Top PDF Efficiency analysis of the speed turns in the crawl stroke swimming.

Efficiency analysis of the speed turns in the crawl stroke swimming.

Efficiency analysis of the speed turns in the crawl stroke swimming.

Savchenko M.I., Novyzkiy V.Y. Eficien- cy analysis of the speed turns in the crawl stroke swimming. Contemporary approaches to improving technique of the speed in the crawl stroke swimming, namely roll-forward turn were considered in the paper. The performance eficiency is deined by the time covering 15 meter distance. The students of the sports mas- tering group aged 16–20 took part in the experiment. The video recordings of the Ukrainian, European and World Champi- onships and Delympic Games, and also chronometration during the department trainings served as the experimental data. The research showed that white improving the technical level of turns per- formance, the attention should be paid to the exact performance of all the elements of the turns.
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Speed fluctuation as a determination factor of energy cost in Butterfly stroke

Speed fluctuation as a determination factor of energy cost in Butterfly stroke

and bioenergetic (energy cost) characteristics of different swimming techniques have been published, only a few approaches combine these two domains. Alves et al. (1996) made an attempt to explore the links between the intra-cycle variation of the horizontal velocity of displacement (dV) and the energy cost (EC) of swimming in front crawl and in backstroke. In backstroke, the correlation between dV of the hip and the EC presented significant values at low velocities (r=0.78 at 1.1 m.s-1 and r=0.66 at 1.2 m.s-1). In front crawl the relationship was non-existent at all studied velocities (Alves et al. 1996).
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Swimming speed in men’s 100-m freestyle confirms the fairness of the Paralympic Classification System: a meta-analysis

Swimming speed in men’s 100-m freestyle confirms the fairness of the Paralympic Classification System: a meta-analysis

A comprehensive search of the literature was performed using PubMed, EMBASE, ISI Web of Knowledge, SPORTDiscus, Academic Search Premier, CINAHL for complete studies with titles in English, Portuguese or Spanish, between the database inception and October 31, 2017. The keywords used were “disabled persons” OR “disabled sport” OR “physical disability” AND swim- ming OR aquatic OR crawl OR freestyle AND perfor- mance OR biomechanics OR “swimming speed” OR “swim speed” OR velocity. Inclusion criteria were stud- ies focused on official swim races with male swimmers. Exclusion criteria were: (i) only official swim races, (ii) absence of data and / or incomplete data in the papers and (iii) multiple publications in which results were recycled (i.e. reported more than once), with only one of these studies included. Clean swimming speed is understood without start, turn and finish times (Daly et al., 1999).
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Bioenergetical and biomechanical characterisation of butterfly stroke

Bioenergetical and biomechanical characterisation of butterfly stroke

Increases of V promoted decreases of dV, allowing a much more continuous butterfly stroke. Therefore, the expeculations of Nigg (1983), Vilas-Boas (1996) and Barbosa et al. (2005a), as well as, the observations of Togashi and Nomura (1992) or Manley and Atha (1992) were confirmed. Higher swimming velocities revealed to be more stable in what concerns to dV. On the other hand, lower swimming velocities can promote high negative impulses, due to increasing time decelerating the swimmer’s body. This might also promote a percentual increase of the kinematical energy transferred to the water, instead of its use for propulsion. Consequently, it will induce a lower propulsive efficiency. Toussaint (1990) comparing competitive and triathlon swimmers, at front crawl, verified that propulsive efficiency was significantly lower in the triathletes. Probably, as it was observed with present data, triathlon swimmers could present a higher dV. Takagi et al. (2004) compared the dV of the hip of a group of breaststrokers eliminated in the preliminaries of the 9 th FINA World Swimming Championships with another who advanced to the semi-finals. The authors verified that the dV was significantly higher in the group of eliminated breaststrokers. Apparently, these results justified the assumptions that lower dV is an important biomechanical characteristic to achieve high swimming velocities and, therefore, high performances. The higher dV observed in slow swimming velocities are not related to maximal values of the intra-cyclic velocity obtained, but to a lower minimal intra-cyclic velocity adopted (Takagi et al., 2004). So, swimmers should give a major attention to actions leading to strong body decelerations.
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Biomechanics of Competitive Swimming Strokes

