974 resultados para Building structures


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This paper presents a procedure that allows us to determine the preference structures(PS) associated to each of the different groups of actors that can be identified in a groupdecision making problem with a large number of individuals. To that end, it makesuse of the Analytic Hierarchy Process (AHP) (Saaty, 1980) as the technique to solvediscrete multicriteria decision making problems. This technique permits the resolutionof multicriteria, multienvironment and multiactor problems in which subjective aspectsand uncertainty have been incorporated into the model, constructing ratio scales correspondingto the priorities relative to the elements being compared, normalised in adistributive manner (wi = 1). On the basis of the individuals’ priorities we identifydifferent clusters for the decision makers and, for each of these, the associated preferencestructure using, to that end, tools analogous to those of Multidimensional Scaling.The resulting PS will be employed to extract knowledge for the subsequent negotiationprocesses and, should it be necessary, to determine the relative importance of thealternatives being compared using anyone of the existing procedures

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Salvage logging is a common practice carried out in burned forests worldwide, and intended to mitigate the economic losses caused by wildfires. Logging implies an additional disturbance occurring shortly after fire, although its ecological effects can be somewhat mitigated by leaving wood debris on site. The composition of the bird community and its capacity to provide ecosystem services such as seed dispersal offleshy-fruited plants have been shown to be affected by postfire logging. We assessedthe effects of the habitat structure resulting from different postfire management practices on the bird community, in three burned pine forests in Catalonia (western Mediterranean). For this purpose, we focused on the group of species that is responsible for seed dispersal, a process which takes place primarily during the winter in theMediterranean basin. In addition, we assessed microhabitat selection by seed disperser birds in such environments in relation to management practices. Our results showed a significant, positive relationship between the density of wood debris piles and the abundance of seed disperser birds. Furthermore, such piles were the preferredmicrohabitat of these species. This reveals an important effect of forest management on seed disperser birds, which is likely to affect the dynamics of bird-dependent seed dispersal. Thus, building wood debris piles can be a useful practice for the conservation of both the species and their ecosystem services, while also being compatible with timber harvesting

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[spa]Este artículo analiza las estructuras sociales subyacentes a la Revolución haitiana, y cómo las aspiraciones diferentes de negros y mulatos durante la Revolución de independencia (1791-1804) se trasladaron al período postabolición. Pese a los cambios en la legislación agraria después de la independencia, el fracaso a la hora de proporcionar unas condiciones de trabajo adaptadas a las demandas de los trabajadores rurales haitianos se añadió a las dificultades y los obstáculos enfrentados por Haití en su intento por construir una nación próspera y en libertad

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Engineering and pricing of large recovery boiler were studied in this work. Engineering was carried out with Anita 4.2 which is an engineering program of Andritz. Key initial values were chosen with previous studies. Primary target of this work was to find out the consequences that furnace dimensions and furnace screen vertical part has to boiler pricing. Boilers that were engineered had different rate of furnace width and depth and different heat transfer plate count. Boiler balances were invariable. Boilers with different vertical screen construction were also calculated. First variation was boiler with vertical screen up to furnace roof. Other variation was to connect vertical screen to Pre-boiler generating bank inlet tubes. Total prices were calculated to engineered boilers. Pricing was sort out to heat transfers, high pressure pipes, steel structures, auxiliary equipments and civil/structural costs. This study did not notice parts of the boiler which costs do not vary with the construction of the boiler. Heat transfers had the largest share of costs. Boiler building had the most significant differences between the boilers. Furnace screen had also significant role especially to costs of the boiler building.

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Implantation of deep brain stimulation (DBS) electrodes via stereotactic neurosurgery has become a standard procedure for the treatment of Parkinson's disease. More recently, the range of neuropsychiatric conditions and the possible target structures suitable for DBS have greatly increased. The former include obsessive compulsive disease, depression, obesity, tremor, dystonia, Tourette's syndrome and cluster-headache. In this article we argue that several of the target structures for DBS (nucleus accumbens, posterior inferior hypothalamus, nucleus subthalamicus, nuclei in the thalamus, globus pallidus internus, nucleus pedunculopontinus) are located at strategic positions within brain circuits related to motivational behaviors, learning, and motor regulation. Recording from DBS electrodes either during the operation or post-operatively from externalized leads while the patient is performing cognitive tasks tapping the functions of the respective circuits provides a new window on the brain mechanisms underlying these functions. This is exemplified by a study of a patient suffering from obsessive-compulsive disease from whom we recorded in a flanker task designed to assess action monitoring processes while he received a DBS electrode in the right nucleus accumbens. Clear error-related modulations were obtained from the target structure, demonstrating a role of the nucleus accumbens in action monitoring. Based on recent conceptualizations of several different functional loops and on neuroimaging results we suggest further lines of research using this new window on brain functions.

