992 resultados para Spectral Gap Problems
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The practice of social entrepreneurship already exists for a long time but the concept is quite new and has more recently raised a growing interest among academics. However, the majority of researches and considerations about the subject have taken a strong positive concern by omitting some sort of a critical reflection. The idea of this study is to consider the gap between the very optimistic and the more precautious concerns about social entrepreneurship. It means presenting the advantages and downsides connected to the topic in the business, public and third sector. The aim is to help the reader building his/her own belief on social entrepreneurship by considering the positive and negative sides of social entrepreneurship. Hence, the research is intended to take a critical step and aims to answer to the following research questions: Shall we believe in social entrepreneurship? What are the reasons for believing or not in social entrepreneurship taking into account the advantages and possible risks of it in the business, public, and third sector? The theoretical framework consists of the comparison between the promising and precautious sides about social entrepreneurship for private, public and non-governmental organizations including the actors or participants inside these sectors. The empirical part is conducted using a qualitative method. Personal interviews of experts in the fields of business, public and third sectors were handled. The purpose of this approach is to compare the critics in theory with the experience of persons dealing with social entrepreneurship. The results from the interviews revealed that in general, reasons for believing in social entrepreneurship prevail over critics about the subject. Social entrepreneurship may not yet represent a full performing business. Concerns for weakening the public power and putting aside the interests of communities in need may exist too. Furthermore, naïve and extra liberal ways of thinking or doing can lead to practices going in opposition with initial social objectives. Nevertheless, problems about social entrepreneurship would be mainly due to the young age of the movement. Time and experience would give better foundations and results to social entrepreneurs. Critics about social entrepreneurship could also easily be done to any sorts of business. Overall, the positive considerations of social entrepreneurship with skillful, motivated and responsible actors could represent some useful tools for enterprises, governments and charities. Some tools among many other possibilities to help people in need.
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The current knowledge of light quality effects on plant morphogenesis and development represents a new era of understanding on how plant communities perceive and adjust to available resources. The most important consequences of light quality cues, often mediated by decreasing in red far-red ratios with respect to the spectral composition of incident sunlight radiation, affecting weed-crop interaction are the increased plant height and shoot to root ratio in anticipation of competition by light quantity, water or nutrients. Although the concepts related to light quality have been extensively studied and several basic process of this phenomenon are well known, little applications of photomorphogenic signaling currently are related to agricultural problems or weed management. The objectives of this review are to describe how light quality change can be a triggering factor of interspecific interference responses, to analyze how this phenomenon can be used to predict weed interference, to reevaluate the critical periods of interference concept, and to discuss its potential contribution towards developing more weed competitive crop varieties. Knowledge on light quality responses involved in plant sensing of interspecific competition could be used to identify red/far-red threshold values, indicating when weed control should be started. Light quality alterations by weeds can affect grain crop development mainly in high yielding fields. Unlike the traditional concept or the critical period of competition, light quality mediated interference implies that the critical period for weed control could start before the effects of direct resource (water, nutrients and available light) limitation actually occur. The variability in light quality responses among crop genotypes and the identification of mutants insensitive to light quality effects indicate that this characteristic can be selected or modified to develop cultivars with enhanced interspecific interference ability. Knowledge on light quality-elicited responses represents a new possibility to understand the underlying biology of interspecific interference, and could be used in the development of new weed management technologies.
