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This study aimed to examine the effects of age group (under-11, under-15, and under-23) on the external, internal workloads, and tactical individual actions when playing 4v2, 4v4, and 4v6 ball possession small-sided soccer games. Data were analysed separately under the opponent perspective (4vX) and by the cooperation perspective, according to teammates (4v2+X). For all opponent formats, statistical differences were found for walking, with older age groups covering longer distances. Higher running distances were found in 4v4 game format for U11s, while U23s reported higher RPE scores in 4v4 and 4v6 formats. More passes were performed in 4v2 and 4v4 game formats for U11s and a higher maximum passing speed in 4v6 format for U15s and U23s. In the cooperation perspective, statistical differences were found for all external workload variables: U11s covered more distances while sprinting, whereas U23s walked more, perceiving the task as more intense. Similarly, U11s performed a higher amount of tactical individual actions also in every format. Younger players seem to benefit from a lower level of opposition to mature tactical individual actions, while older players can develop fast ball circulation in numerical inferiority.

The goal of this study was investigation of milling process conditions on microstructural and features of an aluminium matrix nanocomposite reinforced with 10 wt. % Al3Mg2. For this, the initial po...

The article is dedicated to the problems of finishing of parts with spherical surfaces, including parts of flange cranes «Ball Cork». The classification of details with spherical surfaces, their areas of use and methods of spherical surfaces processing are discerned. An analysis of the industrial processing technologies of such details was carried out. It showed that the traditional methods of processing have a number of shortcomings, such as low productivity, high cost, difficulty to ensure accuracy, appearance of grinding burns, micro-cracks, directional tool tracks. The application of machining methods without rigid connection of the VPIZ system on finishing operations of spherical details processing with achievement of high indicators of accuracy and surfaces quality is offered. One of the wider methods of processing parts of a folding configuration without fixing is shown - a vibrating processing of parts in a bulk in the hard abrasives. The results of experimental measurements of spherical surfaces grinding and polishing of the parts with different sizes of the type «Ball Cork» of the valves of the shut-off valves are induced. Examples of technological processes design of vibration grinding and polishing and examples of their technological documentation registration are resulted. The positive effect of the application of vibration treatment in the environment of free abrasives for the treatment of spherical parts on the example of ball plugs of different sizes. It is established that after vibration grinding and polishing it is possible to improve the surfaces quality from the 3rd to the 8th roughness classes. On the basis of researches the scientifically substantiated practical recommendations concerning a choice of the equipment, the tool and processing modes of details «Ball Cork» on operations of vibration grinding and polishing are resulted. Installed, as a result of the variability and polishing of the surface from the 3rd to the 8th class of shorts. Practical recommendations for the selection of the possession, tool and mode of processing parts «Ball Cork» at the operations of the vibration process and polishing. Methods for increasing the productivity of technological processes of vibration grinding by reducing the processing time: by using as a tool of abrasive granules in the form of P12; carrying out vibration grinding on the machine with the possibility to change the position of the shaft-vibrator relative to the container and in the location of the container at an angle of 45° to the ordinate axis perpendicular to the longitudinal axis passing through the center of mass of the container.

The article considered the issue of assessing the risk of exploitation of spherical reservoirs with liquefied petroleum gases. The main hazards that can arise when storing liquefied petroleum gases such as ethane, ethylene, butene in ball tanks are briefly described. Analyzed the existing international standards for risk management, as well as Nakaz No. 637. A brief analysis of the causes of accidents on spherical reservoirs is carried out using literature sources. A plan for the location of spherical reservoirs on the ground is presented The principle of analysis of chemical-technological systems has been studied, and with the help of a fault tree, cause-and-effect relationships have been built in case of equipment failures and the probability of complete destruction of a spherical reservoir has been found. The article also contains an event tree showing scenarios and probabilities of accidents. In the event trees, the probabilities of various intermediate events are given: the probability of instant ignition of the fuel-air mixture, the probability of an accidental ignition source on the territory of the enterprise, the probability of triggering the water irrigation system installed on the ball tanks to prevent the effect of a fire on other equipment of the liquefied gases park. The calculation of the damaging factors arising in an emergency was carried out, an assessment was made of the areas of injury to personnel during explosions, the radii of burns during a strait fire and when a fireball occurs. The article presents the field of territorial risk during the operation of ethane ball tanks. In the figure, the zones of territorial risk are highlighted in different colors, reflecting the boundaries of the likelihood of the implementation of damaging factors at a certain point in the terrain. According to the zones of territorial risk, conclusions were drawn about the individual risk of human death in the zone of action of damaging factors. Based on the numerical values of the individual risk, a decision was made on the safety of the tank operation and on the sufficiency of the protection measures and control of operating parameters provided for by the project.

