An investigation on enhancement of heat transfer is carried out for a double pipe exchanger in which the outer wall inner provided with circumferential labyrinth passages. Rectangular and triangular cavities fixed tooth thickness, height, pitch are considered effect added structures characteristics discussed. A two-dimensional steady numerical simulation using ANSYS-FLUENT software. The flow Re...

We introduce the Peripipe, a tangible remote control for a music player in the shape of a wooden tobacco pipe. The interaction is based on breath control, using sips and pu↵s as control commands. An atmospheric pressure sensor in the Peripipe senses changes in the air pressure. Based on these changes, the pipe determines when the user performs a pu↵, double-pu↵, sip, double-sip or a long pu↵ or...

This paper reconsiders the established Merkle-Damg̊ard design principle for iterated hash functions. The internal state size w of an iterated n-bit hash function is treated as a security parameter of its own right. In a formal model, we show that increasing w quantifiably improves security against certain attacks, even if the compression function fails to be collision resistant. We propose the w...

A secure hash structure in Random Oracle Model may not be a secure model in true design. In this paper, we give an integrated proof method on security proof of iterated hash structure. Based on the proof method, we can distinguish the security of Merkel-Damag̊ard structure, wide-pipe hash, double-pipe hash and 3c hash and know the requirement of true design on compression function, and give a ne...

A high-temperature steam generation system to supply a water electrolysis was designed and tested using solid-recovered fuel (SRF). The energy loss must be reduced hydrogen production stably, which are conducted by three strategies: (a) double pipe, (b) installing baffle inside the pipe obstruct flow, (c) bypassing overflowing steam. Double 25% compared single pipe. Consequently, heat source wi...

In this research, heat transfer enhancement and simultaneous effect of that on pressure drop inside condensers with twisted tape inserts are investigated. A refrigeration system is designed for attaining to maximum level of heat transfer with minimum pressure drop. The test condenser is a double pipe heat transformer with inner and outer diameter of 10.7mm and 12.7mm for internal pipe, respecti...