977 resultados para Industries, Location of


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The problem of dimensional defects in aluminum die-castings is widespread throughout the foundry industry and their detection is of paramount importance in maintaining product quality. Due to the unpredictable factory environment and metallic with highly reflective nature, it is extremely hard to estimate true dimensionality of these metallic parts, autonomously. Some existing vision systems are capable of estimating depth to high accuracy, however are very much hardware dependent, involving the use of light and laser pattern projectors, integrated into vision systems or laser scanners. However, due to the reflective nature of these metallic parts and variable factory environments, the aforementioned vision systems tend to exhibit unpromising performance. Moreover, hardware dependency makes these systems cumbersome and costly. In this work, we propose a novel robust 3D reconstruction algorithm capable of reconstructing dimensionally accurate 3D depth models of the aluminum die-castings. The developed system is very simple and cost effective as it consists of only a pair of stereo cameras and a defused fluorescent light. The proposed vision system is capable of estimating surface depths within the accuracy of 0.5mm. In addition, the system is invariant to illuminative variations as well as orientation and location of the objects on the input image space, making the developed system highly robust. Due to its hardware simplicity and robustness, it can be implemented in different factory environments without a significant change in the setup. The proposed system is a major part of quality inspection system for the automotive manufacturing industry.

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In this paper, an algorithm for approximating the path of a moving autonomous mobile sensor with an unknown position location using Received Signal Strength (RSS) measurements is proposed. Using a Least Squares (LS) estimation method as an input, a Maximum-Likelihood (ML) approach is used to determine the location of the unknown mobile sensor. For the mobile sensor case, as the sensor changes position the characteristics of the RSS measurements also change; therefore the proposed method adapts the RSS measurement model by dynamically changing the pass loss value alpha to aid in position estimation. Secondly, a Recursive Least-Squares (RLS) algorithm is used to estimate the path of a moving mobile sensor using the Maximum-Likelihood position estimation as an input. The performance of the proposed algorithm is evaluated via simulation and it is shown that this method can accurately determine the position of the mobile sensor, and can efficiently track the position of the mobile sensor during motion.

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Hydroforming is one option to reduce vehicle weight while increasing component stiffness and rigidity. This typically involves using a fluid to form a component with high internal pressure. Tube hydroforming has gained increasing interest in the automotive and aerospace industries because of its many advantages such as part consolidation, good quality of the formed part etc. The main advantage is that the uniform pressure can be transferred to whole part at the same time. In low pressure hydroforming, the internal pressure is significantly and the hydroformed section length of line stays almost the same as the circumference of the blank tube. This paper details the comparison between high and low pressure hydroforming. It is shown that the internal pressure and holding force required for low pressure hydroforming process is much less than that of high pressure. Also stress and thickness distribution are more uniform and the process is highly suitable for the forming of advanced high strength steels.

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Oleocanthal is an olive oil phenolic possessing anti-inflammatory activity. Anecdotal evidence suggests that oleocanthal elicits a stinging sensation felt only at the back of the throat (oropharynx). Due to this compound possessing potentially health-benefiting properties, investigation into the sensory aspects of oleocanthal is warranted to aid in future research. The important link between the perceptual aspects of oleocanthal and health benefits is the notion that variation in sensitivity to oleocanthal irritation may relate to potential differences in sensitivity to the pharmacologic action of this compound. The current study assessed the unique irritant attributes of oleocanthal including its location of irritation, temporal profile, and individual differences in the perceived irritation. We show that the irritation elicited by oleocanthal was localized to the oropharynx (P < 0.001) with little or no irritation in the anterior oral cavity. Peak irritation was perceived 15 s postexposure and lasted over 180 s. Oleocanthal irritation was more variable among individuals compared with the irritation elicited by CO2 and the sweetness of sucrose. There was no correlation between intensity ratings of oleocanthal and CO2 and oleocanthal and sucrose (r = –0.15, n = 50, P = 0.92 and r = 0.17, n = 84, P = 0.12, respectively), suggesting that independent mechanisms underlie the irritation of CO2 and oleocanthal. The unusual spatial localization and independence of acid (CO2) sensations suggest that distinct nociceptors for oleocanthal are located in the oropharyngeal region of the oral cavity.