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Vaikka liiketoimintatiedon hallintaa sekä johdon päätöksentekoa on tutkittu laajasti, näiden kahden käsitteen yhteisvaikutuksesta on olemassa hyvin rajallinen määrä tutkimustietoa. Tulevaisuudessa aiheen tärkeys korostuu, sillä olemassa olevan datan määrä kasvaa jatkuvasti. Yritykset tarvitsevat jatkossa yhä enemmän kyvykkyyksiä sekä resursseja, jotta sekä strukturoitua että strukturoimatonta tietoa voidaan hyödyntää lähteestä riippumatta. Nykyiset Business Intelligence -ratkaisut mahdollistavat tehokkaan liiketoimintatiedon hallinnan osana johdon päätöksentekoa. Aiemman kirjallisuuden pohjalta, tutkimuksen empiirinen osuus tunnistaa liiketoimintatiedon hyödyntämiseen liittyviä tekijöitä, jotka joko tukevat tai rajoittavat johdon päätöksentekoprosessia. Tutkimuksen teoreettinen osuus johdattaa lukijan tutkimusaiheeseen kirjallisuuskatsauksen avulla. Keskeisimmät tutkimukseen liittyvät käsitteet, kuten Business Intelligence ja johdon päätöksenteko, esitetään relevantin kirjallisuuden avulla – tämän lisäksi myös dataan liittyvät käsitteet analysoidaan tarkasti. Tutkimuksen empiirinen osuus rakentuu tutkimusteorian pohjalta. Tutkimuksen empiirisessä osuudessa paneudutaan tutkimusteemoihin käytännön esimerkein: kolmen tapaustutkimuksen avulla tutkitaan sekä kuvataan toisistaan irrallisia tapauksia. Jokainen tapaus kuvataan sekä analysoidaan teoriaan perustuvien väitteiden avulla – nämä väitteet ovat perusedellytyksiä menestyksekkäälle liiketoimintatiedon hyödyntämiseen perustuvalle päätöksenteolle. Tapaustutkimusten avulla alkuperäistä tutkimusongelmaa voidaan analysoida tarkasti huomioiden jo olemassa oleva tutkimustieto. Analyysin tulosten avulla myös yksittäisiä rajoitteita sekä mahdollistavia tekijöitä voidaan analysoida. Tulokset osoittavat, että rajoitteilla on vahvasti negatiivinen vaikutus päätöksentekoprosessin onnistumiseen. Toisaalta yritysjohto on tietoinen liiketoimintatiedon hallintaan liittyvistä positiivisista seurauksista, vaikka kaikkia mahdollisuuksia ei olisikaan hyödynnetty. Tutkimuksen merkittävin tulos esittelee viitekehyksen, jonka puitteissa johdon päätöksentekoprosesseja voidaan arvioida sekä analysoida. Despite the fact that the literature on Business Intelligence and managerial decision-making is extensive, relatively little effort has been made to research the relationship between them. This particular field of study has become important since the amount of data in the world is growing every second. Companies require capabilities and resources in order to utilize structured data and unstructured data from internal and external data sources. However, the present Business Intelligence technologies enable managers to utilize data effectively in decision-making. Based on the prior literature, the empirical part of the thesis identifies the enablers and constraints in computer-aided managerial decision-making process. In this thesis, the theoretical part provides a preliminary understanding about the research area through a literature review. The key concepts such as Business Intelligence and managerial decision-making are explored by reviewing the relevant literature. Additionally, different data sources as well as data forms are analyzed in further detail. All key concepts are taken into account when the empirical part is carried out. The empirical part obtains an understanding of the real world situation when it comes to the themes that were covered in the theoretical part. Three selected case companies are analyzed through those statements, which are considered as critical prerequisites for successful computer-aided managerial decision-making. The case study analysis, which is a part of the empirical part, enables the researcher to examine the relationship between Business Intelligence and managerial decision-making. Based on the findings of the case study analysis, the researcher identifies the enablers and constraints through the case study interviews. The findings indicate that the constraints have a highly negative influence on the decision-making process. In addition, the managers are aware of the positive implications that Business Intelligence has for decision-making, but all possibilities are not yet utilized. As a main result of this study, a data-driven framework for managerial decision-making is introduced. This framework can be used when the managerial decision-making processes are evaluated and analyzed.
