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Rose, Daniel [Verfasser]. "An elastic primal active-set method for structured QPs / Daniel Rose". Hannover : Technische Informationsbibliothek (TIB), 2018. http://d-nb.info/1169697267/34.
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Ahlenius, Linda. "Yrkesstolthetens komponenter hos anställda på Försäkringskassan Dalarna". Thesis, Högskolan Dalarna, Psykologi, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:du-2765.
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Syftet med föreliggande undersökning var att identifiera faktorer som bidrog till känslan av "yrkesstolthet" hos anställda vid Försäkringskassan Dalarna inkluderande personalens tillfredsställelse med yrkesrollen. Sammanlagt 163 personer, 123 kvinnor och 40 män, från 25 till 66 år (X= 49,8 år) deltog i undersökningen. Denna genomfördes med hjälp av General Nordic Questionnaire for Psychological and Social Factors at Work (QPS Nordic) inkluderande 123 frågor samt 9 frågor gällande yrkesrollen. Frågorna besvarades väsentligen med hjälp av en 5-gradig skala av Likert-typ. Huvudresultatet uträknades med hjälp av Cronbachs Alpha, Principal Component Analysis och multipel regressionsanalys. Det konstaterades att beroendevariabeln "yrkesstolthets" variation förklarades till 62,7% av oberoende-variablerna "interaktionsintelligens" "yrkesrealism", "arbetstillfredsställelse" och "arbetsengagemang". Även kön, ålder, utbildning och yrkeserfarenhet hade betydelse.
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Karlsten, Veronika. "Yrkesrelaterad livskvalitet - upplevd påverkan av att hjälpa". Thesis, Umeå universitet, Institutionen för psykologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-104530.
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Posttraumatiskt Stressyndrom (PTSD) är en erkänd diagnos som listades i DSM-III år 1980. Något som inte har uppmärksammats på samma sätt är de symptom som upplevs av individer som i andra hand exponeras för trauma. Exempelvis de som tar emot en primärdrabbads berättelse. För att beskriva påverkan av att ta emot en primärdrabbads berättelse har termen yrkesrelaterad livskvalitet (Professional quality of life) använts. Forskning med fokus på yrkesrelaterad livskvalitet har bedrivits inom många olika yrken. En grupp som berörts är personal som engagerar sig i våld i nära relationer men litteraturen är begränsad. I förevarande studie användes ProQOL (som består av medkänsletillfredsställelse, utbrändhetsupplevelse och sekundär traumatisering) och QPS Nordic för att undersöka den yrkesrelaterade livskvaliteten hos dem som engagerar sig som hjälpare i kvinnojourer. I studien deltog 55 kvinnor som är anställda eller frivillig/volontärarbetare på kvinnojour. Studien utreder även om tillgång till handledning, upplevt socialt stöd, antal timmar i kontakt med hjälpsökande per vecka och anställningsform påverkar den yrkesrelaterade livskvaliteten. Resultaten tyder på att det finns både negativ och positiv påverkan av ett engagemang som hjälpare. Utbrändhetsupplevelse har stark korrelation med antal timmar i kontakt med hjälpsökande samt en moderat korrelation med socialt stöd. Sekundär traumatisering har stark korrelation med antal timmar i kontakt med hjälpsökande. Resultaten visar även att socialt stöd, antal timmar i kontakt med hjälpsökande och tillgång till handledning förklarar en hög andel av variansen för sekundär traumatisering och utbrändhetsupplevelse samt att anställningsform inte tycks ha betydelse för den yrkesrelaterade livskvaliteten.
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Edin, Marina, i Kristina Vallner. "Psykosocial arbetsmiljö och förutsättningar att bedriva systematiskt arbetsmiljöarbete för första linjens chefer i primärvården". Thesis, Umeå universitet, Institutionen för omvårdnad, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-125413.
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Cheferna inom vård och omsorg i offentliga organisationer har hög arbetsbelastning och ett komplext uppdrag. Ofta finns rutiner för det systematiska arbetsmiljöarbetet, men de är bristfälliga och används inte. Syftet var att undersöka hur första linjens chefer i primärvården upplevde sin psykosociala arbetsmiljö samt deras förutsättningar att bedriva systematiskt arbetsmiljöarbete. En tvärsnittsstudie där samtliga 126 första linjens chefer från fyra landsting i primärvården deltagit, med svarsfrekvens 51%. I studien har enkät QPS Nordic 34+ använts samt 10 kompletterande frågor om systematiskt arbetsmiljöarbete. Analys delvis med referensdata och Pearsons korrelation. Cheferna hade en hög arbetsbelastning och arbetet tenderade att hopa sig. I jämförelse med referensdata 3,2 var chefernas medelvärde 4,02. De upplevde gott stöd, bra klimat och hade goda kunskaper för arbetsuppgifterna, men 32,8% av cheferna ansåg att de inte alls eller bara lite var insatt i AFS 2015:4. Avseende om arbetsbelastningen gav utrymme för att bedriva systematiskt arbetsmiljöarbete svarade fyra femtedelar av alla chefer inte alls eller i viss mån. Trots det goda stöd som cheferna upplevde är det viktigt att förebygga hög arbetsbelastning, då varaktig stress kan leda till ohälsa. Förutsättningar att bedriva systematiskt arbetsmiljöarbete begränsas också av deras arbetsbelastning och kan innebära negativa konsekvenser för medarbetarna.
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van, Haandel Andre. "Irradiation as an alternative phytosanitary treatment for Arhopalus ferus and Hylurgus ligniperda". Thesis, University of Canterbury. School of Forestry, 2014. http://hdl.handle.net/10092/10506.
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Wood products all require treatment to mitigate phytosanitary risk prior to exportation. The most common phytosanitary treatment applied to Pinus radiata logs is Methyl Bromide (MeBr). The Environmental Protection Agency (EPA) in 2010 stated that MeBr must not be release into the atmosphere past 2020. This poses a problem for New Zealand log exports. Radiation has been identified as a possible alternative phytosanitary treatment for export wood products.
This study aimed to quantify the effective dose of radiation necessary to sterilise two forest pest species; Arhopalus ferus and Hylurgus ligniperda. These species are representative of two different types of forestry pests; bark beetles (H. ligniperda) and wood borers (A. ferus). All applicable life stages for both species were tested.
Arhopalus ferus adults were the most susceptible life stage identified with an LD99 of 30.2Gy ± 13.5 Gy (95% confidence interval). Arhopalus ferus eggs were less susceptible with a LD99 of 750Gy ± 776Gy observed; however there is low confidence in this result due to a methodological issue in one treatment replicate. Hylurgus ligniperda eggs were observed to be less susceptible than A. ferus eggs with a LD99 of 289Gy ± 92Gy. Results for the other life stages were inconclusive due to poor control survival, however the information gained was used to develop improved methods for further experimentation, which is on-going and showing positive results so far.
The results of this experiment have indicated that radiation can be an effective method of sterilising forestry pests. To date radiation has not been used as phytosanitary risk mitigation for wood exports; however it is widely used for risk mitigation in agricultural products. Currently there remains a large amount of unknown information regarding, the effectiveness for irradiation of logs, the effective dose require for sterilisation of the most tolerant forestry pest and public acceptability of irradiation as a phytosanitary treatment. These knowledge gaps and an economic assessment must be completed before irradiation can be used as a phytosanitary risk mitigation technique for forestry products.
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Ede, Andrew, i andrew ede@premiers qld gov au. "The Prevention of Police Corruption and Misconduct: A Criminological Analysis of Complaints Against Police". Griffith University. School of Criminology and Criminal Justice, 2000. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20030102.114721.
