scholarly journals Analysis of the statistical variables related to the service in high performance male tennis in junior and absolute category

2019 ◽  
Vol 14 (42) ◽  
pp. 289-295
Keyword(s):  
High Performance ◽  
Decisive Role ◽  
Professional Status ◽  
Professional Category

The aim of the study was to show the differences in the game statistics related to the service in professional and junior category in three surfaces and to determine statistical differences during the game regarding both categories. A total of 269 individual Grand Slam tennis matches (Australian Open, Wimbledon and Roland Garros) were selected on three different surfaces (hard court, grass and clay). The data was collected from the official websites of the tournaments. A total of 10 variables were analyzed in professional category and 7 in junior. Absolute players obtained higher values (p <0.05) of aces, aces per set, percentage of 1st Services and points won with 1st and 2nd Service and committed fewer double faults per set than juniors in all surfaces. It is concluded that the increase in performance in the variables related to the service plays a decisive role in order to achieve a professional status.

scholarly journals A new high performance variable step size perturb-and-observe MPPT algorithm for photovoltaic system

2019 ◽  
Vol 10 (3) ◽  
pp. 1662
Author(s):  
Khadidja Saidi ◽  
Mountassar Maamoun ◽  
M’hamed Bounekhla
Keyword(s):  
High Performance ◽  
Decisive Role ◽  
Maximum Power ◽  
Photovoltaic System ◽  
Variable Step Size ◽  
Step Size ◽  
Rapid Variation ◽  
Point Tracking ◽  
Perturb And Observe ◽  
Power Point

The optimization of energy in a photovoltaic conversion chain remains a topic of study. The maximum power point tracking (MPPT) is considered the most appropriate solution to ensure the extraction of the maximum power which a photovoltaic generator can provide. Perturb and observe (P&amp;O) algorithm is the well-known MPPT tracker; it shows an important and decisive role in the development of photovoltaic (PV) systems. In This article we introduce a new improved adjustable step size P&amp;O (imVS_PO) MPPT method.The performances of the new algorithm are compared to the conventional P&amp;O MPPT techniques and to the existing adjustable step size P&amp;O (VS_PO) MPPT algorithm. The results clearly show the efficiency of the improved algorithm which contributed to the increase of the tracking speed with negligible fluctuations when the MPP is reached, and especially in rapid variation of insolation.

scholarly journals Fundamentals of beach volleyball blocking actions

2021 ◽  
Vol 15 (2) ◽  
pp. 90-100
Author(s):  
Gabriel Alexandru PETROVICI ◽  
◽  
Sorin ȘIMON ◽  
Keyword(s):  
High Performance ◽  
Decisive Role ◽  
Critical Elements

Beach volleyball is spectacular with many rapid actions, agility moves, and high jumping. One of the key elements present in high-performance beach volleyball, having a decisive role in the defensive apparatus, is the blocking movements. This action is done mainly by the tallest player or with the most considerable jumping ability. A high blocking ability can facilitate the defensive movement of the player that is positioned in the back of the court. Blocking ability is facilitated by anticipation capacity, good sight, agility movement, and high jumping ability generated by solid legs. This paper analyses the fundamentals of blocking actions in beach volleyball, giving critical elements in executing a good and efficient block.

scholarly journals Selection of Sport- and Racehorses

2005 ◽  
pp. 3-10
Author(s):  
Sándor Mihók
Keyword(s):  
High Performance ◽  
Decisive Role ◽  
Active Role ◽  
The Body ◽  
Second Phase ◽  
Human Needs ◽  
Equestrian Sports ◽  
The Moment ◽  
Selection Of

The utilisation of the horse has changed from time to time in response to human needs. For a few decades, it has been serving in several equestrian sports more intensively. It has also been proved that the standards for this kind of performance cannot be established in the way certain characteristics, such as the weight gain or milk production of other animal breeds can. Breeding horses for sporting comprises highly complex selection criteria.Some of these (e.g. external features, temperament, manageability and intelligence) do not put the breeder in a difficult position, but finding the traits that establishes the safety of sporting achievements poses a genetic problem.The performance of a horse for sports is a highly complex feature, which cannot easily be assessed or put down in figures. In addition, man plays a decisive role in shaping all kinds of performance of a horse at any given time by not only creating conditions for a better performance, but also by playing an active role in increasing it.The performance of the horse is mostly defined by its general aptitude to movement, ie., the regularity, clear rhythm and springiness of basic types of strides, as well as the ability to move in a naturally balanced way. Training and riding principles are based on these traits. These two together will determine about 70% of the value of the horse and its adequacy for high performance equestrian sports. In order to avoid subjectivity in determining the above variables and to increase the degree of objectivity, competent expert teams (trainers, judges, other riders) are employed to form an opinion on an individual animal.Assessing horse performance outside races does not seem to be efficient, as owing to the dominant effects of the environment, the indicator of inheritability is hardly above 0.1.Free jumping is an especially appropriate means for assessing a horse’s readiness and ability to move in an environment free of disturbing factors. In free jumping, it is especially important to judge the style of the jump. The first phase of jumping – as a sequence of movements – lasts from the moment the fore-feet touch the ground until the moment the hind-feet push off, while the second phase lasts from this moment until touching the ground. The most important task in the first phase is to make the angle of the dip of the body by the supporting fore-feet that is necessary for the jump. The quality of the jump is determined by the jumping and adequately expanded hind-legs. The intensity of pushing off and jumping done by the hind-legs can be inferred, and differences between individuals can be discerned from the shaping of the curve by the hocks and the paths of the pasterns in relation to the withers.

