37 resultados para External-beam Irradiation
Resumo:
The main objective of this thesis is to show that plate strips subjected to transverse line loads can be analysed by using the beam on elastic foundation (BEF) approach. It is shown that the elastic behaviour of both the centre line section of a semi infinite plate supported along two edges, and the free edge of a cantilever plate strip can be accurately predicted by calculations based on the two parameter BEF theory. The transverse bending stiffness of the plate strip forms the foundation. The foundation modulus is shown, mathematically and physically, to be the zero order term of the fourth order differential equation governing the behaviour of BEF, whereas the torsion rigidity of the plate acts like pre tension in the second order term. Direct equivalence is obtained for harmonic line loading by comparing the differential equations of Levy's method (a simply supported plate) with the BEF method. By equating the second and zero order terms of the semi infinite BEF model for each harmonic component, two parameters are obtained for a simply supported plate of width B: the characteristic length, 1/ λ, and the normalized sum, n, being the effect of axial loading and stiffening resulting from the torsion stiffness, nlin. This procedure gives the following result for the first mode when a uniaxial stress field was assumed (ν = 0): 1/λ = √2B/π and nlin = 1. For constant line loading, which is the superimposition of harmonic components, slightly differing foundation parameters are obtained when the maximum deflection and bending moment values of the theoretical plate, with v = 0, and BEF analysis solutions are equated: 1 /λ= 1.47B/π and nlin. = 0.59 for a simply supported plate; and 1/λ = 0.99B/π and nlin = 0.25 for a fixed plate. The BEF parameters of the plate strip with a free edge are determined based solely on finite element analysis (FEA) results: 1/λ = 1.29B/π and nlin. = 0.65, where B is the double width of the cantilever plate strip. The stress biaxial, v > 0, is shown not to affect the values of the BEF parameters significantly the result of the geometric nonlinearity caused by in plane, axial and biaxial loading is studied theoretically by comparing the differential equations of Levy's method with the BEF approach. The BEF model is generalised to take into account the elastic rotation stiffness of the longitudinal edges. Finally, formulae are presented that take into account the effect of Poisson's ratio, and geometric non linearity, on bending behaviour resulting from axial and transverse inplane loading. It is also shown that the BEF parameters of the semi infinite model are valid for linear elastic analysis of a plate strip of finite length. The BEF model was verified by applying it to the analysis of bending stresses caused by misalignments in a laboratory test panel. In summary, it can be concluded that the advantages of the BEF theory are that it is a simple tool, and that it is accurate enough for specific stress analysis of semi infinite and finite plate bending problems.
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The aim of this thesis was to find out how the carbon footprint calculations can be utilized in the company’s external environmental communication, what is the demand for carbon footprint from the market, and how the other actors in the forest industry have approached the issue. The aim was to recognize the best practises to communicate carbon footprints and to find possibilities to extend the UPM-Kymmene Wood Oy’s mill specific carbon footprints. This research included a literature review, an inquiry to the UPM-Kymmene Wood Oy’s sales offices, and Internet survey concerning the external environmental communication in the forest industry and three small case studies based on mill specific parameters. The inquiry to the sales offices showed that the carbon footprint is not yet a common demand from the customers in the wood product sector. In addition, the Internet survey showed that generally in the forest industry, not much has been done concerning carbon footprint communication so far. The biggest challenge in carbon footprint communication is the variation in the knowledge level of the receivers. In addition btob and btoc communication situations demand a different approach to the issue. Carbon profile brochures developed in the company can be seen as suitable for btob communication situations. Case studies have shown that the contribution of final product transport to the overall carbon footprint was significant. It was recommended to include post mill transport in the carbon footprint information supplied to the btob customers. When discussing environmental communication on a general level it can be stated that a good external environmental communication is based on facts, is open and proactive and takes into account the needs of the receiver. However, the openness and the quality of external environmental communication are essentially strategic decisions. The significance of internal communication as well as the knowhow in the communication and marketing networks play a major role in achieving success in external environmental communication. Carbon footprints are only one part of good balanced external environmental communication. One specific environmental feature like carbon footprint should not be over emphasized to the detriment of other important environmental aspects.