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The reform measures recommended by the Commission of Inquiry into Possible Illegal Activities and Associated Police Misconduct (referred to as the "Fitzgerald Inquiry") radically transformed the face of policing in Queensland. The most significant of these recommendations was the establishment of an external oversight body, the Criminal Justice Commission (CJC), which has independence from executive government and holds the power to investigate not only police but any public servant or politician. Other recommendations included "Whistleblower" legislation, increasing sanctions for serious misconduct, lateral recruitment and promotion by merit rather than seniority. The first main research question tested in this thesis is whether these reform measures have produced improvements in the following areas: the efficiency and effectiveness of the processes for dealing with complaints against police; public confidence in those processes and the public standing of the Queensland Police Service (QPS) generally; standards of police behaviour; the incidence of corrupt conduct; and police attitudes towards reporting misconduct by their fellow officers. These Fitzgerald Inquiry reforms were strategies primarily derived from two schools of thought describing the nature and cause of police corruption: deterrence based theory (including "individual" or "rotten apple" theory) and cultural (also labeled "cultural" or "socialisation") based theory. To date most strategies used to combat police corruption have been underpinned by these theories. A third theory - situational based theory (sometimes titled "environmental" or "opportunity" theory) - which has had success in crime prevention, has been scarcely used in the area of police corruption. However, an extensive body of research has affirmed the effects of situational factors on police behaviour, suggesting the potential for the application of situational crime prevention initiatives in combatting police corruption. The second research question proposed in this thesis is whether situational based theory could also be beneficial in the prevention of police corruption. Data drawn upon to test the first research question were interviews and surveys with police officers, public attitude surveys and statistics from the processing of complaints against police. Although each source has limitations, collectively the data are sufficiently comprehensive - and robust - to defend conclusions about the general direction of the changes which have occurred. These data indicate that the Fitzgerald Inquiry reforms have, at least to some degree, had their intended impact on the QPS. These reforms have contributed to an apparent improvement in public confidence in the complaints system and the QPS generally. Moreover, the available evidence suggests that the Fitzgerald Inquiry reforms have resulted in a weakening of the police code of silence. As far as the specific issue of corruption in the QPS is concerned, it is difficult to draw firm conclusions from existing data sources. However, the weight of the available evidence is that such conduct is less pervasive and occurs at lower levels than was the case in the pre-Fitzgerald Inquiry QPS. It is very difficult to ascertain which reform components were the most effective and which were not helpful at all, as these reform measures were initiated simultaneously. For example, the negative elements of the police culture may have been eliminated or reduced but whether it was the cultural strategies or one of the deterrence based strategies influencing officer behaviour remains unknown. The second main research question the thesis poses is that the use of situational crime prevention techniques has potential for contributing to the prevention of police corruption. A situational analysis of complaints against police data, including the development of a typology for classifying types of police corruption and misconduct, was used as an example of how this may be accomplished in Queensland. The study provides some, albeit limited, support for the hypothesis that situational crime prevention methods are applicable to police corruption. Based upon three years of complaints data, enough homogenous cases were gathered to enable the analysis of four categories of police corruption - Opportunistic Thefts, Driving under the Influence, Assault (while off-duty), and Theft from Employer. Given that this study only used three years of complaints data held by the CJC and more than nine years of data exist, productive situational analyses of many other categories of corruption is probable. This study also illustrated that complaints against police data are being under utilised by the QPS and the CJC. For future research in the situational analysis of complaints data, I recommend improving the gathering of data from complaints files for storage in electronic form to enable situational prevention analysis to be conducted more readily. A geographical example was used to illustrate further how complaints against police data could be more extensively utilised as a prevention tool. This analysis was conducted at an organisation unit level determined primarily by geographical factors. The complaint patterns of units of similar "task environments", as measured by unit size and type of duties performed, were compared in an attempt to identify those units experiencing the presence or absence of "bad apples" or a "negative culture". This study led to the conclusion that a divisional analysis of complaints data can provide information valuable in combatting police corruption. When task environment was held constant, it was possible to identify units experiencing the effects of possible "bad apples" and/or "negative cultures". Once these particular units were identified, intervention strategies to address the units' particular problem could be constructed. Future research in this area would involve ongoing divisional data analysis followed-up by individual assessment of officers identified as "bad apples", or a "compare-and-contrast" procedure to distinguish features requiring correction in units identified as having a "negative culture". The research findings presented in this thesis are that progress has occurred in a number of areas in addressing the problems identified by the Fitzgerald Inquiry, but that there is undoubtedly scope for more to be achieved. Despite the very significant increase in the resources and powers available to investigators post-Fitzgerald, it is still difficult to prove that a police officer engaged in misconduct, or that other officers were aware of this fact and had failed to take action, because of the constraints imposed by evidentiary and legal requirements. Thus, while it is vital to maintain an effective and credible independent complaints investigation system and ensure that there is a proper internal discipline process in place, the scope for increasing the "deterrent power" of the present system is limited. Putting more resources into complaints investigations might make a difference at the margins, but is unlikely to lead to a significant increase in the probability of a complaint being substantiated and a sanction imposed. Investing more resources in investigations has an additional cost in that such resources are then lost to other efforts to combat corruption that may provide more fruitful results in the long term. The value of an occasional substantiation is placed above the ability to engage in a large amount of prevention work. Inevitably then, three clear messages are apparent. First, continued effort must be made to modify the organisational climate of the QPS in terms of commitment to integrity. Recommended strategies to accomplish this end are to continue the recruitment of more educated, female and older officers to reduce police-citizen conflict and the negative elements of the police culture, and also to develop a comprehensive, integrated approach to ethics education for QPS officers at all ranks and positions. Second, other forms of deterrence against misconduct are needed such as the use of covert strategies like integrity testing which could be conducted in conjunction with the CJC. Third, a greater emphasis needs to be placed on developing and implementing preventive strategies. This thesis has shown that valuable prevention strategies can be gained from situational and divisional analysis of complaints data, and a range of proactive management options based upon situational crime prevention theory are recommended. These strategies have application in any police service.
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Legorgeu, Carole. "Amélioration des estimations quantitatives des précipitations à hautes résolutions : comparaison de deux techniques combinant les observations et application à la vérification spatiale des modèles météorologiques". Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2013. http://tel.archives-ouvertes.fr/tel-00872131.
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Ces dernières années, de nombreux efforts ont été entrepris pour mieux comprendre les phénomènes précipitants parfois à l'origine de crues de cours d'eau et d'inondations ravageuses. Courant 2009, un consortium auvergnat a été mis en place pour notamment surveiller et prévoir ces événements. Les travaux menés dans cette thèse visent d'une part à améliorer les estimations quantitatives des précipitations (QPE) et d'autre part à vérifier les prévisions issues de modèles numériques sur de petites zones d'étude telles qu'une agglomération. L'observation des précipitations peut être réalisée à l'aide soit d'un pluviomètre qui fournit une mesure directe et précise de la quantité de pluie tombée au sol mais ne renseigne pas sur la variabilité spatiale des pluies soit d'un RADAR météorologique qui donne une représentation détaillée de la structure spatiale des précipitations mais dont les estimations sont sujettes à diverses erreurs d'autant plus prononcées en régions montagneuses. Le premier défit de cette thèse a été de trouver la meilleure façon de combiner ces deux informations complémentaires. Deux techniques géostatistiques ont été sélectionnées pour obtenir la meilleur QPE : le krigeage avec dérive externe (KED) et la fusion conditionnée (MERG). Les performances de ces deux méthodes ont été comparées au travers de deux domaines d'étude qui présentent des résolutions spatio-temporelles différentes. La seconde partie de cette thèse est consacrée à la mise en place d'une méthodologie fiable permettant de comparer spatialement les champs de QPE alors reconstruits et les prévisions quantitatives des précipitations (QPF). L'effort fut porté sur le modèle " Weather Research et Forcasting " (WRF). Une étude préliminaire a été réalisée pour tester les capacités du modèle et plus particulièrement des schémas de microphysique à reproduire la pluie. Cette étude assure ainsi l'obtention de prévisions réalistes pour une application sur des cas réels. L'appréciation de la qualité des QPF s'est focalisée sur la quantification spatiale des erreurs de prévision en termes de structure, d'intensité et de localisation des systèmes précipitants (SAL : Wernli et al. 2008, 2009).
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Islam, Mohammad Shahidul, i Syed Nasir Mehdi. "How Different QoS Mechanisms Affect VoIP QoS Metrics". Thesis, Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-15337.
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Voice over Internet Protocol (VoIP) has become a key technology of communication. Our work has been a practical implemenation of different scenarios to show that VoIP voice quality can be improved by adopting certain Quality of Service(QoS) measures such as classification, marking or queuing. It has been discussed that different QoS metrics like delay, packet loss and jitter could affect the voice quality of VoIP. To reduce the negative affects, one option is to implement certain QoS mechanisms with some set of configurations. For this purpose, Cisco IP phones have been configured in our topology with routers, switches, traffic generators, end stations and VoIP quality monitoring software called VQmanager. Tests have been divided into two sets. In one test a fixed bandwidth of 70 kbps is set while in the other test a random bandwidth is set with trafic generators unleashing packets of traffic. In both these tests further scenarios with configurations are worked out. They include no QoS, Auto Qos and Customized Qos mechanisms. Results have been indicative of top performance by the Customized QoS mechanism, in both sets of tests, followed by Auto QoS and no QoS mechanisms. It has been observed that a customized scenario could be a particular configuration to any organization’s needs and that will have the lowest delay, jitter and packet loss which are the main QoS metrics that impact the voice quality of VoIP. It can be fundamentally composed of classification of voice, data or web-traffic, marking and queuing depending upon the need of the organization. It is finally suggested to carry more tests in companies to get more data for analysis
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Bchini, Tarek. "Gestion de la Mobilité, de la Qualité de Service et Interconnexion de Réseaux Mobiles de Nouvelle Génération". Thesis, Toulouse, INPT, 2010. http://www.theses.fr/2010INPT0016/document.
