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Evropské národy v komiksové sérii o Asterixovi / European nations in the Asterix seriesKozoňová, Zuzana January 2016 (has links)
The aim of the thesis is to confront predominantly Celtic nations depicted in the comic series about Aste rix by René Goscinny and Albert Uderz with information derived from literary as well as archaeological sources and consequently to describe current stereotypes and political and social events appearing in the series. Since its origin, Asterix series has become a world phenomenon with readers across both the social and age spectrum. Numerous allusions to the recent past, which the authors decided to humorously comment on through their cartoon characters, can be found in the series. However, each of the stories takes place in the historical background of the times around the year 50 BC, and it seems interesting to observe to what extent Uderzo and Goscinny stick to the sources and when their fantasy takes over. Keywords: Asterix, René Goscinny, Albert Uderzo, phenomenon, Celtic nations, ancient times, the Gauls, the Belgae, the Picts, the present nations, international
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Leveransledtidsreduktionens påverkan på finansiell prestanda : - En studie i tidens tecken / Implications of delivery lead-time reduction on financial performance : - A study in timeAugustsson, Kristoffer, Boldt, Simon January 2017 (has links)
Purpose: The study aimed to investigate how a delivery lead-time reduction impacts returnon-investment (ROI), and through the study create a decision support that quantitatively demonstrates the impact of the delivery lead-time reduction on manufacturing companies' ROI. To fulfill the purpose of the study two research questions were created: How is ROI affected by a delivery lead-time reduction? How can the impact of the delivery lead-time reduction on ROI be quantified? Method: A literature review was conducted to explain how a delivery lead-time reduction affects the ROI components. The literature review formed the theoretical framework, from which a proposition was created. With the proposition as a basis, a case study of one-case-design was carried out. The data for the first research question was collected through interviews with respondents from the focal company's market and production departments. The collected data was then pattern matched against the proposition, to develop the proposition. The answer from the first research question was then used as a basis for the quantification of the impact of the delivery lead-time reduction on ROI. During the empirical collection, there were limitations in data availability, therefore fictitious data was estimated to carry out the quantification and fulfill the second research question. Results: The study shows that there are many ways in which ROI can be affected by a delivery lead-time reduction, depending on the context, the starting point, and the approach in which the reduction is implemented. Therefore, an 8-scenario typology was created for how a delivery lead reduction can be implemented based on the six strategic lead times (SLT). Research question 1 shows, based on the data and the proposition, how delivery lead-time reduction impacts ROI in the typology’s scenario 7. Scenario 7 means a reduction in delivery lead-time, along with a reduction of the supply lead-time by reducing the external lead-time. The quantification of fictitious data, which answered the second research question, showed that it is possible to quantify the effect of the delivery lead-time reduction on ROI. Based on the approach of quantification, a decision support for investment in delivery lead-time reduction was created. Implications: The study contributes to the opportunity for practitioners to evaluate investment in delivery lead-time reduction, against other investment candidates, to strengthen the company's competitiveness. Theoretically, the study contributes with the typology for how a delivery lead-time reduction can be implemented. Also, a contribution through the proposition which shows how a delivery lead-time reduction generally affects ROI, versus the developed proposition that shows the influence based on scenario 7. Limitations: The quantification was based on fictitious data, which gave a limited result. Although it’s not the result of itself that is of interest, it is the logic of quantification, since the purpose is to develop a decision support. Also, the study is of one-case-design, whereupon the developed proposition cannot be applied on other companies without scrutiny and compared with their specific contexts. / Syfte: Studien syftade till att undersöka hur det finansiella prestandamåttet return on investment (ROI) påverkas vid en