AIM: The study was conducted to evaluate maximum biting force (MBF) in two different attachment systems (bollard a vs. ball and socket attachment) retaining mandibular overdenture using a split-mouth design. SUBJECTS AND METHODS: Twelve completely edentulous patients received complete dentures and after adaption of the patient with the new denture, 24 implants were inserted in the canine region using two-stage surgical technique and conventional loading protocol. Six patients received the Bollard attachment at the right side and the Ball and Socket at the left side. Moreover, the other six patients received the bollard attachment at the left side and the ball and socket attachment at the right side. Each patient was treated according to split-mouth design. Insertion of each of the attachment type was assigned randomly. Using occlusal force meter instrument, MBF was measured immediately after loading (0), after 6 months (6), and after 12 months (12). RESULTS: Significant statistical differences (p < 0.05) were obvious in in MBF between Attachment (1) and Attachment (2) immediately after loading (0 months), after 6 months (6) and after 12 months (12) follow-up visits. CONCLUSION: Mandibular implant retained overdenture received Bollard abutment that retained with the denture by the help of resilient liner “Retention.sil”* without housing have higher biting forces than mandibular implant retained overdenture with ball abutment where the plastic house was picked up by monomer free self-cured acrylic resin.

The purpose of this study was to determine the agreement in peak ball speed measured using a radar gun and motion capture system then examine the influence of angular position. Peak ball speed was recorded with the radar gun in-line with the ball trajectory (0° offset) and at 5° offsets up to 35°. Agreement between devices was calculated at 0° and for grouped offset bins (0-5°, 10-15°, 20-25°, and 30-35°). At 0°, a strong correlation (

In this paper, a method is proposed for identification of 11 position-independent geometric errors (PIGEs) of five-axis machine tools with a tilting/rotary table via single-ball measurements and three-dimensional (3D) geometric sensitivity analysis. Eleven PIGEs were identified, including three squareness errors between three linear axes, two offset errors, and two squareness errors for the tilting/rotary axis. The approach uses a set-up of a ball and three circular measurements involving simultaneous control of two linear axes and a tilting/rotary axis. A 3D geometric sensitivity analysis is carried out to investigate the effects of the 11 PIGEs on each of the measurement’s paths and between the measurement paths. The particular measurement paths used allow the radius of the circular path at the first measurement, and the distance between the circular paths of the second and third measurements, to be increased for accurate identification of the 11 PIGEs. The proposed method was also used to derive root-sum-square values of sensitivity coefficients, and then applied to a commercial five-axis machine tool for experimental verification. It calculates the peak-to-valley values of the positional deviations in the x-, y-, and z-directions along the test paths as 152.1, 118.2, and 47.1 μm, respectively, without compensation for the identified PIGEs, and as 17.6, 15.0, and 11.4 μm, respectively, with compensation. The results confirm the validity of our proposed method.

Introduction. A soccer player with good ball control is the one who is able to perform complex coordinated situational motor actions in a certain space and in as short time period as possible. The analysis included variations in the angle of the knee joint of the leg receiving a ball (AKLR), angle of the knee joint of the supporting leg (AKLS), angle between thighs (ABT), trunk bending angle (TBA), hip joint point height (HPH), and ball distance after controlling the ball (BDAC) between effective and ineffective passing in soccer. Material and Methods. A total of 12 university soccer players (age: 20.8 ± .83 years old, experience: 4.7 ±.78 years) voluntarily participated in the study. The players made five attempts to control the ball with the inside foot. The best attempt was analysed for each case (effective and ineffective). Results. The degrees of AKLR, AKLS, ABT, TBA and HPH were significantly greater in effective passing than those in ineffective passing; the observed effect sizes were 4.87, 2.53, 1.77, 3.98, and 3.40, respectively. BDAC was meaningfully greater at ineffective passing (effect size: 2.03). Conclusions. There were significant differences in the values of kinematic variables used to test ball control by effective and ineffective passes (p < 0.05). The research sample, in terms of the values of kinematic variables, achieved noticeable progress during the performance of ball control for effective passing, which showed its effectiveness in reducing the distance after controlling the ball.

We demonstrate a prototype for a compact, hybrid daylight harvesting system that collects and transports sunlight to illuminate dark spaces, up to two levels underground. The prototype is designed to have a compact size so that it can be mounted on top of a conventional lamp post at ground level and the system serves an additional purpose of a streetlamp for ground level illumination during nighttime. The system utilizes an acrylic ball lens as solar concentrator, and the focused sunlight is directly coupled into a single plastic optical fiber that transports it to indoor spaces. The spherical symmetry of the ball lens allows it to be static, while the position of focused light spot varies gradually underneath it, in accordance with the solar position in the sky. Therefore, only the light-collecting optical fiber needs to be moved under the ball lens, obviating the need for heavy-duty motors typically used to align solar concentrators along the direction of sun’s rays. The focused sunlight under the ball is tracked using a microcontroller-based tracking mechanism. This design is the first demonstration of a daylight harvesting system, to the best of our knowledge, using a ball lens as static sunlight collector and a movable optical fiber tracking the focused spot underneath the ball. The moving parts in the proposed system are lightweight and are well concealed from environmental hazards like dust, wind and moisture.