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A novel unsymmetric dinucleating ligand (LN3N4) combining a tridentate and a tetradentate binding sites linked through a m-xylyl spacer was synthesized as ligand scaffold for preparing homo- and dimetallic complexes, where the two metal ions are bound in two different coordination environments. Site-selective binding of different metal ions is demonstrated. LN3N4 is able to discriminate between CuI and a complementary metal (M′ = CuI, ZnII, FeII, CuII, or GaIII) so that pure heterodimetallic complexes with a general formula [CuIM′(LN3N4)]n+ are synthesized. Reaction of the dicopper(I) complex [CuI 2(LN3N4)]2+ with O2 leads to the formation of two different copper-dioxygen (Cu2O2) intermolecular species (O and TP) between two copper atoms located in the same site from different complex molecules. Taking advantage of this feature, reaction of the heterodimetallic complexes [CuM′(LN3N4)]n+ with O2 at low temperature is used as a tool to determine the final position of the CuI center in the system because only one of the two Cu2O2 species is formed

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Postprint (author’s final draft)

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Crystalline structures of zeolites can be studied using different representations: the internal symmetry obtained by X-Ray or neutron diffraction crystallography techniques or a systematic analysis of the basic structural units which can be arranged to build the geometries of each kind of zeolite. In this work the basic concepts of three building units, SBU (Secondary Building Units), SSU (Structural SubUnits) and PBU (Periodic Building Units) are presented. The properties of the resulting crystalline structures are discussed (pores, cavities, channels), describing the influence of each one of these properties in processes of physical-chemical interest. Representative case studies of known zeolite crystalline structures are also discussed in terms of their space group classification.

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Appearance of trust in regional, co-operative networks In our times, the value of social networks has been widely acknowledged. One can say that it is important for private persons to get networked, whilst it is even a must for companies and organizations in business life. This doctor's thesis examines three co-operative regional networks. Networks are located in Western Uusimaa (Länsi-Uusimaa) region in southernmost Finland, and they had both public organizations and private companies as participants (later called ‘players’). Initially, all of them were co-financed from public funds, and two of them are still operational while writing this. The main target of these networks has been to act as learning networks. The learning network stands for an ensemble of research and development units and workplaces constituting a common forum for learning. The main focus in this study has been on qualitative and structural characteristics of the networks, and how they are relating with intrinsic trust. In addition to the development of trust, it has been studied, at what level organizational learning within the networks takes place, and lastly, what kind of factors facilitate the development of social capital. The theoretical framework for the study is built on analysing trust and social capital. It is a 'mission impossible' to find single definitions for such major concepts. In this study, from the research questions' point of view it has been more relevant to concentrate on the aspects of networking and the relationships between the participating organizations. The total view in this study is very network-centric, and therefore those theories which have similar point of view have been prioritized. Such is the theory about structural holes by Ronald S. Burt (1992). It has been widely applied; especially his views on constraints affecting players in networks. The purpose of this study has not been to create new theories or to analyse and compare thoroughly the existing theoretical trends. Instead, the existing theories have provided the study with conceptual tools, which have been utilized for supporting the empirical results. The aim has been to create an explanatory case study consisting relevant discussion on the relationship between the network characteristics and the appearance of trust. The conceptual categorization for confidence vs. trust created by Niklas Luhmann (1979) is another important theoretical building block. In most cases, co-operation in networks is initiated by people already trusting in each other and willing to work together. However, personal trust is not sufficient in the long run to sustain the co-operation within the network: more abstract systemic trust described by Luhmann must also emerge. In the networks with different structures and at different development phases, these forms of trust appear at different levels. In this study, Luhmann’s systemic trust as a term has been replaced by the concept of 'trust in network as a system'. Structural characteristics of a network (density, centrality, structural holes etc.) have been selected to explain the creation of social capital and trust. The ability to adapt new information is essential for the development of social capital. Qualitative analysis for development phase has been used, and the Learning Network Maturity Test by Leenamaija Otala (2000) and her work have been applied. Thus, the qualitative characteristics and the structural characteristics of the networks are utilized together, when the creation of social capital and appearance of trust are assessed. Social Network Analysis, questionnaires and interviews have been the research methods. Quantitative and qualitative data have been combined. There is a similarity in viewpoints to research data with Extensive Case Study method, in which different cases are searched by exploring various cases and comparing certain common features between them and generic models. Development of trust, social capital and organizational learning has been explained in the study by comparing the networks in hand. Being a case study, it doesn't have targets to provide with general results and findings like conventional surveys. However, in this work phenomena and mechanisms related to them are interpreted from the empirical data. Key finding of this study is that the networks with high structural equality and clear target setting enable building trust to the network as a system. When systemic trust is present, e.g. changes in personnel involved in the co-operation won't hinder the network from remaining operational. On the other hand, if the players are not well motivated to co-operate, if the network is extremely centralized structurally, or if the network has players holding very much more beneficial position compared to the others, systemic trust won't develop: trust tends to remain at the personal level, and is directed to some players only. Such networks won't generate results and benefits to its players, and most probably they won’t live very long. In other words, learning networks cannot solely be based on willingness to learn, but also on willingness to co-operate.