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In knowledge-intensive economy an effective knowledge transfer is a part of the firm’s strategy to achieve a competitive advantage in the market. Knowledge transfer related to a variety of mechanisms depends on the nature of knowledge and context. The topic is, however, very little empirical studied and there is a research gap in scientific literature. This study examined and analyzed external knowledge transfer mechanisms in service business and especially in the context of acquisitions. The aim was to find out what kind of mechanisms was used when the buyer began to transfer data e.g. their own agendas and practices to the purchased units. Another major research goal was to identify the critical factors which contributed to knowledge transfer through different mechanisms. The study was conducted as a multiple-case study in a consultative service business company, in its four business units acquired by acquisition, in various parts of the country. The empirical part of the study was carried out as focus group interviews in each unit, and the data were analyzed using qualitative methods. The main findings of this study were firstly the nine different knowledge transfer mechanisms in service business acquisition: acquisition management team as an initiator, unit manager as a translator, formal training, self-directed learning, rooming-in, IT systems implementation, customer relationship management, codified database and ecommunication. The used mechanisms brought up several aspects as giving the face to changing, security of receiving right knowledge and correctly interpreted we-ness atmosphere, and orientation to use more consultative touch with customers. The study pointed out seven critical factors contributed to different mechanisms: absorption, motivation, organizational learning, social interaction, trust, interpretation and time resource. The two last mentioned were new findings compared to previous studies. Each of the mechanisms and the related critical factors contributed in different ways to the activity in different units after the acquisition. The role of knowledge management strategy was the most significant managerial contribution of the study. Phenomenon is not recognized enough although it is strongly linked in knowledge based companies. The recognition would help to develop a better understanding of the business through acquisitions, especially in situations such as where two different knowledge strategies combines in new common company.
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Työssä tutkitaan kattilalaitosten vaativien, ulkoista kuormaa kantavien savukaasu- ja palamisilmakanavien rakennemitoitusta. Teoriaosuudessa esitetään vaativien kanavien mitoituksessa tarvittava levy- ja palkkilujuusoppi. Kantavien rakenteiden Eurokoodi-standardien soveltuvuutta kanavien mitoitukseen on tutkittu elementtimenetelmän avulla. Tutkittuja menetelmiä sovelletaan case-rakenteen mitoituksessa.
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Tässä diplomityössä tehtiin Olkiluodon ydinvoimalaitoksella sijaitsevan käytetyn ydinpolttoaineen allasvarastointiin perustuvan välivaraston todennäköisyysperustainen ulkoisten uhkien riskianalyysi. Todennäköisyysperustainen riskianalyysi (PRA) on yleisesti käytetty riskien tunnistus- ja lähestymistapa ydinvoimalaitoksella. Työn tarkoituksena oli laatia täysin uusi ulkoisten uhkien PRA-analyysi, koska Suomessa ei ole aiemmin tehty vastaavanlaisia tämän tutkimusalueen riskitarkasteluja. Riskitarkastelun motiivina ovat myös maailmalla tapahtuneiden luonnonkatastrofien vuoksi korostunut ulkoisten uhkien rooli käytetyn ydinpolttoaineen välivarastoinnin turvallisuudessa. PRA analyysin rakenne pohjautui tutkimuksen alussa luotuun metodologiaan. Analyysi perustuu mahdollisten ulkoisten uhkien tunnistamiseen pois lukien ihmisen aikaansaamat tahalliset vahingot. Tunnistettujen ulkoisten uhkien esiintymistaajuuksien ja vahingoittamispotentiaalin perusteella ulkoiset uhat joko karsittiin pois tutkimuksessa määriteltyjen karsintakriteerien avulla tai analysoitiin tarkemmin. Tutkimustulosten perusteella voitiin todeta, että tiedot hyvin harvoin tapahtuvista ulkoisista uhista ovat epätäydellisiä. Suurinta osaa näistä hyvin harvoin tapahtuvista ulkoisista uhista ei ole koskaan esiintynyt eikä todennäköisesti koskaan tule esiintymään Olkiluodon vaikutusalueella tai edes Suomessa. Esimerkiksi salaman iskujen ja öljyaltistuksen roolit ja vaikutukset erilaisten komponenttien käytettävyyteen ovat epävarmasti tunnettuja. Tutkimuksen tuloksia voidaan pitää kokonaisuudessaan merkittävinä, koska niiden perusteella voidaan osoittaa ne ulkoiset uhat, joiden vaikutuksia olisi syytä tutkia tarkemmin. Yksityiskohtaisempi tietoisuus hyvin harvoin esiintyvistä ulkoisista uhista tarkentaisi alkutapahtumataajuuksien estimaatteja.