leveransledtidreduktion och genom studien skapa ett beslutsstöd som kvantitativt påvisar leveransledtidsreduktionens påverkan på tillverkandeföretags ROI. För att uppnå studiens syfte upprättades två forskningsfrågor: Hur påverkas ROI av en leveransledtidsreduktion? Hur kan leveransledtidsreduktionens påverkan på ROI kvantifieras? Metod: En litteraturgenomgång genomfördes för att förklara hur ROI komponenter påverkas av en leveransledtidsreduktion. Litteraturen sammanställdes sedan i en teoretisk referensram, utifrån vilken en proposition skapades. Med propositionen som grund utfördes en fallstudie av enfallsdesign. Empiri till den första forskningsfrågan samlades in genom intervjuer med respondenter från marknads- och produktionsavdelningen på fallföretaget. Empirin mönsterpassades mot den framtagna propositionen, som genom mönsterpassningen utvecklades. Svaret från första forskningsfrågan användes sedan som grund för kvantifieringen av leveransledtidsreduktionens påverkan på ROI. Under empiriinsamlingen visade det sig finnas begränsningar i tillgängliga data, varpå fiktiva data uppskattades för att kunna genomföra kvantifieringen och besvara andra forskningsfrågan. Resultat: Studien visade att det finns många olika sätt som ROI kan påverkas vid en leveransledtidsreduktion beroende på kontexten, utgångsläget och tillvägagångssättet som reduktionen genomförs i. Därför skapades en typologi med 8 scenarios för hur en leveransledtidsreduktion kan genomföras utifrån de sex strategiska ledtiderna (SLT). Forskningsfråga 1 visar utifrån empirin och propositionen påverkan på ROI vid scenario 7 i typologin. Scenario 7 innebär en reduktion av leveransledtiden och försörjningsledtiden genom att reducera den externa ledtiden. Kvantifieringen med fiktiva data påvisade att det är möjligt att kvantifiera leveransledtidsreduktionens påverkan på ROI. Utifrån tillvägagångssättet av kvantifieringen skapades ett beslutsstöd för investering i leveransledtidsreduktion. Implikationer: Studien bidrar till praktikers möjlighet att utvärdera en investering i leveransledtidsreduktion mot andra investeringskandidater för att stärka företags konkurrenskraft. Teoretiskt bidrar studien med typologin över hur en leveransledtidsreduktion kan genomföras. Även genom propositionen som visar hur en leveransledtidsreduktion påverkar ROI generellt, kontra den utvecklade propositionen som visar påverkan utifrån scenario 7. Begränsningar: Kvantifieringen baserades på fiktiva data vilket gav ett begränsat resultat. Det var istället logiken i kvantifieringen som var intressant, eftersom syftet var att utveckla ett beslutsstöd. Studien är en enfallsstudie, varpå den utvecklade propositionen inte kan appliceras för andra företag utan granskning och jämförelse med deras specifika kontexter.
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For the people : an appraisal comparison of imagined communities in letters to two South African newspapersSmith, Jade January 2013 (has links)
This thesis reports on the bonds that unify imagined communities (Anderson 1983) that are created in 40 letters prominently displayed on the opinions pages of the Daily Sun, a popular tabloid, and The Times, a daily offshoot of the mainstream national Sunday Times. An APPRAISAL analysis of these letters reveals how the imagined communities attempt to align their audiences around distinctive couplings of interpersonal and ideational meaning. Such couplings represent the bonds around which community identities are co-constructed through affiliation and are evidence of the shared feelings that unite the communities of readership. Inferences drawn from this APPRAISAL information allow for a comparison of the natures of the two communities in terms of how they view their agency and group cohesion. Central to the analysis and interpretation of the data is the letters’ evaluative prosody, traced in order to determine the polarity of readers’ stances over four weeks. Asymmetrical prosodies are construed as pointing to the validity of ‘linguistic ventriloquism’, a term whose definition is refined and used as a diagnostic for whether the newspapers use their readers’ letters to promote their own stances on controversial matters. Principal findings show that both communities affiliate around the value of education, and dissatisfaction with the country’s political leaders, however The Times’ readers are more individualistic than the Daily Sun’s community members, who are concerned with the wellbeing of the group. The analysis highlights limitations to the application of the APPRAISAL framework, the value of subjectivity in the analytical process, and adds a new dimension to South African media studies, as it provides linguistic insights into the construction of imagined communities of newspaper readership.