Among the student ideas about forces discussed in the literature, perhaps the most commonly reported is the notion of an impetus force, or the “belief that there is a force inside a moving object that keeps it going and causes it to have some speed.” For example, Clement asked university students taking introductory mechanics to draw a free-body diagram for a coin that has been tossed upward. He found that students often drew an arrow in the direction of the coin’s motion, at a point midway between the initial toss and the turnaround point, sometimes providing reasoning that suggested that the arrow corresponds to a “force from your hand” or the “force of the throw.” Clement interpreted these responses as indicating that “student[s] may believe that continuing motion implies the presence of a continuing force in the same direction, as a necessary cause of the motion.” As another example, in a study conducted with undergraduate students at Johns Hopkins University, McCloskey, Caramazza, and Green asked students to draw the path a ball will follow after it exits the curved tubes pictured in Fig. 1. The authors found that students often drew curved trajectories for the ball exiting each tube, and they coined the term “curvilinear impetus principle” to describe students’ reasoning. They write that students reasoned as though “an object constrained to move in a curved path acquires a curvilinear impetus that causes it to continue in a curved trajectory for some time after the constraints on its motion are removed.”

The collision and wear caused by inevitable clearance in kinematic pair have an effect on the dynamic characteristics of the mechanism. Therefore, we established the dynamic model of a 3RSR (R is the revolute joint and S is the spherical joint) parallel mechanism with spherical joint clearance based on the modified Flores contact force model and the modified Coulomb friction model using Newton-Euler method. The standard quaternion was introduced in the constraint equation, and the four-order Runge-Kutta method was adopted to solve the 3RSR dynamic model. The simulation results were compared and analyzed with the numerical results. The geometrical parameters of the worn ball socket were solved based on the Archard wear model, and the geometrical reconstruction of the worn surface was carried out. The geometric reconstruction parameters were substituted into the dynamic model, which was to analyze the dynamic response of the 3RSR parallel mechanism with wear and spherical joint clearance. The simulation results show that the irregular wear occurs in the spherical joint with clearance under the presence of the impact and friction force. The long-term wear will increase the fluctuation of the contact force, thereby decreasing the movement stability of the mechanism.

Background: Football is one of the most popular sportsworldwide. Heading of the ball is an essential part of thegame. There is no much knowledge about the rule of lowerlimb muscles during the heading of the ball.Aim of Study: To examine actions of quadriceps, tibialisanterior, hamstrings, and calf muscles during the heading ofthe ball by using electromyography.Material and Methods: The actions of quadriceps, tibialisanterior, hamstrings, and calf muscles are studied by electro-myography in 15 young professional soccer players fromdifferent positions. The players headed the ball forwardlyfrom four different positions: Standing still; jumping; runningforward; running and jumping forward.Results: We found that all examined lower limb muscleswere active during the heading of the ball especially thetibialis anterior which produced more significant strengththan all other examined muscles in all different positions ofthe heading of the ball.Conclusion: This study suggests that healthy well trainedlower limb muscles especially the tibialis anterior may beessential for the accurate and effective heading of the ball inprofessional soccer players. In addition, professional playersshould avoid heading of the ball when lower limb musclesare injured especially tibialis anterior.

The purpose of this study is the application of the cooperative learning model in order to improve the learning outcomes of big ball games in class III students of SDN 1 Landasan Ulin Tengah Banjarbaru. The method used in this study is a classroom action research method, namely the researcher as an observer. Observations at the time the teaching and learning process takes place. The subjects of this study were 27 students of class III (three) at SD Negeri 1 Landasan Uling Tengah Banjarbaru for the 2019/2020 academic year, consisting of 16 boys and 11 girls. The process of increasing the ability of learning outcomes in the manipulative motion material of big ball games by emphasizing the cooperative learning model, getting good results based on the predetermined KKM, which is 75. Defined results through cooperative learning model can improve student learning outcomes in motion manipulative big ball game with the following average: Observation of the first meeting was an average value of 70.1 The number of students who reached KKM 75 was 9 students with a percentage of 33.33% and the number of students who did not reach the KKM was 18 students with a percentage of 66.67% . and at the second meeting the average value was 85.5, the number of students who reached KKM 75 was 27 students with a percentage of 100% and the number of students who did not reach the KKM was 0 students with a percentage of 0% so this research was stopped at the second meeting (II).

Achieving a unique solution for the 3D inverse design of a curved duct is a challenging problem in aerodynamic design. The centre-line curvature, and cross-sections’ area and shape of a 3D curved d...

