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The present paper aims at optimization of multiple quality characteristics (dimensional accuracy and surface roughness) in dry drilling Ti-6Al-4V using TiAlN-coated carbide tool while the controllable factors are spindle speed and feed rate. To do so, desirability methodology is used to explore optimum conditions for concurrent optimization of the addressed quality characteristics. Central composite design (CCD) is used for experimentation. In order to create reliable models describing the process behavior, response surface methodology (RSM) is used.

In this review study, information on efficiencies and characteristics of different exercises is presented with the goal of using the information for modeling extra-vehicular activity (EVA). Muscle activation is reported for running, walking, and cycling. The deviation and uncertainties in efficiency will be assessed along with effects of workload, rate of exercise, training, and various physiological parameters. The uncertainty involved in using VO2 consumption as a measure of metabolic rate is discussed. The information reported will be related to efforts to analyze exercises to simulate EVA on Earth.

This paper gives an overview for a new human thermal model. A compromise between simplicity and accuracy when developing the new thermal model is determined. The human thermal model incorporates 2-dimensional (radial and angular) heat transfer along with arterial and venous countercurrent blood flow. In addition, this thermal model attempts to model the human digits in order to predict toe and fingertip temperatures that are of special interest in regards to possibility of controlling the thermal comfort of a subject.

This paper discusses several issues related to the PLSS thermal model requirements for a planned generalized EVA Simulation Test Bed. The existing models of the extravehicular mobility unit (EMU) are briefly discussed and then the paper focuses specifically on the NASA JSC Shuttle EMU model (referred to as SINDA EMU). After the SINDA EMU model review, the PLSS thermal model requirements for the EVA Simulation Test Bed are discussed in detail.