622 research outputs found
From Consilium to Advice: A Review of the Evaluation and Related Literature on Advisory Structures and Processes
No full textBaizerman, Michael; Fink, Alexander; VeLure Roholt, Ross. (2012). From Consilium to Advice: A Review of the Evaluation and Related Literature on Advisory Structures and Processes. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/169820
Symptom burden and health-related quality of life in cancer survivors undergoing hyperbaric oxygen therapy for pelvic late radiation tissue injuries : A mixed-methods study
No full textKurativ strålebehandling for kreft kan føre til alvorlige vevsstråleskader (LRTI). Det finnes imidlertid begrenset kunnskap om bekkenkreft-overleveres LRTI symptomer, psykisk belastning og helse-relatert livskvalitet (HRQOL). Hyperbar oksygenbehandling (HBOT) er en adjuvant, men lite studert, behandling for LRTI symptomer. Derfor var det overordnede formålet med denne studien å få økt forståelse av symptombyrde og HRQOL hos kreft-overlevere som gjennomgår HBOT for stråleskader i bekkenet.
Pasienter som ble inkludert i studien ble rekruttert fra kreft-overlevere med bekken LRTI henvist til Norsk Nasjonal Enhet for Planlagt Hyperbar Oksygenbehandling. Her ble deltakerne behandlet med HBOT i enmannstrykkammer, og pustet rent oksygen ved et trykk på 2.4 atmosfære absolutt i 90 minutter en gang daglig i seks uker.
En mixed-metode med et forklarende sekvensielt forskningsdesign ble benyttet. Data ble samlet inn sekvensielt ved hjelp av selvrapporterte spørreskjemaer på baseline (T1), ved avslutning HBOT (T2) og ved seks måneders oppfølging (T3), og dybdeintervju ved avslutning HBOT.
Gjennom en kvantitativ tilnærming og tverrsnittsdesign studerte vi i Artikkel 1 symptombyrde, psykisk belastning og HRQOL hos kreft-overlevere med etablerte bekken LRTI symptomer sammenlignet med normpopulasjoner, og sammenhengen mellom disse faktorene før oppstart av HBOT. Totalt 107 deltakere (gjennomsnittsalder 64 år, 53% menn) ble inkludert. Sammenlignet med normpopulasjonen rapporterte deltakerne mer urinsymptomer (gjennomsnitt 68.7 vs. 89.5; p=.00; d=1.4) og tarmsymptomer (gjennomsnitt 62.5 vs. 92.4; p=.00; d=2.7), økt psykisk belastning (gjennomsnitt 13.4 vs. 10.3; p=.00; d=0.6), og generelt dårligere HRQOL (gjennomsnitt 54.9 vs. 71.2; p=.00; d=0.7). Høyere symptombyrde og høyere nivå av psykiske plager var assosiert med lavere HRQOL (r2=46%), men psykiske plager modererte ikke symptomenes påvirkning på HRQOL.
Gjennom en kvalitativ metode og et fenomenologisk-hermeneutisk forskningsdesign, undersøkte vi i Artikkel 2 hvordan kreft-overlevere med bekken LRTI erfarte å gjennomgå HBOT. Data ble samlet inn via dybdeintervjuer med 20 deltakere. Intervjuene ble tatt opp på lydbånd, ordrett transkribert og analysert ved bruk av Systematisk Tekstkondensering. Fire hovedtemaer fra analysen synliggjorde informantenes erfaringer: 1) ‘Tilnærming til en ukjent verden’. Dette temaet belyste at tross informasjon i forkant av behandlingen, var informantene bekymret, men svært motiverte for HBOT, 2) ‘Fra å føle seg bekymret til å bli kjent’. Dette temaet utdypet HBOT som en prosess der en kombinasjon av relevant informasjon, klare rutiner, personsentrert omsorg var viktige faktorer for aksept og mestring av behandlingen, 3) ‘Et langvarig behandlingsforløp’. Dette temaet belyste at fraværet fra hjemmet og sosiale relasjoner var akseptable ettersom møte med medpasienter tillot et unikt fellesskap å utvikle seg, og 4) ‘Behandlingsforløpet gikk bedre enn forventet’. Dette temaet viste at de fleste deltakerne kun opplevde mindre, forbigående og svært tolerable bivirkninger av HBOT, hvorved majoriteten beskrev initial symptomlindring underveis i behandlingen.
