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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.
31

Separátor horniny / Rock Separator

Menoušek, Martin January 2012 (has links)
The aim of this master´s thesis is to design rock separator. It´s the mechanism, which separates clay from pirites. Main parametre which has been used in proposal is transporting kapacity 5 t/h.
32

Konstrukční návrh průběžného mísiče o výkonu 5-12 tun/hod / The design of sand mixer with output range 5-12 TPH

Bobkovič, Štefan January 2012 (has links)
The aim of this diploma thesis is the structural design of continous mixer with output range 5-12 tons per hour. The work contains a brief description of mixing technology and basic parameters of similar machines. The work is devoted to the design of double-arm sand mixer with a belt conveyor. An important part of this diploma thesis is a 3D model of fundamental parts of sand mixer, as well as its composition. Based on the 3D model is elaborated strenght analysis of selected parts with finite element method. The work is accompanied by manufacturing drawings of selected components and assembly drawing of deposit of mixing blades to the shaft.
33

A cost-effective design approach for multiple drive belt conveyor systems

Masaki, Mukalu Sandro January 2017 (has links)
Multiple drive belt conveyors are being increasingly incorporated in mining plans worldwide because of their high economic performance and the ease of moving these installations around, especially in underground mines. A typical modern multi-drive conveyor system consists of one or more intermediate drive stations positioned along the upper stretch of the conveyor and a single drive station situated in the lower stretch. Despite the acknowledged cost saving potential of the multiple drive technology, no previous work was reported on the methodology to realize a cost-effective design of multi-drive belt conveyors. This study investigates a design approach for multiple drive belt conveyors with the objective to achieve the lowest life cycle cost of multi-drive belt conveyors for a specified material transport task. For this purpose, an optimization model for the cost-effective design of multi-drive conveyor systems is formulated on the basis of the recommendations of the DIN 22101 and SANS 1313 standards. For a given number of intermediate drive stations, the proposed model optimizes a set of design parameters so that the minimum equivalent annual cost of a conveyor can be attained whilst handling the transport requirements and design conditions. The conveyor parameters optimized in this study are the rated powers of motors, the rated torques of gear reducers, the diameters and wrap angles of drive pulleys, the belt width, the belt speed, the lengths of the belt sections not nestled between drive pulleys, the spacings between idler rolls and the shell diameters and shaft diameters of idler rolls. For benchmark analysis purposes, a similar optimization model is also developed for the single drive technology. Described as mixed integer nonlinear programming (MINLP) problems, the two optimization models are solved using the MIDACO solver embedded in the MATLAB environment. The results of this study show the validity and effectiveness of the design model proposed for multi-drive belt conveyors. The results also indicate that the multiple drive technology is more beneficial for the conveying over long distances. The impact of the possible instability of inflation throughout the project lifetime is also investigated through three hypothetical scenarios, which involve a fixed inflation rate, a higher fluctuating inflation rate and a lower fluctuating inflation rate, respectively. The results of this sensitivity analysis show that the most cost-effective multi-drive belt conveyors obtained under a fixed inflation rate is robust enough against limited fluctuations of this parameter. / Dissertation (MEng)--University of Pretoria, 2017. / Electrical, Electronic and Computer Engineering / MEng / Unrestricted
34

A Vibratory Conveying System for Automatic Sorting of Lima Beans through Image Processing

Injante, Hugo, Gutierrez, Esteban, Vinces, Leonardo 01 September 2020 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / In order to comply with lima beans peruvian export standards, this study develops an automatic sorter machine. This system uses vibratory conveying to linearly move the grains and to allow their faces to rotate. In addition, image processing algorithms were used for the detection and rejection of defective lima beans. After performing 2200 sorting tests, an industrial performance with an efficiency of 96.81% in acceptance and 95.26% in product rejection was obtained
35

Low Voltage Current Conveyor Design Techniques / Techniky návrhu nízkonapěťových proudových konvejorů

El Dbib, Issa January 2008 (has links)
Disertační práce se zabývá proudovými konvejery CCII v proudovém modu s nízkým napájecím napětím. Potřeba velké rychlosti, vysokého výkonu a nízkého napájecího napětí pro mobilní elektroniku a komunikační systémy a potíže se současným stavem tlačí analogové návrháře k nalezení obvodové architektury a nové nízkopříkonové techniky. Je zde podrobně rozebrána technika složené kaskody a substrátu řízeného tranzistoru, která pomáhá produkci nízkopříkonových nízkovoltových obvodů. Dále jsou rozebrány a diskutovány základní funkční bloky, jako jsou proudová zrcadla, diferenční zesilovače a další, schopné pracovat při nízkých napájecích napětích. Jádrem práce je návrh konvejerů typu CCII s nízkým napájecím napětím. Jsou rozebrány jejich výhody a srovnání s konvenčními obvody. Princip a implementace operačního zesilovače založeného na proudovém konvejeru CCII je v práci navržen a popsán.
36

Investigation and Improvement of the Conveyor System at a Bottle Packaging Operation.

