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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

SDL-Datenkonzepte - Analyse und Verbesserungen

Schröder, Ralf. January 2003 (has links) (PDF)
Berlin, Humboldt-Universiẗat, Diss., 2003.
2

Students' Perceptions of Persistence in a Florida Associate Degree Nursing Program

Saith, Shivanie 01 January 2017 (has links)
At a community college in Florida, the associate of science in nursing (ASN) program has experienced low persistence rates especially after the first semester of study. Framed by Jeffreys's nursing undergraduate retention and success model, a mixed-method approach was used to investigate first-semester and final-year ASN students' perceptions of factors influencing persistence and successful persistence strategies. In the quantitative sequence, first-semester students (N = 95) completed the Student Perception Appraisal-Revised-2 (SPA-R2) survey measuring perceptions of 5 persistence factors (environmental, institutional integration, personal academic, college academic, and friend support persistence). ANOVA and t tests were conducted by age, gender, language, ethnicity, marital status, employment, and number of dependents to identify differences between students' perceptions of factors influencing persistence. Results showed that: for males, environmental and personal academic factors were significant; for those employed 1 to 10 hours, the institutional integration factor was significant; and for the 45 to 49 age group, all persistence factors were significant. In the qualitative sequence, final-year students (N = 12) were interviewed to understand the persistence factors that contributed to their success. Thematic analyses revealed that family, peer, and financial support, as well as employing strategies for study habit modification and personal motivation influenced students' persistence toward program completion. Findings were used to develop an online curriculum plan for incoming ASN students that includes training on study habits and encourages students to form support systems to promote students' program completion resulting in positive social change in the nursing community.
3

GS-MBE Growth of Ga(ln)AsN Nitrides for Long Wavelength Semiconductor Lasers

Yuan, Lixiang January 2000 (has links)
Quaternary GalnAsN containing a small amount of nitrogen (<2%) is a potentially promising material for realizing long-wavelength emission lasers for applications in optical communication systems. Such devices should have better high-temperature characteristics than conventional InGaAsP lasers due to an increase of the conduction band offset. In this thesis, the GS-MBE growth of quaternary GalnAsN and ternary GaAsN was carried out. Active N was produced by passing high purity nitrogen gas into either an RF or an ECR plasma source. The RF plasma source was found to produce better quality nitrides. Characterization techniques such as photoluminescence, X-ray diffraction, TEM, SIMS, and Hall effect measurements were used to characterize thick layers (e.g. 1 pm) and quantum wells of these nitride materials. The concentration of N incorporated into GalnAs and GaAs is very dependent on growth conditions and plasma conditions. The incorporation of a small amount of N into compressively strained InGaAs reduces the strain and produces a red-shift of photoluminescence peak. However, compared to N-free InGaAs materials, the optical quality is dramatically degraded yielding reduced photoluminescence intensity and a broadened FWHM of the PL peak. Hall effect measurements on un-doped, Si-doped, Bedoped thick GalnAsN layers indicate the presence of a high concentration of electron and hole traps. The results of SIMS suggest that impurity H might be responsible for the deep level defects formed. However, the nature of the defects is currently unknown. From TEM observations and comparison to samples grown with a He-plasma instead of a Nplasma, spinodal decomposition and ion-induced damage in GalnAsN may produce the reduced quality of materials, but these are not the major reasons responsible for the dramatic degradation of optical quality. Thermal annealing was found to be an effective method for significantly improving the optical quality of GalnAsN with a low N concentration. Optimum annealing conditions were obtained. Hall effect measurements on annealed samples indicate that electron and hole traps are reduced but still present after anneal. / Thesis / Master of Engineering (ME)
4

Molecular Beam Epitaxy of Ga(In)AsN/GaAs Quantum Wells towards 1.3µm and 1.55µm

Wang, S.Z., Yoon, Soon Fatt, Ng, Teck Khim, Loke, W.K., Fan, W.J. 01 1900 (has links)
In this article, we report an attempt of extending the InGaAsN materials towards 1.3µm and 1.55µm wavelength. All these InGaAsN samples are grown in a plasma-assisted solid-source molecular-beam epitaxy (SS-MBE) system. Our experiments revealed that the nitrides could be grown with both direct nitrogen beam and dispersive nitrogen. The nitrogen incorporation rate could be reduced by the presence of indium flux. The interaction between nitrogen and indium might lead to 3D growth mode and growth dynamics. It is proved that the increasing growth rate reduces the nitrogen incorporation efficiency. The data for nitrogen sticking coefficient are somewhat contradictive. The growth with dispersive nitrogen source causes the improvement of material quality. Fixed indium flux is a better way for the wavelength control. Also, we report some growth optimization work for better PL property and the annealing effect on the samples. Literature is sometimes reviewed for comparison. / Singapore-MIT Alliance (SMA)
5

