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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Pojezdový mechanismus mostového jeřábu / The bridge crane's travel mechanism

Žid, Miroslav January 2018 (has links)
The aim of this master thesis is to design replacing the central drive of the overhead crane with dislocated drives. It´s a tong crane with the lifting capacity of 63 tons, located inside the hall. In the thesis is processed functional calculation of two types of drives, the associated types of brakes and the coupling element. Next there is a strength control of a new mechanism seat and a selected components. This whole leads to the output, which is the drawing documentation.
122

Výrobní hala / Assembly hall

Beran, Miroslav January 2019 (has links)
The diploma thesis deals with the design and assessment of the steel supporting structure of the production hall. The transverse dimension of the hall is 21,00 m, the longitudinal dimension is 70,00 m, the height of the hall is 17,56 m. S355 steel is used as the main supporting material. The supporting part of the hall consists of columns on which is placed a truss and two crane tracks at two height levels. Three different types of purlins and pillars are considered in the design of the steel structure. For the selected variant, a static calculation of the main bearing elements, including selected details, is drawn up and drawings are drawn up.
123

Posouzení únosnosti rámu kočky mostového licího jeřábu o nosnosti 120/40t - 21m / Verification of carrying capacity crab frame of ladle crane 120/40t - 21m

Hanzelka, Jan January 2011 (has links)
This diploma thesis deals with a steel construction of crab frame of ladle crane with lifting capacity of 120 and 40 tons and maximum lifting height of 21 meters. The aim of the work is analysis and assessment of the support frame of crane with a load of fatigue according to ČSN 27 0103/89. For this analysis is used thin shell and beam model. The diploma thesis was developed in cooperation with the Královopolska a.s. company.
124

Stavitelné rozpěrné zařízení pro zvedací práce v hale / The changeable strut devices for cranes in hall

Dvořáček, Jan January 2012 (has links)
This thesis was created for Bosch Rexroth in order to simplify the lifting work in the manufacturing hall. There was made the construction project of changeable strut devices for lifting loads. The project is comprised of two parts. The first deals with the analytical calculation and the second part consists of a numerical calculation using the finite element method.
125

Jeřábová kočka mostového jeřábu 32 t / Crane trolley 32 t

Knapec, Tomáš January 2015 (has links)
This master’s thesis is the design development of crane trolley, which is used to manipulate with scrap material. The target of this thesis is to develop a technical report including calculations of running and lifting gear, strength calculation of frame of trolley and drawings containing assembly of crane trolley and assemblies of running and lifting gear. Desired parameters of this trolley are maximum load capacity 32 000 kg, lifting height of 11 m, working lifting speed up to 10 m/min and working running speed up to 50 m/min.
126

Jeřáb radiální portálový / Radial gantry crane

Dias, Aleš January 2016 (has links)
The aim of my thesis is a conceptual design radial gantry crane including the important strength calculations according to the standards and examinations by means of ANSYS Workbench. The lifting capacity is 1500 kg, the length of the boom is 12 000 mm and the height of lifting is 3600mm. The crane is designed as fully revolving and the angle turning is 360°. The work also includes the selection of a suitable lifting gear from the manufacturer´s catalogue including the accessories casters, all important components and also FEM construction analysis.
127

Improved truck engine control for crane driving : - Focusing on fuel consumption / Förbättrad lastbilsmotorstyrning vid krankörning : - Med fokus på bränsleförbrukning

