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1
Kasichainula, Nagesh. "Mechanic characterization of reinforced rigid polyurethane foams /." free to MU campus, to others for purchase, 2003. http://wwwlib.umi.com/cr/mo/fullcit?p1418038.
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Liu, Jianhui. "Dynamic behaviour of rigid-plastic beams." Thesis, University of Liverpool, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.480541.
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Kamyab, Morad. "Deformation of soft plastic solids by rigid walls." Thesis, Imperial College London, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241826.
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Vaziri, Reza. "Finite deflection dynamic analysis of rigid-plastic beams." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25142.
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An analytical procedure, which retains the influence of finite deflections,
is developed herein for the dynamic behaviour of rectangular shaped rigid-plastic beams. In the general formulation of the problem deformation is assumed to proceed under two distinct mechanisms depending on the extent to which the value of the peak pressure exceeds the static collapse pressure of the beam. These mechanisms are described by kinernatically admissible velocity fields that satisfy the appropriate continuity conditions. The governing equations of motion are derived from a variational
statement consisting of the principle of virtual work and D'Alembert's principle. The conventional parabolic yield surface (which describes the coupling action between axial forces and bending moments at yield) and its associated flow rule are adopted to describe the plastic behaviour of the beam material. The kinematic small but finite deflection analysis, in which the membrane forces and bending moments interact, generally leads to basic equations which are of nonlinear character. These resulting equations
are solved analytically and closed form expressions are developed for the prediction of maximum permanent deformation of the beam. A dynamic membrane analysis is carried out in those cases when the input energy is sufficiently high that the beam undergoes moderately large deformation (i.e. deflections of the order of beam thickness). Finally the dependence of the permanent deflection on the applied pressure and impulse is obtained for a family of rectangular pulses. This relationship is represented by an isoresponse curve in a form convenient for direct engineering use.<br>Applied Science, Faculty of<br>Civil Engineering, Department of<br>Graduate
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Khan, Azam. "Behaviour of rigid plastic structures under extreme dynamic loading." Thesis, Imperial College London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.501756.
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Schubak, Robert Brian. "Nonlinear rigid-plastic analysis of stiffened plates under blast loads." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/31482.
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The large ductile deformation response of stiffened plates subjected to blast loads is investigated and simplified methods of analysis of such response are developed. Simplification
is derived from modelling stiffened plates as singly symmetric beams or as grillages thereof. These beams are further assumed to behave in a rigid, perfectly plastic manner and to have piecewise linear bending moment-axial force capacity interaction relations, otherwise known as yield curves.
A blast loaded, one-way stiffened plate is modelled as a singly symmetric beam comprised
of one stiffener and its tributary plating, and subjected to a uniformly distributed line load. For a stiffened plate having edges fully restrained against rotations and translations,
both transverse and in-plane, use of the piecewise linear yield curve divides the response of the beam model into two distinct phases: an initial small displacement phase wherein the beam responds as a plastic hinge mechanism, and a final large displacement phase wherein the beam responds as a plastic string. If the line load is restricted to be a blast-type pulse, such response is governed by linear differential equations and so may be solved in closed form. Examples of a one-way stiffened plate subjected to various blast-type pulses demonstrate good agreement between the present rigid-plastic formulation and elastic-plastic beam finite element and finite strip solutions.
The response of a one-way stiffened plate is alternatively analysed by approximating it as a sequence of instantaneous mode responses. An instantaneous mode is analogous to a normal mode of linear vibration, but because of system nonlinearity exists for only the instant and deformed configuration considered. The instantaneous mode shapes are
determined by an extremum principle which maximizes the rate of change of the stiffened plate's kinetic energy. This approximate rigid-plastic response is not solved in closed form but rather by a semi-analytical time-stepping algorithm. Instantaneous mode solutions compare very well with the closed-form results.
The instantaneous mode analysis is extended to the case of two-way stiffened plates, which are modelled by grillages of singly symmetric beams. For two examples of blast loaded two-way stiffened plates, instantaneous mode solutions are compared to results from super finite element analyses. In one of these examples the comparison between analyses is extremely good; in the other, although the magnitudes of displacement response
differ between the analyses, the predicted durations and mechanisms of response are in agreement.
Incomplete fixity of a stiffened plate's edges is accounted for in the beam and grillage models by way of rigid-plastic links connecting the beams to their rigid supports. Like the beams, these links are assumed to have piecewise linear yield curves, but with reduced bending moment and axial force capacities. The instantaneous mode solution is modified accordingly, and its results again compare well with those of beam finite element analyses.
Modifications to the closed-form and instantaneous mode solutions to account for strain rate sensitivity of the panel material are presented. In the closed-form solution, such modification takes the form of an effective dynamic yield stress to be used throughout the rigid-plastic analysis. In the time-stepping instantaneous mode solution, a dynamic yield stress is calculated at each time step and used within that time step only. With these modifications in place, the responses of rate-sensitive one-way stiffened plates predicted by the present analyses once again compare well with finite element and finite strip solutions.<br>Applied Science, Faculty of<br>Civil Engineering, Department of<br>Graduate
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Yeung, Richard Ching King. "Rigid-plastic finite element analysis of static and dynamic collapse." Thesis, Imperial College London, 1986. http://hdl.handle.net/10044/1/38201.
