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

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. The contract of BG-B is financed by the Ministry of Science and Innovation of Spain, through the 'Torres Quevedo' Sub-programme, which is also co-financed by the European Social Fund (ESF). This work has been financed by the Ministry of Science and Innovation of Spain through the project MONIDIEL (TEC2008-04109).García Baños, B.; Catalá Civera, JM.; Penaranda-Foix, FL.; Canós Marín, AJ.; Sahuquillo Navarro, O. (2012). Microwave sensor system for continuous monitoring of adhesive curing processes. Measurement Science and Technology. 23(3). https://doi.org/10.1088/0957-0233/23/3/035101S233Jost, M., & Sernek, M. (2008). Shear strength development of the phenol–formaldehyde adhesive bond during cure. Wood Science and Technology, 43(1-2), 153-166. doi:10.1007/s00226-008-0217-2Costa, M. L., Botelho, E. C., Paiva, J. M. F. de, & Rezende, M. C. (2005). Characterization of cure of carbon/epoxy prepreg used in aerospace field. Materials Research, 8(3), 317-322. doi:10.1590/s1516-14392005000300016Chen, J., & Hojjati, M. (2007). Microdielectric analysis and curing kinetics of an epoxy resin system. Polymer Engineering & Science, 47(2), 150-158. doi:10.1002/pen.20687Sernek, M., & Kamke, F. A. (2007). Application of dielectric analysis for monitoring the cure process of phenol formaldehyde adhesive. International Journal of Adhesion and Adhesives, 27(7), 562-567. doi:10.1016/j.ijadhadh.2006.10.004Núñez, L., Gómez-Barreiro, S., Gracia-Fernández, C. A., & Núñez, M. R. (2004). Use of the dielectric analysis to complement previous thermoanalytical studies on the system diglycidyl ether of bisphenol A/1,2 diamine cyclohexane. Polymer, 45(4), 1167-1175. doi:10.1016/j.polymer.2003.12.024Lefebvre, D. R., Han, J., Lipari, J. M., Long, M. A., McSwain, R. L., & Wells, H. C. (2006). Dielectric analysis for in-situ monitoring of gelatin renaturation and crosslinking. Journal of Applied Polymer Science, 101(5), 2765-2775. doi:10.1002/app.21631Cordovez, M., Li, Y., & Karbhari, V. M. (2004). Assessment of Dielectrometry for Characterization of Processing and Moisture Absorption in FRP Composites. Journal of Reinforced Plastics and Composites, 23(4), 445-456. doi:10.1177/0731684404031980Das, N. K., Voda, S. M., & Pozar, D. M. (1987). Two Methods for the Measurement of Substrate Dielectric Constant. IEEE Transactions on Microwave Theory and Techniques, 35(7), 636-642. doi:10.1109/tmtt.1987.1133722Fioretto, D., Livi, A., Rolla, P. A., Socino, G., & Verdini, L. (1994). The dynamics of poly(n-butyl acrylate) above the glass transition. Journal of Physics: Condensed Matter, 6(28), 5295-5302. doi:10.1088/0953-8984/6/28/007Givot, B. L., Krupka, J., & Belete, D. Y. (s. f.). Split post dielectric resonator technique for dielectric cure monitoring of structural adhesives. 13th International Conference on Microwaves, Radar and Wireless Communications. MIKON - 2000. Conference Proceedings (IEEE Cat. No.00EX428). doi:10.1109/mikon.2000.913931Canos, A. J., Catala-Civera, J. M., Penaranda-Foix, F. L., & Reyes-Davo, E. (2006). A novel technique for deembedding the unloaded resonance frequency from measurements of microwave cavities. IEEE Transactions on Microwave Theory and Techniques, 54(8), 3407-3416. doi:10.1109/tmtt.2006.877833Marks, R. B., & Williams, D. F. (1992). A general waveguide circuit theory. Journal of Research of the National Institute of Standards and Technology, 97(5), 533. doi:10.6028/jres.097.024Harrington, R. F. (1967). Matrix methods for field problems. Proceedings of the IEEE, 55(2), 136-149. doi:10.1109/proc.1967.5433Baker-Jarvis, J., Janezic, M. D., Domich, P. D., & Geyer, R. G. (1994). Analysis of an open-ended coaxial probe with lift-off for nondestructive testing. IEEE Transactions on Instrumentation and Measurement, 43(5), 711-718. doi:10.1109/19.328897Taylor, B. N. (1994). Guidelines for evaluating and expressing the uncertainty of NIST measurement results. doi:10.6028/nist.tn.1297Casalini, R., Corezzi, S., Livi, A., Levita, G., & Rolla, P. A. (1997). Dielectric parameters to monitor the crosslink of epoxy resins. Journal of Applied Polymer Science, 65(1), 17-25. doi:10.1002/(sici)1097-4628(19970705)65:13.0.co;2-tPreu, H., & Mengel, M. (2007). Experimental and theoretical study of a fast curing adhesive. International Journal of Adhesion and Adhesives, 27(4), 330-337. doi:10.1016/j.ijadhadh.2006.06.004Harper, D. P., Wolcott, M. P., & Rials, T. G. (2001). Evaluation of the cure kinetics of the wood/pMDI bondline. International Journal of Adhesion and Adhesives, 21(2), 137-144. doi:10.1016/s0143-7496(00)00045-2Garcia-Banos, B., Canos, A. J., Penaranda-Foix, F. L., & Catala-Civera, J. M. (2011). Noninvasive Monitoring of Polymer Curing Reactions by Dielectrometry. IEEE Sensors Journal, 11(1), 62-70. doi:10.1109/jsen.2010.2050475He, Y. (2001). DSC and DEA studies of underfill curing kinetics. Thermochimica Acta, 367-368, 101-106. doi:10.1016/s0040-6031(00)00654-7Núñez-Regueira, L., Gracia-Fernández, C. A., & Gómez-Barreiro, S. (2005). Use of rheology, dielectric analysis and differential scanning calorimetry for gel time determination of a thermoset. Polymer, 46(16), 5979-5985. doi:10.1016/j.polymer.2005.05.06

