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Golden Lane Estate : A Real Part of the City / Golden Lane Estate : en integrerad del av stadenHildingsson, Karin January 2011 (has links)
This thesis proposes changes to the Golden Lane Estate in central London to integrate the public spaces within the estate with the surrounding city[M1] . The Golden[M2] Lane Estate is a modernist housing complex consisting of nine residential buildings with 564 flats. It was built as a council house project in 1952-1962 to satisfy the housing need after the Second World War. Current observations show that the public spaces at the Golden Lane Estate are mostly empty and spread over different levels increasing the spatial separation. Residents use the large open spaces for transit to or from their flats and visitors are rarely attracted. The modernist layout, where few people share space in front of the entrances to their flats, have affected the perceived ownership of public space at Golden Lane. It is neither perceived as private nor fully public. I have assumed that the residential buildings should stay intact. They are architecturally and historically valuable and serve their purpose well. The flats are popular and the estate was listed in 1992. The Golden Lane Leisure Centre is situated in the middle of the estate. In the listing record it is described as a chief example of the architects’ belief that a housing development should not just be a collection of flats but a real part of the city; it provides welcome facilities for those who live outside the estate as well as for residents. By reviving the Leisure Centre and turning unused garages into offices the two western public spaces are activated and restructured to be attractive to residents and visitors again. The revenue from the commercial spaces can finance an upgrade of the eastern public spaces to be a calm oasis where residents can realise their gardening dreams or office workers have their lunch. Today’s Golden Lane Estate can become a real part of the city with four attractive places adding value for residents, workers and visitors.
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Tempus Fugit : – En studie i Bud Powells musik och pianospel utifrån en konstnärlig bearbetning.Erlingsson, Jonatan January 2022 (has links)
<p>Repertoar:</p><p>Budpology- Jonatan Erlingsson</p><p>Strictly Confidential- Bud Powell</p><p>Tempus Fugit- Bud Powell</p><p>The Fruit- Bud Powell</p><p>Celia- Bud Powell</p><p>I´ll Keep Loving You- Bud Powell</p><p>I´ll Remember April- Gene de Paul</p><p></p><p>Medverkande Musiker:</p><p>piano, arrangemang, komposition - Jonatan Erlingsson</p><p>kontrabas - August Eriksson</p><p>trummor - Henrik Jäderberg</p><p>saxofon - Amanda Sedgwick</p><p>violin 1 - Tor Alvin Wika</p><p>violin 2 - Natasja Dluzewska</p><p>viola - Stina Ahlgren</p><p>cello - Åse-Maria Bygland Larsen</p>
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A study of aquatic fungi in Powell's sloughHsiao, Chao-chih 01 May 1969 (has links)
Aquatic fungi in-Powell's Slough were.studied in 1967 & 1968. Collections were made and water temperature, oxygen content & pH values were measured at weekly intervals. For collections, wire baskets containing substrata were submerged in water for one month. After collecting, substrata were brought to the laboratory. Identification was based on the keys of Sparrow, 1960. Aquatic fungi identified included seven orders, nine families, fifteen genera, and thirty species, from thirty-three collections of fifteen types of substrata. The substrata used in this study were: (i) fruits: apples, rose hips, plums, pears, haws; (ii) twigs: poplar, weeping willow, river birch, weeping white birch, pine, sumac, roseleaf mountain ash; (iii) others: algae, snake skin, fish head. Blastocladia pringsheimii was the predominant species, found on twelve different types of substrata. The number of species increased both in spring and in autumn, and decreased in summer.
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Habitat suitability and population characteristics of smallmouth bass and rock bass in the Powell River, VirginiaCummins, James L. Jr. 04 December 2009 (has links)
A survey of the population characteristics of smallmouth bass (Micropterus dolomieu), rock bass (Ambloplites rupestris), and habitat conditions were conducted in the Powell River, Virginia, to identify potential habitat limitations for these species. The study area consisted of three reaches, which were determined in 1987. The upstream reach was used to monitor effects of coal mining in the upper watershed on the Powell River. The midstream reach, which was below the North Fork Powell River, was used to monitor the possible effects of this tributary and its watershed. The downstream reach appeared to have been impacted by sedimentation less than either of the other reaches.
