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Sandheds veje : lutherske strejflys over Ólafur Jónsson á Söndums : digtning
Get PDFThe goal of the current study is to throw light on a rather neglected part of
Icelandic literary and cultural history: Imagery in early Icelandic hymn poetry.
More specifically, it is an investigation into the poet Ólafur Jónsson á Söndum’s
(c1560–1627) use of imagery. Martin Luther’s thoughts on language and
use of linguistic figures or imagery (chapter 4) are taken as a starting point for
the analysis. With this historical point of departure the aim is twofold: firstly
to provide an account of the theology of Ólafur Jónsson as seen through the
imagery. Secondly, to gain knowledge of how the imagery contributes to the
effect of the poems.
Chapters 2 and 3 serve as an introduction to the main study by adressing the
cultural and historical context of the authorship of Ólafur Jónsson, leading
the reader to the main subject of the dissertation. These two chapters contain
a thorough description of the historical settings of the authorship with
special emphasis on the cultural and educational structures in play. The poet
himself is presented to the reader with a short biography. An overview over
the transmission of his work is given, along with a short outline of the poetry
as it appears in the material.
This is followed by a theological examination of imagery in chapter 5. The examination
is limited to the imagery from four specific, but theologically very
central topics: the anthropology, the idea of God, the understanding of salvation
and the powers of evil. The imagery excerpted from the corpus of song
texts is discussed in detail based on relevant parts of the theology of Martin
Luther as found in his most central writing.
In chapter 6, the material is examined in three different ways, showing the
imagery in interaction with the reader. In the first section, three verses from
an exegetic song on Luke vii. 36–50 are discussed in some detail. The following
section presents an analysis of Ólafur’s use of images from the realm of nature.
The chapter concludes with an analysis of the imagery of a whole song text.
The dissertation also contains text and translation into Danish of two central
song texts, Sjálfur Guð, drottinn sannleikans and Sterkur himnanna stýrir, as
well as a textual edition of the biography of Ólafur Jónsson by the reverend
Magnús Snæbjarnarson.Helsta markmið þessa rannsóknarverkefnis er að varpa ljósi á lítt kannað svið
íslenskrar bókmennta- og menningarsögu: myndmál í elsta sálmakveðskap
á íslensku, nánar tiltekið notkun myndmáls í kveðskap vestfirska skáldsins
sr. Ólafs Jónssonar á Söndum (um 1560–1627). Rannsóknin tekur formlega
mið af (4. kafli) hugmyndum Marteins Lúthers um tungumálið og myndrænt
tungutak. Á þeim sögulega grunni er tilgangurinn fyrst og fremst (A)
að varpa ljósi á hvernig skáldið tjáir guðfræði sína með myndrænu orðalagi
og ennfremur (B) að kanna hvernig myndmálið á þátt í að auka áhrifamátt
skáldskaparins.
Til að leggja grunn að rannsókninnni er í 2. og 3. kafla gerð grein fyrir hinu
menningarlega og sögulega samhengi sem leiðir lesandann að efninu sem tekið
er fyrir í köflunum sem á eftir fara. Lýst er þeirri menntun sem Ólafur Jónsson
hlaut og þeim menningarlega bakgrunni sem hann lifði og hrærðist í. Æviferill
hans er rakinn og gefið er yfirlit yfir varðveislu verka hans í handritum og loks
fjallað almennt um það sem helst einkennir þann kveðskap sem tekinn er fyrir
í ritgerðinni.
Til að svara fyrri spurningunni (A) sem rædd er í 5. kafla er efnið takmarkað við
nokkur guðfræðileg meginatriði: mannskilninginn, guðshugtakið, hjálpræðiskenninguna,
og loks hin illu öfl. Þessi atriði eru tekin til athugunar lið fyrir lið
út frá samsvarandi þáttum í guðfræði Lúthers eins og hún birtist í nokkrum
helstu ritum hans.
Seinni spurningunni (B) er reynt að svara í 6. kafla með því að nálgast efnið á
annan hátt í þeim tilgangi að sýna hvernig myndmálið virkar á viðtakandann.
Þannig er í fyrsta lagi fjallað um hvernig Ólafur Jónsson notar þrjú mjög myndræn
erindi til að leggja áherslu á meginatriði í einum sálmi, því næst er fjallað
um hvernig náttúran er notuð á myndrænan hátt í þeim sálmum sem hér eru
teknir fyrir. Og að lokum er gerð nákvæm grein fyrir notkun myndmáls í einum
ákveðnum sálmi.