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This dissertation explores the use of internal and external sources of knowledge in modern innovation processes. It builds on a framework that combines theories such as a behavioural theory of the firm, the evolutionary theory of economic change, and modern approaches to strategic management. It follows the recent increase in innovation research focusing on the firm-level examination of innovative activities instead of traditional industry-level determinants. The innovation process is seen as a problem- and slack- driven search process, which can take several directions in terms of organizational boundaries in the pursuit of new knowledge and other resources. It thus draws on recent models of technological change, according to which firms nowadays should build their innovative activities on both internal and external sources of innovation rather than relying solely on internal resources. Four different research questions are addressed, all of which are empirically investigated via a rich dataset covering Finnish innovators collected by Statistics Finland. Firstly, the study examines how the nature of problems shapes the direction of any search for new knowledge. In general it demonstrates that the nature of the problem does affect the direction of the search, although under resource constraints firms tend to use external rather than internal sources of knowledge. At the same time, it shows that those firms that are constrained in terms of finance seem to search both internally and externally. Secondly, the dissertation investigates the relationships between different kinds of internal and external sources of knowledge in an attempt to find out where firms should direct their search in order to exploit the potential of a distributed innovation process. The concept of complementarities is applied in this context. The third research question concerns how the use of external knowledge sources – openness to external knowledge – influences the financial performance of firms. Given the many advantages of openness presented in the current literature, the focus is on how it shapes profitability. The results reveal a curvilinear relationship between profitability and openness (taking an inverted U-shape), the implication being that it pays to be open up to a certain point, but being too open to external sources may be detrimental to financial performance. Finally, the dissertation addresses some challenges in CISbased innovation research that have received relatively little attention in prior studies. The general aim is to underline the fact that comprehensive understanding of the complex process of technological change requires the constant development of methodological approaches (in terms of data and measures, for example). All the empirical analyses included in the dissertation are based on the Finnish CIS (Finnish Innovation Survey 1998-2000).
Resumo:
Besides the sustaining of healthy and comfortable indoor climate, the air conditioning system should also achieve for energy efficiency. The target indoor climate can be ob-tained with different systems; this study focuses on comparing the energy efficiency of different air conditioning room unit systems in different climates. The calculations are made with dynamic energy simulation software IDA ICE by comparing the indoor cli-mate and energy consumption of an office building with different systems in different climates. The aim of the study is to compare the energy efficiency of chilled beam systems to other common systems: variable air volume, fan coil and radiant ceiling systems. Besides the annual energy consumption also the sustainability of target indoor climate is compared between the simulations. Another aim is to provide conclusions to be used in the product development of the chilled beam systems’ energy efficiency. The adaptable chilled beam system and the radiant ceiling system prove to be energy efficient independent of the climate. The challenge of reliable comparison is that other systems are not able to reach the target indoor climate as well as the others. The complex calculation environment of the simulation software, made assumptions and excluding of the financial aspects complicate comparing the big picture. The results show that the development of the chilled beam systems should concentrate on energy efficient night heating, flexible demand based ventilation and capacity control and possibilities on integrating the best practices with other systems.