Habitat Suitability Index (HSI) models were used to identify habitat variables that were below optimum for these species in the Powell River, Virginia. Habitat sampling yielded HSI scores for smallmouth bass at each site ranging from 0.67 to 0.76, with a mean of 0.72; scores for rock bass ranged from 0.65 to 0.70, with a mean of 0.69. No trends in HSIs from upstream to downstream were evident. However, substratum, of which sand was dominant in pools, was the variable most frequently below optimum for smallmouth bass (Sl=0.21) and rock bass (SI=0.20). Values for sediment depth, embeddedness, waterborne sediment, and coal were collected in riffles, runs, and pools at 10 sites. Mean sediment depth in pools, embeddedness in riffles and runs, and waterborne sediment deposited in traps monthly in pools decreased from upstream to downstream; however, waterborne sediment in runs did not decrease. Content (by weight) of coal wastes in the substratum did not decrease from upstream to downstream. The embeddedness index in pools (= 1.0), riffles, and runs was not significantly different among the three river reaches.
No differences in population abundance, biomass estimates, age and growth, or relative weights (Wr) of smallmouth bass and rock bass were found among the three river reaches. Population estimates of smallmouth bass (34.3/ha) and rock bass (116.6/ha) were lower than those in many other streams in the U.S. Catch-per-unit-effort and biomass of smallmouth bass (2.9/h, 2.6 kg/ha) and rock bass (6.6/h, 2.2 kg/ha) also were lower than those in most other streams. A total of 70 stomachs of smallmouth bass and 166 stomachs of rock bass was examined from fish collected between July 1988 and October 1989. Diets for each species, primarily crayfish and insects, showed no apparent differences among the three river reaches. Abundance of crayfish and hellgrammites were compared; greatest hellgrammite abundance was in the downstream reach (P = 0.032), and there were no significant differences in crayfish abundance among the three river reaches.
HSI values showed no significant correlation with catch-per-unit-effort for smallmouth bass or rock bass. No significant correlation was found among sediment depth, catch-per-unit effort, biomass or relative weight of smallmouth bass and rock bass. No correlation was found between the embeddedness index in riffles and biomass of rock bass. There was a significant negative correlation between the embeddedness index in riffles and relative weight of smallmouth bass (P=0.016); however, no correlation existed between the embeddedness index and relative weight of rock bass. There was a significant negative correlation between the embeddedness index in riffles and growth of smallmouth bass (P=0.016); however, there was a significant positive correlation between the embeddedness index and growth of rock bass. There was a significant positive correlation between the embeddedness index in riffles and both hellgrammite abundance (P=0.031) and crayfish abundance (P=0.052) in riffles. No significant correlation was found between the amount of sediment deposited in pools and catch-per-unit-effort of smallmouth bass and rock bass. No significant correlation existed between the amount of sediment deposited in runs and biomass of rock bass. In addition, crayfish density was not correlated with relative weight of smallmouth bass or rock bass. With the available documentation that links population characteristics of smallmouth bass and rock bass to habitat, it is evident that habitat is usually the limiting factor in determining population characteristics; however, there was no significant trend in the correlations presented above.
Habitat for smallmouth bass and rock bass in the Powell River, Virginia was suboptimum and sand was the dominant substratum in pools. Population estimates, catch-per-unit-effort, and biomass of smallmouth bass and rock bass in the Powell River are low compared to other U.S. streams. Although it appears that sedimentation has degraded habitat of smallmouth bass and rock bass and contributed to reduced population levels of these species in the Powell River, Virginia, my results were not statistically different among sites with measurable differences in sedimentation. / Master of Science
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Toxicity of zinc, copper, and sediments to early life stages of freshwater mussels in the Powell River, VirginiaMcCann, Mary T. 11 July 2009 (has links)
The decline in mussel fauna of the Powell River has been attributed to extensive mining activities in headwater streams of Wise and Lee counties, Virginia. Surface mining causes erosion, sedimentation, and contamination of water with toxic substances from coal washing and waste piles. Historical water quality data of the Powell River have documented concentrations of metals at levels determined to be toxic to molluscs, specifically zinc (Zn) and copper (Cu). Acute toxicity tests with Zn, Cu, and mixtures of these two metals were conducted with glochidia and juvenile freshwater mussels. Effects of varying conditions such as water source, temperature, length of exposure, species, and lifestage were determined. Additionally, the effects of Powell River sediment on survival and growth of juvenile mussels were evaluated.