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Avec l’évolution rapide des technologies réseaux et télécoms radios mobiles, les chercheurs sont actuellement en train de préparer l’arrivée d’une nouvelle génération baptisée 4G. Le réseau de 4ème génération qui est encore l’objet de travaux de recherche vise à améliorer l’efficacité spectrale et à augmenter la capacité de gestion du nombre des mobiles dans une même cellule. Il tend à offrir des débits élevés en situation de mobilité à grande ou faible vitesse. Il vise aussi à permettre et à faciliter l’interconnexion et l’interopérabilité entre différentes technologies existantes en rendant transparent à l’utilisateur le passage entre les réseaux. Enfin, il vise à éviter l’interruption des services durant le transfert intercellulaire, et à basculer l’utilisation vers le tout IP. Dans ce contexte, nous nous sommes intéressés en premier lieu aux problématiques de la QoS en situation de mobilité au sein d’une technologie candidate à la 4G (WiMAX mobile) pour du trafic temps-réel. Pour cela, nous avons comparé la performance de plusieurs protocoles de mobilité dans le contexte du Handover de niveau 2 et de niveau 3 et plus. Nous avons pour cela fait varier les modèles de mobilité, les configurations et les scénarios. Enfin, nous avons modélisé un algorithme décisionnel qui gère le Handover dans le WiMAX mobile en fonction de plusieurs paramètres d’entrées. Au travers de ces études, nous avons dégagé des protocoles de mobilité qui offrent un niveau de QoS acceptable pour un trafic temps-réel dans le cadre des scénarios envisagés. En deuxième lieu, nous nous sommes concentrés sur les problèmes d’interconnexion et d’interopérabilité entre les réseaux en tenant compte de la mobilité et du Handover vertical entre deux technologies. Pour cela, nous avons proposé de comparer des protocoles de mobilité puis de les combiner afin de diminuer les délais des trafics temps-réel au cours du Handover. Au niveau de l’interconnexion, nous avons proposé des modèles entre WiMAX mobile et de nombreux autres standards (802.11e, UMTS, DVB-S/RCS, LTE). Outre les solutions d’interconnexion, nous avons également mis en évidence la ou les combinaisons de protocoles de gestion de la mobilité qui permettent de garantir de la QoSWith the rapid evolution of mobile radio telecommunications and networks technologies, researchers are currently preparing the arrival of a new generation called 4G. The 4th generation network aims to improve spectral efficiency and increase capacity to manage a large number of mobiles in a cell. It tries to provide high flow rates under high or low mobility. It also aims to enable and facilitate the interconnection and the interoperability between different technologies allowing transparent transition between networks. Finally, it aims to avoid interruption of services during the handover, and to switch an all-IP system. In this context, we are concerned first with QoS and mobility issues in Mobile WiMAX for the real-time traffic. We compared the performance of several mobility protocols in the context of the level 2 and level 3+ handovers. Several mobility models, configurations and scenarios were considered. Finally, we modeled a decision algorithm that manages the handover in mobile WiMAX based on several input parameters.Through these studies, we have identified mobility protocols that provide an acceptable QoS level for real-time traffic under the proposed scenarios. Secondly, we focused on the problems of interconnection and interoperability between networks, taking into account the mobility and vertical handovers between two technologies. For this, we proposed to compare mobility protocols or combine them to reduce delays for real-time traffic during the handover. We also proposed interconnection models between mobile WiMAX and many other standards (802.11e, UMTS, DVB-S/RCS, LTE). Besides interconnection solutions, we also highlighted the combination or combinations of management mobility protocols that can guarantee QoS
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Cushnie, John. "QoS charging for Internet access networks : the wireless QoS gateway". Thesis, Lancaster University, 2003. http://eprints.lancs.ac.uk/12300/.
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WANG, XIAODONG. "QoS ISSUES AND QoS CONSTRAINED DESIGN OF WIRELESS SENSOR NETWORKS". University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1144634884.
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Jonsson, Björn. "Bluetooth QoS Scheduler". Thesis, KTH, Mikroelektronik och Informationsteknik, IMIT, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-93114.
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Bluetooth is a low cost, short-range radio technology that enables electronic devices to communicate wirelessly via ad-hoc networks. Different kinds of applications may run over these networks, some of these applications with particular Quality of Service (QoS) requirements. One such application could for instance be an Audio application which need data frames to be delivered at regular interval to work properly. The communication over Bluetooth links is totally controlled by one of the participating nodes. Since this node controls the traffic and thereby controls the QoS within the network its communicating behaviour is of great importance for maintaining QoS reservations. A central part in maintaining QoS reservations is the scheduler, which prioritises between different tasks to be done such as which device that is allowed to transmit next. There is no standardised way to implement the Bluetooth scheduler. However, a Bluetooth scheduler should be able to handle QoS reservations, maintain fairness among the participating nodes, and utilise the available bandwidth efficiently. Furthermore a key requirement in Bluetooth is simplicity, therefore a Bluetooth scheduling algorithm should be of low complexity. This master thesis presents a new patented solution for an intra-piconet scheduling algorithm that is capable of maintaining QoS reservation, while being fair and also meet the low complexity requirement. This algorithm is presented in detail in the thesis and has been implemented in an ns2- based Bluetooth simulator. Simulations in this simulator are presented that verifies the scheduling algorithms functionality.Bluetooth är en standard för trådlös ad-hoc kommunikation. Denna standard definierar i antalet noder begränsade nätverk (piconet) som kan kopplas samman till större nätverk (scatternet). Många olika typer av applikationer kan tänkas använda dessa nätverk, vissa av dessa med speciella krav på Quality of Service (QoS). Ett exempel så en dylik applikation är ljudöverföringar som kräver att data överförs med jämna mellanrum för att kunna fungera tillfredställande. Kommunikationen över ett Bluetooth-piconet kontrolleras helt av en av de deltagande enheterna. Eftersom denna enhet kontrollerar trafiken kontrollerar den också upprätthållandet av QoS reservationerna. En central del i detta upprätthållande är schemaläggaren, som är den del i en Bluetoothenhet som prioriterar mellan olika saker som ska utföras. Ett exempel på en sådan prioritering kan vara vilken enhet i nätverket som ska få kommunicera härnäst. Bluetooth standarden beskriver inte hur denna schemaläggare ska implementeras. Grundläggande krav på en Bluetooth schemaläggare är att den ska kunna hantera och upprätthålla QoS reservationer samtidigt som den delar den befintliga kapaciteten på ett rättvist och effektivt sätt mellan de deltagande enheterna. Vidare bör den ha en låg komplexitet eftersom enkelhet är ett krav på alla delar i ett Bluetoothsystem. Detta examensarbete presenterar en ny patenterad algoritm för schemaläggning i begränsade Bluetoothnät som är kapabel att upprätthålla QoS-reservationer, samtidigt som den distribuerar den tillgängliga kapaciteten på ett rättvist sätt. Algoritmen möter också upp till kravet på låg komplexitet. Rapporten innehåller vidare simuleringar av algoritmens funktion, dessa har utförts i en ns2-baserad Bluetooth miljö och verifierar algoritmens funktionalitet.
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Lahdenperä, J. (Juho). "QoS 4G-verkoissa". Bachelor's thesis, University of Oulu, 2017. http://urn.fi/URN:NBN:fi:oulu-201711153110.
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Tutkielma on kirjallisuuskatsaus, jossa perehdytään nykyään käytettäviin Quality of Service (QoS) ratkaisuihin 4G-verkoissa. QoS on tärkeä niin käyttäjän, kuin palvelun tarjoajan näkökulmasta. QoS:n avulla varmistetaan kullekin verkon käyttäjälle riittävä palvelun taso. QoS:n tarkastelua tarvitaan myös erilaisten järjestelmien suunnittelussa, että ymmärretään mitä järjestelmältä vaaditaan. 4G-verkon QoS parametrit on standardisoitu ja laitteiden QoS-mekanismit ovat globaaleilla televiestintämarkkinoilla tärkeä kilpailutekijäThis thesis is a literature review, that orients to the concept of modern day Quality of Service solutions in 4G-networks. QoS is important from the users’ as well as the service provider’s point of view. QoS provides a level of service for each network user and it is also required in system design to know what is required from the system. QoS parameters of 4G network are standardized and the QoS mechanisms are an important competitive factor in the global telecommunications market
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Kopecký, Lukáš. "QMS průmyslového podniku". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-254327.
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The subject of this master´s thesis is the improvement of a quality management system in selected industrial company using the DMAIC methodology. For this purpose, current status of quality management system was analysed and compared with requirements of the ČSN EN ISO 9001 standard. Based on determined shortcomings, corrective measures were proposed. The measures related to process management and risk analysis were performed within the pactical part of this thesis.
15
Tian, Min [Verfasser]. "QoS integration in Web services with the WS-QoS framework / Min Tian". Berlin : Freie Universität Berlin, 2005. http://d-nb.info/1021667587/34.
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Tamura, Gabriel. "QoS-CARE : a reliable system for preserving QoS contracts through dynamic reconfiguration". Thesis, Lille 1, 2012. http://www.theses.fr/2012LIL10031/document.