Ritgerðinni fylgir að auki texti og þýðing á tveimur sálmum eftir Ólaf Jónsson,
Sjálfur Guð, drottinn sannleikans og Sterkur himnanna stýrir; svo og kaflar úr
æviágripi skáldsins eftir sr. Magnús Snæbjarnarson.Rannsóknasjóður Háskóla Íslands, Union Evangelischer Kirchen (under Evangelische Kirche in Deutschland)
Effects of interlayer exchange on collapse mechanisms and stability of magnetic skyrmions
Get PDFPost-print / Lokaútgáfa höfundarTheoretical calculations of thermally activated decay of skyrmions in systems comprising several magnetic monolayers are presented, with a special focus on bilayer systems. Mechanisms of skyrmion collapse are identified and corresponding energy barriers and thermal collapse rates are evaluated as functions of the interlayer exchange coupling and mutual stacking of the monolayers using transition state theory and an atomistic spin Hamiltonian. In order to contrast the results to monolayer systems, the magnetic interactions within each layer are chosen so as to mimic the well-established Pd/Fe/Ir(111) system. Even bilayer systems demonstrate a rich diversity of skyrmion collapse mechanisms that sometimes coexist. For very weakly coupled layers, the skyrmions in each layer decay successively via radially symmetric shrinking. Slightly larger coupling leads to an asymmetric chimera collapse stabilized by the interlayer exchange. When the interlayer exchange coupling reaches a certain critical value, the skyrmions collapse simultaneously. Interestingly, the overall energy barrier for the skyrmion collapse does not always converge to a multiple of that for a monolayer system in the strongly coupled regime. For a certain stacking of the magnetic layers, the energy barrier as a function of the interlayer exchange coupling features a maximum and then decreases with the coupling strength in the strong coupling regime. Calculated mechanisms of skyrmion collapse are used to ultimately predict the skyrmion lifetime. Our results reveal a comprehensive picture of the thermal stability of skyrmions in magnetic multilayers and provide a perspective for realizing skyrmions with controlled properties.We gratefully acknowledge financial support from the
Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) via project no. 414321830 (HE3292/11-1) and no. 418425860 (HE3292/13-1), the Icelandic Research Fund (Grant No. 217750 and 184949), the University of Iceland Research Fund and the Russian Science Foundation (Grant No.19-72-10138).Peer Reviewe
Conceptual System Dynamics and Agent-Based Modelling Simulation of Interorganisational Fairness in Food Value Chains: Research Agenda and Case Studies
Get PDFSystem dynamics and agent-based simulation modelling approaches have a potential as tools to evaluate the impact of policy related decision making in food value chains. The context is that a food value chain involves flows of multiple products, financial flows and decision making among the food value chain players. Each decision may be viewed from the level of independent actors, each with their own motivations and agenda, but responding to externalities and to the behaviours of other actors. The focus is to show how simulation modelling can be applied to problems such as fairness and power asymmetries in European food value chains by evaluating the outcome of interventions in terms of relevant operational indicators of interorganisational fairness (e.g., profit distribution, market power, bargaining power). The main concepts of system dynamics and agent-based modelling are introduced and the applicability of a hybrid of these methods to food value chains is justified. This approach is outlined as a research agenda, and it is demonstrated how cognitive maps can help in the initial conceptual model building when implemented for specific food value chains studied in the EU Horizon 2020 VALUMICS project. The French wheat to bread chain has many characteristics of food value chains in general and is applied as an example to formulate a model that can be extended to capture the functioning of European FVCs. This work is to be further progressed in a subsequent stream of research for the other food value chain case studies with different governance modes and market organisation, in particular, farmed salmon to fillet, dairy cows to milk and raw tomato to processed tomato.Peer Reviewe
Price relationships along the Norwegian salmon value chains: A comparative study of the leading consumption market in France and the largest processing industry in Poland
Get PDFThis study investigates price relationships along the Norwegian salmon value chains in France, the EU’s leading consumption market for salmon, and Poland, the EU’s largest
“processing hub.” Using a vector error correction model framework, our results indicate that the salmon price determination is a supplier-driven process, with the export prices in Norway influencing prices in France and Poland, but not vice versa.
Results also suggest that price linkages are strong between the export market in Norway and the retail market in France and the processing industry in Poland; however, the Polish
retail sector is separated from markets at the upstream level, while price discovery at the French wholesale market is dominated by the retail market. Our findings imply that the evolved market structures lead to efficiently functioning retail markets in France and wholesale markets in Poland, but put the French wholesale and Polish retail markets at a disadvantage.The research on which this paper is based formed part of the VALUMICS project
