Orientador: Edison Bittencourt / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-02T10:43:10Z (GMT). No. of bitstreams: 1 Oriani_LuisAlbertodeGodoy_D.pdf: 16939728 bytes, checksum: c76f77e44418dacbca2dd6acbbe6f55a (MD5) Previous issue date: 2001 / Resumo: As propriedades de terpolimeros de polietileno tereftalato (PET) são o objeto do presente estudo. A quantificação das propriedades relacionadas com o peso molecular e o teor dos comonõmeros, até então praticamente inexistente, foi realizada de forma inédita em literatura. O objetivo desse estudo é: a partir de 14 diferentes terpoHmeros de PET, quantificar as propriedades térmicas, de estiramento e a estrutura mOITológica formada durante a produção de garrafas (através do processo de estiramentosopro). Para caracterização térmica foi utilizada a técnica de calorimetria exploratória de varredura, tanto em análises isotérmicas como em não isotérmicas. O processamento dos polímeros foi feito através de: sopro em laboratório (sopro sem molde) e sopro em máquina industrial. Para caracterizar as garrafas e protogarrafas produzidas, utilizamos os seguintes aparelhos: coluna de gradiente de densidade (densidade aparente), picnõmetro de hélio e porosímetro de mercúrio (densidade absoluta), espectrõmetro de radiação infravermelha (cristalinidade e orientação), micrõmetro (espessura) e um medidor da taxa de permeação de oxigênio (através da parede de toda a embalagem). De forma geral, podemos dizer que a relação entre o peso molecular (Mn) e o teor de di-etileno glicol, rege grande parte das propriedades: térmicas (foi determinada a energia de ativação para cristalização durante resfriamento), de estiramento e a formação de estruturas porosas na parede da garrafa. Com respeito às propriedades de estiramento, o teor de DEG tem influência oposta ao peso molecular (Mn), mas com a mesma intensidade. Propomos um modelo morfológico para representar a parede de uma garrafa PET. Este modelo faz uma analogia entre a parede da garrafa e uma membrana assimétrica. Em ambos os casos, existe uma variação estrutural ao longo da espessura. Na garrafa, de um lado da parede, temos uma estrutura compacta e homogênea do outro lado uma estrutura porosa e com defeitos estruturais. O tamanho das estruturas formadas no interior da parede é função da temperatura de processamento e aparentemente independe da formulação do polímero. Pelos testes efetuados, a formação de poros e vazios estruturais na parede de uma garrafa, não é função somente das condições de processamento ou de quantos graus estamos acima da temperatura de transição vítrea. Aparentemente a composição do polímero, tem influência na tendência a formar poros. Observou-se ainda, uma forte interação entre peso molecular (Mn) e teor de DEG. Foram desenvolvidos dois tipos de análise especiais: uma que permite a visualização da permeabilidade ao oxigênio em regiões determinadas de uma garrafa sem que seja necessário destruí-Ias. Na outra, foi desenvolvida uma composição de corantes que permite revelar diferenças estruturais. Ambas as técnicas podem ser de grande valia em pesquisa e controle de produção de garrafas. Este estudo, por abranger diversos aspectos relacionados às propriedades de terpolímeros de PET , é de significativa importância em toda a cadeia de processamento desde a injeção de preformas, ao sopro de garrafas e as propriedades do produto final / Abstract: PET terpolymers properties were never determined in a complete way. quantification of the relationship between the molecular weight and the comonomers content is practically inexistent. The objective of that study is, starting from 14 different PET terpolymer types, to quantify the thermal properties of stretching and the morphologic structure formed during the blowing of bottles through the stretching-blow process. For the thermal characterization of the polymers, differential scanning calorimetry (DSC) was used, in isothermic analyses of dynamics the processing of polymers was made through blow in laboratory (blow without mold) and blow in industrial machine. For the characterization of the produced bottles, a density gradient column (apparent density), helium picnometry and mercury porosimetry (absolute density), infrared spectroscopy (cristalinity and orientation), thickness and oxygen permeation ratio through the overall packaging. In a general way, one can say that the molecular weight (Mn) I di-ethylene glycol ratio, governs great part of the thermal properties of stretching and of porosity, in the studied samples. The activation energy for crystallization during cooling was determined, DEG is an exact opposite to the molecular weight (Mn), for the properties of stretching of PET. A morphological model to represent the wall of a bottle PET was proposed. This model makes an analogy between the wall of the bottle and an asymmetrical membrane, In both cases, exists a structural variation along the thickness, In the bottle, on one side of the wall there is a compact and homogeneous structure on the other side a porous structure and with structural defects. The size of the structures formed inside the wall is function of the processing temperature and is apparently independent on the polymer formulation. The formation of pores and structural voids in the wall of a bottle due to the tests carried out, were not function only of the processing conditions or of how much above the glass transition temperature the material was. Apparently, the composition of the polymer itself has influence in its tendency to form pores. In this sense, there is a strong interaction between molecular weight (Mn) and tenor of DEG. Two special analysis types were developed. One of them allows the visualization of the permeability to the oxygen in certain areas of a bottle with no need to destroy the bottle. In the second technique it was developed a composition of colors that allows to reveal structural differences. 80th techniques can be valuable in research and control of production of bottles. For this study includes several aspects related to the properties of PET terpolimers, it is of significant importance in the whole processing chain, from the preforms injection, to the blow of bottles and the properties of the final product / Doutorado / Doutor em Engenharia Química

