Temperature variation in distribution of relaxation times in aluminosilicate glasses

The distribution of relaxation times for the alkali peak in a Li₂ O·A1₂O₃ ·2.0SiO₂ glass and for the mixed alkali peak in a 0.5Li₂O·0.5Na₂O·A1₂O₃·2.OSiO₂ glass was studied using the internal friction technique. A lognormal distribution of relaxation times provided the best agreement with the experimental data. The ß parameter of the lognormal distribution function, which is related to the half-height peak width, varied with temperature, indicating that the distribution of relaxation times is dependent upon the activation energy and the activation entropy of the relaxation mechanism. The major contributor to the distribution of relaxation times is a wide distribution in the activation entropy, while the distribution in activation energy is relatively narrow. No noticeable change in internal friction was found when precautions were taken to eliminate any surface water on a specimen --Abstract, Page ii

A normative description of the role of the certified director of Christian education in the Methodist Church

Thesis (Ph.D.)--Boston University.(1) The library research traced the historical developments of the vocation of the employed local church director of Christian education in the Protestant churches and in The Methodist Church from its beginning in 1908, to the present time. This research supported the assumption that a description of the position of the director of Christian education is needed. 2) The questionnaire was sent to the pastor, the director, the chairman of the commission on education, and the church school superintendent in the 355 local churches where Methodist directors are employed. Fourteen hundred nine questionnaires were mailed. Seven hundred thirteen usable questionnaires were returned for a response of 50.6%. Seventy-five and seven-tenths per cent of the directors returned questionnaires. Significant areas of agreement and of disagreement were revealed among the four leaders concerning the work of the director. 3) Interviews were held with twelve individual respondents and with two groups with all four respondents, and one group in which three of the four respondents were included. Findings from the interviews were compared with those from the questionnaire and, although not an adequate sample, supported the findings from the questionnaires. 4) A normative description of the certified director of Christian education in The Methodist Church was formulated upon the basis of the research data. Normative description is used in this case to mean a statement of what ought to be the nature and work of the director. The following paragraphs are a summary of the normative description. A director in The Methodist Church is employed by the Quarterly Conference. The director is responsible to the pastor. He shares the ministerial function in a church large enough to need more than one minister on the employed staff. The specific assignment of the director is to guide the educational program of the church. He participates with other members of the employed staff in total church program development. The scope of the work of the director includes all that the church does that teaches. The director guides the commission on education, and works with teachers and officers of the educational program. He helps organize the work of Christian education. He helps persons know their jobs and helps them develop skills to do their work effectively. The director provides needed leadership functions in the educational program until indigenous leadership can be enlisted and trained. The director does not replace lay workers in responsibilities, but helps to see that persons are enlisted and trained for positions of service in the educational work of the church. The director works with teachers and officers as they need his guidance when they carry out their responsibilities. Educational projects of the district1 the annual conference, and the council of churches are an extension of the educational program of the local church, and as such should be a part of the director's responsibility. The work of the director should be defined in each church so he knows what to expect and so others in the church know what to expect of the director. The local church job analysis should be flexible so as to allow for the varied nature of the director's job. The specifics of the job of the director vary from church to church. It is important that each church where a director is employed create a specific job analysis for the work of the director in that church

Stresses in a thick spherical shell

This thesis reports a method to evaluate the stresses in a segment of a thick spherical shell. In the numerical examples loads due to thermal expansion as the shell is constrained at the free edge and a dead load acting vertically downward were considered for a shell assumed pinned but free to rotate and for a shell assumed completely fixed at the edge. A concrete shell was specifically studied but the method would also apply to a shell of any homogeneous, isotropic material --Abstract, page i

Development of a Task Analysis Tool to Estimate Shoulder Strain During a Lifting Task

Musculoskeletal disorders of the shoulder have a huge impact on the workplace and employees. Due to the complexity and high mobility of the shoulder, developing a task analysis tool with a focus on the shoulder is difficult, and while there are some ergonomic analysis tools that do consider the shoulder to varying degrees in the analysis, none focus purely on the shoulder. Therefore, this research was undertaken in an attempt to develop a shoulder-based task analysis tool for the shoulder. However, since the scope of work involving the shoulder is so vast, the tool in this research focuses on unobstructed, one-handed lifting tasks. An initial evaluation utilizing correlation and root mean square error analysis was performed using motion capture and electromyography data from participants performing a lifting task with dynamic and static portions using 3 different weights. Each task was modeled in AnyBody Modeling System with each available muscle recruitment algorithm. Based on correlation and root mean square error analysis between the muscle activations from the model and the collected electromyography data, the Min/Max strategy was most appropriate for static tasks and Poly4 strategy for static exertions. These selected muscle recruitment algorithms were used to model the tasks performed by the participants through the other sections of this research. Next, five participants performed static lifting tasks supporting a 15-pound weight throughout the reach zone of the right arm. These tasks were modeled in AnyBody using the Min/Max recruitment algorithm based on the results of the previous aim. Twelve potential composite index equations, designed to estimate shoulder strain based on AnyBody model outputs, were analyzed, three equations developed for this research and one previously-developed and validated equation. Correlation analysis between the results of each potential composite index and perceived exertions led toward the selection of one of the newly developed composite index equations, though the results were so close that the previously-developed equation was selected. Regression methods were used to develop a regression equation to predict the composite index values based on the distance to the load from the sternal notch. Finally, the hypothesis that the strain of an unobstructed lifting task would be highest at either the origin or the destination of the lift was tested to determine if the strain on the shoulder for a lifting task could be estimated based on the origin and destination of the load. Five participants were recruited to perform lifting tasks between low-, medium-, and high-risk load locations, and the peak predicted strain throughout the trial was compared to the strain at the origin and destination. It was determined that, due to an initial lift from the origin accompanied by an arced lifting trajectory, the peak strain was often slightly higher than at the higher of the origin or destination

The Case For the Educated Parent

Hogg Foundation for Mental Healt