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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Load-response and the effect of de-bonding on structural insulated panels performance

Delijani, Farhoud 21 June 2016 (has links)
Series of full-scale tests were conducted on polyurethane foam-core Structural Insulated Panels (PUR SIPs) to study the load response and creep behavior of such panels. The load response of PUR SIPs was compared with conventional stud wall panels. The effects of de-bonding between the foam-core and the OSB face-sheets were also studied to understand the effects of such change on the overall performance of PUR SIPs. At last, computer modelling was employed to simulate and predict the behavior of PUR SIPs in different loading orientations and dis-bond ratios. It was found that PUR SIPs can outperform conventional stud-wall panels in every aspect. In the case of 165 mm (6.5 in.) thick PUR SIPs, 33% dis-bond between the PUR foam-core and the OSB face-sheets caused an average of 64% reduction in ‘axial load’ capacity, an average of 75.8% reduction in ‘transverse load’ capacity, and an average of 7.9% reduction in ‘racking load’ capacity of the panels compared to brand new fully-bonded SIPs. It was also found that 33% dis-bond in 165 mm (6.5 in.) thick PUR SIPs has minimal effect on the racking load capacity of the panels. In the case of 114 mm (4.5 in.) thick PUR SIPs, 33% dis-bond be-tween the PUR foam-core and the OSB face-sheets caused an average of 63.3% reduction in ‘axial load’ capacity, an average of 79% reduction in ‘transverse load’ capacity, and an average of 29% increase in ‘racking load’ capacity of the panels compared to brand new fully-bonded SIPs. All tested panels satisfied the code requirements for the creep deflections (span/180) and they fully rebounded to their initial estate, 90 days after removal of the simulated snow loads. It was also found that weathering has minimal effect on the bond between the face-sheets and the PUR foam. After computer simulations of fully-bonded and dis-bonded PUR SIPs in two different thicknesses, it was found that SOLIDWORKS simulation software is a useful tool to predict the load response of PUR SIPs only when fully-bonded panels are exposed to transverse load orientation regardless of the thickness of the panel. In general, available Canadian and American standards were followed in this study. Where applicable, standards were adopted from other material testing methods for testing PUR SIPs. It is believed that this independent research has addressed most frequently ex-pressed concerns regarding the use and application of structural insulated panels such as de-bonding issues and creep behavior and their relationship to durability. The hope is that is research help increase the use and application of SIPs in green, high-performance, light-frame building construction in Canada. / October 2016
2

Modelling human ageing: role of telomeres in stress-induced premature senescence and design of anti-ageing strategies

de Magalhães, João Pedro 16 January 2004 (has links)
Due to the duration of human ageing, researchers must rely on models such as animals and cells. Replicative senescence and stress-induced premature senescence (SIPS) are two cellular models sharing many features. Although telomeres play a major role in replicative senescence, their involvement in SIPS is unclear. In this work, we first wanted to investigate how accurate models of ageing are. We published a new model of the evolution of human ageing, which offers a refined view of the evolution of ageing in humans and suggests that human models should be favoured. Though studying other mammals, reptiles, and birds may also be useful, we conclude that lower life forms such as yeast and invertebrates are not representative of the human ageing process. Secondly, we wanted to elucidate the importance of telomeres in SIPS and study gene expression and regulatory networks. Using a telomerase-immortalized cell line, we found no evidence that damage specific to the telomeres is at the origin of SIPS. In our published model, neither the TGF-â1 pathway nor telomeres appear to play a crucial role in SIPS. We suggest that widespread damage to the DNA causes SIPS and propose a rearrangement of gene expression networks as a result of stress. Moreover, we advise caution in using telomerase in anti-ageing therapies since telomerase expression may alter the normal cellular functions and promote tumorogenesis. Lastly, we published strategies to integrate the modern computational approaches to research ageing. Although we find it unlikely that a full understanding of ageing may be achieved within a near future, we argue that understanding the structure and finding key regulatory genes of the human ageing process is possible.
3

Analýza platobných systémov v Českej a Slovenskej republike / Analysis of payment systems in the Czech republic and Slovak republic