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Le principal défi de cette thèse est de préserver de façon fiable la qualité de service (QoS) définie par contrats dans des systèmes logiciels à base de composants, ceci dans des conditions changeantes d'exécution du système. En réponse à ce défi, nous présentons deux contributions. La première est un modèle pour les applications logicielles à base de composants avec contrats de qualité de service et règles de reconfiguration définies par des graphes attribués typés. Ainsi, nous utilisons des modèles formels à l'exécution pour reconfigurer de manière fiable des applications logicielles de façon à préserver les contrats de QoS. Plus précisément, nous montrons la faisabilité d'exploiter des patrons de conception à l'exécution dans des boucles de reconfiguration tout en garantissant les niveaux de QoS attendues. Nous mettons en œuvre ce modèle formel par le biais d'une architecture à base de composants qui peut être utilisée comme une couche supplémentaire de la plateforme SCA, ceci afin de préserver les contrats de QoS.La seconde contribution est la caractérisation des propriétés d'adaptation pour évaluer les systèmes logiciels auto-adaptatifs de manière standardisée et comparable. De par leur nature, les mécanismes d'adaptation des systèmes logiciels auto-adaptatifs sont essentiellement des boucles de rétroaction telles que définies par la théorie du contrôle. Ainsi, pour les évaluer, il est nécessaire de ré-interpréter ces proprétés dans le domaine du logiciel. Nous définissons la fiabilité de la réalisation de notre modèle formel en termes de sous-ensemble des propriétés d'adaptation caractérisées, et nous montrons que ces propriétés sont garanties dans cette réalisationThe main challenge of this Thesis is to reliably preserve quality of service (QoS) contracts in component-based software systems under changing conditions of system execution. In response to this challenge, the presented contribution is twofold. The first is a model for component-based software applications, QoS contracts and reconfiguration rules as typed attributed graphs, and the definition of QoS-contracts semantics as state machines in which transitions are performed as software reconfigurations. Thus, we effectively use (formal) models at runtime to reliably reconfigure software applications for preserving its QoS contracts. More specifically, we show the feasibility of exploiting design patterns at runtime in reconfiguration loops to fulfill expected QoS levels associated to specific context conditions. We realize this formal model through a component-based architecture and implementation that can be used as an additional layer of SCA middleware stacks to preserve the QoS contracts of executed applications.The second contribution is the characterization of adaptation properties to evaluate self-adaptive software systems in a standardized and comparable way. By its own nature, the adaptation mechanisms of self-adaptive software systems are essentially feedback loops as defined in control theory. Thus, it results reasonable to evaluate them using the standard properties used to evaluate feedback loops, re-interpreting these properties for the software domain. We define the relibility of our formal model realization in terms of a subset of the characterized adaptation properties, and we show that these properties are guaranteed in this realization
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Fujikawa, Kenji. "A Study on QoS Guarantee, QoS Routing and Multicast on the Internet". 京都大学 (Kyoto University), 2000. http://hdl.handle.net/2433/151472.
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Horbach, Jan. "Dynamische Bandbreitenbeschränkung mit QoS". Master's thesis, Universitätsbibliothek Chemnitz, 2001. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-200101001.
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Diese Diplomarbeit beschäftigt sich mit der
"schleichenden Abschaltung" begrenzter
Netzzugänge bei Überschreitung eines vorgegebenen
Datenvolumens und der Anwendung dieser Technologie
im Chemnitzer Studentennetz. Nutzer, die bestimmte
Transfervolumina überschreiten, werden
schrittweise einer immer schlechter bewerteten
Verkehrsklasse zugeordnet, wo ihnen weniger
Bandbreite zur Verfügung steht. Dazu werden die
Möglichkeiten, die der Linux-Kern hinsichtlich
Quality of Service bietet, genutzt.
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Mbenza, Alexandre Seth da Silva. "Quality Manager System (QMS)". Master's thesis, Instituto Politécnico de Setúbal. Escola Superior de Tecnologia de Setúbal, 2019. http://hdl.handle.net/10400.26/31330.
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Relatório de projeto do Mestrado em
Informática de GestãoA evolução tecnológica a nível da indústria e de metodologias utilizadas torna imperativo que as organizações adotem novos mecanismos e que estas novas tecnologias reflitam uma maior eficiência para as mesmas. Neste contexto, as organizações apostam cada vez mais na gestão da qualidade, encarando-o como uma ferramenta eficaz para fazer face à competitividade nacional e internacional. Não menosprezam toda a atividade relacionada com a inovação, mas consideram que é fundamental uma base com qualidade, permitindo assim atingir patamares superiores. O presente relatório visa abordar a metodologia e o processo de implementação das normas internacionais a nível geral. O conhecimento adquirido ao longo do percurso profissional no desenvolvimento de um software, bem como em outras competências intrínsecas, permitiram idealizar o desenvolvimento de uma plataforma capaz de gerir e implementar um sistema de gestão de qualidade. com o intuito de que este seja capaz de evoluir e de ser mantido de forma organizada. Com a implementação da ISO 27001, neste contexto, e após a análise de soluções existentes no mercado e da estrutura de implementação e certificação das normas internacionais, surgiu a necessidade de apresentar uma solução que vise facilitar este mesmo processo e que também ajude na manutenção de um sistema de gestão. Para este desenvolvimento foi necessário efetuar um levantamento de alguns sistemas que já existiam nesta área, sendo que as soluções encontradas no mercado não satisfaziam a necessidade de um sistema de gestão de qualidade. Apesar destas permitirem gerir este tipo de sistemas de qualidade, não estão focadas no processo de implementação e certificação das ISO. Deste modo, o QMS4.0 tem como objetivo minimizar esta lacuna identificada e facilitar o processo interno das empresas.
Technological developments in industry and in the methodologies used make it imperative for organizations to adopt new mechanisms and new technologies and to reflect on greater efficiency. In this context, organizations are increasingly focusing on quality management, seeing it as an effective tool to address national and international competitiveness. They do not underestimate all innovation-related activity, but considering that, a quality base is fundamental, thus allowing to reach higher levels. This report aims to address the methodology and process of implementation of international standards at the general level. The knowledge acquired along the professional career in software development as well as in other intrinsic skills allowed us to idealize the development of a platform capable of managing and implementing a quality management system in order to be able to evolve and to develop. be kept in an organized manner. With the implementation of ISO 27001 in this context, and after the analysis of existing solutions in the market and the structure of implementation and certification of international standards emerged the need to present a solution that aims to facilitate this same process and that also helps in maintaining a system management. For this development, it was necessary to make a survey of some systems that already existed in this area, and the solutions found in the market did not satisfy the need for a quality management system. Although these allow the management of such quality systems, they aren’t focused on the ISO implementation and certification process. This QMS4.0 aims to minimize this identified gap and facilitate this internal process of companies.
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Roumani, Ali Mohamad. "QoS-based multicast routing". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0034/MQ52943.pdf.
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Grift, Werner. "Visualizing Qos in networks". Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019.1/17356.
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Thesis (MSc)--University of Stellenbosch, 2006.ENGLISH ABSTRACT: Network simulations generate large volumes of data. This thesis presents an animated visualization system that utilizes the latest affordable Computer Graphics (CG) hardware to simplify the task of visualizing and analyzing these large volumes of data. The use of modern CG hardware allows us to create an interactive system which allows the user to interact with the data sets and extract the relevant data in real time. We also present an alternate approach to the network layout problem, using Self Organizing Maps to find an aesthetic layout for a network which is fundamental to a successful network visualization. We finally discuss the design and implementation of such an network visualization tool.
AFRIKAANSE OPSOMMING: Netwerk simulasies genereer groot volumes data. Hierdie tesis stel voor ’n geanimeerde visualiseringwat gebruik maak van die nuutste bekostigbare rekenaar grafika hardeware om die visualisering van groot volumes data te vergemaklik. Die gebruik van moderne rekenaar grafika hardeware stel ons in staat om sagteware te skep wat n gebruiker in staat stel om met die data te werk. Ons stel voor ’n alternatiewe benadering om die netwerk se uitleg daar te stel, met die hulp van tegnieke wat gebruik word in die studie van neurale netwerke. Ons bespreek dan die ontwerp en implementering van so ’n netwerk visualisering program.
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Horbach, Jan. "Dynamische Bandbreitenbeschränkung mit QoS". [S.l. : s.n.], 2001. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB10047781.
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Farber, Dawn L. (Dawn Lee). "Multi-channel QRS detector". Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/10868.
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Tondello, Gustavo Fortes. "Especificação semântica de QoS". Florianópolis, SC, 2008. http://repositorio.ufsc.br/xmlui/handle/123456789/91511.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Ciência da ComputaçãoMade available in DSpace on 2012-10-23T23:47:03Z (GMT). No. of bitstreams: 1 259451.pdf: 1464324 bytes, checksum: f73443a4cdf02c0e6aa0420528c89c98 (MD5)
Este trabalho apresenta a ontologia QoS-MO que permite a especificação de características e requisitos de QoS para Web Services Semânticos ou Componentes de Software e pode ser facilmente utilizada para estender a OWL-S ou outras ontologias de descrição funcional de Componentes. As especificações de QoS modeladas a partir da ontologia QoS-MO podem ser utilizadas no projeto, desenvolvimento, publicação e descoberta de Web Services ou Componentes de Software. Um mecanismo de busca semântica de Web Services ou Componentes de Software foi especificado, voltado para a descoberta de Componentes que atendam a um conjunto definido de restrições de QoS, utilizando a ontologia QoS-MO e a linguagem de consulta SPARQL. Um protótipo deste mecanismo foi desenvolvido, contando tanto com uma interface de programação como uma interface Web. Os testes realizados demonstraram que o mecanismo proposto é viável e apresenta um desempenho aceitável e que a ontologia definida é capaz de expressar características de QoS complexas. A comparação com mecanismos de descoberta de Web Services de propostas similares demonstrou que a abordagem QoS-MO é mais simples e eficiente, pois não depende de nenhum algoritmo complexo para sua execução, apenas de um mecanismo de inferência simples e da linguagem SPARQL.