Svensson, Martin January 2008 (has links)
Due to increased demands on fuel economy the question of a more intelligent engine control for driving a truck-mounted crane has been raised. The aim of this thesis is to develop a new engine control for crane driving. The primary concern for the new engine control is fuel economy, but other factors, such as driver environment and drivability, have been taken into consideration as well. A literature study investigating engine control in construction machines has also been carried out and the results are presented in this report. Due to the fact that the hydraulic control system as well as the diesel engine control system is designed by the same construction machine manufacturer, more complex control strategies are utilized in these applications. In order to test the new control strategy a full-scale test has been carried out on a Scania truck with a crane from Hiab. The results point towards lower fuel consumption, better driver experience and lower noise levels. Some of the control features of the new control are suggested to be placed in the crane, and some in the truck. Only a small expansion of the communication between truck and crane would be necessary in order for the new control strategy to work. The experiences from the literature study point on several features utilized in construction machines that could be implemented in the crane control of the future. / På grund av ökade krav på minskad bränsleförbrukning har frågan om en förbättrad motorstyrning vid krankörning av lastbilsmonterade kranar blivit aktuell. Målet för detta examensarbete är att utveckla en ny motorstyrning anpassad för krankörning. I första hand syftar den nya motorstyrningen till att minska bränsleförbrukningen, men även andra faktorer såsom förarmiljö och körbarhet har tagits hänsyn till. En litteraturstudie om motorstyrning i hydrauliska grävmaskiner och andra hydrauliska maskiner har också utförts och resultatet finns presenterat i denna rapport. Eftersom det hydrauliska styrsystemet såväl som dieselmotorstyrsystemet är sammansatt hos en och samma tillverkare används mer komplicerade styralgoritmer i dessa tillämpningar. För att testa den nyutvecklade motorstyrningen har fullskaletest utförts på en Scanialastbil utrustad med en kran från Hiab. Resultaten pekar på lägre bränsleförbrukning, bättre förarupplevelse och lägre ljudnivå. Somliga av funktionerna i den nya styrningen föreslås placeras i lastbilen och andra i kranen. Bara en mycket liten utvidgning av kommunikationen mellan kran och lastbil skulle behövas för att denna styralgoritm skulle fungera. Lärdomarna ifrån litteraturstudien visar på att flera av de styrfunktioner som används ibland annat grävskopor skulle kunna komma till nytta i motor- och kran styrningen i en lastbilsmonterad kran i framtiden.
128

Optimization of operative planning in rail-road terminals

Bruns, Florian 16 September 2014 (has links)
Rail-road terminals are the chain links in intermodal rail-road transportation where standardized load units (containers, swap bodies and trailers) are transfered from trucks to trains and vice versa. We consider three subproblems of the operational planning process at rail-road terminals that terminal operators are facing in their daily operations. These are the optimization problems storage planning, load planning and crane planning. The aim of storage planning is to determine load unit storage positions for a set of load units in a partially filled storage area. Here, different restrictions like non-overlapping of stored load units have to be respected. The objective of storage planning is to minimize the total transportation costs and the number of load units that are not stored at the ground level. For the load planning we assume a scenario of overbooked trains. So, the aim of load planning is to assign a subset of the load units that are booked on a train to feasible positions on the wagons such that the utilization of the train is maximized and the costs for the handling in the terminal are minimized. For the feasible positioning of load units length and weight restrictions for the wagons and the train have to be respected. For the load planning of trains we consider a deterministic version and a robust approach motivated by uncertainty in the input data. The last considered optimization problem is the crane planning. The crane planning determines the transfer of the load units by crane between the different transportation modes. For each crane a working plan is computed which contains a subset of the load units that have to be handled together with individual start times for the transfer operations. For the load units which have to be transfered in the terminal, storage and load planning compute destination positions (inside the terminal). These destination positions are part of the input for the crane planning. The main objective of crane planning is to minimize the total length of the empty crane moves that have to be performed between successive transports of load units by the cranes. We provide MIP-models for all three subproblems of the operational planning process at rail-road terminals. For the storage and crane planning we also propose fast heuristics. Furthermore, we present and compare computational results based on real world data for all subproblems. The main contributions of this thesis concern load and storage planning. For the deterministic load planning we provide the first model that represents all practical constraints including physical weight restrictions. For the load planning we furthermore present robustness approaches for different practical uncertainties. For the storage planning we provide complexity results for different variants. For the practical setting we developed a heuristic which is able to compute solutions of high quality in a small amount of runtime.
129

« Rentrer dans le monde » : parcours d’une inquiétude chez les poètes Guillaume Apollinaire, Blaise Cendrars, T.S. Eliot, Federico García Lorca et Hart Crane / Poetry and Ideology : “Back to the world” with poets Guillaume Apollinaire, Blaise Cendrars, T.S. Eliot, Federico García Lorca and Hart Crane