Molnárová, Lucia January 2011 (has links)
This thesis analyses the interbank payment systems in the Czech republic and Slovak republic. First chapter includes the definitions and basic characteristics of payment system and payment services. Both analysed countries are members of the European Union, next chapter so defines its payment systems and their legislation background, with the focus on TARGET2 system. Chapter 3 and 4 concentrate on characteristics of Czech and Slovak payment systems from different points of view. In Slovakia, there are two payment systems, large-value system TARGET2-SK and retail system SIPS. In Czech Republic operates only one payment system CERTIS for both types of transactions. The last and main part of thesis is devoted to detailed analysis of statistical data for these payment systems concerning the period from 2006 to 2011.
4

Vindstabilisering av SIPS byggnader i Sverige / Wind Stabilization of SIPS buildings in Sweden

Esmael, Hasani, Johan, Maniea January 2023 (has links)
This work is about wind stabilization of a SIPS building in Sweden where the focus is onhow joints take place between the foundation plate and the walls. SIPS (Structural insulatedpanels) is a load-bearing insulation element used to build the entire building envelope. It is anewly arrived building technology in Sweden that is used for passive houses in order toreduce energy use. The elements are prefabricated and bonded together with fiberglassbeams, which are also used to reinforce openings in the building. The method that will beused in this work is the finite element method using a computer program FEM-design by thecompany Strusoft. In the programme the model was rebuilt and calculated according to theEurocode. In collaboration with SIP's company Avis Building technology, the building andthe joint were modeled according to one of their buildings, which was then analyzed. Thisresulted in the joint consisting of screws attached to a profile of aluminum. The result gavethe shear and normal forces that affect the screw and plat. In this way, the question of how anattachment of a SIPs building can take place has been answered. The results in FEM-designshow that a SIPS building can be wind-stabilized in Sweden with the exception of certainparts that can be supplemented with a load-bearing inner wall to achieve full stabilization.But this question cannot be answered with complete certainty without more data and researchon the element being. Too many parameters about the properties of the elements wereunknown, which led to uncertainty. In the program, the building was stabilized but had toolarge deformations in some places. This does not mean that such a building cannot bestabilised, but more research must be carried out before the conclusion can be drawn. In thework, no tests were made of the element, which contributed to this uncertainty. With moremeasurements and trials, a SIPS building can definitely become a future building technologyin Sweden.
5

Improving Ozone SIP Modeling in Complex Terrain at a Fine Grid Resolution

Kim, Yunhee 01 May 2010 (has links)
Meteorological variables such as temperature, wind speed, wind directions, and Planetary Boundary Layer (PBL) heights have critical implications for air quality simulations. Sensitivity simulations with five different PBL schemes associated with three different Land Surface Models (LSMs) were conducted to examine the impact of meteorological variables on the predicted ozone concentrations using the Community Multiscale Air Quality (CMAQ) version 4.5 with local perspective. Additionally, the nudging analysis for winds was adopted with three different coefficients to improve the wind fields in the complex terrain at 4-km grid resolution. The simulations focused on complex terrain having valley and mountain areas for ozone SIPs (State Implementation Plans). The ETA M-Y (Mellor-Yamada) and G-S (Gayno-Seaman) PBL schemes were identified as favorite options and promote O3 formation causing the higher temperature, slower winds, and lower mixing height among sensitivity simulations in the area of study. It was found that PX simulation did not always give optimal meteorological and CMAQ model performances at mountain sites. The results of nudging analysis for winds with three different increased coefficients’ values (2.5, 4.5, and 6.0 x 10-4 per second) over seven sensitivity simulations show that the meteorological model performance was enhanced due to improved wind fields, indicating the FDDA (Four Dimensional Data Assimilation) nudging analysis can improve model performance considerably at 4-km grid resolution. Specifically, the sensitivity simulations with the coefficient value (6.0 x 10–4) yielded more substantial improvements than with the other values (2.5 and 4.5 x 10-4). Hence, choosing the nudging coefficient of 6.0 x 10-4 per second for winds in MM5 may be the best choice to improve wind fields as an input, as well as, better model performance of CMAQ in the complex terrain area. The sensitivity of RRFs (Relative Response Factors) to the PBL scheme may be considerably significant with about 1-3 ppb in difference in determining whether the attainment test is passed or failed. Finally, a finer grid resolution was necessary to evaluate and access of CMAQ results for giving a detailed representation of meteorological and chemical processes in the regulatory modeling.
6

