Fault Analysis and Innovation in Slag Discharge System of 440-t/h CFB Boiler

CFB boilers have been widely used in China in recent years with their perfect performances in coal adaptability, load variation capability and lower pollutant emission. The No.3 135-MW CFB unit in Lianzhou Power Plant is the f irst 440-t/h series CFB unit in Guangdong Province. It f inished 72-hour trial operation in Feb. 2004 and was transferred to trial operation. During the trial operation and the next commercial operation, there were some problems happened in the boiler slag discharging system, seriously affecting the safe and reliable operation and the loading capability. After innovation, these problems have been completely solved. Hopefully the solutions may be used for reference to the units with similar problems.

Analysis on Technological Innovation of Civil Engineering Construction

As an important means of human to change their living environment, building creates important wellbeing for people’s production and life, while as an important means of building construction, civil engineering plays an absolutely important role in the architectural construction. The fruitful innovation in the construction of civil engineering undoubtedly has a very important meaning and value for the development of civil engineering discipline and for the realization of human wellbeing. This paper makes analysis on several means of technological innovation of civil engineering construction, purposed to promote the practical development of civil engineering through helpful discussion and exploration.

Assessment of recharge capacity potential of groundwater using comparative multi-criteria decision analysis approaches

Groundwater resources have always been some of the most valuable resources of human settlements.Climate changes and ever-increasing water demands registered in the last century have led to diminishing levels of groundwater reserves,as well as reduced recharging potential.Therefore,in order to use groundwater aquifers in a sustainable manner,it is required to identify areas with higher replenishing potential.The current study addresses the issue of generating a map for identifying differently ranked groundwater recharging potential values,in the aquifers of the Moldavian Plain region,Romania.For the purpose of conducting the analysis,maps were created through GIS based multi-criteria Analytic Hierarchy Process(AHP)and Catastrophe Theory(CT),with seven relevant,thematic,spatial layers:precipitation distribution,lithological strata,soil texture,declivity,drainage density,land use and the distribution of groundwater level tendencies.The results of the two methods of analysis are similar.Prediction differences are of maximum 3%,in the case of extreme classes(very bad and very good)and in the case of middle classes the deviation is not greater than 0.4%.Following the validation of the results generated by the two methods that were applied,it was observed that the predictions offered by CT are more accurate.This aspect can be based on the fact that the main factors that contribute to the prediction are different.This type of workflow emphasizes the necessity of implementing appropriate groundwater management plans for mitigating reservoir scarcity/depletion,and recommending sustainable solutions for future groundwater exploitation practices.

Optimal linear estimators for systems with random measurement delays

This paper is concerned with the optimal linear estimation problem for linear discrete-time stochastic systems with random measurement delays. A new model that describes the random delays is constructed where possible the largest delay is bounded. Based on this new model, the optimal linear estimators including filter, predictor and smoother are developed via an innovation analysis approach. The estimators are recursively computed in terms of the solutions of a Riccati difference equation and a Lyapunov difference equation. The steady-state estimators are also investigated. A sufficient condition for the convergence of the optimal linear estimators is given. A simulation example shows the effectiveness of the proposed algorithms.

H_∞ FILTERING FOR CONTINUOUS-TIME SYSTEMS WITH POINTWISE TIME-VARYING DELAY

The problem of H∞ filtering for continuous-time systems with pointwise time-varying delay is investigated in this paper. By applying an innovation analysis in Krein space, a necessary and sufficient condition for the existence of an H∞ filter is derived in two methods： One is the partial differential equation approach, the other is the reorganized innovation analysis approach. The former gives a solution to the proposed H∞ filtering problem in terms of the solution of a partial differential equation with boundary conditions. The later gives an analytical solution to the proposed H∞ filtering problem in terms of the solutions of Riccati and matrix differential equations.

Design of fixed-point smoother algorithm for linear discrete time-delay systems

This paper investigates the fixed-point smoothing problems for linear discrete-time systems with multiple time-delays in the observations. The linear discrete-time systems considered have 1 ＋ 1 output channels. One is instanta- neous observation and the others are delayed. The fixed-point smoothers involving recursive algorithm and non-recursive algorithm are designed by using innovation analysis theory without relying on the system augmentation approach. Also, it is further shown that the design of fixed-point smoother comes down to solving 1 ＋ 1 Riccati equations with the same dimensions as the original systems.

Kalman filtering for time-delayed linear systems

This paper is to study the linear minimum variance estimation for discretetime systems. A simple approach to the problem is presented by developing re-organized innovation analysis for the systems with instantaneous and double time-delayed measurements. It is shown that the derived estimator involves solving three different standard Kalman filtering with the same dimension as the original system. The obtained results form the basis for solving some complicated problems such as H, fixed-lag smoothing, preview control, H, filtering and control with time delays.