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Mitt folkets hus befinner sig i Sandviken, ett mindre fritidshusområde norr om Södertälje. Under COVID 19 pandemin har diskussionen och behovet kring flexibla arbetsplatser och önskan om en mer naturnära livsstil ökat. I mitt projekt har jag undersökt hur en ny typ av distansarbetsplats som kombinerar arbete med rekreation skulle kunna se ut. Projektets gestaltning inspireras av bebyggelsen och bryggorna i Sandviken som är varierande och ibland spontan. Jag vill att byggnaden ska variera i sitt uttryck men genomgående följa samma grundläggande konstruktionsprincip. En stomme som förändrar sitt uttryck beroende på var man befinner sig i byggnaden. En annan viktig riktlinje är att byggnaden ska relatera till kroppen och platsens skala för att inte uppfattas som allt för stor eller monumental. / My project is located in Sandviken, an area north of Södertälje. A small place with mostly holiday homes. During the COVID 19 pandemic a discussion about flexible workplaces and the need for more outdoor activities have grown. My project explores what a new type of workplace that combines work and recreation could look like. The design is inspired by the local buildings and boat docks in Sandviken, which often varies in looks and in some cases feel very spontaneous. I want my building to vary in expression but follow the same principles of construction throughout. A structure which allow for a change in how it feels depending on where you are in the building. It has aslo been important for me that the size of the building relates to the scale of the site and the human body and to not make a monumental impression.

The problem with which this study was concerned was that of comparing three methods of executing the competitive breaststroke turn and their effects on swimming fifty yards. The turns utilized were the AAU, NCAA, and somersault. A related purpose was that of analyzing the time a breaststroke competitor was to be submerged on the glide following the turn. One hundred four male, senior swimmers from teams in the Arkansas AAU were rated on five components of the breaststroke. Twenty-nine advanced and thirty novice breaststrokers were selected from this group to participate in this study. The subjects were timed for a distance of fifty yards using, in order, the AAU, NCAA, and somersault turns.

Embora muitos estudos tenham investigado a contribuição da força propulsora na velocidade de nadadores, a maioria das pesquisas se restringiu ao estilo crawl e no nado como um todo. Sendo assim, o objetivo do presente estudo foi mensurar e comparar a força propulsora e o desempenho de velocidade nos quatro estilos competitivos e verificar a relação entre elas durante o nado completo, o nado somente de pernas e o nado somente de braços em nadadores competitivos. Participaram do estudo 37 nadadores do sexo masculino com experiência competitiva de no mínimo dois anos, com idade entre 15 e 19 anos. A amostra foi dividida pelos estilos borboleta (n=9), costas (n=7), peito (n=9) e crawl (n=12). Foram medida as variáveis de força propulsora (VFP) no nado atado (NA) nas seguintes situações; força propulsora máxima de nado em 10 segundos (FPM10), força propulsora máxima de pernas em 10 segundos (FPMp), força propulsora máxima de braços em 10 segundos (FPMb), força propulsora máxima de nado em 25 segundos (FPM25) força propulsora média de nado em 25 segundos (FPm25). Também foi mensurada a velocidade nas metragens de 15 e 50 metros (V15 e V50). Cada nadador realizou os testes de força e velocidade nos principais estilos de competição. Os resultados demonstraram correlações entre as VFP com a velocidade para os quatro estilos competitivos no nado completo (entre r=0,62 e 0,97), na força propulsora de pernas nos estilos costas e crawl (r=, 0,77, 0,73 e 0,72) e para a força propulsora de braços no estilo crawl (r=0,73). O estilo peito se correlacionou de maneira moderada negativamente (r=, -0,69, -0,75, -0,76 e -0,77) com a FPM10, FPM25, FPM25 e FPm25. Conclui-se que a força propulsiva apresentou relação com a velocidade nos quatro estilos competitivos e que tal relação é melhor no nado completo quando comparada aos membros inferiores e superiores / Although many studies have investigated the contribution of propulsive force in speed of swimmers, most studies has been restricted to crawl and complete swimming. So, the objective of this study was to measure and compare the propulsive force and speed performance on all four competitive strokes and the relation between them during complete swimming, propulsive force of the legs and of the arms. The study included 37 male swimmers competitive with at least two years, with ages between 15 and 19 years old. The sample was divided by styles butterfly (n = 9), back (n = 7), breast (n = 9) and crawl (n = 12). We analyze the propulsive force variables (VFP) in tethered swimming (NA) in situations: maximum propulsive force of swimming in 10 seconds (FPM10) maximum propulsive force of legs in 10 seconds (FPMp), maximum propulsive force of arms in 10 seconds (FPMb), maximum propulsive force of swimming in 25 seconds (FPM25) mean propulsive force of swimming in 25 seconds (FPm25). Also the speed was measured at distances of 15 and 50 meters (V15 and V50). Each swimmer performed the tests of strength and speed in the main styles of competition. The results showed correlations between VFP with speed for the four competitive swimming in complete swimming (between r = 0.62 and 0.97), in the propulsive force of legs in the back and crawl styles (r = 0.77, 0.73 and 0.72) and the propulsive force of arms in the crawl (r = 0.73). The breaststroke showed moderate negative correlation (r = -0.69, -0.75, -0.76 and -0.77) with FPM10, FPM25, and FPM25 FPm25. It is concluded that the propulsive force was related to the speed in four competitive and that this relationship is better in comparison to the complete swimming upper and lower limbs

No description available.

This thesis examined the benefits of physiological and performance testing of elite swimmers. The study considered the following research questions: the degree to which physiological and performance measures in training contribute to swimming performance; sources and magnitude of variability in testing, training and competition performance; the magnitudes of changes in test measures during routine training; and the reliability, validity and utility of miniaturised and automated smart sensor technology to monitor the stroke and performance times of swimmers in training. The experimental approach involved the retrospective analysis of five years of physiological and performance testing of elite level swimmers, the development of a new accelerometry-based smart sensor device to monitor swimmers in the pool, a cross-sectional study comparing the physiological and performance responses of swimmers of different levels, and the effects of an intensive 14-day training program on submaximal physiological and performance measures. Collectively, the outcomes of these studies provide a strong justification for the physiological and performance testing of elite swimmers, a quantitative framework for interpreting the magnitude of changes and differences in test scores and sources of variation, and highlight the potential utility of new smart sensor technology to automate the monitoring of a swimmer�s training performance. The first study (Chapter 2) characterises the changes and variability in test performance, physiological and anthropometric measures, and stroke mechanics of swimmers within and between seasons over their elite competitive career. Forty elite swimmers (24 male, 16 female) performed a 7 x 200-m incremental swimming step test several times each 6-month season (10 � 5 tests, spanning 0.5 to 6.0 y). Mixed linear modeling provided estimates of change in the mean and individual responses for measures based on submaximal performance (fixed 4-mM lactate), maximal performance (the seventh step), and lean mass (from skinfolds and body mass). Submaximal and maximal swim speed increased within each season from the pre to taper phase by ~2.2% for females and ~1.5% for males (95% confidence limits �1.0%), with variable contributions from stroke rate and stroke length. Most of the gains in speed were lost in the off-season, leaving a net average annual improvement of ~1.0% for females and ~0.6% for males (�1.0%). For submaximal and maximal speed, individual variation between phases was �2.2% and the typical measurement error was �0.8%. In conclusion, step test and anthropometric measures can be used to confidently monitor progressions in swimmers in an elite training program within and between seasons. The second study (Chapter 3) quantified the relationship between changes in test measures and changes in competition performance for individual elite swimmers. The primary question addressed was whether test measures could predict a swimmers performance at the major end-of-season competition. The same sample group as in Study 1 was examined. A 7 x 200-m incremental swimming step-test and anthropometry were conducted in up to four training phases each season. Correlations of changes in step-test and anthropometric measures between training phases between and within seasons, with changes in competition performance between seasons, were derived by repeated-measures mixed modeling and linear regression. Changes in competition performance were best tracked by changes in test measures between taper phases. The best single predictor of competition performance was skinfolds for females (r = -0.53). The best