Thermal-Feature System Identification for a Machine Tool Spindle

The internal temperature is an important index for the prevention and maintenance of a spindle. However, the temperature inside the spindle is undetectable directly because there is no space to embed a temperature sensor, and drilling holes will reduce its mechanical stiffness. Therefore, it is worthwhile understanding the thermal-feature of a spindle. This article presents a methodology to identify the thermal-feature model of an externally driven spindle. The methodology contains self-made hardware of the temperature sensing and wireless transmission module (TSWTM) and software for the system identification (SID); the TSWTM acquires the temperature training data, while the SID identifies the parameters of the thermal-feature model of the spindle. Then the resulting thermal-feature model is written into the firmware of the TSWTM to give it the capability of accurately calculating the internal temperature of the spindle from its surface temperature during the operation, or predicting its temperature at various speeds. The thermal-feature of the externally driven spindle is modeled by a linearly time-invariant state-space model whose parameters are identified by the SID, which integrates the command “n4sid” provided by the System ID Toolbox of MATLAB and the k-fold cross-validation that is common in machine learning. The present SID can effectively strike a balance between the bias and variance of the model, such that both under-fitting and over-fitting can be avoided. The resulting thermal-feature model can not only predict the temperature of the spindle rotating at various speeds but can also calculate the internal temperature of the spindle from its surface temperature. Its validation accuracy is higher than 98.5%. This article illustrates the feasibility of accurately calculating the internal temperature (undetectable directly) of the spindle from its surface temperature (detectable directly).

Investigation of alpha-wave frequency characteristics in the patients with chronic tension headache and its modification during electromyographic-temperature training

Chronic tension headache is the most commonly experienced headache. Low effectiveness of its treatment is connected with lack of understanding of this disorder pathogenensis. It was shown that electromyographic-temperature training provoked modification of alpha-wave power and frequency: power of alpha increased, frequency of maximal increased as well.

Comparison of Feedback Modalities in Biofeedback Temperature Training

Much of what is presented to clients in a biofeedback session is integrated only if learning occurs. Biofeedback is not effective if the learner does not understand the signals. Neurolinguistic programming suggests that individuals utilize primary representational systems, including vision and audition, to incorporate environmental stimuli into their own preestablished notions of the world. To test this, individuals were included in one of four treatment modalities: control group, visual feedback only group, auditory feedback only group, or visual/auditory feedback group. Groups were significantly different only in decay rate from peak temperatures. Sex differences indicated women consistently produced cooler hand temperatures than men. Visual feedback seemed to be the most effective type of feedback for persons in this experiment.

Biofeedback and Control of Skin Cell Proliferation in Psoriasis

The present study was designed to determine the effect of skin-temperature-biofeedback training on cellular proliferation in three psoriasis patients. It was hypothesized that (a) psoriasis patients would be able consciously to decrease skin temperature of psoriatic tissue and (b) there would be a positive correlation between rate of cellular proliferation and temperature change. Results obtained indicated biofeedback training to be effective in decreasing the surface temperature of psoriatic tissue. Temperature-training effects generalized from the location of the thermistor to the contralateral limb. Rate of cellular proliferation decreased from pretraining to post-training biopsies. Dramatic improvement in psoriatic plaques was usually observed up to 4 mo. posttraining.