One recent innovation in the networking industry, is the concept of Network FunctionVirtualization (NFV). NFV is based on a networking paradigm in which network functions,which have typically been implemented in the form of dedicated hardware appliances in thepast, are implemented in software and deployed on commodity hardware using modernvirtualization techniques. While the most common approach is to place each virtual networkfunction in a virtual machine - using hardware-level virtualization – the growing influenceand popularity of Docker and other container-based solutions has naturally led to the idea ofcontainerized deployments. This is a promising concept, as containers (or operating systemlevel virtualization) can offer a flexible and lightweight alternative to hardware-levelvirtualization, with the ability to use the resources of the host directly. The main problem withthis concept, is the fact that the default behavior of Docker and similar technologies is to relyon the networking stack of the host, which typically isn’t performant enough to handle theperformance requirements associated with NFV. In this dissertation, an attempt is made toevaluate the feasibility of using userspace networking to accelerate the network performanceof Docker containers, bypassing the standard Linux networking stack by moving the packetprocessing into userspace.

To minimize the damage in the event of a security breach it is desirable to limit the privileges of remotely available services to the bare minimum and to isolate the individual services from the rest of the operating system. To achieve this there is a number of different containment strategies and process privilege security models that may be used. Two of these mechanisms are Solaris Containers (a.k.a. Solaris Zones) and Type Enforcement, as implemented in the Fedora distribution of Security Enhanced Linux (SELinux). This thesis compares how these technologies can be used to isolate a single service in the operating system. As these two technologies differ significantly we have examined how the isolation effect can be achieved in two separate experiments. In the Solaris experiments we show how the footprint of the installed zone can be reduced and how to minimize the runtime overhead associated with the zone. To demonstrate SELinux we create a deliberately flawed network daemon and show how this can be isolated by writing a SELinux policy. We demonstrate how both technologies can be used to achieve isolation for a single service. Differences between the two technologies become apparent when trying to run multiple instances of the same service where the SELinux implementation suffers from lack of namespace isolation. When using zones the administration work is the same regardless of the services running in the zone whereas SELinux requires a separate policy for each service. If a policy is not available from the operating system vendor the administrator needs to be familiar with the SELinux policy framework and create the policy from scratch. The overhead of the technologies is small and is not a critical factor for the scalability of a system using them.

