990 resultados para Limited society


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This paper presents a study on the dynamics of the rattling problem in gearboxes under non-ideal excitation. The subject has being analyzed by a number of authors such as Karagiannis and Pfeiffer (1991), for the ideal excitation case. An interesting model of the same problem by Moon (1992) has been recently used by Souza and Caldas (1999) to detect chaotic behavior. We consider two spur gears with different diameters and gaps between the teeth. Suppose the motion of one gear to be given while the motion of the other is governed by its dynamics. In the ideal case, the driving wheel is supposed to undergo a sinusoidal motion with given constant amplitude and frequency. In this paper, we consider the motion to be a function of the system response and a limited energy source is adopted. Thus an extra degree of freedom is introduced in the problem. The equations of motion are obtained via a Lagrangian approach with some assumed characteristic torque curves. Next, extensive numerical integration is used to detect some interesting geometrical aspects of regular and irregular motions of the system response.

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We apply the Bogoliubov Averaging Method to the study of the vibrations of an elastic foundation, forced by a Non-ideal energy source. The considered model consists of a portal plane frame with quadratic nonlinearities, with internal resonance 1:2, supporting a direct current motor with limited power. The non-ideal excitation is in primary resonance in the order of one-half with the second mode frequency. The results of the averaging method, plotted in time evolution curve and phase diagrams are compared to those obtained by numerically integrating of the original differential equations. The presence of the saturation phenomenon is verified by analytical procedures.

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In this work a particular system is investigated consisting of a pendulum whose point of support is vibrated along a horizontal guide by a two bar linkage driven from a DC motor, considered as a limited power source. This system is nonideal since the oscillatory motion of the pendulum influences the speed of the motor and vice-versa, reflecting in a more complicated dynamical process. This work comprises the investigation of the phenomena that appear when the frequency of the pendulum draws near a secondary resonance region, due to the existing nonlinear interactions in the system. Also in this domain due to the power limitation of the motor, the frequency of the pendulum can be captured at resonance modifying completely the final response of the system. This behavior is known as Sommerfeld effect and it will be studied here for a nonlinear system.

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Software plays an important role in our society and economy. Software development is an intricate process, and it comprises many different tasks: gathering requirements, designing new solutions that fulfill these requirements, as well as implementing these designs using a programming language into a working system. As a consequence, the development of high quality software is a core problem in software engineering. This thesis focuses on the validation of software designs. The issue of the analysis of designs is of great importance, since errors originating from designs may appear in the final system. It is considered economical to rectify the problems as early in the software development process as possible. Practitioners often create and visualize designs using modeling languages, one of the more popular being the Uni ed Modeling Language (UML). The analysis of the designs can be done manually, but in case of large systems, the need of mechanisms that automatically analyze these designs arises. In this thesis, we propose an automatic approach to analyze UML based designs using logic reasoners. This approach firstly proposes the translations of the UML based designs into a language understandable by reasoners in the form of logic facts, and secondly shows how to use the logic reasoners to infer the logical consequences of these logic facts. We have implemented the proposed translations in the form of a tool that can be used with any standard compliant UML modeling tool. Moreover, we authenticate the proposed approach by automatically validating hundreds of UML based designs that consist of thousands of model elements available in an online model repository. The proposed approach is limited in scope, but is fully automatic and does not require any expertise of logic languages from the user. We exemplify the proposed approach with two applications, which include the validation of domain specific languages and the validation of web service interfaces.

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Jussi-Pekka Hakkaraisen esitys 24. Kansainvälisessä tieteen-, teknologian ja lääketieteen historian kongressissa (24th International Congress of History of Science, Technology and Medicine) Manchesterissa 26.7.2013