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Sahlit, Carmen Lucia de Mesquita. "Mathematical programming methods for dynamically loaded rigid-plastic framed structures." Thesis, Imperial College London, 1992. http://hdl.handle.net/10044/1/7819.
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Tong, C. S. "The elastic-plastic behaviour of semi-rigid connections in steel structures." Thesis, University of Hertfordshire, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354321.
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O'Connor, John. "The flexural behaviour of sandwich beams with thick facings and rigid plastic foam cores." Thesis, University of Ulster, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250274.
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Mendes, Maria Mafalda da Cunha Policarpo Ferreira. "Growing globally: Is it reasonable for Logoplaste to enter the Colombian rigid plastic packaging market?" Master's thesis, NSBE - UNL, 2014. http://hdl.handle.net/10362/11908.
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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics<br>With this project my main goal is to understand which internationalization opportunities still exist for Logoplaste and more precisely name a country where I believe this company’s business model may work.
I began with a deep analysis on the company, its business model, research on where it succeeded and why. Afterwards, I supported the gathered knowledge with some theoretical concepts. At this point, I decided to explore the concept of strategic outsourcing and modularity. Additionally, I chose to refer to a couple of commonly known frameworks such as Porter’s Generic Value Chain and the VRINO Framework as well as to a couple of theories, namely the Transaction Cost Theory and the Resource Based View.
Once all Logoplaste knowledge was gathered, it was time to analyze the potential internationalization opportunities: China, Colombia, India, Indonesia, Peru, and Turkey. During this phase, in addition to an extensive research of macroeconomic indicators I also resorted to Ghemawat’s famous CAGE model to help me narrow down the various hypotheses. I was then finally able to conclude that Colombia seemed an attractive market.
It was now necessary to analyze Colombia with more detail and therefore I used a PESTLE analysis to get a better idea of this country’s macro-environment. A SWOT analysis and a Porter’s five forces analysis followed with the aim of understanding how could Logoplaste fit in this country. To finalize, I described briefly the overall implementation procedure including a listing of the major costs incurred in, if Logoplaste decided to move forward with this project in Colombia.
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Heng, Piseth. "Simplified mechanical models for the nonlinear dynamic analysis of elasto-plastic steel structures impacted by a rigid body." Doctoral thesis, KTH, Bro- och stålbyggnad, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-217281.
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Buildings subjected to impact and explosion are usually studied using large scale and highly nonlinear finite element model which are time-consuming. The first part of the thesis deals with the development of simple and accurate models for evaluating the nonlinear inelastic behaviour of steel frame structures subjected to impact. The research work in this part has produced four simplified models. The first model concerns with a 4DOF model that reproduces the behaviour of the impacted column. The restraining effect from the rest of the structure is modelled by an elastic spring, a head mass and a static load applied at the top of the column. In the second model, the impacted column is then further simplified using a SDOF model. The behaviour of the SDOF model is governed by an analytical force-displacement expressions of the column loaded by a located force. The maximum displacement of the impacted column can also be determined explicitly by adopting an energy-equivalent approach. Afterwards, in an effort to model the whole structure, two finite element models are developed. For these models, a co-rotational super-element that consists of a beam element and two generalized elasto-plastic hinges is obtained by performing a static condensation. An elastic flexible beam element is used in the first finite element model, whereas a rigid beam element is considered in the second one. In these models, inelasticity is concentrated at generalized elasto-plastic hinges which are modelled by combined axial-rotational springs. The behaviour of the hinges is uncoupled in the elastic range while an axial-bending interaction is considered in the plastic range making it possible to reproduce a wide range of cross-sections and joints. In addition, unilateral contact between rigid point masses is considered and the energy loss during impact is accounted by means of a restitution coefficient following Newton’s impact law. Energy-momentum scheme is used to solve the equations of motion produced by these models. The second part of the thesis concerns with the performance of the connectors in composite steel-concrete slabs under explosion. The purpose is to determine residual capacities of the shear connectors after being damaged by explosion using large-scale pull-out and push-out experimental tests and finite element simulations.<br><p>QC 20171106</p>
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Almeida, João Francisco Coelho Mateus Martins de. "Internationalization project - Logoplaste in the Turkish market." Master's thesis, NSBE - UNL, 2014. http://hdl.handle.net/10362/11824.
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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics<br>This thesis project aims to be a successful instrument for Logoplaste’s management team if they received a proposal to invest in the Turkish market. In the project I studied not only Logoplaste’s value chain but also its competitive advantages and how the company can handle them in order to be successful in this market. Moreover, it contains a careful analysis of the Turkish market that helps to understand how the market accepts Foreign Direct Investment and also to understand if there are attractive business opportunities for Logoplaste.