The use of physical systems and Virtual Machines has become inefficient and expensive for creating tailored, hands-on exercises for providing cyber security training. The main purpose of this project is to directly address these issues faced in cyber security education with the help of Docker containers. Using Docker, a lightweight and automated platform was developed for creating, sharing, and managing hands-on exercises. With the help of orchestration tools, this platform provides a centralized point to monitor and control the systems and exercises with a high degree of automation. In a classroom/lab environment, this infrastructure enables instructors and students not only to share exercises but also helps create and deploy exercises more easily. By streamlining the end to end delivery and deployment of the exercises, instructors can now efficiently make use of the class/lab hours in educating the students rather than performing system administration tasks.

The goal of the thesis is to examine and assess actual portfolio of products on the market for server visualization and to compare performance of individual products with performance of the physical machine. The research and the assessment of the actual portfolio will be carried out with the focus on current trends in the area of server virtualization, reasons for realization, and important aspects for their successful implementation. The comparison will be carried out in areas of supported platforms, hardware emulation spectra, hardware limitations, licensing and prices. Further it will be performed comparison in the form of benchmark performance in areas of CPU, RAM, hard-drive throughput, and network throughput of most commonly used products for server virtualization.

The aim of the thesis is to characterize the folding containers as one of the potential solutions to the problem of the repositioning of empty containers and to evaluate the possibility of their practical use in intermodal transport. The theoretical part characterizes contemporary development in international trade, intermodal transportation, the issue of empty containers and also characterizes foldable containers together with the assumptions of their successful introduction to the market. The practical part deals with current concepts of foldable containers, there is also an example for comparing the costs of transport when using standard or foldable containers and the opinion of a representative of one of the leading shipping companies on use foldable containers in practice. To obtain information used in the practical part of the thesis a secondary research was carried out, where most information comes from research papers and websites, and also primary research was done in the form of an interview with a representative of the shipping company. In conclusion is the evaluation of the possibility of using foldable containers in practice which is based on the information obtained through research.

The object of this research was to develop a retort for research and development of thermal processes which use common commercial thermal processing techniques. An FMC 500W laboratory sterilizer, designed to operate with an FMC weir product racking system, was modified for conventional steam, positive flow steam/air and water immersion/air overpressure thermal processing of foods in thin profile retortable packages. The research included the modification of the retort plumbing and the fabrication of a set of product trays and a racking system. The completed system was tested for temperature distribution and stability, and heat transfer distribution for each processing mode. The latter was achieved by comparing the heat penetration parameters calculated from the centerpoint temperature histories of conduction heating teflon transducers. / Applied Science, Faculty of / Graduate

With the advent of virtualization and artificial intelligence, research on networked systems has progressed substantially. As the technology progresses, we expect a boom in not only the systems research but also in the network of systems domain. It is paramount that we understand and develop methodologies to connect and communicate among the plethora of devices and systems that exist today. One such area is mobile ad-hoc and space communication, which further complicates the task of networking due to myriad of environmental and physical conditions. Developing and testing such systems is an important step considering the large investment required to build such gigantic communication arrangements. We address two important aspects of network emulation in this work. We propose a network emulation framework, which emulates the functioning of a hierarchical software defined network. One such use-case is described using a mobile ad-hoc network (MANET) topology within a single system by leveraging contemporary network virtualization technologies. We present various aspects of the network, such as the dynamic communication in the software domain and provide a novel approach to build upon existing emulation techniques. The second part of the thesis presents a dynamic network link emulator. This emulator enables suitable link property re-configurations such as bandwidth, delay and packet loss for networked systems using simulation software. We characterize the results of tests for the link emulation using a hardware and software testbed. Through this thesis, we aim to make a small yet crucial contribution to the niche area of software defined networks.