Gjennom en kvantitativ tilnærming og et før – og etter forskningsdesign, studerte vi i Artikkel 3 utviklingen av, og assossiasjonene mellom, symptomer på bekken LRTI og HRQOL etter HBOT ved slutten av behandlingen (T2), og ved seks måneders oppfølging (T3). Nittifem deltakere (gjennomsnittsalder 65 år, 52.6 % menn) ble inkludert. Resultatene indikerte at bekken LRTI symptomer, HRQOL symptom skala, søvn, diare, smerte, fatigue, generell HRQOL og alle funksjonsskalaer var signifikant forbedret seks måneder etter behandling (P-område =0.00-0.04). Endringer var til stede allerede ved slutten av behandlingen og opprettholdt eller ytterligere forbedret ved 6 måneders oppfølging. Det ble kun funnet en svak, men signifikant korrelasjon mellom endringer i symptomer og overordnet HRQOL ble funnet (Pearson r-område 0.20-0.27).
I tillegg til resultatene fra de tre artiklene, bidrar sammenstillingen av de kvantitative og de kvalitative resultatene til en økt, omfattende og nyansert kunnskap og forståelse for deltakernes situasjon ved oppstart av behandlingen, behandlingsprosessen, deltakernes situasjon ved avslutning og seks-måneders oppfølging etter HBOT. De sammenslåtte resultatene fra før oppstart av HBOT indikerte stor symptombyrde, psykiske belastning, svekket HRQOL, som påvirket alle områder av livet. HBOT representerte en ukjent, men håpefull behandlingsmodalitet. De kvalitative funnene som beskriver selve behandlingsprosessen, viste at det var vanskelig for informantene å absorbere HBOT informasjonen. Deltakerne tilpasset seg imidlertid raskt til HBOT prosedyrene. Her var sykepleiernes oppfølging og omsorg avgjørende. Det langvarige HBOT forløpet, borte fra dagliglivet ble til en viss grad oppveid av støtte fra medpasienter. Ved behandlingsslutt viste de sammenslåtte resultatene forbedrede bekken LRTI symptomer, og de fleste HRQOL dimensjoner, samt at deltakerne erfarte minimale bivirkninger av HBOT. Ved seks måneders oppfølging indikerer de kvantitative resultatene ytterligere forbedrede LRTI symptomer og HRQOL.
Så vidt vi vet er dette den første mixed-metode studien som studerer hele prosessen med symptombyrde, og HRQOL hos kreft-overlevere med stråleskader i bekkenet som gjennomgår HBOT. Kunnskapen fra denne avhandlingen viser behov for økt kunnskap og utdanning av helsepersonell knyttet til stråleskader i bekkenområdet, betydningen av systematisk kartlegging av symptomer på stråleskader og HRQOL etter stråling i bekkenområdet, god symptomlindring og opplæring av kreftoverleverne i adekvat symptombehandling og mestring. Videre gir resultatene fra denne studien sterke føringer for at kreftoverlevere med stråleskader i bekkenområdet og redusert HRQOL kan ha stor nytte av HBOT. Spesielt kan redusert symptombyrde og forbedret HRQOL med økt rolle – og sosial funksjon ha stor betydning for disse kreftoverleverne hverdagsliv. Selv om resultatene fra denne studien ikke kan generaliseres, bidrar den til viktig kunnskap på et lite utforsket område og en viktig basis både for klinisk praksis og videre forskning.Curative radiotherapy for cancer may lead to severe late radiation tissue injuries (LRTI). However, limited knowledge exists about pelvic cancer survivors’ LRTI symptoms, distress and health-related quality of life (HRQOL). Hyperbaric oxygen therapy (HBOT) is an adjuvant therapy for LRTI, but has only been studied to a limited extent. The overall purpose of this thesis was therefore to provide an increased understanding of the symptom burden and HRQOL of cancer survivors undergoing HBOT for pelvic LRTI.
