Double curves

Woven fabrics are also available, however, with preforming powder (e.g., from Brochier SA). The formability of woven fabrics is limited and only moderately double-curved shapes have been formed commercially. Highly formable woven fabrics suited for thermoforming, however, have recently been introduced on the market (Brochier SA). This may increase the use of woven fabrics in industrial-scale preforming. 

How to Measure a Liquid. If you look through the side of a measuring glass filled with a liquid, you will see that the surface of the liquid has a double curve. This curve is called the meniscus. In measuring, be sure to use the lowest part of the lower.curve. Most liquids have a concave meniscus (one that curves downward) but very dense liquids like mercury have a convex meniscus (one that curves upward). In that case, use the uppermost part of the upper curve for measuring. 

Double curves (thermal pretreatment/atomization curves) are used to determine the limits for both thermal pretreatment and atomization temperatures for the elements and matrices involved. These curves can also be applied to drawing conclusions about the atomization mechanism. In the first curve the absorbance signal at the optimum atomization temperature is plotted versus the pretreatment temperature as the variable. In the second curve the absorbance at the optimum pretreatment temperature is plotted versus the atomization temperature as the variable (Figure 65). The pretreatment curve (ash curve) shows the temperature to which the sample can be heated without loss of the analyte. From this curve it is also possible to derive the lowest temperature at which the element is quantitatively volatilized. From the atomization curve can be derived the temperature at which the atomization is first evident, the appearance temperature, and the optimum atomization temperature at which the maximum atom cloud density is attained. 

The test tank, as shown in Fig. 2, is made of two flanged and dished 48 in. OD by l-in. wall, type-304 stainless steel ASME heads separated by a 7-in. long by -in. thick, type 304 stainless-steel cylindrical section. A 1 -in schedule-5S stainless steel neck tube was centered on one head for liquid fill, withdrawal, and instrumentation. This shape approximates that proposed for storage of fluids in space. Double curved surfaces provided an excellent test of the insulation-application technique. 

Wind tunnel is directly linked with the shaft together and tries to reduce the number of turning, which angle is less than sixty. All the connection comers should be smooth, especially the inside comer, which should be put into a double curves, we should use a sleek obtuse angle bend instead of an elbow bend. 

Double-curved shells can take the form of special domes, be saddle shaped, or use hyperbolic shapes, as featured in architectural design textbooks. These shapes can be made similar in modular forms molded with RP, thereby providing an efficient structural shape with a higher buckling resistance than special shapes of comparative curvature and thickness. Structural benefits are derived from using RP-faced sandwich designs in different shapes. 

With the three umbrellas in the courtyard of Industrie- und Handelskammer in Wurzburg, Germany, for the first time single-layer ETFE-foils in combination with a cable net (8 and 10 mm in diameter) were used for a double curved membrane with a low point. The edge lengths of the umbrellas, which are square in the layout, measure 6.5,11 and 14 m. The cable net is formed by meridian cables in ETFE-foil pockets and ring cables, which are positioned freely under the foil. 

Double-curved surfaces in pure tension may also be achieved by inflation e.g. soap bubbles, balloons and car tyres. However, these are synclastic forms where the curvatures in two perpendicular directions are the same (i.e. either both concave or both convex). 

The highly appealing lightweight and double-curved nature of textile surfaces lends itself to the development of exciting and sculptural as well as... 

Most studies have reported using a femoral vein approach. The left spermatic vein requires a double curve catheter to reach the ISV origin, and the right ISV is best entered with a sidewinder type catheter. Because of the double curve required to get into either spermatic vein, the femoral technique frequently requires coaxial catheters or a catheter exchange to reach an appropriate level in the ISV. 

Heat reformed JB 1 with extra sideholes Femoral approach, renal double curve guider left and Sidewinder 1 right... 

Several experimental devices have been set up to investigate the deformation modes and the possible occurrence of defects during forming of textile reinforcements. Hemispherical pxmch and die systems were particularly studied because the shape is rather simple, it is doubled curved, and because it leads to large shear angles between the tows [35-37]. In this paper, an experimental device is presented to form severe shapes. As an example, tetrahedron geometry is considered as it is much more difficult to form than hemispherical shapes, especially if the radiuses of curvature are small. 

Allaoui, S., et al., 2012. Experimental preforming of highly double curved shapes with a case comer using an interlock reinforcement. Int. J. Mater. Form. 7, 155-165. 

Figure 9. a) Vertical section of a double curved dam with symmetric TLCGD b) detailed schematic view of TLCGD smoothly integrated below the dam crest. Closedpressurizedpipe sections have equal volume. 

Diagnostic procedures are performed with 4 to 5 French diagnostic catheters single (Berenstein) or double curve (Sidewinder) depending on the tortuosity of the vessels. These catheters are used in combination with guidewires (0.035 ) (Fig. 18.6). 

Fig. 18.6. Diagnostic catheters with simple (Berenstein), double curve (Sidewinder) and guide wire with curved tip...

La Manantiales restaurant, Xochimilco, Mexico,1958 The almost hallucinogenic forms of Iberian baroque coincide with Felix Candela s investigation of double-curved surfaces. He made shapes definable by differential equations. Solved by consideration of the boundary conditions, these formulations produced elegant forms with light, feathered edges. 

The curve may be C-shaped or S-shaped. An S-shaped curve, a double curve with a convexity changing from one direction to another, is generally less deforming because the individual appears to be standing up straight. With the double curve, the lumbar spine is often involved as well. The C-shaped eurve ean cause a more misshapen appearance. In severe cases of thoracic scoliosis, the heart and lungs may become compromised. 

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