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The properties of the nickel(II)/2-hydroxy-5-nonylacetophenone oxime (HNAPO), an active ingredient in LIX 84, extraction system were characterised in a micellar system. The extinction coefficient, λmax of HNAPO (316 nm) and the Ni2+ complex (387 nm) in a neutral micellar system, poly dispersed octa-ethyleneglycol mono-n-dodecyl ether (G12A8) were determined as 3100 and 3500 M−1 cm−1, respectively. HNAPO was found to have a neutral micellar phase and bulk aqueous phase pKa of 11.5 and 12.5, respectively. The extraction equilibrium constant, Kex, was determined to be 10−8.0, and the deviation from theory observed at high pH can be accounted for by consideration of the competition for nickel(II) ions by hydroxide ions and HNAPO. A micellar phase of octa-ethyleneglycol mono-n-dodecyl ether (C12E8) was determined to be an appropriate model of the free oil/water interface from the solubilised location of HNAPO. Utilising the interfacial probe, 4-heptadecyl-7-hydroxy coumarin (HHC) allowed the determination of the electrostatic surface potential of mixed micelles of G12A8 and sodium dodecyl sulphate (SDS) or dodecyl trimethyl ammonium chloride (DTAC). The electrostatic surface potential was a linear function of the number of additional surfactant monomers within the G12A8 micelle, for the concentration range studied. For G12A8/DTAC mixed micelles, the surface potential was given by +1.1 mV per DTAC molecule per micelle, and for G12A8/SDS mixed micelles the relationship was −1.4 mV per SDS molecule per micelle.

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Background : Despite limited evidence evaluating early postnatal discharge, length of hospital stay has declined dramatically in Australia since the 1980s. The recent rising birth rate in Victoria, Australia has increased pressure on hospital beds, and many services have responded by discharging women earlier than planned, often with little preparation during pregnancy. We aimed to explore the views of women and their partners regarding a number of theoretical postnatal care ‘packages’ that could provide an alternative approach to early postnatal care.

Methods : Eight focus groups and four interviews were held in rural and metropolitan Victoria in 2006 with participants who had experienced a mix of public and private maternity care. These included 8 pregnant women, 42 recent mothers and 2 male partners. All were fluent in English. Focus groups explored participants’ experiences and/or expectations of early postnatal care in hospital and at home and their views of alternative packages of postnatal care where location of care shifted from hospital to home and/or hotel. This paper describes the packages and explores and describes what ‘value’ women placed on the various components of care.

Findings : Overall, women expressed a preference for what they had experienced or expected, which may be explained by the ‘what is must be best’ phenomenon where women place value on the status quo. They generally did not respond favourably towards the alternative postnatal care packages, with concerns about any shorter length of hospital stay, especially for first time mothers. Women were concerned about the safety and wellbeing of their new baby and reported that they lacked confidence in their ability to care for their baby. The physical presence and availability of professional support was seen to alleviate these concerns, especially for first time mothers. Participants did not believe that increased domiciliary visits compensated for forgoing the perceived security and value of staying in hospital. Women generally valued staying in hospital for the length of time they felt they needed above all other factors.

Key conclusions and implications for practice : Women were concerned about shortened postnatal length of hospital stay and these concerns must be considered when changes are planned in maternity service provision. Any moves towards shorter postnatal length of stay must be comprehensively evaluated with consideration given to exploring consumer views and satisfaction. There is also a need for flexibility in postnatal care that acknowledges women's individual needs.

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The paper reports on some of the findings of an extensive study undertaken in Victoria as part of a national Science, ICT and Mathematics Education in Rural and Regional Australia (SiMERR) project. One of the significant findings of the study was the extent to which teachers in the schools where the study data were collected took responsibility for many aspects of their own professional development. This was not at the expense of, but rather was in addition to, their involvement in school- and region-based professional development activity. The study also identifies some of the challenges faced, mostly related to the location of their schools in a rural or regional setting.