Investigation of Sediment Ridges Using Bathymetry and Backscatter near Clearwater, Florida

Stewart, Lewis 29 November 2017 (has links)
Changes in sediment morphology on the West Florida Shelf is investigated over a 14-year time period using multibeam bathymetry and backscatter in water depths between 10 m and 20 m, off the coast of Indian Rocks Beach, Pinellas County, Florida. Bathymetric surveys collected in 2002 (Kongsberg EM 3000 at 300 kHz) and 2016 (Reson 7125 at 400 kHz) were processed using CARIS Hips and Sips to create bathymetric maps and backscatter images. These data were then interpreted and compared in order to test hypotheses and answer questions related to sediment migration and sediment volume change. The following questions prompted this study: A. How mobile is the sediment on the limestone? B. What sedimentary changes occurred following the 2002 and 2003 deployments of mines for an Office of Naval Research project? C. How much sediment was removed during dredging and how closely does it compare to the Army Corps of Engineers’ reported estimate during the beach renourishment of Sand Key in 2012? In order to answer these questions, hypotheses were proposed: Hypothesis A: The sediment ridges in the study site have not migrated significantly over the limestone hard bottom during the 14-year time period (Hafen, 2001; Edwards et al. 2003). Hypothesis B: There is no change in sediment volume where the mine-like object were placed and removed after the ONR mine burial experiment (Wolfson 2005 Wolfson et al. 2007). Hypothesis C: Changes in sediment volume between 2002 and 2016 will match the amount estimated by the Army Core of Engineers who dredged the area. Results show that the sediment ridges in the study area had some migration over the limestone hard bottom during the 14-year time period. The results also found that there was a sediment volume change where mine-like objects were placed and removed during the Office of Naval Research mine burial experiment because of a dredging operation in 2012 that dredged sediment from the experimental area. Specific areas investigated that surround the dredging area showed significant loss of sediment, with the change in hydrodynamics from dredging influencing this sediment loss. The volume of sediment removed from the aforementioned dredging cut was found to be within 16% of that estimated in the Army Corps of Engineers report prior to the dredging. Geologic interpretations of the backscatter images interpreted strong backscatter returns as limestone, mid strength returns as coarse shell hash and weak returns as fine to medium-grained sediments. The weak returns were found primarily on the sediment ridges. The dredging cut showed stronger returns than the surrounding ridge, indicating that underlying coarse sediments were most likely compacted and composed of shell hash. Using satellite remote sensing as a way to gather continual repeat coverage at high resolution (2 m) data to determine absolute depth in these water depths is investigated and preliminary results suggest that processed 250 m pixel MERIS data will give a similar depth range as multibeam bathymetry. The higher-resolution 0.5 m pixel raw WorldView 2 data shows NW-SE trending structure, suggesting the seafloor morphology will be more visible.
7

Vindstabilisering av SIPS byggnader i Sverige / Wind Stabilization of SIPS buildings in Sweden

Hasani, Esmael, Maniea, Johan January 2023 (has links)
Detta arbete handlar om vindstabilisering av en SIPS byggnad i Sverige där fokuset ligger påhur infästningar sker mellan grundplattan och väggarna. SIPS (Structural insulated panels) ärett bärande isoleringselement som används för att bygga hela byggnadskalet. Det är ennykommen byggnadsteknik i Sverige som används för passivhus för att kunna minskaenergianvändningen enligt Parisavtalet. Elementen är prefabricerade och binds ihop medglasfiberbalkar, som även används för att förstärka öppningar i byggnaden (dörrar ochfönster). Metoden som kommer att användas i detta arbete är finita elementmetoden medhjälp av datorprogrammet FEM-design av företaget Strusoft. I programmet återuppbyggdesmodellen som analyserade byggnaden enligt finita elementmetoden och beräknade medhänsyn till Eurokod. I samarbete med SIPs företaget Avis Building technology modelleradesbyggnaden och skarven enligt en modul från företaget, där resultatet sedan analyserades.Detta resulterade skarven består av skruvar som fästs i en Z-profil som binder ihop väggenmed grunden. Resultatet gav de skjuv-och normalkrafter som skruven och plåten utsätts för.Dessa krafter analyserades och på så sätt kunde en lämplig leverantör hittas som tillverkarskruvar som kan ta upp dessa laster. Valet landade på Zebra Pias (hexagonal head withcollar) av företaget WÜRTH. Denna metod användes även för att hitta en leverantör somtillverkar passande profiler som kan hantera lasterna utan att gå i brott. Valet landade påaluminiumprofiler med tjockleken 4 mm av företaget Tibnor. På så sätt har frågeställningenom hur en infästning av SIPs-byggnad kan ske blivit besvarad. Resultaten i FEM-designvisar att en SIPS-byggnad kan vindsatbiliseras i Sverige med undantag vissa delar som kankompletteras med en bärande innervägg för att nå full stabilisering. Men denna frågeställningkan inte besvaras med full säkerhet utan att mer data och forskning om elementet görs. Alltför många parametrar om elementens egenskaper var okända vilket ledde till en osäkerhet. Iprogrammet var byggnaden stabiliserad men hade för stora deformationer på vissa ställen.Detta betyder inte att en sådan byggnad inte kan stabiliseras, utan fler undersökningar måstegöras innan slutsatsen kan dras. I arbetet gjordes inga prövningar av elementet vilket bidrogtill denna osäkerhet. Vid fler mätningar och prövningar kan en SIPS-byggnad absolut bli enframtida byggnadsteknik i Sverige.
8

