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An Evaluation of Performance Enhancements to Particle Swarm Optimisation on Real-World Data
Swarm Computation is a relatively new optimisation paradigm. The basic premise is to model the collective behaviour of self-organised natural phenomena such as swarms, flocks and shoals, in order to solve optimisation problems. Particle Swarm Optimisation (PSO) is a type of swarm computation inspired by bird flocks or swarms of bees by modelling their collective social influence as they search for optimal solutions.
In many real-world applications of PSO, the algorithm is used as a data pre-processor for a neural network or similar post processing system, and is often extensively modified to suit the application. The thesis introduces techniques that allow unmodified PSO to be applied successfully to a range of problems, specifically three extensions to the basic PSO algorithm: solving optimisation problems by training a hyperspatial matrix, using a hierarchy of swarms to coordinate optimisation on several data sets simultaneously, and dynamic neighbourhood selection in swarms.
Rather than working directly with candidate solutions to an optimisation problem, the PSO algorithm is adapted to train a matrix of weights, to produce a solution to the problem from the inputs. The search space is abstracted from the problem data.
A single PSO swarm optimises a single data set and has difficulties where the data set comprises disjoint parts (such as time series data for different days). To address this problem, we introduce a hierarchy of swarms, where each child swarm optimises one section of the data set whose gbest particle is a member of the swarm above in the hierarchy. The parent swarm(s) coordinate their children and encourage more exploration of the solution space. We show that hierarchical swarms of this type perform better than single swarm PSO optimisers on the disjoint data sets used.
PSO relies on interaction between particles within a neighbourhood to find good solutions. In many PSO variants, possible interactions are arbitrary and fixed on initialisation. Our third contribution is a dynamic neighbourhood selection: particles can modify their neighbourhood, based on the success of the candidate neighbour particle. As PSO is intended to reflect the social interaction of agents, this change significantly increases the ability of the swarm to find optimal solutions. Applied to real-world medical and cosmological data, this modification is and shows improvements over standard PSO approaches with fixed neighbourhoods
SHOT PERFORMANCE USING ANCHORED LONG PUTTING CLUBS
The study purpose was to measure putting outcome performance when different length putters were used with an anchoring mechanism. 72 skilled golfers each executed a total of 60 putts using standard, belly and long putters from two distances. Putting mechanics were assessed using SAM PuttLab™. From 1.83 m (6 ft) participants holed 80.3% of putts with a standard length putter, dropping to 78.6% and 75.3% for belly and longhandled putters. At 3.66 m (12 ft) participants holed 51.7% of putts with a standard length putter, and 50.8% and 46.9% for belly and long-handled putters. Shot performance showed no significant differences between clubs. There were significant (
COMPARISON OF SWING PATTERNS FOR HIGH AND LOW HANDICAP GOLFERS
INTRODUCTION: The majority of research in golf to date has focused on both professional and elite level competitors (Hume at al., 2005). However, with only 7% of male golfers falling into the category 1 group and 53% falling into categories 3&4 (handicap 13- 24) (USGA, 2007), the research being conducted does not reflect today’s average golfer. The aim of the present study was to carry out a kinematic analysis of the golf swing for category 1 and category 3&4 golfers to examine variation in movement patterns between skill levels
STRENGTH, BALANCE, AND FLEXIBILITY CHARACTERISTICS OF GOLFERS OF A VARIETY OF HANDICAPS
This research aimed to examine golf drive performance measures and physical performance variables of balance, strength and flexibility, for a wide range of golfing handicap levels. A total of 26 healthy right-handed golfers volunteered to participate in this study (M=17, F=9, 18-50 years, 0-36 handicap). Testing included an assessment of strength (hand grip strength test), balance (3 point star balance test), flexibility (sit and reach and shoulder reach flexibility), and indoor drive shot ball launch characteristics (high speed ball launch monitor). Golfers in the low handicap group had significantly (p?0.05) greater balance, strength, left shoulder flexibility, and better shot performnce than high handicap golfers. This research presents a rationale for the inclusion of strength, balance and flexibility conditioning in golf training programs