Biomechanics of Competitive Swimming Strokes

The comparison of cohort groups is done comparing mean values or analyzing the variation of some selected biomechanical variables between different competitive level sub-sample groups. For instance, compare expert versus non-expert swimmers, national level versus international/elite level swimmers or, world championships and Olympic Games finalists versus non-finalists. It is obvious that better competitive level is related to a higher swim velocity. On the other hand, higher swim velocity, from better swimmers, is achieved by an increasing stroke length than remain swimmers (Craig et al., 1985; Vilas-Boas, 1996; Leblanc et al., 2007; Seifert et al., 2007). Higher level swimmers also present a higher efficiency, which is expressed by a higher stroke index (Sánchez et al., 2002; Jesus et al., 2011). During high-standard competitions, world-ranked swimmers already maintain a high stroke length. Therefore their biomechanical strategy to increase the swim velocity is to increase as well the stroke rate (Jesus et al., 2011). At least one study attempted to compare the stroke cycle kinematics between World championships medalists versus remaining finalists. There were no significant differences in the stroke kinematics between medallists and non-medallists. As both cohort groups have a very small gap performance, differences between them might be explained by other variables (Jesus et al., 2011). There are also some limb’s kinematics differences according to competitive level. The elite swimmers posses a great strength and power to accelerate through the water. They present a limb’s kinematics making them able to apply it effectively. Plus, the same limb’s kinematics also aims to maintain a better body streamlining position to reduce drag force (Cappaert et al., 1996). For instance, comparing elite versus non-elite swimmers, participating in world championships and Olympic Games (Cappaert et al., 1996;): (i) the trunk angle is lower and there is a higher elbow extension during the finish phase of the pulling pattern for elite than for non-elite swimmers swimming Butterfly stroke; (ii) there is a higher body roll and a higher emphasis in the kicking for elite backstrokes than non-elite ones; (iii) in Breaststroke, timing between arm’s and leg’s actions is a key factor as non-elite swimmers sometimes achieve a null body velocity within a stroke cycle; (iv) a higher elbow position is required to achieve higher propulsion and a higher body roll in Front Crawl, as done by elite swimmers in comparison to non-elite. Few studies suggest that better competitive level swimmers also present a lower intra-cyclic variation of the body’s swimming velocity (Manley and Atha, 1996; Takagi et al., 2004). This seems consistent in Breaststroke but less obvious in remaining swim strokes and should be clear out in near future.
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The role of business intelligence in decision process modeling

The role of business intelligence in decision process modeling

Another challenge is multiple classii cations when the customer belongs to more than one category. h ere is the case of web mining.h e Internet is get- ting the primate as a new channel for the goods dis- tribution, product promotion, transaction manage- ment and coordination of business processes and it becomes a valuable and suitable source of data about customers. More information on management can be seen in (Draker, 2003). However, multiple formats of data and distributive nature of knowledge on the Web are the challenge for collecting, revealing, organizing and knowledge management in the way that is suitable for providing support to business decision making. More information on decision support system can be seen in (Kotsiantis, 2011).
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The Concept of Early Vascular Ageing – An Update in 2015

The Concept of Early Vascular Ageing – An Update in 2015

In Malmö, Sweden, we have examined elderly individuals (mean age: 71 years) and this has revealed that markers of glucose metabolism and dyslipidaemia (elevated triglycerides, low HDL cholesterol levels) as well as waist circumference (a marker of active abdominal fat tissue with inlammatory action) are signiicantly associated with arterial stifness (c–f PWV), but not LDL cholesterol, smoking, or cystatin C (a marker of impaired renal function) after adjustment for MAP and HR. 19 The indings therefore point to two

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Factors Affecting The Adoption Of Mhealth In Maternal Health Care In Nakuru Provincial General Hospital

