10 research outputs found

    Free-Motion Beam Propagation Factor Measurement by Means of a Liquid Crystal Spatial Light Modulator

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    In contrast to the mechanical scanning procedure described in the standard ISO/DIS 11146, the use of electronically tunable focal length lenses has proved its capability for the measurement of the laser beam propagation factor ( ) without moving components. Here, we demonstrate a novel experimental implementation where we use a low-cost programmable liquid crystal spatial light modulator (SLM) for sequentially codifying a set of lenses with different focal lengths. The use of this kind of modulators introduces some beneïŹts such as the possibility for high numerical aperture or local beam control of the phase of the lenses which allows for minimizing systematic errors originated by lens aberrations. The beamwidth, according to the second-order moment of the irradiance, is determined for each focal length by using a digital sensor at a ïŹxed position with respect to the spatial light modulator. After ïŹtting the measured data to the theoretical focusing behavior of a real laser beam, the beam propagation factor is obtained. We successfully validated the results in the laboratory where a full digital control of the measurement procedure without mechanical scanning was demonstrated

    Dispersion management in two-photon microscopy by using diffractive optical elements

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    We demonstrate efficient generation of wide-field fluorescence signals in two-photon microscopy exploiting diffractive optical elements and short pulses by using a dispersion-compensated beam delivery optics module. Computer-generated holograms are codified onto a phase-only spatial light modulator, which allows for arbitrary single-shot patterning of the sample. Spatiotemporal shaping of the pulse is mandatory to overcome spatial chirp and pulse-front tilt effects that spread both in space and time the irradiance patterns, thus limiting not only the spatial resolution but also the signal-to-noise ratio in two-photon microscopy. By using a multipass amplifier delivering 30 fs, 0.8 mJ pulses at 1 kHz repetition rate, we experimentally demonstrated arbitrary single-shot fluorescence irradiance patterns in Rhodamine B

    Multibeam second-harmonic generation by spatiotemporal shaping of femtosecond pulses

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    We present a technique for efficient generation of the second-harmonic signal at several points of a nonlinear crystal simultaneously. Multispot operation is performed by using a diffractive optical element that splits the near-infrared light of a mode-locked Ti:sapphire laser into an arbitrary array of beams that are transformed into an array of foci at the nonlinear crystal. We show that, for pulse temporal durations under 100 fs, spatiotemporal shaping of the pulse is mandatory to overcome chromatic dispersion effects that spread both in space and time the foci showing a reduced peak intensity that prevents nonlinear phenomena. We experimentally demonstrate arbitrary irradiance patterns for the second-harmonic signal consisting of more than 100 spots with a multipass amplifier delivering 28 fs, 0.8 mJ pulses at 1 kHz repetition rate.This work was supported by the Spanish Ministerio de Ciencia e InnovaciĂłn (MICINN) and FEDER through the projects FIS2010-15746, FIS2009-09522, and SAUUL (CSD2007-00013) and the FundaciĂł Caixa CastellĂł (P1- 1B2010-26)

    Competitiveness of the Estonian dairy sector, 1994–2014

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    Historically, the dairy sector has been one of the most important and competitive branches of the Estonian agriculture and food industry. Since the beginning of the transitional period 25 years ago, Estonian society and its economy have gone through significant institutional, political and societal changes, which have also affected the dairy sector. This paper provides a review of the competitiveness of the Estonian dairy sector. The competitiveness of dairy farms, the dairy processing industry and dairy exports are discussed from several perspectives applied in the studies of competitiveness. Also, the context of the transition to a market economy and institutional, policy and market changes are considered. In the past 20 years, the Estonian dairy sector has maintained its competitiveness in export markets. However, there are several aspects that need to be addressed in order to maintain competitiveness in the long term. Estonian dairy farms need to increase their total factor productivity. The negative trends in the declining lifespan of dairy cows and declining content of milk components should be stopped. The Estonian dairy processing industry needs to increase labour productivity and value per kg of processed milk. To avoid the negative effects of specialisation on certain products and markets, the portfolio of export markets and products should be expanded. The EU dairy market is going through deregulation, and farm payments in Estonia fell in 2014. This is not the first time in 20 years that agricultural policy has not been overly protective of the dairy sector. Therefore, the future competitiveness of the Estonian dairy sector depends mainly on its adaptive capacity in the light of changing markets, policies and institutions