Well-Defined Materials for High-Performance Chromatographic Separation

2019 ◽  
Vol 12 (1) ◽  
pp. 451-473 ◽  
Author(s):  
Yu Liang ◽  
Lihua Zhang ◽  
Yukui Zhang
Keyword(s):  
Stationary Phase ◽  
Chromatographic Separation ◽  
High Performance ◽  
Chemical Engineering ◽  
High Efficiency ◽  
Decisive Role ◽  
Future Research ◽  
Separation Performance ◽  
Transfer Resistance ◽  
Materials Used

Chromatographic separation has been widely applied in various fields, such as chemical engineering, precision medicine, energy, and biology. Because chromatographic separation is based on differential partitioning between the mobile phase and stationary phase and affected by band dispersion and mass transfer resistance from these two phases, the materials used as the stationary phase play a decisive role in separation performance. In this review, we discuss the design of separation materials to achieve the separation with high efficiency and high resolution and highlight the well-defined materials with uniform pore structure and unique properties. The achievements, recent developments, challenges, and future trends of such materials are discussed. Furthermore, the surface functionalization of separation ma-terials for further improvement of separation performance is reviewed. Finally, future research directions and the challenges of chromatographic separation are presented.

scholarly journals Interphase Control in Lithium Metal Batteries Through Electrolyte Design

2021 ◽  
Author(s):  
Urbi Pal ◽  
Dmitrii Rakov ◽  
Bingyu Lu ◽  
Baharak Sayahpour ◽  
Fangfang Chen ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
High Voltage ◽  
High Performance ◽  
Elevated Temperatures ◽  
Coulombic Efficiency ◽  
Decisive Role ◽  
Cycling Performance ◽  
Lithium Metal ◽  
Ionic Liquid Electrolyte ◽  
Metal Anode

<p>Future rechargeable Li metal batteries (LMBs) require a rational electrolyte design to stabilize</p><p>the interfaces between the electrolyte and both the lithium metal anode and the high voltage</p><p>cathode. This remains the greatest challenge in achieving high cycling performance in</p><p>LMBs. We report an ether-aided ionic liquid electrolyte which offers superior Li metal</p><p>deposition, high voltage (5 V) stability and non-flammability. High performance cycling of</p><p>LiNi0.8Mn0.1Co0.1O2 (4.4 V) and LiNi0.6Mn0.2Co0.2O2 (4.3 V) cells is demonstrated with high</p><p>coulombic efficiency (>99.5%) at room temperature and elevated temperatures, even at high</p><p>practical areal capacity for the latter of 3.8 mAh/cm2 and with a capacity retention of 91% after</p><p>100 cycles. The ether-ionic liquid chemistry enables desirable plated Li microstructures with</p><p>high packing density, minimal ‘dead’ or inactive lithium formation and dendrite-free long-term</p><p>cycling. Along with XPS studies of cycled electrode surfaces, we use molecular dynamics</p><p>simulations to demonstrate that changes to the electrolyte interfacial chemistry upon addition</p><p>of DME plays a decisive role in the formation of a compact stable SEI.</p>

scholarly journals Interphase Control in Lithium Metal Batteries Through Electrolyte Design

2021 ◽  
Author(s):  
Urbi Pal ◽  
Dmitrii Rakov ◽  
Bingyu Lu ◽  
Baharak Sayahpour ◽  
Fangfang Chen ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
High Voltage ◽  
High Performance ◽  
Elevated Temperatures ◽  
Coulombic Efficiency ◽  
Decisive Role ◽  
Cycling Performance ◽  
Lithium Metal ◽  
Ionic Liquid Electrolyte ◽  
Metal Anode