Régulation de l’assimilation de l’azote minéral chez Arabidopsis en conditions de stress salin / Regulation of nitrogen assimilation in Arabidopsis under salt conditions

Maaroufi Dguimi, Houda 23 February 2012 (has links)
L’activité de croissance des plantes se trouve souvent limitée par les conditions contraignantes de l’environnement. La salinité du sol est l’une des majeures contraintes abiotiques qui ne cesse d’envahir les surfaces cultivés chaque année. Elle entraine chez les espèces glycophytes des perturbations d’ordre osmotique, nutritionnel et métaboliques. La nutrition et le métabolisme de l’azote minéral constituent des étapes primordiales dans la synthèse des acides aminés et des composés azotés indispensables chez les plantes. Par conséquent, l’étude de l’expression des enzymes impliquées dans l’assimilation d’azote telle que l’asparagine synthétase (AS, EC 6.3.5.4) chez l’arabette des dames (Arabidopsis thaliana) permet d’avancer nos connaissances sur la régulation transcriptionnelle du métabolisme azoté sous stress salin. Au cours des travaux de recherche entamés dans le cadre de cette thèse, un intérêt particulier est accordé au gène ASN2 chez Arabidopsis. Les résultats obtenus ont montré que la mutation ASN2 a accentué les effets du NaCl sur l’assimilation de l’ammonium. Le mutant asn2-1 se montre plus sensible au stress salin que le sauvage malgré que l’absence des transcrits du gène ASN2 est associé à une expression importante du gène ASN1. L’inhibition de l’activité glutamine synthétase (GS, EC 6.3.1.2), la faible activité aminatrice de la GDH (NADH-GDH, EC 1.4.1.2) sous stress salin ainsi que l’absence des transcrits ASN2 seraient à l’origine de l’accumulation de l’ammonium chez le mutant asn2-1. Toutefois, l’application exogène de l’ammonium nous a montré que l’action du NaCl sur l’expression de l’asparagine synthétase n’est pas directement liée à l’accumulation endogène d’ammonium. L’accumulation d’autres métabolites tels que l’asparagine, la glutamine et la glutamate pourrait être à l’origine des effets du sel sur l’expression des gènes ASN. / Plant growth activity is often limited by constraint environment conditions. Soil salinity is one of major abiotic stress which is becoming more problematic every year. In glycophytes species, it induced osmotic, nutritional and metabolic disturbances. The nitrogen nutrition and metabolism constitute an essential step in amino acid and nitrogen compounds synthesis in plants. Therefore, studying the expression of enzymes involved in nitrogen assimilation such as asparagine synthetase (AS, EC 6.3.5.4) in Arabidopsis thaliana will improve our knowledge on the transcriptional regulation of nitrogen metabolism under salt stress. In the present work of this thesis, a special attention was taken on AS gene (ASN2) wild type and mutants. Obtained results showed that ASN2 mutation accentuated the salt-induced effects on ammonium assimilation. The asn2-1 mutant was more sensitive to salt stress than the wild type, while the ASN2 transcript absence was associated with an important ASN1expression. The observed inhibition of glutamine synthetase (GS, EC 6.3.1.2) activity, the low aminatrice GDH (NADH-GDH, EC 1.4.1.2) activity under salt stress as well as the ASN2 transcript loss brought to an ammonium accumulation in asn2-1mutant. However, exogenous ammonium application showed that NaCl effect on asparagine synthetase expression was not directly related to the endogenous ammonium accumulation. Other metabolites accumulation such as asparagine, glutamine and glutamate could be involved in the obtained salt-effects on ASN expression in Arabidopsis.
6

SDL-Datenkonzepte

Schröder, Ralf 26 March 2003 (has links)
SDL in der 1996 standardisierten Sprachversion ist zur Zeit die im Telekommunikationsbereich am weitesten verbreitete Sprache zur Spezifikation von Protokollen. Ein wesentlicher Aspekt der Sprachentwicklung seit 1988 ist auch die Verfügbarkeit einer formalen Basis semantischer Konzepte. Für das Datenkonzept der Sprache wurde auf die algebraischen Technik ACT ONE zurückgegriffen. Obwohl Anspruch als auch praktischer Wert von SDL in der Ausführbarkeit als Spezifikationstechnik liegt, wird dieses gerade durch das verwendete Datenmodell beeinträchtigt. Verdeckt wird dieses Problem durch die Bereitstellung von vordefinierten Datentypen. Durch die Erweiterung von SDL um objektorientierte Konzepte im Jahr 1992 und durch die allgemein wachsende Bedeutung der Daten in Protokollbeschreibungen treten die vorhandenen Sprachprobleme bei den Daten immer mehr in der Vordergrund. Individuelle Lösungen zur Spezifikation von Daten in verfügbaren SDL-Werkzeugen sind die Folge. In der vorliegenden Arbeit werden sowohl die praxismotivierten Unzulänglichkeiten als auch die formalen Unstimmigkeiten im SDL-Datenkonzept aufgezeigt. Auf der Grundlage einer systematischen Analyse werden ein allgemeiner Anforderungskatalog und eine Methodik für Veränderungen am Datenkonzept erarbeitet. Zusätzlich werden wichtige Sprachmodifikationen mit dem Schwerpunkten Ausdruckskraft und Ausführbarkeit vorgestellt und bewertet. Es steht somit ein Instrumentarium zur Verfügung, das den unterschiedlichen SDL-Interessengruppen bei der Bewertung und Nutzung von SDL-Veränderungen dienlich ist. Die in der Arbeit vorgestellten Modifikationen des Datenkonzepts basieren auf den langjährigen Erfahrungen des Autors bei der Implementierung und dem Einsatz von Werkzeugen, die mit verschiedenen projektspezifischen Zielstellungen SDL-Beschreibungen in ausführbare Programme überführen. Die Kombination von SDL mit einer weiteren Spezifikationstechnik, ASN.1, spielt hier eine besondere Rolle. Durch die aktive Mitarbeit des Autors bei der SDL-Sprachstandardisierung werden in der Arbeit auch Vorschläge präsentiert, die über das Potential der vorhandenen Werkzeuge hinausgehen. Das schließt beispielsweise die Bewertung der neuen, in der Praxis noch nicht etablierten, SDL-Version aus dem Jahr 2000 mit ein. / SDL in the language version which was standardized in 1996 is the most-used language in the telecommunication domain for the specification of protocols today. An essential aspect of the language development since 1998 is the availability of a formal basis for semantic concepts. The algebraic technique ACT ONE is used for the data concept of the language. Although the requirement and the practical value of SDL is the execution a specification technique, this is impaired straight by the used data model. The problem is hidden by the supply of pre-defined data types. Because of the introduction of object oriented concepts in 1992 and because of the generally increasing importance of data for the protocol description the existing language problems are taking more and more attention. Individual solutions for the specification of data are the consequence with available SDL tools. In the presented document are pointed out the praxis motivated inadequacies as well as the formal discrepancy of the data concept. A general requirement catalogue and a methodology are designed for language modifications based on a systematic inspection of the SDL data concept. Furthermore important language modifications are introduced and evaluated with the focus to expression power and to execution. Instruments are provided thus, which are helpful to different SDL interest groups for the evaluation and for the application of SDL modifications. In the document presented data modifications are based on years of experience of the author in the implementation and application of tools that compile SDL specifications with different project-specific objectives into executable programs. The combination of SDL with a further specification technology, ASN.1, plays an important role here. Because of the active role of the author in the SDL standardization process also suggestions are presented going beyond the potential of the existing tools. That includes for example the evaluation of the new, in practice not yet established SDL version, published in 2000.
7

The possible roles of soybean ASN genes in seed protein contents.