Background:  Cloud computing technology has come a long way with various technological advancements in the past few years. It has been accelerated with the evolution of various virtualization technologies. Currently almost every social platform and small-scale applications look towards cloud to deploy their services successfully and provide maximum satisfaction to their end-user. Thus, virtualizing their services becomes utmost important to deploy and develop their applications. This alone emphasizes the importance of Docker containers in the development world. Docker containers right now are playing a very important role in the field of cloud computing. Since Multimedia plays a huge role in our day to day lives and most people crave for faster and efficient responses, it is essential to develop our applications with better Real time communication capabilities. Thus, we are determining which container orchestration tool serves best for Real time communication applications.  A multimedia application is developed and deployed using WebRTC based Kurento media server and the performance of the server is measured when the application is deployed. We have chosen Kubernetes and Docker Swarm as container platforms for this thesis. The Servers and Clients are virtualized and metrics such as CPU Utilization, Network Traffic, Container overhead, Memory Utilization are measured. These metrics provide the performance overhead in different scenarios for each orchestration technology. This will be helpful to analyze and understand the effect of Kurento server on these technologies. Thus, the results are expected to determine which orchestration technology serves best for RTC applications. Objectives: The objectives of this project are:  • To implement WebRTC based Kurento server in a container orchestrated environment.  • To extract performance metrics such as Network Traffic, CPU and Memory Utilization while server is running.  • To compare WebRTC based Kurento server in Kubernetes and Docker Swarm.   Method: Kubernetes and Docker Swarm environments are setup and then docker images with video conferencing application(One-to-One call and One-to-Many call) using Kurento media server is deployed in them. Once either of the applications is running, experiments are performed for analyzing performance metrics like CPU Utilization, Memory Utilization, Network Traffic and overhead using monitoring tool, Prometheus. Along with Kubernetes and Docker Swarm, Kurento server is also deployed on a stand-alone container to estimate the performance overhead. Later, statistical analysis(ANOVA and differences of Standard error) is done over these metrics and conclusions are drawn.  Results: Based on the performed experiments and the extracted metrics, for One-to-One call application, Kubernetes showed better resource utilization for CPU and Network Traffic while it consumed more memory over Docker Swarm. Similar behaviour is observed for One-to-Many application. When application is scaled, the percent of resource utilization increase in Kubernetes is higher when compared to Docker Swarm, but overall resource utilization of Kubernetes is much lower than that of Docker Swarm.  Conclusions: WebRTC based Kurento media server is investigated in  Kubernetes and Docker Swarm. From the detailed analysis there is significant overhead in Docker Swarm than in Kubernetes for CPU Utilization and Network Traffic. For Memory Utilization, this is opposite. Packet Loss resulted in 0 percent as network transfer is within the same network . By considering all the metrics and providing evidence that numbers obtained in this thesis are statistically significant and not by fluctuations(ANOVA and post-hoc analysis), we can better recommend Kubernetes over Docker Swarm for Web based Real Time Communication.   However, not all applications need the complex deployment, scheduling, and scaling services (or the overhead) that Kubernetes offers. But to meet the increasing demand for seamless Real time communications, and to suffice user requirements, the overheard offered by it is acceptable.

Cieľom tejto práce je navrhnúť službu pre automatizované testovanie študentských programovacích projektov na základe požiadaviek a následne implementovať túto službu za použitia technológií OpenShift, Python a Git. Vytvorenie takejto služby stavia základ pre zjednotený proces testovania študentských projektov, ktorý zahŕňa spúšťanie testovacích sád v oddelených Linuxových kontajneroch. Vylepšený testovací proces má viesť ku zjednodušeniu známkovania vyučujúcimi a taktiež zlepšeniu výsledkov študentov pri týchto úlohách.   Táto diplomová práca vysvetľuje základy testovania softvéru, pričom sa sústredí na testovanie založené na požiadavkách, poskytuje náhľad do technológie kontajnerov a objasňuje, ako boli tieto témy zahrnuté pri návrhu služby a taktiež, ako sa ich použitie odrazilo na požiadavkách na ňu. Okrem toho je implementácia tejto služby podrobená detailnej analýze, ktorá má slúžiť ako referenčný materiál pre jej akékoľvek budúce rozšírenia.   Implementovaná služba je schopná vykonávať základné operácie, zahřňajúce paralelné testovanie študentských projektov v oddelených kontajneroch, vytvorenie kontajnerizovaného ladiaceho prostredia, alebo automatické zostavenie kontajnerového obrazu pre konkrétne zadanie.