Factors Affecting The Adoption Of Mhealth In Maternal Health Care In Nakuru Provincial General Hospital

of social commitments and values such as social justice and equity, which are stated in their constitutions, signed treaties and conventions. Ministries of health oversee the overall development of health systems using their governance function, which includes policy analysis and formulation, regulating service delivery between partners, developing norms and standards for quality assurance and ensuring the implementation of agreed upon policies and strategies. The importance of ICTs in development process was long recognized and access to ICTs has even been made one of the targets of the Millennium Development Goal No. 8 (MDG 8),which emphasizes the benefits of new technologies, especially ICTs in the fight against poverty [26]. In the implementation of mHealth, ICT is a key component therefore policies on penetration, adoption and utilization of ICT in the health sector play a key role in enhancing mHealth adoption. The telecommunications sector of some countries such as Ghana, Kenya, Nigeria and Senegal, are very dynamic. Yet, as shown in the introductory section, Africa as a whole continues to lag behind other regions of the world. This is primarily as a result of the high cost of services [27]. Based on a review conducted across 17 Sub-Saharan African countries, Calandroet. al. argue that the national objectives of achieving universal and affordable access to the full range of communications services have been undermined either by poor policies constraining market entry and the competitive allocation of available resources; weak institutional arrangements with a dearth of technical capacity and competencies; and, in some instances, regressive taxes on usage. Gillwald [28] argues that in addition to competition and open access regimes, effective regulation of other factors such as spectrum and interconnection and tariffs are required to stimulate market growth, improve access, and lower prices. This is because: many competitive markets with several players have experienced spectrum allocation problems high cost of services as a result of retrogressive tax on mobile communications despite having an open market with several operators such as Uganda and expensive leased lines generally available from incumbent operators which hare mostly unregulated contributed to the high cost of doing business and inhibited growth and employment opportunities [28].
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The Influence of Small Amounts of Aluminium on the Spheroidization of Cast Iron with Cerium Mischmetal

The Influence of Small Amounts of Aluminium on the Spheroidization of Cast Iron with Cerium Mischmetal

Introduction of aluminium in the quantity of either about 0.6% (the alloy from melt No. 1) or about 1.1% (the alloy from melt No. 2) leads to the arising of the ferrite-pearlite matrix containing the precipitates of free cementite despite the significant silicon content in the cast iron (see data in Table 4 and Figs 2 and 4). The cast iron from these two melts did not contain the regular nodular graphite precipitates. In both cases the shape of graphite precipitates, according to the Standard [15], can be classified as II, its distribution as B, magnitude as 6 (see Figs 1 and 3).
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Examining the Accumulated Oxygen Deficit Method in Front Crawl Swimming

Examining the Accumulated Oxygen Deficit Method in Front Crawl Swimming

The fi rst test included several exercise bouts. During this test the swimming speed of the subjects was kept constant by an elec- tronic pacer, with successive fl ashing lights, placed at the bot- tom of the pool (TAR. 1.1, GBK-electronics, Aveiro, Portugal). The subjects were instructed to follow the pacer light signal. Dis- tance of the two fi rst bouts was 350 m, and 400 m from the third bout on. Initial velocity was established according to the swim- mers ’ individual performance in the 400 m freestyle minus 5 increments of velocity. The increments were 10 % of the 400 m best performance velocity per each 400 m stage until exhaus- tion. No warm-up was performed before the start of the test and recovery between successive bouts was individualized. The sub- jects started each bout when their VO 2 presented two consecu- tive values within 2 ml · kg − 1 · min − 1 from that recorded before
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The modification process of AlSi21CuNi silumin and its effect on change of mechanical properties of the alloy

The modification process of AlSi21CuNi silumin and its effect on change of mechanical properties of the alloy

Considering mechanism of modification of these precipitations one should take into account that effect of modification of hypereutectic silumins depends on earlier transition to liquid phase of sparingly soluble crystals of primary silicon [1-3]. Tests performed by authors of the studies [4-10] enable utilization of modification treatments together with making use of a various micro additives in order to improve properties of hypereutectoid alloys.