Montin, Sandrine 04 December 2009 (has links)
Les poètes du début du vingtième siècle sont inquiets : hésitant entre idéalisme et matérialisme, liberté et déterminisme, création et évolution, ils errent dans une « zone » idéologique. Dans les premiers textes de Guillaume Apollinaire (1880-1918), Blaise Cendrars (1887-1961), T.S. Eliot (1888-1965), Federico García Lorca (1898-1936) et Hart Crane (1899-1932), le désarroi est permanent. Il s’incarne sous différentes formes, du dédoublement de personnalité à l’extrême lassitude, tandis que l’ombre et un vent de fin du monde envahissent les poèmes. Les positions des poètes varient entre nihilisme, incertaines tentatives de syncrétisme et ironie mordante. Pourtant, passé leur première jeunesse, ils reconnaissent que leur inquiétude n’est pas une donnée personnelle mais un fait d’époque, peut-être même le fait essentiel, sur le plan de la pensée, de l’époque dite moderne : c’est « l’âge de la comparaison », selon les mots de Nietzsche. Ils renoncent alors à exprimer la singularité d’une vision individuelle, originale, voire bizarre, pour « rentrer dans le monde ». Rompant nettement avec les objectifs littéraires du symbolisme, ils entendent désormais devenir « la conscience de l’époque », exposer les idéologies incompatibles qui s’y côtoient, faire l’inventaire de ses contrastes. Dans le premier tiers du vingtième siècle, l’inquiétude idéologique est le mobile qui engage les poètes à redéfinir leur fonction dans la cité et l’un des grands moteurs de l’innovation esthétique : cubisme, simultanéisme, dialogisme et lyrisme épique. C’est ce parcours dont nous espérons dégager la cohérence et les principales étapes. / At the beginning of the XXth century poets were unsettled : hesitating between idealism and materialism, freedom and determinism, creation and evolution, they wandered in an ideological « waste land ». In the early works of Guillaume Apollinaire (1880-1918), Blaise Cendrars (1887-1961), T.S. Eliot (1888-1965), Federico García Lorca (1898-1936) and Hart Crane (1899-1932), distress assumed different forms: from split personality to extreme weariness. The poets’ positions bounced between nihilism, half-hearted attempts at syncretism and bitter irony. As they matured, they recognized however that their restlessness was not a personal matter but a product of the times, perhaps even the main feature, on the level of thought, of the so-called modern times : “the age of comparison”, in Nietzsche’s words. They then renounced to express the singularity of an individual, original, even bizarre vision, and chose to “go back to the world”. Breaking with the literary goals of symbolism, they aimed at becoming the “conscience of the times”, at exposing their conflicting ideologies, and at listing their contrasts. In the first third of the twentieth century, this ideological restlessness pushed poets to redefine their role in the city. It was one of the most powerful forces behind aesthetic innovation: cubism, simultaneism, dialogism and epic lyricism. In this study, we will examine the coherence and main stages of this process.
130

The BCS algorithm: optimizing crane schedules on multiple bays in conjunction with continuous time simulation

Strieby, James January 1900 (has links)
Master of Science / Department of Industrial & Manufacturing Systems Engineering / Todd Easton / This thesis introduces the Bay Crane Scheduling (BCS) problem and related BCS algorithm. The purpose of this algorithm is to optimize the assignment of jobs to overhead cranes as well as the sequence in which each crane performs its assigned jobs. This problem is unique from other Overhead Crane Scheduling (OCS) problems through its increased complexity. Up until now, OCS problems involve a set number of cranes operating in a single common area, referred to as a bay, and are unable to pass over each other. The BCS problem involves a varying number of active cranes operating in multiple bays. Each crane is allowed to move from one bay to the next, through specific locations called bridges. This is crucial to completing certain “special” jobs that require two cranes operating in unison to transport an item. The BCS algorithm employs two continuous time simulations in conjunction with an initial job-assignment algorithm and a Simulated Annealing (SA) improvement heuristic in order to minimize the non-productive crane time, while avoiding overloading any crane. To the extent of the author’s knowledge, this is the first time a continuous time simulation has been used to model an OC system. The BCS algorithm was originally developed for a large manufacturing facility, and when it was tested against the facility’s current scheduling methods, it shows a 20% improvement in the overall active crane time required to complete equivalent set of jobs. This improved efficiency is crucial to the manufacturing facility being able to increase its production rate without the addition of new cranes. In addition, BCS is statistically shown to be superior to the current strategy. The results from BCS are substantial and practitioners are encouraged to utilize BCS’s methodologies to improve other overhead crane systems.

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