Modeling VOCs Emissions from Multi-layered Structural Insulated Panels(SIPs)

Yuan, Huali 21 October 2005 (has links)
Indoor air quality is recognized as one of the most important environmental concerns, since people spend almost 90% of their lifetime indoors. Indoor sources of volatile organic compounds (VOCs) are a determinant of air quality in houses. Many materials used to construct and finish the interiors of new houses emit VOCs. These emissions are a probable cause of acute health effects and discomfort among occupants. Ventilation is another determinant of indoor air quality in houses, because it serves as the primary mechanism for removal of gaseous contaminants generated indoors. Thus, higher contaminant concentrations are expected at lower ventilation rates given constant emission rates. The trend in new construction is to make house envelopes tighter for higher energy efficiency. The use of Structural Insulated Panels (SIPs) in new construction and major renovation to create very tight building envelopes is one popular approach to realizing this goal. The basic SIPs configuration uses oriented strand board (OSB) and polystyrene foam (PSF) in a multi-layered sandwich-like structure. Specific benefits of SIPs include lower energy consumption, stronger more durable structures and better resource efficiency. These advantages make panelized systems very attractive from both environmental impact and energy use perspectives. However, there is a potential for houses constructed with SIPs to have degraded air quality relative to conventionally constructed houses that utilize fewer engineered wood products. OSB emits pentanal and hexanal, two odorous aldehydes. These contaminants originate in the wood drying process through the breakdown of wood tissue and are, thus, inherent to most engineered wood products. The PSF in SIPs is a major source of styrene. The large surface area of installed SIPs systems (typically the entire exterior shell), combined with the resulting decrease in ventilation rate due to very low infiltration, exacerbates the indoor air problem. Thus, the potential release of volatile contaminants must be taken into careful consideration when designing homes constructed with SIPs. The ability to predict and ultimately minimize the negative impact of panel systems on indoor concentrations of contaminants of concern would be extremely useful for advancing housing technologies. No prior investigations of VOC emissions from SIPs have been reported in the literature. Two main methods are used to characterize emissions from building materials: chamber studies and mathematical modeling. While chamber studies are costly and time-consuming, mathematical modeling is becoming an economical and effective alternative. Physically-based models are especially useful because they provide insight into the governing mechanisms and the factors that control the emissions process. Although emissions from building materials have traditionally been empirically characterized in chambers, we have recently validated a mechanistic model that predicts VOC emissions from vinyl flooring. The approach involved independently measuring C0 (the initial material-phase concentration), D (the material-phase diffusion coefficient), K (the material/air partition coefficient) and then predicting the emission rate a priori using a fundamental mass-transfer model We now wish to generalize this approach and use it to predict emissions from multi-layered SIPs. To begin with, we will apply a single-layer model to predict emissions from each of the two SIP components: OSB and PSF. Once this has been accomplished, it should be possible to develop a multi-layer model to predict emissions from the composite SIPs. Our first research objective was to characterize transport of volatile organic compounds (VOCs) in polystyrene foam (PSF), a diffusion-controlled building material. The sorption/desorption behavior of the polystyrene foam was investigated using a single-component system. A microbalance was used to measure the sorption/desorption kinetics and to obtain equilibrium relationships. Hexanal and styrene were