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Taking a realist view that law is one form of politics, this dissertation studies the roles of citizens and organizations in mobilizing the law to request government agencies to disclose environmental information in China, and during this process, how the socio-legal field interacts with the political-legal sphere, and what changes have been brought about during their interactions. This work takes a socio-legal approach and applies methodologies of social science and legal analysis. It aims to understand the paradox of why and how citizens and entities have been invoking the law to access environmental information despite the fact that various obstacles exist and the effectiveness of the new mechanism of environmental information disclosure still remains low. The study is largely based on the 28 cases and eight surveys of environmental information disclosure requests collected by the author. The cases and surveys analysed in this dissertation all occurred between May 2008, when the OGI Regulations and the OEI Measures came into effect, and August 2012 when the case collection was completed. The findings of this study have shown that by invoking the rules of law made by the authorities to demand government agencies disclosing environmental information, the public, including citizens, organizations, law firms, and the media, have strategically created a repercussive pressure upon the authorities to act according to the law. While it is a top-down process that has established the mechanism of open government information in China, it is indeed the bottom-up activism of the public that makes it work. Citizens and organizations’ use of legal tactics to push government agencies to disclose environmental information have formed not only an end of accessing the information but more a means of making government agencies accountable to their legal obligations. Law has thus played a pivotal role in enabling citizen participation in the political process. Against the current situation in China that political campaigns, or politicization, from general election to collective actions, especially contentious actions, are still restrained or even repressed by the government, legal mobilization, or judicialization, that citizens and organizations use legal tactics to demand their rights and push government agencies to enforce the law, become de facto an alternative of political participation. During this process, legal actions have helped to strengthen the civil society, make government agencies act according to law, push back the political boundaries, and induce changes in the relationship between the state and the public. In the field of environmental information disclosure, citizens and organizations have formed a bottom-up social activism, though limited in scope, using the language of law, creating progressive social, legal and political changes. This study emphasizes that it is partial and incomplete to understand China’s transition only from the top-down policy-making and government administration; it is also important to observe it from the bottom-up perspective that in a realistic view law can be part of politics and legal mobilization, even when utterly apolitical, can help to achieve political aims as well. This study of legal mobilization in the field of environmental information disclosure also helps us to better understand the function of law: law is not only a tool for the authorities to regulate and control, but inevitably also a weapon for the public to demand government agencies to work towards their obligations stipulated by the laws issued by themselves.

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Kuntaorganisaatioiden muutokset ovat tulleet Suomessa runsaan parinkymmenen vuoden aikana yhä välttämättömämmiksi sekä globaalien että kansallisten toimintaympäristöjen muuttumisen vuoksi. Niitä tehtäessä on kuitenkin kohdattu suuria vaikeuksia jo muutosprosessien alussa, suunnittelu- ja päätöksentekovaiheessa. Keskityttäessä organisaatiomuutosten tavoitteisiin ja lopputulokseen ovat keinot niihin pääsemiseksi jääneet vaille riittävää huomiota. Tämän väitöskirjatutkimuksen päätavoite on selvittää syitä, jotka edistävät ja haittaavat kuntaorganisaation muutosprosessia. Sekundäärisenä tavoitteena on tarkastella motivaation, toimintakulttuurin, poliittisten ja ideologisten eroavaisuuksien sekä arvojen ja asenteiden vaikutusta muutosprosessiin sen eri vaiheissa sekä erilaisissa olosuhteissa. Tutkimuksessa käytetään kvalitatiivista tutkimusmenetelmää, joka tukeutuu erään kunnan teknisen toimialan muutosprosessiin. Tutkimuksen kohteena olevana ajanjaksona sekä vakaassa että muuttuvassa toimintaympäristössä ovat tuon kunnan teknisen toimialan organisaatiomuotoina olleet virasto, liikelaitos, osakeyhtiö ja toimintojen ulkoistaminen. Empiirisen aineiston sekä niin kansallisten kuin kansainvälisten tutkimusten perusteella pyritään löytämään muutosprosessia vaikeuttavia tekijöitä sekä keinoja vaikuttaa prosessin onnistumiseen. Tapaustutkimuksen aineistona ovat tarkastellun kunnan organisaatiomuutoksia koskevat dokumentit. Niitä on täydennetty haastattelemalla henkilöitä, jotka ovat joko suoraan vaikuttaneet muutokseen tai ainakin olleet siinä kiinteästi mukana. Muutosprosessiin liittyviä haasteita lähestytään prosessitutkimuksen avulla pyrkien selvittämään erilaiset kriittiset tapahtumat ja käännekohdat, syy-yhteydet sekä mahdolliset muutoksia suuntaavat mallit. Vaikka muutoksiin vaikuttavat tekijät ovat tämän tutkimuksen tulosten perusteella pääosin samat kuin mitä on havaittu kansainvälisissä tutkimuksissa, liittyy niihin kuitenkin tutkimuksen tapauskohteessa kansallisia ja osittain paikallisiakin erityispiirteitä. On havaittavissa sekä kansallisten ominaispiirteiden että pohjoismaisen hyvinvointiyhteiskunnan ihanteen vaikutusta ihmisten suhtautumisessa muutosprosessiin sekä käyttäytymiseen sen aikana. Tämän tutkimuksen valossa avoimuus ja oikeudenmukaisuus ovat vahvimmin vaikuttavia tekijöitä kuntaorganisaation muutoksessa. Tämän tutkimuksen teoriatarkastelu pohjautuu tutkimuksiin, jotka ovat kohdistuneet muutosprosesseihin yleensä niin julkishallinnon kuin yksityissektorin organisaatioissa. Vaikka tämän väitöskirjan tutkimuksen fokus on kuntasektorilla, ovat sen tulokset suurelta osin sovellettavissa myös yksityissektorille.