Resumo:
Globalization, pervasiveness of technology and ICT, and the buildup of information societies and policies have lead to a growing abundance of knowledge and highly educated labour supply that is distributed widely. These changes have shifted the foundation of competitiveness to valuable knowledge resources which are now distributed widely across the globe, across actors in the value chain and across educated individuals in multiple organizations. Against this backdrop, the paradigm of open innovation (OI) has emerged as a new response to managing the increased amount of boundary-spanning knowledge flows in and out of the innovation process. The outbound mode of open innovation, that is to say the external exploitation of knowledge assets outside of the firm’s own products and services, has been the less-researched aspect of the concept and so far typically seen as concerning the outlicensing of unused technological assets to generate additional revenue. Given that open innovation is essentially a framework for the holistic structuring and management of crossboundary knowledge flows to improve a firm’s innovative performance, a close integration to corporate strategy seems imperative in order to fully benefit from it. Integrating open innovation to strategy leads to elevating its role from a fringe activity to a central innovation management issue that needs to be systematically managed. Building a structure that allows effective management necessitates linking open innovation activities to each phase of the innovation process. Previously, the connection between outbound OI and the earlier stages of innovation has not been studied. The thesis finds that connecting outbound OI to the entire innovation process of the firm, including the fuzzy front end of innovation, is critical for attaining strategic objectives and to the successful implementation and management of the activity. The practical purpose for the research is to enable companies to fully utilize their potential for outbound open innovation and to be able to implement and manage it from a strategic standpoint.
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Rajallistamisen kulttuuri(t): Eurooppalaistuminen ja kulttuurinen toimijuus Euroopan unionin ulkorajalla Euroopan integraation ja Euroopan unionin laajentumisen myötä EU:n sisärajat ovat avautuneet kun taas sen ulkorajoilla lisääntyvää rajan ylitysten valvontaa on pyritty kompensoimaan yhteistyön merkitystä ja verkostoitumista painottamalla. Tämä tutkimus pyrkii ymmärtämään EU:n ulkorajan muutosten merkitystä paikalliselle hyvinvoinnille sekä laajemmin ylirajaisuuden merkitystä identiteettien rakentamiselle raja-alueilla. EU:n ulkorajalla Puolassa ja Suomessa toteutettavat rajat ylittävät, kulttuuriin ja kulttuuriperintöön liittyvät, projektit kertovat eurooppalaistumisesta ja sen vaikutuksista kulttuurisen horisontin muutokselle. Voidaan nähdä miten Eurooppa kulttuurisena konstruktiona tulee paikallisesti merkittäväksi tavoilla jotka kertovat myös paikallisten toimijoiden mahdollisuuksista osallistua EU-rajan muutoksia ja paikallisuutta määritteleviin prosesseihin. Tällöin erityisesti raja-alueiden materiaalisen perinnön, ja sen mahdollistamien rajaan liittyvien neuvottelujen, voidaan nähdä kertovat Eurooppalaistumisesta myös ns. alhaaltapäin muotoutuvana prosessina. Artikkeliväitöskirjan taustalla on Puolan ja Suomen toisen maailmansodan seurauksena luovuttamien raja-alueiden (Kresy ja Karjala) asema nykyisellä Euroopan unionin ulkorajalla. Tutkimusidea perustuu tutkijan omiin kokemuksiin projekteista Puolan ja Ukrainan raja-alueella vuonna 2003, ennen Puolan liittymistä EU:hun vuonna 2004. Tutkimusaineisto on peräisin vuosien 2005-2009 aikana