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The influence of the arc plasma treatment on the structure and microhardness C120U carbon tool steel

The influence of the arc plasma treatment on the structure and microhardness C120U carbon tool steel

Carbon steel C120U grade is largely used on the tools for cutting, for dies and knives, for stamping and drawing tools, hobs, thread rolling tools and in many other applications due to her typical properties - high hardness, good toughness and compressive strength. The surface of the steel can be modified by using surface engineering's techniques. Remelting of the surface layer by the source of concentrated energy is promising technique to improve properties of the materials [1-6]. Laser or electron beam use to melting of the surface of tool steels aims to obtain a modified layer with increased microhardness and abrasion resistance [7,8]. The surface remelted layer has usually a finer and more homogenous structure than its original base material. The remelting with the arc plasma (TIG- tungsten inert gas or GTAW - gas tungsten arc welding) used as an economical and easily
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Contribution To The Study Of Reproduction Parameters Of The European Conger Eel Conger Conger Linnaeus 1758 From The Western Algerian Coasts Oran Bay Algeria

Contribution To The Study Of Reproduction Parameters Of The European Conger Eel Conger Conger Linnaeus 1758 From The Western Algerian Coasts Oran Bay Algeria

The females G.S.I. presents two peak, the first in early winter, in January 2012, (1.15 % ± 0.66 %) and the second in the late winter, in March 2011, (1.45 % ± 0.83 %), and reached the lowest value in autumn. However, the higher values of males G.S.I. were observed in winter, in February 2012 (1.77 % ± 0.52 %), and in spring in March 2011( 1.72 % ± 1.4 %) and April 2011 ( 1.86 % ± 0.88 %) and reached the lowest value in autumn and summer. Similar findings have been reported by Hood and al., (1988) and Sullivan et al., (2003) on Conger. oceanicus and C.conger, respectively. Nevertheless, Correia et al., (2009), showed that the G. S. I. was lowest in autumn and high during winter and spring seasons. This was probably due to mobilization of somatic energy for the development of ovaries. The decline of G.S.I. from April to December 2011in female and from May 2011 to January 2012 in male may be due to the migration of the broodstock. Indeed, the reproduction is carried out in deep water, south-east of Sardinia in the Mediterranean Sea. A spawning ground exists in the Sardinia channel at depths between 600 and, at least, 800 m in the Mediterranean Sea (Cau and Manconi, 1983). The females H.S.I. showed two pairs of peak, first in winter, in January 2012 (1.89 % ± 0.36 %) and March 2011 (1.80 % ± 0.51 %), and the second in summer, in July 2011 (1.75 % ± 0.78 %) and September 2011 (1.84 % ± 0.66 %). The summer peaks coincided with hepatic fats deposits due to intense feeding activity, probably because of the abundant food, useful for fish gonad maturation (Abi-Ayad et al., 2011). The peaks measured in January and March was correlated with the dynamic of G. S. I. these can be explained either by the action of liver (precursor synthesis products involved in
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Model of knowledge representation about materials in the form of a relational database for CAPCAST system

Model of knowledge representation about materials in the form of a relational database for CAPCAST system

is the customer who gives the technical specification of the prod- uct and it is the customer who has to decide whether he can or cannot accept the price dictated by the manufacturer. Based on these restrictions, it is now the manufacturer who must decide whether he is able to execute the order (within the deadline ap- pointed and using the available facilities) and what will be the price of the product as dictated by the cost of production. Improv- ing the procedure of production costs estimation should improve the contract negotiations and make them more efficient. On the other hand, estimating the cost of production involves, among others, also the need to determine the type of material and treat- ment. The manufacturer can choose what materials he will use for the product and at what price, providing he can check which
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Human Capital and the Recent Fall of Earnings Inequality in Brazil

Human Capital and the Recent Fall of Earnings Inequality in Brazil

where is a set of linear restrictions that transforms the unrestricted model (1) on restricted model (2). 8 In our case, the restriction implies that the age, trend and (orthogonal) time dummies are sufficient to explain the behavior of each estimated statistic order across cells and over time. Imposing the restrictions means estimating weighted least squares regressions on the grouped data, for each quantile and education group separately. This procedure will give us consistent estimates of . Under the null that the restrictions are valid, the minimized value follows a chi-square distribution with degrees of freedom equal to the number of restrictions. In order to construct the test statistics, we only have to sum up the weighted squared residuals, that is, the estimated percentiles minus the predicted values minus the orthogonal time dummies.
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The Effect 0f Warm-up on Tethered Front Crawl Swimming Forces