“Understanding Food Value Chain and Network Dynamics” funded from the European
Union’s Horizon 2020 research and innovation programme.Peer Reviewe
Syntactic approaches to negative results in process algebras and modal logics
Get PDFConcurrency as a phenomenon is observed in most of the current computer science
trends. However the inherent complexity of analyzing the behavior of such a system
is incremented due to the many different models of concurrency, the variety of applications and architectures, as well as the wide spectrum of specification languages and demanded correctness criteria. For the scope of this thesis we focus on state based models of concurrent computation, and on modal logics as specification languages. First we study syntactically the process algebras that describe several different concurrent behaviors, by analyzing their equational theories. Here, we use well-established techniques from the equational logic of processes to older and newer setups, and then transition to the use of more general and novel methods for the syntactical analysis of models of concurrent programs and specification languages. Our main contributions are several positive and negative axiomatizability results over various process algebraic languages and equivalences, along with some complexity results over the satisfiability of multi-agent modal logic with recursion, as a specification language.Samhliða sem fyrirbæri sést í flestum núverandi tölvunarfræði stefnur. Hins vegar er eðlislægt flókið að greina hegðun slíks kerfis- tem er aukið vegna margra mismunandi gerða samhliða, fjölbreytileikans af forritum og arkitektúr, svo og breitt svið forskrifta mælikvarða og kröfðust réttmætisviðmiða. Fyrir umfang þessarar ritgerðar leggjum við áherslu á ástandsbundin líkön af samhliða útreikningum og á formlegum rökfræði sem forskrift tungumálum. Fyrst skoðum við setningafræðilega ferlialgebrurnar sem lýsa nokkrum mismunandi samhliða hegðun, með því að greina jöfnukenningar þeirra. Hér notum við rótgróin tækni mynda jöfnunarrökfræði ferla til eldri og nýrri uppsetningar, og síðan umskipti yfir í notkun almennari og nýrra aðferða fyrir setningafræðileg greining á líkönum samhliða forrita og forskriftartungumála. Helstu framlög okkar eru nokkrar jákvæðar og neikvæðar niðurstöður um axiomatizability yfir ýmis ferli algebrumál og jafngildi, ásamt nokkrum samSveigjanleiki leiðir af því að fullnægjanleiki fjölþátta formrökfræði með endurkomu, sem a forskrift tungumál.RANNIS: `Open Problems in the Equational Logic of Processes’ (OPEL) (grant No 196050-051)
Reykjavik University research fund: `Runtime and Equational Verification of Concurrent Programs' (ReVoCoP) (grant No 222021
Erfðafræði þroskaraskana, ósjálfráðrar hreyfingar, hvatvísi og þráhyggju
No full textNeurodevelopmental disorders on the impulsivity-compulsivity spectrum are
chronic disabling conditions with an early onset. High rates of comorbidity have
been reported between Tourette syndrome (TS), Tics disorder (Tics), obsessive compulsive disorder (OCD), attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) and these disorders share cross-disorder risk,
conferred by common variants.
In this thesis the focus is on the genetics of human intracranial volume (ICV) and
five impulsivity-compulsivity spectrum neurological disorders (Tourette, Tics,
OCD, ADHD, and restless legs syndrome (RLS)) with the aim of finding novel
sequence variants conferring risk of these behaviours and study their cross disorder risk. The genetics of these disorders is complex. Despite large meta analyses, relatively few sequence variants have been associated with these disorders and perturbed biochemical pathways have not been clearly outlined.
Better understanding of their genetic underpinnings may greatly improve and
accelerate diagnosis, give insights into disease processes, and point to novel
targets for drug therapies.
Copy number variations (CNVs) introduce insertion/deletion throughout the
genome thereby impacting gene expression through gene dosage effect. A
candidate gene study confirms AADAC deletion as a risk factor for TS.
Moreover, a group of rare, recurrent CNVs, so called neuropsychiatric CNVs,
confer high risk of ADHD. This association highlighted shared genetic risk of
ADHD with ASD and schizophrenia. The GWAS meta-analysis of TS didn’t find
any significant association while aggregate risk score of common variants
confirmed polygenic nature of TS.
Through large meta-analyses, more sequence variants conferring risk of diseases
of the impulsivity-compulsivity spectrum have been uncovered. Colocalization
analyses were used to identify affected genes and Mendelian randomization to
search for causal relationships, with a focus on the biological insights these
associations are beginning to produce.
Variations in ICV can impact brain structure-function relationships. The GWAS
meta-analysis of ICV uncovered 64 sequence variants explaining 5.0% of the
trait’s variance. Genetic correlation analysis shows positive correlation between
ICV and cognitive abilities and neurological traits.
Phenome-wide genetic correlation (GC) and causal analyses were used to dissect
complex polygenic nature of TS, Tics, ADHD, OCD, and RLS. GC of these five
disorders with 1,140 published GWAS studies identified 59 common genetically
correlated traits (FDR < 0.05). The hierarchical clustering of 59 correlated traits
identified five latent clusters: (1) neuropsychiatric or neurotic disorders, (2)
emotional disorders, (3) peripheral and muscular pain (4) obesity / poor
lifestyle, and (5) cognition / learning traits.
