486 resultados para swing conveyor


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The Arctic Ocean System is a key player regarding the climatic changes of Earth. Its highly sensitive ice Cover, the exchange of surface and deep water masses with the global ocean and the coupling with the atmosphere interact directly with global climatic changes. The output of cold, polar water and sea ice influences the production of deep water in the North Atlantic and controls the global ocean circulation ("the conveyor belt"). The Arctic Ocean is surrounded by the large Northern Hemisphere ice sheets which not only affect the sedimentation in the Arctic Ocean but also are supposed to induce the Course of glacials and interglacials. Terrigenous sediment delivered from the ice sheets by icebergs and meltwater as well as through sea ice are major components of Arctic Ocean sediments. Hence, the terrigenous content of Arctic Ocean sediments is an outstanding archive to investigate changes in the paleoenvironment. Glazigenic sediments of the Canadian Arctic Archipelago and surface samples of the Arctic Ocean and the Siberian shelf regions were investigated by means of x-ray diffraction of the bulk fraction. The source regions of distinct mineral compositions were to be deciphered. Regarding the complex circumpolar geology stable christalline shield rocks, active and ancient fold belts including magmatic and metamorphic rocks, sedimentary rocks and wide periglacial lowlands with permafrost provide a complete range of possible mineral combinations. Non- glaciated shelf regions mix the local input from a possible point source of a particular mineral combination with the whole shelf material and function as a sampler of the entire region draining to the shelf. To take this into account, a literature research was performed. Descriptions of outcropping lithologies and Arctic Ocean sediments were scanned for their mineral association. The analyses of glazigenic and shelf sediments yielded a close relationship between their mineral composition and the adjacent source region. The most striking difference between the circumpolar source regions is the extensive outcrop of carbonate rocks in the vicinity of the Canadian Arctic Archipelago and in N Greenland while siliciclastic sediments dominate the Siberian shelves. In the Siberian shelf region the eastern Kara Sea and the western Laptev Sea form a destinct region defined by high smectite, (clino-) pyroxene and plagioclase input. The source of this signal are the extensive outcrops of the Siberian trap basalt in the Putorana Plateau which is drained by the tributaries of the Yenissei and Khatanga. The eastern Laptev Sea and the East Siberian Sea can also be treated as one source region containing a feldspar, quartz, illite, mica, and chlorite asscciation combined with the trace minerals hornblende and epidote. Franz Josef Land provides a mineral composition rich in quartz and kaolinite. The diverse rock suite of the Svalbard archipelago distributes specific mineral compositions of highly metamorphic christalline rocks, dolomite-rich carbonate rocks and sedimentary rocks with a higher diagenetic potential manifested in stable newly built diagenetic minerals and high organic maturity. To reconstruct the last 30,000 years as an example of the transition between glacial and interglacial conditions a profile of sediment cores, recovered during the RV Polarstern" expedition ARK-VIIIl3 (ARCTIC '91), and additional sediment cores around Svalbard were investigated. Besides the mineralogy of different grain size fractions several additional sedimentological and organo-geochemical Parameterswere used. A detailed stratigraphic framework was achieved. By exploiting this data set changes in the mineral composition of the Eurasian Basin sediments can be related to climatic changes. Certain mineral compositions can even be associated with particular transport processes, e.g. the smectitel pyroxene association with sea ice transport from the eastern Kara Sea and the western Laptev Sea. Hence, it is possible to decipher the complex interplay between the influx of warm Atlantic waters into the Southwest of the Eurasian Basin, the waxing and waning of the Svalbard1Barents- Sea- and Kara-Sea-Ice-Sheets, the flooding of the Siberian shelf regions and the surface and deep water circulation. Until now the Arctic Ocean was assumed to be a rather stable System during the last 30,000 years which only switched from a completely ice covered situation during the glacial to seasonally Open waters during the interglacial. But this work using mineral assemblages of sediment cores in the vicinity of Svalbard revealed fast changes in the inflow of warm Atlantic water with the Westspitsbergen Current (< 1000 years), short periods of advances and retreats of the marine based Eurasian ice sheets (1000-3000 years), and short melting phases (400 years?). Deglaciation of the marine-based Eurasian and the land-based north American and Greenland ice sheets are not simultaneous. This thesis postulates that the Kara Sea Ice Sheet released an early meltwater signal prior to 15,000 14C years leading the Barents Sea Ice Sheet while the western land-based ice sheets are following later than 13,500 14C years. The northern Eurasian Basin records the shift between iceberg and sea-ice material derived from the Canadian Arctic Archipelago and N-Greenland and material transported by sea-ice and surface currents from the Siberian shelf region. The phasing of the deglaciation becomes very obvious using the dolomite and quartd phyllosilicate record. It is also supposed that the flooding of the Laptev Sea during the Holocene is manifested in a stepwise increase of sediment input at the Lomonosov Ridge between the Eurasian and Amerasian Basin. Depending on the strength of meltwater pulses from the adjacent ice sheets the Transpolar Drift can probably be relocated. These movements are traceable by the distribution of indicator minerals. Based on the outcome of this work the feasibility of bulk mineral determination can be qualified as excellent tool for paleoenvironmental reconstructions in the Arctic Ocean. The easy preparation and objective determination of bulk mineralogy provided by the QUAX software bears the potential to use this analyses as basic measuring method preceding more time consuming and highly specialised mineralogical investigations (e.g. clay mineralogy, heavy mineral determination).