There are a number of techniques available for characterising powder flow behaviour, most of which are carried out under quasi-static conditions. Quasi-static methods are commonly used to define the conditions for the flow initiation, but they are inadequate for characterising the shear strain rate sensitivity of powder flow. The number of devices available to capture powder behaviour under dynamic conditions is indeed very limited. The very few commercially available instruments all require a large sample, which is not desirable for early stages of product development. We have recently proposed the use of ball indentation for characterising flow resistance of cohesive powders. The technique can be applied at very low consolidation stress levels (much less than 1 kPa) and requires only a small sample quantity, typically a few mm3. Previous work showed a good correlation of flowability with established methods under quasi-static conditions. Therefore, an attempt is made to extend the method to dynamic conditions and investigate the sensitivity of the stresses on the shear strain rate for a range of powders, including glass ballotini, α-lactose monohydrate, calcium carbonate (Durcal) and limestone. The results show the existence of a threshold boundary above which the flow resistance experienced by the penetrating ball becomes dependent on the shear strain rate. This is in line with the trends reported in the literature. Therefore, the ball indentation technique has the potential to be used to assess powder flowability at high strain rates.

The special features of thick combined electrospark coatings (СESC) formed on cylindrical 12Kh18N10T stainless steel samples are analyzed. The samples were carbonized with the help of combined electrospark alloying (CЕSA) using an Elitron-52A device and aluminized with the help of electrospark alloying (ESA) using an EIL-9 automated device at a discharge energy of Wd = 3.4 J. The coatings were deposited on the aluminized surfaces with the help of the T15K6 hard alloy using the same device at Wd = 0.9 and 3.4 J. The СESC roughness was reduced by means of ball rolling and applying a metal–polymer material (MPM) reinforced with the VK6 hard-alloy powder. A new technology to recover parts, such as rotation bodies, has been proposed for practical applications. It made it possible to form the СESC on 12Kh18N10T steel in the following sequence: CЕSA → ESA Al → ESA T15K6 → MPM (reinforced with VK6), with a thickness up to 1.5 mm, a continuity of 100%, a microhardness of ∼10 100–9500 MPa, and a roughness of Ra = 1.2 μm.

Viscosity is the one of the major parameters to be considered in fluid related experiments and also in many industries. A new method of calculation of Dynamic Viscosity using the Viscometer which is easy for experimentation, with less calculation efforts, simple in design, construction with min. investment and no or minimum maintenance. This Paper intends to find the viscosity of Opaque fluids using falling ball viscometer. Falling Ball Viscometer works with Strokes law as the correction factor is multiplied in the calculation. As the correction factor is derived from the outcomes from the experiment and C-Code was written to make the calculation more efficient.

General Court, T–368/20, Smiley Miley, Inc. v European Union Intellectual Property Office (EUIPO), EU:T:2021:372 The article analyses the decision in Smiley Miley v EUIPO, in which the General Court held that the American singer-songwriter and actress Miley Cyrus was entitled to use her name as a trade mark. It considers the importance of this ruling in relation to the protection afforded to public figures of international recognition through trade marks in the EU.

There is defined a total basing error arising during centerless ball grinding using driving disk helical grooves with different forms. On the basis of computations there is offered a design of a driving disk with the trapezoidal helical groove. A design of a supporting knife which allows carrying out efficiently an automatic position correction of the measuring base of operation size during ball grinding is offered.

In present paper we show results of ball-on-disk wear experiment of MoS2 film deposited on Ti6Al4V substrate. The ball materials is aluminum oxide. The tests are performed for different surrounding temperature conditions: 20 oC, 200 oC and 350 oC. It is shown that depth of the wear groove increases with increasing surrounding temperature. A finite element modeling approach is next developed to mimic the experimental observations of ball-on-disk wear process. It is based on the assumption of steady state condition developed during short time scale at contact region. The steady state results can next be applied to long time scale in which wear process is numerically simulated. Model results are compared with experimentally obtained wear groove and show satisfactory agreement.