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Poster at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014
Resumo:
Pelastuslaitosten liiketoimintatiedonhallinnalla, tietoperusteisuudella ja tietojohtamisella on tulevaisuudessa merkittävä rooli päätettäessä palveluista. Julkisen pelastustoimen kuntien liikelaitoksina ja eriytettyinä taseyksiköinä toimivien pelastuslaitosten haasteet tulevat olemaan jatkossa tehokkaiden ja vaikuttavien palveluiden strategisessa johtamisessa ja suunnittelussa. Näistä asioista päättäminen on kriittinen vaihe onnistumisen kannalta. Päätöksenteko eri tasoilla tarvitsee tuekseen toiminnasta ja palveluista kanavoitua analysoitua tietoa. Asiakastarpeesta lähtevä vaikuttavuus ja laatu korostuvat. Liiketoimintatiedonhallinta ja tietoperusteisuus haastavat pelastuslaitoksen johtamisjärjestelmän. Johtamisen kyvykkyys ja henkilöstön osaaminen ovat tietoperusteisuuden ja tiedonhallinnan keskiössä. Systemaattisen liiketoimintatiedonhallinnan ja tietoperusteisuuden erottaa perinteisestä virkamiehen tietojen hyväksikäytöstä käsitteen kokonaisvaltaisuus ja järjestelmällisyys kaikessa tiedollisessa toiminnassa. Tämä kattaa tietojärjestelmät, mittarit, prosessit, strategian suunnitelmat, asiakirjat, raportoinnin, kehittämisen ja tutkimuksen. Liiketoimin-tatiedonhallinta ja tietojohtaminen linkittävät kaiken toisiinsa muodostaen keskinäisriippuvaisen yhtenäisen järjestelmän ja kokonaisvaltaisen ymmärryksen. Tutkimukseni on laadullinen tutkimus jossa tiedon keruu ja analysointi on toteutettu toisiaan tukevilla tutkimusotteilla. Metodologia nojaa teorialähtöiseen systemaattiseen analyysiin, jossa on valikoituja osia sisällön analyysistä. Tutkimuksessa on käytetty aineisto- ja menetelmätriangulaatioita. Tutkimuksen aineisto on kerätty teemahaastatteluilla valittujen kohde pelastuslaitosten asiantuntijoilta palveluiden päätös- ja suunnittelutasolta, johtoryhmistä ja joh-tokunnista. Haastatteluja varten tutkija on tutustunut kohdepelastuslaitosten palveluita mää-rittävään tiedolliseen dokumentaatioon kuten palvelutasopäätöksiin ja riskianalyyseihin. Ai-neisto keruun kohteiksi valikoitui pääkaupunkiseudun alueen pelastuslaitokset: Helsingin kaupungin pelastuslaitos sekä Itä-, Keski- ja Länsi-Uudenmaan pelastuslaitokset. Tulosten mukaan pelastuslaitosten keskeiset liiketoimintatiedonhallinnan esteet muodostuvat johtamisen ongelmista, organisaation muutosvastarinnasta ja päätöksenteon tietoperusteen puutteesta. Nämä ilmenevät strategisen johtamisen puutteina, vaikuttavuuden mittaamisen sekä tiedon jalostamisen ongelmina. Keskeistä tiedollista yhdistävää ja linkittävää tekijää ei tunnisteta ja löydetä. Tiedollisessa liiketoimintatiedonhallinnan prosessityössä voisi olla tulos-ten mukaan mahdollisuuksia tämän tyhjiön täyttämiseen. Pelastuslaitoksille jää tulevaisuudessa valinta suunnasta johon ne haluavat edetä tiedonhal-linnan, tietojohtamisen ja tietoperusteisuuden kanssa. Tämä vaikuttaa kehitykseen ja tavoitteeseen keskeisistä palveluiden päätöksentekoa tukevista johtamis- ja tietojärjestelmistä, tietoa kokoavista ja luovista dokumenteista sekä organisaation joustavasta rakenteesta. Tietoprosessiin, tiedon prosessimaiseen johtamiseen ja systemaattiseen tiedonhallintaan meneminen vaikuttaa tutkimuksen tulosten mukaan lupaavalta mahdollisuudelta. Samalla se haastaa pelauslaitokset suureen kulttuuriseen muutokseen ja asettaa uusien vaikuttavuusmittareiden tuottaman tiedon ennakoivan hyväksynnän vaateen strategiselle suunnittelulle. Tämä vaatii pelastuslaitosten johdolta ja henkilöstöltä osaamista, yhteisymmärrystä, muutostarpeiden hyväksyntää sekä asiakkaan asettamista vaikuttavuuden keskiöön.