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Rivera, Alejandro. "Non-Linear Finite Element Method Simulation and Modeling of the Cold and Hot Rolling Processes." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/31035.
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A nonlinear finite element model of the hot and cold rolling processes has been developed for flat rolling stock with rectangular cross section. This model can be used to analyze the flat rolling of cold and hot steel rectangular strips under a series of different parameters, providing the rolling designer with a tool that he can use to understand the behavior of the steel as it flows through the different passes.
The models developed, take into account all of the non-linearities present in the rolling problem: material, geometric, boundary, and heat transfer. A coupled thermal-mechanical analysis approach is used to account for the coupling between the mechanical and thermal phenomena resulting from the pressure-dependent thermal contact resistance between the steel slab and the steel rolls.
The model predicts the equivalent stress, equivalent plastic strain, maximum strain rate, equivalent total strain, slab temperature increase, increase in roll temperature, strip length increase, slab thickness % reduction (draft), and stripâ s velocity increase, for both the cold and hot rolling processes. The FE model results are an improvement over the results obtained through the classical theory of rolling. The model also demonstrates the role that contact, plastic heat generation and friction generated heat plays in the rolling process.
The analysis performed shows that the steel in cold rolling can be accurately modeled using the elastic-plastic (solid Prandtl-Reuss) formulation, with a von Mises yield surface, the Praguer kinematic hardening rule, and the Ramberg-Osgood hardening material model. The FE models also demonstrate that the steel in hot rolling can be modeled using the rigid-viscoplastic (flow Levy-Mises) formulation, with a von Mises yield surface, and Shidaâ s material model for high temperature steel where the flow stress is a function of the strain, strain rate, and the temperature.
Other important contributions of this work are the demonstration that in cold rolling, plane sections do not remain plane as the classic theory of rolling assumes. As a consequence, the actual displacements, velocity, and stress distributions in the workpiece are compared to and shown to be an improvement over the distributions derived from the classical theory. Finally, the stress distribution in the rolls during the cold rolling process is found, and shown to be analogous to the stress distribution of the Hertz contact problem.<br>Master of Science
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Cordero, Raymundo. "Limit state analysis : adaptive finite element upper and lower bound approach to the evaluation of the limit load of a Von Mises rigid-plastic material body in plane stress." Thesis, Swansea University, 2005. https://cronfa.swan.ac.uk/Record/cronfa42326.
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A new approach to the computation of the Limit load of a Von Mises rigid-plastic material structure modelled in plane stress is assessed. Most international design codes require the engineer to establish the safety of a structure for a given set of design loads under the so-called limit state conditions. The limit state represents the failure point at which the structure begins to exhibit unbounded deformations. Under limit state conditions, the deformation of the solids tend to concentrate on thin failure bands, known as slip-lines. This makes the finite element analysis a challenging task as the mesh needs to be adapted to capture these bands accurately. In order to achieve this, an adaptive technique is required whereby the error produced in each finite element is measured and if required the element is subdivided automatically. In order to measure this error both an upper and lower bound of the exact solution need to be evaluated. In this thesis, a novel technology to obtain the lower bound is derived and implemented together with mesh adaptivity technology. A lower bound is found from a state of stresses in equilibrium with the external forces. The proposed technique obtains such equilibrated state using the stresses obtained during the upper bound evaluation. These stresses, although not strictly in equilibrium, can be balanced using procedures available in the literature. The present aim of the research project is to develop numerical technology based on the finite element method to calculate the limit state of two-dimensional solids in plane stress. The upper bound theorem of limit analysis is implemented by means of a Lagrangian optimization technique solved by the Newton-Raphson method with Line Search. A control parameter to deal with the singularity of the tangent stiffness matrix due to the yielding condition is used along the range of admissible rate of deformations for a rigid-plastic material. The lower bound theorem is then applied by performing a technique to equilibrate the interelement tractions, kinematically solving a sequence of local problems using the equilibrated tractions as an updated load input, which lets us determine the elementwise contribution to both the upper and lower bounds. An adaptive technique is then implemented, based on the elemental contributions to the difference between the upper bound and the lower bound of the collapse multiplier. Both non-adaptive and adaptive results are evaluated. Results show a good performance of the solution technique, both in comparison with well known plane stress bound values and also in the graphical output obtained in the form of refined regions which describe the occurrence of slip-line patterns and/or localized yielding regions.
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Raithatha, Ankor Mahendra. "Incremental sheet forming : modelling and path optimisation." Thesis, University of Oxford, 2008. http://ora.ox.ac.uk/objects/uuid:89b0ac1e-cab4-4d80-b352-4f48566c7668.
