Journal articles on the topic 'Soccer field size'
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Ortega-Toro, Enrique, Antonio García-Angulo, José-María Giménez-Egido, Francisco J. García-Angulo, and José Palao. "Effect of modifications in rules in competition on participation of male youth goalkeepers in soccer." International Journal of Sports Science & Coaching 13, no. 6 (April 11, 2018): 1040–47. http://dx.doi.org/10.1177/1747954118769423.
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The purpose of this study was to assess the effect of modifications in field size, number of players, and goal size on the goalkeeper's actions in competition in male youth soccer ( n = 4) (under-12). A quasi-experimental design was implemented to measure the effects of the changes in the number of players per team (8-a-side vs. 5-a-side), goal size (6 × 2 m vs. 3 × 2 m), and field size (58 × 38 m vs. 38 × 20 m) on the offensive and defensive technical and tactical actions of the goalkeeper. Four male under-12 goalkeepers (age = 11.33 ± 0.6 years, average weekly training = 2.45 ± 0.3 h, and years of experience = 4.8 ± 0.9 years) were analyzed in three tournaments (8-a-side; 5-a-side; 8-a-side). The dependent variables were: defensive and offensive technical actions taken by the goalkeepers and the way their actions were carried out. The results show that in the 5-a-side soccer matches, goalkeepers carried out more defensive actions (8-a-side: 31.2 ± 3.8; 5-a-side: 77.75 ± 5.0; 8-a-side: 39.5 ± 6.0; F2,6 = 111,218, p = .000, η2 = .974; ES .998) and offensive actions (8-a-side: 58.0 ± 7.1; 5-a-side: 84.0 ± 13.5; 8-a-side: 58.1 ± 9.2; F2,6 = 16,257, p = .004, η2 = .844; ES .996) than in 8-a-side soccer matches. The reduction in field size, number of players, and goal size resulted in under-12 goalkeepers having more interaction and more variability in their actions. This information could help the different stakeholders to adapt or design the youth soccer competition rules in a way that allows goalkeepers to have more experiences.
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Bidaurrazaga-Letona, Iraia, Humberto Moreira Carvalho, José António Lekue, Aduna Badiola, António José Figueiredo, and Susana María Gil. "Applicability of an agility test in young players in the soccer field." Revista Brasileira de Medicina do Esporte 21, no. 2 (April 2015): 133–38. http://dx.doi.org/10.1590/1517-869220152102144406.
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INTRODUCTION: in soccer, agility is a relevant parameter that is defined as the ability to change the direction of the body rapidly and is a result of a combination of strength, speed, balance and coordination.OBJECTIVE: to demonstrated the reliability and validity of the modified Barrow test in soccer players aged 10 to 14 years, analyze its relationship with age, maturation, experience and body size and test the effectiveness of the protocol for distinguishing performance changes during a 10-month competitive season.METHODS: fifty-one adolescent Basque soccer players were enrolled. Age, maturation, experience, body size, vertical jump and 15-m sprint were measured. The reliability of the test was analyzed using replicate tests in a subgroup n= 34. Another subgroup of 33 players n =18, under-11, 10.4 ± 0.3 years; n = 15 under-13, 12.0 ± 0.8 years was evaluated at the beginning and the end of the season.RESULTS: the reliability of the test was good change in mean = -0.5%, 95% CI -1.2 to 0.2, SD=0.14; coefficient of variation = 0.9%, 95% CI - 0.7 to 1.5, SD=0.25. Chronological age and adiposity were significant predictors of agility performance P<0.01. An improvement in performance was observed over a 10-month soccer season, with a significant group effect P<0.01.CONCLUSION: the agility test demonstrated logic and validity, and proved to be a reliable and objective instrument for assessing adolescent soccer players.
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García-Angulo, Antonio, Enrique Ortega-Toro, José María Giménez-Egido, Aurelio Olmedilla, Alexandre García-Mas, and José Manuel Palao. "Does Youth Soccer Players’ Group Cooperation Improve when Pitch, Goal, and Team Size Are Reduced?" Journal of Human Kinetics 78, no. 1 (March 1, 2021): 151–60. http://dx.doi.org/10.2478/hukin-2021-0035.
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Abstract The aim of this study was to analyse the effects of the modification of the pitch size, goal size, and the number of players per team on the level of cooperation in youth soccer players (U-12). A quasi-experimental design was implemented to measure the effects of the changes in the number of players per team (8-a-side vs. 5-a-side), goal size (6 x 2 m vs. 3 x 2 m), and field size (58 x 38 m vs. 38 x 20 m) on the cooperation. Four soccer teams under-12 (n = 48 players) participated in three tournaments (standard rules; proposed rules; standard rules). The five variables of cooperation were measured using the “Sports Cooperation Questionnaire”: conditional cooperation, cooperation with the coach, disposition of unconditional cooperation, situational cooperation with teammates, and situational cooperation outside the field of play. Players presented the same level of cooperation in conditional cooperation, situational cooperation with teammates, and situational cooperation outside the field of play with both types of rules. The modification of rules involved a reduction of the cooperation with the coach and a disposition of unconditional cooperation. The causes of the reduction may be related to players’ adaptation to new tactical dispositions and game situations. Future studies are needed of player’s cooperation and different competition rules in youth sports.
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Bradbury, John Charles. "Determinants of Attendance in Major League Soccer." Journal of Sport Management 34, no. 1 (January 1, 2020): 53–63. http://dx.doi.org/10.1123/jsm.2018-0361.
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This study examines the determinants of Major League Soccer team attendance during the league’s recent era of growth. The estimates indicated that regular-season on-field performance is positively associated with attendance, but the returns to success are diminishing. The estimates identified positive novelty effects for newer teams and soccer-specific stadiums, but not for stadium age. Income and attendance were positively correlated, which indicates that Major League Soccer matches are a normal good. The population size, Hispanic share of the population, presence of other major-league franchises, and number of designated players on a team did not appear to be strong determinants of seasonal attendance.
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Belozo, Felipe Lovaglio, Eliel Calazans Ferreira, Guilherme Vinicius Moreira Grandim, Cristian Javier Ramirez Lizana, João Claudio Pereira Machado, Vagner Ramon Rodrigues Silva, and Alcides José Scaglia. "EFFECT OF GAME FORMAT ON THE INTENSITY OF SOCCER TRAINING." Revista Brasileira de Medicina do Esporte 24, no. 2 (March 2018): 149–52. http://dx.doi.org/10.1590/1517-869220182402181159.
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ABSTRACT Introduction: During training in games, it is essential to know how to correctly manipulate the formats of the games (size of field and number of players). Objective: The aim of this study was to evaluate the influence of three different game formats on the kinematic variables of training in soccer players. Methods: For this purpose, eleven U-20 soccer players participated in three games formats, Gr+3vs3+Gr, Gr+6vs6+Gr and Gr+10vs10+Gr in two conditions (experimental and conceptual). Through videogametry, it was possible to determine the range of speeds covered by the players during the games and to correlate with the ventilatory threshold (VT) evaluation individually to establish four different intensity zones (low intensity, moderate intensity, moderate/high intensity or high intensity). Results: It was verified that in the experimental games, when increasing the size of the field there were significant increases in the intensity of the game. In the conceptual games, there were only significant increases of the field Gr+10vs10+Gr for the games Gr+6vs6+Gr and Gr+3vs3+Gr. Conclusion: It is concluded that the format of the games has a significant effect on the movement of players. Level of Evidence III; Case-control study.
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Yang, Tianwu, Changjiu Zhou, and Mohan Rajesh. "A Fast Vision System for Soccer Robot." Applied Bionics and Biomechanics 9, no. 4 (2012): 399–407. http://dx.doi.org/10.1155/2012/480718.
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This paper proposes a fast colour-based object recognition and localization for soccer robots. The traditional HSL colour model is modified for better colour segmentation and edge detection in a colour coded environment. The object recognition is based on only the edge pixels to speed up the computation. The edge pixels are detected by intelligently scanning a small part of whole image pixels which is distributed over the image. A fast method for line and circle centre detection is also discussed. For object localization, 26 key points are defined on the soccer field. While two or more key points can be seen from the robot camera view, the three rotation angles are adjusted to achieve a precise localization of robots and other objects. If no key point is detected, the robot position is estimated according to the history of robot movement and the feedback from the motors and sensors. The experiments on NAO and RoboErectus teen-size humanoid robots show that the proposed vision system is robust and accurate under different lighting conditions and can effectively and precisely locate robots and other objects.
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Xiong, Dan, Junhao Xiao, Huimin Lu, Zhiwen Zeng, Qinghua Yu, Kaihong Huang, Xiaodong Yi, and Zhiqiang Zheng. "The design of an intelligent soccer-playing robot." Industrial Robot: An International Journal 43, no. 1 (January 18, 2016): 91–102. http://dx.doi.org/10.1108/ir-05-2015-0092.
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Purpose – The purpose of this paper is to design intelligent robots operating in such dynamic environments like the RoboCup Middle-Size League (MSL). In the RoboCup MSL, two teams of five autonomous robots play on an 18- × 12-m field. Equipped with sensors and on-board computers, each robot should be able to perceive the environment, make decision and control itself to play the soccer game autonomously. Design/methodology/approach – This paper presents the design of our soccer robots, participating in RoboCup MSL. The mechanical platform, electrical architecture and software framework are discussed separately. The mechanical platform is designed modularly, so easy maintainability is achieved; the electronic architecture is built on industrial standards using PC-based control technique, which results in high robustness and reliability during the intensive and fierce MSL games; the software is developed upon the open-source Robot Operating System (ROS); thus, the advantages of ROS such as modularity, portability and expansibility are inherited. Findings – Based on this paper and the open-source hardware and software, the MSL robots can be re-developed easily to participate in the RoboCup MSL. The robots can also be used in other research and education fields, especially for multi-robot systems and distributed artificial intelligence. Furthermore, the main designing ideas proposed in the paper, i.e. using a modular mechanical structure, an industrial electronic system and ROS-based software, provide a common solution for designing general intelligent robots. Originality/value – The methodology of the intelligent robot design for highly competitive and dynamic RoboCup MSL environments is proposed.