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The doctrine of rights has become part of private law jurisprudence. In this article the application of the doctrine in two decisions dealing with surface support in mineral law is examined. It is argued that the decision of Kriegler J in Elektrisiteitsvoorsieningskommissie v Fourie, namely, that the right to surface support is an entitlement, is more correct than Anglo Operations Ltd v Sandhurst Estates (Pty) Ltd in which it was decided that the right to surface support is a competence. It is submitted that depending on the legal location of the entitlement in the relationship between owner and miner of land one may simply refer to either an owner's entitlement to surface support or a miner's entitlement to undertake opencast-cast mining.

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We investigated changes in the spatial organization of individuals within a population of endangered Southern Bell Frogs Litoria raniformis over an eight-month period. Our results identified strong temporal changes in both spatial organization and the apparent location of L. raniformis within the study site. Ripley's K Function analyses showed that the position of individuals relative to one another shifted from random immediately after the study site was flooded (p < 0.005), to strongly clustered at spatial scales between 0-1 500 m during the peak breeding period (p < 0.005). The majority of flooded areas were dry by April and May and individuals again became aggregated within the remaining waterbodies.

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Occurrence patterns of parasitic plants are constrained by the distribution of suitable hosts and movement patterns of seed vectors and, accordingly, represent a simplified system to study many aspects of spatial ecology and determinants of distribution. Previous work has focused on the aerially hemiparasitic mistletoes, and it is unclear whether root parasites are affected by similar factors. Here, we evaluate spatial patterns in the root parasitic Santalum lanceolatum in an arid shrubland in north-western New South Wales, central Australia. In this region, the principal host is a long-lived nitrogen fixing shrub Acacia tetragonophylla closely associated with ephemeral creek-lines. The location of 765 individuals of both species was mapped along a 250-m section of creek-line using a total survey station, and occurrence patterns of the root parasite related to host distribution and landscape context. We used Ripley's K-function and the O-ring statistic to determine whether the distribution of S. lanceolatum was random, aggregated or regular; the spatial scales at which these patterns occurred; and to quantify any spatial associations between the parasite and its host, A. tetragonophylla. While acacias were closely associated with the creek-line, S. lanceolatum plants were more tightly clustered, displaying significant clustering at two spatial scales (1.2 m and 8.8 m). We suggest that host quality may act as an important constraint, with only those acacias growing in or near the creek-line being physiologically capable of supporting a parasite to maturity. Insights gained from spatial analysis are used to guide ongoing research in this system, and highlight the utility of the O-ring statistic for understanding patterns of distribution affected by multiple processes operating at critical scales.

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A complete understanding of residential housing markets, particularly in relation to variations in house prices both within and between suburbs, continues to present challenges to property researchers and forecasters. Factors affecting changes in housing demand are not yet completely understood, and accordingly market changes cannot always be confidently predicted. Most urban cities contain precincts that have high or low house values at the same time, regardless of characteristics such as distance to the city centre, location of transport or topography. Exactly why these variations in suburb values occur is often unclear, although local residents are able to easily identify differences between the status of each suburb, especially when one area is clearly perceived as superior to another. Consequently, houses in premium suburbs are sold for substantially more than houses in other areas, primarily due to this perceived higher demand. An understanding of reasons behind varying levels of buyer demand has always been difficult to fully encapsulate in housing studies, even though clear links have been observed between housing affordability and the type of inhabitant that would live in a particular area. This study confirms that traditional economic indicators can not always observe the degree of purchaser and vendor willingness in the residential property market, as per the International Valuation Standards Committee definition of market value, and substantial consideration must also be given to characteristics of individual buyers and sellers within the marketplace. No longer can the focus be narrowly focussed just on endogenous factors such as interest rates and inflation levels.
Accordingly, this research draws the disciplines of demography and housing research closer together and looks to social indicators for an insight into the level of house prices. To establish this link, a two-stage process is adopted where social area analysis initially identifies the characteristics of suburbs within an urban area. This information is then used to examine variations in suburb values, resulting in a clearer understanding of the relationship between demographic variables and house prices. This research analysed changes in the value of established residential house prices in Melbourne, Australia as well as the relationship with social structure. The added dimension of time highlighted change, with data drawn from 1996 and 2001. The results confirmed the existence of strong linkages between social constructs and established house prices. Whilst acknowledging that the overall level of house values is influenced by external economic and political factors, differences between suburb values can be explained by demographic variables. The results confirm that increased emphasis must be placed upon demography when seeking to understand variations in residential property values between urban areas.

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Overuse disorders of tendons, or tendinopathies, present a challenge to sports physicians, surgeons, and other health care professionals dealing with athletes. The Achilles, patellar, and supraspinatus tendons are particularly vulnerable to injury and often difficult to manage successfully. Inflammation was believed central to the pathologic process, but histopathologic evidence has confirmed the failed healing response nature of these conditions. Excessive or inappropriate loading of the musculotendinous unit is believed to be central to the disease process, although the exact mechanism by which this occurs remains uncertain. Additionally, the location of the lesion (for example, the midtendon or osteotendinous junction) has become increasingly recognized as influencing both the pathologic process and subsequent management.

The mechanical, vascular, neural, and other theories that seek to explain the pathologic process are explored in this article. Recent developments in the nonoperative management of chronic tendon disorders are reviewed, as is the rationale for surgical intervention. Recent surgical advances, including minimally invasive tendon surgery, are reviewed. Potential future management strategies, such as stem cell therapy, growth factor treatment, and gene transfer, are also discussed.

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This thesis argues that one type of multinational entity – the multinational bank – poses particularly significant challenges to the international tax regime in terms of its current profit allocation rules. Multinational banks are a unique subset of multinational entities, and as a consequence of their unique traits, the traditional international tax regime foes not yield an optimal interjurisdictional allocation of taxing rights. The opportunity for tax minimisation, achievable because of the unique traits, and realised through exploitation of the traditional source and transfer pricing regime, results in a jurisdictional distribution of taxing rights which does not reflect economic reality. There are two distinct ways in which the traditional international tax regime fails to reflect economic activity. The first way that economic activity may not be reflected in the distribution of the taxing rights to income from multinational banking is through the application of traditional source rules. The traditional sources rules allocate income where transactions are completed rather than where the intermediation services are arranged. As a result of their unique commercial role as financial intermediaries, by separating intermediary economic activity from legal transactions with third parties, multinational banks may distort the true location of the activity giving rise to income. The second way in which the traditional tax regime may fail to reflect economic activity is through the traditional transfer pricing regime requiring related or internal transaction to be undertaken at an arm’s length price. The arm’s length pricing requirement is theoretically deficient in its failure to recognise the highly integrated nature of multinational banking. In practice, the arm’s length pricing requirement is also difficult, if not impossible, to apply to multinational banks because of the requirement of comparability. The difficulties associated with the current model have resulted in a subtle move by multinational banks towards global formulary apportionment. This thesis concludes that, for the international taxation of multinational banks, the current source regime should be replaced with a system that allocates profits for tax purposes on the basis of income source, with source determined using a unitary taxation or global formulary apportionment system. It is argued that global formulary apportionment is a theoretically superior model that provides both jurisdiction to tax and allocated profits on the basis of the economic activity that generates the income.