The Cumberland moccasin shell (Wedionidus conradicus) was the most sensitive species tested, with 24-hr and 48-hr LC50 values for glochidia ranging from 423 to 725 μg Zn/L. Glochidia of the pheasantshell (Actinonaias pectorosa) exhibited LC50 values from 274 to 2886 μg Zn/L, depending on test conditions. Similar results were obtained for glochidia of the rainbow (Villosa iris), with LC50 values ranging from 577 to 4123 μg Zn/L. Juveniles were more sensitive, with 48-hr LC50 values ranging from 360 to 1885 μg Zn/L for A. pectorosa, and 339 to 1122 μg Zn/L for V. iris, depending on test conditions. Juvenile mussels were affected by Zn at lower concentrations as evidenced by valve gaping and a swollen and nonresponsive foot. Copper was 5 to 15 times more toxic than Zn, with 48-hr LC50 values ranging from 52 to 156 μg Cu/L, and ECS5O values ranging from 25 to 115 μg Cu/L for juveniles of A. pectorosa. Copper appeared to exert a different toxic mode of action, as evidenced by closed valves and reduced siphoning. In general, sensitivities of early life stages of mussels to Zn and Cu increased with higher temperature, soft water, and length of exposure. At certain concentrations, Zn seemingly had an antagonistic effect (less than additive) when mixed with Cu. This effect was evidenced by reduced mortality of juveniles in Cu solutions when Zn was added at concentrations of about 400 to 800 μg/L. However, this antagonistic effect was not reflected in the percent of juveniles affected, which increased continuously with increasing metal concentrations.
Glass beads were found unsuitable as a control substratum for use in sediment testing with juvenile mussels. Results of sediment tests indicated that sediment in some areas of the Powell River may be toxic to juvenile mussels, and that toxicity may be linked to water quality. After 10 days, survival of juveniles in sediment collected downstream of a coal processing plant was significantly lower than survival in sediment upstream of the plant (p = 0.01). Further, survival in sediments with dechlorinated tap water was significantly higher than survival in sediment with river water (p = 0.0002). After 20 and 30 days, survival was similar among sites and water types. High metal concentrations in the river water appeared to contribute to toxicity, because juveniles in tap water displayed consistently better growth, and initially better survival than juveniles in river water and sediment. This toxicity was not apparent in sediments collected from the same sites less than two months later, suggesting the character of the sediments may change as new suspended sediment is deposited.
The USEPA water quality criteria for Zn (adjusting for water hardness) are 174 μg/L (acute) and 158 μg/L (chronic), whereas copper criteria are set at 28 μg/L (acute) and 18 μg/L (chronic). Powell River water samples collected during 1991 contained concentrations of Zn and Cu exceeding these criteria, as well as concentrations shown to have adverse effects on mussel populations. Results suggest that some metals are introduced into the river system in runoff, whereas Cu is being introduced as an episodic event. Intensive monitoring of water quality is needed to identify specific sources of metal pollution. If levels of heavy metal concentrations remain high, then the declining mussel populations of the Powell River will not recover, and endangered species may be extirpated from Virginia. / Master of Science
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A Quantitative Survey of the Freshwater Mussel Fauna in the Powell River of Virginia and Tennessee, and Life History Study of Two Endangered Species, Quadrula sparsa and Quadrula intermediaJohnson, Matthew 26 May 2011 (has links)
Qualitative and quantitative sampling was conducted along a 165 km reach of the river from PRKM 269.4 near Dryden, VA to PRKM 104.8 near Harrogate, TN. Twenty-nine species were observed throughout the entire river, and the highest diversity of 23 species was collected at PRKM 152.6. Mussel abundances (mussels/person-h and mussels/m2) ranged from 0.33 to 21.98 mussels/person-h and 0.00 to 2.24 mussels/m2. Recent recruitment (individuals < 40 mm, depending on the species) was observed for 15 species, including the endangered Epioblasma brevidens, Lemiox rimosus, and Quadrula intermedia. The greatest number of species (6) with evidence of recent recruitment also was found at PRKM 152.6.