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Incremental sheet forming (ISF) is a novel metal shaping technology that is economically viable for low-volume manufacturing, customisation and rapid-prototyping. It uses a small tool that is controlled by a computer-numerically controlled sequence and the path taken by this tool over the sheet defines the product geometry. Little is currently known about how to design the tool-path to minimise geometric errors in the formed part. The work here addresses this problem by developing a model based tool-path optimisation scheme for ISF. The key issue is how to generate an efficient model for ISF to use within a path optimisation routine, since current simulation methods are too slow. A proportion of this thesis is dedicated to evaluating the applicability of the rigid plastic assumption for this purpose. Three numerical models have been produced: one based on small strain deformation, one based on limit analysis theory and another that approximates the sheet to a network of rods. All three models are formulated and solved as second-order cone programs (SOCP) and the limit analysis based model is the first demonstration of an upper-bound shell finite element (FE) problem solved as an SOCP. The models are significantly faster than commercially available FE software and simulations are compared with experimental and numerical data, from which it is shown the rigid plastic assumption is suitable for modelling deformation in ISF. The numerical models are still too slow for the path optimisation scheme, so a novel linearised model based on the concept of spatial impulse responses is also formulated and used in an optimal control based tool-path optimisation scheme for producing axisymmetric products with ISF. Off-line and on-line versions of the scheme are implemented on an ISF machine and it is shown that geometric errors are significantly reduced when using the proposed method. This work provides a new structured framework for tool-path design in ISF and it is also a novel use of feedback to compensate for geometrical errors in ISF.
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Pigg, W. "The fibre reinforcement of low density rigid polyurethane foam." Thesis, Manchester Metropolitan University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372751.
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Kasinos, Stavros. "Seismic response analysis of linear and nonlinear secondary structures." Thesis, Loughborough University, 2018. https://dspace.lboro.ac.uk/2134/33728.
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Understanding the complex dynamics that underpin the response of structures in the occurrence of earthquakes is of paramount importance in ensuring community resilience. The operational continuity of structures is influenced by the performance of nonstructural components, also known as secondary structures. Inherent vulnerability characteristics, nonlinearities and uncertainties in their properties or in the excitation pose challenges that render their response determination as a non-straightforward task. This dissertation settles in the context of mathematical modelling and response quantification of seismically driven secondary systems. The case of bilinear hysteretic, rigid-plastic and free-standing rocking oscillators is first considered, as a representative class of secondary systems of distinct behaviour excited at a single point in the primary structure. The equations governing their full dynamic interaction with linear primary oscillators are derived with the purpose of assessing the appropriateness of simplified analysis methods where the secondary-primary feedback action is not accounted for. Analyses carried out in presence of pulse-type excitation have shown that the cascade approximation can be considered satisfactory for bilinear systems provided the secondary-primary mass ratio is adequately low and the system does not approach resonance. For the case of sliding and rocking systems, much lighter secondary systems need to be considered if the cascade analysis is to be adopted, with the validity of the approximation dictated by the selection of the input parameters. Based on the premise that decoupling is permitted, new analytical solutions are derived for the pulse driven nonlinear oscillators considered, conveniently expressing the seismic response as a function of the input parameters and the relative effects are quantified. An efficient numerical scheme for a general-type of excitation is also presented and is used in conjunction with an existing nonstationary stochastic far-field ground motion model to determine the seismic response spectra for the secondary oscillators at given site and earthquake characteristics. Prompted by the presence of uncertainty in the primary structure, and in line with the classical modal analysis, a novel approach for directly characterising uncertainty in the modal shapes, frequencies and damping ratios of the primary structure is proposed. A procedure is then presented for the identification of the model parameters and demonstrated with an application to linear steel frames with uncertain semi-rigid connections. It is shown that the proposed approach reduces the number of the uncertain input parameters and the size of the dynamic problem, and is thus particularly appealing for the stochastic assessment of existing structural systems, where partial modal information is available e.g. through operational modal analysis testing. Through a numerical example, the relative effect of stochasticity in a bi-directional seismic input is found to have a more prominent role on the nonlinear response of secondary oscillators when compared to the uncertainty in the primary structure. Further extending the analyses to the case of multi-attached linear secondary systems driven by deterministic seismic excitation, a convenient variant of the component-mode synthesis method is presented, whereby the primary-secondary dynamic interaction is accounted for through the modes of vibration of the two components. The problem of selecting the vibrational modes to be retained in analysis is then addressed for the case of secondary structures, which may possess numerous low frequency modes with negligible mass, and a modal correction method is adopted in view of the application for seismic analysis. The influence of various approaches to build the viscous damping matrix of the primary-secondary assembly is also investigated, and a novel technique based on modal damping superposition is proposed. Numerical applications are demonstrated through a piping secondary system multi-connected on a primary frame exhibiting various irregularities in plan and elevation, as well as a multi-connected flexible secondary system. Overall, this PhD thesis delivers new insights into the determination and understanding of the response of seismically driven secondary structures. The research is deemed to be of academic and professional engineering interest spanning several areas including seismic engineering, extreme events, structural health monitoring, risk mitigation and reliability analysis.
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Plaskett, Amanda May. "The effect of calcium carbonate fillers on fusion and properties of rigid PVC." Thesis, Loughborough University, 1989. https://dspace.lboro.ac.uk/2134/27223.