Rare and common variants associate with TS, ADHD, RLS, and ICV. The key
question is whether variants, associated with structural changes in the brain,
cause neurological disorders through their effect on brain structure or
alternatively whether genetic predisposition to certain neurological disorders
impacts brain structure or development. Bidirectional MR analyses of 34
correlated disorders compared with ICV revealed that ICV either has a causal
effect on a neurodevelopmental disorder (ADHD) as well as on a neurodegenerative disorder (Parkinson’s) or these causal relationships may be driven by traits closely correlated with ICV.Taugaþroskaraskanir á hvatvísis-þráhyggju rófinu eru þrálát og hamlandi einkenni
sem koma oft fram snemma á lífsleiðinni. Há tíðni fylgiraskana finnast samhliða
Tourette heilkenni (TS), kækjum (Tics), þráhyggju- og áráttu- hegðun (OCD),
athyglisbrest með og án ofvirkni röskun (ADHD), og einhverfurófsröskun (ASD)
og dæmi eru um að sömu algengu breytileikarnir auka áhættu á mismunandi
röskunum. Þessi ritgerð fjallar um erfðafræði rúmmáls heila og fimm taugaþroskaraskana á hvatvísis-þráhyggju rófinu (Tourette, Tics, OCD, ADHD, og fótaóeirð (RLS)) með
það að markmiði að finna nýja breytileika sem ávísa áhættu af því að þróa þessar
svipgerðir og að rannsaka áhættu á krossröskun. Erfðafræði þessara raskana er
flókin. Þrátt fyrir stórar safngreiningar (meta-analysis), hafa tiltölulega fáir
breytileikar fundist sem ávísa áhættu á þessum röskunum, né varpað ljósi á þá
líffræðilegu ferla sem þar liggja að baki. Betri skilningur á erfðafræðilegri
undirstöðu þessara raskana gæti stórbætt og flýtt fyrir greiningu, gefið betri
innsýn inn í sjúkdómsferlið og bent á nýjar lyfjameðferðir. Eintakabreytileikar annaðhvort koma fyrir innskotum eða eyða út svæðum í erfðamenginu og hafa þannig áhrif á hversu mikið er tjáð af genum sem eru á þeirra áhrifasvæði. Leit í líklegum genum staðfestir að úrfelling á AADAC geninu er áhættu þáttur fyrir Tourette heilkenni. Þar að auki, höfum við sýnt fram á tengls á milli ákveðinna eintakabreytileika, sem hafa áður verið tengdir við
einhverfu og geðklofa, og ADHD. Þessi fylgni varpar ljósi á þá erfðafræðilegu
áhættu sem ADHD deilir með einhverfu og geðklofa. Safngreining niðurstaðna
úr víðtækri erfðamengisleit skilaði engum erfðabreytileikum sem voru í marktægt
hærri tíðni í TS en í viðmiðunarhópi. Þó staðfestir samanlagt arfgerðar-skor
fjölgena eðli Tourette heilkennis. Stórar safngreiningar hafa auðkennt nýja breytileika sem ávísa áhættu á röskun á hvatvísis-þráhyggju rófinu. Staðsetning breytileika og aðrar aðferðir hafa verið notaðar til að tengja breytileika við gen og Mendelsku slembivali beitt til að rýna í orsakasamhengi, með fókus á líffræðilega ferla þessi gen taka þátt í.
Breytileiki í rúmmáli heilans getur haft áhrif á tengsl á milli uppbyggingu og
virkni í heilanum. Stór safngreining niðurstaðna úr víðtækri erfðamengisleit á
rúmmáli heilans hefur leitt í ljós 64 breytileika í erfðamenginu sem útskýra um
iv 5.0% dreifni svipgerðarinnar. Erfðafylgnigreining (GC) sýnir jákvæða fylgni á
milli rúmmáls heilans og vitrænna hæfileika og taugasjúkdóma.
Breið svipgerða erfðafylgni greining og orsakagreiningar voru notaðar til að
kryfja flókin fjölgena sambönd á milli TS, kækja, ADHD, OCD og RLS. GC
þessara fimm raskana á móti 1,140 birtra niðurstaðana úr heilgenóms
erfðatengslaleitum, bar kennsl á 59 algeng svipbrigði sem eru sýna marktæka
erfðafylgni (FDR < 0.05). Stigveldis þyrpingagreining á þessu 59 svipgerðum
leiddi í ljós fimm dulda klasa; (1) taugaþroska- og geðraskanir, (2) tilfinningar
raskanir, (3) útlima og vöðva verkir, (4) offita / óheilbrigður lífstíll, (5) vitsmuna /
lærdóms svipgerðir. Sjaldgæfir og algengir breytielikar hafa verið tengdir við TS, ADHD, RLS og rúmmál heilans. Lykil spurning er hvort breytileikarnir, sem hafa verið tengdir við
breytingar í heila, valdi taugasjókdómum í gegnum áhrifin sem þeir hafa á
heilann, eða hvort erfðafræðileg tilhneiging til að þróa taugasjókdóma hefur
áhrif á uppbyggingu og þroska heilans. Tvíátta Mendelsk slmbivals greining á 34
svipgerðum, með innbyrgðis fylgni, samanborið við rúmmál heilans gaf til kynna
að rúmmál heilans annað hvort hefur áhrif á taugaþroska raskanir (ADHD) og
taugasjókdóma (Parkinson’s) eða þá að orsakasamhengið sé stýrt af svipgerðum
sem sýna sterka fylgni við rúmmál heilans.Gran support from the Marie Curie Initial Training Networks TS-EUROTRAIN (FP7-PEOPLE [Grant No. GA 316978]), and deCODE Genetics/Amgen, Iceland
Variable Stiffness Prosthetic Foot
Get PDFProsthetic devices are intended to replace missing limbs. Although this statement is simple, the design, testing, and validation of these devices are considerably complex. A number of energy-storing-and-returning prosthetic feet are commercially available, and the recently developed bionic prosthesis aims to increase ankle push-off power or ankle joint compliance. The motivation for this thesis is to propose an alternative device design for a variable sagittal stiffness prosthetic foot. The device must retain the benefits of existing energy-storing-and-returning devices with the addition of stiffness modulation possibilities but with limited additional mass. The second objective of this thesis is to propose an advanced machine testing procedure capturing data that are usually collected during user trials in a gait lab. The data collection can reduce the necessity for user testing in the early phases of the design process.