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Carlos-Vivas, Jorge, Elena Marín-Cascales, Tomás T. Freitas, Jorge Perez-Gomez, and Pedro E. Alcaraz. "Force-Velocity-Power Profiling During Weighted-Vest Sprinting in Soccer." International Journal of Sports Physiology and Performance 14, no. 6 (July 1, 2019): 747–56. http://dx.doi.org/10.1123/ijspp.2018-0490.
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Purpose: To describe the load–velocity relationship and the effects of increasing loads on spatiotemporal and derived kinetic variables of sprinting using weighted vests (WV) in soccer players and determining the load that maximizes power output. Methods: A total of 23 soccer players (age 20.8 [1.5] y) performed 10 maximal 30-m sprints wearing a WV with 5 different loads (0%, 10%, 20%, 30%, and 40% body mass [BM]). Sprint velocity and time were collected using a radar device and wireless photocells. Mechanical outputs were computed using a recently developed valid and reliable field method that estimates the step-averaged ground-reaction forces during overground sprint acceleration from anthropometric and spatiotemporal data. Raw velocity–time data were fitted by an exponential function and used to calculate the net horizontal ground-reaction forces and horizontal power output. Individual linear force–velocity relationships were then extrapolated to calculate the theoretical maximum horizontal force (F0) and velocity and the ratio of force application (proportion of the total force production that is directed forward at sprint start). Results: Magnitude-based inferences showed an almost certain decrease in F0 (effect size = 0.78–3.35), maximum power output (effect size = 0.78–3.81), and maximum ratio of force (effect size = 0.82–3.87) as the load increased. The greatest changes occurred with loads heavier than 20% BM, especially in ratio of force. In addition, the maximum power was achieved under unloaded conditions. Conclusions: Increasing load in WV sprinting affects spatiotemporal and kinetic variables. The greatest change in ratio of force happened with loads heavier than 20% BM. Thus, the authors recommend the use of loads ≤20% BM for WV sprinting.
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Peráček, Pavol, Matúš Bôžik, and Martin Mikulič. "Internal Load of Elite Malaysian Young Soccer Players in Small Sided Games with Different Parameters." Acta Facultatis Educationis Physicae Universitatis Comenianae 58, no. 1 (May 1, 2018): 32–43. http://dx.doi.org/10.2478/afepuc-2018-0004.
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Summary The aim of the study was to extend the knowledge about the internal load of elite young soccer players in small sided games with different parameters in the category under 19 years. The group consisted of 16 elite soccer players under the age of 19. This team competed in the first league of the same age category We have monitored the time spent by players in bio-energy load zones (percentage of maximum heart rate), in small sided games with 2 players against 2, 3 against 3, with the size of the playing field of 25 × 18 meters and 30 × 25 meters. We used basic mathematical and statistical characteristics and Wilcoxon t-test for non-parametric selections. Our study confirmed that in the category under 19 years is valid that the larger number of players (3:3) in small sided games, indicates the players to spend more time in bio-energy zones 4 and 5. Direct correlation also applies to the size of the playing field, depending on the time spent in the load zones 4 and 5. The larger dimension of the pitch indicates to more time the players spend in bio-energy load zones, which is considered to be focal for us. If we want to use them as a way of complex training program (game training), then the small sided games are suitable training strategy.
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Hong, Wei, Yan Hui Zhang, Yan Tao Tian, and Chang Jiu Zhou. "Color Image Processing and Self-Localization for a Humanoid Soccer Robot." Applied Mechanics and Materials 461 (November 2013): 877–85. http://dx.doi.org/10.4028/www.scientific.net/amm.461.877.
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The paper proposed a series of image processing algorithm to recognize the evidences in an image accurately for humanoid soccer robot, such as color image segmentation based on HSV model, edge detection based on four linear operator, field straight line extraction by Hough transform based on 8-neighbhour connected domain clusters and identification of line intersection shape based on Hopfield network. Based on evidences from image processing, Piecewise Monte Carlo localization is presented to solve kidnap problem so that localization of humanoid robot can be not only adapt to rule changes for competition, but also be more efficient and robust. The effectiveness of the piecewise MCL is verified by RoboCup Adult Size humanoid soccer robot, Erectus. The experimental results showed that the humanoid robot was able to solve the kidnap problem adaptively with two strategies: resetting or revising, in which resetting was more efficient than revising gradually.
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Mikulič, Martin. "Vybrané charakteristiky vnútorného zaťaženia elitných mladých futbalistov v prípravných hrách s rôznymi parametrami." Studia sportiva 12, no. 2 (January 3, 2019): 79–86. http://dx.doi.org/10.5817/sts2018-2-8.
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The main aim of the study was to find more information about the internal load of elite young soccer players in small-sided games with different parameters. The group consisted of elite soccer players (n = 16) in under 15 years category. The team participated in the 1st Slovak league. We've tracked the time spent by players in selected bioenergetics load zones (% of maximum HR) during small-sided games with 2:2, 3:3 players and 25x18-meter and 30x25-meter playing field. We used the basic mathematical-statistical characteristics and Wilcoxon t-test for non-parametric selections. We found that in the category under 15 years, a larger number of players (3: 3) in the small-sided games indicates less time spent in bio-energy zones 4. and 5. Indirect intentions also apply to the dimensions of the playing field, depending on the time spent in load zones no. 4. and 5. That means that the larger the size of the playing field causes less time spent by players in bio-energy load zones that are imported to us. If we want to use them as a comprehensive training tool (game training), this is what we consider to be an adequate training tool.
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Padua, Darin A., Lindsay J. DiStefano, Anthony I. Beutler, Sarah J. de la Motte, Michael J. DiStefano, and Steven W. Marshall. "The Landing Error Scoring System as a Screening Tool for an Anterior Cruciate Ligament Injury–Prevention Program in Elite-Youth Soccer Athletes." Journal of Athletic Training 50, no. 6 (June 1, 2015): 589–95. http://dx.doi.org/10.4085/1062-6050-50.1.10.
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Context Identifying neuromuscular screening factors for anterior cruciate ligament (ACL) injury is a critical step toward large-scale deployment of effective ACL injury-prevention programs. The Landing Error Scoring System (LESS) is a valid and reliable clinical assessment of jump-landing biomechanics. Objective To investigate the ability of the LESS to identify individuals at risk for ACL injury in an elite-youth soccer population. Design Cohort study. Setting Field-based functional movement screening performed at soccer practice facilities. Patients or Other Participants A total of 829 elite-youth soccer athletes (348 boys, 481 girls; age = 13.9 ± 1.8 years, age range = 11 to 18 years), of whom 25% (n = 207) were less than 13 years of age. Intervention(s) Baseline preseason testing for all participants consisted of a jump-landing task (3 trials). Participants were followed prospectively throughout their soccer seasons for diagnosis of ACL injuries (1217 athlete-seasons of follow-up). Main Outcome Measure(s) Landings were scored for “errors” in technique using the LESS. We used receiver operator characteristic curves to determine a cutpoint on the LESS. Sensitivity and specificity of the LESS in predicting ACL injury were assessed. Results Seven participants sustained ACL injuries during the follow-up period; the mechanism of injury was noncontact or indirect contact for all injuries. Uninjured participants had lower LESS scores (4.43 ± 1.71) than injured participants (6.24 ± 1.75; t1215 = −2.784, P = .005). The receiver operator characteristic curve analyses suggested that 5 was the optimal cutpoint for the LESS, generating a sensitivity of 86% and a specificity of 64%. Conclusions Despite sample-size limitations, the LESS showed potential as a screening tool to determine ACL injury risk in elite-youth soccer athletes.
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da Silva, Cristiano D., and Ric Lovell. "External Validity of the T-SAFT90: A Soccer Simulation Including Technical and Jumping Activities." International Journal of Sports Physiology and Performance 15, no. 8 (September 1, 2020): 1074–80. http://dx.doi.org/10.1123/ijspp.2019-0057.
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Purpose: To examine the physiological, muscle-damage, endocrine, and immune responses to a modified soccer-simulation protocol to include technical and jumping activities characteristic of match play (the Technical Soccer-Specific Aerobic Field Test; T-SAFT90). Methods: Eighteen university players (age 23 [2] y, stature 175 [5] cm, body mass 74 [11] kg) performed the 90-minute protocol, with acute physiological responses monitored via heart rate, ratings of perceived exertion (6–20 scale), and body mass changes. Creatine kinase, myoglobin, cortisol, and leukocyte subset concentrations were measured at baseline, immediately (0 h), and 24 hours post T-SAFT90. Results: T-SAFT90 incurred an average heart rate equivalent to 87% (5%) of maximum, 16 (2) a.u. ratings of perceived exertion, and a 1.5% (1.0%) body mass deficit. Moderate to large proliferation of leukocyte subsets (P ≤ .01; leukocytes: 6.4-fold; neutrophils: 5.5-fold; lymphocytes: 2.0-fold) and increases in cortisol (2.3-fold) were observed at 0 hours (effect size = 1.13–3.52), each returning to baseline by 24 hours (P > .45; effect size = 0.05–0.50). Myoglobin peaked immediately post T-SAFT90 (4.8-fold), whereas creatine kinase (24 h: 6.0-fold) showed a delayed time course (both P ≤ .001; very large effects; effect size = 2.66 and 3.43, respectively). Conclusions: The magnitude and time course of the physiological, immune, endocrine, and muscle-damage markers observed during and following T-SAFT90 are similar to values reported in match-play literature, demonstrating external validity of the simulation.