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Radish has developed feral and weedy biotypes, which is a concern for agriculture around the world. In Argentina, it is one of the most widespread and troublesome crop weeds. In Brazil, this species has developed herbicide-resistance to acetohydroxyacid synthase (AHAS) inhibiting herbicides. The objective of this study was to record the presence of herbicide-resistant weedy radish plants in Argentina. In spring 2008, we found a small population of radish at the end of the flowering stage in an imidazolinone-tolerant canola field treated with imazethapyr. Screening and dose-response tests were conducted to two successive generations. They proved the biotype resistant status, and showed extensive survival (between 50 and 80% of control) to the application of a double dose of four AHAS‑inhibiting herbicides from two different chemical families (imidazolinones and sulfonylureas). Dose-response assays exhibited very high resistance for imazethapyr (LD50 = 2452.5 g a.i. ha-1, GR50 = 2926.9 g a.i. ha-1) and intermediate for metsulfuron (LD50 = 3.0 g a.i. ha-1, GR50 = 43.2 g a.i. ha-1). The acquisition of cross-resistance to different herbicide families would confer an adaptive and invasive advantage in agricultural environments to this biotype. Due to the herbicide rotation conducted in the field, the dispersion of this biotype was restricted. This is the first report of resistance in weedy radish in Argentina.

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Can crowdsourcing solutions serve many masters? Can they be beneficial for both, for the layman or native speakers of minority languages on the one hand and serious linguistic research on the other? How did an infrastructure that was designed to support linguistics turn out to be a solution for raising awareness of native languages? Since 2012 the National Library of Finland has been developing the Digitisation Project for Kindred Languages, in which the key objective is to support a culture of openness and interaction in linguistic research, but also to promote crowdsourcing as a tool for participation of the language community in research. In the course of the project, over 1,200 monographs and nearly 111,000 pages of newspapers in Finno-Ugric languages will be digitised and made available in the Fenno-Ugrica digital collection. This material was published in the Soviet Union in the 1920s and 1930s, and users have had only sporadic access to the material. The publication of open-access and searchable materials from this period is a goldmine for researchers. Historians, social scientists and laymen with an interest in specific local publications can now find text materials pertinent to their studies. The linguistically-oriented population can also find writings to delight them: (1) lexical items specific to a given publication, and (2) orthographically-documented specifics of phonetics. In addition to the open access collection, we developed an open source code OCR editor that enables the editing of machine-encoded text for the benefit of linguistic research. This tool was necessary since these rare and peripheral prints often include already archaic characters, which are neglected by modern OCR software developers but belong to the historical context of kindred languages, and are thus an essential part of the linguistic heritage. When modelling the OCR editor, it was essential to consider both the needs of researchers and the capabilities of lay citizens, and to have them participate in the planning and execution of the project from the very beginning. By implementing the feedback iteratively from both groups, it was possible to transform the requested changes as tools for research that not only supported the work of linguistics but also encouraged the citizen scientists to face the challenge and work with the crowdsourcing tools for the benefit of research. This presentation will not only deal with the technical aspects, developments and achievements of the infrastructure but will highlight the way in which user groups, researchers and lay citizens were engaged in a process as an active and communicative group of users and how their contributions were made to mutual benefit.

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Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014

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Pro gradu -tutkimuksen keskeisin tavoite on selvittää perusteita pankin notariaattipalveluiden tarjoajan vastuun laajenemiselle yli välittömän toimeksiantosopimussuhteen. Tutkimus on rajattu vain Suomen oikeuteen ja tutkimusasetelmasta seuraa, että vastuun henkilöllisen ulottuvuuden laajentumisen tilanteista tutkimuksessa perehdytään nimenomaisesti sivullisintressitilanteisiin. Tutkimus on toteutettu lainopillisesti. Suomen laissa ei säädetä suoraan välittömän sopimussuhteen ylittävästä vastuusta, joten lainsäädännön jäädessä vähemmälle korostuvat tutkimuksessa sopimusoikeuden yleiset periaatteet sekä korkeimman oikeuden tulkintakäytäntö ja oikeustieteellinen tutkimus. Tämä johtaa etsimään ja jäsentämään tutkimusongelman kannalta merkityksellisiä oikeusperiaatteita ja reaalisia argumentteja tarkkojen tulkintasuositusten tarjoamisen sijaan. Tutkimus osoittaa, että välittömän sopimussuhteen ylittävää vastuuta tulee arvioida sopimusvastuun normien mukaisesti deliktivastuun sijaan, ja sitä voidaan pitää eräänä sopimusvastuun erityistapauksena. Tutkimuksen pohjalta voidaan todeta, että pankin notariaattipalveluiden tarjoajan vastuu voi ulottua yli toimeksiantosopimussuhteen, jos vastuun syntymistä voidaan puoltaa riittävillä reaalisilla argumenteilla. Tällaisia perusteita ovat muun muassa pankin notariaattipalvelun tarjoajan ja sivullisen välinen erityissuhde ja pankin notariaattipalvelun tarjoajan mahdollisuus ennakoida vahinkoriski. Lisäksi kaksiasianosaissuhteen rajoituksesta poikkeamista voidaan perustella vaihdannan reaalisen rakenteen huomioonottamisella sekä sivulliselle syntyneellä perustellun luottamuksen suojaamisella.

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Riskit ja riskittömyys uhkaavat yksilöitä, käsityötä ja yhteiskuntaa. Käsityökasvatukselleon haaste toimia kulttuurissa, joka tavoittelee täyttä riskittömyyttä. Käsityössä kasvatetaan kekseliäisyyteen ja varautumaan sen aiheuttaman riskin kohtaamiseen sekä ottamaan siitä vastuuta. Tämän tutkimuksen tehtävänä on riskivastuullisuuden mallin rakentamiseksi selvittää, kuinka oppilaiden vastuullisuus selittää riskirajaa käsityön turvallisuuskasvatuksen kulttuurissa. Välinearvojen saavuttamiseksi on siedettävä välineriskiä, joka ei ylitä turvallisuuskulttuurin riskirajaa. Välinearvot ovat välineiden laatua lisääviä ominaisuuksia, joilla pyritään peittämään välineriskejä. Siedettävän riskin rajan ratkaisemiseen tarvitaan tietoa käsityön tuottamisesta ja todellisuutta havainnoivien tiedonalojen tietoa. Viime kädessä ratkaisu tehdään rakentavalla ajattelulla, johon kuuluu välinearvojen tavoittelua ohjaava käsityötaju ja välineriskeihin varautumista ohjaava turvallisuustaju. Käsityössä onnistuminen kannustaa kohti uusia haasteita ja epäonnistumisen riski asettuu mittasuhteisiinsa. Kekseliäässä käsityön kulttuurissa kokeillaan omia ja ympäröivän todellisuuden mahdollisuuksia ottamalla oivaltaen riskejä, jotka saavat aikaan rakentavan kokemuksen riskistä. Käsityö on riskioivallusten oppiaine. Tutkimustehtävän toteuttamiseksi tässä tutkimuksessa rakennetaan uusi riskivastuullisuuden malli, jossa vastuullisuus selittää riskirajaa. Mallin vastaavuutta selvitetään valtakunnallisesti peruskoulun käsityön 6. ja 9. luokan käsityön opetuksessa (n = 393). Aineisto on analysoitu rakenneyhtälöanalyysein konfirmatorisella faktorianalyysilla ja polkumallinnuksella. Tutkimusaineisto ja riskivastuullisuuden malli vastaavat toisiaan. Vastuullisuuden selitysosuus turvallisuustajun ja käsityötajun ratkaisemasta riskirajasta on mallin mukaan 35 %. Oppilaat osoittivat tuntevansa oman tuottamisensa vaikutuksia ja vastuuta niistä. Vastuullisuus osoittautui tärkeäksi riskirajan selittäjäksi, joten käsityön turvallisuuskasvatuksen kulttuuri voi kohota uudelle tasolle riskivastuulliseksi. Käsityön turvallisuuskasvatus on kokonaisvaltaista turvallisuustajun kasvatusta. Riskivastuullisuus luo turvallisuuskulttuuriin yhteisen käsityksen siedettävän riskin rajasta. Oppilaiden mahdollisuuksia kekseliääseen tutkivaan tuottamiseen on vahvistettava eikä rajoitettava. Riskivastuullisessa käsityön turvallisuuskasvatuksen kulttuurissa opettajan tehtävänä ei ole estää mitään tapahtumasta vaan saada mahdollisimman paljon tapahtumaan, sillä vastuullisuus kasvaa vastuuta ottamalla. Se on kasvatuksen – käsityökasvatuksen – keino turvallisuustyössä.