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Although the addition of fillers both coated and uncoated to PVC compounds is now commonplace, research into their role in the fusion process and subsequent end product properties is limited. Thus five grades of natural calcium carbonate filler of varying particle size were incorporated into a simple rigid PVC pipe formulation by dry blending and then extrusion on a twin screw extruder.
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Lehner, Carmen. "Evaluating a new plant startup in the rigid plastics packaging industry." Thesis, Pepperdine University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10142125.
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<p> This qualitative study examined the startup phase of a new manufacturing facility in the rigid plastics packaging industry. Thirteen personnel were interviewed for their impressions of the startup experience, and were asked for their recommendations for the type of leadership, training and knowledge sharing, and organizational systems and support needed for a new plant startup to succeed. Participants noted both successes and challenges related to the plant manager, training and support delivered, and communication and other organizational systems in place. Participants offered several recommendations, including improving leader selection and preparation; optimizing training resources, schedules, and materials for each area; improving coordination, communication, and training for visiting support staff; and adapting human resources, project management, and equipment. Based on these findings, several recommendations for executive leaders, project management, and organization development consultants were identified. The key suggestion for continued research is to repeat the study with an enhanced research design. </p>
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Fabián, Vargas Claudia Fiorella, Sánchez Marko Edinnson Polo, and Castro Mario Antonio Orna. "Propuesta para optimizar la gestión de inventarios en Amcor Rigid Plastics del Perú S.A." Master's thesis, Universidad del Pacífico, 2016. http://hdl.handle.net/11354/1515.
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La presente tesis busca ejecutar un estudio de la cadena de abastecimiento de Amcor Rigid Plastics del Perú S.A., empresa con 15 años de presencia en el mercado peruano con capitales suizos, australianos y peruanos, dedicados a la fabricación de envases de plástico PET1 para la industria de bebidas. Este estudio considera el diagnóstico, análisis y una propuesta de mejora que permitan llevarla desde su situación operativa actual, hasta una con resultados de ahorros y mejoras financieras, garantizando un nivel de servicio competitivo con herramientas y metodologías comprobadas que le permitan lograr un alcance interfuncional, donde se maximice la utilidad de la compañía.
Para esto, hemos dividido el presente trabajo en siete capítulos. El primero presenta la introducción del trabajo de tesis; se describe en grandes rasgos, la industria, la empresa y la problemática de Amcor.
El segundo capítulo contiene el marco teórico, donde se explica las principales teorías y metodologías utilizadas para el desarrollo de esta investigación y la forma en que fueron aplicadas, entre las cuales podemos mencionar el VSM - Value Stream Mapping (Martin & Osterling, 2014); los controladores de la cadena de suministro (Chopra, 2013); las cinco fuerzas de Porter (Porter M. E., 2009); el MRP – Material Requirement Planning (Ptak & Smith, 2011); el S&OP (Wallace, 2004) – Sales and Operation Planning, y el IBP – Integrated Business Planning (Palmatier, Crum, & Wight, 2013).
El tercer capítulo detalla el análisis externo, para lo cual se estudiaron los entornos socioeconómico, legal, tecnológico y ambiental del mercado mundial y nacional, para construir con ayuda del análisis de las cinco fuerzas de Porter, el mapa de competitividad de Amcor frente al poder de negociación de sus clientes, proveedores, competidores existentes y la amenaza de productos sustitutos y nuevos competidores.<br>Trabajo de investigación
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Masha, Lerato Kennilworth. "Assessment of Nampak’s implementation of world class manufacturing strategy within the Nampak Plastic Rigids division." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/97414.
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Thesis (MBA)--Stellenbosch University, 2014.<br>ENGLISH ABSTRACT: World Class Manufacturing (WCM) was first introduced into Nampak in 1990, and since then, there have been three attempts by the organisation to re-implement WCM in the organisation. In the last 23 years, 1990-2013, no formal assessment has been done with regard to evaluating whether the introduction of WCM was effective or not in the organisation, according to the goals and objectives set when the projects were initially implemented.
The aim of this research report was to evaluate whether the implementation of WCM was effective in the Nampak Plastic Rigids (PRs) clusters and the study focused on only three operations namely; Nampak Tubes, Closures and Megapak. Secondly, the research aimed to establish what elements were required to successfully implement and sustain WCM in an organisation.
Through the research it was established that in order to implement and sustain WCM successfully the following elements are required; strategy alignment, strategy implementation or execution, benchmarking, employee involvement, change management and the correct selection of continuous improvement tools and tactics. The three operations selected in the study were then evaluated against these elements through a survey, in order to gauge their alignment against each element.
The research found that none of the three operations met the ideal state of 85 per cent in aligning themselves to the six elements. Nampak Tubes was the only operation that came close to the required ideal level of 85 per cent, as the operation had re-implemented WCM in 2011 and as a result, the operations performance in terms of the selected KPIs was better than that of the other two. However, on average none of the three operations reached the 85 per cent ideal range. This was an indication that the PRs were not aligned to the required six elements in their attempt to implement WCM, and despite the three previous attempts, success had not been achieved.
