With the rapid increase in oil and gas consumption in the world’s energy consumption structure, the pace of global oil–gas pipeline construction has accelerated. Pipeline accidents that cause huge economic losses occur frequently, so inspection and maintenance of oil and gas pipelines have become critical issues. This paper presents a helical-contact deformation measuring method based on a mult...

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...

Pipe-in-pipe structure are widely used in offshore oil and gas transportation. The is subjected to various dynamic loads such as earthquakes vortex-induced vibrations during service, of which transverse impact the main cause damage. At present, whole process analysis parameter pipe-in-pipe under action not systematic complete. Based on explicit software LS-DYNA, finite element model was establi...

This paper proposes, for low buildings, an integrated wall structure of a brick-stem-insulating layer, which plays a major part in both heat preservation and force bearing. The research team has tested the thermal performance of the structure, the results of which are satisfying. To further study the force-bearing performance, the paper carries out compressive tests of specimens of different st...

This paper presents our efforts in the updating of the Storm Water (SW) Database using Global Positioning System (GPS), direct survey and measurements of the Storm Water structures (or called Manhole) in GIS database management. The main task assignments include (1) Designing a data structure, which becomes an effective geodatabase structure to represent the storm water structures and the corre...

Information personalization refers to the automatic adjustment of information content, structure, and presentation tailored to an individual user. By reducing information overload and customizing information access, personalization systems have emerged as an important segment of the Internet economy. This paper presents a systematic modeling methodology — PIPE (‘Personalization is Partial Evalu...

The structure of pipe networks minimizing the total energy dissipation rate is studied analytically. Among all the possible pipe networks that can be built with a given total pipe volume (or pipe lateral surface area), the network which minimizes the dissipation rate is shown to be loopless. Furthermore, such an optimal network is shown to contain at most N-2 nodes in addition to the N sources ...

The fluid-conveying pipe is a fundamental dynamical problem in the field of fluid– structure interactions. In recent years considerable attention has been given to the lateral vibrations of pipes containing by a moving fluid. In this paper, the vibration analysis of composite natural gas pipeline in the thermal and humidity environment is studied. The effect of the non-uniform magnetic field is...

When the velocity of fluid flow in a cantilevered pipe is successively increased, the system may become unstable and flutter instability would occur at a critical flow velocity. This paper is concerned with exploring the dynamical stability of a cantilevered fluid-conveying pipe with an additional linear dynamic vibration absorber (DVA) attachment. It is endeavoured to show that the stability o...