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Includes publisher's advertisement, p. [4] of wrapper.

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Thomas Paine, with criticisms.

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With this is bound his Mistakes of Ingersoll on Thomas Paine, as shown by E. P. Goodwin. Chicago, 1880.

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Partly reprinted from various periodicals.

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Acoustic stimuli within the sonic range are effective triggers of C-type escape behaviours in fish. We have previously shown that fish have an acute sensitivity to infrasound also, with acceleration thresholds in the range of 10(-5) m s(-2). In addition, infrasound at high intensities around 10(-2) m s(-2) elicits strong and sustained avoidance responses in several fish species. In the present study, the possible triggering of C-escapes by infrasonic single-cycle vibrations was examined in juvenile roach Rutilus rutilus. The fish were accelerated in a controlled and quantifiable manner using a swing system. The applied stimuli simulated essential components of the accelerations that a small fish would encounter in the hydrodynamic flow field produced by a predatory fish. Typical C- and S-type escape responses were induced by accelerations within the infrasonic range with a threshold of 0.023 m s(-2) for an initial acceleration at 6.7 Hz. Response trajectories were on average in the same direction as the initial acceleration. Unexpectedly, startle behaviours mainly occurred in the trailing half of the test chamber, in which the fish were subjected to linear acceleration in combination with compression, i.e. the expected stimuli produced by an approaching predator. Very few responses were observed in the leading half of the test chamber, where the fish were subjected to acceleration and rarefaction, i.e. the stimuli expected from a suction type of predator. We conclude that particle acceleration is essential for the directionality of the startle response to infrasound, and that the response is triggered by the synergistic effects of acceleration and compression.

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Mussorgsky's Sunless cycle is aesthetically and stylistically an anomalous member of his oeuvre. Its notably effaced, pared-down, and withdrawn qualities present challenges to critical interpretation. Its uniqueness, however, renders it a crucial work for furnishing the fullest possible picture of Mussorgsky as a creative artist. The author of its texts, Golenishchev-Kutuzov (whose relationship with Mussorgsky at the time of its writing possibly extended beyond the platonic) has been identified by recent scholarship as an essential eye-witness for those to whom Stasov's populist characterization of the composer does not ring entirely true. Golenishchev-Kutuzov believed that in Sunless Mussorgsky first revealed his authentic artistic self. According to Golenishchev-Kutuvoz, Mussorgsky regarded his signal achievement in Sunless to have been the eradication of all elements other than feeling. In other words, he had thrown off the stylistic shackles imposed by the aesthetics of realism and relied entirely on intuitive harmonic invention as the sole conveyor of a purely subjective, affective meaning in the cycle. This hypothesis forms the point of departure for an investigation of select numbers of the cycle. Analysis reveals that the affective aspect is riot the only significant element operative. Alongside remnants of the realist style, there is evidence, of varying degrees of subtlety, for a knowing use of symmetrical pitch organization. Mussorgsky not only adapted the usual referential attachments of symmetrically based chromaticism-typically found in Russian operas of the second half of the nineteenth century-he also, through extremely simple but effective means, synthesized the intuitive harmonic and rational symmetrical elements of the cycle's pitch organization so that the latter emerges seamlessly out of the former. This remarkable synthesis ensures the cycle's uniformity of tone while also allowing for a reading that extends beyond the generally affective to the symbolically more specific. This symbolic level of reading offers several interpretative possibilities, one of which may refer even to the relationship of the poet and the composer. Irrespective of such potentials for interpretation, the most significant achievement in the cycle remains the synthesis of the intuitive/affective and rational/symbolic elements of its organization. Songs 1, 2, 3, and 6 of the cycle are considered in detail.