The elements could prove complex as regards their comprehension and implementation as guided by the literature review and research, thus leadership should take careful note of the relationship between all of them. The organisational leadership is responsible for ensuring that the WCM strategy is driven centrally and adopted by all the stakeholders in the organisation, as all the elements require a leadership intervention.
World Class Manufacturing is more than a concept or a project; it is a philosophy which should be treated as a way of life, if organisations are to be successful in being competitive.
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Rodrigues, Monique Cordeiro. "Modelagem numérica de ligações viga-coluna em aço sob momento fletor e força normal." Universidade do Estado do Rio de Janeiro, 2009. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=5636.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>As ligações desempenham um papel fundamental no comportamento global das estruturas de aço. Inúmeros trabalhos de pesquisa têm sido desenvolvidos para entender o comportamento real de uma ligação e sua influência na resistência global dos pórticos. Atualmente, a Norma Brasileira de estruturas de aço de edificações, NBR 8800, considera o comportamento das ligações entre duas situações extremas: rígidas, onde não ocorre nenhuma rotação entre os membros conectados, transferindo momento fletor, força cortante e força normal; ou flexíveis, caracterizadas pela liberdade de rotação entre os membros conectados, impedindo a transmissão de momento fletor. Outras normas de projeto de estruturas de aço, consideram que as ligações apresentam um comportamento intermediário, ou seja, semi-rigídas, que podem estar submetidas a uma combinação de momento fletor e esforço normal. Porém, mesmo com a combinação, estas normas não consideram a presença de esforço normal (tração e/ou compressão). Uma limitação empírica de 5% da resistência plástica da viga é a única condição imposta no Eurocode 3. Para o estudo da ligação semi-rigída será utilizada a filosofia do Método das Componentes, que verifica a resistência da ligação e sua classificação quanto à rigidez rotacional, desenvolvida através de modelos mecânicos (modelos de molas). O objetivo deste trabalho é descrever alguns resultados de caracterização de ligações viga-coluna com placa de extremidade ajustada à altura da viga obtidos através de um modelo de elementos finitos. Para tal, será realizada uma análise não-linear geométrica e de material. Esta análise possibilitará avaliar os principais parâmetros que influenciam no comportamento deste componente no que diz respeito a sua avaliação em termos de distribuição de tensões e deformações no modelo de forma global.<br>The joints develop a fundamental role in the global behaviour of steel structures. Several researches are being developed to understand the real behaviour of a joint and its influence in the global frame capacity and beam-to-column joints of the steels buildings. Nowadays, the Brazilian Code of the Steel Portal Frame Design, NBR 8800, considers the joint behaviour between two extreme situations: rigid, where any rotations dont occur between the connected members, transfering substantial bending moments, and also shear and axial forces; or pinned, its characterised by almost free rotation movement between the connected elements that prevents the transmission of bending moments. However, some actual codes of the steel structures project, consider that the joints present an intermediate behaviour, in other words, semi-rigid, that may be subjected to a combination of bending moment and axial force. But, these codes dont consider the presence of axial force (tension and/ or compression). A single empirical limitation of 5% of the beams plastic axial capacity is the only enforced provision in Eurocode 3. This filosofy design is based on components method, for joint capacity evaluation and its classification concerning the joint rotation stiffness. This component method is based on mechanical models (spring model) created by an association of rigids and flexible joints components represented by a translacional spring. The objective of this present work is describing some results of flush endplate semi-rigids beam-to-column joints obtained across finite elements method and geometric and material non-linear analises. These consider the main parameters that influence the components behaviour about the stress and deformation distribution.
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Jacobsson, Madeleine. "Dr. Eleine Mad." Thesis, Kungl. Konsthögskolan, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kkh:diva-587.
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Dr. Eleine Mad är Madeleine Jacobsssons talesperson för dom vetenskapliga och paranormala upptäckter som uppstår i hennes världar. Hon beskriver innehåll, teknik och estetik utifrån ett kategoriseringssytem där konsten delas upp som olika typer av komponenter och därefter avkodas dessa allteftersom. För att förstå intuitionens inblandning i arbetsprocessen omförvandlas den till tre separata roller av en Sökare, Samlare och Myntare. Med rollerna försöker jag beskriva på vilka sätt som intuitionen är till gagn eller av förödelse för det konstnärliga arbetet. Sagan om M handlar om en grodlik karaktär, Delop, som lämnar sin hemplanet för att uppsöka andra världar. I sitt sökande hittar Delop ett folkslag vars syn och levnadssätt skiljer sig från hennes erfarenheter av “verkligheten” såsom hon lärt sig att överleva i den.<br>Dr. Eleine Mad is Madeleine Jacobsson's spokesperson for the scientific and paranormal discoveries that arise in her worlds. She describes content, tecniques and aesthetics based on a categorization system where art is divided into different types of components and then decoded as they go. To understand the intuition's involvement in the work process, it is transformed into three separate roles by a Seeker, Collector and a Myntare(In swedish language the one who is a "myntare" -is verbally declaring a concept or term). With these roles I try to describe in what ways intuition is beneficial or devastating to the artistic work. The story of M is about a frog-like character, Delop, who leaves the home planet to seek out other worlds. In her search, Delop finds a world whose views and lifestyles differ from her experiences of "reality" as she learned to survive in it.<br><p>Recorded sound and image material of the presentation is available for private use.</p>
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陳銘村. "Studies on the cold nosing processes by the rigid-plastic and elasto-plastic finite element method." Thesis, 1987. http://ndltd.ncl.edu.tw/handle/08194550319892014592.