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Metascheduling of HPC Jobs in Day-Ahead Electricity MarketsMurali, Prakash January 2014 (has links) (PDF)
High performance grid computing is a key enabler of large scale collaborative computational science. With the promise of exascale computing, high performance grid systems are expected to incur electricity bills that grow super-linearly over time. In order to achieve cost effectiveness in these systems, it is essential for the scheduling algorithms to exploit electricity price variations, both in space and time, that are prevalent in the dynamic electricity price markets. Typically, a job submission in the batch queues used in these systems incurs a variable queue waiting time before the resources necessary for its execution become available. In variably-priced electricity markets, the electricity prices fluctuate over discrete intervals of time. Hence, the electricity prices incurred during a job execution will depend on the start and end time of the job.
Our thesis consists of two parts. In the first part, we develop a method to predict the start and end time of a job at each system in the grid. In batch queue systems, similar jobs which arrive during similar system queue and processor states, experience similar queue waiting times. We have developed an adaptive algorithm for the prediction of queue waiting times on a parallel system based on spatial clustering of the history of job submissions at the system. We represent each job as a point in a feature space using the job characteristics, queue state and the state of the compute nodes at the time of job submission. For each incoming job, we use an adaptive distance function, which assigns a real valued distance to each history job submission based on its similarity to the incoming job. Using a spatial clustering algorithm and a simple empirical characterization of the system states, we identify an appropriate prediction model for the job from among standard deviation minimization method, ridge regression and k-weighted average. We have evaluated our adaptive prediction framework using historical production workload traces of many supercomputer systems with varying system and job characteristics, including two Top500 systems. Across workloads, our predictions result in up to 22% reduction in the average absolute error and up to 56% reduction in the percentage prediction errors over existing techniques. To predict the execution time of a job, we use a simple model based on the estimate of job runtime provided by the user at the time of job submission.
In the second part of the thesis, we have developed a metascheduling algorithm that schedules jobs to the individual batch systems of a grid, to reduce both the electricity prices for the systems and response times for the users. We formulate the metascheduling problem as a Minimum Cost Maximum Flow problem and leverage execution period and electricity price predictions to accurately estimate the cost of job execution at a system. The network simplex algorithm is used to minimize the response time and electricity cost of job execution using an appropriate flow network. Using trace based simulation with real and synthetic workload traces, and real electricity price data sets, we demonstrate our approach on two currently operational grids, XSEDE and NorduGrid. Our experimental setup collectively constitute more than 433K processors spread across 58 compute systems in 17 geographically distributed locations. Experiments show that our approach simultaneously optimizes the total electricity cost and the average response time of the grid, without being unfair to users of the local batch systems. Considering that currently operational HPC systems budget millions of dollars for annual operational costs, our approach which can save $167K in annual electricity bills, compared to a baseline strategy, for one of the grids in our test suite with over 76000 cores, is very relevant for reducing grid operational costs in the coming years.