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Clemente, Filipe Manuel, Adam Owen, Jaime Serra-Olivares, Acácio Correia, João Bernardo Sequeiros, Frutuoso GM Silva, and Fernando Manuel Lourenço Martins. "The effects of large-sided soccer training games and pitch size manipulation on time–motion profile, spatial exploration and surface area: Tactical opportunities." Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology 232, no. 2 (August 7, 2017): 160–65. http://dx.doi.org/10.1177/1754337117722658.
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Analysis of the physical, technical and physiological variations induced through the use of different soccer game formats have been widely discussed. However, the coaching justification for the specific use of certain game formats based on individual and collective spatial awareness is unclear. As a result, the purpose of this study was to analyze 11 versus 11 game formats conducted across two pitch sizes (half-size: 54 m × 68 m vs full-size: 108 m × 68 m) to identify effects of time–motion profiles, individual exploration behavior and collective organization. A total of 10 amateur soccer players from the same team (23.39 ± 3.91 years old) participated in this study. Data position of the players was used to calculate the spatial exploration index and the surface area. Distances covered in different speeds were used to observe the time–motion profile. The full-size pitch dimensions significantly contributed to greater distances covered via running (3.86–5.52 m s−1) and sprinting (>5.52 m s−1). Total distance and number of sprints were also significantly greater in the full-size pitch as compared to the half-size pitch. The surface area covered by the team (half-size pitch: 431.83 m2 vs full-size pitch: 589.14 m2) was significantly larger in the full-size pitch condition. However, the reduced half-size pitch significantly contributed to a greater individual spatial exploration. Results of this study suggest that running and sprinting activities increase when large, full-size pitch dimensions are utilized. Smaller surface area half-size pitch contributes to a better exploration of the pitch measured by spatial exploration index while maintaining adequate surface area coverage by the team. In conclusion, the authors suggest that the small half-size pitch is more appropriate for low-intensity training sessions and field exploration for players in different positions. Alternatively, the large full-size pitch is more appropriate for greater physically demanding training sessions with players focused on positional tactical behavior.
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Castillo, Daniel, Javier Yanci, and Jesús Cámara. "Impact of Official Matches on Soccer Referees’ Power Performance." Journal of Human Kinetics 61, no. 1 (March 23, 2018): 131–40. http://dx.doi.org/10.1515/hukin-2017-0116.
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Abstract The evaluation of match officials’ neuromuscular performance is now an important consideration and the vertical jump test is considered suitable for assessing lower limb power, partly because it is directly related to refereeing. The aim of this study, therefore, was to determine the effect of soccer matches on match officials’ vertical jump performance by assessing various biomechanical variables. Eighteen field referees (FRs) and 36 assistant referees (ARs) who officiated in 18 official matches participated in this study. Before the match, at half time and immediately after the match, officials performed two countermovement jumps. Flight phase time (FT), maximum force production (MFpropulsion), time to production of maximum force (TMFpropulsion), production of maximum power (MP), maximum landing force (MFlanding) and time to stabilization (TTS) were calculated for all jumps. There was a tendency for match officials’ jumping performance to improve after matches than beforehand (FR: effect size (ES) = 0.19 ± 0.36, possibly trivial; AR: ES = 0.07 ± 0.17, likely trivial). There were also likely small and very likely moderate differences between FRs’ MP in pre-match and half-time jumps (ES = 0.46 ± 0.47) and in their pre- and post-match jumps (ES = 0.71 ± 0.48). These results indicate that refereeing soccer matches does not reduce vertical jump performance; the subsequent neuromuscular fatigue is not sufficient to affect landing technique.
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Silva, Bernardo, Júlio Garganta, Rodrigo Santos, and Israel Teoldo. "Comparing Tactical Behaviour of Soccer Players in 3 vs. 3 and 6 vs. 6 Small-Sided Games." Journal of Human Kinetics 41, no. 1 (July 8, 2014): 191–202. http://dx.doi.org/10.2478/hukin-2014-0047.
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AbstractThe present study aimed to compare players’ tactical behaviour in 3 vs. 3 and 6 vs. 6 soccer small-sided games (SSGs). The sample comprised 3,482 tactical actions performed by 18 U-11 youth soccer players from a Portuguese club, in 3 vs. 3 and 6 vs. 6 SSGs. All participants played eight minutes in both situations and field size was adapted according to the number of players involved (30 m x 19.5 m for 3 vs. 3 and 60 m x 39 m for 6 vs. 6). The System of Tactical Assessment in Soccer (FUT-SAT) was used for data collection and analyses. Descriptive analysis was conducted to verify frequencies and percentages of the variables assessed. The chi-squared (χ2) test was performed to compare the frequencies of the variables between 3 vs. 3 and 6 vs. 6 SSGs and Standardized Residuals (e) were used to examine the influence of the frequency of one or more variables within 3 vs. 3 and 6 vs. 6 SSGs. Data treatment was performed through SPSS for Windows®, version 18.0. Results indicated that players displayed safer behaviours in 6 vs. 6 SSG and more aggressive behaviours in 3 vs. 3 SSG. Findings can aid coaches and teachers to develop different players’ tactical skills according to the chosen SSG (3 vs. 3 or 6 vs. 6) form.
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Jeffries, Matthew D., Travis W. Gannon, James T. Brosnan, and Gregory K. Breeden. "Sprayer Setup Affects Dislodgeable 2,4-D Foliar Residue in Hybrid Bermudagrass Athletic Fields." Weed Technology 31, no. 2 (March 2017): 269–78. http://dx.doi.org/10.1017/wet.2016.22.
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2,4-dimethylamine salt (2,4-D) is a selective broadleaf herbicide commonly applied to turfgrass systems, including athletic fields, which can dislodge from treated vegetation. Building on previous research confirming 2,4-D dislodgeability is affected by management inputs, field research was initiated in 2014 and 2015 in North Carolina and Tennessee to quantify the effects of sprayer setup on dislodgeable 2,4-D foliar residue from hybrid bermudagrass, which is the most common athletic field playing surface in subtropical and tropical climates. More specifically, research evaluated dislodgeable 2,4-D foliar residue following spray applications (2.1 kg ae ha−1) at varying carrier volumes (187, 374, or 748 L ha−1) and nozzles delivering varying droplet sizes (fine=extended range [XR], coarse=drift guard, or extra coarse=air induction extended range [AIXR]). Overall, data suggest minimal 2,4-D dislodge occurs via soccer ball roll (3.6 m) outside the day of application; however, increasing carrier volume and droplet size can further decrease dislodgeable 2,4-D foliar residue. At 2 d after treatment (DAT), 3.87% of applied 2,4-D dislodged when applied at 187 L ha−1compared to 2.05% at 748 L ha−1. Pooled over data from 1 to 6 DAT, 1.59% of applied 2,4-D dislodged following XR nozzle application compared to 1.13% with AIXR nozzle. While these are small numerical differences, dislodgeable residue was measured via one soccer ball roll, which is a repeated process within the sport and the additive effect of sprayer setup treatments can be employed by turfgrass managers to reduce potential human 2,4-D human exposure.
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Morin, Jean-Benoît, George Petrakos, Pedro Jiménez-Reyes, Scott R. Brown, Pierre Samozino, and Matt R. Cross. "Very-Heavy Sled Training for Improving Horizontal-Force Output in Soccer Players." International Journal of Sports Physiology and Performance 12, no. 6 (July 2017): 840–44. http://dx.doi.org/10.1123/ijspp.2016-0444.
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Background:Sprint running acceleration is a key feature of physical performance in team sports, and recent literature shows that the ability to generate large magnitudes of horizontal ground-reaction force and mechanical effectiveness of force application are paramount. The authors tested the hypothesis that very-heavy loaded sled sprint training would induce an improvement in horizontal-force production, via an increased effectiveness of application.Methods:Training-induced changes in sprint performance and mechanical outputs were computed using a field method based on velocity–time data, before and after an 8-wk protocol (16 sessions of 10- × 20-m sprints). Sixteen male amateur soccer players were assigned to either a very-heavy sled (80% body mass sled load) or a control group (unresisted sprints).Results:The main outcome of this pilot study is that very-heavy sled-resisted sprint training, using much greater loads than traditionally recommended, clearly increased maximal horizontal-force production compared with standard unloaded sprint training (effect size of 0.80 vs 0.20 for controls, unclear between-groups difference) and mechanical effectiveness (ie, more horizontally applied force; effect size of 0.95 vs –0.11, moderate between-groups difference). In addition, 5-m and 20-m sprint performance improvements were moderate and small for the very-heavy sled group and small and trivial for the control group, respectively.Practical Applications:This brief report highlights the usefulness of very-heavy sled (80% body mass) training, which may suggest value for practical improvement of mechanical effectiveness and maximal horizontal-force capabilities in soccer players and other team-sport athletes.Results:This study may encourage further research to confirm the usefulness of very-heavy sled in this context.
