In order to improve the flow state of a forebay, contraction diversion pier is discovered, geometric parameters which affect improvement state. this paper, standard k-? model in computational fluid dynamics (CFD) numerical simulation method used research forebay with pier. our research, single factor analyze influence different parameters. Then, optimal are given. Results show that can be conce...

Abstract Combining the characteristics of existing transfer slideway and double-point hanging type two retractable devices, this paper proposes a multiple-point hoisting, fast transfer, device. According to viscous flow theory, one-way fluid-structure interaction simulation is used for gondola structure unmanned boat Considering influencing factors width gondola, void ratio, shape distribution ...

The ignition, puffing and sooting characteristics of Chinese RP-3 kerosene droplet burning have been studied using high-speed, OH* chemiluminescence soot thermal radiation imaging. experiments were conducted in air at standard temperature sub-atmospheric pressures ranging from 0.2 bar to 1 bar. was supported by a thermocouple tip ignited retractable coiled heating wire. results showed that the ...

Hypersonic vehicles are an important development direction in aerospace, and their will have a significant impact on world security, the of cosmic space resources related disciplines. Along with rapid modern aircraft, landing gear is commonly used retractable technology, which brings series problems, such as design hatch retraction heat sealing mechanism evaluation air tightness. This paper tak...

Since the invention of the personal computer, digital media has remained separate from the physical world, blocked by a rigid screen. In this paper, we present Beyond, an interface for 3-D design where users can directly manipulate digital media with physically retractable tools and natural hand gestures. When pushed onto the screen, these tools physically collapse and project themselves onto t...

Recently, an increase in incidences of urinary tract infections in uncircumcised male infants has been reported. However, determining what is the best management for the prepuce of newborns and infants is still to be solved. I investigated prospectively how much foreskins are retracted with age and what correlations it has with urinary tract infection in 122 males children below 15 years of age...

According to the problem in communication protocol security assessments, a new protocol security comprehensive evaluation method based on the threedimensional sphere model is presented. In this method, a three-dimensional security evaluation index system was built through positions of index on the external of spherical shell. Evaluation index weights of the top two levels were obtained through ...

Recently a number of requirements engineer­ ing languages and methods have flourished that do not only address what questions but also why, who and when questions. The objective of this paper is twofold: (i) to assess the strengths and weaknesses of one of these meth­ odologies on a non-trivial benchmark, and (ii) to illustrate and discuss a number of challenging issues that need to be addresse...

Aspects of feeding, such as food capture and ingestion, as well as mobility of the polychaetes Eurythoe complanata, Marphysa formosa and Diopatra aciculata, from São Sebastião Channel (São Sebastião, state of São Paulo) were observed in laboratory conditions. Eurythoe complanata, a carnivorous species, fed exclusively on pieces of fish with the aid of strong muscular retractable lips, and detec...

The Lophotrochozoa includes disparate tentacle-bearing sessile protostome animals, which apparently appeared in the Cambrian explosion, but lack an uncontested fossil record. Here we describe abundant well preserved material of Cotyledion tylodes Luo et Hu, 1999, from the Cambrian (Series 2) Chengjiang deposits, reinterpreted here as a stem-group entoproct. The entoproct affinity is supported b...