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Management of technology in the process industries: Matching market and machineSamuelsson, Peter January 2017 (has links)
The process industries span multiple industrial sectors and constitute a substantial part of the entire manufacturing industry. Since companies belonging to this family of industries are often very asset intensive, their ability to respond to changes is often limited in the short term. The adaptation of the capabilities of existing processes, and conversely finding products and market segments to match the production system capabilities, are an important part of product- and market development activities in the process industry. The importance to companies in the process industry of having a well-articulated manufacturing strategy congruent with the business strategy is second to none. However, to facilitate manufacturing strategy developments, it is essential to start with an improved characterization and understanding of the material transformation system. To that end an extensive set of variables was developed and related measures and scales were defined. The resulting configuration model, focusing on company generic process capabilities in the process industries, is to be regarded as a conceptual taxonomy and as a proposition available for further testing. The usability of the model was subsequently assessed using “mini-cases” in the forestry industry, where the respondents confirmed that the company’s overall strategy could benefit from this kind of platform as a possible avenue to follow. The model was deployed as an instrument in the profiling of company material transformation systems to facilitate the further development of companies' functional and business strategies. The use of company-generic production capabilities was studied in three case companies representing the mineral, food and steel industries. The model was found by the respondents to be usable as a knowledge platform to develop production strategies. In the final analysis of the research results, a new concept emerged called “production capability configuration": A process-industrial company’s alignment of its generic production capabilities in the areas of raw materials, process technology and products to improve the consistency among the variable elements that define operations and improve the congruence between operations and its environment. From the perspective of value creation and capture, firms must be able to manufacture products in a competitive cost structure within the framework of a proper business model. By using the configuration model, the relationship between manufacturing and innovation activities has been studied in the previously mentioned three case studies. In many cases the gap in capability appears as a limitation in the production system, requiring development efforts and sometimes investments to overcome. This is illustrated with two examples from the steel industry, where development efforts of the production system capabilities are initiated to better match the market demands. One example is the increase the volume- and product flexibility of an existing stainless steel melt shop, resulting in a proposed oblong Argon Oxygen Decarburisation (AOD) converter configuration that was subsequently verified using water modelling. The second example is from a carbon steel mill, where the target was to increase the raw material- and volume flexibility of another melt shop, by modifying the capabilities of the Electric Arc Furnace (EAF). Enabling EAF technologies are further described and evaluated using operational data and engineering type of estimates. / <p>QC 20170116</p>
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Epidemia de Malária no Ceará: enredos de vidas, mortes e sentidos políticos (1937-1942)SILVA, Gláubia Cristiane Arruda 13 August 2012 (has links)
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Previous issue date: 2012-08-13 / Os estudos e as pesquisas históricas acerca das doenças constituem-se em caminhos por meio dos quais é possível construir novas perspectivas de análise das sociedades em tempos e espaços diversos. Essa tese de doutorado acerca da epidemia de malária, ocorrida entre os anos de 1937 e 1942, tem como um dos seus enfoques centrais a análise de como a população dos municípios localizados na área denominada Baixo Jaguaribe, no estado do Ceará, vivenciou este surto epidêmico. Outro caminho perseguido foi o de analisar os momentos em que a malária deixava de ser apenas um problema do indivíduo, da família e tornava-se alvo de políticas públicas dos governos municipal, estadual e federal, além disso, passavam também a ser negociadas com uma instituição dos EUA, a Fundação Rockefeller. Dessa forma, outro foco de análise foramas ações empreendidas pelo governo municipal, estadual, federal e pela Fundação Rockefeller nas tentativas de erradicar o mosquito transmissor da doença, Anopheles gambiae,através, por exemplo, de campanhas como o Serviço de Obras Contra a Malária (SOCM) e, posteriormente, pelo Serviço de Malária do Nordeste (SMNE). E, por fim, outra dimensão pesquisada e analisada nessa tese foram as relações estabelecidas entre os moradores locais eum saber institucionalizado pela ciência no combate a doença, confrontando, assim, os tratamentos e os saberes daquela população. / Studies andhistorical researchconcerning thediseases arepathsthrough whichone canbuild newperspectives on society’s analysisindifferenttimes and places. Thisdoctorate thesison themalaria epidemic, which occurred between1937 and1942,has asone of itscentralfocusesthe analysison how thepopulation of the municipalitieslocatedin the area calledBaixo Jaguaribein the state ofCeará,experiencedthisoutbreak. Anotherpath pursuedwas to analyzethe moments in whichmalariawas no longerjust a problem ofthe individual or its familyand becamethe target ofpublic policiesof municipal,state and federal government, also beingnegotiated withaU.S. institution, the Rockefeller Foundation.Thus, another focus of the present analysis was the actions taken by the municipal, state and federal government, and the Rockefeller Foundation in attempts to eradicate the mosquito that transmits the disease, Anopheles gambiae, through, for example, the campaigns such as the Serviço de Obras Contra a Malária (SOCM) and later by theServiço de Malária do Nordeste (SMNE). Finally, another dimension researched and analyzed in this thesis was the relation between local residents and a scientific institutionalized knowledge to fight the disease, thus comparing the treatments and knowledge of that population.