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Kao, Wei-Chen, and 高偉程. "The study of rigid-plastic boundaries approach to 3-D rolling." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/60113087698346044525.
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Sandberg, Gary. "Indicators of bacterial lethality in semi-rigid plastic food containers during thermal processing." Thesis, 1999. http://hdl.handle.net/2429/10120.
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Thermocouple methods which have been used traditionally for gathering time-temperature data
for agitated retort processes have some physical limitations in that thermocouples located in the
centres of containers cannot accurately simulate free-moving particles. For this reason alternative
approaches have been taken to measure, understand and model such thermal processes, and this
was the purpose of the research carried out in these studies.
Thermal diffusivity was determined for a potato/alginate gel in order to detemiine the thermal
characteristics of the gel and thereby ascertain its ability to function as a model food particle.
Thermal diffusivity was found to average 2.048 x 10⁻⁷ m²/s, which approximates values reported in
the literature for potatoes (ranging from 1.64 x10⁻⁷ m²/s to 1.93 x 10⁻⁷ m²/s). Visualisation based
on video recording of 307 diameter plastic OMNI® bowls containing four food-simulating
particles were conducted in a Lagarde steam/air retort simulator to evaluate the effect of rotation on
particle movement. The speed of rotation was 2.8 rpm and particles were found to remain in
contact with the outer edge of the container near its lowest point, thus confirming that the principal
force acting on the particles is gravitational and not centrifugal. As well, a thin-wire (flexible)
thermocouple anchored in the centre of a spherical particle was evaluated as a method of gathering
time-temperature data while simulating the movement of free particles. The tethered particle was
found to be constrained to rotation in an arc from the top inner surface of the container to the
bottom inner surface.
Thermal processing studies were carried out during agitated processes in order to investigate
heating of 307 diameter plastic OMNI® bowls within a production-scale Lagarde steam/air retort.
at various rotational speeds (0, 5, 10, and 15 rpm). Since the goal was to understand processes
under production conditions, and since evidence of radial positional effects had been described for
the Lagarde steam/air retort simulator, the degree of positional effect was investigated. Bowls
positioned at the axial centre and the outside edge heated faster than bowls positioned in the
intermediate portion of the retort basket. The zone of slower heating was thought to be due to
the annular disc in the door which served to increase heating medium velocity down the outside
edges of the retort vessel and assist in its subsequent drawing back towards the fan through the
centre. Experiments were then repeated in the Lagarde retort simulator at 0, 5, 10, 15, 20 and 25
rpm to determine whether equivalent patterns were observed. Studies in the Lagarde were carried
out with rigid thermocouples and flexible thermocouples with their sensing junctions in
potato/alginate gel particles to determine if the flexible thermocouple gave a better model of the
temperature history within a freely moving particle in random motion during heating. Positional
effects were determined under static and rotational modes. Flexible thermocouples were found to
yield lower values for jh , fn and te than the rigid thermocouple.
A further stage of this research was aimed at assessing the effects of rotational thermal
processes on populations of microorganisms. Suspensions of Bacillus stearothermophilus ATCC
7953 were placed into DSC pans, hermetically sealed and incorporated into the centres of
potato/alginate particles (18 mm in diameter). Five such particles were placed into a 307 diameter
OMNI® bowl container and processed in the Lagarde steam/air retort simulator. Positional effects
were determined as well as rotational effects at 0, 15 and 30 rpm. Studies were done with particles
immobilised on rigid thermocouples positioned at the centres of containers as well as on flexible
probes (to simulate a flexible thermocouple). Within each small volume of the DSC pans,
integrated sterilisation (IS) values were determined, based on spore recovery from free particles,
particles with centrally located thermocouples and flexible thermocouples, and the liquid portion of
the product. With flexibly anchored and freely moving particles there was close agreement for IS
values, while for the rigidly held particles and the liquid contents of the container there was close
agreement for IS values.
A final study made use of the thermal indicator concept with Clostridium pasteurianum,
Bacillus coagulans, and lysozyme to evaluate pasteurisation of tomato-based sauces compared
to traditional temperature history methods. Three container sizes were used (3.8 L and 1.9 L
plastic jugs and a 750 mL glass jar). Measured lethalities were found to be greater than
calculated lethalities for all containers.