Data from the quantitative survey were used to simulate several sampling protocols that could be used to develop a long-term monitoring program for the Powell River. Five sites, PRKMs 197.9, 171.4, 159.6, 152.6, and 129.4, were selected for long-term monitoring because of high mussel densities and species richness. Six sampling protocols were simulated using the statistical program MONITOR to determine which protocols, if any, could monitor statistically significant changes in mussel abundance at rates + 10%. Each of the simulated sampling protocols lasted between 15 and 30 y, and employed quantitative sampling at 3 to 5 y intervals. None of the sampling protocols simulated during this study were able to detect declines in mussel abundance < 10%. Two sampling programs were able to detect increases in mussel abundance > 6% when the level of significance was > 0.10, and four sampling programs were able to detect a density increase of > 8% when the level of significance was 0.05.
Despite the inability to monitor declines in mussel abundances, a long-term monitoring program is needed for the Powell River. Because qualitative sampling has been repeatedly shown to document species presence more effectively than quantitative sampling, it should be used to monitor changes in species presence and distribution. Quantitative sampling should be employed to monitor juvenile recruitment and changes in size-class structure of populations. Quantitative sampling also should be conducted to monitor overall mussel abundance at sites. Despite the inability to statistically detect changes in mussel density in the Powell River, quantitative sampling can provide valuable information, and the data collected can be used to qualitatively monitor changes in total density at sites.
Both species share a similar distribution in the Powell River. Eighteen specimens of Quadrula sparsa were collected between PRKM 230.9 and 152.6, and 68 individuals of Q. intermedia were collected between PRKM 230.9 and 129.4. The highest density of each species was collected at PRKM 152.6, and recent recruitment was observed at PRKMs 152.6 and 153.4. Fresh-dead and relic shells of both species were thin-sectioned to determine individual growth rate and life span. These species complete the majority of their growth during the first 10 y of life, and likely live for a total of 40 to 50 y. One gravid female of Q. intermedia was collected during this study, but no gravid females of Q. sparsa were observed. / Master of Science
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Coal waste deposition and the distribution of freshwater mussels in the Powell River, VirginiaWolcott, Lisa Terwilliger 03 March 2009 (has links)
A survey of the freshwater mussel fauna was conducted in the Powell River, Virginia, to identify critical habitat for endangered species, quantify substratum composition and coal waste deposition, and to assess population trends during the last half century. Mussels were collected as far upstream as Powell River Mile (PRM) 167.4 near Dryden, Virginia. Endangered species were collected up to PRM 144.6 at Jonesville, Virginia. The sites with greatest diversity were located furthest downstream, and there appeared to be a general decline in the number of species and diversity of mussels from downstream to upstream. Mussel densities also declined proceeding upstream, and specimens were rare above PRM 158.3 near Pennington Gap, Virginia. The highest density occurred at PRM 123.0 near the Tennessee-Virginia border, with 24 mussels/m². Collections per unit effort of sampling concurred with quadrat surveys, indicating a decline in abundance and diversity upstream. Length frequency distributions of the muckets Actinonaias pectorosa and A. ligamentina indicated an absence of smaller mussels at most sites.
Sediment samples, collected in riffles at 10 sites to determine particle size distributions and the amount of coal, showed no apparent trends in waste coal from downstream to upstream; however, there were significant negative correlations between PRM location and various fractions of the substratum, indicating a longitudinal sorting of smaller size fractions. Percentages of very fine to medium sand, silt, and coal show marked increases downstream of the North Fork Powell River confluence (PRM 156.6) at Pennington Gap, Virginia. Mussel density had a slightly positive correlation with percent silt (r²=0.346, p=0.0736) but was not correlated with percent coal.
Juvenile mussels of Villosa iris were placed on several types of substratum to determine differences in survival. In laboratory experiments, survival of juveniles on coal silt sometimes did not differ from that of juveniles without substratum (survival close to 100%). Survival of juveniles without substratum (93.9%), however, was significantly higher than survival (30.0-63.2%) on three sediment types from the Powell River (p< .001). In field experiments, there was a marginally significant difference in survival of juveniles between two sites (p =.070), with higher survival (47.7%) in sediments from Poteet Ford (PRM 144.6). Survival of juveniles was similar in all laboratory and field experiments.