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This Master's thesis is devoted to semiconductor samples study using time-resolved photoluminescence. This method allows investigating recombination in semiconductor samples in order to develop quality of optoelectronic device. An additional goal was the method accommodation for low-energy-gap materials. The first chapter gives a brief intercourse into the basis of semiconductor physics. The key features of the investigated structures are noted. The usage area of the results covers saturable semiconductor absorber mirrors, disk lasers and vertical-external-cavity surface-emittinglasers. The experiment set-up is described in the second chapter. It is based on up-conversion procedure using a nonlinear crystal and involving the photoluminescent emission and the gate pulses. The limitation of the method was estimated. The first series of studied samples were grown at various temperatures and they suffered rapid thermal annealing. Further, a latticematched and metamorphically grown samples were compared. Time-resolved photoluminescence method was adapted for wavelengths up to 1.5 µm. The results allowed to specify the optimal substrate temperature for MBE process. It was found that the lattice-matched sample and the metamorphically grown sample had similar characteristics.

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The crystal and molecular structures of [bis(5-chloro-2-methoxybenzoate)tetraaquamanganese(II)], [pentaaqua(5-chloro-2-methoxybenzoato)cobalt(II)] (5-chloro-2-methoxybenzoate), [pentaaqua(5-chloro-2-methoxybenzoato)nickel(II)] (5-chloro-2-methoxybenzoate) and [aquabis(5-chloro-2-methoxybenzoate)zinc(II)] monohydrate were determined by a single-crystal X-ray analysis. Mn(H2O)4L2 (where L = C8H6ClO3) crystallizes in the monoclinic system, space group P21/c. [Co(H2O)5L]L and [Ni(H2O)5L]L both are isostructural, space group P212121. The crystals of [Zn(H2O)L2] H2O are monoclinic, space group Pc. Mn(II) ion is positioned at the crystallographic symmetry center. Mn(II) and Co(II) ions adopt the distorted octahedral coordination but Zn(II) tetrahedral one.The carboxylate groups in the complexes with M(II) cations function as monodentate, bidentate and/or free COO-groups. The ligands exist in the crystals as aquaanions. The complexes of 5-chloro-2-methoxybenzoates with Mn(II), Co(II) and Zn(II) form bilayer structure.

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The aim of this thesis was to study network structures and modularity among biofuel heating system manufacturers in the Finnish bioenergy sector by utilizing the perspectives of numerous Finnish bioenergy specialists. The study is qualitative due to the fact that the research material was gathered with semi-structured theme interviews during May and June 2010. The research methodology used in the thesis combines conceptual and action-oriented approach. Networks, value nets, and modularity were studied from different perspectives. Three network and platform strategies were discovered and a general network structure was formed. Moreover, benefits and disadvantages of networks and modularity among biofuel heating system manufacturers were illustrated. The analysis provides a comprehensive perception of the industry. The results of the research were constructed by implementing existing theories into practice. Also future recommendations for the biofuel heating system manufacturers were given. The results can be considered to be beneficial because the number of previous studies about the subject is relatively small. The reliability of the study is eminent because the number of the interviews was inclusive.