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Duarte, João P., Manuel J. Coelho-e-Silva, Daniela Costa, Diogo Martinho, Leonardo G. O. Luz, Ricardo Rebelo-Gonçalves, João Valente-dos-Santos, António Figueiredo, André Seabra, and Robert M. Malina. "Repeated Sprint Ability in Youth Soccer Players: Independent and Combined Effects of Relative Age and Biological Maturity." Journal of Human Kinetics 67, no. 1 (July 5, 2019): 209–21. http://dx.doi.org/10.2478/hukin-2018-0090.
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AbstractThe objective of the study was to examine the effects of the relative age effect (RAE) and predicted maturity status on body size and repeated sprint ability (RSA: 7 x 34.2 m / 25 s interval) in youth soccer. The sample was composed of 197 male players aged 13-14 years. Body mass, stature, and sitting height were measured, RSA was assessed in the field, and age at peak height velocity (APHV) was predicted. Factorial ANOVA tested the independent and combined effects of RAE given by birth quarters (BQs) and maturity status on dependent variables. Players born in the second birth quarter (BQ2) were significantly taller (F = 4.28, p < 0.01) than their peers born in BQ1 and BQ3. Additionally, players born in BQ2 performed better than players born in BQ4 in RSA total time and ideal time (F ranged between 4.81 and 4.90, p < 0.01), while players born in BQ1 exhibited a lower RSA fatigue index compared to those born in BQ4 (F = 2.90, p < 0.05). The interaction of the BQ and maturity status was a significant source of inter-individual variation for body size (F ranged between 64.92 and 105.57; p < 0.01) and RSA output (F ranged between 4.082 and 6.76; p < 0.05). In summary, being relatively older and, simultaneously, advanced in maturity status corresponds to a substantial advantage in characteristics that are related to soccer-specific fitness.
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Thomson, Athol, Richard Akenhead, Rodney Whiteley, Pieter D'Hooghe, Ken Van Alsenoy, and Chris Bleakley. "Fifth metatarsal stress fracture in elite male football players: an on-field analysis of plantar loading." BMJ Open Sport & Exercise Medicine 4, no. 1 (June 2018): e000377. http://dx.doi.org/10.1136/bmjsem-2018-000377.
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ObjectiveEvaluate plantar loading during ‘on-field’ common football movements in players after fifth metatarsal (MT-5) stress fracture and compare with matched healthy players.MethodsFourteen elite male soccer players participated in the study conducted on a natural grass playing surface using firm ground football boots. Seven players who had suffered a primary stress fracture (MT-5 group) and seven matched healthy players (controls, CON) performed three common football movements while in-shoe plantar loading data were collected.ResultsLarge between-group differences exist for maximal vertical force normalised to bodyweight (Fmax) at the lateral toes (2-5) of the stance leg during a set-piece kick (MT-5: 0.2±0.06 bodyweight (BW), CON: 0.1±0.05 BW, effect size (ES) 1.4) and the curved run where the MT-5 group showed higher Fmaxwith very large effect size at the lateral forefoot of the injured (closest to curve) limb when running a curve to receive a pass (MT-5 injured−CON=0.01 BW, ES 1.5). Small between-group differences were evident during straight-line running. However, between-limb analysis of MT-5 group showed significant unloading of the lateral forefoot region of the involved foot.ConclusionsElite male football players who have returned to play after MT-5 stress fracture display significantly higher maximum plantar force at the lateral forefoot and lateral toes (2-5) compared with healthy matched control players during two football movements (kick and curved run) with the magnitude of these differences being very large. These findings may have important implications for manipulating regional load during rehabilitation or should a player report lateral forefoot prodromal symptoms.
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KUO, CHUNG-HSIEN, HUNG-CHYUN CHOU, SHOU-WEI CHI, and YU-DE LIEN. "VISION-BASED OBSTACLE AVOIDANCE NAVIGATION WITH AUTONOMOUS HUMANOID ROBOTS FOR STRUCTURED COMPETITION PROBLEMS." International Journal of Humanoid Robotics 10, no. 03 (September 2013): 1350021. http://dx.doi.org/10.1142/s0219843613500217.
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Biped humanoid robots have been developed to successfully perform human-like locomotion. Based on the use of well-developed locomotion control systems, humanoid robots are further expected to achieve high-level intelligence, such as vision-based obstacle avoidance navigation. To provide standard obstacle avoidance navigation problems for autonomous humanoid robot researches, the HuroCup League of Federation of International Robot-Soccer Association (FIRA) and the RoboCup Humanoid League defined the conditions and rules in competitions to evaluate the performance. In this paper, the vision-based obstacle avoidance navigation approaches for humanoid robots were proposed in terms of combining the techniques of visual localization, obstacle map construction and artificial potential field (APF)-based reactive navigations. Moreover, a small-size humanoid robot (HuroEvolutionJR) and an adult-size humanoid robot (HuroEvolutionAD) were used to evaluate the performance of the proposed obstacle avoidance navigation approach. The navigation performance was evaluated with the distance of ground truth trajectory collected from a motion capture system. Finally, the experiment results demonstrated the effectiveness of using vision-based localization and obstacle map construction approaches. Moreover, the APF-based navigation approach was capable of achieving smaller trajectory distance when compared to conventional just-avoiding-nearest-obstacle-rule approach.
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Konzert-Wenzel, J., and H. Bartels. "Terrorist Bomb Explosion at 1980 Oktoberfest in Munich." Prehospital and Disaster Medicine 1, S1 (1985): 346–50. http://dx.doi.org/10.1017/s1049023x00045106.
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On September 26, 1980, at 22:19, a bomb exploded at the main entrance to the Oktoberfest in Munich. The bomb, which had been put together by an apparently politically motivated individual, had planted at waist level in a litter bin. Reconstruction from the fragments found at the site and in the bodies of the victims indicated that the bomb was made from a British mortar projectile, manufactured in 1954, which had been modified to ensure particularly intensive fragmentation. The area affected by the explosion was the size of a soccer field. The effects of the explosion were extremely severe (Figures 1-3): 13 fatalities and approximately 225 nonfatal casualties, of which approximately 50 were severely injured.Thanks to quick, accurate reporting of this major disaster to the Munich Emergency Control Center, which acts as the central coordinating point in case of emergencies, a contingency plan was put into action, which had proved to be effective for disasters involving more than 35 injured. This plan calls for the dispatching of 5 ambulances staffed with physicians, all other available ambulances and the alerting of all hospitals which may have to receive casualties.
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Hernandez-Martin, Antonio, Javier Sanchez-Sanchez, Jose Luis Felipe, Samuel Manzano-Carrasco, Carlos Majano, Leonor Gallardo, and Jorge Garcia-Unanue. "Physical Demands of U10 Players in a 7-a-Side Soccer Tournament Depending on the Playing Position and Level of Opponents in Consecutive Matches Using Global Positioning Systems (GPS)." Sensors 20, no. 23 (December 6, 2020): 6968. http://dx.doi.org/10.3390/s20236968.
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The aim of this study was to analyse the physical demands of U10 players in a 7-a-side-soccer tournament based on the playing positions in 6 consecutive matches by global positioning systems (GPS). Variables of total distance, relative distance in different speed zones, maximum speed, time interval between accelerations, maximum speed acceleration, maximum acceleration, acceleration distance and the number of high-intensity accelerations were analysed. Differences between playing positions were found in the total distance covered by the midfielders. They covered higher total distances than the defenders (+1167 m; 95% CI: 411 to 1922 m; effect size (ES) = 1.41; p < 0.05) and forwards (+1388 m; CI 95%: 712 a 2063 m; TE = 0.85; p < 0.05). The total covered distance increased in the final rounds with respect to the group stage (p < 0.05; ES: 0.44 to 1.62), and high-intensity actions, such as the number of accelerations, were greater in the final rounds compared to the group stage (p < 0.05; ES: 0.44 to 1.62). The physical performance of young football players in a tournament with consecutive matches on a 40 × 62 m football field on the same day is influenced by the playing position and dependent on the level difference between opponents.
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Baker, Camille. "How Big Was the Roman Empire?" Mathematics Teaching in the Middle School 1, no. 9 (March 1996): 754–59. http://dx.doi.org/10.5951/mtms.1.9.0754.
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This activity was designed as part of a sixth-grade interdisciplinary unit. “Seeing the World through the Eyes of Ancient Greeks and Romans.” In addition to learning about Greek and Roman geography, economics, government, and societies in social-studies class. students studied ancient scientists, physicians. and inventors in science class. They also explored Greek and Roman myths, religions, languages, and ideas in language-arts classes. In mathe matics classes, students experimented with the golden ratio and the pentagram. wrote an essay on how the Greeks used mathematics to understand their world, examined Greek and Roman architecture, and investigated the physical size of the Roman Empire. To culminate the unit, students worked in small groups on special projects, such as building a scale model of the Parthenon, measuring and creating a cale drawing comparing the soccer field with the Pantheon, creating and performing original myths or plays depicting life in ancient Greece and Rome, and constructing simple machines or demonstrations of the scientists' work in Greek and Roman times.
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Bachtiar, Mochamad Mobed, Iwan Kurnianto Wibowo, and Rakasiwi Bangun Hamarsudi. "Goalpost Detection Using Omnidirectional Cameras on ERSOW Soccer Robots." Jurnal INFORM 5, no. 2 (August 1, 2020): 86. http://dx.doi.org/10.25139/inform.v0i1.2744.