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林智銘. "Rigid plastic finite element analysis of ring compression and nonuniform thickness tube upsetting process." Thesis, 1987. http://ndltd.ncl.edu.tw/handle/40124006941207690561.
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Hung, Chen-Chieh, and 洪振傑. "The central bursting defects analysis of conical axisymmetric extrusion by rigid-plastic boundary approach." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/13478480832000095164.
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Chang, Cheng-Sung, and 張正松. "The study of rigid-plastic boundaries approach to analyze the arbitrary dies in axisymmetric extrusion." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/39813377203581682676.
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Dhirendra, V. K. "A Study Of Mixed-Mode Crack Growth In Elastic-Plastic Solids And Along Ductile-Rigid Interfaces." Thesis, 1996. http://etd.iisc.ernet.in/handle/2005/1696.
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TSAO, CHIH-WEI, and 曹志偉. "The study of rigid-plastic boundaries approach to analyze the quartic dies stress in axisymmetric extrusion." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/79148513493162057250.
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碩士<br>國立臺灣海洋大學<br>輪機工程系<br>94<br>A theoretical model to analyze quartic profiles of extrusion dies is proposed in this paper. In this model, the generalized rigid-plastic boundaries with quartic variables are used to minimize the power by the upper-bound method. To satisfy the velocity boundary conditions at entrance and exit, the streamline function is designed in the normal form of , which satisfies the flow conditions and the rigid-plastic boundaries. Used to the stress parameter to minimize the error of the equilibrium stress equation. This paper were conducted to compare with the results of the literature. It is found that the predicted load and flow patterns and stress field are in close agreement with the experimental observation versus the results from the literature.
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Duarte, Diogo Fernando Pedrosa. "Logoplaste-What are the opportunities in the European dairy industry?" Master's thesis, 2013. http://hdl.handle.net/10362/17551.
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Field lab: Entrepreneurial and innovative ventures<br>This paper studies the internationalization process of Logoplaste in the Rigid Plastic Container Industry, within the Dairy Products Industry. The conception of the implementation strategy required the study of the potential markets and its successful Business Model, derived from its internationalization experience. From all the European countries, Poland met the required conditions and was selected as the one with highest potential. Within Poland, the existent opportunities and the most efficient strategies to follow were addressed, with the entrance in the Yogurts Market being the main recommended tactical decision, as well as the continuity of Logoplaste best practices.
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Rodrigues, João Maria Dias. "Logoplaste : a market development strategy in the United Kingdom." Master's thesis, 2015. http://hdl.handle.net/10400.14/18796.
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Logoplaste is a leading private Portuguese company that has been manufacturing rigid plastic packaging solutions since 1976, triggered by the lack of capacity of the Portuguese market to offer quality solutions. Behind the success of the company is its business model the so-called “Hole in the wall”. By the end of 2014, the company was already present in 17 countries in 4 different continents. In the company future strategic approach, two main markets are under focus, namely the UK and the US. The goal is clear and ambitious, based on a proactive investment, within 5 years to double its operation in these markets.
The following case study based on the a deep analysis of the rigid plastic packaging industry, a close look over its business model and aiming to fulfill Logoplaste growth strategy in the UK market, suggests that Logoplaste should engage in an M&A transaction.
In line with the reasoning, six potential companies were identified. An extensive analysis of the six companies would be extremely time consuming and involve a high degree of resources allocation by Logoplaste. Consequently the identification of the selection criteria and its appliance in order to restrain the number of companies analyzed it is surely the next step to be done.<br>A Logoplaste é uma empresa portuguesa que está presente na manufactura de embalagens de plástico rígido desde 1976, despoletada pela falta de capacidade do mercado português de oferecer soluções de qualidade. Por trás do sucesso da empresa está o seu modelo de negócio, conhecido por “Hole in the wall”. No final de 2014 a empresa já tinha presença em 17 países em 4 continentes diferentes. Na sua abordagem estratégica para o futuro, dois mercados principais estão referenciados, nomeadamente o Reino Unido e os Estados Unidos. O objectivo é claro e ambicioso, baseado num investimento pró-activo duplicar as suas operações nestes mercados dentro de cinco anos.
O caso de estudo apresentado de seguida, baseado numa profunda análise da indústria da manufactura do plástico rígido, numa compreensão aprofundada do seu modelo de negócios e tendo em conta o objectivo estratégico de crescimento da Logoplaste no mercado do Reino Unido, sugere que esta deve adoptar por fusões e aquisições. De acordo com este raciocínio seis potenciais empresas foram identificadas. Uma análise exaustiva destas seis empresas por parte da Logoplaste envolveria um grande dispêndio de tempo e uma grande alocação de recursos. Consequentemente a identificação dos critérios de selecção e a sua aplicação, de forma a restringir o número de empresas analisádas será certamente a próxima accão a ser tomada.
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Lin, Sin-Yeh, and 林希彥. "Effect of The Rigd-Plastic Boundary on Upper-Bound Solution of rod Extrusion through Curved Dies." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/47947824225064170308.
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