974 resultados para Merits and Defects of Technology


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Point defects of opposite signs can alternately nucleate on the -1/2 disclination line that forms near the free surface of a confined nematic liquid crystal. We show the existence of metastable configurations consisting of periodic repetitions of such defects. These configurations are characterized by a minimal interdefect spacing that is seen to depend on sample thickness and on an applied electric field. The time evolution of the defect distribution suggests that the defects attract at small distances and repel at large distances.

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Wiss, Janney, Elstner Associates, Inc. (WJE) evaluated potential nondestructive evaluation (NDE) methodologies that may be effective in 1) identifying internal defects within slip formed concrete barriers and 2) assessing the corrosion condition of barrier dowel bars. The evaluation was requested by the Bridge Maintenance and Inspection Unit of the Iowa Department of Transportation (IaDOT) and the Bureau of Bridges and Structures of the Illinois Department of Transportation (IDOT). The need arose due to instances in each Department’s existing inventory of bridge barriers where internal voids and other defects associated with slip forming construction methods were attributed to poor barrier performance after completion of construction and where, in other barrier walls, unintentional exposure of the dowel bars revealed extensive corrosion-related section loss at previously uninspectable locations, reducing the capacity of the barriers to resist traffic impact loads. WJE trial tested potential NDE techniques on laboratory mock-up samples built with known defects, trial sections of cast-in-place barriers at in-service bridges in Iowa, and slip formed and cast-in-place barrier walls at in-service bridges in Illinois. The work included review of available studies performed by others, field trial testing to assess candidate test methods, verification of the test methods in identifying internal anomalies and dowel bar corrosion, and preparation of this report and nondestructive evaluation guidelines.

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The antibody display technology (ADT) such as phage display (PD) has substantially improved the production of monoclonal antibodies (mAbs) and Ab fragments through bypassing several limitations associated with the traditional approach of hybridoma technology. In the current study, we capitalized on the PD technology to produce high affinity single chain variable fragment (scFv) against tumor necrosis factor-alpha (TNF- α), which is a potent pro-inflammatory cytokine and plays important role in various inflammatory diseases and malignancies. To pursue production of scFv antibody fragments against human TNF- α, we performed five rounds of biopanning using stepwise decreased amount of TNF-α (1 to 0.1 μ g), a semi-synthetic phage antibody library (Tomlinson I + J) and TG1 cells. Antibody clones were isolated and selected through enzyme-linked immunosorbent assay (ELISA) screening. The selected scFv antibody fragments were further characterized by means of ELISA, PCR, restriction fragment length polymorphism (RFLP) and Western blot analyses as well as fluorescence microscopy and flow cytometry. Based upon binding affinity to TNF-α , 15 clones were selected out of 50 positive clones enriched from PD in vitro selection. The selected scFvs displayed high specificity and binding affinity with Kd values at nm range to human TNF-α . The immunofluorescence analysis revealed significant binding of the selected scFv antibody fragments to the Raji B lymphoblasts. The effectiveness of the selected scFv fragments was further validated by flow cytometry analysis in the lipopolysaccharide (LPS) treated mouse fibroblast L929 cells. Based upon these findings, we propose the selected fully human anti-TNF-α scFv antibody fragments as potential immunotherapy agents that may be translated into preclinical/clinical applications.