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The ERSOW robot is a soccer robot developed by Politeknik Elektronika Negeri Surabaya, Indonesia. One important ability of a soccer robot is the ability to find the goal in the field. Goal Post is often used as a sign by soccer robots in a match. The mark is a reference robot in the field to be used in determining the strategy. By knowing the location of the goal in a field, the soccer robot can decide to maneuver in the match to get the right goal kick. There are various methods of detecting goals. One of them is to detect goal posts using vision. In this study, the radial search lines method is used to detect the goalposts as markers. Image input is generated from an omnidirectional camera. The goal area is detected on the front side of the goal area. With experiments from 10 robot position points in the field, only 1 position point cannot detect the goal. The robot cannot detect the goal because what is seen from the camera is the side of the goal, so the front side of the goal area is not visible.
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Dikairono, Rudy, Setiawardhana Setiawardhana, Djoko Purwanto, and Tri Sardjono. "CNN-Based Self Localization Using Visual Modelling of a Gyrocompass Line Mark and Omni-Vision Image for a Wheeled Soccer Robot Application." International Journal of Intelligent Engineering and Systems 13, no. 6 (December 31, 2020): 442–53. http://dx.doi.org/10.22266/ijies2020.1231.39.
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The Convolutional Neural Network (CNN) is an object classification method that has been widely used in recent research. In this paper, we propose CNN for use in the self-localization of wheeled soccer robots on a soccer field. If the soccer field is divided into equally sized quadrants with imaginary vertical and horizontal lines intersecting in the middle of the field, then the soccer field has an identical shape for each quadrant. Every quadrant is a reflection of the other quadrants. Superficially similar images appearing in different positions may result in positioning mistakes. This paper proposes a solution to this problem by using a visual modelling of the gyrocompass line mark and omni-vision image for the CNN-based self-localization system. A gyrocompass is used to obtain the angle of the robot on the soccer field. A 360° omni-vision camera is used to capture images that cover all parts of the soccer field wherever the robot is located. The angle of the robot is added to the omni-vision image using the visual modelling method. The implementation of self-localization without visual modelling gives accuracy rates of 0.3262, and this result is increased to 0.6827 with the proposed methods. The experiment was carried out in the robotics laboratory of the Institut Teknologi Sepuluh Nopember (ITS) with the ITS Robot with Intelligent System (IRIS) robot.
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Golman, Mikhail, Margaret L. Wright, Tony Wong, Thomas Sean Lynch, Christopher S. Ahmad, Stavros Thomopoulos, and Charles A. Popkin. "Partial Patellar Tendon Tears in Athletes: When Is Surgery Required?" Orthopaedic Journal of Sports Medicine 7, no. 7_suppl5 (July 2019): 2325967119S0030. http://dx.doi.org/10.1177/2325967119s00308.
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Objectives: Partial patellar tendon tears (PPTTs) can be a frustrating injury for athletes and physicians. Determining the location and size of the PPTT are fundamental in understanding prognosis and selecting the most effective treatment. With recent enhancements in MRI quality, the size and dimensions of the tear can be more easily and accurately estimated. While some PPTTs respond to therapy, medication, bracing, biologic injections, and/or ultrasound procedures, other PPTTs in do not respond and require surgical intervention. The goal of this study is to correlate PPTT size and location to clinical outcomes, in order to create a classification system to help guide treatment decisions for athletes with PPTT. Methods: 112 athletic patients (range: 15-45 y/o, mean 23.9+7.2 y/o) who underwent knee MRI were included in this study. 85 of those patients (mean 24.9+8.1 y/o) presented with history and physical examination concerning for recalcitrant patellar tendonitis or suspicion of a partial patellar tendon tear. The other 27 athletic patients (mean 25.6+6.3 y/o) underwent MRI for other pathology and were included as age-matched controls. MR scans were evaluated for patellar tendon tear size, thickness, and location with respect to the entire patellar tendon. Descriptive statistics were used to evaluate tendon size and tear distributions. Pearson correlation, univariate regressions, and logistic regression were performed to correlate tendon geometry and tear sizes. Tear geometry variables were compared to patient outcome measures (return to previous activity level, surgical treatment) using t-tests. Results: 56 out of 85 symptomatic patients had partial patellar tendon tears. 91% of PPTTs involved the posterior and posteromedial region of the proximal patellar tendon (Figure 1). On axial MRI imaging, patients with PPTT had mean tendon thickness of 10 mm compared to 5.9 mm for athletes with no PPTT, including healthy controls (p<.0001). There was a significant correlation between patellar tendon thickness and PPTT size (R=0.85, p<0.0001). Logistic regression analysis showed that athletes with patellar tendon thickness above 7.45 mm are likely to have PPTTs (100% sensitivity). Tear distributions according to MRI grading are shown in Table 1. 11 out of 56 patients underwent surgery for PPTT. All 11 of these patients had tear sizes on axial images > 50% of tendon thickness (mean thickness of tear 6.3 mm). Logistic regression showed that patellar tendon thickness > 8.8 mm, and/or tear size > 55% correlated with surgical intervention. Five of the surgical patients did not make a return to sport at the same level. No patient in this series had surgery for tear thickness less than 4.5 mm. Basketball, track and field and soccer were the most common sports involved in the study. Conclusion: PPTTs are located posterior/posteromedially in the proximal patellar tendon. The most sensitive metric for PPTTs are patellar tendon thickness (anterior to posterior), where thickness more than 8.8 mm is strongly predictive of having a partial tear in the tendon. Athletes with greater than a 55% tear thickness on axial MRI imaging or with a tear measuring more than 4.5 mm on axial cuts are less likely to respond to non-operative treatment. Tracking thickness changes on axial views, specifically in the posterior/posteromedial region, may predict effectiveness of non-operative therapy. [Table: see text][Figure: see text]
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Khamdi, Nur, Mochamad Susantok, and Antony Darmawan. "Technique of Standing Up From Prone Position of a Soccer Robot." EMITTER International Journal of Engineering Technology 6, no. 1 (July 10, 2018): 124–36. http://dx.doi.org/10.24003/emitter.v6i1.300.
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One of the humanoid robots being developed in the field of sports is a soccer robot. A soccer robot is a humanoid robot that can perform activities such as playing football. And a variety method fall down of robot soccer such: falling down toward the front direction, side direction, and rear direction. This paper describes the most stands up methods of a soccer robot from its prone position. The proposed method requires only limited movement with degrees of freedom. The movement standing-up of soccer robot has been implemented on the real robot. Tests we performed showed that reliable standing-up from prone position is possible after a fall and such recovery procedures greatly improve the overall robustness of a Soccer Robot.
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Keller, Cary S., Frank R. Noyes, and C. Ralph Buncher. "The Medical Aspects of Soccer Injury Epidemiology." American Journal of Sports Medicine 16, no. 1_suppl (January 1988): S—105—S—112. http://dx.doi.org/10.1177/03635465880160s121.
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In this article, the six major studies of soccer injury epidemiology are reviewed. Strengths and weaknesses of each epidemiologic design are critiqued and the crucial importance of the definition of injury is emphasized. The effect of age, sex, and intensity of play on injury rates is discussed. Our present knowledge of injury rate by anatomical site, player position, and the type of playing surface are reviewed. We examined the importance of player factors such as flexibility, joint laxity, weakness, and incomplete rehabilitation from other injuries. In addition, we reviewed the role played by inadequate equipment, field conditions, and rule violations. A successful program for soccer injury prevention is described, and guidelines for future soccer injury epidemiology research are proposed.
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Cross, Kevin M., Kelly K. Gurka, Susan Saliba, Mark Conaway, and Jay Hertel. "Comparison of Thigh Muscle Strain Occurrence and Injury Patterns Between Male and Female High School Soccer Athletes." Journal of Sport Rehabilitation 27, no. 5 (September 1, 2018): 451–59. http://dx.doi.org/10.1123/jsr.2016-0178.
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Context: Thigh muscle strains are among the most common injuries in high school soccer for both males and females. Similar results have been reported among college soccer players, specifically for hamstring strains. In college soccer, males have a higher injury rate than women, although they share common injury characteristics. Currently, no studies exist comparing the injury rate or injury characteristics of thigh muscle strains between sexes playing high school soccer. Objective: To compare thigh muscle strain injury rates and injury event characteristics among sexes participating in high school soccer. Design: Descriptive epidemiology study. Setting: A total of 100 nationally representative high schools that participated in the High School Sports-Related Injury Surveillance System, Reporting Information Online. Participants: High school soccer athletes who had a thigh muscle strain. Main Outcome Measures: Injury rates of thigh muscle strains were calculated between sexes. The occurrence of the following variables during a thigh muscle injury was compared between sexes: grade level, age, level of play, event type, time of practice, time of competition, basic injury mechanism, soccer activity, player position, field location, practice type, and time of season. Results: Males had a lower injury rate of thigh muscle strains during competition than females (rate ratio = 0.66; 95% confidence interval, 0.47–0.93). No differences between sexes existed in the distribution of first-time or recurrent event characteristics. When combining sexes, recurrent strains (93%) occurred more frequently on the offensive side of the field than first-time strains (59%), P < .001. The majority of strains occurred among the varsity players (71%), during running activities (60%) and practices (58%). Conclusions: Males were less likely to sustain a thigh muscle strain during competitions, but no other differences existed between sexes. The events surrounding all thigh muscle strains may be described with some common properties. Consideration of these characteristics may assist in the development of preventive and rehabilitative programs as well as direct future research on thigh muscle strains among high school soccer players.
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El Rassi, Georges, Masakazu Takemitsu, Patarawan Woratanarat, and Suken A. Shah. "Lumbar Spondylolysis in Pediatric and Adolescent Soccer Players." American Journal of Sports Medicine 33, no. 11 (November 2005): 1688–93. http://dx.doi.org/10.1177/0363546505275645.