tehdyistä ns. monipaikkaisista (multi-sited) kenttätöistä EU:n ulkorajalla, pääosin Puolassa ja Suomessa, joissa kohteena olivat kulttuuria ja kulttuuriperintöä hyödyntävät, pääosin EU-rahoitetut, rajat ylittävät projektit. Materiaalit koostuvat 34 projektitoimijan haastatteluista, projektien materiaaleista, kenttätöiden havainnoista, paikallisten sanomalehtien artikkeleista sekä eri tasoilla (EU, kansallinen, alueellinen) tuotetuista ohjelmadokumenteista. Huomio kiinnittyy projektitoimijoiden tapoihin tehdä rajanylityksiä, sekä heidän tapaansa kokea ja hyödyntää raja-alueiden kulttuuriperintöä sekä ymmärtää niiden nykyistä kulttuurista moninaisuutta. Tällöin havaitaan miten erilaiset eurooppalaiset ideat, representaatiot ja käytänteet tulevat osaksi erilaisia translokaaleja, rajat ylittäviä ja paikallis-eurooppalaisia, suhteita. Vertailun kohteeksi eivät tällöin asetu projektit, toimijat tai raja-alueet sinänsä, vaan näihin suhteisiin liittyvä kulttuurinen toimijuus. Keskeinen käsite tutkimuksessa on ’rajallistaminen’, eli sen havaitseminen, miten jokainen rajan ylitys tarkoittaa myös neuvottelua rajasta. Rajan ylitys voi siis tarkoittaa myös sen vahvistamista. Myös itse raja voi asettua toiminnan kohteeksi, jolloin nousee esiin se, miten rajat ylittäviä ”kulttuureja” käytetään ja mitkä ovat niiden rajaan liittyvät paikalliset merkitykset. Kysymys on siitä kuka, ja kenelle, rajan merkityksiä neuvottelee? Projektitoimijoiden voidaan nähdä neuvottelevan näitä erilaisia ”kulttuureja” jotka tuottavat rajaa neuvottelevia suhteita, kuten esimerkiksi yhteistyön verkostojen tapaa ohittaa rajan paikallinen merkitys. Tämä rajallistaminen voi kuitenkin tarkoittaa myös paikallisten kulttuuristen identifikaatioiden huomioimista. Tällöin kyse on myös sen luovuuden havaitsemisesta, jota yksilöillä on kun he neuvottelevat näitä erilaisia rajallistamisen kulttuureja. Erityisesti toisen maailmansodan seurauksena valtiorajoista tuli vahvasti kansallisia kulttuureja erottavia, mutta nyt kulttuurisista rajoista neuvotellaan ja rajojen yli tapahtuva vuorovaikutus, sekä paikallisen ja Eurooppalaisen tason väliset suhteet, ja niiden moniäänisyys, nousevat tutkimuksen keskiöön. Tutkimuksen yhteenvedon kannalta keskeinen on kysymys raja/alueen kestävyydestä. Tyypillisesti verkostoitumista painottavan rajat ylittävän yhteistyön suhde paikalliseen yhteisöön voi jäädä häilyväksi. Tavoite paikallisen kulttuuriperinnön suojeluun ei itsessään vielä kerro sen merkityksestä paikalliselle hyvinvoinnille. Arvioinnin kannalta on hyödyllistä nähdä miten myös materiaalisella perinnöllä on toimijuutta osana paikallisuutta muokkaavia suhteita. Paikallisten asukkaiden kokemus rajasta voi edelleen olla että se ei ole muuttunut Neuvostoliiton ajoista, toisaalta EU:nkin voidaan toivoa määrittelemään rajansa vielä tarkemmin, jotta sen kansallinen luonne muuttuisi. Tutkimus nostaa esiin miten eurooppalaiset yhteistyötä ja kulttuurista moninaisuutta korostavat ideat ja käytänteet vaikuttavat erityisesti puolalaisten toimijoiden mahdollisuuksiin määritellä EU-rajaan liittyviä prosesseja osana paikallisia kulttuuriperinnön määrittelyjä. Paikallisten rajaan liittyvien kulttuuristen identifikaatioiden liittäminen osaksi projekteja ei kuitenkaan ole helppoa. Toisaalta rajan merkitys on sisäistetty osana arkea, toisaalta taas rajaan liittyvät suuret kertomukset kansallisena ja EU-rajana voivat olla etäännyttäviä tekijöitä. EU-raja, projektit ja monikulttuurisen perinnön autenttisuus ovat kuitenkin raja-alueen toimijoille ja yhteisöille mahdollisuus osallistua rajallistamiseen. Toiminnan kestävyyden kannalta kyse on pitkälti siitä avaako rajallistaminen paikallisen perinnön merkityksiä osana paikallis-eurooppalaisia suhteita.