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Four experiments are reported that examine the ability of cricket batsmen of different skill levels to pick up advance information to anticipate the type and length of balls bowled by swing and spin bowlers. The information available upon which to make the predictive judgements was manipulated through a combination of temporal occlusion of the display and selective occlusion or presentation of putative anticipatory cues. In addition to a capability to pick up advance information from the same cues used by intermediate and low-skilled players, highly skilled players demonstrated the additional, unique capability to pick up advance information from some specific early cues (especially bowling hand and arm cues) to which the less skilled players were not attuned. The acquisition of expert perceptual-motor skill appears to involve not only refinement of information extraction but also progression to the use of earlier, kinematically relevant sources of information.

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A new control algorithm using parallel braking resistor (BR) and serial fault current limiter (FCL) for power system transient stability enhancement is presented in this paper. The proposed control algorithm can prevent transient instability during first swing by immediately taking away the transient energy gained in faulted period. It can also reduce generator oscillation time and efficiently make system back to the post-fault equilibrium. The algorithm is based on a new system energy function based method to choose optimal switching point. The parallel BR and serial FCL resistor can be switched at the calculated optimal point to get the best control result. This method allows optimum dissipation of the transient energy caused by disturbance so to make system back to equilibrium in minimum time. Case studies are given to verify the efficiency and effectiveness of this new control algorithm.

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Para atingir os objetivos propostos, ou seja, levantar e descrever indicadores socioculturais de uma amostra de adolescentes em cumprimento de medida socioeducativa, e descrever características psicológicas e de personalidade dos adolescentes infratores, num estudo que pesquisou adolescentes em cumprimento de medida socioeducativa. O trabalho foi realizado em duas as etapas: na primeira, os 47 adolescentes participaram de uma entrevista semidirigida; na segunda, dez desses adolescentes foram selecionados e submetidos a um instrumento projetivo para investigação de aspectos da personalidade: o “desenho da Figura Humana” de Machower, adaptado por Van Kolck (1956; 1984). A discussão teórica dos resultados baseou-se numa abordagem psicanalítica pós-freudiana para a compreensão da adolescência tanto como fase do desenvolvimento humano como dos comportamentos antissociais. Os resultados do estudo corroboraram a teoria advinda da literatura psicológica que aborda padrões comuns no período da adolescência, fase em que ocorre um complexo de fatores individuais da maturidade biológica associados ao meio social/cultural e que, por sua vez, estabelecem relações com as instâncias psicológicas ou psíquicas do sujeito junto com as características específicas de cada indivíduo. Na busca da compreensão desses padrões comuns da amostra dos adolescentes infratores utilizados no presente estudo, foram levantados dados do perfil psicossocial, cultural e demográfico; dos aspectos psicossociais e aspectos psicodinâmicos e de características de personalidade. A título de conclusão, o estudo destacou a problemática do adolescente em conflito com a lei, associada às questões sociais, de saúde mental, além do desenvolvimento psíquico, sinalizando a necessidade de ações psicoprofiláticas voltadas para população infantil, jovem, agrupamentos familiares e para a comunidade que representa seu entorno.

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A pesquisa tem por objetivo trabalhar o evento da Revolta de Jeú, em conjunto com a Estela de Dã, tendo como ponto de partida para tal, a exegese da perícope de 2 Reis 10-28,36. A história Deuteronomista apresenta o ato da Revolta de Jeú como sendo um feito demasiadamente importante, na restauração do culto a Javé em Israel, a partir de um contexto onde o culto a outras divindades, em Israel Norte, estava em pleno curso. No entanto, a partir da análise conjunta da Estela de Dã, que tem como provável autor o rei Hazael de Damasco, somos desafiados a ler esta história pelas entrelinhas não contempladas pelo texto, que apontam para uma participação ativa de Hazael, nos desfechos referentes a Revolta de Jeú, como sendo o responsável direto que proporcionou a subida de Jeú ao trono em Israel, clarificando desta forma este importante período na história Bíblica. Para tal análise, observar-se-á três distintos tópicos, ligados diretamente ao tema proposto: (1) A Revolta de Jeú e a Redação Deuteronomista, a partir do estudo exegético da perícope de 2 Reis 10,28-36, onde estão descritas informações pontuais sobre período em que Jeú reinou em Israel; (2) Jeú e a Estela de Dã, a partir da apresentação e análise do conteúdo da Estela de Dã, tratando diretamente dos desdobramentos da guerra em Ramote de Gileade, de onde se dá o ponto de partida à Revolta de Jeú; e por fim (3) O Império da Síria, onde a partir da continuidade da análise do conteúdo da Estela de Dã, demonstraremos a significância deste reino, além de apontamentos diretamente ligados ao reinado de Hazael, personagem mui relevante no evento da Revolta de Jeú.