A decline in density of the mussel fauna in the Powell River over the past 15 years was apparent when compared to previous data. Contamination and siltation from coal washing facilities and abandoned mine lands are suspected of contributing to this decline. / Master of Science
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Exile, authorship, and 'the good German' : a reconsideration of the screenplays and novels of Emeric PressburgerMcDonald, Caitlin Elizabeth January 2018 (has links)
Despite being an equal in the most significant partnership in British cinema, Emeric Pressburger has largely been overshadowed by his long term collaborator Michael Powell in both critical and academic studies. While there have been countless books on Powell and Pressburger as a team, those who have sought to separate the partnership have, until now, focussed almost exclusively on Powell. This thesis will attempt to redress the balance within Powell and Pressburger scholarship and attempt to break away from director-centric film studies. It will aim to examine Pressburger’s morally ambiguous characters, such as the recurring “good German” and his propensity to humanise characters who would normally be termed evil or corrupt, in conjunction with the central themes of displacement and exile within Pressburger’s screenplays and novels. The thesis will also utilise both unpublished and unfilmed material and demonstrate that the study of these works that exist only in archives provide a greater insight into the working practises of authors and filmmakers, while providing a valuable point of comparison to their more widely known works. Specifically, this thesis will address four separate aspects of Pressburger’s canon. First, it will discuss Pressburger’s war films which he made with Powell, which have suffered to an extent from neglect by many Archers’ scholars. It is clear that Pressburger’s key hallmarks and mirroring of his own experiences during the war can be seen to develop within these works and provide an ideal point of comparison with that of his later projects such as his novels. Chapter two will then examine the often overlooked filmed operetta, <i>Oh ... Rosalinda!! </i>(1955) along with Pressburger’s unfilmed screenplay <i>The Golden Years</i> (1951) a biopic of Richard Strauss, and provide a comparison to demonstrate the manner in which Pressburger’s love of opera overlapped with his development of complex characters and response to the war. Chapter three will analyse Pressburger two published novels, both of which have been largely ignored by both cinema and literary critics. Through the study of these novels, the difference in approach after the transition from screenwriter to novelist will be examined, along with the further development of his seeming neutrality in the portrayal of morally unsound characters. Chapter four will then focus on Pressburger’s two unpublished novels, <i>The Unholy Passion</i> and <i>A Face like England</i>, with consideration of Pressburger’s developing ideas of morality and forgiveness in his later years. In conclusion, by closely examining works that have been overlooked by Powell and Pressburger scholars, the thesis will shed new light on Pressburger, both as a filmmaker and an author and demonstrate the complexities of both his characters and his writing.
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O violão de 8 cordas como instrumento acompanhador do canto popular brasileiroCouteiro, Clidney de Amorim 04 April 2012 (has links)
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Previous issue date: 2012-04-04 / The purpose of this research is the elaboration of four arranges for the 8-strings guitar,
aiming the demonstration and exploration of the potentialities of this instrument in the
accompaniment of popular singing. In order to compose this article transcriptions of the songs
“Consolação” by Baden Powell and Vinicius de Moraes (1913-1980) and “Capitu” by Luiz
Tatit were used, which provided the base for the creation of the four arranges. Besides that,
the forms of utilization of the 7-strings guitar in “choro” and “samba” were investigated, as
well as the use of the bass beat in MPB, among other musical constructions typical of the
guitar role in the tradition of MPB as a way of subsidize the proposed arranges. / Esta pesquisa tem como proposta a elaboração de quatro arranjos para o violão de 8
cordas, objetivando demonstrar e explorar as potencialidades desse instrumento no
acompanhamento do canto popular. Para a realização deste artigo foram utilizadas
transcrições das canções “Consolação” de Baden Powell e Vinicius de Moraes (1913-1980) e
“Capitu” de Luiz Tatit (1951), que forneceram a base para a criação dos quatro arranjos. Além
disso, foram investigadas as formas de utilização do violão de 7 cordas no choro e no samba,
bem como o uso das “levadas” do contrabaixo na MPB, entre outras construções musicais
típicas do papel do violão na tradição da MPB como forma de subsidiar os arranjos propostos.