Porównanie wytrzymałości połączeń w ościeżnicach okiennych

The strength of joints with a wooden ring, which are protected by international patent was compared with the strength of tenon and dowel joints, and consequently the applicability and suitability for producing such window frames was established. The strength of different implementations of angular joints of window profiles was tested on a tensile-testing machine. It was established that the average ultimate strength of joints with a wooden ring was higher than the ultimate strength of tenon joints, which was chosen as an upper reference limit.Połączenia na czop są typowym przykładem zastosowania belek kątowych w ościeżnicach okiennych. Wytrzymałość ościeżnicy okiennej zależy także od lepiszcza i powierzchni, na którą je naniesiono. W niniejszym referacie przedstawiono wyniki badań równych połączeń drewnianych, tj. na czop, kołek i pierścień oraz dwóch komercyjnych klejów na bazie dyspersji polioctanowinylowej (PVAc). Drewniane ościeżnice zostały wykonane z drewna sosnowego w lokalnych zakładach. Ramiona próbek miały 450 mm długości i zostały sklejone razem pod kątem prostym. Wilgotność równowagowa próbek wynosiła 12%. Wytrzymałość graniczna belek kątowych różnie zastosowanych w profilach okiennych została przebadana na maszynie do testowania wytrzymałości na rozciąganie. Na końcach ramion próbek wywiercono otwory o średnicy 8.5 mm do zamocowania uchwytów maszyny do testowania wytrzymałości na rozciąganie. Następnie próbki zainstalowano w maszynie i poddano badaniu, zwiększając stopniowo siłę rozciągającą, aż do zniszczenia połączenia. Wartości wytrzymałości granicznej na rozciąganie zostały zmierzone w Newtonach (N) i jednocześnie zapisane. Wyniki badań pokazują, że średnia wytrzymałość graniczna połączenia z drewnianym pierścieniem jest większa niż wytrzymałość graniczna połączenia na czop, przy tym samym przekroju poprzecznym profilu i zastosowaniu tego samego kleju. Co więcej, zgodnie z oczekiwaniami wyniki jasno wskazują, że wytrzymałość połączeń na kołek była najmniejsza z trzech przebadanych profili okiennych. Ustalono, że połączenie z drewnianym pierścieniem jest odpowiednie do zastosowania w produkcji ościeżnic okiennych, ponieważ wytrzymałość tego połączenia okazała się większa niż wytrzymałość połączenia na czop, które jest obecnie przeważnie stosowane w produkcji okien, oraz znacznie większa niż wytrzymałość połączenia na kołek, które również jest stosowane w produkcji masowej. Przewagą połączenia z zastosowaniem drewnianego pierścienia jest jego uniwersalność, tj. niezależność od wymiarów czy przekroju poprzecznego profilu i jego struktury, co oznacza uproszczenie technologii, gdyż przekrój poprzeczny profilu lub jego strukturę można zmienić w każdym momencie, natomiast produkcja złącza kątowego powinna pozostać bez zmian. Okazuje się to szczególnie istotne wtedy, gdy producenci poszukują rozwiązań pozwalających zredukować ulatnianie się gazów cieplarnianych przez okna i w rezultacie stosują wielowarstwową konstrukcję ościeżnic okiennych lub elementy kompozytowe w produkcji ościeżnic okiennych i stojaków ościeżnicy

Greener adhesives based on UF/soy protein reinforced with montmorillonite clay for wood particleboard

There is a global concern about the types of adhesives used for the binding of wood particles, most of which include formaldehyde in their formulation. The aim of this work is to study the effect of raw montmorillonite (Mt) particles on blended urea formaldehyde (UF)/soy protein (SP) adhesives for the manufacture of wood particleboards to reduce the use of this carcinogenic component.Rheology showed that Mt does not alter the viscosity of adhesives at high shear rates, so they can be applied by spray. Thermogravimetric analysis/derivative thermogravimetry (TGA/DTG) analysis revealed an enhancement of their thermal stability due to the presence of clay particles. Polymer-Mt interaction was studied by small amplitude X-ray scattering and scanning electron microscopy. According to these results, the exfoliated structure of the clay particles was achieved. Wood particleboards were manufactured with UF/SP/Mt adhesives in order to study their mechanical properties. The three-point bending test showed that Mt particles improved the modulus of both rupture and elasticity. UF/SP/Mt resins proved to be a prominent product for the developmentof environmentally friendlier particleboards with desirable mechanical properties.Fil: Bacigalupe, Alejandro. Instituto Nacional de Tecnología Industrial; Argentina. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación e Ingeniería Ambiental; ArgentinaFil: Fernandez, Mariela Alejandra. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Tecnología de Recursos Minerales y Cerámica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Tecnología de Recursos Minerales y Cerámica; ArgentinaFil: Eisenberg, Patricia. Instituto Nacional de Tecnología Industrial; Argentina. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación e Ingeniería Ambiental; ArgentinaFil: Escobar, Mariano Martin. Instituto Nacional de Tecnología Industrial; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin