995 resultados para Series solutions


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Although classic bankruptcy problems take into account a single claims vector, Pulido et al. (2008) show that there are real bankruptcy situations where agents face more than one reference vector. In particular, they consider the claims and an additional reference vector. To analyze these situations, they propose the extreme and the diagonal approaches. Nonetheless, the former approach depends on the order of the vectors: if we interchange the claims and the reference vectors, the result changes. Moreover their study is limited to the case in which the reference vector is lower than the claims vector. In the present note, we propose an extension that solves these short- comings by introducing the idea of impartiality. Keywords: bankruptcy problems; reference point; compromise solution; impartiality.

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Background:Microcystic macular edema can occur after optic neuropathies of various etiologies, and is easily demonstrated by OCT. We report a cohort of patients with microcystic macular edema. Patients and Methods: All patients with optic neuropathy and microcystic macular edema were enrolled. Demographics, visual function, retinal angiographies and OCT parameters were studied. Results: Nineteen patients (23 eyes) exhibited microcystic macular edema: 10 men/9 women, aged 17-91 years. Etiologies of optic nerve atrophy were compressive (5), inflammatory (4), glaucoma (3), ischemic (3), trauma (2), degenerative (1), and hereditary (1). Median visual acuity was 4/10 (NLP-12/10). Fluorescein angiography showed no leakage. Topography of the microcystic macular edema correlated with near infrared images but with visual field defects in only 26 %. OCT parameters were all abnormal. Conclusions: Microcystic macular edema is a non-specific manifestation from an optic neuropathy of any etiology. The precise mechanism leading to microcystic macular edema remains unknown but trans-synaptic retrograde degeneration with Müller cells dysfunction is likely.

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La fabrication, la distribution et l'usage de fausses pièces d'identité constituent une menace pour la sécurité autant publique que privée. Ces faux documents représentent en effet un catalyseur pour une multitude de formes de criminalité, des plus anodines aux formes les plus graves et organisées. La dimension, la complexité, la faible visibilité, ainsi que les caractères répétitif et évolutif de la fraude aux documents d'identité appellent des réponses nouvelles qui vont au-delà d'une approche traditionnelle au cas par cas ou de la stratégie du tout technologique dont la perspective historique révèle l'échec. Ces nouvelles réponses passent par un renforcement de la capacité de comprendre les problèmes criminels que posent la fraude aux documents d'identité et les phénomènes qui l'animent. Cette compréhension est tout bonnement nécessaire pour permettre d'imaginer, d'évaluer et de décider les solutions et mesures les plus appropriées. Elle requière de développer les capacités d'analyse et la fonction de renseignement criminel qui fondent en particulier les modèles d'action de sécurité les plus récents, tels que l'intelligence-led policing ou le problem-oriented policing par exemple. Dans ce contexte, le travail doctoral adopte une position originale en postulant que les fausses pièces d'identité se conçoivent utilement comme la trace matérielle ou le vestige résultant de l'activité de fabrication ou d'altération d'un document d'identité menée par les faussaires. Sur la base de ce postulat fondamental, il est avancé que l'exploitation scientifique, méthodique et systématique de ces traces au travers d'un processus de renseignement forensique permet de générer des connaissances phénoménologiques sur les formes de criminalité qui fabriquent, diffusent ou utilisent les fausses pièces d'identité, connaissances qui s'intègrent et se mettent avantageusement au service du renseignement criminel. A l'appui de l'épreuve de cette thèse de départ et de l'étude plus générale du renseignement forensique, le travail doctoral propose des définitions et des modèles. Il décrit des nouvelles méthodes de profilage et initie la constitution d'un catalogue de formes d'analyses. Il recourt également à des expérimentations et des études de cas. Les résultats obtenus démontrent que le traitement systématique de la donnée forensique apporte une contribution utile et pertinente pour le renseignement criminel stratégique, opérationnel et tactique, ou encore la criminologie. Combiné aux informations disponibles par ailleurs, le renseignement forensique produit est susceptible de soutenir l'action de sécurité dans ses dimensions répressive, proactive, préventive et de contrôle. En particulier, les méthodes de profilage des fausses pièces d'identité proposées permettent de révéler des tendances au travers de jeux de données étendus, d'analyser des modus operandi ou d'inférer une communauté ou différence de source. Ces méthodes appuient des moyens de détection et de suivi des séries, des problèmes et des phénomènes criminels qui s'intègrent dans le cadre de la veille opérationnelle. Ils permettent de regrouper par problèmes les cas isolés, de mettre en évidence les formes organisées de criminalité qui méritent le plus d'attention, ou de produire des connaissances robustes et inédites qui offrent une perception plus profonde de la criminalité. Le travail discute également les difficultés associées à la gestion de données et d'informations propres à différents niveaux de généralité, ou les difficultés relatives à l'implémentation du processus de renseignement forensique dans la pratique. Ce travail doctoral porte en premier lieu sur les fausses pièces d'identité et leur traitement par les protagonistes de l'action de sécurité. Au travers d'une démarche inductive, il procède également à une généralisation qui souligne que les observations ci-dessus ne valent pas uniquement pour le traitement systématique des fausses pièces d'identité, mais pour celui de tout type de trace dès lors qu'un profil en est extrait. Il ressort de ces travaux une définition et une compréhension plus transversales de la notion et de la fonction de renseignement forensique. The production, distribution and use of false identity documents constitute a threat to both public and private security. Fraudulent documents are a catalyser for a multitude of crimes, from the most trivial to the most serious and organised forms. The dimension, complexity, low visibility as well as the repetitive and evolving character of the production and use of false identity documents call for new solutions that go beyond the traditional case-by-case approach, or the technology-focused strategy whose failure is revealed by the historic perspective. These new solutions require to strengthen the ability to understand crime phenomena and crime problems posed by false identity documents. Such an understanding is pivotal in order to be able to imagine, evaluate and decide on the most appropriate measures and responses. Therefore, analysis capacities and crime intelligence functions, which found the most recent policing models such as intelligence-led policing or problem-oriented policing for instance, have to be developed. In this context, the doctoral research work adopts an original position by postulating that false identity documents can be usefully perceived as the material remnant resulting from the criminal activity undertook by forgers, namely the manufacture or the modification of identity documents. Based on this fundamental postulate, it is proposed that a scientific, methodical and systematic processing of these traces through a forensic intelligence approach can generate phenomenological knowledge on the forms of crime that produce, distribute and use false identity documents. Such knowledge should integrate and serve advantageously crime intelligence efforts. In support of this original thesis and of a more general study of forensic intelligence, the doctoral work proposes definitions and models. It describes new profiling methods and initiates the construction of a catalogue of analysis forms. It also leverages experimentations and case studies. Results demonstrate that the systematic processing of forensic data usefully and relevantly contributes to strategic, tactical and operational crime intelligence, and also to criminology. Combined with alternative information available, forensic intelligence may support policing in its repressive, proactive, preventive and control activities. In particular, the proposed profiling methods enable to reveal trends among extended datasets, to analyse modus operandi, or to infer that false identity documents have a common or different source. These methods support the detection and follow-up of crime series, crime problems and phenomena and therefore contribute to crime monitoring efforts. They enable to link and regroup by problems cases that were previously viewed as isolated, to highlight organised forms of crime which deserve greatest attention, and to elicit robust and novel knowledge offering a deeper perception of crime. The doctoral research work discusses also difficulties associated with the management of data and information relating to different levels of generality, or difficulties associated with the implementation in practice of the forensic intelligence process. The doctoral work focuses primarily on false identity documents and their treatment by policing stakeholders. However, through an inductive process, it makes a generalisation which underlines that observations do not only apply to false identity documents but to any kind of trace as soon as a profile is extracted. A more transversal definition and understanding of the concept and function of forensic intelligence therefore derives from the doctoral work.

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El presente trabajo pretende la caracterización de la distribución espacial típica del cultivo de arroz en regadíos del valle del Ebro, donde la presencia del cultivo está ligada a la existencia de suelos salino-sódicos. Esta caracterización ha de permitir identificar las áreas donde es típica la presencia del cultivo año tras año y las áreas donde es frecuente su fluctuación debido tanto a condiciones variables de salinidad del suelo como a variabilidad en las condiciones de mercado. Para ello se ha recurrido al análisis de una serie temporal de mapas de cultivos (7 años) derivados de la clasificación supervisada de imágenes Landsat TM. La determinación de las áreas típicas y de fluctuación del cultivo de arroz se hace entonces a partir del análisis estadístico de clases, y mediante superposición espacial de coberturas en un entorno SIG-Raster.

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Sudoku problems are some of the most known and enjoyed pastimes, with a never diminishing popularity, but, for the last few years those problems have gone from an entertainment to an interesting research area, a twofold interesting area, in fact. On the one side Sudoku problems, being a variant of Gerechte Designs and Latin Squares, are being actively used for experimental design, as in [8, 44, 39, 9]. On the other hand, Sudoku problems, as simple as they seem, are really hard structured combinatorial search problems, and thanks to their characteristics and behavior, they can be used as benchmark problems for refining and testing solving algorithms and approaches. Also, thanks to their high inner structure, their study can contribute more than studies of random problems to our goal of solving real-world problems and applications and understanding problem characteristics that make them hard to solve. In this work we use two techniques for solving and modeling Sudoku problems, namely, Constraint Satisfaction Problem (CSP) and Satisfiability Problem (SAT) approaches. To this effect we define the Generalized Sudoku Problem (GSP), where regions can be of rectangular shape, problems can be of any order, and solution existence is not guaranteed. With respect to the worst-case complexity, we prove that GSP with block regions of m rows and n columns with m = n is NP-complete. For studying the empirical hardness of GSP, we define a series of instance generators, that differ in the balancing level they guarantee between the constraints of the problem, by finely controlling how the holes are distributed in the cells of the GSP. Experimentally, we show that the more balanced are the constraints, the higher the complexity of solving the GSP instances, and that GSP is harder than the Quasigroup Completion Problem (QCP), a problem generalized by GSP. Finally, we provide a study of the correlation between backbone variables – variables with the same value in all the solutions of an instance– and hardness of GSP.