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Background Lumbar spondylolysis in young soccer players has not been studied extensively. Purpose The purpose of this study was to review lumbar spondylolysis in young soccer players, describe the causes, and report the results of nonoperative treatment emphasizing the cessation of activity for 3 months. Study Design Case series; Level of evidence, 4. Methods The authors reviewed 57 child and adolescent soccer players (35 boys and 22 girls) with lumbar spondylolysis who came to their outpatient clinic for back pain evaluation. These patients received different modalities of nonoperative treatment, including cessation of sports and wearing a thoracolumbosacral orthosis. Soccer skills, field position, side of dominant leg, age, initiating event of low back pain, duration of symptoms, and nonoperative treatment were reviewed. Clinical outcome of treatment was assessed by the Steiner-Micheli criteria at the most recent follow-up (minimum 2 years). The Fisher exact test was used to compare all the data. Results Of the patients, 43% noticed that pain started after a high-velocity kick. Thirty-three (58%) of 57 patients had excellent results with no pain during sports, 20 (35%) good, 3 (5%) fair, and 1 (2%) poor. Subjects who ceased playing soccer for 3 months had better results than those who did not comply with this restriction. Conclusion The authors recommend stopping sports for at least 3 months in cases of lumbar spondylolysis in young soccer players who hope to return to their previous level of play without back pain.
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Nuccio, Stefano, Luciana Labanca, Jacopo Emanuele Rocchi, Pier Paolo Mariani, Paola Sbriccoli, and Andrea Macaluso. "Altered Knee Laxity and Stiffness in Response to a Soccer Match Simulation in Players Returning to Sport Within 12 Months After Anterior Cruciate Ligament Reconstruction." American Journal of Sports Medicine 49, no. 8 (May 26, 2021): 2150–58. http://dx.doi.org/10.1177/03635465211013020.
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Background: The acute effects of exercise on anterior knee laxity (AKL) and anterior knee stiffness (AKS) have been documented in healthy participants, but only limited evidence has been provided for athletes cleared to return to sports after anterior cruciate ligament (ACL) reconstruction (ACLR). Purpose/Hypothesis: The purpose was to determine if 45 minutes of a soccer match simulation lead to acute changes in AKL and AKS in soccer players returning to sport within 12 months after ACLR. We hypothesized that the reconstructed knee of the ACLR group would exhibit an altered response to sport-specific exercise. Study Design: Controlled laboratory study. Methods: A total of 13 soccer players cleared to return to sport after ACLR and 13 healthy control soccer players matched for age, physical activity level, limb dominance, and anthropometric characteristics were recruited. To assess the effects of a standardized soccer match simulation (Soccer Aerobic Field Test [SAFT45]) on AKL and AKS, an arthrometric evaluation was carried out bilaterally before and immediately after SAFT45. To conduct a comprehensive examination of the force-displacement curve, the absolute and side-to-side difference (SSD) values of both AKL and AKS were extracted at 67, 134, and 200 N. Results: The ACLR and control groups showed similar AKL and AKS at baseline ( P > .05). In response to SAFT45, laxity increased bilaterally at all force levels by 14% to 17% only in the control group ( P < .025). Similarly, AKS at 134 and 200 N decreased in response to SAFT45 only in the control group (10.5% and 20.5%, respectively; P < .025). After SAFT45, the ACLR group had 1.9 and 2.5 times higher SSDs of AKS at 67 and 134 N compared with the control group, respectively ( P < .025), as well as a 1.9 times higher SSD of AKS at 134 N compared with baseline ( P = .014). Conclusion: Soccer players at the time of return to sport after ACLR showed an altered mechanical response to a sport-specific match simulation consisting of bilaterally unchanged AKL and AKS. Clinical Relevance: Soccer players showing altered AKL and AKS in response to exercise after ACLR may not be ready to sustain their preinjury levels of sport, thus potentially increasing the risk of second ACL injuries.
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Zhan, Caizhao, and Jian-Hua Yin. "Field static load tests on drilled shaft founded on or socketed into rock." Canadian Geotechnical Journal 37, no. 6 (December 1, 2000): 1283–94. http://dx.doi.org/10.1139/t00-048.
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The Mass Transit Railway Corporation proposes to construct the Tseung Kwan O Depot (TKD) within Area 86 reclamation at Tseung Kwan O as part of the Tseung Kwan O Extension. The proposed foundation for the TKD comprises about 1000 large-diameter, bored, cast in situ, drilled shafts founded on or socketed into rock. To confirm the design allowable end bearing capacity and rock socket side resistance for the drilled shaft foundations, two test piles were constructed and tested. Both test piles were instrumented with strain gauges and rod extensometers. This paper presents the static compressive load test results on both test piles. The test results indicate that an end bearing capacity of 20.8 MPa (design allowable 7.5 MPa) and rock socket side resistance 2.63 MPa (design allowable 0.75 MPa) are achieved during the pile load tests with no sign of failure.Key words: drilled shaft, static load test, end bearing capacity, rock socket, rock socket side resistance, load transfer.
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이현빈 and 임비오. "The influence of soccer field ground types on lower extremity muscle activation during forward side step." Korean Journal of Sport Science 30, no. 2 (June 2019): 251–57. http://dx.doi.org/10.24985/kjss.2019.118.2.251.
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Chen, Ching Yi, and Chi Chiang Ko. "Designing FIRA Medium-Sized Soccer Robot Vision System Using Particle Swarm Optimization." Applied Mechanics and Materials 764-765 (May 2015): 675–79. http://dx.doi.org/10.4028/www.scientific.net/amm.764-765.675.
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Enabling FIRA medium-sized soccer robots to recognize target objects according to color information requires that competing teams manually set the range of colors according to ambient lighting conditions prior to games. This color information is used to differentiate features of target objects, such as the ball, the goals, and the field. Constructing a color-feature model such as this is extremely time-consuming and the resulting model is unable to adapt dynamically to changes in lighting conditions. This study applied a look-up table method to execute RGB-HSV color space conversion to accelerate video processing. A particle swarm optimization (PSO) scheme was developed to detect the color-feature parameters of the target objects in the HSV color space. This enables the automatic completion of color-feature modeling and the construction of the knowledge model required by the robot for object recognition. Experiment results demonstrate that the proposed method is capable of enhancing the robustness of the robot vision system in determining changes in lighting conditions. In addition, the manpower and time required to set robot parameters prior to games were reduced significantly.
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Armenteros, M., Anto J. Benítez, R. Flores, M. Sillero-Quintana, M. Sánchez Cid, and J. A. Simón. "The training of soccer assistant referees beyond on-field experience: the use of the Interactive Video Test." International Journal of Computer Science in Sport 17, no. 2 (December 1, 2018): 163–74. http://dx.doi.org/10.2478/ijcss-2018-0009.
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Abstract The main objective of this article was to analyse whether the Interactive Video Test (IVT) is a useful tool for the practical off-field training of soccer assistant referees, and if its use could reduce erroneous on-field decisions when applying Law 11 of the Laws of the Game. Assistant referees were taken from the Spanish 2nd “B” and 3rd Divisions, and were divided into two groups, the Experimental Group (EG) and the Control Group (CG). The referees in the EG were trained with the Interactive Video Test by analysing 720 off-side decisions. Subsequently, both groups were assessed in on-field tests involving the simulation of 326 possible off-side situations. When the results of both groups were compared, there was a continuous improvement over time in the EG associated to the use of the IVT, significantly better than the improvement of the CG. Moreover, the IVT proved to be a good diagnostic tool to assess the skills of assistant referees in perceiving and evaluating off-side situations.
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Kurz, Eduard, René Schwesig, Stefan Pröger, Kay Brehme, Karl-Stefan Delank, and Thomas Bartels. "Judging return-to-sport after ACL reconstruction using acyclic as well as cyclic neuromuscular performance tests." Orthopaedic Journal of Sports Medicine 8, no. 5_suppl4 (May 1, 2020): 2325967120S0032. http://dx.doi.org/10.1177/2325967120s00325.
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Aims and Objectives: Most athletes expect to return to their pre-injury sport without restrictions after a reconstruction of their torn anterior cruciate ligament (ACLR). Different indicators for a safe and successful return to sport have been identified. Very recent results revealed that indicators of absolute performance were superior to e.g. limb symmetry. Thus, the primary aim of this investigation was to compare neuromuscular performance of athletes returned to sport after ACLR with uninjured athletes. The secondary aim was to relate overall performance to symmetry in both groups. Materials and Methods: Eighty-four athletes (age: 24 (SD 5) years; 21 women; handball: 33, soccer: 25, volleyball: 15, ice hockey: 5, track and field: 3, judo: 2, swimming: 1) participated in this cross-sectional design. The sample consisted of 17 patients after primary ACL reconstruction (ACLR, 5 women) eleven (6-23) months after return to sport clearance. Participants performed acyclic as well as cyclic neuromuscular tests on a SpeedCourt device (GlobalSpeed GmbH). Unilaterally performed squat jump (SJ) and drop jump (DJ) heights were measured as an indicator of lower extremity explosive or reactive strength under acyclic concentric or fast stretch-shortening muscle action conditions, respectively. The 15 s vertical foot tapping (FT) test was applied to measure cyclic lower extremity performance. The results of each test were converted into z-scores. Z-scores indicate how many standard deviations an individual’s score is away from the mean. Accordingly, a z-score of zero equals the sample’s mean. Athlete’s z-scores were summed up, resulting in the performance score (PS) which indicates overall performance. The participants were ranked based on their PS. Further, for the unilaterally performed tests (SJ, DJ) limb symmetry indices (LSIs) were calculated by dividing the smaller by the larger value and multiplying by 100. LSIs were related to the PS separately for the whole sample as well as for the ACLR subgroup. Effect size is given as Cohen’s d. Results: Uninjured athletes revealed higher values for the PS (t(82) = 3.5, p < 0.001; d > 0.9) and for the LSIs (t(82) > 5.1, p < 0.001; d > 1.4) as compared to ACLR athletes. For the subgroup of uninjured athletes, no significant relationship was found between the overall performance and the LSIs (SJ: r = -0.2, p = 0.15; DJ: r = -0.1, p = 0.43) as well as within both LSIs (r = 0.1, p = 0.41). In athletes after ACLR, in contrast, the LSIs between SJ and DJ showed a strong and significant association (r > 0.73, p < 0.001). Interestingly, neither the overall performance nor the LSIs could be related to the time after injury (0.17 < r < 0.37, p > 0.14). Conclusion: Based on the tests utilized in this study, the ACLR athletes underperformed the uninjured group. Independent from time since injury or surgery, function was not reestablished. Results of functional tests should be an integrative part of the return-to-sport decision process.