Four different concepts in which stiffness modulation is mechanically tested are explored in this work. Non-Newtonian foam was used in the first prototype device; however, the concept was abandoned due to the intrinsic limitations in the stiffness change of the material relative to impact and speed. A discrete stiffness mechanism was then modeled, allowing a considerable change in the foot response with a quick user action. Finally, a cantilever beam with a movable support was preferred, leading to the design of two different devices. A final prosthetic foot design that enables wireless sagittal ankle stiffness modulation by the user or prosthetist is proposed. The variable stiffness ankle foot prosthesis was evaluated mechanically and on transtibial amputees. The device was subjected to advanced machine testing to contrast the results with those of biomechanical testing. The developed input curves for simulated incline and decline walking on the machine are promising. The machine and biomechanical ankle test results were compared.
This work is anticipated to encourage the development of devices prioritizing simple yet clinically relevant functions as well as support biomechanical and mechanical engineers with a test method that can further advance the communication between these two engineering fields.Gervifótum er ætlað að koma í stað útlima sem vantar. Þrátt fyrir að þessi fullyrðing sé einföld þá er hönnun, prófun og staðfesting á réttri virkni fótanna flókin. Nokkrar tegundir gervifóta sem geyma og skila orku eru á markaði. Nýlega hafa komið fram gervifætur stýrðir af lífmerki og miða að því að auka kraft frá ökkla. Markmið þessa verkefnis var að hanna nýjan gervifót með breytilegri stífni. Fóturinn varð að hafa eiginleika núverandi fóta sem geyma og skila orku, ásamt möguleikum á breytilegri stífni án þess að auka massa fótarins umtalsvert. Annað markmið þessa verkefnis var að leggja til vélræna prófunaraðferð sem fangar gögn, sem venjulega er safnað við göngugreiningu notenda á rannsóknarstofu. Vélræn prófun getur dregið úr þörf á notendaprófum á fyrstu stigum hönnunarferlisins.
Í þessu verkefni voru fjórar útfærslur stífnibreytinga prófaðar vélrænt. Svampur með ólínulega stífni var notaður í fyrstu útfærslu. Fallið var frá henni vegna eðlislægra takmarkana á stífleika efnisins við högg og hratt álag. Næst var hönnun þar sem notandi gat breytt stífni ökklans umtalsvert á fljótlegan hátt, prófuð í tölvu. Þá var valin hönnun sem byggði á bita með hreyfanlegum undirstöðum sem leiddi til tveggja mismunandi útfærslna á ökkla. Lokahönnunin er gervifótur sem býður upp á þráðlausa stillingu stífleika ökkla. Gervifóturinn var prófaður og metinn vélrænt og á notendum í göngugreiningu sem höfðu misst fót fyrir neðan hné. Niðurstöðurnar fyrir göngu upp og niður brekku voru bornar saman og reyndust sambærilegar.
Gera má ráð fyrir að þetta verkefni hvetji til þróunar tækja sem forgangsraða mikilvægum eiginleikum fóta ásamt því að koma fram með prófunaraðferð sem aðstoðar verkfræðinga og hönnuði stoðtækja við frekari þróun og prófanir.This research was partly funded by Technology Development Fund grant number 164061-0611 and Icelandic Student Innovation Fund.
Össur was supporting manufacturing of prototypes
"Ég, sem þreyttur kem frá liðnum vetri": Um margbrotna stöðu skáldsins og þýðandans Jóns Óskars í íslensku menningarumhverfi
Get PDFÍ þessari ritgerð er könnuð staða skáldsins og þýðandans Jóns Óskars á íslenskum menningarvettvangi. Höfundarverki Jóns er fylgt eftir frá því hann fer að láta að sér kveða opinberlega á fimmta áratug síðustu aldar og nánast allt þar til hann lést 20. október 1998.
Árin sem Jón Óskar var virkur í bókmenntalífinu voru mikil umbrotaár bæði alþjóðlega og ekki síður hér heima á Íslandi. Þannig stendur síðari heimsstyrjöldin enn þegar Jón lætur á sér bæra sem skáld og hann er rétt um tuttugu og þriggja ára þegar lýðveldið er stofnað á Þingvöllum. Hann er á hátindi sem rithöfundur á því skeiði þegar byggist upp spenna milli Sovétríkjanna og Bandaríkjanna og fer ekki varhluta af andrúmslofti kaldastríðs eins og það birtist okkur hér uppi á Íslandi. Hann er af þeirri kynslóð sem var nánast skyldug til að taka afstöðu með eða á móti herliði á íslenskri grund í kjölfar Keflavíkursamningsins, Jón Óskar sér ´68 kynslóðina vaxa úr grasi og svo bregðast sjálfri sér og samferðafólki. Hann fylgist með uppgangi rokktónlistarinnar sem hann gefur lítið fyrir, hann horfir á erlendar sjónvarpsstöðvar sýna beint frá Persaflóastríðinu 1991. Hann lifir ekki aðeins tímana tvenna, hann lifir ótrúlega byltinga- og breytingatíma.