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Bumbál, Miroslav. "QoS v IP síti". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-217998.
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Master 's thesis deals about computer networks, which constitutes a global communication structure and play a very important role in today's society. The rapid development of Internet, the emergence of new multimedia applications and their increasing use of calls to the efficient functioning of the creation of such governance mechanisms of transmission, which are able to secure the required parameters. The thesis deals about the issue of quality of service (QoS) in IP networks. It presents the basic characteristics and requirements of these networks for the transmission of sensitive data by the quality of services, deals with the QoS definition, and describes the essential parameters to be followed to achieve the required quality of service in practical deployment. In addition, lists the various principles and options to ensure QoS in computer networks. Generally, it represents the Cisco 1841 router features and options to ensure quality of service in the network based on these routers. Practical thesis part provides two types of model IP networks, which were designed in order to verify the impact of service quality in real practice. Of the known methods to ensure QoS, which include a mechanism of Integrated services, Differentiated services, it focus its content about the Differentiated Services and the implementation of these in proposed network model. The last part of the work presents the results obtained by the impact of quality of service for the applications and their assessment.
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Kavan, Radovan. "QoS v systému UMTS". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-218026.
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This thesis treats of QoS (Quality of Service) in UMTS system. The term quality of service is frequently used, recently, however not only in computer networks, but also more and more in mobile networks also. Present system of 2nd generation (2G) GSM enables only limited exploitation of QoS function. System UMTS is a system of 3rd generation (3G) already and contains quality of service in greater measure which is ensured with number of algorithms and functions. Individual QoS functions enable effective utilization of radio interface, support maintenance of planned coverage and offer high spectral efficiency. Functions that cater to quality of service are called RRM functions (Radio Resource Management). There exist five basic functions in UMTS system that are Admission control (AC), Power control (PC), Load control (LC), Handover control (HC) and Packet scheduler (PS). These functions are responsible for control of network access, control of power, control of network load, control of handover and packet (bit rate) scheduling. Last three functions are usually collectively designated as Congestion control, control of network overload. UMTS layer model, differentiation of services, traffic classes and 3GPP concept are also discussed. In thesis the attention is piad to Admission control algorithm – control of network access – in the uplink direction and to different ways of load (in the cell) modeling. Individual approaches are simulated in MATLAB. A possibility of using algorithm in the real system is discussed in conclusion.
27
Kalina, Tomáš. "QoS v síti VŠE". Master's thesis, Vysoká škola ekonomická v Praze, 2012. http://www.nusl.cz/ntk/nusl-164040.
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The diploma thesis is focused on analysis and deployment of Quality of Services (QoS) in a computer network of The University of Economics in Prague (VŠE). The thesis describes the main QoS technologies focusing on technology Diffserv and its deployment with using available network devices in computer network of VŠE. In thesis the needs of network services and protocols for quality of services with division into different classes of services according to priority are discussed. The thesis explains the benefits and drawbacks of deploying QoS in the environment of VŠE with regard to wired and wireless network. In the practical part recommendations are applied to the production network and subsequently the benefits of modification are evaluated.
28
Boughanmi, Najet. "Conception conjointe des systèmes contrôlés en réseaux sans fil". Thesis, Vandoeuvre-les-Nancy, INPL, 2011. http://www.theses.fr/2011INPL021N/document.
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Le cadre de cette thèse est l'étude des systèmes contrôlés en réseau sans fil (SCRSF) qui utilise la technologie IEEE 802.15.4. Le premier objectif est d'étudier la pertinence de l'utilisation du réseau de type IEEE 802.15.4 pour les SCRSF puis de proposer et d'évaluer des mécanismes pour garantir la Qualité de Service (QdS) offerte par le réseau au système contrôlé. Nous analysons l'utilisation des slots temporels réservés (GTS) dans le cadre des SCRSF et les contraintes qui en découlent. De plus, nous proposons des mécanismes de gestion de la QdS avec priorité aussi bien pour le mode avec balise que pour le mode sans balise du protocole IEEE 802.15.4. Ces propositions ont été validées par des simulations et une partie de manière analytique. Notre deuxième objectif est de concevoir, d'une manière conjointe, les SCRSF pour pouvoir régler en ligne la QdS offerte par le réseau en fonction de la Qualité de Contrôle (QdC) du système contrôlé. Nous proposons des protocoles d'adaptation en ligne de la QdS du réseau qui prennent en compte la QdC du système contrôlé. Ces protocoles ont été validés par simulations et une implémentation réelle de chacun d'eux est proposéeIn this thesis, we study wireless networked control systems (WNCS) which use the IEEE 802.15.4 technology. The first objective is to study the pertinence of the use of the IEEE 802.15.4 for the WNCS, then to propose and evaluate QoS management mechanisms which guarantee the Quality of Service (QoS) offered by network to the controlled system. We analyse the use of the guaranteed temporel slots (GTS) for WNCS and in which conditions it is possible. We propose QoS management mechanisms with priority for both the beacon enabled mode and the non-beacon enabled mode of the IEEE 802.15.4 protocol. These proposals are validated through simulations and partially with analytical approach. The second objective is to design the WNCS so that the QoS offered by the network is adated online depending on the Quality of Control (QoC) on the controlled system. We propose QoS online adaptation protocols which take as parameter the QoC of the system. These protocols are validated through simulations and a realistic implementation of them is proposed
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Bakhsh, Helen Jameel H. "ATL-QoS : an adaptive trust-aware location-based framework for achieving QoS in MANETs". Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/atlqos-an-adaptive-trustaware-locationbased-framework-for-achieving-qos-in-manets(d0c5f89e-5576-4a91-a601-aa4aca60e15a).html.
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Mobile ad hoc networks (MANETs) have gained increasing attention from industry for their potential applications. MANETs allow devices to communicate in areas with no pre-existing communication infrastructure. In MANETs, node mobility leads to dynamic changes in network topologies and fluctuations in network available bandwidth. The lack of infrastructural support means that communication nodes need to collaborate among themselves functioning as routers (intermediate nodes) for other nodes. This places additional processing and communication loads onto the communication nodes and opens up doors to more active attacks by intermediate nodes. It is also worth noting that mobile nodes are typically battery powered, and they are more restrictive in terms of storage space and processing capabilities than their wired counterpart. These MANET features indicate that achieving QoS in MANETs should be done in the most cost-effective manner. In this thesis, a novel Adaptive Trust-aware Location-based (ATL-QoS) framework is proposed. The ATL-QoS framework can harvest fluctuating available bandwidth in the underlying network to deliver high priority traffic in various network conditions. The novelty of the framework lies in that it uses single path and multiple path deliveries and packet duplication over multiple path, in an adaptive manner, in an attempt to increase high priority traffic delivery with minimum bandwidth overhead costs. The framework handles low and high priority traffic in a differential manner. To implement these ideas, two novel ATL-QoS components are designed: (1) a Trust-Aware Dynamic Location-based (improved version) (TADLV2) multiple path discovery protocol and (2) a path Selection, traffic Allocation, and path Verification (SAV) solution. The TADLV2 protocol is designed to discover multiple path between a pair of communication nodes with minimum bandwidth overheads, we first designed TADL protocol and then an improved version of TADL, TADLV2. The SAV solution is designed to increase high priority traffic delivery success. These ATL-QoS framework ideas are implemented and evaluated using the NS-2 simulation and compared against the most relevant protocol in the literature. The simulation study shows that ATL-QoS outperforms the relevant protocol in terms of reducing routing overheads and increasing packet delivery ratios. These enhancements making ATL-QoS more effective in providing QoS.
30
Porwal, Rupesh. "Adaptive Selective Flooding Qos Routing". Thesis, Indian Institute of Science, 2002. http://hdl.handle.net/2005/51.
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The routing strategy used in today's Internet is best-effort service, where all data packets are treated equally. This type of service is not suited for applications such as video conferencing, and video on demand, that requires the availability of certain resources (such as bandwidth) to be guaranteed for them to function properly. The routing in this context, called Quality-of-Service (QoS) Routing, is the problem of finding suitable paths that meet the application's resource requirements.
The majority of proposed QoS routing schemes operate by maintaining the global state of the network, and using this knowledge to compute the QoS route. However, all these schemes suffer from the inherent drawback of scalability, because of the need for each node to collect state information about the complete network. The other type of QoS routing schemes do not maintain network state information, but instead flood the network with QoS connection establishment requests. This type of scheme suffers from excessive message overhead during QoS connection establishment.