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Mangan, John J., Ryan Rogero, Daniel J. Fuchs, and Steven M. Raikin. "Surgical Management of Chronic Exertional Compartment Syndrome of the Lower Extremity: Outcome Analysis and Return to Sport." Foot & Ankle Orthopaedics 4, no. 4 (October 1, 2019): 2473011419S0005. http://dx.doi.org/10.1177/2473011419s00053.
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Category: Sports Introduction/Purpose: Chronic exertional compartment syndrome (CECS) occurs as the result of increasing pressure in a closed muscular compartment, typically in the leg, as the result of repetitive activity. Physiologic changes in myofibril size during exercise increase muscle volume leading to higher compartmental pressures, which can result in neurologic and vascular changes. CECS has been estimated to cause 27%-33% of exertional leg pain and frequently leads to a decrease in athletic training and competition. CECS affects males and females equally but is especially common in young athletes, particularly competitive runners, as well as soccer, field hockey and lacrosse players and in military personnel. The purpose of this study is to evaluate patient- reported outcomes and return to sport (RTS) after open fasciotomy for lower extremity CECS. Methods: A retrospective review of patients that underwent lower extremity fasciotomy for CECS by a single surgeon was performed. All patients had a diagnosis confirmed by pre- and post-exercise compartment pressure testing. Two-incision technique was used with lateral and anterior compartments released through a lateral incision, while deep and superficial posterior compartments were released through a medial approach when indicated. Patients that underwent a fasciotomy for trauma, infection, or an acute pathologic process were excluded. Patient outcome measures were recorded for each patient including the Foot and Ankle Ability Measure-Sport subscale (FAAM-Sport), FAAM-Sport Single Assessment Numeric Evaluation (SANE), and Visual Analog Scale (VAS) for pain. A novel RTS questionnaire was designed and implemented. Patient demographic information was included. Outcome analysis was performed using Student’s t-test and chi-square testing. RTS was compared using Mann-Whitney U testing, and regression analysis was used to identify independent risk factors for failure to RTS. Results: 59 patients that underwent 63 procedures were included. Average age was 26.6 years (range, 15-55), 59.3% were female, and average follow-up was 58.8 months (range, 12-115). 37 patients underwent simultaneous bilateral fasciotomies, 8 had staged bilateral fasciotomies and 18 underwent unilateral fasciotomy. Four-compartment fasciotomy was performed 14 times and 49 fasciotomies involved one or two compartments. Significant postoperative improvement was seen in the FAAM-Sport, Sport SANE and the VAS for pain compared to preoperative scores (p<0.001). Overall 93.2% (55/59) of patients were able to return to sport, 78.1% (43/55) returned to the same level of sport, and 21.9% (12/54) returned to a lower level of competition. Bivariate regression analysis demonstrated that higher preoperative BMI (p=0.049) was associated with a lower likelihood of return to sport. Conclusion: CECS is a relatively common problem seen in young athletes and can cause significant change in athletic participation and ability. This cohort of patients who underwent lower extremity fasciotomies for CECS is larger than any previously published. This study demonstrates that lower extremity fasciotomy for CECS results in improvement of patient-reported outcomes and returns athletes back to competition at a high rate.
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Esser, Stephan, David Jantz, Mark F. Hurdle, and Walter Taylor. "Proximal Rectus Femoris Avulsion: Ultrasonic Diagnosis and Nonoperative Management." Journal of Athletic Training 50, no. 7 (July 1, 2015): 778–80. http://dx.doi.org/10.4085/1052-6050-50.2.13.
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Objective To present a case of ultrasonic diagnosis and nonoperative management of a complete proximal rectus femoris avulsion in a National Collegiate Athletic Association Division 1 soccer goalkeeper. Background While delivering a goal kick, a previously uninjured 24-year-old collegiate soccer goalkeeper had the sudden onset of right anterior thigh pain. He underwent rehabilitation with rapid resolution of his presenting pain but frequent intermittent recurrence of anterior thigh pain. After he was provided a definitive diagnosis with musculoskeletal ultrasound, he underwent an extended period of rehabilitation and eventually experienced complete recovery without recurrence. Differential Diagnosis Rectus femoris avulsion, rectus femoris strain or partial tear, inguinal hernia, or acetabular labral tear. Treatment Operative and nonoperative options were discussed. In view of the player's recovery, nonoperative options were pursued with a good result. Uniqueness Complete proximal rectus femoris avulsions are rare. Our case contributes to the debate on whether elite-level kicking and running athletes can return to full on-field performance without surgery. Conclusions Complete proximal rectus femoris avulsions can be treated effectively using nonoperative measures with good preservation of function even in the elite-level athlete. In addition, musculoskeletal ultrasound is an excellent tool for on-site evaluation and may help guide prognosis and management.
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Asem, Pouyan, and Paolo Gardoni. "Evaluation of peak side resistance for rock socketed shafts in weak sedimentary rock from an extensive database of published field load tests: a limit state approach." Canadian Geotechnical Journal 56, no. 12 (December 2019): 1816–31. http://dx.doi.org/10.1139/cgj-2018-0590.
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This paper presents analyses of the measured peak side resistance of rock sockets constructed in weak claystone, shale, limestone, siltstone, and sandstone. The peak side resistance is obtained from in situ axial load tests on drilled shafts, anchors, and plugs. The parameters that affect the development of peak side resistance are determined using in situ load test data. It is found that peak side resistance increases with the unconfined compressive strength and deformation modulus of the weak rock, and decreases with the increase in length of the shear surface along the rock socket sidewalls. The increase in socket diameter also slightly decreases the peak side resistance. Additionally, it is found that the initial normal stresses do not significantly affect the measured peak side resistance in the in situ load tests. The in situ load test data are used to develop an empirical design equation for determination of the peak side resistance. The proposed model for peak side resistance and the reliability analysis are used to determine the corresponding resistance factors for use in the load and resistance factor design framework for assessment of the strength limit state.
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VELOSO, MANUELA, NICHOLAS ARMSTRONG-CREWS, SONIA CHERNOVA, ELISABETH CRAWFORD, COLIN MCMILLEN, MAAYAN ROTH, DOUGLAS VAIL, and STEFAN ZICKLER. "A TEAM OF HUMANOID GAME COMMENTATORS." International Journal of Humanoid Robotics 05, no. 03 (September 2008): 457–80. http://dx.doi.org/10.1142/s0219843608001479.
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We present a team of two humanoid robot commentators for AIBO robot soccer games. The two humanoids stand by the side lines of the playing field, autonomously observe the game, wirelessly listen to a "game controller" computer, recognize events, and select announcing actions that may require coordination with each other. Given the large degree of uncertainty and dynamics of the robot soccer games, we further introduce a "Puppet Master" control that allows humans to intervene, prompting the robots to commentate an event if previously undefined or undetected. The robots recognize events based on input from these three sources, namely own and shared vision, game controller, and occasional Puppet Master. We present the two-humanoid behavioral architecture and the vision-based event recognition, including a SIFT-based vision processing algorithm that allows for the detection of multiple similar objects, such as the identical shaped robot players. We introduce the commentating algorithm that probabilistically selects a commentating action from a set of weighted actions corresponding to a detected event. The probabilistic selection uses the game history and updates the action weights to effectively avoid repetition of comments to enable entertainment. Our work, corresponding to a fully implemented system, CMCast, with two QRIO robots, contributes a team of two humanoids fully executing a challenging observation, modeling, coordination, and reporting task.
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Rong-Yu, Li, and Brian Jones. "New brachiopod genera from Bird Fiord Formation (Devonian), arctic Canada." Journal of Paleontology 76, no. 4 (July 2002): 648–58. http://dx.doi.org/10.1017/s0022336000041925.
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Brachiopods are common in the lower part of the late Early to Middle Devonian Bird Fiord Formation that is a carbonate-clastic transition succession found in Arctic Canada. These brachiopods, which lived in a shallow, near-shore, marine environment, includes three new genera: Borealistrophia, Arcticastrophia, and Grinnellathyis. The strophomenid Borealistrophia, which is characterized by two pairs of straight side septa, prominent and thick socket ridges, a thick but short median septum, and a cordate ventral muscle field, is found in the Baad Fiord, Blubber Point, and Norwegian members on Bathurst, Devon, North Kent, and Ellesmere islands. The strophomenid Arcticastrophia, which is distinctive because of its stout transmuscle septa, its narrow and low medium septum, and elevated ventral muscle field, is found in the Baad Fiord Member on Bathurst and Devon islands. The athyridid Grinnellathyris, which is characterized by an imperforated cardinal plate and inverted U-shaped jugum, is found in the Baad Fiord Member on Bathurst, North Kent, and Devon islands. The similarities between Grinnellathyris and Johnsonathyris Savage, Eberlein, and Churkin, 1978, in terms of their shell size and internal structures, may indicate that the latter evolved from the former.