selected as the target compounds. While styrene transport in PSF can be described by Fickian diffusion with a symmetrical and reversible sorption/desorption process, the hexanal transport process exhibited significant hysteresis, with desorption being much slower than sorption. To address this hysteresis, a porous media diffusion model that assumes local equilibrium governed by a non-linear Freundlich isotherm was developed. The model was found to conform closely to the experimental kinetic data for both sorption and desorption. By incorporating the Freundlich sorption mechanism into the traditional Fickian diffusion model, the hysteresis in the hexanal transport process in PSF was explained. Contaminant emissions from building materials may tail extensively and require longer times to desorb than absorb. This slow desorption or hysteresis problem has been an obstacle to understanding VOC emissions from building materials. The overall goal of our second research objective was to (i) develop a predictive nonlinear emission model by incorporating a local Freundlich sorption equilibrium to account for the slow desorption; (ii) validate the new nonlinear emission model using independent chamber data; and (iii) compare the new nonlinear emission model with a previously published linear emission model. Styrene in polystyrene foam (PSF) and hexanal in oriented strand board (OSB) were selected as the target compounds and materials, respectively. Sorption/desorption kinetic experimental data show that while styrene sorption/desorption in PSF is symmetrical, hexanal sorption/desorption in OSB is not symmetrical. For hexanal in OSB, slower desorption was observed. Model validation results show that while the simple linear emission model can predict styrene emissions from PSF, it underestimates hexanal emissions from OSB. With the new nonlinear emission model developed in this research, hexanal emission from OSB can be predicted. These results suggest that local sorption equilibrium needs to be considered when predicting the emission rate of polar compounds from building materials. The final objective was to develop a new multi-layer model for a layered SIP system. Composite layered building materials are widely used in indoor environments due to their environmental and energy advantages. However, the tight structure may result in degraded indoor air quality and the potential release of volatile organic compounds (VOCs) from these layered materials must be considered. A theoretical physically-based diffusion model for predicting VOCs emissions from such multi-layer materials is described in this research. It is assumed that the individual layers are flat homogeneous slabs, that internal mass transfer is governed by diffusion, and that the indoor air is well mixed. For each layer, the material-phase diffusion coefficient (D), the material-phase partition coefficient (K), and the initial material-phase concentration (C0) are the key model parameters. In this model, fugacity is used to numerically solve the model because this eliminates the discontinuities in concentration at the interface between layers. This overcomes an insurmountable obstacle associated with numerically simulating mass transfer in composite layers. The fugacity-based numerical model is checked by comparing predicted concentrations to those obtained with a previously published analytical model for double-layered materials. In addition, transport of hexanal and styrene within, and emissions of hexanal and styrene from, multi-layer Structural Insulated Panels (SIPs) are simulated to demonstrate the usefulness of the model. These preliminary results establish the viability of the fugacity approach. Finally, the multi-layer layer model is used to demonstrate the impact that barrier materials can have. Results show that contaminant gas phase concentration can be reduced greatly with a barrier layer on the surface. This deomonstrates the potential of thin barrier layers to minimize the environmental impact of panelized systems. Future work will focus on a more complete experimental validation of the multi-layer model. / Ph. D.
9