In this thesis, we present a new QoS routing algorithm that is a combination of the above-mentioned two schemes (i.e., global state and flooding based). The algorithm aims at minimizing the message overhead associated with these two schemes and still maintaining the positive aspects of both of them. The basic idea of the algorithm is: to reach to a destination, the path(s) will always pass through a specific set of intermediate nodes. The algorithm discovers such intermediate nodes (limited by a hop count threshold value needed to reach there). When a QoS connection request arrives at a node, it selects the feasible path leading to the intermediate node for the requested destination. The QoS connection establishment message (or routing message) is forwarded along this path. When the message arrives at the intermediate node, the further path is decided through same logic. To decide the path that leads to the intermediate node, the algorithm maintains the link state related to these intermediate nodes, and link state updates are restricted only with regard to these intermediate nodes. Because of this restriction in link state updation, one has less message overhead, compared to the global state based routing scheme. Further, the algorithm tries to group these intermediate nodes in such a way that the routing message need be sent to only one of the grouped intermediate nodes, and still makes sure that all the possible paths are covered. Therefore, one has a reduced message overhead because of grouping.
31
Hao, Fang. "Scalability techniques in QoS networks". Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/9175.
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Korkmaz, Turgay. "QoS routing in packet networks". Diss., The University of Arizona, 2001. http://hdl.handle.net/10150/289740.
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The current best-effort service of the Internet is not sufficient to meet the demands of emerging real-time network applications (e.g., video conferencing, Internet telephony). This has motivated the development of new networking technologies (e.g., Intserv, Diffserv, MPLS) that are geared towards providing quality-of-service (QoS) guarantees (e.g., bandwidth, delay, fitter, reliability) to prospective flows. Various aspects of these technologies are being extensively investigated in the research community. In this dissertation, we focus on the routing aspect, with the objective of providing scalable and computationally efficient solutions. The QoS routing problem involves two tasks: (a) capturing and disseminating the state information of the underlying network; and (b) using this information to compute resource-efficient constrained paths. In the presence of multiple constraints (QoS link parameters), these two tasks become notoriously challenging. We investigate several key issues in QoS routing and discuss how to integrate the provided solutions into evolving state-dependent and hierarchical routing protocols (e.g., PNNI and QoS-extended OSPF). First, we develop a hybrid mechanism based on both flooding and tree-based broadcasting for reliable and efficient dissemination of dynamic link-state parameters, such as bandwidth. Second, we present a scalable, source oriented state aggregation methodology for hierarchical networks. Third, we introduce several heuristics and approximation algorithms for path selection under multiple QoS constraints. Fourth, we consider the path selection problem under inaccurate (probabilistically modeled) state information, and provide a heuristic for a special yet important case of this problem, namely, routing under bandwidth and delay constraints. Finally, we evaluate the performance of the proposed methods through simulations.
33
Walsh, S. M. "Packet scheduling for wireless QOS". Thesis, Queen's University Belfast, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487465.
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Since their arrival in the late 90's wireless packet schedulers have sought to seamlessly re-apply the concepts of fair queuing (FQ) algorithms (traditionally employed in wire-mediated communications) to provide fairness, throughput and delay gutUlUltees to individual sessions in the wireless environment. What has militated against a smooth transition in this regard is the presence of unpredictable bursty location-dependent channel errors due to fading on the wireless channel. The approach generally employed by wireless schedulers for minimizing the effects of channel errors is to use a compensation policy. Compensation has traditionally been applied in two -ways: (a) penalizing sessions that have utilized extra bandwidth gained from the loss ofanother session and (b) reserving a fraction ofthe system bandwidth. This dissertation presents a novel scheduling approach that employs multiple sources of compensation so that an emphasis is placed on allowing sessions to recover as quickly as possible from channel errors, while at the same time preserving the guarantees ofother sessions in the system. Two crucial factors are identified that influence how wireless packet scheduling should be performed namely the channel bandwidth and the traffic variation. In order to better understand the dynamics ofthese two driving forces, this dissertation quantifies and analyzes the behavior of each ofthese parameters in typical real-world worst-case scenarios. Through investigating the nature ofthese two aspects ofthe network, a number of conclusions are drawn on how certain wireless scheduling procedures should be implemented. In particular the recording of lost service and the application of compensation are significantly affected by the nature of these two system attributes. It is shown that wireless scheduling algorithms must incorporate far more system knowledge than what was traditionally required for the wired environment. This research proposes a novel traffic profile and priority based wireless fair queuing (TPP-WFQ) scheduling algorithm that is heavily reliant on system functions that perform; bandwidth management, weight adjustment, link adaptation, queue management, traffic classification and traffic monitoring. Several novel attributes are introduced with the TPP-WFQ algorithm, these include: (i) A novel lag/lead calculation model that makes use of knowledge of the traffic profile to accurately measure the amount of service lost and gained for different sessions when an error occurs. (ii) A novel compensation approach that adopts five sources ofcompensation. This allows for a fast recovery time which is the fundamental attribute that has motivated extensive research in the field of wireless scheduling. (iii) A classbased weight adjustment function that manages the weights for all sessions in the system when partial errors occur on channels due to link adaptation. (iv) A priority-based compensation approach that ensures that compensatory resources are prioritized according to the class oftraffic being compensated. This ensures that delay-sensitive sessions recover more quickly than delay-tolerant ones. Detailed simulations incorporating multiple worst-case scenarios illustrate that these areas of novelty enable TPP-WFQ to perform significantly better than selected high ranking schedulers presented in the literature at providing strong QoS to sessions in an error prone environment. In particular, we demonstrate that TPP-WFQ allows delay-sensitive real-time sessions to becom~ more resilient to poor channel conditions.
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Martins, José Carlos Ferreira da Silva. "QoS em servidores HTTP Apache". Master's thesis, Universidade de Évora, 2015. http://hdl.handle.net/10174/17549.
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Os serviços baseados na Internet têm registado um crescimento contínuo e acelerado nos
últimos anos, dependendo o seu sucesso, em larga medida, da qualidade de serviço prestada.
A sociedade moderna tornou-se fortemente dependente da Internet e dos vários serviços nela
disponibilizados.
Nesta dissertação é abordado o problema da qualidade de serviço em servidores HTTP, com
particular ênfase no servidor HTTP Apache. Neste trabalho, é definido e implementado
um sistema original de controlo em cadeia fechada de QoS, baseado nas metodologias da
teoria de controlo, demonstrando-se a sua robustez, estabilidade e capacidade para gerir
os recursos de forma dinâmica. Por fim, é comprovada a capacidade do sistema realizar a
diferenciação de serviço (DiffServ) entre duas classes de sítios: Premium e Outros. Esta
qualidade é comprovada para os objetivos erro nulo, rejeição de perturbações e seguimento
de referência; Abstract:
QoS for Apache HTTP server
Internet-based services have registered a continuous and rapid growth in recent years, depending
their success to a large extent on the provided quality of service. Modern society
has become heavily dependent on the Internet and the various services it provides.
This thesis addresses the issue of quality of service in HTTP servers, with particular emphasis
on the Apache HTTP server. In this work, a closed-loop system with QoS, based on
control theory methodologies, is defined and implemented. The proposed system robustness,
stability and ability to manage resources dynamically is shown. Finally, it is confirmed
the system’s ability to provide differentiated services (DiffServ) between two classes of sites:
Premium and Others. This quality is proven to the objectives regulatory control, disturbance
rejection and time-varying reference.
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Adámek, David. "Implementace QoS v přístupové síti". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217611.
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This diploma thesis deals with computer networks which play a key role in present society. More and more demands are placed on these networks (especially on quality of services and throughput) because of fast-growing developement of services such as voice and video real-time transmissions. All the packets in typical Ethernet networks are equal. Therefore it is sometimes impossible for the application to maintain required throughput speed of a network. For this case it is useful to take some mechanisms into the consideration. These mechanisms (sometimes called QoS) are able to distinguish different types of transmissions and traffic, analyze them and then prioritize them according to some pre-defined set of rules. The most famous mechanisms are Integrated Services and Differentiated Services. The implementation of Differentiated Services is the goal of this thesis.
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Fabricius, Marián. "Zajištění QoS v UMTS síti". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-218065.
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Diploma thesis deals with assign and distribution quality of service in mobile UMTS telecommunication networks. The project consists of two parts, theoretical and practical. Theoretical part of the project is focused to familiarize with functionality of the UMTS network with the main aspect at admission mechanism in radio part of the network as well as quality of service assign mechanisms according to service demands within core network of UMTS. Practical part of the project is given to simulation program OPNET Modeler and its capabilities in network design and testing various parameters of UMTS network with implementation quality of service mechanism. As the asset of diploma thesis becomes designed functional prototype of UMTS network with various options for individual settings user equipment as well as fixed mobile networks nodes.
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Kolmačka, Jan. "Zajištění QoS v bezdrátových sítích". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218563.
