Direct Slicing Based on Material Performance and Process Parameters for Selective Laser Sintering

Direct slicing from GAD models to generate sectional contours of the part to be sintered for Selective Laser Sintering （SLS） may overcome inherent disadvantages of using a Stereo Lithography （STL） format. In this paper, a direct slicing procedure is proposed for Selective Laser Sintering based on material performance and process parameters. Slicing thickness depends on the 3 D geometric model, material performance and process parameters. The relationship among material performance, process parameters and the largest slicing thickness is established using analysis of a sintering temperature field. A dynamic linked library is developed to realize direct slicing from a CAD model.

Effects of Cultivar, Frying Temperature and Slice Thickness on Oil Uptake and Sensory Quality of Potato Crisps Processed from Four Kenyan Potato Cultivars

The effects of potato cultivar, frying temperature and slice thickness on oil uptake and sensory quality of potato crisps were investigated in four Kenyan cultivars. Potato tubers were peeled, washed and cut into slices of thickness 1.0 mm, 1.5 mm and 2.0 mm. Each size was fried at a constant temperature of 170 ℃ for 3-5 minutes. For frying temperature evaluation, the potatoes for all cultivars were cut into a uniform thickness of 1.5 mm and fried at temperatures of 160, 170 and 180 ℃ for 2-5 minutes. Crisps made from the four cultivars differed significantly （P 〈 0.05） in oil absorbed which ranged from 35.12% in Dutch Robyjn to 36.52% in clone 391,691.96. Tuber dry matter differed significantly （P 〈 0.05） among the cultivars ranging from 20.99% in clone 391691.96 to 25.29% in variety Dutch Robyjn. Tuber dry matter content was found to be negatively correlated to oil content of crisps; oil content increased with decrease in dry matter content. For each cultivar, the oil content of crisps differed significantly （P 〈 0.05） with temperatures and was higher at frying temperatures of 160 ℃ and lowest at 180 ℃, respectively. The oil content was significantly （P 〈 0.05） higher in slices of 1.0 mm thick than in slices of 1.5 mm and 2.0 mm; the amount ofoil absorbed decreased with increase in slice thickness. There was significant correlation （P 〈 0.05, r = -0.834） between oil content as determined in the laboratory and sensory scores. Results showed that high dry matter, slice thickness and temperature of frying resulted in reduced oil absorption by crisps during processing.

Effect of Some Processing Variables on the Quality Attributes of Yam Flour

The effect of varied processing variables （yam slice thickness, drying temperatures and type of drying） were investigated to determine their effects on the proximate and some functional properties of yam flour. The yam flour was produced with different slice thickness of 1, 1.5, 2.0, 2.5 and 5 cm using both conventional sun drying method and oven drying at temperatures; 40 ~C, 50 ~C, 60 ~C and 70 ~C. The moisture content of all the yam flour samples increased with increasing yam slice thickness, with the samples sun dried having the lowest values （6.20%-6.87%） followed by those dried at 70 ~C and then 60 ~C. The protein content of the yam flour samples increased with increase in slice thickness and decreased with increase in drying temperatures while the fat and the crude fibre of all the yam flour samples decreased with increase in slice thickness. The water absorption capacity of the sun dried yam flour samples decreased with increase in slice thickness while the syneresis value, bulk density and the gel strength increased with increase in slice thickness for all drying temperatures and for sun dried yam flour samples but smaller slice thickness had higher swelling capacity.

The accuracy and optimal slice thickness of multislice helical computed tomography for right and left ventricular volume measurement

Background Multislice helical computed tomography (MSCT) has been used to depict coronary anatomy noninvasively, and proved useful for evaluating ventricular function. The aim of our study was to assess the accuracy of ventricular volume as measured by MSCT.Methods Fourteen human left ventricular (LV) and 15 right ventricular (RV) casts were scanned by MSCT. A series of LV and RV short-axis images were reconstructed later with slice thickness of 2.0 mm, 3.5 mm, 5.0 mm, 7.0 mm, and 10.0 mm. Ventricular volume was calculated by the multislice tomographic Simpson’s method. True LV and RV cast volumes were determined by water displacement. Results Both calculated LV and RV volumes correlated highly with the corresponding true volumes (all r>0.95, P<0.01). But with slice thickness from 2.0 mm to 10.0 mm, MSCT scanning overestimated the corresponding true volume by (3.21±5.95) ml to (12.58±8.56) ml for LV and (10.22±8.45) ml to (23.91±12.24) ml for RV (all P<0.01). There was a very high correlation between the overestimation and the selected slice thickness for both LV and RV volume measurements (r=0.998 and 0.996, P<0.01, respectively). However, when slice thickness was reduced to 5.0 mm, the overestimation for both LV and RV volume measurements became nonsignificant for slice thickness from 2.0 mm to 5.0 mm. Conclusions Both LV and RV volumes can be accurately estimated by MSCT. Thinner slice has more accurate calculated volume. However, 5.0 mm slice thickness is thin enough for an accurate measurement of LV or RV volume.