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The Distributed and Assembly Scheduling ProblemHatami, Sara 16 May 2016 (has links)
[EN] Nowadays, manufacturing systems meet different new global challenges and
the existence of a collaborative manufacturing environment is essential to face
with. Distributed manufacturing and assembly systems are two manufacturing
systems which allow industries to deal with some of these challenges. This
thesis studies a production problem in which both distributed manufacturing
and assembly systems are considered. Although distributed manufacturing
systems and assembly systems are well-known problems and have been extensively
studied in the literature, to the best of our knowledge, considering
these two systems together as in this thesis is the first effort in the literature.
Due to the importance of scheduling optimization on production performance,
some different ways to optimize the scheduling of the considered problem are
discussed in this thesis.
The studied scheduling setting consists of two stages: A production and an
assembly stage. Various production centers make the first stage. Each of these
centers consists of several machines which are dedicated to manufacture jobs.
A single assembly machine is considered for the second stage. The produced
jobs are assembled on the assembly machine to form final products through a
defined assembly program.
In this thesis, two different problems regarding two different production
configurations for the production centers of the first stage are considered.
The first configuration is a flowshop that results in what we refer to as the
Distributed Assembly Permutation Flowshop Scheduling Problem (DAPFSP).
The second problem is referred to as the Distributed Parallel Machine and
Assembly Scheduling Problem (DPMASP), where unrelated parallel machines
configure the production centers. Makespan minimization of the product on the
assembly machine located in the assembly stage is considered as the objective
function for all considered problems.
In this thesis some extensions are considered for the studied problems
so as to bring them as close as possible to the reality of production shops.
In the DAPFSP, sequence dependent setup times are added for machines in
both production and assembly stages. Similarly, in the DPMASP, due to
technological constraints, some defined jobs can be processed only in certain
factories.
Mathematical models are presented as an exact solution for some of the
presented problems and two state-of-art solvers, CPLEX and GUROBI are
used to solve them. Since these solvers are not able to solve large sized
problems, we design and develop heuristic methods to solve the problems. In
addition to heuristics, some metaheuristics are also designed and proposed to
improve the solutions obtained by heuristics. Finally, for each proposed problem,
the performance of the proposed solution methods is compared through
extensive computational and comprehensive ANOVA statistical analysis. / [ES] Los sistemas de producción se enfrentan a retos globales en los que el concepto
de fabricación colaborativa es crucial para poder tener éxito en el entorno
cambiante y complejo en el que nos encontramos. Una característica de los sistemas
productivos que puede ayudar a lograr este objetivo consiste en disponer
de una red de fabricación distribuida en la que los productos se fabriquen en
localizaciones diferentes y se vayan ensamblando para obtener el producto
final. En estos casos, disponer de modelos y herramientas para mejorar el
rendimiento de sistemas de producción distribuidos con ensamblajes es una
manera de asegurar la eficiencia de los mismos.
En esta tesis doctoral se estudian los sistemas de fabricación distribuidos
con operaciones de ensamblaje. Los sistemas distribuidos y los sistemas con
operaciones de ensamblaje han sido estudiados por separado en la literatura.
De hecho, no se han encontrado estudios de sistemas con ambas características
consideradas de forma conjunta.
Dada la complejidad de considerar conjuntamente ambos tipos de sistemas
a la hora de realizar la programación de la producción en los mismos, se ha
abordado su estudio considerando un modelo bietápico en la que en la primera
etapa se consideran las operaciones de producción y en la segunda se plantean
las operaciones de ensamblaje.
