Showing papers in "Journal of South China University of Technology in 2000"

Influence of Microwave on the Ultrastructure of Cellulose I

Abstract: Examined in this study is the variation of crystallinity and crystal plane size of water_swelled cellulose Ⅰ treated by microwave The results from FTIR show that there is no effect of microwaves on the chemical structure of cellulose, but its N_O′KI increases Moreover, the results from WAXD indicate that cellulose Ⅰ still contains noncrystalline and crystalline regions after microwave treating, but its crystallinity and crystal face dimension increase When the microwave power is greater than 128 W and the treating times higher than 4, their effects on crystallinity and crystal face dimension of cellulose are much less

A New Fuzzy Control Method for Isolated Intersection Traffic Management

Abstract: Intelligent control is an inevitable trend of urban traffic management and fuzzy control is one of its effective methods. In this article an attempt is made to apply fuzzy control to urban traffic system by proposing a new concept of link vehicle in designing the fuzzy controller. The effectiveness of this method was simulated on a single intersection. The experimental results show that the proposed fuzzy logic controller outperforms the existing controllers in terms of the average delay of vehicles as well as the queue length.

Optimization on the Highly Accuracy Equal Strength Beam for Calibration

Abstract: According to the theory of uncertainty, optimization on the highly accuracy equal strength beam for calibration has been investigated. The optimum design method and parameters have been determined. The optimal result has been proved in the test.

Construction of the Adjoining Relationship of STL Files and the Study on Slicing Algorithm

Abstract: By the analysis of the structures of STL files and based on the structure of undiagraph, the adjoining relationship among the triangles is constructed by which one can search for a triangle and slice easily A slicing algorithm is studied and the problems which may happen during the slicing process are discussed Some methods to solve the problems are proposed too At last, a Double Link List is used to express the CAD mold after slicing

An Improvement on Hardy's Inequality in [2, 5]

Abstract: In the interval p ∈[2, 5], 1/ p +1/ q =1, we build a strengthened Hardy's inequality: ∞ n =11 n  n k =1 a k p q p ∞ n =11-138 n 1/ q a p n .

The Choice of Wavelet Bases for Singular Signal Detection

Abstract: Singular signal always brings some important information in the diagnosis field and wavelet is an useful tool to detect singularity. Several wavelets' effect on singularity detection is analyzed and compared with each other in this paper. Based on these results, the best wavelet base is recommended according to the characteristic of different singular signal. And the cutting force signal, which is the singular signal when the tool is worn, is used to test the performance of these wavelet bases.

Position Invariant Pattern Recognition of Retinal Blood Vessels Based on the Branch-Removal Tracing for Feature Extraction

Abstract: Some new methods and improved approaches are presented in the research of position invariant pattern recognition for retinal blood vessels, including adaptive gray level correction in image pre_processing, chain code extraction based on branch_removal tracing in mesh image with connected branch and position invariant pattern recognition by means of the criterion of minimum distance error, the experimental results are also showed

Research on Color Image Quantization Methods

Abstract: Color image quantization is one of the key technologies in image processing In this paper, several current color quantization algorithms are discussed and a new statistically clustering algorithm is proposed It is shown through experiments that this algorithm has good performance and low complexity for color image quantization

A New Fast Algorithm for Computing Prime-length DCT Through Cyclic Convolutions

Abstract: This paper proposes a new algorithm for the computation of Discrete Cosine Transform (DCT) with odd prime length using cyclic or skew cyclic convolutions. The algorithm separates DCT coefficients into three parts: DC coefficients, even and odd indexed DCT coefficients. According to the number theory a new index mapping operation is defined. By means of the index mapping operation,the even indexed part is converted to a cyclic convolution, and the odd indexed part is converted to a cyclic or skew cyclic convolution depending on its length. Since efficient and fast cyclic convolution algorithms are available in the literature, the algorithm has low computational complexity, simple and regular structure.

Influence and Control of Metal Ions: An Investigation into High Temperature Peroxide Bleaching

Abstract: Transition metal ions play an important role in high temperature hydrogen peroxide bleaching Manganese decreased the pulp brightness quite significantly without decreasing the viscosity Copper did not have a big impact on the brightness, but it decreased the viscosity obviously The addition of both ferric and ferrous to the pulp did not affect the brightness obviously, but caused a decrease in the viscosity Three different strategies (QP, AP and (AQ)P) can be used to control the metal profile in the pulp A brightness of 81 +% ISO can be achieved using the (AQ)P sequence with 4% hydrogen peroxide

A Tentative Study of Wave-Making Equipment and Wave Simulated Technology in the Laboratory

Abstract: This paper discusses the wave_making system and its characteristics as well as the application of this system to model tests in the laboratory. The standards of inspection and the methods of simulating wave are also presented. The test results in the flume indicate that the system can simulate waves correctly. In the regular wave experiment, the transverse error of wave height is less than 2% , the repeated error of the wave height is less than 1.28% and the period repeated error is less than 0.2%. In the non_regular wave experiment, the average wave height error is less than 4.87%, the average pariod error is less than 4.59%, while the repeated error of the wave height is less than 1.87% and the transverse error of wave height is less than 3 71%. The wave spectrum simulated are perfect and can meet the requirement of wave model tests.