Patients enrolled in the study were recruited from cancer survivors with pelvic LRTI assigned to the Norwegian National Unit for Planned Hyperbaric Oxygen Treatment. Here, participants received HBOT in a mono-place pressure chamber, breathing pure oxygen at a pressure of 2.4 atmosphere absolute for 90 minutes once a day for six weeks.
A mixed-methods approach with an explanatory sequential research design was adopted, whereby data was collected sequentially through self-reported questionnaires at baseline (T1), on completion (T2) and six months after HBOT (T3), and in-depth interviews were performed on completion of HBOT.
Taking a quantitative approach with a descriptive cross-sectional research design, Paper 1 studied the symptom burden, distress and HRQOL in survivors with established pelvic LRTI compared to norm populations, and the relation between these factors at baseline. Here, 107 participants (mean age 64, 53% men) were included. Compared to norms, participants reported more urinary (mean 68.7 vs. 89.5; p=.00; d=1.4) and bowel symptoms (mean 62.5 vs. 92.4; p=.00; d=2.7), increased psychological distress (mean 13.4 vs. 10.3; p=.00; d=0.6), and overall poorer HRQOL (mean 54.9 vs. 71.2; p=.00; d=0.7). A higher symptom burden and higher levels of psychological distress were associated with lower HRQOL (r2=46%), but psychological distress did not moderate the influence of symptoms on HRQOL.
Taking a qualitative approach with a phenomenological-hermeneutical research design, Paper 2 explored how cancer survivors with pelvic LRTI experienced undergoing HBOT. Data was collected via in-depth interviews with 20 participants. The interviews were audiotaped, verbatim transcribed and analysed using Systematic Text Condensation. Four main themes emerged from the analyses to describe the participants’ experience of HBOT: 1) ‘Approaching an unknown world’. This theme illuminated that, despite information prior to the treatment, informants were worried about, but highly motivated for HBOT; 2) ‘From feeling worried to becoming familiar’. This theme elaborated on HBOT as a process whereby a combination of relevant information, clear routines and person-centred care were important acceptance and coping factors during HBOT; 3) ‘A long lasting treatment course’. This theme showed that absence from home and social relations were acceptable, since meeting peer patients allowed a unique community to develop; and 4) ‘The treatment course went better than expected’. This theme elaborated on how most participants only experienced minor, temporary and highly tolerable side-effects of HBOT, where most participants described initial symptom relief during the treatment course.
Taking a quantitative approach with a pre-test – post-test research design, Paper 3 studied the development of, and the associations between, symptoms of LRTI and HRQOL, with six-months follow-up after HBOT. Ninety-five participants (mean age 65 years, 52.6% men) were included. Pelvic LRTI, overall HRQOL, and all function scales and the HRQOL symptom scales of sleep, diarrhoea, pain and fatigue improved significantly six months after treatment (P-range =0.00-0.04). Changes were already present on the completion of HBOT and were maintained or further improved up to follow-up at T3. Only a weak significant correlation between changes in symptoms and overall HRQOL was found (Pearson r-range 0.20-0.27).
In addition to the results from the three papers, the merging of the quantitative and qualitative results provides increased, comprehensive and nuanced understanding and knowledge of the participants’ situation at baseline and in the HBOT process, and the participants’ situation on completion of HBOT and at six-month follow-up. Here, the merged findings at baseline show that all areas of the participants’ lives were highly impaired, documented as a severe LTRI symptom burden, psychological distress and impaired HRQOL, whereby HBOT was expressed as a hopeful treatment opportunity. The qualitative data describing the HBOT process indicates that it was difficult for the participants to absorb the HBOT information provided before treatment. However, the participants adjusted quickly to the HBOT procedures, whereby the nurses’ follow-up and care were crucial. The long-lasting HBOT course away from daily life was to a certain degree outweighed by peer support. On completion of HBOT, the merged results indicated an improved symptom burden and improved HRQOL, and limited side-effects. At six-month follow-up, the quantitative results showed a further improvement from the end of HBOT in pelvic LRTI, and overall HRQOL. However, the participants still had pelvic LRTI and impaired HRQOL at follow-up.