January 2006 (has links)
Wan Tai Fung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 102-111). / Abstracts in English and Chinese. / Thesis committee --- p.i / Statement --- p.ii / Abstract --- p.iii / Chinese Abstract --- p.v / Acknowledgements --- p.vii / General Abbreviations --- p.ix / Abbreviations of Chemicals --- p.xi / Table of Contents --- p.xii / List of Figures --- p.xvi / List of Tables --- p.xvi / Chapter 1 --- Literature Review --- p.1 / Chapter 1.1 --- Soybeans --- p.1 / Chapter 1.1.1 --- Nutrient composition of soybean --- p.1 / Chapter 1.1.2 --- Nitrogen fixation and assimilation in soybean --- p.3 / Chapter 1.1.3 --- The role in nitrogen allocation and controlling the nitrogen sink-source relationship of asparagine --- p.3 / Chapter 1.1.4 --- Characterization of asparagine synthetase --- p.8 / Chapter 1.1.4.1 --- Biochemistry and molecular background of plant asparagine synthetase --- p.8 / Chapter 1.1.4.2 --- Asparagine synthetase in Arabadopsis thaliana --- p.9 / Chapter 1.1.4.3 --- "Asparagine synthesis in soybean, Glycine max" --- p.10 / Chapter 1.1.4.4 --- "Asparagine synthetase in rice, Oryza sativa" --- p.11 / Chapter 1.2 --- Seed protein quality and quantity improvement --- p.13 / Chapter 1.2.1 --- Nutrition composition of rice --- p.13 / Chapter 1.2.2 --- Molecular approaches for improving seed storage protein quality --- p.14 / Chapter 1.2.2.1 --- Protein sequence modification --- p.14 / Chapter 1.2.2.2 --- Synthetic genes --- p.16 / Chapter 1.2.2.3 --- Overexpression of homologous genes --- p.17 / Chapter 1.2.2.4 --- Transfer and expression of heterologous genes --- p.18 / Chapter 1.2.2.5 --- "Manipulation of pathway synthesizing essential amino acids, aspartate family amino acid" --- p.19 / Chapter 1.2.3 --- Research in improving rice seed protein quality and quantity --- p.22 / Chapter 1.3 --- Hypothesis and objective of this study --- p.23 / Chapter 2 --- Materials and Methods --- p.25 / Chapter 2.1 --- Materials --- p.25 / Chapter 2.1.1 --- Plant materials --- p.25 / Chapter 2.1.2 --- Bacterial strains and vectors --- p.26 / Chapter 2.1.3 --- Growth conditions for soybean --- p.26 / Chapter 2.1.4 --- Chemicals and reagents --- p.26 / Chapter 2.1.5 --- "Buffer, solution and gel" --- p.26 / Chapter 2.1.6 --- Commercial kits --- p.27 / Chapter 2.1.7 --- Equipments and facilities used --- p.27 / Chapter 2.1.8 --- Primers --- p.27 / Chapter 2.2 --- Methods --- p.28 / Chapter 2.2.1 --- Growth condition for plant materials --- p.28 / Chapter 2.2.1.1 --- General conditions for planting soybean --- p.28 / Chapter 2.2.1.2 --- Soybean seedlings for gene expression profile analysis --- p.28 / Chapter 2.2.1.3 --- Mature soybean for gene expression profile analysis --- p.29 / Chapter 2.2.1.4 --- Mature soybean for cloning of AS I and AS2 full length cDNA --- p.30 / Chapter 2.2.1.5 --- Mature soybean seed for amino acid profile analysis --- p.30 / Chapter 2.2.1.6 --- General conditions for planting transgenic rice in CUHK --- p.30 / Chapter 2.2.1.7 --- Transgenic rice seedling for PCR screening --- p.31 / Chapter 2.2.1.8 --- Transgenic rice for functional test and seed for biochemical analysis --- p.31 / Chapter 2.2.2 --- Molecular techniques --- p.32 / Chapter 2.2.2.1 --- Total RNA extraction --- p.32 / Chapter 2.2.2.2 --- Denaturing gel electrophoresis for RNA --- p.33 / Chapter 2.2.2.3 --- Northern blot analysis --- p.33 / Chapter 2.2.2.3.1 --- Chemiluminescent detection --- p.33 / Chapter 2.2.2.3.2 --- Film development --- p.34 / Chapter 2.2.2.4 --- Preparation of single-stranded DIG-labeled PCR probes --- p.34 / Chapter 2.2.2.4.1 --- Primer design for the PCR probes of --- p.34 / Chapter 2.2.2.4.2 --- Amplification of AS1 and AS2 internal PCR fragments --- p.34 / Chapter 2.2.2.4.3 --- Quantitation of purified AS1 and AS2 PCR fragments --- p.35 / Chapter 2.2.2.4.4 --- Biased PCR to make single-stranded DNA probes --- p.35 / Chapter 2.2.2.4.5 --- Probe quantitation --- p.36 / Chapter 2.2.2.5 --- Probe specificity test --- p.37 / Chapter 2.2.2.6 --- Cloning of full length cDNA --- p.37 / Chapter 2.2.2.6.1 --- First strand cDNA synthesis from RNA of high protein content soybean leaf --- p.37 / Chapter 2.2.2.6.2 --- PCR for amplification of AS1 and AS2 full length cDNA --- p.38 / Chapter 2.2.2.6.3 --- Preparation of pBluescript II KS(+) T-vector for