LOWER LIMB COORDINATION DURING A LAND-CUT TASK FOLLOWING ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION AND REHABILITATION
This study compared the lower limb coordination of the previously injured leg of ACL injured participantsparticipants (ACLr, n=18), against their non-injured leg and a control (nACL, n=18) leg. The lower limb joint and segment couplings were calculated during maximal drop-jump land and unanticipated cutting task. Differences between the previously injured and nACL control leg were present in all but one of the lower limb joint and segment couplings. Differences between the previously injured and nACL control leg were present in the hip rotation - knee abduction adduction, and knee rotation knee abduction adduction couplings. The hip and thigh were the main areas where differences were reported. Altered proximal neuromuscular function may be the origin of these altered coordination patterns
HOW POLITICAL NEWS MOVES MARKETS
The United States’ position on trade and the Federal Open Market Committee's outlook both govern the pricing of equities, debt, and other derivatives domestically and internationally. Unprecedented executive influence on trade and the Fed, coupled with a president’s unpredictable and instantaneous communication on Twitter, inspired banks and trading firms to create indexes, bots, and derivatives to account for this phenomenon. This thesis asks the question: how do President Donald Trump's tweets affect the broader stock market in terms of pricing and volatility? I use intra-day event study analysis on a sample of 2148 President Donald Trump tweets to evaluate the market impact of general tweets. I segmented the tweets into Fed-related tweets, Trade-related tweets, and other tweets before evaluating the pricing and volatility impacts using the SPX index and VIX index respectively. I found significant differences between the market reaction to trade-related tweets and Fed-related tweets and other tweets.Bachelor of Business Administratio
MARATHON STRIDE RATE DYNAMICS: A CASE STUDY
The purpose of this study was to investigate stride rate (SR) dynamics of a recreational runner participating in his debut marathon. Tibial accelerometry data obtained during a half marathon (R1) and marathon (R2) were utilised. SR data were extracted utilising novel computational methods and descriptive statistics were utilised for analysis of R2, and comparison of the first half of the marathon (R2half) to R1. Results indicate that the participant employed comparable SR strategy in R1 and R2half. For R2 a combined decreasing trend in SR and increased variance in SR from 30 km (R2 =0.0238) was observed. Results indicate that the participant had the ability to maintain SR strategy for the first half of the marathon, however as fatigue onset occurred this ability decreased. Running strategies on SR during fatigue may be of future use to recreational runners
INFLUENCE OF ANKLE TAPING ON DYNAMIC BALANCE PERFORMANCE
This research aimed to investigate the effect of ankle taping on dynamic balance performance. Eighteen recreational athletes without any previous ankle sprain history performed six star excursion balance tests on each leg; randomly three trials with taped ankles and three trials without. A three-layer modified closed-basket inelastic taping technique was used. Normalised (by leg length) reaching distance was measured. It was found 1. Movement direction significantly influenced normalised reaching distance
(p0.05). Ankle taping did not affect dynamic balance performance therefore taping could be used without risk of negative impact on balance, and protect from ankle
sprain for sportspersons
COMPARISON OF ACCELEROMETRY STRIDE TIME CALCULATION METHODS
The purpose of this study was to investigate how a newly proposed method of stride time calculation, utilising data filtered at 2 Hz, compared to previous methods. Tibial accelerometry data for 6 participants completing half marathon running training were collected. One run was selected for each participant at random, from which five consecutive running strides were ascertained. Four calculation methods were employed to derive each stride time and results were compared. No significant difference was found between methods (p=1.00). The absolute difference in stride time, when comparing the proposed method to previous methods, ranged from 0.000 seconds to 0.039 seconds. Filtered data could offer a simplified technique for stride time output during running gait analysis, particularly when applied during automated data processing for large data sets
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