Fugate, Dirk Lee 18 August 2004 (has links) (PDF)
This investigation examines the bottle packaging conveyor system and its impact on the overall efficiency at a bottle packaging plant in Anderson, South Carolina. The purpose of this study is to demonstrate the existing opportunity to reduce bottle unit cost, increase productivity, decrease the risk of work related injuries, and improve line reliability along with employee moral with the conveying system alone. Data was gathered for this study in three ways: One, bottle packaging line lead operators were required to document the start and stop times of the conveyor system on their respective lines for six weeks. Two, a conveyor machine operator was required to document the start and stops of the conveyor system itself along with the cause for the same six weeks. Three, a packaging conveyor system project form was randomly submitted to 51 employees, soliciting their opinions and suggestions for the conveyor system. Conclusions of the study show opportunities for improvement and an overwhelming disapproval (88%) of the current system. Three improvement proposals were determined based on all the data collected.
37

Pohon pojezdu výsuvové hlavy pásového dopravníku / Travel drive of movable head belt conveyor

Pokorný, Prokop January 2015 (has links)
This master's thesis makes a brief comparison of design variants of belt conveyors with variable length including examples of use. The thesis is also deals with design of travel drive of movable head, witch is a part of propel station of belt conveyor for long distance belt conveyor systems. The thesis perform static analysis of steel structure of movable head. This thesis can serve as guidance for handling similar projects. Contains basic drawings of movable head steel structure and components of the movable head travel drive.
38

Návrh krokovacího roštu k odhrotovacím strojům / Design of stepping grate for deburring machines

Mazánek, Jan January 2017 (has links)
This master’s thesis is focused on design of stepper conveyor, that is used for transport od round bars of lengths from 3 m to 12 m and diameters from 20 mm to 100 mm between chamfering machines. It is a machinery assembled from chain conveyors and roller conveyors, which allows transverse and lengthwise movement of bars. The main goal was reduction of energetic demands compared to present solution of conveyor.
39

Modelování netradičních funkčních bloků v Pspice / Modeling of the unconventional functional blocks in Pspice

Zetík, Rostislav January 2009 (has links)
This master´s thesis on theme Modeling of the unconventional functional blocks in Pspice deals with the design procedures of electronic elements models and should to help with their create. At the beginning the thesis theoretically describes how the models are created and what possibilities for modeling the program Pspice offers. There are drawn near the individual levels of model and their properties. The second main part of thesis shows practically step by step the design procedures of models of the operational amplifier, current and voltage conveyors, OTA, CDTA, immittance inverter and converter and logarithmic amplifier. There are created the models up to 4.th level, the ideal, resistive, frequency dependent and nonlinear. The basic transmission properties, input and output impedance are modeled this way. The created models with sufficient accuracy correspond to the parameters of the commercial elements. This thesis such shows the possibilities of the program for finding of values for model components like stepping or Optimizer tool.
40

Univerzální aktivní prvky a jejich využití v kmitočtových filtrech / Universal active elements and their usage in frequency filters

Vencálek, Roman January 2009 (has links)
This master’s thesis deals with the advanced universal modern active elements, such as the current and voltage conveyors. The problem with small bandwidth has been fixed due to the quick development in recent years. Current and voltage conveyors are still being researched. The good properties of conveyors promise their possible commercial usage in the future. For the research of current conveyors we can use parts of other integrated circuits and thus get elements with similar properties. This thesis suggests how to make an active filter using the DBTA and FDBTA elements which were created by “combination” of the universal current and voltage conveyor. Simulations were carried out on selected circuits containing the DBTA to verify their properties. It was for finding out about their behaviour in real applications that the circuits were constructed. This enabled the comparison of the results acquired from the simulation programs with the ideal behaviour of the elements and with the models simulating real properties against the values acquired by measurements of the circuits.

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