Objectives: Upper limb explosive power is an important motor quality for sporting performance and indicates use of anaerobic energy systems. The Wingate Anaerobic Test (WAnT) has been considered to be a valid and reliable tool for the assessment of anaerobic power and functional performance of elite athletes. However, it is expensive and a lab based test and requires skilled manpower. The seated medicine ball throw test (SMBT) is inexpensive, easy to assess and since equipment required is minimal, it can be easily used as a field test. Hence, the purpose of the study was to determine if the SMBT method could be used as an alternative for WAnT test so that a reliable and inexpensive test is available for athlete monitoring and talent identification screening. Materials and Methods: Male elite athletes aged 18–30 years (n = 100), who were involved in national level competition of three sports discipline, namely, Boxing (n = 34), Wrestling Greco-Roman (GR) (n = 36), and Wrestling Freestyle (FS) (n = 30), were tested on crank-arm ergometer for WAnT and SMBT to measure an peak power or explosive power for the upper body. Results: SMBT test results were significantly positively correlated with upper body peak power measured by WAnT in all sportsmen (r = 0.55, P = 0.0002). One sample t-test results showed that the mean difference between SMBT and peak power is close to zero among Boxers (P = 0.13) and FS wrestlers (P = 0.89) and GR Wrestlers (P = 0.49). Overall, 97% pairs of SMBT and peak power were within the limits of agreement among all sportsmen, showing that results using both the tests were agreeable. Conclusion: This study suggests that SMBT tests could be used as an alternative field test to measure anaerobic power in Wrestlers, Boxers, and sports where the involvement of upper body muscles take place predominantly. In addition, the SMBT protocol used in this study provides an easy way for the coaches to assess the athletes on the field during talent identification and also to evaluate their training program.

Wong, R, Laudner, K, Evans, D, Miller, L, Blank, T, and Meister, K. Relationships between clinically measured upper-extremity physical characteristics and ball spin rate in professional baseball pitchers. J Strength Cond Res 35(5): 1331-1337, 2021-During baseball pitching, physical characteristics of the shoulder, elbow, wrist, hand, and fingers have been hypothesized to be critical to creating ball spin. The purpose of this study was to determine if pitchers with greater shoulder, elbow, wrist, and finger range of motion (ROM), arm and hand length, wrist strength, or grip and finger strength would produce greater ball spin than those with less physical characteristics. Ninety, asymptomatic, professional baseball pitchers participated (age = 24.5 ± 3.9 years; height = 189.9 ± 6.1 cm; body mass = 92.6 ± 10.6 kg). Goniometers and a digital level were used to measure shoulder, elbow, wrist, and finger ROM, a tape measure was used to assess arm and hand lengths, and handheld dynamometers were used to measure wrist, grip, and finger strength. Ball spin was measured using a 3-dimensional Doppler radar and video system. Standard multiple regression analyses showed no significant relationships existed between ball spin and any of the upper-extremity ROM or limb length variables (R2 = 0.01-0.03; p = 0.40-0.94). However, there was a significant relationship for the summation of wrist strength (R2 = 0.24, p = 0.03). Both time to wrist extension strength {B = 0.50 (95% confidence interval [CI]: 0.23-0.76), p = 0.001} and radial deviation strength (B = 0.41 [95% CI: 0.15-0.66], p = 0.002) were significant predictors within this model. These results demonstrate that the rate of ball spin during a pitch may be partially altered by increasing wrist extension acceleration and radial deviation strength. However, the subsequent clinical measurements of shoulder, elbow, wrist, and finger ROM, arm and hand length, and grip and finger strength were not associated with ball spin.

One of the traditional perfections of Scripture according to historic Protestant orthodoxy, alongside inspiration, authority, and clarity, is sufficiency. Biblicists have taken this ball and run with it, insisting that everything we need to know, not only for salvation but for much else, is in the Bible. This essay attempts to clarify the concept of Scripture’s sufficiency by reviewing its history and by specifying how, and for what, it is “enough.” This involves distinguishing between formal and material sufficiency, and drawing distinctions between sources, resources, and norms. The paper argues that the sufficiency of Scripture must be understood alongside the principle of sola scriptura, and that the Bible alone is enough for ruling the church’s social imaginary, especially as this concerns the story of what God is doing in creation and redemption. Scripture is sufficient for understanding extra-biblical knowledge in the framework of biblical narrative and for perceiving reality as sustained and directed by the triune God. The essay concludes by offering recommendations for understanding the sufficiency of Scripture both in its proper domain (saving knowledge) and in areas outside its proper domain, such as the natural and social sciences, including psychology.

This paper reports a demonstration of a 90 min on-demand class where a chemical experiment is performed to educate nonscience majors on surfactants. First-year undergraduate students perform the wa...

This study designs, fabricates and tests a piezoelectric pump with the structure of a polystyrene ball check valve. The structure of the check valve consists of three layers of specially designed polymethylmethacrylate plates and six polystyrene balls, which forms a particular three-layer constraint mechanism to limit the lateral and vertical displacement of the balls. The assembly of the ball valve can be completed with a simple placing operation, which simplifies the assembly process of the entire pump. The balls are lightweight, which is beneficial for working at high frequencies. The current design adopts two compressible spaces, and the equivalent analogue circuit of compressible spaces is established and analysed. Experimental results indicate that compressible spaces can alleviate the burden in the actuator and smoothen the flow rate pulsation in the long flow channel. The theoretical analysis and experimental tests reveal that this new piezoelectric pump is self-priming. A high flow rate of 99.6 mL/min and the maximum back pressure of 15.3 kPa are obtained when the pump is driven with a sinusoidal voltage of 448 Vpp at the resonant frequency of 790 Hz.