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Throughout the world, the increasing use of land for agriculture has been associated with extensive loss and fragmentation of natural habitats and, frequently, the degradation of remaining habitats. The effects of such habitat changes have been well studied for some faunal groups, but little is known of their consequences for bats. The aim of this study was to investigate the ecology and conservation of an assemblage of insectivorous bats in a rural landscape, with particular focus on their foraging and roosting requirements. This increased knowledge will, hopefully, assist the formulation of policy and management decisions to ensure the long-term survival of bats in these altered environments. The distribution and abundance of insectivorous bats in the Northern Plains of Victoria was investigated to determine the impacts of land-use change and to identify factors influencing the distribution of bats in rural landscapes. Thirteen species of insectivorous bats were recorded across the region by sampling at 184 sites. Two species were rare, but the remaining 11 species were widespread and occurred in all types of remnant wooded vegetation, ranging from large blocks (≥200 ha) to small isolated remnants (≤5 ha) and scattered trees in cleared farm paddocks. There was no significant difference between remnant types in the relative abundance of bat species, in species richness, or in the composition of bat assemblages at study sites. In a subsequent study, no difference in the activity levels of bats was found between remnants with different tree densities, ranging from densely-vegetated blocks to single paddock trees. However, sites in open paddocks devoid of trees differed significantly from all types of wooded remnants and had significantly lower levels of bat activity and a different species composition. In highly cleared and modified landscapes, all native vegetation has value to bats, even the smallest remnant, roadside and single paddock tree. Roost sites are a key habitat requirement for bats and may be a limiting resource in highly modified environments. Two species, the lesser long-eared bat Nyctophilus geoffroyi and Gould's wattled bat Chalinolobus gouldii, were investigated as a basis for understanding the capacity of bats to survive in agricultural landscapes. These species have different wing morphologies, which may be influential in how they use the landscape, and anecdotal evidence suggested differences in their roosting ecology. Roosting ecology was examined using radio-tracking to locate 376 roosts in two study areas with contrasting tree cover in northern Victoria. Both species were highly selective in the location of their roosts in the landscape, in roost-site selection and in roosting behaviour, and responded differently to differing levels of availability of roosts. The Barmah-Picola study area incorporated remnant vegetation in farmland and an adjacent extensive floodplain forest (Barmah forest). Male N. geojfroyi roosted predominantly within 3 km of their foraging areas in remnants in farmland. However, most female N. geoffroyi, and both sexes of C. gouldii, roosted in Barmah forest up to 12 km from their foraging areas in farmland remnants. These distances were greater than previously recorded for these species and further than predicted by wing morphology. In contrast, in the second study area (Naring) where only small remnants of wooded vegetation remain in farmland, individuals of both species moved significantly shorter distances between roost sites and foraging areas. There were marked inter- and intra-specific differences in the roosts selected. C. gouldii used similar types of roosts in both areas - predominantly dead spouts in large, live trees. N. geoffroyi used a broader range of roost types, especially in the farmland environment. Roosts were typically under bark and in fissures, with males in particular also using anthropogenic structures. A strong preference was shown by both sexes for roosts in dead trees, and entrance dimensions of roosts were consistently narrow (2.5 cm). In Barmah forest, maternity roosts used by N. geoffroyi were predominantly in narrow fissures in large-diameter, dead trees, while at Naring maternity roosts were also found under bark, in buildings, and in small-diameter, live and dead trees. The number of roost trees that are required for an individual or colony is influenced by the frequency with which bats move between roosts, the proportion of roosts that are re-used, the distance between consecutive roosts, and the size of roosting colonies. Both species roosted in small colonies and regularly shifted roost sites within a discrete roost area. These behavioural traits suggest that a high density of roost sites is required. There were marked differences in these aspects of behaviour between individuals roosting in Barmah forest and in the fragmented rural landscape. At Naring, N. geqffroyi remained in roosts for longer periods and moved greater distances between consecutive roosts than in Barmah forest. In contrast, C. gouldii used a smaller pool of roosts in the farmland environment by re-using roosts more frequently. Within Barmah forest, there is an extensive area of forest but the density of hollow-bearing trees is reduced due to timber harvesting and silvicultural practices. Individuals were selective in the location of their roosting areas, with both species selecting parts of the forest that contained higher densities of their preferred roost trees than was generally available in the forest. In contrast, in farmland at Naring, where there were small pockets of remnant vegetation with high densities of potential roost sites surrounded by cleared paddocks with few roosting opportunities, little selection was shown. This suggests that in Barmah forest the density of trees with potential roosts is lower than optimal, while in farmland roosting resources may be adequate in woodland remnants, but limiting at the landscape scale since more than 95% of the landscape now provides no roosting opportunities. Insectivorous bats appear to be less severely affected than some other faunal groups by habitat fragmentation and land-use change. A highly developed capacity for flight, the spatial scale at which they move and their ability to cross open areas means that they can regularly move among multiple landscape elements, rather than depend on single remnants for all their resources. In addition, bats forage and roost mainly at elevated levels in trees and so are less sensitive to degradation of wooded habitats at ground level. Although seemingly resilient to habitat fragmentation, insectivorous bats are fundamentally dependent on trees for roosting and foraging, and so are vulnerable to habitat loss and ongoing rural tree decline. Protection of the remaining large old trees and measures to ensure regeneration to provide ongoing replacement of hollow-bearing trees through time are critical to ensure the long-term conservation of bats in rural landscapes.