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Presentation at the 12th Bibliotheca Baltica Symposium at Södertörn University Library

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Background: Sick leave prescribing is a common task of doctors and being on sick leave results in notable economic consequences to society. However, there appears to be limited research into this field and the factors affecting sick leave prescribing practices of doctors. Aims: To examine the prescribing of sick leave by doctors and dentists, the extent of variation in practices, whether clinician-related factors and local structural factors affect variation, and the economic consequences of varying practices. Materials and methods: Questionnaire studies with 19 or 16 hypothetical patient cases were conducted among 165 primary health care (PHC) physicians, 356 occupational health care (OHC) physicians, 338 surgeons and 1132 dentists. Results: The difference between the lowest and the highest number of sick leave days prescribed for the 19 patient cases was almost four-fold in PHC physicians and surgeons and eight-fold in OHC physicians, which represents a societal cost of tens of thousands of euros. Some dentists did not prescribe sick leave to any of the 16 patient cases, and some prescribed nearly a hundred days altogether. The overall number of sick leave days OHC physicians prescribed was smaller than in PHC physicians. More days of sick leave were prescribed by those working in smaller municipalities than larger population centres. Conclusion: There was considerable variation in the sick leave prescribing practices of Finnish health care professionals. This means that patients may not receive equal social benefits. Sick leave carries considerable economic consequences, and unifying prescribing practices could bring significant cost savings to society.

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Juvenile hormone (JH) exerts pleiotropic functions during insect life cycles. The regulation of JH biosynthesis by neuropeptides and biogenic amines, as well as the transport of JH by specific binding proteins is now well understood. In contrast, comprehending its mode of action on target organs is still hampered by the difficulties in isolating specific receptors. In concert with ecdysteroids, JH orchestrates molting and metamorphosis, and its modulatory function in molting processes has gained it the attribute "status quo" hormone. Whereas the metamorphic role of JH appears to have been widely conserved, its role in reproduction has been subject to many modifications. In many species, JH stimulates vitellogenin synthesis and uptake. In mosquitoes, however, this function has been transferred to ecdysteroids, and JH primes the ecdysteroid response of developing follicles. As reproduction includes a variety of specific behaviors, including migration and diapause, JH has come to function as a master regulator in insect reproduction. The peak of pleiotropy was definitely reached in insects exhibiting facultative polymorphisms. In wing-dimorphic crickets, differential activation of JH esterase determines wing length. The evolution of sociality in Isoptera and Hymenoptera has also extensively relied on JH. In primitively social wasps and bumble bees, JH integrates dominance position with reproductive status. In highly social insects, such as the honey bee, JH has lost its gonadotropic role and now regulates division of labor in the worker caste. Its metamorphic role has been extensively explored in the morphological differentiation of queens and workers, and in the generation of worker polymorphism, such as observed in ants.