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A method for dealing with monotonicity constraints in optimal control problems is used to generalize some results in the context of monopoly theory, also extending the generalization to a large family of principal-agent programs. Our main conclusion is that many results on diverse economic topics, achieved under assumptions of continuity and piecewise differentiability in connection with the endogenous variables of the problem, still remain valid after replacing such assumptions by two minimal requirements.

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The present paper is devoted to the results of experimental research undertaken into photocatalytical oxidation (PCO) of aqueous solutions of de-icing agents and aqueous extract of jet fuel. The report consists of introduction, literature review, description of materials and methods, discussion of results and conclusions. TiO2 was selected as a photocatalyst for the experiments with synthetic solutions of ethylene glycol, 2-ethoxyethanol and aqueous extract of jet fuel. To explain the PCO mechanisms affecting certain behaviour of de-icing agent under distinctive conditions, the following factors were studied: the impact of initial concentration of pollutant, the role of pH, the presence of tert-butanol as OH·-radicals scavenger and mineral admixtures. PCO under solar radiation performed in two ways: catalysed by irradiated TiO2 slurry or by TiO2 attached to buoyant hollow glass micro-spheres. Special attention was paid to the energy-saving PCO with reduced intensity mixing of the slurry. The effect of PCO was assessed by determination of residual chemical oxygen demand of solution (COD) and by measuring of concentration of glycols. The PCO process efficiency was assumed to be dependent on the TiO2 suspension fractional composition. Thus, the following effects of solutions’ media were viewed: presence of organic admixtures, pH influence, mixing mode during the PCO. The effects of mineral admixtures - Ca2+, Fe3+/2+, Mn2+, SO42- - that are often present in natural and wastewater systems or produced during the degradation of organic pollutants and which can affect the rate of PCO of de-icing agents, were also investigated.

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Tämä diplomityö tutkii turvallisia etäyhteystapoja yritysverkkoihin. Samanaikasesti kuin Internettiin liitetyt langattomat verkot, kuten langattomat lähiverkot ja pakettikytkentäiset matkapuhelinverkot, tulevat yhä yleisemmiksi, mahdollisuus etäyhteksien luomiseen näiden verkkojen kautta tulee yhä suositummaksi. Vaikka tietoverkot kehittyvät, pysyvät niitä uhkaavat yleisluontoiset uhat samoina. IP pohjaiset VPN-verkot ovat sopiva tapa suojata Internetin ylitse tapahtuvia etäyhteksiä. Eri VPN-ratkaisuja on kuitenkin tarjolla laaja valikoima. Oikean tyyppisen VPN-ratkaisun valinta on kriittistä, jotta yrityksen etäyhteystarpeet saadaan täytettyä. Diplomityö esittelee eräänä vaihtoehtona miten Pocket PC 2002 PDA laitetta ja Windows XP Professional käyttöjärjestelmää voidaan käyttää edullisen VPN ratkaisun toteuttamiseen.