Dependiendo de la configuración de la primera etapa se han estudiado dos
variantes. En la primera variante se asume que la etapa de producción está
compuesta por sendos sistemas tipo flowshop en los que se fabrican los componentes
que se ensamblan en la segunda etapa (Distributed Assembly Permutation
Flowshop Scheduling Problem o DAPFSP). En la segunda variante
se considera un sistema de máquinas en paralelo no relacionadas (Distributed
Parallel Machine and Assembly Scheduling Problem o DPMASP). En ambas
variantes se optimiza la fecha de finalización del último trabajo secuenciado
(Cmax) y se contempla la posibilidad que existan tiempos de cambio (setup)
dependientes de la secuencia de trabajos fabricada. También, en el caso
DPMASP se estudia la posibilidad de prohibir o no el uso de determinadas
máquinas de la etapa de producción.
Se han desarrollado modelos matemáticos para resolver algunas de las
variantes anteriores. Estos modelos se han resuelto mediante los programas
CPLEX y GUROBI en aquellos casos que ha sido posible. Para las instancias
en los que el modelo matemático no ofrecía una solución al problema se han
desarrollado heurísticas y metaheurísticas para ello.
Todos los procedimientos anteriores han sido estudiados para determinar
el rendimiento de los diferentes algoritmos planteados. Para ello se ha realizado
un exhaustivo estudio computacional en el que se han aplicado técnicas
ANOVA.
Los resultados obtenidos en la tesis permiten avanzar en la comprensión
del comportamiento de los sistemas productivos distribuidos con ensamblajes,
definiendo algoritmos que permiten obtener buenas soluciones a este tipo de
problemas tan complejos que aparecen tantas veces en la realidad industrial. / [CAT] Els sistemes de producció s'enfronten a reptes globals en què el concepte de
fabricació col.laborativa és crucial per a poder tindre èxit en l'entorn canviant
i complex en què ens trobem. Una característica dels sistemes productius
que pot ajudar a aconseguir este objectiu consistix a disposar d'una xarxa de
fabricació distribuïda en la que els productes es fabriquen en localitzacions
diferents i es vagen acoblant per a obtindre el producte final. En estos casos,
disposar de models i ferramentes per a millorar el rendiment de sistemes de
producció distribuïts amb acoblaments és una manera d'assegurar l'eficiència
dels mateixos.
En esta tesi doctoral s'estudien els sistemes de fabricació distribuïts amb
operacions d'acoblament. Els sistemes distribuïts i els sistemes amb operacions
d'acoblament han sigut estudiats per separat en la literatura però, en allò
que es coneix, no s'han trobat estudis de sistemes amb ambdós característiques
conjuntament. Donada la complexitat de considerar conjuntament ambdós
tipus de sistemes a l'hora de realitzar la programació de la producció en els
mateixos, s'ha abordat el seu estudi considerant un model bietàpic en la que
en la primera etapa es consideren les operacions de producció i en la segona es
plantegen les operacions d'acoblament.
Depenent de la configuració de la primera etapa s'han estudiat dos variants.
En la primera variant s'assumix que l'etapa de producció està composta per
sengles sistemes tipus flowshop en els que es fabriquen els components que
s'acoblen en la segona etapa (Distributed Assembly Permutation Flowshop
Scheduling Problem o DAPFSP). En la segona variant es considera un sistema
de màquines en paral.lel no relacionades (Distributed Parallel Machine and
Assembly Scheduling Problem o DPMASP). En ambdós variants s'optimitza
la data de finalització de l'últim treball seqüenciat (Cmax) i es contempla la
possibilitat que existisquen temps de canvi (setup) dependents de la seqüència
de treballs fabricada. També, en el cas DPMASP s'estudia la possibilitat de
prohibir o no l'ús de determinades màquines de l'etapa de producció.