Resumo:
The capacity of beams is a very important factor in the study of durability of structures and structural members. The capacity of a high-strength steel I-beam made of S960 QC was investigated in this study. The investigation included assessment of the service limits and ultimate limits of the steel beam. The thesis was done according to European standards for steel structures, Eurocode 3. An analytical method was used to determine the throat thickness, deformation, elastic and plastic moment capacities as well as the fatigue life of the beam. The results of the analytical method were compared with those obtained by Finite Element Analysis (FEA). Elastic moment capacity obtained by the analytical method was 172 kNm. FEA and the analytical method predicted the maximum lateral-torsional buckling (LTB) capacity in the range of 90-93 kNm and the probability of failure as a result of LTB is estimated to be 50%. The lateral buckling capacity meant that the I-beam can carry a safe load of 300 kN instead of the initial load of 600 kN. The beam is liable to fail shortly after exceeding the elastic moment capacity. Based on results in of the different approaches, it was noted that FEA predicted higher deformation values on the load-deformation curve than the analytical results. However, both FEA and the analytical methods predicted identical results for nominal stress range and moment capacities. Fatigue life was estimated to be in the range of 53000-64000 cycles for bending stress range using crack propagation equation and strength-life approach. As Eurocode 3 is limited to steel grades up to S690, results for S960 must be verified with experimental data and appropriate design rules.
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The interferometer for low resolution portable Fourier Transform middle infrared spectrometer was developed and studied experimentally. The final aim was a concept for a commercial prototype. Because of the portability, the interferometer should be compact sized and insensitive to the external temperature variations and mechanical vibrations. To minimise the size and manufacturing costs, Michelson interferometer based on plane mirrors and porch swing bearing was selected and no dynamic alignment system was applied. The driving motor was a linear voice coil actuator to avoid mechanical contact of the moving parts. The driving capability for low mirror driving velocities required by the photoacoustic detectors was studied. In total, four versions of such an interferometer were built and experimentally studied. The thermal stability during the external temperature variations and the alignment stability over the mirror travel were measured using the modulation depth of the wide diameter laser beam. Method for estimating the mirror tilt angle from the modulation depth was developed to take account the effect from the non-uniform intensity distribution of the laser beam. The spectrometer stability was finally studied also using the infrared radiation. The latest interferometer was assembled for the middle infrared spectrometer with spectral range from 750 cm−1 to 4500 cm−1. The interferometer size was (197 × 95 × 79) mm3 with the beam diameter of 25 mm. The alignment stability as the change of the tilt angle over the mirror travel of 3 mm was 5 μrad, which decreases the modulation depth only about 0.7 percent in infrared at 3000 cm−1. During the temperature raise, the modulation depth at 3000 cm−1 changed about 1 . . . 2 percentage units per Celsius over short term and even less than 0.2 percentage units per Celsius over the total temperature raise of 30 °C. The unapodised spectral resolution was 4 cm−1 limited by the aperture size. The best achieved signal to noise ratio was about 38 000:1 with commercially available DLaTGS detector. Although the vibration sensitivity requires still improving, the interferometer performed, as a whole, very well and could be further developed to conform all the requirements of the portable and stable spectrometer.
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Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014
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The growing pharmaceutical interest, among others, in the polymorphic composition of the emerging solid end-products from production processes has been traced to the need for attainment of high product purity. This is more so as the presence of different polymorphs may constitute physical impurity of the product. Hence, the need for optimization of the yield of desired product component(s) through controlled crystallization kinetics for instance. This study was carried out to investigate the impact of pulsed electric field (PEF) irradiation on the crystal morphology of glycine obtained by cooling crystallization (without seeding) from commercial glycine sample in distilled deionized water solution. In doing so, three different pulse frequencies (294, 950 and 145 Hz) and a case without PEF were studied at three cooling rates (5, 10 and 20 ºC/h). The crystal products obtained were analyzed for polymorphic composition by powder x-ray diffraction (PXRD) and Fourier transform infrared (FTIR) spectroscopy while the particles characterization was done on Morphologi G3. The results obtained from this study showed that pulsed electric field irradiation had significant impact on metastability of the aqueous solution as well as on the polymorphic composition of the end product. With increasing PEF frequency applied, nucleation started earlier and the γ-glycine polymorph content of the product crystals increased. These were found to have been aided by cooling rate, as the most significant effect was observed at 5 ºC/h. It was also discovered that PEF application had no measurable impact on the pH of the aqueous solution as well as the size distribution of the particles. Cooling on the contrary was believed to be responsible for the broadening of the particle size distribution with a downward shift of the lower limit of the raw material from about 100 μm to between 10 and 50 μm.