Noise of small-scale contra rotating rotors

This article presents the results of an experimental study of the noise characteristics of small-scale coaxial counter-rotating rotors. The tests were carried out in an anechoic soundproof chamber for F7/A7 counter-rotating rotors with 11 and 9 blades on the front and rear rotors, respectively. The intensity of noise emission by rotors was compared with the constancy of the thrust of the power units. Acoustic studies have shown the presence of tonal and broadband noise components at low rotation speeds. In addition to the usual noise components, tonal components were also observed for the rotor blade running combinations. The observed noise levels at these frequencies are equal, and in some directions are significantly higher than the noise levels at the frequencies of the blades of the first and second rows. In experiments, it was found that, while maintaining the equality of the rods, with an increase in the diameter, the noise levels at the rotors decrease due to a decrease in peripheral speeds. A decrease in the noise levels of rotors with an increase in the number of blades was established due to a decrease in aerodynamic loads on the blades and peripheral speeds. An important parameter here is the filling factor of the space swept by the blades. With an increase in this coefficient, the rotation noise decreases, but the vortex noise increases significantly.

Facial expressions alter the fundamental sound properties of speech

Literature from across academic disciplines has demonstrated significant links between emotional valence and language. For example, Whissell’s Dictionary of Affect in Language defines three dimensions upon which the emotionality of words is describable, and Ekman’s Theories of Emotion include the perception and internalization of facial expressions. The present study seeks to expand upon these works by exploring whether holding facial expressions alters the fundamental speech properties of spoken language. Nineteen (19) participants were seated in a soundproof chamber and were asked to speak a series of pseudowords containing target phonemes. The participants spoke the pseudowords either holding no facial expression, smiling, or frowning, and the utterances recorded using a high-definition microphone and phonologically analysed using PRAAT analysis software. Analyses revealed a pervasive gender differences in frequency variables, where males showed lower fundamental but higher formant frequencies compared to females. Significant main effects were found within the fundamental and formant frequencies, but no effects were discerned for the intensity variable. While intricate, these results are indicative of an interaction between the activity of facial musculature when reflecting emotional valence and the sound properties of speech uttered simultaneously.

Synapsis Expression Increased By Mozart’s Music Stimulation Compared With Indonesian Pop And Religious Music

Classical music stimulation is a proven method that affect intelligence as well as brain function. Mozart’s classical music is classical music that could stimulate the growth of synaptic networks. To analyze the difference of synapsin expression of the brain of Rattus norvegicus offspring on Mozart’s, pop, religious and without music stimulation during pregnancy. Experimental. Treatments were subjected to Rattus norvegicusas a subject organism, initiated on the 10th day of pregnancy, in 1 hour duration in a soundproof chamber, intensity of 65 dB. On the 19th day of pregnancy the subjects were sacrificed and three offsprings were chosen. The head of the chosen Rattus norvegicusoffsprings were decapitated and the brain subsequently sectioned to calculate synapsin expression by immunohistochemistry method with 400 magnification strength microscope on the 5 field of view. Significant difference of synapsin expression of the brain of Rattus norvegicus offspring was observed between Mozart’s and control group. Significant differences of synapsin expressions were observed in the cerebellum of the newly born Rattus novergicus between Mozart and pop music groups (p = 0,007), Mozart and religious music groups (p = 0,008), Mozart and without music groups (p = 0,004).Synapsin expression of Rattus norvegicus brain offsprings were higher in Mozart music stimulation compared with pop and religious music stimulation

Mozart Music Increases The Number Of Glial Cells Compared To Indonesia Pop And Religious Music

Music stimulation is an important component for prenatal fetal development. Both pop and religious music are easy to listen and widely accepted in Indonesia. This study was to analyze the effect of Mozart, pop, and religious music exposure during pregnancy to the number of glial cells in the brain of Rattus norvegicus offspring. The samples were divided into three groups based on the exposure for each group, namely Mozart, pop, and religious music, duration of 60 minutes with 65dB intensity, initiated on the 10th day of pregnancy for 9 days in the soundproof chamber. Three brains of the offsprings were dissected and prepared for Hematoxylin-Eosin staining counted on 5 fields of view and 400 magnification strength.Different glial cells number of Rattus norvegicus brain between groups were observed. Mozart music (28,29) showed a highest mean and pop music (18,67) showed the lowest mean. Significant difference of the number of brain glial cells between Mozart music compared to pop and religious music groups were observed, with p value <0,005.The number of brain glial cells of Rattus norvegicus offsprings in the Mozart group were significantly higher than those in pop and religious groups.

Information-Deprivation and Creativity

An experiment tested the hypothesis that highly creative Ss have more need for information than Ss low in measured creativity. 36 Ss were selected from the extremes of a larger group who had taken the Remote Associates Test (RAT). 22 Ss scored high (highly creative) and 14 Ss scored low (low-creatives) on the RAT. All Ss were deprived of information, i.e., placed in a lightproof and relatively soundproof chamber, for 8 hr. After 1 to 5 hr. one-half the Ss at each level of creativity were given access to information (a choice between two sequences of photic stimulation differing as to their informational content). An instrumental response activated the apparatus and caused brief flashes of light to appear in the ceiling of the experimental chamber. Results support the hypothesized motivational effect.

Effects of external elastic and threshold loading on breathing in man

Conscious human subjects, seated in a soundproof chamber, were made at intervals to inspire through external elastic or threshold loads for from 4 to 15 breaths With threshold loading of -5 to -15 cm H2O (13 subjects) initially, the first loaded breath was smaller than preceding breaths with tidal volume returning to normal within 6 breaths. With further presentations, tidal volume returned to control values sooner. After six presentations, 10 subjects had no diminution in tidal volume on the first loaded breath. With elastic loading, of 10 cm H2O/liter (five subjects) and 19.5 cm H2O/liter (four subjects) a different type of adaptation occurred. This was characterized by decreased tidal volume and increased frequency. With the larger load, after three presentations frequency was increased during loaded breathing, due to a conscious effort by the subjects. The results show that repeated presentation of an elastic or threshold load leads to a change in the response to the load in a manner analogous to the learning of voluntary motor acts. respiration; learning; tidal volume; respiratory frequency; regulation of respiration Submitted on July 9, 1964