The Random Noise Removal of the Corrupted Image Based on Fuzzy Technique

Abstract: Based on the results of a former article by the same authors, an Iterative Fuzzy Median Filter (IFMF) is presented in this paper. IFMF is used to change the random noise image into the salt_pepper noise image and FDWM is used to remove the noise, so that FDWM can be used to remove multinoise for image.

Overall Evaluation of the Living and Environmental Quality in Residential Area

Abstract: The living and environmental quality of 17 residential quarters in Hangzhou, Xiamen , Nanjing and Wenzhou was investigated. 1 297 persons were surveyed. A data base was established to store survey data, and multivariate analyses were made. The order of the importance of the 10 factors judged by respondents is the first—safety and pollution prevention, the second—physical environment, shops and public living services , the third—public transport and sanitation, the fourth—green spaces, schools and entertainments, and the last—appearance and location. This shows that residents have a tendency of giving stronger weight to those factors which are rated as dissatisfaction. The weighting vector for 10 factors was obtained by making an analytic hierarchy process, and then the overall evaluations for the living and environmental quality of the residential area were made by fuzzy set theory.

Nonlinear Vibration of a Rectangular Plate with Physical Nonlinearity

Abstract: The objective of this paper is to study the vibration of a rectangular plate pined at the edges. The effects of the physical nonlinearity and static deformation on the dynamic characteristics are taken into consideration. Using the Galerkin principle, the nonlinear dynamic equation for the unknown function varied only with time and its closed-form solution can be obtained. Finally, the discussion is given.

Research on the application of impact compaction technology in rehabilitating engineering of old cement concrete pavement

Abstract: For the first time, impact compactor with polygon roller for breaking up and compacting old cement concrete pavement slab in rehabilitating engineering of old cement concrete pavement. This paper takes this site application as an example and discusses the compaction mechanism and effect of the Compactor. The results show that the Impact Compactor is effective for breaking up and compacting the old slab. Consequently additional vertical displacement arisen from the old slab that was separated from road base before would be settled down and modulus of resilience for the base course top was improved. Especially, the all-around effect of the Compactor would be better when the road base is unstable but its moisture content is adequate.

Study on Global Optimization Algorithms for Complex Engineering Problem

Abstract: GA, SA and NN are extensively used on the global optimization of complex engineering problems. Their characteristics and abilities of global optimization are introduced in the paper. It also discusses how to improve their effect according to t their advantages and faults and analyses how to deal with the object function and constraints—the key techniques of the complex engineering problem optimization. Finally, the future developments of the global optimization algorithm and the optimization design of complex engineering problems are proposed.

Enhancement of Lipase-catalysed Esterification in Organic Solvent by Ultrasonic Irradiation

Abstract: The enhancement of lipase_catalysed esterification of organosily alcohol with fatty ester in organic solvent by ultrasonic irradiation was explored.The effects of ultrasonic irradiation power, the manner of ultrasonic irradiation, the chain length of fatty acid and water activity in the reaction system on this enhancement were all systematically investigated. It was shown that suitable ultrasonic irradiation could enhance the lipase_catalysed esterification reaction in organic solvent. The longer the chain length of the substrate or the higher the water activity of the reaction system, the more apparent the enhancement.

Inductive Learning of Fuzzy Classification Rules for Machine Fault Diagnosis

Abstract: For ensuring the machines operating in a safe situation and improving the productivity, reliably monitoring the machine condition is becoming necessary and important in automatic ma_nufacturing systems. Due to high uncertainties inherent in industrial environment, the reliability of the developed fault diagnostic systems is still unsatisfactory. Extensive research has been performed to develop fuzzy diagnosis system for handling the problems related to the uncertainties. In the design of a fuzzy classification system, the most important task is to extract a set of fuzzy rules related to a particular problem. This paper presents a new inductive learning method, termed as fuzzy inductive learning, for extracting fuzzy classification rules from a set of numerical training data. In this paper, an alternative criterion is proposed for the induction of fuzzy decision trees by measuring the information gain in the possibility domain. The effectiveness of the proposed fuzzy inductive learning method has been illustrated in extracting a set of fuzzy rules for a machine diagnostic system that is worked in a highly uncertain situation. The experimental results show that the generated fuzzy rules can classify the machine conditions with high accuracy.

Assessment and Analysis of the Productive Technical Efficiency of the Construction Industry in China

Abstract: This paper proposes an econometric model from the non-parametric approach to conduct a quantitative analysis of the productive technical efficiency of the construction industry in China from 1981 to 1996. The result shows that the technical efficiency has been improved significantly with an average growth rate of 10. 06% during the observation period. The econometric approach provides some guidelines for other researches in economic productivity.