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The game of golf requires hitting a ball from a range of lies over a range of distances in environments that include many obstacles to be avoided. Each of these different golf shots arc designed to move the ball from the tee to the hole in the least number of strokes. However, the fundamental assumption that seems to underlie the coaching of golf, particularly to novice players, is that acquisition of an ideal basic golf swing is the most important outcome of coaching. Implicit in this view are three further assumptions. The first is that once this ideal basic golf swing is acquired by players, they are able to complete a game of golf in a competent manner even though this requires a range of different shots. The second is that there is a close correspondence between the quality of execution of any golf swing as judged in terms of this ideal swing, and the quality of outcome of the golf shot of which the swing is a part, as judged by where the ball comes to rest. The third assumption is that visual inspection of the golf swing by a coach can reveal inadequacies which can be remedied leading lo improved performance in the game of golf. The research reported in this thesis is an investigation of these assumptions. The rationale underlying coaching of golf was examined by reviewing the golf coaching literature (Chapter 1) and conducting a survey of professional golf coaches (Chapter 2). Results of the literature review and the survey indicated that the major emphasis of golf coaching of novices was on their acquiring what might be described as an ideal basic golf swing. This typically involved identifying components in sequence. Little emphasis was placed during this stage of coaching on what might be described as the complete action of a golf shot which involves hitting a ball to some target location. To examine the assumption that there was a close correspondence between the quality of execution of the golf swing and the quality of the outcome of a golf shot, two studies were conducted. In Chapter 3 the development of a 70-item checklist to be used to evaluate the quality of execution of a golf swing is reported. This checklist was based on a detailed behavioural analysis of the golf swing involving collaboration with relevant experts (i.e., golf coaches, biomechanist, kinesiologist), and information derived from a review of golf coaching materials. Development of the checklist was an iterative process in which earlier versions were used to evaluate sample golf swings, and problems identified during this lest process were used to improve the checklist. The final 70-item checklist comprised of a static component with three parts (left-hand grip; right-hand grip; stance) and a dynamic component with six parts (half backswing; full backswing; half downswing; ball contact; half followthrough; finish position). This version of the checklist was used in a study (reported in Chapter 4) of the relationship between the judged quality of execution of a golf swing and the outcome accuracy of a golf shot. Three groups of golfers with varying ability and experience were required to hit 50 balls with a 9-iron club to a target. Outcome accuracy for each shot was assessed in terms of the distance between the target and the resting location of the ball. Edited videotapes (showing only execution of the golf swing) of the five most, and five least accurate shots produced a sub-sample of these golfers (four professional players; four novice players) were subsequently viewed by three expert coaches. They independently rated using the checklist, the quality of execution of the 80 golf swings in random order without having information about the accuracy of any shot. As expected, the professional golfers completed more accurate golf shots than did the novices, and the golf swings completed by the professionals were rated more highly than those completed by the novices. However, for both groups of golfers the results indicated that there was no clear relationship between the rated quality of execution of golf swings and the outcome accuracy of the shots of which the swing were the initial part. Chapter 5 provides a summary and overview of the research reported in Chapter 1 to 4. It is argued that this research suggests a need for a change of emphasis in golf coaching away from consideration of the golf swing in isolation to consideration of the golf swing as part of a complete action. That is, the quality of execution of a golf swing should not be judged simply in relation to some ideal set of golf-swing components, but rather in relation to how well the completed swing (i.e., the golf shot) achieves the desired aim of propelling the ball from its present location to the target location.