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Tämän Pro gradu-tutkielman tavoitteena olirakentaa esiymmärrys sosiaalisen pääoman roolista ja mittaamisesta uuden teknologian start-up yrityksissä. Pääasiallisena tarkoituksena tässä tutkimuksessa olilöytää sosiaalisen pääoman ja start-up yrityksen tuloksellisuuden välille yhdistävä tekijä. Tutkimuksen empiirinen aineisto kerättiin pääasiallisesti kuuden OKO Venture Capitalin sijoitusportfolioon sisältyvien case-yritysten kvalitatiivisten teemahaastatteluiden sekä kvantitatiivisten kyselylomakkeiden avulla. Kvalitatiivisten haastatteluiden tulosten perusteella sosiaalisen pääoman ja tuloksellisuuden välille löytyi yhdistävä tekijä, jota käytettiin myöhemmin hyväksi kvantitatiivisessa kyselylomakkeessa. Tämän tutkielman tulokset osoittivat, että startegisen päätöksenteon kautta sosiaalinen pääoma vaikuttaa osittain start-up yritysten tuloksellisuuteen. Manageriaalisesti tärkempi löydös tässä tutkimuksessa oli kuitenkin se, että sosiaalista pääomaa voidaan käyttää hyväksi ennustettaessa uuden teknologian start-up yritysten tulevaisuuden kassavirtoja.

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Process development will be largely driven by the main equipment suppliers. The reason for this development is their ambition to supply complete plants or process systems instead of single pieces of equipment. The pulp and paper companies' interest lies in product development, as their main goal is to create winning brands and effective brand management. Design engineering companies will find their niche in detail engineering based on approved process solutions. Their development work will focus on increasing the efficiency of engineering work. Process design is a content-producing profession, which requires certain special characteristics: creativity, carefulness, the ability to work as a member of a design team according to time schedules and fluency in oral as well as written presentation. In the future, process engineers will increasingly need knowledge of chemistry as well as information and automation technology. Process engineering tools are developing rapidly. At the moment, these tools are good enough for static sizing and balancing, but dynamic simulation tools are not yet good enough for the complicated chemical reactions of pulp and paper chemistry. Dynamic simulation and virtual mill models are used as tools for training the operators. Computational fluid dynamics will certainlygain ground in process design.

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There is a broad consensus among economists that technologicalchange has been a major contributor to the productivity growth and, hence, to the growth of the material welfare in western industrialized countries at least over the last century. Paradoxically, this issue has not been the focal point of theoretical economics. At the same time, we have witnessed the rise of the importance of technological issues at the strategic management level of business firms. Interestingly, the research has not accurately responded to this challenge either. The tension between the overwhelming empirical evidence of the importance of technology and its relative omission in the research offers a challenging target for a methodological endeavor. This study deals with the question of how different theories cope with technology and explain technological change. The focusis at the firm level and the analysis concentrates on metatheoretical issues, except for the last two chapters, which examine the problems of strategic management of technology. Here the aim is to build a new evolutionary-based theoreticalframework to analyze innovation processes at the firm level. The study consistsof ten chapters. Chapter 1 poses the research problem and contrasts the two basic approaches, neoclassical and evolutionary, to be analyzed. Chapter 2 introduces the methodological framework which is based on the methodology of isolation. Methodological and ontoogical commitments of the rival approaches are revealed and basic questions concerning their ways of theorizing are elaborated. Chapters 3-6 deal with the so-called substantive isolative criteria. The aim is to examine how different approaches cope with such critical issues as inherent uncertainty and complexity of innovative activities (cognitive isolations, chapter 3), theboundedness of rationality of innovating agents (behavioral isolations, chapter4), the multidimensional nature of technology (chapter 5), and governance costsrelated to technology (chapter 6). Chapters 7 and 8 put all these things together and look at the explanatory structures used by the neoclassical and evolutionary approaches in the light of substantive isolations. The last two cpahters of the study utilize the methodological framework and tools to appraise different economics-based candidates in the context of strategic management of technology. The aim is to analyze how different approaches answer the fundamental question: How can firms gain competitive advantages through innovations and how can the rents appropriated from successful innovations be sustained? The last chapter introduces a new evolutionary-based technology management framework. Also the largely omitted issues of entrepreneurship are examined.