Inn í þetta samfélag yrkir Jón, mestmegnis óhefðbundin ljóð, módernísk – enda eitt af hinum svokölluðu „atómskáldum“. En hann þýðir líka erlenda ljóðlist og færir inn í íslenskt bókmenntakerfi, hann snarar ljóðlist úr öðrum tíma og stillir upp með þeirri formbyltingu sem fór fram í íslenskri ljóðagerð um og upp úr miðri tuttugustu öld. Þannig kemur Jón sér fyrir sem einskonar hliðvörður sem hleypir inn t.d. frönsku symbólistunum og mörgum öðrum skáldum frönskum og ítölskum sem höfðu gert garðinn frægan í Evrópu áratugum fyrr. Seinkoma (e. lateness) þessara erlendu skálda í gegnum hlið Jóns Óskars, þýðingar hans, inn í íslenskar bókmenntir eru í raun líkt og örmynd af nánast öllu höfundarverki Jóns – og líka veru hans, því allur hans ferill markast af seinkomu eða hiki. Þannig er stíll hans og erindi, en þó alls ekki undir neikvæðum merkjum, heldur sýnir ritgerðin fram á að Jón Óskar er það sem kallað er arrière-garde höfundur, eða bakfylkingarhöfundur, en orðin arrière-garde og bakfylking eru notuð jöfnum höndum í ritgerðinni.
Ritgerðin skiptist í fjóra meginkafla þar sem hugtök á borð við seinkoma, hik, arrière-garde eru leiðarstef, auk hugtaka á borð við tímabrengl, töf og frestun – og reyndar annarra af svipuðum meiði, en allt eru þetta hugtök sem með einum eða öðrum hætti fást við tímann og glímu manns og skálds við hann.
Rannsóknarspurningin er fjórþætt:
1) Hver er staða Jóns Óskars á íslenskum menningarvettvangi?
2) Hvernig birtist hann sem arrière-garde höfundur?
3) Hver eru helstu stíleinkenni Jóns og hver er fagurfræði hans, eða skáldskaparfræði?
4) Hvert sækir hann aðferð og fagurfræði og hvernig þróast þessir þættir á höfundarferlinum?
Í fyrsta kafla ritgerðarinnar er Jón Óskar kynntur og gerð grein fyrir þeirri aðferðarfræði sem er viðhöfð í ritgerðinni, þar kemur fram að rannsóknin er fyrsta viðamikla tilraunin til þess að varpa ljósi á Jón Óskar sem skáld og þýðanda, fyrsta tilraunin til þess að skoða hlutverk hans og stöðu og loks fyrsta tilraunin til þess að rýna í margt af því sem er undirliggjandi í fjölbreyttu höfundarverki hans. Skáldskapur Jóns, þýðingar hans og æviminningaskrif eru til umfjöllunar í kaflanum og eru, eins og í öðrum köflum ritgerðarinnar, grunnurinn að öllu því sem hér er til skoðunar.
Í öðrum kafla er hugtakið arrière-garde kynnt eins nákvæmlega og kostur er enda er hér verið að beita því í fyrsta sinn í rannsókn á íslenskri bókmennta- og menningarsögu, en með hugtakinu er greind skáldskaparfræði Jóns Óskars og hið fagurfræðilega inntak í erindi hans á íslenskum menningarvettvangi, rætur þeirrar fagurfræði og eðli hennar. Tíminn er fyrirferðamikið hugtak í þessum kafla ritgerðarinnar og leiðir það í margvíslegar áttir, svo sem að heimsslitafræðum, dulhyggju og aftur í franskan klassíkisma, svo eitthvað sé nefnt. Þá er gerð ítarleg grein fyrir því í þessum hluta hvernig T.S. Eliot hefur áhrif á Jón og hvernig sjá má í skáldskap Jóns Óskars þætti sem rekja má beint – en þó um Eliot – til enska skáldsins og heimspekingsins T.E. Hulme. Mikilvægi Henris Bergson er undirstrikað og sýnt fram á hvernig áhrifa hans gætir í höfundarverki Jóns.
Þriðji kafli hefst á því að greint er frá sérstöku samtali sem Jón Óskar á við Alexander Jóhannesson, eða öllu heldur bók hans Menningarsamband Frakka og Íslendinga (1943), þrjátíu árum eftir að sú bók kemur út og allnokkrum árum eftir að Alexander deyr. Annars greinir þriðji kaflinn að stærstum hluta frá þeim áhrifum sem Albert Camus hefur á texta Jóns og fagurfræði. Í því sambandi má nefna hvernig annálastíllinn úr Plágunni endurómar í minningabókum Jóns, einnig er samhljómurinn í viðhorfum Camus og Jóns til existensíalismans áhugaverður. Einnig fyrirlitu Camus og Jón Óskar mjög snemma, verandi dyggir vinstrimenn, ógnarstjórn Stalíns í Sovétríkjunum. Þá er í kaflanum greint frá stöðu endurminningabóka Jóns í samanburði við endurminningabækur höfunda á borð við Kristmann Guðmundsson og Halldór Laxness.