predictor from the step-test was stroke rate at 4-mM lactate (females, r = 0.46; males, r = 0.41); inclusion of the second-best step-test predictor in a multiple linear regression improved the correlations marginally (females, r =0.52 with speed in the seventh step included; males, r = 0.58 with peak lactate concentration included). Changes in test measures involving phases other than the taper provided weak and inconclusive correlations with changes in performance, possibly because the coaches and swimmers took corrective action when tests produced poor results. In conclusion, a combination of fitness and techniques factors are important for competitive performance. The step test is apparently a useful adjunct in a swimmer�s training preparation for tracking large changes in performance. These initial studies identified stroke mechanics as a major determinant of a swimmer�s performance. Chapter 4 details the development of a small tri-axial accelerometry-based smart sensor device (the Traqua) that enables continual monitoring of various performance/stroke characteristics in swimming. The initial focus was to develop a device that automated the detection of a swimmer�s movements, specifically lap times, stroke rate and stroke count. The Traqua consists of a tri-axial accelerometer packaged with a microprocessor, which attaches to the swimmer at the pelvis to monitor their whole body movements while swimming. This study established the failure/error rate in the first generation algorithms developed to detect the swimming-specific movements of stroke identification, laps (start, turn and finish), and strokes (stroke count and stroke rate) in a cohort of 21 elite and sub-elite swimmers. Movements were analysed across a range of swimming speeds for both freestyle and breaststroke. These initial algorithms were reasonably successful in correctly identifying the markers representing specific segments of a swimming lap in a range of swimmers across a spectrum of swimming speeds. The first iteration of the freestyle algorithm produced error-rates of 13% in detection of lap times, 5% for stroke rate, and 11% for stroke count. Subsequent improvements of the software reduced the error rate in lap and stroke detection. This improved software was used in the following two studies. The next study (Chapter 5) evaluated the reliability and validity of the Traqua against contemporary methods used for timing, stroke rate and stroke count determination. The subjects were 14 elite and 10 sub-elite club-level swimmers. Each swimmer was required to swim seven evenly paced 200-m efforts on a 5-min cycle, graded from easy to maximal. Swimmers completed the test using their main competitive stroke (21 freestyle, 3 breaststroke). Timing was compared for each 50-m lap and total 200-m time by electronic touch pads, video coding, a hand-held manual stopwatch, and the Traqua. Stroke count was compared for video coding, self-reported counting, and the Traqua, while the stroke rate was compared via video coding, hand-held stopwatch, and the Traqua. Retest trials were conducted under the same conditions 7 d following the first test. All data from the Traqua presented in this and the subsequent studies were visually inspected for errors in the automated algorithms, where the algorithms had either failed to correctly identify the start, turn, finish or individual strokes and corrected prior to analysis. The standard error of the estimate for each of the timing methods for total 200 m was compared with the criterion electronic timing. These standard errors were as follows: Traqua (0.64 s; 90% confidence limits 0.60 � 0.69 s), Video (0.52 s; 0.49 � 0.55 s); Manual (0.63 s; 0.59 � 0.67 s). Broken down by 50-m laps, the standard error of the estimate for the Traqua compared with the electronic timing for freestyle only was: 1st 50-m 0.35 s; 2nd and 3rd 50-m 0.13 s; 4th 50-m 0.65 s. When compared with the criterion video-coding determination, the error for the stroke count was substantially lower for the Traqua (0.6 strokes.50 m-1; 0.5 � 0.6 strokes.50 m-1) compared to the self-reported measure (2.3 strokes.50 m-1; 2.5 � 2.9 strokes.50 m-1). However, the error for stroke rate was similar between the Traqua (1.5 strokes.min-1; 1.4 � 1.6 strokes.min-1) and the manual stopwatch (1.8 strokes.min-1; 1.7 � 1.9 strokes.min-1). The typical error of measurement of the Traqua was 1.99 s for 200-m time, 1.1 strokes.min-1 for stroke rate, and 1.1 strokes.50 m-1 for stroke count. In conclusion, the Traqua is comparable in accuracy to current methods for determining time and stroke rate, and better than current methods for stroke count. A substantial source of error in the Traqua timing was additional noise in the detection of the start and finish. The Traqua is probably useful for monitoring of routine