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The future of high technology welded constructions will be characterised by higher strength materials and improved weld quality with respect to fatigue resistance. The expected implementation of high quality high strength steel welds will require that more attention be given to the issues of crack initiation and mechanical mismatching. Experiments and finite element analyses were performed within the framework of continuum damage mechanics to investigate the effect of mismatching of welded joints on void nucleation and coalescence during monotonic loading. It was found that the damage of undermatched joints mainly occurred in the sandwich layer and the damageresistance of the joints decreases with the decrease of the sandwich layer width. The damage of over-matched joints mainly occurred in the base metal adjacent to the sandwich layer and the damage resistance of the joints increases with thedecrease of the sandwich layer width. The mechanisms of the initiation of the micro voids/cracks were found to be cracking of the inclusions or the embrittled second phase, and the debonding of the inclusions from the matrix. Experimental fatigue crack growth rate testing showed that the fatigue life of under-matched central crack panel specimens is longer than that of over-matched and even-matched specimens. Further investigation by the elastic-plastic finite element analysis indicated that fatigue crack closure, which originated from the inhomogeneousyielding adjacent to the crack tip, played an important role in the fatigue crack propagation. The applicability of the J integral concept to the mismatched specimens with crack extension under cyclic loading was assessed. The concept of fatigue class used by the International Institute of Welding was introduced in the parametric numerical analysis of several welded joints. The effect of weld geometry and load condition on fatigue strength of ferrite-pearlite steel joints was systematically evaluated based on linear elastic fracture mechanics. Joint types included lap joints, angle joints and butt joints. Various combinations of the tensile and bending loads were considered during the evaluation with the emphasis focused on the existence of both root and toe cracks. For a lap joint with asmall lack-of-penetration, a reasonably large weld leg and smaller flank angle were recommended for engineering practice in order to achieve higher fatigue strength. It was found that the fatigue strength of the angle joint depended strongly on the location and orientation of the preexisting crack-like welding defects, even if the joint was welded with full penetration. It is commonly believed that the double sided butt welds can have significantly higher fatigue strength than that of a single sided welds, but fatigue crack initiation and propagation can originate from the weld root if the welding procedure results in a partial penetration. It is clearly shown that the fatigue strength of the butt joint could be improved remarkably by ensuring full penetration. Nevertheless, increasing the fatigue strength of a butt joint by increasing the size of the weld is an uneconomical alternative.

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Tutkielman tavoitteena on tutkia, mikä olisi parhaiten case-yritykselle sopiva menetelmä tulla tekemään kauppaa ulkomaan markkinoille. Kaikki yleiset kansainvälisille markkinoilletulomenetelmät esitetään ja niiden edut ja haitat tuodaan esille. Selvittäessä tehtävänantajayrityksen resurssit, odotukset ja vaatimukset todetaan, että yhteistyössä tehtävä markkinoilletulo on pätevin vaihtoehto. Tämän jälkeen valitaan parhaiten tarkoitukseen sopiva yritys ennalta valitusta yritysvaihtoehtojen ryhmästä ja testataan tämän yrityksen yhteistyösopivuus case-yrityksen kanssa. Yritysten välinen yhteistyösopivuus arvioidaan analysoimalla yritykset haastattelujen avulla ja tutkielmassa esitettyjen teorioiden avulla. Sopivuus todetaan hyväksi, kattaen 71 prosenttia analysoiduista kohdista. Kaksikymmentäyhdeksän prosenttia kohdista todetaan kohdiksi, joissa yritysten välinen yhteisymmärrys ei ole toimeksiantajayrityksen minimivaatimukset täyttävää. Näitä kohtia tullaan käyttämään suunnittelun pohjana kun suunnitellaan jatkoneuvotteluja yhteistyön käynnistämiseksi.