One-Class Classification (OCC) is a supervised learning technique for classification whereby the classifier is obtained only by training the objects from the target class and identifying whether new observations belong to the class or not. In this paper, we propose a novel approach to OCC, which is based on optimal covering of the target objects by ‘good’ norm balls. The proposed classifier consists of the selected norm balls from an integer programming model where the finite norm ball candidates from the target objects are used. Computational experiments were carried out to examine the performance and characteristics of the proposed classifier using artificial and real data from the UCI Repository. The results showed that the proposed model was comparable to existing OCC methods in the comparison group. In addition, the proposed model demonstrated high sparsity leading to low testing burden and robustness to noises.

Ball screws, the most frequently used mechanical components to transform rotary motion into linear motion, can directly affect the precision and service life of engineering machines. Once the efficiency and accuracy of ball screws degrades, the performance and safety of machines are hard to guarantee. Conventional fault diagnosis researches of ball screws are mainly focused on ordinary faults such as preload loss and wear, and lack of the researches on early faults such as lubrication degradation which may progress into the ordinary faults. Additionally, the fault diagnosis models proposed in previous studies divide the fault diagnosis into two separated stages: feature extraction and fault classification, which prevents the usage for real-time applications. The specifically designed algorithm in features extraction stage may be also not workable on other objects. To tackle these drawbacks, this paper proposes a highly accurate early fault diagnosis model of ball screws based on a state-of-the-art deep learning technique, called One-Dimensional Convolutional Neural Network (1-D CNN). Experiments simulating the lubrication degradation of ball screws are specially designed for the early fault diagnosis of the ball screws. Moreover, a concise and efficient approach based on orthogonal design is exploited to scientifically obtain the optimal parameters of the 1-D CNN. The results of a case study verify the superiority of the proposed method in establishing a highly accurate 1-D CNN based fault diagnosis model.

The Montney tight siltstone reservoir is a multi-stacked play, which covers a total area of 130,000 km2 along the Alberta–British Columbia border in Western Canada. Since the late 1990s, different fracturing methods and fluids have been tested in 4000-plus Montney wells to find the optimal fracturing method and fluid. The previous studies reviewing the performance of fracturing methods in Montney do not represent a holistic evaluation of these methods, owing to some limitations, including: (1) using a small sample size, (2) having a limited scope by focusing on a specific aspect of fracturing (method/fluid), (3) relying on data analytics approaches that offer limited subsurface insight, and (4) generating misleading results (e.g., on optimum fracturing method/fluid) through using disparate data that are unstructured and untrustworthy as a result of significant regional variations in true vertical depth (TVD), geological properties, fluid windows, completed lateral length, fracturing method/fluid/date, and drawdown rate management and choke size strategy. The present study eliminates these limitations by rigorously clustering 4000-plus Montney wells based on the TVD, fluid window, completed lateral length, fracturing method/fluid/date, and drawdown rate strategy to isolate the effect of each fracturing method by comparing each well’s production to that of its offsets, which use different fracturing methods but possess similar geology, fluid window, and TVD. With similar TVD, fracturing fluid, and completion date, wells completed with pinpoint fracturing method outperform their offsets completed with ball-and-seat and plug-and-perforate (PnP) fracturing methods. However, wells completed with ball-and-seat and PnP methods that outperform their offset pinpoint wells have either: (1) been fractured one to four years earlier than the pinpoint wells and/or (2) used energized oil-based fluid, hybrid fluid, and energized slickwater versus slickwater used in the pinpoint offsets. This suggests that the water-phase trapping is more severe in these pinpoint wells attributable to the use of slickwater. Previous studies often favored one specific fracturing method or fluid without highlighting these complex interplays between the type of fracturing method, fracturing fluid, completion date (regional depletion or well vintage), and the reservoir properties and hydrodynamics.

Intermetallic is a critical factor that is controlled and limit during manufacturing of integrated units. Through improving the ball flatness response of the semiconductor wire significantly impact the outcome for the intermetallic characteristic between metal such as Gold-Aluminum connection. The implementation of this study on the actual manufacturing control eliminates escapee of poor intermetallic that would impact the reliability and integrity of the package upon its application to the end product.