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The diploma thesis gives the overall information about the field of wireless networks of standards 802.11 and Quality of Service (QoS). The practical measurements describe the reactions of multimedia dataflows in the networks 802.11a/b/g/n. The individual standards, offered services, access methods and the network architecture are analyzed in the theoretical part. In the following part there is written about QoS and its basic parameters. Moreover, the standard 802.11e and the question of QoS in the wireless networks are explained in a detailed way. The first part of the practical measurement is focused on the networks 802.11b/g/n. All main network statistics are measured when using the wireless stations and routers. The projection and implementation of the wireless network in the Opnet Modeler is included in the next part. The individual simulations WLAN in the Opnet Modeler are comparing the networks 802.11a/b/g. The analysis of the key QoS statistics is undertaken; the measured data are clearly displayed in the charts and schemes. The interpreted results are concluded and justified.
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Figurny, Roman. "Podpora QoS v MANET sítích". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219468.
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The theoretical part of Master's thesis has been dealing with issues of MANET networks, issues of providing quality of services in MANET networks and analysis of various implementations of quality of services in these networks. At the start of the practical part of this thesis was described modified OLSR process model with support of quality of services. In simulation program OPNET Modeler was designed a topology of MANET network, firstly was run a simulation of this network without any support of quality of services and then was run a simulation with support of quality of services. The results of these simulations were analyzed, compared and graphically interpreted. In the next part of this thesis was designed a real MANET network with OLSR support. OLSR network communication was captured with the use of Wireshark. In the last part of this thesis was firstly described a meaning and functions of plugins in OLSR implementation and then was developed a plugin which is responsible for sending messages which contain a state of the links between nodes of MANET networks.
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Filla, Michal. "Návrh QMS v malé organizaci". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-228038.
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This Diploma thesis is engaged in implementation of quality management system in a small organization. In this thesis is closely described quality management system, its advantages and rules. There was made an entry analysis and documentation was checked and completed.
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Husák, Adam. "Zlepšení QMS organizace aplikací DMAIC". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230527.
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The aim of this master´s thesis is to design an action to improve of selected process Design and development through DMAIC application. The thesis is focused on identifying the problem, finding the cause and following design of improves leading to eliminate problems. This improves will enable the company to achieve time savings during the process and reduce a risk of orders. Result of this is effective operation in the process.
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Heger, Jan. "Návrh QMS v malé organizaci". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230994.
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The thesis suggests quality management for small organizations and focuses on its implementation, using the DMAIC methodology in accordance with ČSN EN ISO 9001. First, a chosen small organization will be analysed; next, the key processes will be defined and their setting in accordance with ČSN EN ISO 9001 provided.
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Islam, Mohammad Kamrul. "QoS In Parallel Job Scheduling". The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1218566682.
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Adepu, Sagarika. "Qos Aware Service Oriented Architecture". Thesis, University of North Texas, 2013. https://digital.library.unt.edu/ark:/67531/metadc500032/.
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Service-oriented architecture enables web services to operate in a loosely-coupled setting and provides an environment for dynamic discovery and use of services over a network using standards such as WSDL, SOAP, and UDDI. Web service has both functional and non-functional characteristics. This thesis work proposes to add QoS descriptions (non-functional properties) to WSDL and compose various services to form a business process. This composition of web services also considers QoS properties along with functional properties and the composed services can again be published as a new Web Service and can be part of any other composition using Composed WSDL.
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Dang, Xiaoyu. "Space-Time Shaped Offset QPSK". International Foundation for Telemetering, 2008. http://hdl.handle.net/10150/606190.
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ITC/USA 2008 Conference Proceedings / The Forty-Fourth Annual International Telemetering Conference and Technical Exhibition / October 27-30, 2008 / Town and Country Resort & Convention Center, San Diego, CaliforniaThis paper describes the use of orthogonal space-time block codes to overcome the performance and complexity difficulties associated with the use of Shaped Offset QPSK (SOQPSK) modulation, a ternary continuous phase modulation (CPM), in multiple-input multiple-output telemetry systems. The orthogonal space-time block code is applied to SOQPSK waveforms in the same way it would be applied to symbols. The procedure allows the receiver to orthogonalize the link. The main benefits of this orthogonalization are the easy realization of the transmit diversity for the offset-featured SQOSPK, and the removal of the noise correlation at the input to the space-time decoder and the elimination of I/Q interference when space time orthogonalization is applied to the symbol level.
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Souihi, Sami. "Mise en oeuvre d’une plateforme de gestion et de dissémination des connaissances pour des réseaux autonomiques". Thesis, Paris Est, 2013. http://www.theses.fr/2013PEST1193/document.
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La croissance du réseau Internet, l'émergence de nouveaux besoins par l'avènement des terminaux dits intelligents (smartphones, tablettes tactiles, etc.) et l'apparition de nouvelles applications sous-jacentes induisent de nombreuses mutations dans l'usage de plus en plus massif des technologies de l'information dans notre vie quotidienne et dans tous les secteurs d'activités. Ces nouveaux usages ont nécessité de repenser le fondement même de l'architecture réseau qui a eu pour conséquence l'émergence de nouveaux concepts basés sur une vue "centrée sur l'usage" en lieu et place d'une vue "centrée sur le réseau". De fait, les mécanismes de contrôle du réseau de transport doivent non seulement exploiter les informations relatives aux plans de données, de contrôle et de gestion, mais aussi les connaissances, acquises ou apprises par inférence déductive ou inductive, sur l'état courant du réseau (trafic, ressources, rendu de l'application, etc.) de manière à accélérer la prise de décision par les éléments de contrôle du réseau. Les travaux faits dans le cadre de cette thèse concernent ce dernier aspect et rejoignent plus généralement ceux tournés sur les réseaux autonomiques. Il s'agit dans cette thèse de mettre en oeuvre des méthodes relatives à la gestion, à la distribution et à l'exploitation des connaissances nécessaires au bon fonctionnement du réseau de transport. Le plan de connaissances mis en oeuvre ici se base à la fois sur l'idée de développer une gestion au sein d'une structure hiérarchisée et adaptative où seuls certains noeuds sélectionnés sont en charge de la dissémination des connaissances et l'idée de relier ces noeuds au travers d'un ensemble de réseaux couvrants spécialisés permettant de faciliter l'exploitation de ces connaissances. Comparée aux plateformes traditionnellement utilisées, celle développée dans le cadre de cette thèse montre clairement l'intérêt des algorithmes élaborés au regard des temps d'accès, de distribution et de partage de charge entre les noeuds de contrôle pour la gestion des connaissances. A des fins de validation, cette plateforme a été utilisée dans deux exemples d'application: le Cloud computing et les smartgridsThe growth of the Internet, the emergence of new needs expressed by the advent of smart devices ( smartphones, touchpads , etc. ) and the development of new underlying applications induce many changes in the use of information technology in our everyday life and in all sectors. This new use that match new needs required to rethink the foundation of the network architecture itself, which has resulted in the emergence of new concepts based on a "use-centeric" view instead of a "network-centric" view. In fact, the control mechanisms of the transmission network must not only exploit the information on data, control and management planes, but also the knowledge acquired or learned by inductive or deductive inference on the current state of the network (traffic, resources, the rendering of the application, etc.) to accelerate decision making by the control elements of the network. This thesis is dealing with this latter aspect, which makes it consistent with work done on autonomic networks. It is about conceiving and implementing methods for the management, distribution and exploitation of knowledge necessary for the proper functioning of the transmission network. The knowledge plane that we implemented is based on both the idea of developing a management within an adaptive hierarchical structure where only some selected nodes are responsible for the dissemination of knowledge and the idea of linking these nodes through a spanning set of specialized networks to facilitate the exploitation of this knowledge. Compared to traditionally used platforms, the one developed in this thesis clearly shows the interest of the developed algorithms in terms of access time, distribution and load sharing between the control nodes for knowledge management. For validation purposes, our platform was tested on two application examples : Cloud computing and smart grids
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Frikha, Ahmed. "On providing Qos and reliability for telecommunication networks : multi-domain Qos routing and multicast reliability". Rennes 1, 2012. http://www.theses.fr/2012REN1S067.