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In this thesis theoretical and technological aspects of fiber Bragg gratings (FBG) are considered. The fabrication of uniform and chirped fiber Bragg gratings using phase mask technique has been exploited throughout this study. Different requires of FBG inscription were considered and implemented experimentally to find economical and effective procedure. The hydrogen loading was used as a method for enhancement the photosensitivity of the fiber. The minimum loading time for uniform and chirped fiber Bragg gratings was determined as 3 days and 7 days at T = 50°C and hydrogen pressure 140 bar, respectively. The post-inscription annealing was considered to avoid excess losses induced by the hydrogen. The wavelength evolution during annealing was measured. The strain and temperature sensor application of FBG was considered. The wavelength shifts caused by tension and temperature were studied for both uniform and chirp fiber Bragg gratings.

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Tampere University of Technology is undergoing a degree reform that started in 2013. One of the major changes in the reform was the integration of compulsory Finnish, Swedish and English language courses to substance courses at the bachelor level. The integration of content and language courses aims at higher quality language learning, more fluency in studies, and increased motivation toward language studies. In addition, integration is an opportunity to optimize the use of resources and to offer courses that are more tailored to the students' field of study and to the skills needed in working life. The reform also aims to increase and develop co-operation between different departments at the university and to develop scientific follow up. This paper gives an overview of the integration process conducted at TUT and gives examples of adjunct CLIL implementations in three different languages.

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The multidimensional process of physical, psychological, and social change produced by population ageing affects not only the quality of life of elderly people but also of our societies. Some dimensions of population ageing grow and expand over time (e.g. knowledge of the world events, or experience in particular situations), while others decline (e.g. reaction time, physical and psychological strength, or other functional abilities like reduced speed and tiredness). Information and Communication Technologies (ICTs) can help elderly to overcome possible limitations due to ageing. As a particular case, biometrics can allow the development of new algorithms for early detection of cognitive impairments, by processing continuous speech, handwriting or other challenged abilities. Among all possibilities, digital applications (Apps) for mobile phones or tablets can allow the dissemination of such tools. In this article, after presenting and discussing the process of population ageing and its social implications, we explore how ICTs through different Apps can lead to new solutions for facing this major demographic challenge.

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The aim of the paper is to investigate the role played by differences in Institutional Quality on the process of technology catch-up across countries. Empirical evidence shows how countries endowed with better institutions are those experiencing higher TFP growth rates, faster rates of technology adoption and hence being those more rapidly closing the gap with the frontier. Conversely, countries lacking some minimum institutional level are shown to diverge in the long run and not to catch-up. Some institutions, however, play an ambiguous role in the creation and adoption of technology. We find that the tightening of Intellectual Property Rights reduces the ability of followers to freely imitate technology slowing down their catchup rate. This negative effect is stronger the farther the countriesare found from the frontier. Other institutional categories such as openness to trade, instead, benefit both leaders and followers.

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In many industrial applications, accurate and fast surface reconstruction is essential for quality control. Variation in surface finishing parameters, such as surface roughness, can reflect defects in a manufacturing process, non-optimal product operational efficiency, and reduced life expectancy of the product. This thesis considers reconstruction and analysis of high-frequency variation, that is roughness, on planar surfaces. Standard roughness measures in industry are calculated from surface topography. A fast and non-contact method to obtain surface topography is to apply photometric stereo in the estimation of surface gradients and to reconstruct the surface by integrating the gradient fields. Alternatively, visual methods, such as statistical measures, fractal dimension and distance transforms, can be used to characterize surface roughness directly from gray-scale images. In this thesis, the accuracy of distance transforms, statistical measures, and fractal dimension are evaluated in the estimation of surface roughness from gray-scale images and topographies. The results are contrasted to standard industry roughness measures. In distance transforms, the key idea is that distance values calculated along a highly varying surface are greater than distances calculated along a smoother surface. Statistical measures and fractal dimension are common surface roughness measures. In the experiments, skewness and variance of brightness distribution, fractal dimension, and distance transforms exhibited strong linear correlations to standard industry roughness measures. One of the key strengths of photometric stereo method is the acquisition of higher frequency variation of surfaces. In this thesis, the reconstruction of planar high-frequency varying surfaces is studied in the presence of imaging noise and blur. Two Wiener filterbased methods are proposed of which one is optimal in the sense of surface power spectral density given the spectral properties of the imaging noise and blur. Experiments show that the proposed methods preserve the inherent high-frequency variation in the reconstructed surfaces, whereas traditional reconstruction methods typically handle incorrect measurements by smoothing, which dampens the high-frequency variation.