Fjórði kaflinn sýnir fram á að áhugi Jóns á sérstæðum persónum í mannlífinu vaknar snemma og birtir með ákveðnum hætti þá samlíðun sem Jón hafði ætíð með lítilmagnanum. Hér er kannað hvernig Jón kortleggur bóhemíuna í Reykjavík, í bæði viðleitni til að samsama sig henni en um leið til þess að gera lesendum endurminningbókanna ljóst hvar hann stendur sjálfur innan þeirrar sömu bóhemíu. Hér eru samanburðarfræði áberandi þáttur, því Jóni er skoðaður í samanburði við skáld hinnar íslensku bóhemíu, menn eins og t.d. Jóhannes Birkiland, Steindór Sigurðsson og Vilhjálm frá Skáholti. Leiðarstef kaflans er þó sú kenning að undir lok skáldskaparferils síns hafi Jón samsamað sig æ meira utangarðsmanninum í íslenskum veruleika, enda taldi hann sig löngum utangarðs og ekki njóta sannmælis í ýmsum menningarkreðsum þjóðarinnar, þannig hafi Jón að endingu séð sjálfan sig sem einskonar Sölva Helgason sinnar tíðar.This thesis investigates the status of the poet and translator Jón Óskar (1921-1998) within the Icelandic cultural field. Jón Óskar’s literary career is followed from the 1940s, from the time of his first published poem, and almost up to his death on October 20, 1998.
The years in which Jón Óskar was active in literary life were turbulent years both in Iceland and internationally. Jón Óskar published his first poems during the WWII and he was 23 years old when the Icelandic Republic was founded, at Þingvellir. He was at his peak as a writer at the time of the Cold War and the tension of that period in Iceland marks both his personality and his literary career. Jón Óskar belonged to the generation which was almost forced to take sides with or against military forces on Icelandic territory, after the US defence agreement in 1951. Moreover, Jón Óskar saw the '68 generation grow up and then betray the society and its own ideology. He witnessed the newborn rock and roll music evolve, the genre of music he despised; he watched foreign television stations, via satellite, broadcast directly from the 1991 Gulf War. Therefore, it is no exaggeration to state that Jón Óskar lived through an incredibly turbulent transition period.
During this era of rapid modernization and social change Jón Óskar writes his modernist unconventional poetry and early on in his career he is defined as one of the “atomic poets”. The generation of poets who made their appearance after the WWII came to be known as the “atomic poets”. The poets involved introduced a structural revolution in Icelandic literature and they are, rather inaccurately, sometimes referred to as the first modernists in Icelandic poetry. Jón Óskar also translates foreign poetry from a different era, mainly by the French symbolists, into Icelandic. Moreover, he sees his translations of such texts in harmony with the poetry of the Icelandic modernists, who use irregular form in days when form and structure is significantly changing. Thus, he establishes himself as a gatekeeper, being the one who controls access to the Icelandic literary field. For example, he is pivotal in introducting the work of the French symbolists and other French and Italian poets, who had been at their peak of fame in Europe decades earlier, to the Icelandic literary scene. The lateness of those foreign poets into Icelandic literature, through the gates of Jón Óskar and his translations, is actually like a microcosm of almost all of the author’s oeuvre – and also his presence, but his entire career is marked by lateness, late arrival, or hesitation. Such was his style and role, not in a negative sense though, because the thesis demonstrates that Jón Óskar can be characherised as a rear-guard (arrière-garde) author.
The thesis is divided into four main chapters, in which terms such as late arrival, hesitation and arrière-garde are guiding principles, as well as time distortion and delay or suspension – and indeed others of similar nature: in a nutshell, all concepts that in one way or another deal with time and man’s struggle with temporality.
The research question is fourfold:
1) What is Jón Óskar’s position within the Icelandic cultural field?
2) How does he appear as an arrière-garde author?
3) What are Jón Óskar’s characteristics according to: writing style, aesthetics, or poetics?
4) What were the influences on Jón Óskar’s method and aesthetics? And how did they evolve?
In the first chapter of the thesis, Jón Óskar is introduced and the methodology used in the thesis outlined. The study is the first extensive attempt to highlight Jón Óskar as a poet and translator, the first attempt to examine his role and status in the Icelandic cultural field, and the first attempt to analyse the roots of his writing. All of his writings, his translations and memoirs are under consideration in this chapter and are, as in other chapters of the thesis, the foundation of the study.
The second chapter focuses on the term arrière-garde, but this is the first time it is being used in a study of Icelandic literary and cultural history. The term is a tool to identify and analyse the method of Jón Óskar's writing and his aesthetic presence within the Icelandic cultural scene, the roots of the aesthetic involved as well as its nature.
Temporality is an important concept in this chapter, the concept of time points towards specific themes such as: Christian eschatology, mysticism, and French classicism – to name just a few. This section outlines how the works of T.S. Eliot influence Jón Óskar and how his writings feature elements that can be directly traced – to and beyond Eliot – to the English poet and philosopher T.E. Hulme. Henri Bergson’s importance is also underlined in this chapter, explaining how some of Bergson's ideas are echoed in Jón Óskar’s writings.