<p>Future rechargeable Li metal batteries (LMBs) require a rational electrolyte design to stabilize</p><p>the interfaces between the electrolyte and both the lithium metal anode and the high voltage</p><p>cathode. This remains the greatest challenge in achieving high cycling performance in</p><p>LMBs. We report an ether-aided ionic liquid electrolyte which offers superior Li metal</p><p>deposition, high voltage (5 V) stability and non-flammability. High performance cycling of</p><p>LiNi0.8Mn0.1Co0.1O2 (4.4 V) and LiNi0.6Mn0.2Co0.2O2 (4.3 V) cells is demonstrated with high</p><p>coulombic efficiency (>99.5%) at room temperature and elevated temperatures, even at high</p><p>practical areal capacity for the latter of 3.8 mAh/cm2 and with a capacity retention of 91% after</p><p>100 cycles. The ether-ionic liquid chemistry enables desirable plated Li microstructures with</p><p>high packing density, minimal ‘dead’ or inactive lithium formation and dendrite-free long-term</p><p>cycling. Along with XPS studies of cycled electrode surfaces, we use molecular dynamics</p><p>simulations to demonstrate that changes to the electrolyte interfacial chemistry upon addition</p><p>of DME plays a decisive role in the formation of a compact stable SEI.</p>

scholarly journals Intercultural Management in Educational Organizations

2020 ◽  
Vol 29 (2) ◽  
pp. 163-172
Author(s):  
Olga Boyko ◽  
Rymma Mylenkova ◽  
Larysa Otroschenko
Keyword(s):  
High Performance ◽  
Decisive Role ◽  
Scientific Activity ◽  
Management Support ◽  
Educational Organizations ◽  
Educational Management ◽  
Higher Education System ◽  
Intercultural Management ◽  
Successful Communication ◽  
Global Labor Market

Human capital is an outstanding factor in any country’s competitiveness. This fact affirms the decisive role of education in the raise of a country’s economic and social prosperity in the international space. Reforming of domestic higher education system is carried out in the direction of new educational management support, universities management, scientific activity financing and intercultural interaction of universities with personalities, cultures and business. In that con­text most of the educational organizations become multicultural and multi­national ones. That is why universities as intercultural spaces are the focus of this paper. Contemporary universities face many challenges including the tasks of remaining intellectually and culturally viable in a fast changing world, pre­paring students to compete in the global labor market and interact with people from other ethnic, religious, cultural, national and geographic groups. Different approaches to the concept of “intercultural management in educational organi­zations” have been defined and its improvement resources in the higher edu­cation system have been identified. Taking into consideration that intercultural management is comprised of intercultural competences, the notion “intercul­tural competence” has been thoroughly analyzed. It was concluded that intercul­tural management, based on different dimensions of knowledge, attitudes, abili­ties and skills, is generally defined as the capability of successful communication and high performance of an organization in collaboration with other cultures.

A High Performance Energy Analyzer for Use in Electron Scanning Microscopy

1969 ◽  
Vol 27 ◽  
pp. 14-15
Author(s):  
A. V. Crewe ◽  
M. Isaacson ◽  
D. Johnson
Keyword(s):  
High Performance ◽  
Vertical Plane ◽  
Median Plane ◽  
Electron Gun ◽  
Uniform Field ◽  
Loss Mechanism ◽  
Electron Scanning Microscopy ◽  
Sector Type ◽  
Double Focusing ◽  
Electron Energy Loss

A double focusing magnetic spectrometer has been constructed for use with a field emission electron gun scanning microscope in order to study the electron energy loss mechanism in thin specimens. It is of the uniform field sector type with curved pole pieces. The shape of the pole pieces is determined by requiring that all particles be focused to a point at the image slit (point 1). The resultant shape gives perfect focusing in the median plane (Fig. 1) and first order focusing in the vertical plane (Fig. 2).

Vacuum System to Minimize the Specimen Contamination of High-Performance EM

1977 ◽  
Vol 35 ◽  
pp. 68-69
Author(s):  
N. Yoshimura ◽  
K. Shirota ◽  
T. Etoh
Keyword(s):  
Electron Microscope ◽  
High Speed ◽  
High Performance ◽  
High Vacuum ◽  
Vacuum System ◽  
Pump System ◽  
Pumping System ◽  
Diffusion Pump ◽  
Almost All ◽  
Cascade Type

One of the most important requirements for a high-performance EM, especially an analytical EM using a fine beam probe, is to prevent specimen contamination by providing a clean high vacuum in the vicinity of the specimen. However, in almost all commercial EMs, the pressure in the vicinity of the specimen under observation is usually more than ten times higher than the pressure measured at the punping line. The EM column inevitably requires the use of greased Viton O-rings for fine movement, and specimens and films need to be exchanged frequently and several attachments may also be exchanged. For these reasons, a high speed pumping system, as well as a clean vacuum system, is now required. A newly developed electron microscope, the JEM-100CX features clean high vacuum in the vicinity of the specimen, realized by the use of a CASCADE type diffusion pump system which has been essentially improved over its predeces- sorD employed on the JEM-100C.

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