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Dans cette thèse, nous étudions deux problèmes majeurs dans les réseaux de télécommunications actuels. Tout d'abord, nous étudions le problème de la fourniture de la qualité de service (QoS) pour les nouvelles applications dans des réseaux multi-domaines. Précisément, le problème de calcul de chemins inter-domaine et multi-contrainte (ID-MCP) est profondément étudié dans la première partie de cette thèse. Dans la deuxième partie, nous étudions la fiabilité des communications dans les réseaux, qui est essentielle pour les services à contraintes strictes. Plus précisément, nous abordons le problème de la garantie de fiabilité des communications multicast. En effet les conséquences d'une panne d'un nœud ou d'un lien dans ce cas d'étude est grave puisque plusieurs destinations peuvent être déconnectées simultanément à la suite d'une seule panne. L'objectif de la première partie est de trouver des nouvelles approches qui permettent de résoudre le problème ID-MCP (inter-domain multi-constrained path computation problem), tout en respectant les politiques des opérateurs des réseaux, à savoir préserver la confidentialité des informations de routage et l'autonomie des domaines. Nous proposons trois nouveaux algorithmes basés sur les éléments de calcul de chemins (PCEs), algorithmes nommés respectivement: ID-PPPA, ID-MEFPA et HID-MCP. Les deux premiers algorithmes utilisent le pré-calcul qui permet de réduire le temps de calcul tout en maintenant un taux de succès élevé. Le troisième algorithme est basé sur un calcul hybride qui bénéficie à la fois des avantages du pré-calcul et du calcul à la demande. L'algorithme HID-MCP utilise des mécanismes de retour en arrière (crankback) pour améliorer le taux de succès global. Les performances de nos algorithmes proposés sont prouvées avec précision par des études analytiques et des simulations. L'objectif de la deuxième partie est de trouver des structures de protection des nœuds et des liens adaptées à la diffusion multicast. Comme le temps de restauration est un critère important dans le processus de reprise de routage (recovery), nous proposons l'étude de la protection des communications multicast au niveau de la couche optique DWDM. Une nouvelle génération de p-cycles adaptés à la structure de diffusion multicast et aux contraintes imposées par les réseaux tout-optiques, est proposée dans cette partie. Nous proposons également trois nouveaux algorithmes pour la protection des nœuds et des liens dans un trafic multicast dynamique, algorithmes nommés respectivement CCHN, NPCC et NPCC-SSC. Le premier algorithme utilise un ensemble de p-cycles candidats bien sélectionnés afin de réduire le temps de calcul et d'optimiser l'utilisation de la bande passante. Différentes approches pour la sélection des ensembles de p-cycles candidats sont étudiées. Le deuxième algorithme NPCC étend le concept de protection des nœuds avec les p-cycles pour une structure de diffusion multicast. Le troisième algorithme étend notre algorithme NPCC pour résoudre les contraintes imposées par les réseaux tout-optiques, telles que le nombre limité de commutateurs optiques capables de splitter un signal lumineux et la contrainte de continuité de la longueur d'onde. Les simulations prouvent que nos algorithmes peuvent assurer une bonne utilisation des ressources ainsi qu'une faible probabilité de blocage tout en réduisant le temps de calculIn this thesis, we study two major problems of today’s telecom networks. First, we study the problem of providing Quality of Service (QoS) guarantees for IP-based services in multi-domain networks. Precisely, the Inter-Domain Multi-Constrained Path (ID-MCP) computation problem is deeply investigated in the first part of this thesis. Second, we study networks reliability, which is essential for many services, namely mission-critical services. Specifically, we address the problem of ensuring reliable multicast communications. Indeed, the consequences of a node or link failure are dramatic in this case of study as multiple destinations could be disconnected simultaneously. The objective of the first part is to find new schemes that enable solving the ID-MCP problem while respecting the operators policies, namely preserving the routing information confidentiality and the autonomy of the domains. We propose three new algorithms based on the Path Computation Element (PCE) framework, named respectively : ID-PPPA, ID-MEFPA and HID-MCP. The first two algorithms employ a pre-computation scheme that allows the computational time to be reduced while maintaining a good acceptance rate of the requests. The third algorithm is based on a hybrid computation scheme that takes advantages from the pre-computation and the on-demand computation. The HID-MCP employs crankback mechanisms to improve the global success rate. Performances of our proposed algorithms are accurately proven through both analytical studies and simulations. The objective of the second part is to find node and link protection structures suitable for multicast diffusion. As the restoration time is a crucial criteria in the recovery process, we address the reliability of multicast communications at the DWDM optical layer. A new generation of p-cycles adapted for multicast diffusion structures as well as the constraints imposed by all-optical networks, is proposed in this part. We also proposed three new algorithms for node and link failure recovery in dynamic multicast traffic, named respectively CCHN, NPCC and NPCC-SSC. The first algorithm uses a set of well-selected candidate p-cycles in order to reduce the computational time and achieve a significant bandwidth saving. Different approaches for selecting the candidate p-cycle sets are investigated. The second algorithm, NPCC, extends the node protection concept of p-cycles for multicast traffic. The third algorithm extends our NPCC algorithm to deal with the constraints imposed by all-optical networks, such as sparse light-splitting and wavelength continuity constraints. Simulation results prove the efficiency of our algorithms in terms of resource utilization, blocking probability and the computational time
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Zedníček, Vlastimil. "Detekce QRS založená na vlnkové transformaci". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220878.
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This thesis deals with implementation of detector QRS complex with use of wavelet transform. The first part is focused on formation and possibility to measure cardiac activity. The other part of thesis we will familiarise with the different possibilities of detection QRS complex and we intimately focus on wavelet transform that will be used for a project of detection QRS complex. The practical part of thesis focuses on the project of detector in programming language Matlab and his different setting. This projected detector has been tested with CSE database. Achieved results of projected detector are evaluated with the results of others authors.
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Bereketli, Alper. "On Qos Multicast Routing Routing Protocols". Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606446/index.pdf.
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Multicasting is a technique used for distributing data packets from one or more sources to a set of receivers on interconnected networks. Currently developing network applications bring specific quality of service (QoS) requirements like bounded delay, minimum bandwidth, and maximum data loss rate. Providing the required quality of service addresses routing and resource reservation concepts. In this study, a literature survey is carried out on traditional and QoS multicast routing protocols, and the need for QoS routing protocols is investigated. QoS multicast routing protocols are classified and compared according to their multicast tree construction and resource reservation approaches. Two QoS protocols, QROUTE and QMBF, are selected, and their performances are experimentally compared using the network simulation tool Network Simulator-2 (ns-2). The objective of the simulations is to compare the QoS routing algorithms and their tree construction efficiencies. The first contribution of the thesis is the survey and classification of traditional and QoS multicast routing protocols. Another contribution is the ns-2 implementation of two QoS multicast routing protocols. The final contribution of the thesis is the performance evaluation of the recent protocols from a different perspective.
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Al-Dalati, Issam. "Enhanced QoS in Wireless Certified USB". Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/19966.
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Our study investigates the performance of the WUSB standards and compares it to the Wimedia Standard. To the best of our knowledge, no technical contributions exist in the open literature at present simulating WUSB and its performance. The study showed that WUSB can achieve better throughput when bursting is enabled at the maximum burst size and it provides more accurate timing control of device activity than using the standard facilities of the WiMedia MAC. Our study also addresses protocol extensions and improvement to the original WUSB standard to support better Quality of Service (QoS). First improvement enables a di erent reservation mechanism along with contention based access to support higher priority security and medical system monitoring applications. Second improvement enables the host device to use an adaptive packet loss technique to change the packet size dynamically during the data transmission to achieve packet loss less than 10%. Third improvement enables redundancy in the cluster by adding a backup host to prevent mobility failures and changes. This backup host is chosen by a prede ned cost weighting function.
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Zukauskas, Andrius. "QPM Devices in KTA and RKTP". Doctoral thesis, KTH, Laserfysik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-139475.
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Even though KTiOPO4 (KTP) is considered to be one of the best nonlinear materials for quasi phase matched (QPM) frequency conversion in the visible and the near-infrared spectral regions, its use is often limited by poor material homogeneity, high ionic conductivity, a considerable linear absorption and photochromatic damage. On the other hand, the improved material homogeneity and the lower ionic conductivity of bulk Rb-doped KTP (RKTP) make this material an ideal alternative for fabrication of fine-pitch QPM gratings, while the arsenate isomorph KTiOAsO4 (KTA) promises a better performance in the green spectral region and adds the advantage of a wider transparency window in the infrared. Unfortunately, the available studies on these materials are limited and unable to answer the question whether RKTP and KTA are feasible alternatives to KTP in terms of periodic poling and optical performance. The optical performance of the QPM devices depends on the periodic poling quality, therefore, a detailed comprehension of domain-grating formation in the KTP isomorphs is highly desired. The goals of this thesis were to gain a better understanding of the periodic poling process in the KTP isomorphs, in order to study the specifics of ferroelectric domain engineering in KTA and RKTP, and to evaluate the optical performance of these isomorphs. Fine-pitch periodically poled structures were engineered both in KTA and RKTP crystals. It was demonstrated that QPM gratings with excellent quality and with periods as short as 8.49 μm can be fabricated in KTA crystals. Comparative transmission studies have shown that periodically poled KTA (PPKTA) crystals can be superior to KTP for QPM second harmonic generation in the visible spectral region due to lower linear absorption. It was also demonstrated that RKTP is a superior alternative to KTP for high-quality QPM grating fabrication. A consistent room-temperature periodic poling of 5 mm thick RKTP crystals with a period of 38.86 μm has been achieved. The obtained large aperture periodically poled RKTP (PPRKTP) crystals showed an outstanding QPM grating uniformity and excellent optical performance in optical parametric oscillator (OPO) applications. Moreover, it was shown that RKTP is less susceptible to blue-induced infrared absorption than KTP. Finally, a novel and a relatively simple method for self-assembling quasi-periodic sub-μm scale ferroelectric domain structure in RKTP crystals has been presented. It was shown that, after treatment in aqueous KOH/KNO3 solution, periodic poling of RKTP with planar electrodes resulted in one-dimensional ferroelectric domain structure with an average periodicity of 650±200 nm, extending over the whole 1 mm thick crystal. Such self-assembled structures in RKTP were used to demonstrate 5th order non-collinear QPM backward second harmonic generation.QC 20140114