The third chapter begins with the reporting of a peculiar “conversation” that Jón Óskar has with Alexander Jóhannesson, or rather with his book Menningarsamband Frakka og Íslendinga (The French-Icelandic Cultural Union, 1943), thirty years after its publication, and several years after Alexander’s death. Above all, the third chapter focuses on the influence Albert Camus has on Jón Óskars’s writing and aesthetics. This includes how the chronicle-style from the Plague echoes in Jón's memoirs, moreover, it is also interesting to note the harmony in Camus’s and Jón’s views on existentialism. Also, Camus and Jón Óskar despised very early, being loyal leftists, Stalin’s threat regime in the Soviet Union. Finally, the chapter analyses the status of Jón Óskar’s memoirs, compared to the memoirs of authors such as Kristmann Guðmundsson and Halldór Laxness.
The fourth chapter reveals that Jón Óskar’s interests in peculiar characters within the society arise early and this highlights the compassion he always had with the underdog. The chapter examines how he maps the bohemian milieu in Reykjavik, both to identify himself with it, but at the same time to make the readers of the memoirs realize where he himself is situated within that same bohemia. Here, comparative studies are the key factor as Jón is compared to poets of the Icelandic bohemia, men such as Jóhannes Birkiland, Steindór Sigurðsson and Vilhjálmur frá Skáholti, among others. The theme of the chapter, however, is the theory that towards the end of his writing career Jón identified himself with the Icelandic cultural outsiders, more than ever. Hence, his opinion was that for long periods his writing did not receive the acclaim he thought it was due. And therefore, he saw himself as an outsider, on a par with the famous artist, Sölvi Helgason
Supervised-learning-enabled EM-driven development of low scattering metasurfaces
Get PDFThe recent advances in the development of coding metasurfaces created new opportunities to elevate the stealthiness of combat aircrafts. Metasurfaces, composed of optimized geometries of meta-atoms arranged as periodic lattices, are devised to obtain desired electromagnetic (EM) scattering characteristics, and have been extensively exploited in stealth applications to reduce radar cross section (RCS). They rely on the manipulation of backward scattering of electromagnetic (EM) waves into various oblique angles. Despite potential benefits, a practical obstacle hindering widespread metasurface utilization is the lack of systematic design procedures. Conventional approaches are largely intuition-inspired and demand heavy designer’s interaction while exploring the parameter space and pursuing optimum unit cell geometries. Another practical obstacle that hampers efficient design of metasurfaces is implicit handling of RCS performance. To achieve essential RCS reduction, the design task is normally formulated in terms of phase reflection characteristics of the unit cells, whereas their reflection amplitudes—although contributing to the overall performance of the structure—is largely ignored. A further practical issue is insufficiency of the existing performance metrics, specifically, monostatic and bistatic evaluation of the reflectivity, especially at the design stage of metasurfaces. Both provide a limited insight into the RCS reduction properties, with the latter being dependent on the selection of the planes over which the evaluation takes place. As a consequence of raised concerns, the existing design methodologies are still insufficient, especially in the context of controlling the EM wavefront through parameter tuning of unit cells. Furthermore, they are unable to determine truly optimum solutions. Therefore, we have introduced a novel machine-learning-based framework for automated and computationally efficient design of metasurfaces realizing broadband RCS reduction. We have employed a three-stage design procedure involving global surrogate-assisted optimization of the unit cells, followed by their local refinement. In its final stage, a direct EM-driven maximization of the RCS reduction bandwidth has been performed, facilitated by appropriate formulation of the objective function involving regularization terms. Moreover, to handle the combinatorial explosion in the design closure of multi-bit coding metasurfaces, a sequential-search strategy has been developed that enabled global search capability at the concurrent unit cell optimization stage. Latterly, the metasurface design task with explicit handling of RCS reduction at the level of unit cells has been introduced that has accounted for both the phase and reflection amplitudes of the unit cells. The design objective has been defined so as to directly optimize the RCS reduction bandwidth at the specified level (e.g., 10 dB) w.r.t. the metallic surface. The appealing feature of the said framework has consisted in its ability to optimize the RCS reduction bandwidth directly at the level of the entire metasurface as opposed to merely optimizing unit cell geometries. Besides, the obtained design has required minimum amount of tuning at the level of the entire metasurface. Lastly, a new performance metric for evaluating scattering characteristics of a metasurface, referred to as Normalized Partial Scattering Cross Section (NPSCS), has been proposed. The metric involved integration
of the scattered energy over a specific solid angle, which allows for a comprehensive assessment of the structure performance in a format largely independent of the particular arrangement of the scattering lobes. Our design methodologies have been utilized to design several instances of novel scattering metasurface structures with the focus on RCS reduction bandwidth enhancement and the level of RCS reduction. Experimental validations confirming the numerical findings have been also provided. To the best of the author’s knowledge, the presented study is the first systematic investigation of this kind in the literature and can be considered a step towards the development of efficient, low-cost, and more high performing scattering structures
Chitosan-hydroxycinnamic acid conjugates: Optimization of the synthesis and investigation of the structure activity relationship
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linkages, resulting in water-soluble conjugates after deprotection. Nineteen conjugates were obtained with
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(Rannis Grant No. 185188-053) and by a doctoral grant from the University of Iceland research fund.Pre-print (óritrýnt handrit