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Leaf CO2 assimilation (A) as a function of photosynthetic photon flux density (Q) or intercellular CO2 concentration (Ci) and chlorophyll fluorescence measurements were carried out on four tropical woody species growing in forest gap and understorey (Bauhinia forficata Link. and Guazuma ulmifolia Lam. as pioneers, and Hymenaea courbaril L. and Esenbeckia leiocarpa Engl. as non-pioneers). Chlorophyll fluorescence indicated similar acclimation capacities of photochemical apparatus to contrasting light environments irrespective to plant species. Maximum CO2 assimilation and quantum yield derived from A/Q curves indicated higher photosynthetic capacity in pioneer than in non-pioneer species in forest gap. However, the differences among species did not show a straightforward relation with their successional status regarding data derived from A/Q curves under understorey conditions. Both successional groups are able to sustain positive carbon balance under contrasting natural light availabilities, modifying photochemical and biochemical photosynthetic traits with similar phenotypic plasticity capacity.
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Spectral sensitivities of visual systems are specified as the reciprocals of the intensities of light (quantum fluxes) needed at each wavelength to elicit the same criterion amplitude of responses. This review primarily considers the methods that have been developed for electrophysiological determinations of criterion amplitudes of slow-wave responses from single retinal cells. Traditional flash methods can require tedious dark adaptations and may yield erroneous spectral sensitivity curves which are not seen in such modifications as ramp methods. Linear response methods involve interferometry, while constant response methods involve manual or automatic adjustments of continuous illumination to keep response amplitudes constant during spectral scans. In DC or AC computerized constant response methods, feedback to determine intensities at each wavelength is derived from the response amplitudes themselves. Although all but traditional flash methods have greater or lesser abilities to provide on-line determinations of spectral sensitivities, computerized constant response methods are the most satisfactory due to flexibility, speed and maintenance of a constant adaptation level
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Most cells exchange ions and small metabolites via gap junction channels. These channels are made of two hemichannels (connexons), each formed by the radial arrangement of six connexin (Cx) proteins. Connexins span the bilayer four times (M1-M4) and have both amino- and carboxy-termini (NT, CT) at the cytoplasmic side of the membrane, forming two extracellular loops (E1, E2) and one inner (IL) loop. The channels are regulated by gates that close with cytosolic acidification (e.g., CO2 treatment) or increased calcium concentration, possibly via calmodulin activation. Although gap junction regulation is still unclear, connexin domains involved in gating are being defined. We have recently focused on the CO2 gating sensitivity of Cx32, Cx38 and various mutants and chimeras expressed in Xenopus oocytes and studied by double voltage clamp. Cx32 is weakly sensitive to CO2, whereas Cx38 is highly sensitive. A Cx32 chimera containing the second half of the inner loop (IL2) of Cx38 was as sensitive to CO2 as Cx38, indicating that this domain plays an important role. Deletion of CT by 84% did not affect CO2 sensitivity, but replacement of 5 arginines (R) with sparagines (N) at the beginning of CT (C1) greatly enhanced the CO2 sensitivity of Cx32. This suggests that whereas most of CT is irrelevant, positive charges of C1 maintain the CO2 sensitivity of Cx32 low. As a hypothesis we have proposed a model that involves charge interaction between negative residues of the beginning of IL1 and positive residues of either C1 or IL2. Open and closed channels would result from IL1-C1 and IL1-IL2 interactions, respectively
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Gap junctions are constituted by intercellular channels and provide a pathway for transfer of ions and small molecules between adjacent cells of most tissues. The degree of intercellular coupling mediated by gap junctions depends on the number of gap junction channels and their activity may be a function of the state of phosphorylation of connexins, the structural subunit of gap junction channels. Protein phosphorylation has been proposed to control intercellular gap junctional communication at several steps from gene expression to protein degradation, including translational and post-translational modification of connexins (i.e., phosphorylation of the assembled channel acting as a gating mechanism) and assembly into and removal from the plasma membrane. Several connexins contain sites for phosphorylation for more than one protein kinase. These consensus sites vary between connexins and have been preferentially identified in the C-terminus. Changes in intercellular communication mediated by protein phosphorylation are believed to control various physiological tissue and cell functions as well as to be altered under pathological conditions.