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Purpose – To investigate the role of simulation in the introduction of technology in a continuous operations process. Design/methodology/approach – A case-based research method was chosen with the aim to provide an exemplar of practice and test the proposition that the use of simulation can improve the implementation and running of conveyor systems in continuous process facilities. Findings – The research determines the optimum rate of re-introduction of inventory to a conveyor system generated during a breakdown event. Research limitations/implications – More case studies are required demonstrating the operational and strategic benefits that can be gained by using simulation to assess technology in organisations. Practical implications – A practical outcome of the study was the implementation of a policy for the manual re-introduction of inventory on a conveyor line after a breakdown event had occurred. Originality/value – The paper presents a novel example of the use of simulation to estimate the re-introduction rate of inventory after a breakdown event on a conveyor line. The paper highlights how by addressing this operational issue, ahead of implementation, the likelihood of the success of the strategic decision to acquire the technology can be improved.

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The aim of this work was to design and build an equipment which can detect ferrous and non-ferrous objects in conveyed commodities, discriminate between them and locate the object along the belt and on the width of the belt. The magnetic induction mechanism was used as a means of achieving the objectives of this research. In order to choose the appropriate geometry and size of the induction field source, the field distributions of different source geometries and sizes were studied in detail. From these investigations it was found the square loop geometry is the most appropriate as a field generating source for the purpose of this project. The phenomena of field distribution in the conductors was also investigated. An equipment was designed and built at the preliminary stages of thework based on a flux-gate magnetometer with the ability to detect only ferrous objects.The instrument was designed such that it could be used to detect ferrous objects in the coal conveyors of power stations. The advantages of employing this detector in the power industry over the present ferrous metal electromagnetic separators were also considered. The objectives of this project culminated in the design and construction of a ferrous and non-ferrous detector with the ability to discriminate between ferrous and non-ferrous metals and to locate the objects on the conveying system. An experimental study was carried out to test the performance of the equipment in the detection of ferrous and non-ferrous objects of a given size carried on the conveyor belt. The ability of the equipment to discriminate between the types of metals and to locate the object on the belt was also evaluated experimentally. The benefits which can be gained from the industrial implementations of the equipment were considered. Further topics which may be investigated as an extension of this work are given.

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The high capital cost of robots prohibit their economic application. One method of making their application more economic is to increase their operating speed. This can be done in a number of ways e.g. redesign of robot geometry, improving actuators and improving control system design. In this thesis the control system design is considered. It is identified in the literature review that two aspects in relation to robot control system design have not been addressed in any great detail by previous researchers. These are: how significant are the coupling terms in the dynamic equations of the robot and what is the effect of the coupling terms on the performance of a number of typical independent axis control schemes?. The work in this thesis addresses these two questions in detail. A program was designed to automatically calculate the path and trajectory and to calculate the significance of the coupling terms in an example application of a robot manipulator tracking a part on a moving conveyor. The inertial and velocity coupling terms have been shown to be of significance when the manipulator was considered to be directly driven. A simulation of the robot manipulator following the planned trajectory has been established in order to assess the performance of the independent axis control strategies. The inertial coupling was shown to reinforce the control torque at the corner points of the trajectory, where there was an abrupt demand in acceleration in each axis but of opposite sign. This reduced the tracking error however, this effect was not controllable. A second effect was due to the velocity coupling terms. At high trajectory speeds it was shown, by means of a root locus analysis, that the velocity coupling terms caused the system to become unstable.

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The research developed in this thesis explores the sensing and inference of human movement in a dynamic way, as opposed to conventional measurement systems, that are only concerned with discrete evaluations of stimuli in sequential time. Typically, conventional approaches are used to infer the dynamic movement of the body; such as vision and motion tracking devices, with either a human diagnosis or complex image processing algorithm to classify the movement. This research is therefore the first of its kind to attempt and provide a movement classifying algorithm through the use of minimal sensing points, with the application for this novel system, to classify human movement during a golf swing. There are two main categories of force sensing. Firstly, array-type systems consisting of many sensing elements, and are the most commonly researched and commercially available. Secondly, reduced force sensing element systems (RFSES) also known as distributive systems have only been recently exploited in the academic world. The fundamental difference between these systems is that array systems handle the data captured from each sensor as unique outputs and suffer the effects of resolution. The effect of resolution, is the error in the load position measurement between sensing elements, as the output is quantized in terms of position. This can be compared to a reduced sensor element system that maximises that data received through the coupling of data from a distribution of sensing points to describe the output in discrete time. Also this can be extended to a coupling of transients in the time domain to describe an activity or dynamic movement. It is the RFSES that is to be examined and exploited in the commercial sector due to its advantages over array-based approaches such as reduced design, computational complexity and cost.