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Acceleration and new analysis of convex optimization algorithmsLiu, Lewis 07 1900 (has links)
Ces dernières années ont vu une résurgence de l’algorithme de Frank-Wolfe (FW) (également connu sous le nom de méthodes de gradient conditionnel) dans l’optimisation clairsemée et les problèmes d’apprentissage automatique à grande échelle avec des objectifs convexes lisses. Par rapport aux méthodes de gradient projeté ou proximal, une telle méthode sans projection permet d’économiser le coût de calcul des projections orthogonales sur l’ensemble de contraintes. Parallèlement, FW propose également des solutions à structure clairsemée. Malgré ces propriétés prometteuses, FW ne bénéficie pas des taux de convergence optimaux obtenus par les méthodes accélérées basées sur la projection. Nous menons une enquête dé- taillée sur les essais récents pour accélérer FW dans différents contextes et soulignons où se situe la difficulté lorsque l’on vise des taux linéaires globaux en théorie. En outre, nous fournissons une direction prometteuse pour accélérer FW sur des ensembles fortement convexes en utilisant des techniques d’intervalle de dualité et une nouvelle notion de régularité.
D’autre part, l’algorithme FW est une covariante affine et bénéficie de taux de convergence accélérés lorsque l’ensemble de contraintes est fortement convexe. Cependant, ces résultats reposent sur des hypothèses dépendantes de la norme, entraînant généralement des bornes invariantes non affines, en contradiction avec la propriété de covariante affine de FW. Dans ce travail, nous introduisons de nouvelles hypothèses structurelles sur le problème (comme la régularité directionnelle) et dérivons une analyse affine invariante et indépendante de la norme de Frank-Wolfe. Sur la base de notre analyse, nous proposons une recherche par ligne affine invariante. Fait intéressant, nous montrons que les recherches en ligne classiques utilisant la régularité de la fonction objectif convergent étonnamment vers une taille de pas invariante affine, malgré l’utilisation de normes dépendantes de l’affine dans le calcul des tailles de pas. Cela indique que nous n’avons pas nécessairement besoin de connaître à l’avance la structure des ensembles pour profiter du taux accéléré affine-invariant.
Dans un autre axe de recherche, nous étudions les algorithmes au-delà des méthodes du premier ordre. Les techniques Quasi-Newton approchent le pas de Newton en estimant le Hessien en utilisant les équations dites sécantes. Certaines de ces méthodes calculent le Hessien en utilisant plusieurs équations sécantes mais produisent des mises à jour non symétriques. D’autres schémas quasi-Newton, tels que BFGS, imposent la symétrie mais ne peuvent pas satisfaire plus d’une équation sécante. Nous proposons un nouveau type de mise à jour symétrique quasi-Newton utilisant plusieurs équations sécantes au sens des moindres carrés. Notre approche généralise et unifie la conception de mises à jour quasi-Newton et satisfait des garanties de robustesse prouvables. / Recent years have witnessed a resurgence of the Frank-Wolfe (FW) algorithm, also known as conditional gradient methods, in sparse optimization and large-scale machine learning problems with smooth convex objectives. Compared to projected or proximal gradient methods, such projection-free method saves the computational cost of orthogonal projections onto the constraint set. Meanwhile, FW also gives solutions with sparse structure. Despite of these promising properties, FW does not enjoy the optimal convergence rates achieved by projection-based accelerated methods.
On the other hand, FW algorithm is affine-covariant, and enjoys accelerated convergence rates when the constraint set is strongly convex. However, these results rely on norm-dependent assumptions, usually incurring non-affine invariant bounds, in contradiction with FW’s affine-covariant property. In this work, we introduce new structural assumptions on the problem (such as the directional smoothness) and derive an affine in- variant, norm-independent analysis of Frank-Wolfe. Based on our analysis, we pro- pose an affine invariant backtracking line-search. Interestingly, we show that typical back-tracking line-search techniques using smoothness of the objective function surprisingly converge to an affine invariant stepsize, despite using affine-dependent norms in the computation of stepsizes. This indicates that we do not necessarily need to know the structure of sets in advance to enjoy the affine-invariant accelerated rate. Additionally, we provide a promising direction to accelerate FW over strongly convex sets using duality gap techniques and a new version of smoothness.
In another line of research, we study algorithms beyond first-order methods. Quasi-Newton techniques approximate the Newton step by estimating the Hessian using the so-called secant equations. Some of these methods compute the Hessian using several secant equations but produce non-symmetric updates. Other quasi- Newton schemes, such as BFGS, enforce symmetry but cannot satisfy more than one secant equation. We propose a new type of quasi-Newton symmetric update using several secant equations in a least-squares sense. Our approach generalizes and unifies the design of quasi-Newton updates and satisfies provable robustness guarantees.
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