The Relationship between Softball Student-Athletes\u27 Motivation, Self-Confidence, and Perception of Coach Leadership

This study advanced the understanding of relationships among coach leadership and collegiate softball players\u27 self-confidence and motivation. The purpose of this study was to examine if there was a correlation between perceived coach leadership and softball player\u27s self-confidence and motivation. Ninety-seven U.S. collegiate female softball student-athletes completed a Basic Demographic Survey, the Trait Sport-Confident Inventory (TSCI), Leadership Scale for Sport (LSS), and Sport Motivation Scale (SMS). Multiple linear regression analyses results indicated that LSS and SMS subscales explained 45 percent of the variance in TSCI scores. Pearson correlation coefficients were computed and significant moderate positive relationships were found between the LSS subscales, SMS subscales, and TSCI scores. These results indicate that there is a relationship between perceived coach leadership and a softball student-athlete\u27s self-confidence and motivation. The research findings can be used to aid coaches in developing a coaching style that is well perceived by softball athletes. This will assist coaches in developing techniques (i.e., communication skills, motivational factors, correctional feedback, mental toughness) that will motivate and give their softball athletes high levels of self-confidence while performing

The Relationship between Softball Student-Athletes\u27 Motivation, Self-Confidence, and Perception of Coach Leadership

This study advanced the understanding of relationships among coach leadership and collegiate softball players\u27 self-confidence and motivation. The purpose of this study was to examine if there was a correlation between perceived coach leadership and softball player\u27s self-confidence and motivation. Ninety-seven U.S. collegiate female softball student-athletes completed a Basic Demographic Survey, the Trait Sport-Confident Inventory (TSCI), Leadership Scale for Sport (LSS), and Sport Motivation Scale (SMS). Multiple linear regression analyses results indicated that LSS and SMS subscales explained 45 percent of the variance in TSCI scores. Pearson correlation coefficients were computed and significant moderate positive relationships were found between the LSS subscales, SMS subscales, and TSCI scores. These results indicate that there is a relationship between perceived coach leadership and a softball student-athlete\u27s self-confidence and motivation. The research findings can be used to aid coaches in developing a coaching style that is well perceived by softball athletes. This will assist coaches in developing techniques (i.e., communication skills, motivational factors, correctional feedback, mental toughness) that will motivate and give their softball athletes high levels of self-confidence while performing

Shear strength development of the phenol–formaldehyde adhesive bond during cure

The development of the shear strength of the phenol-formaldehyde (PF) adhesive bond during curing was investigated. Five different PF adhesive mixtures and 1.1 mm thick peeled beech (Fagus sylvatica L.) veneer were used to produce lap-shear specimens, which were cured at a pressing temperature of 160°C. Dielectric analysis (DEA) and modified ABES (automated bonding evaluation system) were used to evaluate the physical-chemical and mechanical aspects of PF adhesive cure in a miniature hot-press. The degree of cure, which was calculated from conductivity data, was dependent on pressing time and the composition of the PF adhesive. An addition of rye flour to the PF adhesive significantly postponed the curing process as determined by DEA. It was found that the adhesive bond started to develop in the last stage of the curing (vitrification), by which time most of the physical-chemical conversion of the adhesive had been completed

Effect of Thermal Modification of Spruce Wood on Nails Embedment Strength

Nails represent the easiest and most common method to connect timber members, but, since joints and connections frequently represent the weakest points in timber structures, they need special attention. The embedment strength of nails is one of the important properties of construction wood, since it determines the joint’s strength and required size and the number of nails used in the connection. The embedment strength of nails in spruce wood thermally modified at different temperatures (170, 190, 210, and 230°C) was measured. Nail embedment strength was determined according to EN 7383:2007 Timber Structures – Test methods – Determination of embedment strength and foundation values for dowel-type fasteners. The embedment strength was tested for nails, without pre-bored holes, in three ways: compression parallel to grain, tension parallel to grain and compression perpendicular to grain. The research showed that the embedment strength of nails slightly decreased with the temperature of the thermal treatment of wood, but the statistically significant differences were only between control samples and the most modified samples. The average nail embedment strength decreased with thermal modification at 230°C by 18% (compression parallel to the grain), 34% (compression perpendicular to the grain) and 33% (tension parallel to the grain). The highest decreases were recorded in nail embedment strength measured in compression perpendicular to the grain. This trend had been expected, since wood loses its strength with thermal modification. The measurements showed that thermally modified spruce has lower embedment strength and thus joints with nails need to be constructed differently and with a larger number of nails and larger spacing, in order to achieve the required strength comparable to non-modified wood

Quantitative characterization of chemical degradation of heat-treated wood surfaces during artificial weathering using XPS

The X‐ray photoelectron spectroscopy (XPS) study of three heat‐treated North American wood species (jack pine, birch and aspen) was carried out to evaluate chemical modifications occurring on the wood surface during artificial weathering for different times. The results suggest that the weathering reduces lignin content (aromatic rings) at the surface of heat‐treated wood, consequently, the carbohydrates content increases. This results in surfaces richer in cellulose and poorer in lignin. Heat‐treated wood surfaces become acidic due to weathering, and the acidity increases as the weathering time increases. Three possible reasons are given to account for the increase of acidity during weathering. The lignin content increases, whereas the hemicelluloses content decrease due to heat treatment. Heat‐treated woods have lower acidity to basicity ratios than the corresponding untreated woods for all three species because of the decrease in carboxylic acid functions mainly present in hemicelluloses. The wood composition changes induced by weathering are more significant compared to those induced by heat treatment at wood surface. Exposure to higher temperatures causes more degradation of hemicelluloses, and this characteristic is maintained during weathering. However, the wood direction has more effect on chemical composition modification during weathering compared to that of heat treatment temperature. The heat‐treated jack pine is affected most by weathering followed by heat‐treated aspen and birch. This is related to differences in content and structure of lignin of softwood and hardwood. The use of XPS technique has proved to be a reliable method for wood surface studies

Microwave sensor system for continuous monitoring of adhesive curing processes

A microwave sensor system has been developed for monitoring adhesive curing processes. The system provides continuous, real-time information about the curing progress without interfering with the reaction. An open-coaxial resonator is used as the sensor head, and measurements of its resonance frequency and quality factor are performed during cure to follow the reaction progress. Additionally, the system provides other interesting parameters such as reaction rate or cure time. The adhesive dielectric properties can also be computed off-line, which gives additional information about the process. The results given by the system correlate very well with conventional measurement techniques such as differential scanning calorimetry, combining accuracy and rate with simplicity and an affordable cost. © 2012 IOP Publishing Ltd.The authors thank Rut Benavente Martinez for her assistance in the DSC experiments. 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