training but electronic timing and video are preferred for racing and time trials. Having established the reliability and validity of the Traqua, Chapter 6 addressed the ability to discriminate the pattern of pacing between different levels of swimmers in the 7 x 200-m incremental step test. This study also sought to quantify the differences in pacing between senior and junior swimmers. Eleven senior elite swimmers (5 female, 6 male) and 10 competitive junior swimmers (3 female, 7 male) participated in this study. Each swimmer was required to swim seven evenly paced 200-m freestyle efforts on a 5-min cycle, graded from easy to maximal. The Traqua was used to measure time, stroke rate and stroke count. The senior swimmers were better able to descend in each of the 200-m efforts. Overall the senior swimmers were ~2-3 s per 50 m faster than the junior swimmers. Both groups were fastest in the first 50-m lap with the push start. The senior swimmers then descended the 50- m time for each of the subsequent laps, getting ~0.5 s faster per lap, with the final lap the fastest. In contrast, the junior swimmers swam a similar time for each of the subsequent laps. The junior swimmers were marginally more variable in their times (coefficient of variation: ~2%) compared with the senior swimmers (~1.8%). In comparison to junior swimmers, the senior swimmers in this study were faster, adopted a more uniform negative split strategy to pacing within a 200-m effort, and were more consistent in reproducing submaximal and maximal swimming speeds. The final study (Chapter 7) analysed the effect of 14-d of intensive training on the reproducibility of submaximal swimming performance in elite swimmers. Submaximal physiological and performance testing is widely used in swimming and other individual sports but the variability in test measures, and the effects of fatigue, during intensive training have surprisingly not been quantified systematically. Seven elite swimmers (3 male and 4 female) participated in an intensive 14-d training camp one month prior to the National championships. The aim of the study was to characterise the intra-session, daily and training block variability of submaximal swimming time, physiological and stroke characteristics in elite swimmers. The swimmers performed a specified submaximal 200-m effort in most sessions, after the warm-up and at the end of the session for both morning and afternoon sessions. During the efforts, swimming time and stroke mechanics were measured and physiological measures were recorded immediately on completion. The Traqua was worn by all swimmers in every training session. Mixed linear modeling was used to provide estimates of changes in the mean and individual responses (within-athlete variation as a coefficient of variation) for all measures. The swimmers were moderately slower (1.4%; �1.4%) over the 14-d training camp. The mean submaximal 200-m effort was very likely to be faster (0.7%; confidence limits �0.7%) in the afternoon compared with the morning session. The females were more variable in their submaximal performance times (CV=2.6%) than the male swimmers (1.7%). Blood lactate concentration was almost certainly lower (-23%; �10%) following higher volume in the previous session; however a higher intensity workout the previous session almost certainly leads to higher lactate (21%; �15%) in the current session. Considered together, these results indicate that the 200-m submaximal test is useful in monitoring submaximal physiological and performance measures and the negative effects of cumulative fatigue. In conclusion, changes in the physiological and performance measures derived from the poolbased progressive incremental step test are moderately correlated with changes in end-ofviii. season competition performance. The magnitudes of changes and differences in test measures between phases within a season, from season to season, and between males and females, established in this study can be applied to similar elite level swimmers preparing for major competition. The quantification of typical error of the same measures demonstrates that coaches and scientists can distinguish real and worthwhile improvements using the 7 x 200-m step test. Continual pool-based monitoring with the automated smart sensor Traqua device may provide more accurate and detailed information about a swimmer�s training adaptation than current fitness tests and monitoring methods. Finally, submaximal testing in trained swimmers is useful in monitoring progress in physiological and performance measures, and the impact of cumulative fatigue during an intensive period of training. Collectively, the outcomes of these studies indicate that routine physiological and performance testing can provide measurable benefits for elite swimmers and their coaches.

