade is increasing, and Russia will not be able to develop its ports in proportion with the increasing foreign trade. With the development of port capacity, cargo flows through the ports of Russia will grow. Structural changes in transit traffic are already visible. Firms are more and more relocating their production to Russia, for example as regards the assembly of cars and warehousing services. Simultaneously, an increasing part of transit cargoes are sent directly to Russia without unloading and reloading in Finland. New product groups have nevertheless been transported through Finland (textile products and tools), replacing the lost cargos. The global recession that started in autumn 2008 has influenced the volume of Russian imports and, consequently, the transit volumes of Finland, but the recession is not expected to be of long duration, and will thus only have a short-term impact on transit volumes. The Finnish infrastructure and services offered by the logistic chain should also be ready to react to the changes in imported product groups as well as to the change in Russian export products in the future. If the development plans of the Russian economy are realized, export products will be more refined, and the share of energy and raw material products will decrease. The other notable factor to be taken into consideration is the extremely fast-changing business environment in Russia. Operators in the logistic chain should be flexible enough to adapt to all kinds of changes to capitalise on business opportunities offered by the Russian foreign trade for the companies and for the transit volumes of Finnish ports, also in the future.

Holocene Varved Lake Sediments as Records of Palaeoenvironmental Change and Geomagnetic Palaeosecular Variation in Eastern Finland

This dissertation discusses Holocene palaeoenvironmental and palaeomagnetic secular variation (PSV) records reconstructed from sediments preserved in Lake Lehmilampi (63º37´N, 29º06´E) and Lake Kortejärvi (63º37´N, 28º56´E) in eastern Finland. Several piston and freeze cores were obtained from both lakes for varve and magnetic analyses. Sediment samples were impregnated in low-viscosity epoxy and physical parameters of varves, including varve thickness and relative grey-scale values, were recorded using x-ray densitometry combined with semiautomatic digital image analysis. On average, varve records of Lehmilampi and Kortejärvi cover 5122 and 3902 years, respectively. Past solar activity, as estimated by residual ₁₄C data, compares favourably with varve thicknesses from Lehmilampi during the last 2000 years. This indicates the potential of clastic-organic varves to record sensitively climatic variations. Bulk magnetic parameters, including magnetic susceptibility together with natural, anhysteretic and isothermal remanent magnetizations, were measured to describe mineral magnetic properties and geomagnetic palaeosecular variation recorded in the sediments. Main stages in the development of the investigated lakes are reflected in the variations in the mineral magnetic records, sediment lithology and composition. Similar variations in magnetic parameters and sediment organic matter suggest contribution of bacterial magnetite in the magnetic assemblages of Lehmilampi. Inclination and relative declination records yielded largely consistent results, attesting to the great potential of these sediments to preserve directional palaeosecular variation in high resolution. The PSV data from Lehmilampi and Kortejärvi were stacked into North Karelian PSV stack, which may be used for dating homogenous lake sediments in the same regional context. Reconstructed millennial variations in relative palaeointensity results are approximately in agreement with those seen in the absolute palaeointensity data from Europe. Centennial variations in the relative palaeointensity, however, are influenced by environmental changes. Caution is recommended when using varved lake sediments in reconstructing relative palaeointensity.

Travels through Sweden, Finland, and Lapland, to the North Cape, in the years 1798 and 1799 : by Joseph Acerbi. In two volumes. Illustrated with seventeen elegant engravings. Vol. I[-II].

Vol. I: Portrait of Joseph Acerbi. Painted by P. Violet, engr. by P. W. Tomkins.

Vägvisare til och ifrån alla städer och namnkunniga orter, uti Svea- och Göta-Riken, samt Stor-Förstendömet Finland; jämte tvänne uti koppar stuckne väg-chartor, efter skedde vägmätningar uprättad : af Georg Biurman.

Digital reproduction, The National Library of Finland, Centre for Preservation and Digitisation, Mikkeli

Reise durch Schweden, Schwedisch-Lapland, Finland und Dänemark : von Matthaus Consett, esq. Aus dem Englischen übersetzt. Mit Kupfern.

Bound with: Reise durch Russland wie auch durch unterschiedliche europäische und assiatische Provinzen von 1770-1780 / Jacob Fries. [Leipzig], 1790.

Reizen door Zweeden en Finland, tot aan de uiterste grenzen van Lapland, in de jaaren 1798 en 1799 : door Joseph Acerbi. Uit het engelsch. ... Eerste deel[-vierde en laatste deel].

Digital reproduction, The National Library of Finland, Centre for Preservation and Digitisation, Mikkeli