The world of sports intrinsically involves fast and complex events that are difficult for coaches, trainers and players to analyze, and also for audiences to follow. In fast paced team sports such as soccer, keeping track of all the players and analyzing their performance after every match are very challenging. Current scenarios for identifying the best talents in soccer involve word-of-mouth and coaches/recruiters scouring through hours of manually annotated videos. This is a very expensive and laborious process and also biased by the nature of the recruiters. To alleviate these problems, this paper proposes an automated system that can detect, track, classify the teams of multiple players and identify the player controlling the ball in a video. The system generates three very important tactical statistics for a player: 1) duration of ball possession, 2) number of successful passes and 3) number of successful steals. This is done by training Convolutional Neural Networks (CNNs) to (a) localize and track the players on the field, (b) classify the team of a detected player, (c) identify the player controlling the ball and (d) pooling all the information extracted from (a), (b), and (c) to generate the statistics of players. To overcome the problem that the features learned from specific soccer matches do not necessarily generalize across different soccer matches, the paper proposes minimal amount of match-specific annotation and data augmentation, using a variant of Deep Convolutional Generative Adversarial Networks (DCGAN) to improve the accuracy. Experimental results and ablation studies show that the proposed approach outperforms the state-of-the-art approaches in terms of accuracy and processing speed.

A simple experiment carried out with readily available equipment is used to investigate the interesting physics that occurs when a ball is bounced on a flat surface and left to continue bouncing until it stops. A solution well known from introductory physics courses is that if a ball loses a fraction of its energy on each bounce, then it will bounce infinitely many times in a finite time interval. A convolutional model of the sound a bouncing ball makes is created using an impulse response function and a prediction based on energy loss that the sound amplitudes will decay linearly to zero as the ball stops bouncing. Strategies for data analysis using correlation and deconvolution with the impulse response function are shown to simplify the picking of bounce times. Observations from several data examples show that the convolutional model is a good description of the real data and that we observe a linear decrease in sound amplitude consistent with the model prediction.

Anyone who has visited a science museum has seen the demonstration where a beach (or ping-pong) ball is suspended in mid-air at a fixed position by constant blowing from below. After a while, the ball inevitably tumbles to the ground but can easily be rebalanced, by hand, again at the suspension point. Here, we ask a different more delicate question. Can we blow the ball from rest, starting at the nozzle opening (x = 0), moving it up to the suspension point x = x* above the nozzle? We show that it is not possible to do this using constant blowing because the point at which the downward gravitational force balances the upward blowing force is an elliptic fixed point of the governing equations, so there is no transfer trajectory that connects the origin to x*. To overcome this problem, we design time-dependent blowing schedules that achieve the transfer, making use of orbit transfer ideas developed in the orbital mechanics literature. Then, we ask which of these time-dependent schedules are optimal? We show that, generally, it is bang–bang (on–off) blowing schedules that achieve the transfer in minimal time, using minimal energy (action) and minimal air volume. For certain parameter values, however, there are more complicated blowing schedules that are optimal (with respect to energy), which can be designed using the Pontryagin Maximum Principle (PMP) and singular control. We use elementary concepts from mechanics, nonlinear dynamics, and control theory and challenge the inclined experimentalist to try to implement some of these nonconstant blowing schedules in the lab.

Objectives:\ud Cricket administrators have started scheduling long-form matches which finish at night and are played with a pink as opposed to a red ball. However, there are reports that the pink ball may introduce new dangers and alter performance. The aim of this study was to investigate professional cricketers’ opinions about the visibility of the pink ball whilst playing in different lighting conditions (afternoon, dusk and night).\ud \ud Design:\ud Purposeful sampling of a cross-section of elite cricketers with pink ball experiences playing in the United Kingdom.\ud \ud Methods:\ud Eighty-eight international or first-class professional cricketers completed a questionnaire consisting of Likert scale and free text responses to questions covering perceptions of the pink ball, with a particular emphasis on visibility.\ud \ud Results:\ud The pink ball was reported as less visible than the red ball when batting (p

The existence of three walls on both court sides in padel is a unique characteristic from which particular offensive and defensive behaviours emerged. The aim of this study was to assess the differ...

ERSOW is the name of a wheeled soccer robot that competes in the Kontes Robot Sepak Bola Indonesia (KRSBI). The soccer robot plays a soccer game based on the rules adapted from the human soccer game. The ERSOW team was formed in 2016. Starting in 2017, ERSOW participated in the KRSBI with the Middle Size League (MSL) type. Research in the field of wheeled soccer robots is mostly carried out on robot intelligence, such as how robots detect and look for balls, dribble, pass the ball, avoid opponents, and communicate in teams. This research focuses on the ability that the robot can pass the ball in KRSBI 2020. There are adjustments to the rules for its implementation online where the robot has to pass the ball and score as many goals as possible. The robot's ability to know the direction of ball movement and cut the ball movement or intercept is needed. By utilizing data processing from vision to obtain ball speed data and speed algorithm calculations, the passing ball method has a small chance of missing. Based on the results of experiments that have been carried out, the success of ERSOW in passing using this method is 94.7%.