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Choi, Hee Dong, Myung Bo Hong, and Hyun Min Kang. "Media Exposure and Audiences` Recall for the Sponsor Brands on the Different Types of Field-side Advertising Board in Professional Soccer Stadiums." Journal of Sport and Leisure Studies 34 (November 30, 2008): 203–13. http://dx.doi.org/10.51979/kssls.2008.11.34.203.
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Maujud, Muhammad Fajri, Zainal Afandi, and Budiman Agung Pratama. "The Increase in VO2 Max and Passing Using Exercise Small-Sided Game 3 vs 3 and 6 vs 6 On Football Players." COMPETITOR: Jurnal Pendidikan Kepelatihan Olahraga 13, no. 2 (June 22, 2021): 216. http://dx.doi.org/10.26858/cjpko.v13i2.21602.
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The purpose of this study was to determine the increase in vo2max and passing skills using small-sided games 3 vs 3 and 6 vs 6 exercises in soccer players. This study uses a quantitative approach, the type of research is experimental research, the sample used is 51 football players in Trenggalek under-14 who were selected randomly, this research was carried out in Trenggalek district, namely the Siwalan field, Sumbergedong field, and Sumberagung field, the instrument in the study This study uses a multistage fitness test and a passing test in football, data analysis uses the Manova test. The results showed that there was a difference between the small-sided games 3 vs 3 exercise group and the 6 vs 6 small-sided games group to increase vo2max with a sig value. 0.031 < 0.05, and there is a difference between the small-sided games 3 vs 3 practice group and the 6 vs 6 small-sided games group to improve passing with a sig value of 0.027 < 0.05. It can be concluded that overall small-side game exercises 3 vs 3 and 6 vs 6 can increase vo2max and passing for football players.
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Dai, Guo Liang, Abdellatif Boucheloukh, and Wei Ming Gong. "Review of Design Methods of the Ultimate Side Shear and Base Resistance for Rock-Socketed Pile." Applied Mechanics and Materials 353-356 (August 2013): 60–67. http://dx.doi.org/10.4028/www.scientific.net/amm.353-356.60.
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To determine the ultimate load capacity of drilled shaft socketed into rock under axial compression loading, it is necessary to predict both the ultimate side shear resistance and the base resistance based on field load test or/ and laboratory tests. In geotechnical engineering there are several methods proposed the relationship between rock properties (the unconfined compressive strength) and the ultimate side shears resistance and base resistance. This paper presents the review of design methods of ultimate side shear and base resistance for rock-socketed pile. These empirical functions depend on the socket type and the range of the unconfined compressive strength of rock.
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Petersson, Maria. "Ancient Fields Excavated." European Journal of Archaeology 2, no. 1 (1999): 57–76. http://dx.doi.org/10.1179/eja.1999.2.1.57.
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In this paper, I discuss the importance of fossil fields and traces of ancient agriculture as archaeological source material. Examples from excavations in the Väderstad area in Östergötland, Sweden are given. In the article, I describe and contrast two different methods of excavation: (A) The digging of long trenches through visible features, a method here used as a means of trial excavation but previously often the only method used in the excavation of ancient fields. This method gives at the best a framework for interpretation. Though it does enable dating, the intensity, extent and content of different phases cannot be established with any degree of certainty. (B) The removal of the ancient plough soil over the full extent of the ancient field, a method here used for final excavations. With this method, enough information was acquired for the derivation of a detailed interpretation. The results will be detailed enough to allow comparison of the excavated fields with other categories of excavated monuments and thus give a new perspective on general archaeological problems. The RAÄ 166 site at Hogstads socken is given as an example of this approach.
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Bosch, Saskia, Pierre Viviers, Wayne Derman, and Richard De Villiers. "A “scattered” SCAT in a football goalkeeper: a case report." South African Journal of Sports Medicine 32, no. 1 (March 5, 2020): 3. http://dx.doi.org/10.17159/2078-516x/2020/v32i1a7737.
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Background: In an acute field-side setting, it is often challenging to differentiate benign sports-related concussion (SRC) from potential, more sinister, intracranial pathology. Moreover, recovery in the ensuing days and weeks is often complex as the resolution of classical signs and symptoms does not always follow a standard pattern.
Aim: To highlight the value of a structured and repeated thorough clinical assessment approach toward SRC, particularly as atypical and unexpected sequences in patient recovery patterns may require further specialist referral and intervention.
Findings: A football goalkeeper sustained a concussion in which symptoms failed to resolve as expected. Deterioration in his clinical condition led to an eventual diagnosis of Chiari malformation (type I), which required surgical intervention.Implications: Non-typical recovery patterns of concussion may be indicative of increased severity when considered retrospectively. However, clinicians should not discount the possibility of underlying conditions.
Keywords: concussion, soccer, sports-related head injury
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Antoniou, Vyron, and Chryssy Potsiou. "A Deep Learning Method to Accelerate the Disaster Response Process." Remote Sensing 12, no. 3 (February 6, 2020): 544. http://dx.doi.org/10.3390/rs12030544.
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This paper presents an end-to-end methodology that can be used in the disaster response process. The core element of the proposed method is a deep learning process which enables a helicopter landing site analysis through the identification of soccer fields. The method trains a deep learning autoencoder with the help of volunteered geographic information and satellite images. The process is mostly automated, it was developed to be applied in a time- and resource-constrained environment and keeps the human factor in the loop in order to control the final decisions. We show that through this process the cognitive load (CL) for an expert image analyst will be reduced by 70%, while the process will successfully identify 85.6% of the potential landing sites. We conclude that the suggested methodology can be used as part of a disaster response process.
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Begum, Fahima A., Babar Kayani, Justin S. Chang, Rosamond J. Tansey, and Fares S. Haddad. "The management of proximal rectus femoris avulsion injuries." EFORT Open Reviews 5, no. 11 (November 2020): 828–34. http://dx.doi.org/10.1302/2058-5241.5.200055.
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Injuries to the quadriceps muscle group are commonly seen in sporting activities that involve repetitive kicking and high-speed sprinting, including football (soccer), rugby and athletics. The proximal rectus femoris is prone to avulsion injuries as rapid eccentric muscle contraction leads to asynchronous muscle activation and different force vectors through the straight and reflected heads. Risk factors for injury include previous rectus femoris muscle or hamstring injury, reduced flexibility of the quadriceps complex, injury to the dominant leg, and dry field playing conditions. Magnetic resonance imaging (MRI) is the preferred imaging modality as it enables the site of injury to be accurately located, concurrent injuries to be identified, preoperative grading of the injury, and aids surgical planning. Non-operative management is associated with highly variable periods of convalescence, poor return to preinjury level of function and high risk of injury recurrence. Operative treatment of proximal rectus femoris avulsion injuries with surgical repair or surgical tenodesis enables return to preinjury level of sporting activity and high functional outcomes. Surgical tenodesis of proximal rectus femoris avulsion injuries may offer an avenue for further reducing recurrence rates compared to direct suture anchor repair of these injuries. Cite this article: EFORT Open Rev 2020;5:828-834. DOI: 10.1302/2058-5241.5.200055
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INTARA, YAZID ISMI, ABIMANYU DIPO NUSANTARA, SUPANJANI SUPANJANI, ZULBAHRUM ZULBAHRUM CANIAGO, and RISKA EKAWITA. "Spatial patterns of evapotranspiration distribution in palm oil plantation." Nusantara Bioscience 11, no. 1 (January 18, 2019): 1–7. http://dx.doi.org/10.13057/nusbiosci/n110101.
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Intara YI, Nusantara AD, Supanjani, Caniago Z, Ekawita R. 2019. Spatial patterns of evapotranspiration distribution in palm oil plantation. Nusantara Bioscience 11: 1-7. Evapotranspiration can directly calculate by some climatic factors which are processed in the form of simulation modeling of two-dimensional evaporation distribution on specified coordinates. This research had been conducted in palm oil plantation PT. Bio Nusantara Bengkulu, Indonesia. The sampling location covered some areas named as TM2, TM22, Palm oil-Field, Palm oil-Residential Area and Palm oil-Secondary Forest. The TM2 and TM22 were a location of palm oil plantation used for 2 and 22 years planting respectively. The three remaining locations dedicated to areas of which mix TM22 with soccer Field, Residential Area and Secondary Forest. The results showed that in palm oil plantation TM 2 which consisted of herbaceous plants and bushes produced more water vapor. At palm oil plantation TM 22 which had fully developed canopy or the entire soil area had been covered by canopy, so only transpiration occurred at this site, less water vapor was produced. This is due to the temperature condition is inversely proportional to the relative humidity. As a comparison of a palm oil plantation evapotranspiration measurement result, indicated on area of football field where only has grass in the field, with low intensity of light, wind, and humidity, affected directly to high amount of evapotranspiration, therefore, more water vapor produced. The measurement result of palm oil plantation nearby residential area showed that the area which consisted of herbaceous plants and bushes, also zinc-roofed residential with the intensity of light and wind directly hit the area, produced less water vapor. Moreover, the condition at the border area between TM 22 and the palm oil secondary forest contained mixed plantation. The measurement result showed that the palm oil secondary forest had the same height of canopy and almost had equal humidity (>76%), but secondary forest plants had more dense plantation density which produced less water vapor.