    High-visibility interference fringes with femtosecond laser radiation

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    We propose and experimentally demonstrate an interferometer for femtosecond pulses with spectral bandwidth about 100 nm. The scheme is based on a Michelson interferometer with a dispersion compensating module. A diffractive lens serves the purpose of equalizing the optical-path-length difference for a wide range of frequencies. In this way, it is possible to register high-contrast interference fringes with micrometric resolution over the whole area of a commercial CCD sensor for broadband femtosecond pulse

    RENTOWNOƚĆ EKONOMICZNA WEDƁUG WIELKOƚCI GOSPODARSTWA W ESTOƃSKICH GOSPODARSTWACH RODZINNYCH

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    Small farms are subject to a wide range of influences on their viability including economic, policy and regulatory drivers as well as internal farm household drivers of change. Small farms have experienced a decline in numbers compared to large farms. The main task of the paper is to determine the share of viable farms of different size groups in Estonia, exploring the factors that are associated with economically viable farms. For determination of the share of viable farms of different size groups the opportunity-cost-based approach is used. Farm viability is estimated by using the data from the Estonian Farm Accounting Data Network. The results indicate that the economic viability of Estonian farms has slightly increased, but the share of viable farms has decreased. Smaller farms’ economic viability is declining, many of them are economically vulnerable. Smaller farms’ capability to survive and develop by using the available resources is lower compared to larger farms.Na rentownoƛć maƂych gospodarstw ma wpƂyw wiele czynnikĂłw, wƂączając w to czynniki gospodarcze, polityczne i regulacyjne, a takĆŒe czynniki wewnętrzne powodujące zmiany w gospodarstwie rolnym. MaƂe gospodarstwa odnotowaƂy spadek liczby w porĂłwnaniu z duĆŒymi gospodarstwami. GƂównym zadaniem niniejszego opracowania jest okreƛlenie udziaƂu rentownych gospodarstw rĂłĆŒnej wielkoƛci w Estonii, badając czynniki związane z rentownymi ekonomicznie gospodarstwami. Do okreƛlenia udziaƂu rentownych gospodarstw rĂłĆŒnej wielkoƛci stosuje się podejƛcie oparte na kosztach alternatywnych. Rentownoƛć gospodarstw szacowana jest na podstawie danych z estoƄskiego Systemu Zbierania i Wykorzystywania Danych Rachunkowych z Gospodarstw Rolnych. Wyniki wskazują, ĆŒe rentownoƛć ekonomiczna estoƄskich gospodarstw nieznacznie wzrosƂa, ale zmalaƂ udziaƂ rentownych gospodarstw rolnych. Rentownoƛć ekonomiczna mniejszych gospodarstw maleje, wiele z nich jest zagroĆŒonych gospodarczo. Zdolnoƛć mniejszych gospodarstw do przetrwania i rozwoju dzięki wykorzystaniu dostępnych zasobĂłw jest niĆŒsza w porĂłwnaniu z większymi gospodarstwami

    Economic Viability by Farm Size of Estonian Family Farms

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    Small farms are subject to a wide range of influences on their viability including economic, policy and regulatory drivers as well as internal farm household drivers of change. Small farms have experienced a decline in numbers compared to large farms. The main task of the paper is to determine the share of viable farms of different size groups in Estonia, exploring the factors that are associated with economically viable farms. For determination of the share of viable farms of different size groups the opportunity-cost-based approach is used. Farm viability is estimated by using the data from the Estonian Farm Accounting Data Network. The results indicate that the economic viability of Estonian farms has slightly increased, but the share of viable farms has decreased. Smaller farms’ economic viability is declining, many of them are economically vulnerable. Smaller farms’ capability to survive and develop by using the available resources is lower compared to larger farms