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It is well known that saccadic reaction times (SRT) are reduced when the target is preceded by the offset of the fixation point (FP) - the gap effect. Some authors have proposed that the FP offset also allows the saccadic system to generate a separate population of SRT, the express saccades. Nevertheless, there is no agreement as to whether the gap effect and express responses are also present for manual reaction times (MRT). We tested the gap effect and the MRT distribution in two different conditions, i.e., simple and choice MRT. In the choice MRT condition, subjects need to identify the side of the stimulus and to select the appropriate response, while in the simple MRT these stages are not necessary. We report that the gap effect was present in both conditions (22 ms for choice MRT condition; 15 ms for simple MRT condition), but, when analyzing the MRT distributions, we did not find any clear evidence for express manual responses. The main difference in MRT distribution between simple and choice conditions was a shift towards shorter values for simple MRT.
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The along-scan radiometric gradient causes severe interpretation problems in Landsat images of tropical forests. It creates a decreasing trend in pixel values with the column number of the image. In practical applications it has been corrected assuming the trend to be linear within structurally similar forests. This has improved the relation between floristic and remote sensing information, but just in some cases. I use 3 Landsat images and 105 floristic inventories to test the assumption of linearity, and to examine how the gradient and linear corrections affect the relation between floristic and Landsat data. Results suggest the gradient to be linear in infrared bands. Also, the relation between floristic and Landsat data could be conditioned by the distribution of the sampling sites and the direction in which images are mosaicked. Additionally, there seems to be a conjunction between the radiometric gradient and a natural east-west vegetation gradient common in Western Amazonia. This conjunction might have enhanced artificially correlations between field and remotely-sensed information in previous studies. Linear corrections may remove such artificial enhancement, but along with true and relevant spectral information about floristic patterns, because they can´t separate the radiometric gradient from a natural one.
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In today’s world because of the rapid advancement in the field of technology and business, the requirements are not clear, and they are changing continuously in the development process. Due to those changes in the requirements the software development becomes very difficult. Use of traditional software development methods such as waterfall method is not a good option, as the traditional software development methods are not flexible to requirements and the software can be late and over budget. For developing high quality software that satisfies the customer, the organizations can use software development methods, such as agile methods which are flexible to change requirements at any stage in the development process. The agile methods are iterative and incremental methods that can accelerate the delivery of the initial business values through the continuous planning and feedback, and there is close communication between the customer and developers. The main purpose of the current thesis is to find out the problems in traditional software development and to show how agile methods reduced those problems in software development. The study also focuses the different success factors of agile methods, the success rate of agile projects and comparison between traditional and agile software development.
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Gap junctions are clusters of intercellular channels directly connecting the cytoplasm of adjacent cells. These channels are formed by proteins named connexins and are present in all metazoan organisms where they serve diverse functions ranging from control of cell growth and differentiation to electric conduction in excitable tissues. In this overview we describe the presence of connexins in the cardiovascular and lympho-hematopoietic systems giving the reader a summary of the topics to be covered throughout this edition and a historical perspective of the discovery of gap junctions in the immune system.