Ball-on-socket articulation is the major structural type of artificial joints. The insight on the mechanical and bio-tribological characteristics of this structure is important for designing both the device itself and its wear assessment regime. Two kinds of ball-on-socket structures were studied including a simplified general model and a real artificial cervical disc. The bio-tribological behaviors were evaluated by in vitro wear simulation method using four kinds of pairs with different combinations of structure, frictional material and testing duration under alternate motion of FE-AR (flexion extension and axial rotation) and LB-AR (lateral bending and axial rotation). In order to analyze the formation mechanism of representative wear characteristics, the mechanical behaviors were also studied by finite element analysis method. The results indicated that there were similar mechanical and bio-tribological characteristics for these two structures after about 9 MC (Million Cycles) tests. Under the axial load, it revealed more serious wear severity in the edge region than that in the central region for both convex polymer component and concave metal component, which may be due to much higher values of equivalent stress and equivalent elastic strain in the edge region than that in the central region. Under FE (flexion extension) or LB (lateral bending) motion, it showed common wide and curved wear grooves with ring distribution in the edge region for both ball component and nucleus pulposus component, which may be attributed to the higher equivalent stress and equivalent elastic strain at the limit position. It just indicated several sliding scratches for TC4 (Ti6Al4V alloy) metal component with an abrasive wear mechanism, while it revealed plastic deformation, surface cracks, sliding scratches and wear grooves for XPE (crosslinking polyethylene) polymer component with a mix of abrasive wear and adhesive wear mechanism. Hence, there was a strong correlation between structural design and bio-tribological characteristics for ball-on-socket prostheses.

Droplet shear stress is the main cause of soil erosion under sprinkler irrigation, and the effect of droplet impact angle on the shear stress distribution cannot be ignored. In this study, a ball-driven sprinkler was selected to investigate the radial distributions of droplet impact angles under three operating pressures (0.25, 0.30, and 0.35 MPa) and two nozzle diameters (1.9 and 2.2 mm), which are commonly used in agricultural irrigation. The effect of droplet impact angles on the distances from the sprinkler, droplet impact velocities, and shear stresses were analyzed by a 2DVD instrument. Irrespective of the nozzle diameter or operating pressure, the droplet velocities and impact angles near the sprinkler were distributed at 1.0–5.5 m s−1 and 70–90°, respectively, and the droplet shear stress increased with the distance from the sprinkler. Suitable operating pressure and distance from the sprinkler significantly reduced the droplet shear stress. Although the nozzle diameter had a certain effect on the maximum shear stress, the overall effect was insignificant. We developed the models for the radial distribution of droplet shear stresses, which were in good agreement with the measurement. This study proposes a new method for accurately predicating the soil erosion under sprinkler irrigation. HIGHLIGHTS The soil erosion risk at the end of the spray jet is highly related to droplet shear stress rather than droplet kinetic energy.; Increasing the operating pressure or decreasing the nozzle diameter can effectively reduce the maximum droplet shear stress.; Mathematical models are developed for predicting the radial distribution of droplet shear stress.

The Dragon Festival Ball, first held at the glamorous Trocadero Palais de Danse in 1938, remains one of the best-remembered historical events associated with Sydney’s Chinese community. Effectively...

UDC 514.13, 515.12, 513.83, 517.5 We consider the problem of shadow in the Lobachevsky space. This problem can be treated as the problem of finding the conditions that ensure that the points belong to the generalized convex hull of a family of sets. We determine the boundary values of parameters, for which the same configurations of balls ensure that the point belongs to a generalized convex hull of balls in the Euclidean and hyperbolic spaces. In addition to balls, we consider families of horoballs, as well as combinations of balls and horoballs.

The ultimate goal of photocatalytic CO2 reduction is to achieve high selectivity for a single product with high efficiency. One of the most significant challenges is that expensive catalysts prepared through complex processes are usually used. Herein, gram-scale cubic silicon carbide (3C-SiC) nanoparticles are prepared through a top-down ball-milling approach from low-priced 3C-SiC powders. This facile mechanical milling strategy ensures large-scale production of 3C-SiC nanoparticles with an amorphous silicon oxide (SiOx) shell and simultaneously induces abundant surface states. The surface states are demonstrated to trap the photogenerated carriers, thus remarkably enhancing the charge separation, while the thin SiOx shell prevents 3C-SiC from corrosion under visible light. The unique electronic 3C-SiC tackles the challenge associated with low selectivity of photocatalytic CO2 reduction to C-1 compounds. In conjugation with efficient water oxidation, 3C-SiC nanoparticles can reduce CO2 into CH4 with selectivity over 90%. Funding Agencies|Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (FORMAS)Swedish Research Council Formas [2016-00559]; Swedish Research Council (Vetenskapsradet)Swedish Research Council [2018-04670]; Swedish Foundation for International Cooperation in Research and Higher Education (STINT) [CH2016-6722]; AForsk Foundation [18-370]; Stiftelsen Olle Engkvist ByggmastareSwedish Research Council [189-0243]