An Approach to Some Statistical Properties of Chaotic Attractors

Abstract: Presented in this paper is a new approach to some statistical properties of chaotic attractors on the basis of the cell model of chaotic attractors. The approach can give histograms for different types of periodic orbits and provide detailed description and main parameters of a chaotic attractor. The information obtained is useful in finding hot sub attractors and the differences among the chaotic attractors. Besides, the histograms for chaotic attractors of Rossler's equation and Chua's circuit are given respectively.

Optimization for Coach Station Service Capacity Distribution

Abstract: In a large city there are usually several coach stations for passenger transportation. How to distribute the service capacity and the origin_destination stations, especially in the case of adding some new stations and how to adjust service capacity, dispatch service route constitute the main problems confronting the transportation management departments and transportation enterprises. Based on the demand of passenger transportation in Changchun coach station system planning, the optimal theory is applied to the distribution of the forecasted demand to each coach service route and a detail theoretical solution for the service capacity distribution is presented.

The Action and its Control of Metal Ions on Pulp Oxygen Bleaching

Abstract: The metal ions in pulp result from material ,equipment , water and additional chemical agents The transition metal ions, such as Cu 2+ 、 Fe 3+ 、 Mn 2+ , not only effect the brightness of unbleached pulp, but also catalyze the radical reaction during oxygen bleaching With the poor selectivity, hydroxy radicals would cause an obvious degradation of carbohydrates,and decrease the strength and viscosity of oxygen bleached pulp On the other hand , Mg 2+ can protect the carbohydrates from degradation,but at the same time ,it could stabilize the lignin By means of pretreatment with sulfuric acid or chelating agents, we can lower the influence of the transition ions on oxygen bleaching of pulp

Solubility of Sediment in Soy Sauce

Abstract: The main composition in sediment of soy sauce and the solubility of these compounds at different pH were studied. It is found that all sediments contain insoluble inorganic compounds, the solubility of saccharides is very high, the solubility of proteins in sediment appear low at low pH and high at high pH, and at pH5 the clear solution of extract of first sediment become haze. The cause and the mechanism of sediment of soy sauce are probed.

The Automatic Following Optical-Axis of Fuzzy Control in the Automobile Headlight Tester

Abstract: By studying the automatic following optical axis in the automobile headlight tester, this paper presents a method which may control the process of the automatic following optical axis in the automobile headlight tester by means of fuzzy control. The experiment shows that not only the speed of testing but also the accuracy of the measurement results have been greatly improved in the automobile headlight tester. This control method clears up the oscillation which may occur in the automatic following process, thus making the automatic following process faster and more accurate.

Temperature Measurement by Thermocouple in a Microwave Field

Abstract: It was found that there was a distinct response fluctuation when temperature was measured by thermocouple in a microwave field Further experiments showed that such fluctuation was related to the action of microwave and the measurement intervals Proposed in this paper is a method of proper temperature measurement by thermocouple during microwave irradiation and the relevant mechanism is also elucidated

Microbial Biochemical Reactions of Anaerobic Oxidation of Ammonium

Abstract: Based on McCarty's half reaction concept and Zhou's method, the stoichiometric equations of anaerobic oxidation of ammonium (AOA) are yielded. It is discovered that AOA process is a kind of autotrophic bioprocess. There are two possibilities of the nitrogen source for cell synthesis of AOA, i.e., NO - x or NH + 4. The alkalinity is necessary for AOA process when NH + 4 is used as the nitrogen source for cell synthesis. It is predicted that pH values will decrease if AOA processes are achieved.

Improvement of High Dimensional Gronwall-Bihari Type Discrete Inequalities Involving Infinite Sums

Abstract: In this paper, the n _dimensional Gronwall_Bihari type discrete inequalities involving infinite sums are studied. Some estimations on the upper bounds of the solutions of the above inequalities are obtained.

Numerical Analyses of the Stress Field on the interface Between Fiber Sheet and Concrete Member

Abstract: The stress field on the interface between fiber-sheet and concrete member in a carbon fiber-sheet-reinforced concrete 3-P bending specimen with a V-notch is analyzed by FEM, the relationship of two stress fields on the interface and the V-notch tip, and the effects of debonding length on the stress fields are also discussed The analysis results show that a new stress concentration on the interface has arisen,and the strength of the member is determined by that of the interface while the bonding is intact,but the debonding length is a key factor for the strength while the local debonding has taken place

The Effect of Oil Contamination on the Velocity_Load Characteristic of the Throttle Velocity-Modulating Circuits

Abstract: This paper analyses the effect of the solid particle contaminant on the velocity_load characteristic of three hydraulic velocity_modulating circuits by experiments. It provides a contrast of this effect on the three circuits. The study indicates that different size particle contaminants have different effects on the velocity_load characteristic. The present research is of practical significance in designing and using the throttle velocity modulating circuit.