    Efficiency and productivity change of Estonian dairy farms from 2001 - 2009

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    The purpose of this paper is to analyse productivity change of Estonian dairy farms during the period 2001-2009. Data envelopment analysis (DEA) was used to estimate the technical efficiency of producers and Malmquist productivity index for analysis of productivity change. Estonian FADN data was used in analysis. Performed analysis indicated that Estonian EU accession in 2004 increased considerably total factor productivity. Farm gate milk prices have considerable effect on total factor productivity change. Number of cows and milk yield has positive and dependence on subsidies, stocking density and capital to working hours ratio have negative effects on total factor productivity change

    Efficiency and productivity change of Estonian dairy farms from 2001 - 2009

    No full text
    The purpose of this paper is to analyse productivity change of Estonian dairy farms during the period 2001-2009. Data envelopment analysis (DEA) was used to estimate the technical efficiency of producers and Malmquist productivity index for analysis of productivity change. Estonian FADN data was used in analysis. Performed analysis indicated that Estonian EU accession in 2004 increased considerably total factor productivity. Farm gate milk prices have considerable effect on total factor productivity change. Number of cows and milk yield has positive and dependence on subsidies, stocking density and capital to working hours ratio have negative effects on total factor productivity change.Malmquist productivity index, technical efficiency, technical change, data envelopment analysis, dairy production, Livestock Production/Industries, Productivity Analysis,