The fire performance of engineered timber products and systems

Hopkin, Danny James January 2011 (has links)
Timber is an inherently sustainable material which is important for future construction in the UK. In recent years many developments have been made in relation to timber technology and construction products. As the industry continues to look to construct more efficient, cost effective and sustainable buildings a number of new engineered timber products have emerged which are principally manufactured off-site. In terms of light timber frame, products such as structural insulated panels (SIPs) and engineered floor joists have emerged. For heavy timber construction, systems such as glulam and cross laminated timber (CLT) are now increasingly common. Despite many of the obvious benefits of using wood as a construction material a number of concerns still exist relating to behaviour in fire. Current fire design procedures are still reliant upon fire resistance testing and 'deemed to satisfy' rules of thumb. Understanding of 'true' fire performance and thus rational design for fire resistance requires experience of real fires. Such experience, either gathered from real fire events or large fire tests, is increasingly used to provide the knowledge required to undertake 'performance based designs' which consider both fire behaviour and holistic structural response. At present performance based structural fire design is largely limited to steel structures and less frequently concrete buildings. Many of the designs undertaken are in accordance with relevant Eurocodes which give guidance on the structural fire design for different materials. For the same approaches to be adopted for timber buildings a number of barriers need to be overcome. Engineered timber products, such as SIPs and engineered joists, are innovative technologies. However, their uptake in the UK construction market is increasing year on year. Little is known about how such systems behave in real fires. As a result the development of design rules for fire is a difficult task as failure modes are not well understood. To overcome this barrier the author has undertaken a number of laboratory and natural fire tests on SIPs and engineered floor joists to establish how such products behave and fail in real fires. The data gathered can be used to develop design approaches for engineered timber products in fire, thus negating the need to rely upon fire resistance testing. The development of design rules from the data gathered would be a progressive step towards performance based design. Realising performance based fire design for timber structures at present has three obvious barriers. Firstly, thermo-physical properties for timber exposed to natural fires are not well defined. Current guidance in standards such as EN 1995-1-2 provides data for standard fire exposure only. Movement towards design for parametric fires requires a better understanding of timber thermo-physical behaviour under different rates of heating and durations of fire exposure. Secondly, particularly in the UK, the fire performance of timber buildings is heavily influenced by the behaviour of gypsum plasterboard which is commonly used as passive fire protection. The thermal behaviour of gypsum under both standard and natural fire conditions is still not well understood. The majority of research available relating to gypsum in fire is dated, whilst board products continually evolve. Finally, the whole building behaviour aspects utilised in the fire design of steel and other structures have arisen as a result of complex numerical simulations. At present most commercial finite element codes are not appropriate for modelling entire timber buildings exposed to fire due to complexities relating to the constitutive behaviour of timber. Timber degrades differently depending upon stress state (i.e. tension or compression), temperature and importantly temperature history. In recognition of the above barriers, the author has made a number of developments. Firstly, a modified conductivity model for softwood is proposed which is shown to give acceptable depth of char and temperature predictions in timber members exposed to the heating phase of parametric fires. This model is suitable for adoption in any computational heat transfer model. Secondly, the finite element software TNO DIANA has been modified, via user supplied subroutines, to simulate large timber buildings exposed to fire by considering stress state, temperature and state history. The developments made in this engineering doctorate are intended to facilitate the progression of performance based design for timber structures. The numerical approaches adopted herein have been supported using multi-scale experimental approaches. As a result a number of novel tools for implementation in FEA models are proposed which should ultimately lead to a more rational approach to the fire design of timber buildings.
10

A reverse proxy for VoIP : Or how to improve security in a ToIP network

Dhainaut, Guillaume January 2016 (has links)
The need for security is crucial in Telephony over IP (ToIP). Secure protocols have been designed as well as specific devices to fulfill that need. This master thesis examines one of such devices called Session Border Controller (SBC), which can be compared to reverse proxies for ToIP. The idea is to apply message filters to increase security. This thesis presents the reasons of SBC existence, based on the security weaknesse sa ToIP network can show. These reasons are then used to establish a list of features which can be expected from a SBC and discuss its ideal placement in a ToIP network architecture. A test methodology for SBCs is established and used on the free software Kamailio as an illustration. Following this test, improvements of this software, regarding threats prevention and attacks detection, are presented and implemented. / Behovet av säkerhet är av avgörande betydelse i telefoni över IP (ToIP). Säkerhetsprotokoll har utformats samt särskilda enheter för att uppfylla detta behov. Detta examensarbete undersöker en av sådana enheter som kallas Session Border Controller (SBC), vilket kan jämföras med omvända proxyservrar för ToIP. Tanken är att tillämpa meddelandefilter för att öka säkerheten. Denna avhandling presenterar orsakerna till SBC existens, baserat på de säkerhets svagheter en ToIP nätverk kan visa. Dessa skäl används sedan för att upprätta en förteckning över egenskaper som kan förväntas av en SBC och diskutera dess ideal placering i en ToIP nätverksarkitektur . En testmetodik för SBC är etablerad och används på fri programvara Kamailio som en illustration. Efter detta test, förbättringar av denna programvara, om hot förebyggande och attacker upptäcka, presenteras och genomförs.

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