S'han desenvolupat models matemàtics per a resoldre algunes de les variants
anteriors. Estos models s'han resolt per mitjà dels programes CPLEX
i GUROBI en aquells casos que ha sigut possible. Per a les instàncies en
què el model matemàtic no oferia una solució al problema s'han desenrotllat
heurístiques i metaheurísticas per a això. Tots els procediments anteriors han
sigut estudiats per a determinar el rendiment dels diferents algoritmes plantejats.
Per a això s'ha realitzat un exhaustiu estudi computacional en què s'han
aplicat tècniques ANOVA.
Els resultats obtinguts en la tesi permeten avançar en la comprensió del
comportament dels sistemes productius distribuïts amb acoblaments, definint
algoritmes que permeten obtindre bones solucions a este tipus de problemes
tan complexos que apareixen tantes vegades en la realitat industrial. / Hatami, S. (2016). The Distributed and Assembly Scheduling Problem [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/64072 / TESIS
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Upscaling nonreactive solute transportLlerar Meza, Gerónimo 29 June 2009 (has links)
This thesis focuses on solute transport upscaling. Upscaling of solute transport is usually required to obtain computationally efficient numerical models in many field applications such as, remediation of aquifers, environmental risk to groundwater resources or the design of underground repositories of nuclear waste. The non-Fickian behavior observed in the field, and manifested by peaked concentration profiles with pronounced tailing, has questioned the use of the classical advection-dispersion equation to simulate solute transport at field scale using numerical models with discretizations that cannot capture the field heterogeneity. In this context, we have investigated the use of the advection-dispersion equation with mass transfer as a tool for upscaling solute transport in a general numerical modeling framework.
Solute transport by groundwater is very much affected by the presence of high and low water velocity zones, where the contaminant can be channelized or stagnant. These contrasting water velocity zones disappear in the upscaled model as soon as the scale of discretization is larger that the size of these zones. We propose, for the modeling solute transport at large scales, a phenomenological model based on the concept of memory functions, which are used to represent the unresolved processes taking place within each homogenized block in the numerical models.
We propose a new method to estimate equivalent blocks, for which transport and mass transfer parameters have to be provided. The new upscaling technique consists in replacing each heterogeneous block by a homogeneous one in which the parameters associated to a memory functions are used to represent the unresolved mass exchange between highly mobile and less mobile zones occurring within the block. Flow upscaling is based on the Simple Laplacian with skin, whereas transport upscaling is based in the estimation of macrodispersion and mass transfer parameters as a result of the interpretation of the r / Llerar Meza, G. (2009). Upscaling nonreactive solute transport [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/5848 / Palancia
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Increasing the efficiency level of loading operation in a fuel distribution plantAnticona Lizama, Leslie Sofía, Medina Yzquierdo, Eylin Fabiana 05 July 2020 (has links)
Este artículo tiene como objetivo solucionar el problema de ineficiencia, representado por el bajo nivel de servicio en el sistema de distribución de la planta de combustible, ya que se han presentado retrasos desde el inicio del proceso hasta el final de este. Por este motivo, se analizó todo el flujo del sistema para determinar en qué parte del proceso estaba la causa principal, lo que ayudaría a reducir considerablemente el problema. Se propuso aplicar un sistema de citas para estandarizar los tiempos de servicio, así como la implementación de un algoritmo y el uso de mecanismos eficientes para derivar la mejor solución robusta que responda a todas las incertidumbres con tiempos de ejecución reducidos. / This article aims to solve the inefficiency problem, represented by the low service level, in the fuel plant distribution system, since there have been delays from the beginning of the process to the end of this. For this reason, the entire flow of the system was analyzed in order to determine where in the process the main cause was, which would help reduce this problem considerably. It was proposed to apply an appointment system to standardize service times as well as the implementation of an algorithm and the use of efficient mechanisms to derive the best robust solution that responds to all uncertainties with reduced execution times. / Trabajo de investigación
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Framing and Sourcing Dynamics in Trauma Coverage: PTSD in The New York Times, 1999–2020Long, Aaron T. 10 September 2021 (has links)
No description available.
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