    Maaelu arengu aruanne

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    AastaraamatudMe keegi ei soovi vaid nelja linna koondunud Eestit. AastapĂ€evad tagasi, kohtumisel Polli aiandusuuringute keskuses, tutvustasid Eesti MaaĂŒlikooli teadlased mulle mĂ”tet koostada maaelu arengu aruanne, mis hindaks arenguid Eesti maaelus iseseisvuse taastamise jĂ€rel ning vaataks ka tulevikku. Pidasin seda oluliseks, sest peame uurima, milliseid vĂ”imalusi tuleks kasutada maaelu arendamiseks. Eesti ees on kĂŒsimus, kuidas me saame kujundada maapiirkondades – hoolimata vĂ€hesest rahvaarvust ja madalast elanikkonna tihedusest – elukeskkonna, kus inimesed tahavad ja saavad elada ning kuhu nad tahavad tagasi tulla. Kindlasti tĂ€hendab see arenenud taristut, turvatunnet, arstiabi kĂ€ttesaadavust, vĂ”imalust saada head haridust. Maaelust ja regionaalpoliitikast laiemalt kĂ”neledes ei saa me mĂ”elda ainult traditsioonilistele maapiirkondadele, kĂŒladele vĂ”i valdadele. TĂ€helepanu tuleb pöörata ka neile linnadele, mis suudavad olla oma piirkonna arengu vedajateks. Ma ei mĂ”tle Tallinnale, PĂ€rnule, Tartule ja JĂ”hvile, kuhu riigiasutused koondavad oma keskused. Ma mĂ”tlen siin traditsioonilisi maakonnakeskusi. Selleks on oluline avaliku sektori, ĂŒldisemalt öeldes Eesti riigi tegevus ja nĂ€htav kohalolek ning panus maakondades. See on iga piirkonna sotsiaalmajandusliku arengu ĂŒks vedajaid ja seotud vahetult inimest puudutavate teenuste kĂ€ttesaadavusega. Erinevad uuringud ja ka ajaloolised kogemused nĂ€itavad – korraliku taristu ĂŒmber koondub elu. Tugev taristu tĂ€hendab aga kvaliteetsete teenuste kĂ€ttesaadavust kĂ”ikjal Eestis, sellest peab lĂ€htuma riik avaliku halduse kujundamisel. Elamine LÀÀnemaal vĂ”i VĂ”rumaal ei tohi inimest Eesti riigist eraldada ega muuta Eesti riiki talle kaugemaks. Me peame samuti mĂ”tlema riigiasutuste olemasolule vĂ€ljaspool Eesti mĂ”istes suuremaid linnu. Alati pole ―optimeerimine‖ meie rahvale optimaalseim lahendus. KĂ”ike ei saa mÔÔta vaid kokkuhoitud eurodes. Muidu saaks peagi loogiliselt ka kĂŒsida: kas riigita poleks veelgi odavam ja optimaalsem. Pigem otsigu ka riik vĂ”imalusi pakkuda vĂ€iksemateski kohtades tööd haritud inimestele, mis aitab otseselt kaasa investeeringute ja ettevĂ”tluse tulekule piirkonda. Loodetavasti ei soovi me keegi Eestit, mis on koondunud vaid nelja linna. See tĂ€hendab aga teineteist austavat koostööd riigi ja omavalitsuste vahel, kuid ka kĂ”rgkoolide panust, inimeste kaasarÀÀkimist ja nende Ă€rakuulamist, et leida ĂŒheskoos viisid ja vĂ”imalused, kuidas toetada maaelu mitmekesistumist ja seelĂ€bi kestmist. Just maaelu mitmekesistamine on ĂŒheks vĂ”tmeks, mis aitab kohapeal elu edendada. Soodsa ettevĂ”tluskliima loomine erinevate mikro- ja vĂ€ikeettevĂ”tetele peamiselt tööstuse vallas ning regionaalsetele vajadustele vastavate töökohtade hulk nĂ€itab 21. sajandil maaelu arengutaset ja piirkonna heaolu. Selleks on kindlasti oluline lĂ€bi mĂ”elda ja lĂ€bi arutada ka omavalitsuste otsuste mĂ”ju valla vĂ”i linna arengule, koostada parimat mĂ”ju omavate otsuste ĂŒlevaade – hea eeskuju – kolleegidele kasutamiseks ja hindamiseks. Muidugi lisandub siia igas piirkonnas oma kohalike tootjate kaasamine, kasvĂ”i seelĂ€bi, et just nemad varustaksid maakonna koolisööklaid toiduga. LĂ”puks on meil valida kahe suuna vahel: kas edendame ja hoiame aktiivselt kohalikku elu, kasutades ka Euroopa lĂ”imumisega pakutud vĂ”imalusi vĂ”i siis laseme passiivselt minna elul lihtsalt oma teed. TĂ€nan kĂ”iki maaelu arengu aruande koostajaid ja soovin head kaasamĂ”tlemist lugejatele. Toomas Hendrik Ilves Vabariigi President Kadriorus, 7. detsembril 2011Lugupeetud maaelu arengu aruande lugeja. IgaĂŒks meist omab teatud suhet Eesti maaellu. Kas siis ise maal elades, töötades vĂ”i omades sugulasi ja sĂ”pru erinevates piirkondades. Taasiseseisvunud Eesti Vabariigis on toimunud vĂ€ga suured muutused, kuid ilmselt ĂŒhed suuremad muutused on aset leidnud maalistes piirkondades. MĂ€letame