Thesis (M. Arch.)--University of Hong Kong, 1997. / Includes special report entitled :Water and architecture. Includes bibliographical references.

This dissertation includes two fluid dynamics studies that involve fluid flows on vastly different scales, and therefore vastly different physics. The first study is of bacterial swimming using a flagellum for propulsive motion. Because bacteria are only about 10 [micrometers] in length, they swim in a very low Reynolds number (10⁻⁴) world, which is described by the linear set of governing equations known as the Stokes equations, that are a simplified version of the Navier-Stokes equations. The second study is of harmonic generation from nonlinear effects in internal, ocean-like wave beams that reflect from boundaries in a density stratified fluid. Internal wave reflection is an important oceanic process and may help sustain ocean circulation and affect global weather patterns. Such ocean processes have typical Reynold's numbers of 10¹⁰ or more and are only described by the full, nonlinear Navier-Stokes equations. In the low Reynolds number study, I examine theories by Gray et al.(1956) and Lighthill (1975) that describe swimming microorganisms using a helical flagellum for propulsive motion. I determine the resistance matrix, which can fully describe the dynamics of a flagellum, for flagella with different geometries, defined by: filament radius a, helical radius R, helical pitch [lambda], and axial length L. I use laboratory experiments and numerical simulations conducted in collaboration with Dr. Hepeng Zhang. The experiments, conducted with assistance from a fellow graduate student Chih-Hung Chen, use macroscopic scale models of bacterial flagella in a bath of highly viscous silicone oil. Numerical simulations use the Regularized Stokeslet method, which approximates the Stokeslet representation of an immersed body in a low Reynolds number flow. My study covers a biologically relevant parameter regime: 1/10R < a < 1/25R, R < [lambda] < 20R, and 2R< L <40R. I determine the three elements of the resistance matrix by measuring propulsive force and torque generated by a rotating, non-translating flagellum, and the drag force on a translating, non-rotating flagellum. I investigate the dependences of the resistance matrix elements on both the flagellum's axial length and its wavelength. The experimental and numerical results are in excellent agreement, but they compare poorly with the predictions of resistive force theory. The theory's neglect of hydrodynamic interactions is the source of the discrepancies in both the length dependence and wavelength dependence studies. I show that the experimental and simulation data scale as L/ln(L/r), a scaling analytically derived from slender body theory by my other collaborator Dr. Bin Liu. This logarithmic scaling is new and missing from the widely used resistive force theory. Dr. Zhang's work also includes a new parameterized version of resistive force theory. The second part of the dissertation is a study of harmonic generation by internal waves reflected from boundaries. I conduct laboratory experiments and two-dimensional numerical simulations of the Navier-Stokes equations to determine the value of the topographic slope that gives the most intense generation of second harmonic waves in the reflection process. The results from my experiments and simulations agree well but differ markedly from theoretical predictions by Thorpe (1987) and by Tabaei et al. (2005), except for nearly inviscid, weakly nonlinear flow. However, even for weakly nonlinear flow (where the dimensionless Dauxois-Young amplitude parameter value is only 0.01), I find that the ratio of the reflected wavenumber to the incoming wavenumber is very different from the prediction of weakly nonlinear theory. Further, I observe that for incident beams with a wide range of angles, frequencies, and intensities, the second harmonic beam produced in reflection has a maximum intensity when its width is the same as the width of the incident beam. This observation yields a prediction for the angle corresponding to the maximum in second harmonic intensity that is in excellent accord with my results from experiments and numerical simulations. / text