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Logistiikkapalveluiden markkinat ovat viime vuosina muuttuneet. Kilpailtu toimiala ja asiakasvaatimusten muuttuminen ovat pakottaneet yritykset pyrkimään entistä tehokkaampaan jakeluketjuun. Työn tarkoituksena oli tutkia sähköisten asiakasliittymien toimivuutta asiakkaan näkökulmasta Euro Express tuotannossa ja prosessissa. Tarkoituksena oli selvittää eri sidosryhmien vaatimukset prosessille huomioiden sähköisen liiketoiminnan tuomat edut ja ominaispiirteet. Tavoitteena oli kuvata olemassa oleva prosessi ja tutkia prosessin rajapinnat –asiakas, tuotanto ja ulkoiset sidosryhmät. Tutkielmassa sähköisten ratkaisujen ominaispiirteet on käyty läpi ja tulevaisuuden kehitysnäkökulmista keskusteltu. Kehittyneiden tietoteknisten ratkaisujen avulla jatkuva prosessien uudistaminen (Business Process Reengineering) on mahdollista. Yleisesti epäolennaisuudet asiakasrajapinnassa, informaation kulussa ja yhteyksissä eri järjestelmien välillä aiheuttavat ongelmia sähköisten ratkaisujen toteuttamisessa. Tulevaisuudessa logistiikka yritykset ottavat entistä enemmän käyttöönsä uudenaikaisia teknologisia ratkaisuja tilaukseen, tuotantoon ja asiakaspalveluun. Näiden uudenlaisten ratkaisujen kehittämisestä on hyötyä sekä käyttäjälle että tarjoajalle, mutta ne ovat myös pakollisia palveluntarjoajalle kehittyäkseen markkinoilla. Tulevaisuudessa kilpailun tiivistyessä ja asiakkaiden vaatimusten kasvaessa on kiinnitettävä entistä suurempaa huomiota koko prosessiketjun toimivuuteen. Uudet teknologiset ratkaisut ja niiden käyttäminen tehokkaasti tuovat yrityksille kilpailuetuja, joita ei muuten olisi saavutettavissa.

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Tutkielman tavoitteena oli suunitella markkina-analyysi ja sitä käyttäen määritellä Danzasin Solutions liiketoimintayksikön mahdollisuuksia laajentaa toimintaansa Suomen terveydenhuolto/ lääke- ja elektroniikka/ telekommunikaatiosektoreilla. Danzas Solutions toimisi logistiikkaintegraattorina toimittamalla kokonaisvaltaisia logistisia ratkaisuja. Tutkimus tehtiin haastattelemalla neljää Danzasin asiakasta. Mahdollisimman laajan ja yleistettävän tuloksen saamiseksi haastateltavat valitiin logistiikan ulkoistamisasteeltaan vaihteleviksi. Tutkimus tehtiin ensin tutkimalla sekundääristä informaatiota markkinoilta ja täydentämällä sitä haastatteluista saadulla kvalitatiivisella primääri informaatiolla ja case yrityksen sisäisellä analyysillä. Painopiste tutkimuksessa oli selvittää yritysten ulkoistamiseen ja logistiikkakumppanin valintaan vaikuttavia kriteereitä. Logistiikkaintegraattorille suurimmat mahdollisuudet löytyvät elektroniikka/ telekommunikaatiosektorilta. Logistiikka tällä sektorilla on vaativaa ja yrityksillä ei ole resursseja hallita sitä itse. Terveydenhuolto/ lääkesektorilla yrityksillä on yleensä muut keinot jakeluketjun hallintaan ja ne eivät tarvitse logistiikkaintegraattorin palveluita.

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In his version of the theory of multicomponent systems, Friedman used the analogy which exists between the virial expansion for the osmotic pressure obtained from the McMillan-Mayer (MM) theory of solutions in the grand canonical ensemble and the virial expansion for the pressure of a real gas. For the calculation of the thermodynamic properties of the solution, Friedman proposed a definition for the"excess free energy" that is a reminder of the ancient idea for the"osmotic work". However, the precise meaning to be attached to his free energy is, within other reasons, not well defined because in osmotic equilibrium the solution is not a closed system and for a given process the total amount of solvent in the solution varies. In this paper, an analysis based on thermodynamics is presented in order to obtain the exact and precise definition for Friedman"s excess free energy and its use in the comparison with the experimental data.

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BACKGROUND AND PURPOSE: There are few data on long-term clinical results and tolerance of brachytherapy in anal canal cancer. We present one of the largest retrospective analyses of anal canal cancers treated with external beam radiotherapy with/without (±) chemotherapy followed by a brachytherapy boost. MATERIALS AND METHODS: We performed a retrospective analysis of clinical results in terms of efficacy and toxicity. The impact of different clinical and therapeutic variables on these outcomes was studied. RESULTS: From May 1992 to December 2009, 209 patients received brachytherapy after external beam radiotherapy ± chemotherapy. Of these patients, 163 were stage II or stage IIIA (UICC 2002) and 58 were N1-3. According to age, ECOG performance status (PS), and comorbidities, patients received either radiotherapy alone (58/209) or radiochemotherapy (151/209). The median follow-up was 72.8 months. The 5- and 10-year local control rates were 78.6 and 73.9 %, respectively. Globally, severe acute and late G3-4 reactions (NCI-CTC scale v. 4.0) occurred in 11.2 and 6.3 % of patients, respectively. Univariate analysis showed the statistical impact of the pelvic treatment volume (p = 0.046) and of the total dose (p = 0.02) on the risk of severe acute and late toxicities, respectively. Only six patients required permanent colostomy because of severe late anorectal toxicities. CONCLUSION: After a long follow-up time, brachytherapy showed an acceptable toxicity profile and high local control rates in patients with anal canal cancer.