To the best of our knowledge this is the first mixed-methods study which studies the entire process of pelvic LRTI and HRQOL of cancer survivors with pelvic LRTI undergoing HBOT. The knowledge gained from this thesis illustrates the need for increased competence and education of healthcare professionals about pelvic LRTI, the importance of systematic assessment of pelvic LRTI symptoms and HRQOL after radiation, proper symptom management, and educating survivors in adequate symptom management and coping skills. Furthermore, the results provide strong evidence that cancer survivors with pelvic LRTI and impaired HRQOL may benefit from undergoing HBOT. In particular, reduced symptom severity and improved social and role function may influence daily living positively. Even if the results from this study cannot be generalised, the results do provide important knowledge in a field that has only been studied to a limited extent, and an important basis for clinical practice and further research. Doktorgradsavhandlin
Closing the Gap: Enhancing Technology Programming for Youth in North Minneapolis
No full textA technology divide persists in the United States. Recent studies have shown that young people of color, low-income individuals, and women are still underrepresented in science, technology, engineering, and math (STEM) careers and career training programs (NSF, 2003). Young people of color face several barriers for entry into STEM related careers including lack of role models and networking, information gap along with digital divide, perception of IT as a while male career, and lack of commitment from practice and the academy to recruit and work to retain young people of color in STEM related fields of study (Payton, 2004). Alternatives aims to respond to this gap and to assist young people of color to break down the barriers. This final report documents the findings, conclusions, and recommendations of an applied research project into STEM based programming. The report is organized into four main sections. The first presents an overview of the issue Alternatives aims to address, namely the technology gap among urban youth of color. The second major section provides an overall description of Alternatives, one of a very few youth programs focused on technology capacity building in North Minneapolis. The third section crafts a programmatic description based on scholarly and research evidence. The final section offers Alternatives conclusions and recommendations based on a comparison of its program to the research-based program. This applied research project aims to open up conversations on how Alternatives can provide the best program given available resources.Conducted on behalf of Alternatives Inc. Supported by the Northside Seed Grant program (NSG), a program of the Center for Urban and Regional Affairs (CURA), University of Minnesota.Dixon, Brice; VeLure Roholt, Ross; Alternatives Inc.. (2009). Closing the Gap: Enhancing Technology Programming for Youth in North Minneapolis. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/196312
Design, Verification and Testing of a Digital Signal Processor for Particle Detectors
No full textThe A Large Ion Collider Experiment (ALICE) at the Large Hadron Collider at CERN is upgrading two of its sub-detectors, the Time Projection Chamber and Muon Chambers, with new front-end electronics to handle the expected higher Pb–Pb collision-rates in the next running period (Run 3) foreseen to start in 2021. The higher collision rate requires the detectors to employ a continuous readout of the data from the front-end, in contrast to the previous triggered readout. The devices currently employed for the readout of the detectors can only operate in triggered mode and need to be replaced. A new 32-channel integrated circuit called SAMPA has been designed to match the requirements of both detectors. The SAMPA device contains a charge sensitive amplifier, a pulse shaper, and a 10-bit 10MHz analogue to digital converter for each channel and a common digital signal processor part. The digital signal processor provides various signal filtering and conditioning operations to improve on the data compression ability. Acquisition can be done in either triggered or continuous mode and the data is offloaded through 320 Mbps differential serial links, allowing a data throughput of up to 3.2 Gbps. The first prototype of the SAMPA was delivered in 2014, the second in 2016 and the third was delivered in end of 2017. The final production run was done in mid- 2018 and completed the testing at the end of 2018. Front-End Card production and testing is underway and the Muon Tracking Chamber (MCH) and Time Projection Chamber (TPC) are ready for installation in mid-2019. The main purpose of this thesis has been to specify, design, test and verify the digital signal processing part of the SAMPA device to encompass the needs of the detectors involved. Innovative solutions have been