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In the construction industry, the role of project management and monitoring is emphasized, because the responsibilities have been carefully planned and divided. A concrete element factory manufactures the units based on construction drawings, while a transport company is responsible of transporting the elements to the worksite. At the worksite, an installation team assembles the elements according to plans. Usually, there are several manufacturers and transport companies involved in the construction process and the distances between different parties can be rather long. Therefore, the role of information exchange is critical in order to control, for example, schedules and exceptions. From the viewpoint of project management, the whole process should be controlled and monitored in realtime - in such a way that the managers are able to analyze and report the data afterwards. In this master’s thesis, a mobile-aided construction project monitoring system is designed and implemented. The monitoring system consists of three main components: mobile phone application, server software and an interface application to Tekla Structures BIM-software. Precast construction components, projects and users are identified by using 2D-barcodes that are read with the camera of a mobile phone. An option would be to use RFID tags and readers. After successful identification, the precast component can be tagged with monitoring data, including state acknowledgments and error reports that are sent and saved to the server. Collected data can be viewed through the www-pages of the monitoring system. In addition, the data can be synchronized to the Tekla Structures-software that is running the 3D-model of the whole building. Synchronization maintains and enhances the traceability of monitoring data, as well as, helps to visualize the progression of the project.

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Nykypäivänä energiansäästötavoitteet ovat haasteena yhä useammalle energiankuluttajalle. Tavoitteisiin päästäkseen yritykset ja kunnalliset energiankuluttajat kaipaavat usein apua kannattavien energiansäätökeinojen löytämiseksi. Erilaiset energiakatselmukset vastaavat tähän tarpeeseen ja ovat esimerkki tuloksellisesta energiansäästöstä. Lappeenrannan teknillinen yliopisto on tutkinut energiatehokkuutta pitkään erilaisissa projekteissa teollisuuden kanssa yhteistyössä. Osa LUT:n energiatehokkuustutkimusta ovat energia-auditoinnit yrityksille ja kunnille, joita LUT Energian projektin puitteissa alettiin kehittää vuoden 2008 syksyllä. Energia-auditointien fokuksena on pyritty pitämään pumppausprosessien energiatehokkuuden optimointia, sillä aihetta on tutkittu yliopistolla laajasti. Pumppausprosesseissa on todettu olevan merkittävä energiansäästöpotentiaali: pumppauksen kuluttamasta energiasta voi olla mahdollista säästää jopa 50 % erilaisilla laite- ja säästötaparatkaisuilla. Pumppausprosessien energia-auditointeja on tehty teollisuuden pumppauskohteisiin kuin myös kunnallisiin vesi-huoltolaitoksiin. Lisäksi energia-auditointien puitteissa on tutkittu energiansäästömahdollisuuksia rakennuksissa. Energiansäästökohteita etsitään sekä lämpö- että sähköenergian osalta. Energia-auditoinneissa pumppausten osalta energiansäästöpotentiaalia on todettu olevan etenkin suuren kokoluokan pumpuissa, joilla on pitkä vuosittainen käyttöaika. Myös pumppujen säätötavalla on suuri merkitys energiankulutukseen. Rakennusten osalta on pyritty selvittämään, kuinka energiankulutus jakautuu eri kulutusryhmien kesken. Säästökohteita on löydetty muun muassa rakennusten tiiviydestä, ilmanvaihdosta kuin valaistuksestakin. Monia auditointien asiakkaita on kiinnostanut etenkin led-teknologian hyödyntäminen yleisvalaistuksessa sekä muut keinot säästää valaistuksen energiankulutuksessa. Pyrkimyksenä on kehittää energia-auditointeja projektin aikana saavutettujen kokemusten avulla sekä myös liiketaloudellisessa mielessä opinnäytetutkielmien avulla. Menestyksekäs palveluliiketoiminta edellyttää määriteltyjä toimintatapoja, riittävän tarkkaa palvelujen rajausta ja koko energia-auditointiprosessin kehittämistä aina asiakassuhteen luomisesta sen jatko-hoitoon saakka.