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The generalizability theory, an expansion of classic true-score reliability theory, was used to investigate the generalizability of observed segmental extracellular fluid (ECF) and intracellular fluid (ICF) distribution measurements. The test instrument was a Xitron Hydra ECF/ICF bioimpedance analysis system model 4200, Xitron Technologies, San Diego, CA. Fifty American healthy men (17-72 years) and 50 American healthy women (17-76 years) volunteered as participants. Xitron continuous segmental ECF-ICF procedures for testing leg segmental data were followed for testing participants in both the standing erect and lying supine postures. A two-facet, person-by-trial, completely crossed design was used. All facets were treated as random. During a one-day session each subject was tested involving 20 trials for the standing erect posture and 20 trials for the lying supine posture. Data on each fluid measurement, each body posture and each sex group were independently analysed. The analyses revealed that the trial factor accounted for less than 0.2% of the total variance for ECF and ICF scores. ECF and ICF generalizability coefficients for the segmental method were 0.99 or greater. In comparing ECF segmental to ECF global, results showed generalizability coefficients were similar. However, ICF segmental coefficients were larger than the coefficients produced by the global method. In conclusion, the segmental method appeared more reliable than the global method, under the conditions of this study.

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Generalizability theory was used to investigate the score consistency of observed extracellular fluid/intracellular fluid (ECF/ICF) ratio measurements for both the global and leg-segmental bio-impedance spectroscopy methods. The test instrument used was a Xitron Hydra ECF/ICF Bio-Impedance Analyzer System, model 4200 (Xitron Technologies, San Diego, CA). Fifty able-bodied American men (17 to 72 years) and 50 able-bodied American women (17 to 76 years) volunteered as experimental subjects. Xitron continuous global and leg-segmental ECF/ICF procedures for testing were followed for assessing subjects in both the standing erect and lying supine postures. A two-facet, person-by-trial, completely crossed design was used, and all facets were treated as random. Data were independently analyzed for each method, each body posture and each sex group. The major findings of this study were: (1) the leg-segmental method was superior in producing the higher G-coefficients when compared to the global method regardless of gender or posture; (2) the global method resulted in higher G-coefficients in males compared to females regardless of posture; (3) when the global method was used, the relative and absolute error variances were higher for females while the opposite trend was observed when the segmental method was used and (4) when using the global method, the precision of the ECF/ICF ratio scores in females could be increased by simply using the mean of several trials (e.g., by using the mean of 5, 10 or more test trials).

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Students pursuing an Associates Degree in Biomedical Engineering Technology at Penn State University are required to complete a 400-hour internship in an approved health care facility before graduation. This paper analyzes how the students perceive the need to be involved in the internship, including its effect on their professional development as well as on their ability to perform the tasks associated with their responsibilities. The students were asked to describe and summarize their experiences in the workplace in a daily log, to write a formal report describing in detail a project that they undertook and provide a comprehensive description of their experience. The effect of working in a Clinical Engineering department before graduation strongly increased the students' confidence in their strengths and made them aware of those items that required further attention and development. A very positive outcome from the cooperative experience was the full employment of all the students involved in the program, in the places where they carried out their internships or through contacts developed at that time. The paper also analyzes the results of a survey given to the students' supervisors. They were asked to describe and evaluate the qualities most needed in entry level biomedical engineering technicians, and how these qualities changed during the internship period for the students that they supervised. All the clinical engineering supervisors stressed the positive effects of the internship experience in creating qualified professionals in the field at the service of the society.

A microcontroller-based system is used to illustrate experimental concepts in a Control Systems course in an Electrical Engineering Technology program. Students are able to experiment with different control strategies ranging from an open-loop to PID control. Students are asked to reason and discuss the benefits and drawbacks associated with each strategy. The microcontroller system has been chosen to minimize the learning curve for the students in such a way that they are mostly concerned with acquiring and representing the appropriate signals from the system as well as experimenting with changing the parameters of the system in each case.