employed to reduce the bandwidth required by the detectors, as well as adaptations to ease data handling later in the processing chain. By means of simulations, test procedures, verification methods and applied methods for design of reliable systems, a major part of the work has been on qualifying the design for submission to production. Since the design submission process and the following production time of the device is quite long and as the only means of verifying and reading out data from the analogue front-end and the analogue to digital converter is through the digital part of the device, it is of the essence to have a complete functioning prototype of the digital design before submission. A high-speed data acquisition system was developed to enable test and verification of the produced devices. It has been used in all facets of qualification of the device for use by the detectors. Three rounds of prototypes have been produced and tested. Only minor modifications to the digital design were added between the second and third prototype. The final production of about 80 000 devices has been completed with the same design as for the third prototype. No major issues have been found in the final design. The design and test features implemented in the design have been utilized in the production testing and a final yield of close to 80% have been reached
Qualification of the ALICE SAMPA ASIC With a High-Speed Continuous DAQ System
No full textDuring the Long Shutdown 2 of CERN's Large Hadron Collider, foreseen to start in 2019, the ALICE experiment will upgrade its time projection chamber (TPC) detector to cope with a Pb-Pb collision rate of 50 kHz in the next running phase. In the upgraded TPC, the gas electron multiplier (GEM) technology and continuous readout will replace the existing multiwire proportional chambers and triggered readout system. The GEM signals will be processed using a new custom designed mixed-signal front-end chip named SAMPA. The first version of SAMPA was delivered in 2014, and the production of the final version is in progress. This paper gives an overview of the design of the data acquisition system used in testing of the analog behavior of the first SAMPA version and the performance results of a SAMPA coupled to a pulse generator and a GEM detector prototype
The Social Determinants of Native Youth Gang Involvement
No full textWhile youth gang involvement nationally is believed to be on the rise, few policies and services are in place to address this issue, leaving primary responsibility to law enforcement. The focus of such responses shift quickly to deterrence and suppression strategies, tactics aimed at reducing crimes committed by gangs. These strategies alone are typically unsuccessful. This article describes a community-based participatory research project investigating the presence and activities of youth gangs in one Native American tribal community in the Midwest. Findings regarding demographics, law enforcement, community perceptions, school and student perceptions, and community resources are presented. Analysis reveals evidence that gang involvement should be seen not only as a result of risk and protective factors in the lives of young people but also as a youth response to multiple, pervasive social factors, including poverty, historical trauma, and continuing racism—what we are beginning to name “social determinants” of youth gang activity. We include recommendations for youth and community response to social determinants.The research upon which this article is based was supported by a grant from CURA's Faculty Interactive Research Program. The program was created to encourage University faculty to conduct research with community organizations and collaborators on issues of public policy importance for the state and community. These grants are available to regular faculty at the University of Minnesota and are awarded annually on a competitive basis.University of Minnesota: Center for Urban and Regional Affairs; Roholt, Ross VeLure; Johnston-Goodstar, Katie; Eubanks, Don. (2016). The Social Determinants of Native Youth Gang Involvement. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/178981
“Et prosjekt er et prosjekt er et prosjekt”. En analyse av prosjektbegrepets utvikling og betydning i det norske språket, med hovedvekt på kulturpolitisk retorikk og scenekunstdiskurs
No full textIn this dissertation I examine how the concept of project has been used in the Norwegian language, in particular in the rhetoric of cultural policy and the discourse of stage arts. As a point of departure, I postulate that the prevalence of this concept has increased in recent decades, which the dissertation confirms. The dissertation examines when this breakthrough occurred and analyses what this discursive development may mean. After a general overview of the development of the concept in the vernacular, the dissertation focuses on the evolution of the concept in the rhetoric of cultural policy in Norway and in the discourse of stage arts. The theoretical framework for the dissertation is comprised of conceptual history and speech-act theory, as well as the theories of the Danish philosopher Anders Fogh Jensen concerning the notion of the project society (Prosjektsamfunnet). In general the dissertation demonstrates that project, as a concept, as experienced a positive turn since approximately 1960, which played a decisive role in its breakthrough. From being a somewhat negatively charged concept that provoked scepticism, it became a concept charged with positive expectations. These expectations are among other things triggered by the positivity of the semantic field surrounding the concept. Project theory has been a significant contributing factor to this development following the Second World War. Another contribution came through pedagogy, which early on invested positive and desirable values such as desire, dedication and motivation in the concept. This evolution is visible in all of the dissertation’s source material, first in newspaper sources, letters and opinion pieces, and later in cultural policy documents and debates in the field of stage arts. Somewhat contrary to other cultural policy research, the dissertation demonstrates that Norwegian cultural policy hasn’t undergone a project turn in the sense that project organisation and financing have become important cultural policy tools in recent decades. Despite the fact that in the rhetoric of cultural policy, projects are to a large extent declared positive and important priorities. Instead, the dissertation argues that the breakthrough of project as a concept in the rhetoric of cultural policy should be understood in the context of the ideological difference between a conservative and a social-democratic view of the value of culture. Focusing on projects emphasises activity rather than quality. Cultural policy has consequently given less attention to important issues of infrastructure and predictability. The dissertation argues further that the use of project as a concept in the rhetoric of cultural policy has established a dichotomy between «project» and «institution». In addition to being a linguistic distinction, this dichotomy is rooted in public management and has become fundamental for understanding the cultural field in Norway. The dissertation argues that the project concept has been a constitutive force in the field of stage arts in Norway over the last 25 years. Two debates are analysed in particular. The first debate regards the development of project theatre as a concept in the early 1990s, and how it was used to highlight a marginalised milieu and an aesthetic alternative within the artistic landscape. The second debate regards the restructuring of Arts Council Norway’s grant scheme for independent stage arts in 1998, when operating grants where replaced by project grants. The dissertation demonstrates that these debates have had significant consequences in and for the field of stage arts in Norway. The use of project as a concept has played a role in determining which arguments were heard, thus influencing the development of the field
«På mørkets skjøre, blanke overflatehinne» - An investigation into the relationship between pathos and existential themes in the writings of Tor Ulven
No full textI denne masteroppgaven kartlegger jeg hvordan patos viser seg i Tor Ulvens forfatterskap, med hensikt å undersøke hvordan tekstens følelsesinnhold står i forhold til Ulvens grunnleggende pessimistisk-eksistensielle tematikk. Formålet med dette er å fremheve hvordan angsten viser seg i Ulvens diktning, og hvordan det også oppstår øyeblikk hvor angsten er fraværende og tekstens patos formidler kjærlighet, medlidenhet eller en form for optimisme. I oppgaven gjør jeg en rekke lesninger av Ulven-tekster fra hele forfatterskapet, og undersøker i hvilken grad patos er fremtredende, og hvordan en utforskning av Ulvens patos kan utvide vår forståelse for forfatterskapet i sin helhet. Det har i tidligere Ulven-tolkning blitt lagt stor vekt på konsekvensene av Ulvens eksistensielle tematikk, og det har også til en viss grad blitt skrevet om patos i Ulvens diktning, men jeg mener disse temaene i for liten grad har blitt satt i sammenheng. Det er dette jeg ønsker å gjøre i denne oppgaven, men hensikt å introdusere alternative måter å lese Ulven på. Mens Ulvens forfatterskap på ingen måte kan karakteriseres som oppløftende og optimistiske, inneholder det likevel flere kilder til varme og medmenneskelighet enn den pessimistisk-eksistensielle tematikken kanskje indikerer.Tor Ulven (1953-1995) was a Norwegian writer. He debuted in 1977 with the poetry collection Skyggen av urfuglen, and published a number of poetry collections, short story collections, as well as the novel Avløsning (Replacement; the only one of Ulven’s books that has been published in English translation), until his death in 1995. Ulven’s writings are known for conveying a pessimistic existential outlook, written in a cold and seemingly unaffected language. However, there are places in Ulven’s writings where this coldness breaks and the text convey a strong pathos. In this master thesis I will be looking at how pathos manifests itself within the writings of Tor Ulven, with the intention of examining the relationship between the emotional substance and the dominating pessimistic-existential themes in his writings. By doing this, I intend to highlight how anxiety presents itself in the texts, and how there can also emerge moments in the writings where the anxiety is absent, and the text’s pathos conveys love, compassion or even, to a certain extent, optimism. In the thesis I will do interpretations of a number of Ulven’s texts from a number of his literary works, and investigate to which extent pathos is present, and discuss how such an investigation can broaden our understanding of Ulven’s works as a whole. Previous interpretations have extensively discussed the consequence of Ulven’s existential themes, and to a certain extent the pathos of the texts has also been discussed, but I believe that the connection between these two topics has yet to be sufficiently explored. This is what I intend to do in this thesis, with the ambition of introducing alternative ways of reading Ulven. While Ulven’s writings by no means can be classified as cheerful or optimistic, there’s still more to his works than the existential-pessimistic themes might indicate.Allmenn litteraturvitenskap mastergradsoppgaveALLV350MAHF-LIT
Design, implementation and testing of SRAM based neutron detectors
No full textNeutrons of thermal and high energies can change the value of a bit stored in a Static Random Access Memory (SRAM) memory chip. The effect is non destructive and linearly dependent on the amount of incoming particles, which makes it exploitable for use as a neutron detector. Detection is done by writing a known pattern to the memory and continuously reading it back checking for wrong values. As the SRAM memory is immune to gamma radiation it is ideal for use in for instance medical linear accelerators for detection of neutron dose to a patient. The intention of this work has been twofold: (1) Testing of different SRAM devices of different bit-sizes, manufacturers, feature sizes and voltages for their sensitivity to neutrons of different energies from thermal to high energies. (2) Design and implement detector hardware, firmware and its accompanying readout system for successful use in irradiation testing. The work has been done in close collaboration with Eivind Larsen, whose main contributions has been related to the nuclear physics aspect of the work in addition to arrangements in regard to beam setup and experimentation. Testing have been done at the Physikalisch-Technische Bundesanstalt (PTB) facility in Braunschweig Germany in a quasi-monochromatic neutron beam of 5:8MeV, 8:5MeV and 14:8MeV, finding a dependence of the sensitivity on the energy. In addition there have been testing conducted in the high energy hadron field at CERF at CERN, finding that by using the results from the other experiments an estimated range of the saturation cross section could be determined. Testing was also conducted at two occasions in the 29MeV proton beam at Oslo Cyclotron Laboratory (OCL) in Oslo Norway, where it was found that the detector could be used as a reference detector for beam monitoring and for beam profile characterization. The cross sections of the detectors were found to be comparable to the 14:8MeV cross section found at PTB. Thermal neutron testing of the devices was done in the thermal neutron field of the nuclear reactor at Institute for Energy Technology (IFE) at Kjeller Norway. All the devices were found to be sensitive to the field. Detector electronics, adapted to the different devices, has been built which can withstand the same radiation as the memory device without malfunctioning. There has been a focus on using Commercial Off The Shelf (COTS) components for reducing the total cost of the detector to about 100-200$US. The use of COTS SRAM memory devices also simplifies the reproducibility and availability of spares. The detector currently uses a two way communication between the detector and iv Abstract the readout computer over two pair of cables reducing the amount of cabling needed for experiments. The detectors can be connected to the communication link in a bus fashion, currently enabling a total of 14 detectors to be tested simultaneously from 100m away, over the same cable. Single Event Latch-up (SEL) and problems with irregular count rate of SRAMs created in the 90nm fabrication node has created problems during testing. Some solutions and techniques to mitigate these in hardware and firmware are presented in this work.Master i FysikkMAMN-PHYSPHYS39
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