The Effect 0f Warm-up on Tethered Front Crawl Swimming Forces

Warm-up procedures before competition or training are intended to assure benefits to athlete’s performance (Atkinson et al., 2005; Burnley et al., 2002) Although there are few data available on physiological responses to the warm- up, these routines are well accepted and commonly used by athletes and their coaches (Bishop, 2003). For example, the mechanisms related to the raise of core and muscle temperature seem to be of great importance for the proposed effects of warming-up before physical activity (Asmussen and Boje, 1945). Temperature might improve performance by decreasing the viscous resistance of muscles and joints (Wright and Johns, 1961; Cavagna, 1993), increasing of nerve conduction rate and speeding of metabolic reactions, such as the muscle
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The quality of castings obtained during lost-wax and Replicast CS processes in aspect of ecology

The quality of castings obtained during lost-wax and Replicast CS processes in aspect of ecology

Haratym, Dok ł adno ć wymiarowa odlewów wykona- nych w procesie Replicast CS, Archiwum Odlewnictwa rocznik 3, nr 9, Katowice 2003.. Arendarski, Niepewno ć pomiarów, Oficyna Wydaw- nic[r]

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Fields of study and the earnings gap by race in Brazil

Fields of study and the earnings gap by race in Brazil

The detailed questionnaire of the Census provides individual information about education, age, gender, race, employment status, labor earnings and occupation in the main job, and place of residence, among many other variables. Based on the information about race, which is self-reported, the sample is divided into white and black workers, where individuals who reported themselves as black or colored are included in the latter group. Asian and indigenous are excluded. For individuals who completed tertiary education, the Census has information about their fields of study. However, the classification system in 2000 is not the same as that in 2010. The appendix A describes how codes from different Census years are matched in this paper. As also shown in the appendix, the detailed categories for fields of study are aggregated into 10 broader groups, which are used in most of the analysis presented here. The Census questionnaire also allows identifying whether an individual has a graduate degree, although the 2000 survey does not distinguish between master ’s and doctoral degrees. In both periods, fields of study refer to the individuals’ highest degrees.
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Evaluation of susceptibility of the ZRE1 alloy to hot cracking in conditions of forced strain

Evaluation of susceptibility of the ZRE1 alloy to hot cracking in conditions of forced strain

The nil strength temperature (NST) for the alloy was determined by testing cylindrical Ø 6 x 90 mm specimens on the Gleeble 3800 simulator. S-type thermocouples were pressure welded to the specimens, and then the specimens were fixed in the chamber by means of copper holders. Constant distance of 52.4 mm was kept between the holders. After evacuation of air, the chamber was filled with argon (to 0.14 hPa). Then, the 0.6 – 0.7 kN minimum pre-load was applied and was maintained until the end of experiment. The specimens were heated at the 20 o C/s rate to 400 o C, and then at the 1 o C/s rate. The NST was determined as the temperature at which the specimen lost its cohesion. The NST for the ZRE1 alloy in as-delivered state is 535 o C.
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Electronic Government In Democratic Public Service In One Door Integrated Permit Handling Services Agency In The City Of Samarinda

Electronic Government In Democratic Public Service In One Door Integrated Permit Handling Services Agency In The City Of Samarinda

As state institutions, it should be possible to present and make use of electronic government in the function of serving the community. The emphasis in information technology to avoid the digital gap in at least. The provision of better government services to residents, increase interaction with the business world and industry, through access to information for community empowerment, a more efficient government or management. The results of that is expected of a reduction in corruption, the increase in transparency, the increase in comfort, and rising income or reducing expenses. Based on the results of research. Electronic government in the context of the ability to look the ability to run the function of government electronic media and build partnerships with private not optimal it is marked with the need for the allocation of fund optimally and support to work jointly with private companies to more so handling equipment and support for the success of electronic government could be achieved. As an effort to harmonize the acceleration of the completion of work, the licensing of the city of Samarinda must be able to implement the interests of citizens as well as problems faced by. No service to stop because of the support of funding led to the ability to reform it weakened to find appropriate formulations to stiffness in public service is not of stagnation. According to results of the review Khidasseli in Sutedi (2010) that norms behavior officers public service providers (a code of conduct for public officials), who set about norms in an administrative authority: 1) The obligation to work in accordance with the rules of law and standards of conduct of relevance to its function, 2) The obligation to put themselves in a neutral of or free from the
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