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Hoitajien informaatioteknologian hyväksyntä ja käyttö psykiatrisissa sairaaloissa Informaatioteknologian (IT) käyttö ei ole ollut kovin merkittävässä roolissa psykiatrisessa hoitotyössä, vaikka IT sovellusten on todettu vaikuttaneen radikaalisti terveydenhuollon palveluihin ja hoitohenkilökunnan työprosesseihin viime vuosina. Tämän tutkimuksen tavoitteena on kuvata psykiatrisessa hoitotyössä toimivan hoitohenkilökunnan informaatioteknologian hyväksyntää ja käyttöä ja luoda suositus, jonka avulla on mahdollista tukea näitä asioita psykiatrisissa sairaaloissa. Tutkimus koostuu viidestä osatutkimuksesta, joissa on hyödynnetty sekä tilastollisia että laadullisia tutkimusmetodeja. Tutkimusaineistot on kerätty yhdeksän akuuttipsykiatrian osaston hoitohenkilökunnan keskuudessa vuosien 2003-2006 aikana. Technology Acceptance Model (TAM) –teoriaa on hyödynnetty jäsentämään tutkimusprosessia sekä syventämään ymmärrystä saaduista tutkimustuloksista. Tutkimus osoitti kahdeksan keskeistä tekijää, jotka saattavat tukea psykiatrisessa sairaalassa toimivien hoitajien tietoteknologiasovellusten hyväksyntää ja hyödyntämistä, kun nämä tekijät otetaan huomioon uusia sovelluksia käyttöönotettaessa. Tekijät jakautuivat kahteen ryhmään; ulkoiset tekijät (resurssien suuntaaminen, yhteistyö, tietokonetaidot, IT koulutus, sovelluksen käyttöön liittyvä harjoittelu, potilas-hoitaja suhde), sekä käytön helppous ja sovelluksen käytettävyys (käytön ohjeistus, käytettävyyden varmistaminen). TAM teoria todettiin käyttökelpoiseksi tulosten tulkinnassa. Kehitetty suositus sisältää ne toimenpiteet, joiden avulla on mahdollista tukea sekä organisaation johdon että hoitohenkilökunnan sitoutumista ja tätä kautta varmistaa uuden sovelluksen hyväksyntä ja käyttö hoitotyössä. Suositusta on mahdollista hyödyntää käytännössä kun uusia tietojärjestelmiä implementoidaan käyttöön psykiatrisissa sairaaloissa.

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Education in Finland plays a significant role. International students are becoming an essential part of Finnish Educational system. The study was meant to examine their expectations and experiences in a Finnish University. As a case, Lappeenranta University of Technology (LUT) was chosen and, in particular, Information Technology (IT) Department. The main objectives of the study were to examine students’ satisfaction of their study experiences, their evaluation of the teaching quality of courses and last but not least the cultural impact on those. Data for the study were mainly collected with the help of three Internet surveys from a sample of 50 students – currently studying at LUT or already graduated. Response rate from questionnaire to questionnaire varied, however, still close to average and was considered as good and relevant enough. The study was initially meant as qualitative, however, a number of quantitative data analysis methods were used as well. Most of students’ expectations appear to become true, majority of students are satisfied with their experiences. Results show that teaching quality in LUT is evaluated as ‘good’. Nevertheless, students prefer particular courses to the other ones. In conclusion, it can be said that culture does affect students’ expectations, experiences, perception of the world, however, cultural differences do not cause any serious problems.