Time filter

Source Type

Zeng F.,Hunan University | Tang Y.,Hunan University | Pu J.,Yunnan Electrical Power Design Institute
The Scientific World Journal | Year: 2014

Considering the limited resources and the dynamic spectrum distribution in the cognitive radio sensor networks (CRSN), a half-duplex Multichannel broadcast protocol for CRSN is presented based on the home channel. This protocol maintains the networks topology only through the home channel, so there is no need for the public channel to transmit the control information and no need for the synchronization. After network initialization, node broadcasts data via home channel in half-duplex transmission way. The simulation results show that, compared with complete broadcast, the proposed protocol effectively reduces broadcast delay and overhead. © 2014 Fanzi Zeng et al. Source

Huang J.-H.,Chongqing University | Chen Z.-H.,Chongqing University | Ma D.-S.,North China Power Engineering Company | Li G.-Y.,Yunnan Electrical Power Design Institute
Gongcheng Lixue/Engineering Mechanics | Year: 2012

The elevated box girders would bear an additional large soil pressure and a vehicle load because of the backfilling of gulch and road construction caused by the function changes of urban lands. The change of a load case would result in the failure risk of a pipeline structure. The static properties of the reinforced concrete deep elevated box girders commonly used in the urban sewage pipeline system are experimentally analyzed. The failure pattern, shear lag effect and shear behavior of such deep box girders are studied. The shortages in the present design codes for the calculation of bending capacities of the box girders are also discussed. The box girder is simulated by using the non-linear finite element method. It is shown that under the vertical uniformly distributed load, the failure pattern of the simple-supported rectangular deep box girder with a depth-to-span ratio of nearly five is bending failure. The shear lag effect in the mid-span section is non-obvious, while it is more obvious before cracking in a quarter-span section. However, the lag effect is weakened gradually after cracking. The results simulated by the non-linear finite element method show an agreement with the experimental results. In order to avoid the premature cracking which affects the serviceability of a sewage pipeline, reinforcing measures should be carried out before the backfilling to the designed simple-supported sewage pipeline. Source

Gao M.,Yunnan Electrical Power Dispatching Center | Yuan L.,Yunnan Electrical Power Design Institute | Li W.-Y.,Yunnan Electrical Power Dispatching Center | Luo X.-L.,Yunnan Electrical Power Institute
Dianli Xitong Baohu yu Kongzhi/Power System Protection and Control | Year: 2011

Some key problems of power dispatching system information construction are discussed. The related research and application of the power dispatching comprehensive data platform is proposed to be promoted to the power dispatching system information. The relationship between the dispatching information and the intelligent dispatching is discussed, the construction mode of the dispatching information is discussed and advised, and the relationship between the dispatching information and the dispatching automation is determined. The dispatching business is summarized and divided, the application functions are mapped from them, the application systems framework is obtained according to the application functions, and some examples are given. The data structure of the dispatching system information is deduced, and an example of the transverse data stream analysis is given. Source

Wang Z.,University of Sichuan | Tan L.,University of Sichuan | Tan L.,Yunnan Electrical Power Design Institute | Wang Q.,University of Sichuan
International Journal of Steel Structures | Year: 2013

Fatigue strength evaluation of welded structural details is of practical significance in the design of corrugated steel web girders in highway bridges and industrial structures. In this paper, the fatigue strengths of corrugated steel web girders with several welded structural details and welding methods are analytically examined by fatigue tests of corrugated web beams and small-size welded joints. The stress concentration & distribution characteristics of corrugated web beams were analysed using finite element analysis. The beam test results showed that the structure with scallops or notches in the flange has lower fatigue strength and that with butt joints is prone to suffer from shear crack on the corrugated web. Within the inside range of the scallop, the stress concentration becomes greater with the increase of scallop radius and the tension flange contributes significantly to the bending capacity of corrugated steel web beams. The tests for small-size welded joints indicated their applicability in the analysis and prediction of S-N relationship of the test corrugated steel web beams. Finally, the fatigue crack propagation lives of weld joints were compared with those of test corrugated steel web beams with respect to related design Categories of the AASHTO LRFD Bridge Design Specifications. © 2013 Korean Society of Steel Construction and Springer-Verlag Berlin Heidelberg. Source

Cao P.Z.,Hohai University | Li D.,Hohai University | Lin R.Z.,Yunnan Electrical Power Design Institute
Applied Mechanics and Materials | Year: 2014

A new Steel deck-concrete composite floor slabs was proposed that with the effect of het preservation and insulation, and the flexure performance of the slabs has been studied. Calculation method of flexural bearing capacity was put forward. Based on comparative and analysis experimental results, it has been verified that the applicability of new formula of flexural bearing capacity of the new slabs. © (2014) Trans Tech Publications, Switzerland. Source

Discover hidden collaborations