The present paper contains a detailed study of shock wave reflection from a wedge placed in various suspensions. In past works, the incident shock propagated initially in pure gas and the suspension started only at the leading edge of the deflecting wedge. However, in the present case the entire flow field is filled with a gas-dust suspension and the initial shock wave has steady-state structure relative to the shock front. In former studies the transmitted shock wave starts its propagation into the suspension and is reflected from the wedge at the same time. It is therefore obvious that the two unrelated processes of (2D) reflection and (1D) ''transitional'' relaxation occur simultaneously. In the present case the suspension behind the incident shock wave has reached steady state (i.e., it is a traveling wave) before the shock reaches the wedge leading edge.The reflection process from the deflecting wedge is studied for different dust mass loadings and different dust-particle diameter. It is shown that when the dust loading is low and the dust particle diameter is small the wave reflection pattern is similar to that observed in a similar pure gas case. In addition, an equilibrium state is reached, behind the evolved waves, very quickly. On the other hand, when the dust loading is relatively high and/or the dust particle diameter is relatively large, the observed reflection wave pattern is very different from that seen in a similar pure gas case. In such cases it takes much longer time to reach an equilibrium state behind the reflecting waves. It is also shown that the dust presence significantly affects the (gas) pressure on the wedge surface. The higher the dust loading is, the higher the pressure on the wedge surface. Suspensions composed of solid particle of different size, but having the same dust mass loading, will approach the same equilibrium pressure. However, it will take longer time to reach an equilibrium state for suspensions having large diameter particles.

The auricular conchae of 310 young Chinese people (169 men and 141 women) aged 18–28 years were classified into different groups and differentiated in terms of shape as a basis to designing wearable and non‐slip earphones. Seven characteristic distances could be obtained accurately by defining 5 characteristic points and extracting their 3‐dimensional (3D) coordinates from 3D digital models (obtained by scanning 310 ear impressions) automatically. The shape differences of auricular conchae were statistically analyzed. Results show that the average dimensions of auricular conchae for men are generally larger than those for women, and the shapes of auricular conchae significantly differ among the participants. The shapes of auricular concha were classified into 24 groups, depending on the characteristic distances. For each group, the coordinates of 5 common‐characteristic points were determined and the basic shape was summarized. The percentage of the samples in each group was statistically given, and 8 prioritized groups of samples more than 5% were suggested. Finally, the feasibility of the classification method was demonstrated by designing earphone, 3D printing, and wearing verification.

We report on the use of x-ray diffraction as a means of extracting velocity profiles from a non-Newtonian complex fluid under laminar flow. In particular, we applied this technique to a concentrated undulating membrane system flowing through a cylindrical capillary tube. The intermembrane separation d was measured as a function of simple shear using a Couette flow cell. A logarithmic dependence of d as a function of the shear rate was observed, while there was a linear relationship between the fractional intermembrane spacing and the shear stress. Subsequent measurement of the system's intermembrane spacing as a function of position within the cylindrical flow pipe allowed for the calculation of a shear-rate profile within the capillary. Simple numerical integration then yielded an accurate velocity profile of the fluid flowing through the pipe. Both shear thickening and plug flow shear thinning profiles were observed.

SUMMARY:A detailed data of concha is currently not available. Therefore, the present study aimed to determine twelve morphometric measurements of concha, to investigate its sexual dimorphism and bilateral asymmetry, and to establish basic shapes of concha for both sexes and sides. The study sample comprised of 310 young Chinese aged 18-28 years. 141 left and 141 right ear impressions for females, 169 left and 169 right ear impressions for males were collected and scanned. The 3D coordinates of seven landmarks on each auricular concha were obtained using 3D scanning technology and curvature theory. From the landmarks, twelve morphometric measurements of concha were calculated and analyzed. The conchal morphometry exist significantly sexual dimorphism in this study sample. On average, all measurements were larger in males than in females regardless of the sides. There was significantly bilateral asymmetry among left and right conchae in both sexes. Some measurements were larger in the right sides and some measurements were larger in the left sides, but the bilateral difference in both measurements found to be less than 1mm. Additionally, the basic shapes of concha for both sexes and sides were established on the basis of the mean 3D coordinates of each landmark and the mean value of each measurement. The anthropometric method of this study could overcome the difficulty in locating landmarks of auricle complex structures, and attain a higher level of accuracy in the procedure of measurement. The quantitative description of conchal morphometry will be beneficial for plastic surgeons, and for the ergonomic design of hearing aids.

While a lot of attention was given to shock wave reflections from wedges during the past four decades, only little work was published regarding the similar case of blast wave reflection from wedges. In the present paper this subject is studied experimentally and theoretically/numerically. The obtained results show that the geometry of the reflected wave pattern is similar in the two cases when both incident waves have the same initial pressure jump across their fronts. However, different reflected pressure signatures (history) are observed in these two cases. The pressures obtained behind a reflected shock wave are always higher than those obtained behind the corresponding similar blast wave. In the present case differences as high as 17% were observed.