cloning --- p.38 / Chapter 2.2.2.6.4 --- Ligation of DNA inserts into pBluescript II KS(+) T-vector --- p.39 / Chapter 2.2.2.6.5 --- Preparation of E. coli DH5α CaCl2-mediaed competent cells --- p.39 / Chapter 2.2.2.6.6 --- Transformation of E. coli DH5α competent cell --- p.40 / Chapter 2.2.2.7 --- Screening of recombinant plasmids --- p.40 / Chapter 2.2.2.7.1 --- Isolation of recombinant plasimid DNA from bacterial cells --- p.41 / Chapter 2.2.2.7.2 --- PCR screening on recombinant plasmids --- p.41 / Chapter 2.2.2.7.3 --- DNA gel electrophoresis --- p.41 / Chapter 2.2.2.8 --- Sequencing and homology search --- p.42 / Chapter 2.2.2.9 --- Functional test using transgenic plant --- p.43 / Chapter 2.2.2.9.1 --- Preparation of chimeric gene constructs and recombinant plasmids --- p.43 / Chapter 2.2.2.9.2 --- Agrobacterium mediated transformation into rice calli to regenerate transgenic AS1/ AS2 rice --- p.44 / Chapter 2.2.2.10 --- PCR Screenig of homozygous and heterozygous transgenic plants --- p.44 / Chapter 2.2.2.10.1 --- Isolation of genomic DNA from transgenic plants --- p.45 / Chapter 2.2.2.10.2 --- PCR screening using genomic DNA --- p.46 / Chapter 2.2.2.11 --- Quantitative PCR analysis on transgenic plants --- p.48 / Chapter 2.2.3 --- Biochemical Analysis --- p.49 / Chapter 2.2.3.1 --- Quantitative amino acid analysis in mature soybean seeds --- p.49 / Chapter 2.2.3.2 --- Quantitative amino acid analysis in mature transgenic rice grain --- p.49 / Chapter 3 --- Results --- p.50 / Chapter 3.1 --- Amino acid analysis on mature soybean seeds --- p.50 / Chapter 3.2 --- Expression pattern analysis of AS genes by Northern Blot analysis --- p.54 / Chapter 3.2.1 --- Making of single strand digoxigenin (DIG)-labeled probe --- p.54 / Chapter 3.2.2 --- Probe specificity --- p.57 / Chapter 3.2.3 --- AS expression level under light/dark treatments by Northern Blot analysis --- p.58 / Chapter 3.2.4 --- AS expression level in young seedlings by Northern Blot analysis --- p.62 / Chapter 3.2.5 --- AS expression level in podding soybean by Northern Blot analysis --- p.64 / Chapter 3.3 --- Cloning of AS genes from high protein content soybeans --- p.66 / Chapter 3.3.1 --- "PCR amplification of AS1 and AS2 full length cDNA from the first-strand cDNA of high portein content cultivar soybean, YuDoul2" --- p.66 / Chapter 3.3.2 --- Nucleotide sequences analysis of AS1 and AS2 full-length cDNA clones --- p.68 / Chapter 3.4 --- Construction of AS1 and AS2 transgenic rice --- p.75 / Chapter 3.4.1 --- Construction of AS1 and AS2 constructs --- p.75 / Chapter 3.4.2 --- Transformation of chimeric gene constructs into Agrobacterium tumefaciens --- p.75 / Chapter 3.4.3 --- Agrobacterium mediated transformation into Oryza sativa calli to regenerate transgenic rice --- p.76 / Chapter 3.4.4 --- PCR screening of transgene from transgenic AS1 and AS2 rice --- p.76 / Chapter 3.4.5 --- Quantitative PCR analysis of the transgene expression --- p.81 / Chapter 3.4.6 --- Quantitative amino acid analysis in mature transgenic rice grain --- p.83 / Chapter 4 --- Discussion --- p.89 / Chapter 4.1 --- The role of asparagine and asparagine synthetase in nitrogen assimilation and sink-source relationship in soybean --- p.89 / Chapter 4.2 --- Comparative study of AS between different high seed protein content crops --- p.92 / Chapter 4.3 --- The attempt to find out the reason for the strong AS1 expression detected in high protein soybean cultivars --- p.92 / Chapter 4.4 --- Other factors affecting seed protein contents --- p.93 / Chapter 4.5 --- Rice seed quality improvement by nitrogen assimilation enhancement --- p.94 / Chapter 4.6 --- Comparative study of amino acid profile and seed total protein in other transgenic rice --- p.95 / Chapter 4.7 --- Possible reason of higher seed protein content in AS2 transgenic rice --- p.96 / Chapter 4.8 --- Selectable marker --- p.97 / Chapter 5 --- Conclusion and Prespectives --- p.99 / Chapter 6 --- References --- p.102 / Chapter 7 --- Appendix --- p.112 / Appendix I: Major chemicals and reagents used in this research --- p.112 / "Appendix II: Major buffer, solution and gel used in this research" --- p.114 / Appendix III: Commercial kits used in this research --- p.117 / Appendix IV: Major equipments and facilities used in this research --- p.118 / Appendix V: Primer list --- p.119
8

Fuzzing Radio Resource Control messages in 5G and LTE systems : To test telecommunication systems with ASN.1 grammar rules based adaptive fuzzer / Fuzzing Radio Resource Control-meddelanden i 5Goch LTE-system

Potnuru, Srinath January 2021 (has links)
5G telecommunication systems must be ultra-reliable to meet the needs of the next evolution in communication. The systems deployed must be thoroughly tested and must conform to their standards. Software and network protocols are commonly tested with techniques like fuzzing, penetration testing, code review, conformance testing. With fuzzing, testers can send crafted inputs to monitor the System Under Test (SUT) for a response. 3GPP, the standardization body for the telecom system, produces new versions of specifications as part of continuously evolving features and enhancements. This leads to many versions of specifications for a network protocol like Radio Resource Control (RRC), and testers need to constantly update the testing tools and the testing environment. In this work, it is shown that by using the generic nature of RRC specifications, which are given in Abstract Syntax Notation One (ASN.1) description language, one can design a testing tool to adapt to all versions of 3GPP specifications. This thesis work introduces an ASN.1 based adaptive fuzzer that can be used for testing RRC and other network protocols based on ASN.1 description language. The fuzzer extracts knowledge about ongoing RRC messages using protocol description files of RRC, i.e., RRC ASN.1 schema from 3GPP, and uses the knowledge to fuzz RRC messages. The adaptive fuzzer identifies individual fields, sub-messages, and custom data types according to specifications when mutating the content of existing messages. Furthermore, the adaptive fuzzer has identified a previously unidentified vulnerability in Evolved Packet Core (EPC) of srsLTE and openLTE, two open-source LTE implementations, confirming the applicability to robustness testing of RRC and other network protocols. / 5G-telekommunikationssystem måste vara extremt tillförlitliga för att möta behoven för den kommande utvecklingen inom kommunikation. Systemen som används måste testas noggrant och måste överensstämma med deras standarder. Programvara och nätverksprotokoll testas ofta med tekniker som fuzzing, penetrationstest, kodgranskning, testning av överensstämmelse. Med fuzzing kan testare skicka utformade input för att övervaka System Under Test (SUT) för ett svar. 3GPP, standardiseringsorganet för telekomsystemet, producerar ofta nya versioner av specifikationer för att möta kraven och bristerna från tidigare utgåvor. Detta leder till många versioner av specifikationer för ett nätverksprotokoll som Radio Resource Control (RRC) och testare behöver ständigt uppdatera testverktygen och testmiljön. I detta arbete visar vi att genom att använda den generiska karaktären av RRC-specifikationer, som ges i beskrivningsspråket Abstract Syntax Notation One (ASN.1), kan man designa ett testverktyg för att anpassa sig till alla versioner av 3GPP-specifikationer. Detta uppsatsarbete introducerar en ASN.1-baserad adaptiv fuzzer som kan användas för att testa RRC och andra nätverksprotokoll baserat på ASN.1- beskrivningsspråk. Fuzzer extraherar kunskap om pågående RRC meddelanden med användning av protokollbeskrivningsfiler för RRC, dvs RRC ASN.1 schema från 3GPP, och använder kunskapen för att fuzz RRC meddelanden. Den adaptiva fuzzer identifierar enskilda fält, delmeddelanden och anpassade datatyper enligt specifikationer när innehållet i befintliga meddelanden muteras. Dessutom har den adaptiva fuzzer identifierat en tidigare oidentifierad sårbarhet i Evolved Packet Core (EPC) för srsLTE och openLTE, två opensource LTE-implementeringar, vilket bekräftar tillämpligheten för robusthetsprovning av RRC och andra nätverksprotokoll.
9

Utveckling av ett öppet Home Automation-protokoll för användning över IP-nätverk / Development of an open Home Automation protocol for use over IP networks

Johnsson, Kim, Turfors, Christoffer, Ericson, Eric January 2010 (has links)
<p>Detta arbete tar upp utvecklingen av ett nytt protokoll för användning inom Home Automation över IP-nätverk, med stor vikt på flexibilitet och enkelhet. Vi valde att utveckla ett nytt protokoll för Home Automation då en granskning av dagens protokoll visar att dessa inte är tillräckligt öppna eller flexibla för att passa alla enheter som används eller alla scenarion som kan uppstå.</p><p>I våra litteraturstudier samlades information in som skapade grunderna för vårt protokoll och gav oss en större inblick i teknikerna bakom dagens tekniker inom home automation. Detta gav oss även möjlighet att senare jämföra vårt färdiga protokoll med redan existerande protokoll för att se om vi lyckats skapa något som kan användas. Metoden vi valde för att utveckla protokollet är en generell designmetod där vi efter granskningen av tidigare protokoll tar fram ett antal punkter som det nya protokollet skall uppnå. Det visade sig dock vara problematiskt att få fram svar om vissa protokoll så vi frångick metoden genom att istället utveckla protokollet utefter ett antal olika scenarion som det bör kunna hantera.</p><p>Resultatet av arbetet är ett protokoll som uppfyllde nästan alla mål vi satt upp för det. I de fall vi inte lyckades med att uppfylla målen har vi möjliggjort för framtida expanderingar.</p> / <p>This report covers the development of a new protocol for use in Home Automation over IP networks, with focus on flexibility and simplicity. We chose to develop a new protocol for Home Automation because a review of current protocols suggests that these aren't open or flexible enough to suit every device in use or every scenario that might be applicable.</p><p>In our literature studies we gathered information for use as the basis of our protocol and give us more insight into the technologies behind current home automation protocols. This also gave us the opportunity to compare our finished protocol with existing protocols. The method we chose for developing the protocol is a generic design method where after reviewing existing protocols, we establish a number of goals for the new protocol. It did however turn out to be difficult to acquire relevant information about some of the protocols. Because of this we used a slightly different approach, basing the new protocol on a number of scenarios we want it to be able to handle.</p><p>The result is a protocol which satisfied almost every goal we established. For the few it didn't, we made it possible to satisfy them with future expansions.</p>
10

Analysis of Communication Architecture of GCDC 2011 / Analysis of Communication Architecture of GCDC 2011

Khaksari, Mohammadreza January 2011 (has links)
This thesis report presents a method to analyze the communication architecture for the Intelligent Transportation Systems (ITS). The report also includes a case study on ASN.1 notation and analysis of its encoding rules. Included in the report is also: (i) accompanying instruction on how to use ASN.1 compilers to produce the C/C++ message encoder/decoder, and (ii) analysis of Non-IP communications of Communication Access for Land Mobiles (CALM-FAST) protocol stack in ITS. The thesis is a part of the research project entitled “SCOOP”, a joint project between SCANIA CV AB and KTH. The purpose of this thesis is to contribute to the ultimate goal, which is to equip a vehicle with necessary hardware and software technology to provide a platooning behavior in the GCDC 2011 competition. This goal is achieved by the means of wireless communication system for both vehicle to vehicle and vehicle to road side units communications in the platoon. Overall, this thesis introduces the important usage of ASN.1 in implementation of cut-edge telecommunication systems especially in V2V and V2I communication; and clarifies the CALM-FAST protocol stack in mobile nodes. / Kartlägga CALM-FAST protokollet och hur det användes tillsammans med den i tävlingen GCDC 2011 fastslanga kommunikationsprotokollet. GCDC var ett tävling i kooperativ körning arrangerad och initierad av Hollänska TNO och gick ut på att få fordon att agera tillsammans beserat på information sänt via WLAN 802.11p. ASN.1 användes och ingick i analysen.

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