ju hĂ€sti, kui palju oli pĂ”llumajandustöötajaid ja kui palju elanikke maapiirkondades. Praeguseks on pĂ”llu- ja metsamajanduslikel aladel nagu ka töötlevas tööstuses toimunud tohutud muutused just tööviljakuse osas, mis omakorda on viinud inimeste lahkumiseni maalt, eelkĂ”ige kaugematest valdadest. Muutused inimeste paiknemises, nende tegevusvaldkondades jne on mĂ”jutanud mitte ainult ĂŒksikute omavalitsuste tegevust, vaid terveid piirkondi, muutes osa neist inimestele veelgi atraktiivsemaks, nagu nĂ€iteks linnade lĂ€hipiirkonnad, aga mis on kurvem – jĂ€tnud vĂ€iksema konkurentsivĂ”imega piirkonnad ĂŒsna tĂŒhjaks, nii et nende konkurentsi- ja inimeste tagasitoomise vĂ”ime jĂ€rjest langes. Oleme jĂ”udnud teatud uude tasakaalustaadiumi, mida on otstarbekas analĂŒĂŒsida, et selle alusel oleks vĂ”imalik teha pika mĂ”juga otsuseid. Me vĂ”ime ja peaksime aga vaatlema tekkinud probleeme mitte murena, vaid hoopis uute vĂ”imalustena, mis vĂ”imaldavad targa tegutsemise juures maaelu tulevikus hoopis kiirendada. Selleks ongi Teie kĂ€es olev materjal vajalik, et vaadata korraks tagasi ja seada siis sammud edasi, vĂ€ltides kunagi tehtud vigu. Loodame, et antud materjalist on kasu meie tulevikuanalĂŒĂŒside tegemisel ja otsuste Ă”igsuse kontrollimisel. Samas oleks vajalik, et selline olukorra jĂ€lgimine erinevates maaelu valdkondades muutuks iga-aastaseks. See muudaks ka otsustuskogudel protsesside jĂ€lgimise lihtsamaks ja otsustuste tegemise kergemaks. Soovin kĂ”igile avastamist kĂ€esolevast aruandest ja edu siit saadud ideede rakendamisel. Lugupidamisega Mait Klaassen, Eesti MaaĂŒlikooli rektorSaateks. Inimese elukeskkond, tema vĂ”imalused ja valikud – need teemad on pĂ€lvinud paljude uurijate tĂ€helepanu ja ajendanud looma uusi teadussuundi. Kas Eestimaal elava inimese elukeskkond vĂ”imaldab asukohast olenemata tunda end ĂŒhiskonna tĂ€isvÀÀrtusliku liikmena ja kogeda sellest rahulolu? Teadlased on kindlaks teinud, et inimese elukeskkond ja selle korraldus mĂ”jutab otseselt tema valikuid. Mis on siis maaelu ja mis eristab seda linnaelust? Mida mĂ”istame maaelu arengu all ning kuidas seda arengut mÔÔta ja mĂ”jutada? Need on teemad, mis vajavad lahtirÀÀkimist. Maaelus toimunud reformide tulemusena on aset leidnud mitmed struktuursed muutused nii elanikkonna tööga kindlustamisel kui ka ettevĂ”tlussektorites. Viimase 20 aasta jooksul on Eesti maaelus muutunud oluliselt ka teenuste kĂ€ttesaadavus ja kvaliteet. Eeltoodu ĂŒhe peamise pĂ”hjusena vĂ”ib esile tuua vĂ€heneva rahvaarvu ning suhteliselt hĂ”reda asustustiheduse maapiirkondades. Siinkohal tekivad mitmed kĂŒsimused: kas suudame maapiirkondades tagada elukvaliteedi kĂ”igile seal elavatele inimestele; kas elukeskkond erinevates Eesti piirkondades on sarnane; kas saame mĂ”jutada protsesse, mis saavad alguse vĂ€ikesest rahvaarvust? Need on kĂŒsimused, mille pĂ€rast valutame sĂŒdant ja millele tahame saada vastuseid. Maa on meid sajandeid toitnud, tĂ€napĂ€eval on maa muutunud rohkem ka konkureerivaks ressursiks erinevate valdkondade vahel. Maaelu ilma maata ei ole vĂ”imalik ette kujutada. Kuid kas meil on maal sĂ€ilinud piisaval mÀÀral toidutootmine ja metsandus kui traditsioonilised tegevusvaldkonnad? Kas meie maapiirkonna elanikud leiavad rakendust ja tööd oma kodukandis vĂ”i on sunnitud liikuma erinevate piirkondade vahel, sest lĂ€heduses ei ole tagatud töökohad pereliikmetele, koolid asuvad elukohast kaugel jms? Nendele kĂŒsimustele tahame senisest enam pöörata avalikkuse tĂ€helepanu ja neile kĂŒsimustele otsitakse vastuseid ka kĂ€esolevas I maaelu arengu aruandes. Maaelu on igati oluline valdkond, vÀÀrimaks enamat avalikkuse tĂ€helepanu ja diskussiooni – see on aruande koostajate kindel seisukoht. Rando VĂ€rnik, Eesti MaaĂŒlikooli majandus- ja sotsiaalinstituudi direktorMaaelu arengu aruande koostamist finantseeris Eesti haridus- ja teadusministeerium.TrĂŒkise vĂ€ljaandmist toetas Eesti pĂ”llumajandusministeeriu
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