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Sorption of a triazol derivative by soils: importance of surface acidity

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Journal of environmental sciences 2003年第3期15卷 383-387页

作者： WU De-yi (school of environmental science and {3., Shanghai jiaotong university, Shanghai 200240, china.) school of environmental science and {3. Shanghai Jiaotong University Shanghai 200240 China

The sorption of a triazol derivative, 1-(4-chlorophenyl)- 4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl)penten-3.ol with a common name of S3.07D, on fifteen soils and three H_2O_2-treated soils was investigated. The sorption isotherm for each untreated and treated soil was non-linear, and was best fitted to Freundlich sorption equation. Soils containing high amount of clay content or organic matter or both sorbed much higher amounts of the chemical than soils that had low contents of these soil constituents. H_2O_2-treated soils showed considerable sorptive affinity for S3.07D. It was concluded that both organic matter and mineral fraction in natural soils contributed to the sorption of the basic compound. Sorption by the H_2O_2 treated soils increased as suspension pH decreased, but all suspension pHs exceeded the pKa of the compound by more than two units. This implies that organic base protonation can occur on surfaces of soil components, and surface acidity (exchangeable acidity ) is important in sorption process of the organic base rather than suspension pH.

关键词： sorption organic base soil surface acidity

A new real-time eye tracking based on nonlinear unscented Kalman filter for monitoring driver fatigue

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控制理论与应用（英文版） 2010年第2期8卷 181-188页

作者： Zutao ZHANG 1 , 2 , Jiashu ZHANG 2 (1.school of Mechanical engineering, southwest jiaotong university, {3. sichuan 61003., china 2.sichuan Key Lab of Signal and Information Processing, southwest jiaotong university, {3. sichuan 61003., china) school of Mechanical engineering Southwest Jiaotong University Chengdu Sichuan China sichuan Key Lab of Signal and Information Processing Southwest Jiaotong University Chengdu Sichuan China

A new scheme for driver fatigue detection is presented, which is based on the nonlinear unscented Kalman filter and eye tracking. Assuming a probability distribution than to approximate an arbitrary nonlinear function or transformation, eye nonlinear tracking can be achieved using an unscented transformation (UT), which adopts a set of deterministic sigma points to match the posterior probability density function of the eye movement. Driver fatigue can be detected using the percentage of eye closure (PERCLOS) framework in a realistic driving condition after the eye nonlinear tracking. This system was tested adequately in realistic driving environments with subjects of different genders, with/without glasses, in day/night driving, being commercial/noncommercial drivers, in continuous driving time, and under different road conditions. The last experimental results show that the proposed method not only improves the robustness for nonlinear eye tracking, but also can provide more accurate estimation than the traditional Kalman filter.

关键词： Eye tracking Unscented Kalman filter (UKF) Fatigue detection PERCLOS

Experimental study of CT test on the failure of acrylate spray-applied waterproof layer in the groundwater environment

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science china(Technological sciences) 2010年第2期53卷 512-518页

作者： YANG QiXin, XU Peng & ZHENG ShangFeng 1 school of Civil engineering, southwest jiaotong university, {3. 61003., china 1. school of Civil engineering Southwest Jiaotong University Chengdu 610031 China

In this study the computerized tomography (CT) was first used to quantitatively analyze the failure of acrylate spray-applied waterproof membrane in the groundwater environment. The results of the CT tests show that it is feasible to use the CT to quantitatively analyze the failure of the waterproof membrane and the CT method has the advantages of speediness and accuracy that can eliminate the fussy operation process in routine tests. The main conclusions summarized from the study are as follows. First, there are two combined-indexes that can be used to decide the failure of the spray-on waterproof layer: one is that the reduced percentage of the CT number of the spray-on waterproof layer is less than 40.0% and the other is that the variance of the CT number decreases first and then increases. Second, the applicability for the spray-on waterproof layer in the groundwater environment is the SO 24-concentration ≤ 1%, the Cl-concentration ≤ 7.5% and the pH value ≤ 12.0 of the groundwater, respectively.

关键词： spray-on waterproof layer scan CT number failure groundwater environment

Centroid-based semi-fragile audio watermarking in hybrid domain

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science china(Information sciences) 2010年第3期53卷 619-633页

作者： WANG HongXia & FAN MingQuan school of Information science and Technology, southwest jiaotong university, {3. 61003., china 1. school of Information science and Technology Southwest Jiaotong University Chengdu 610031 China

Many previous (semi-) fragile audio watermarking schemes adopt binary images as watermarks, which reduce the security of watermarking systems. On the other hand, the content-based or feature-based second generation digital watermarking has limited applicability, and its partial feature points may be damaged by watermarking operations and various common signal processing. To overcome these problems, in this paper, a novel centroid-based semi-fragile audio watermarking scheme in hybrid domain is proposed. The theoretical lower limit of signal to noise ratio (SNR) for objective evaluation of the imperceptibility of watermarked audio signal is deduced, and the watermark embedding capacity and the tamper detection ability are theoretically analyzed. In the proposed scheme, first, the centroid of each audio frame is computed, then Hash function is performed on the obtained centroid to get the watermark, after that, the audio sub-band which carries centroid of audio frame is performed with discrete wavelet transform (DWT) and discrete cosine transform (DCT), and finally the encrypted watermark bits are embedded into the hybrid domain. Theoretical analysis and experimental results show that the proposed scheme is inaudible and applicable to different types of audio signals. Furthermore, its ability of tamper detection and tolerance against common signal processing operations are excellent. Comparing with the existing schemes, the proposed scheme can effectively authenticate the veracity and integrity of audio content, and greatly expand the applicability of the content-based audio watermarking scheme.

关键词： semi-fragile audio watermarking centroid inaudibility tamper detection

Frequency/time hopping sequence sets with optimal partial Hamming correlation properties

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science china(Information sciences) 2012年第10期55卷 2207-2215页

作者： NIU XianHua 1,2,PENG DaiYuan 1 & ZHOU ZhengChun 3.1 The Provincial Key Laboratory of Information Coding and Transmission,Institute of Mobile Communications,southwest jiaotong university,chengdu 61003.,china 2 The {3. of Mathematics and Computer engineering,Xihua university,chengdu 61003.,china 3.The College of Maths,southwest jiaotong university,chengdu 61003.,china 1. The Provincial Key Laboratory of Information Coding and Transmission Institute of Mobile Communications Southwest Jiaotong University Chengdu 610031 China 2. The school of Mathematics and Computer engineering Xihua University Chengdu 610039 China 3. The College of Maths Southwest Jiaotong University Chengdu 610031 China

Frequency hopping/time hopping(FH/TH) sequences have found wide applications in various modern FH/TH spread spectrum communications,such as digital cellular mobile communication,short-range wireless communication,personal communication,and multi-user radar,sonar *** order to evaluate the goodness of FH/TH sequences design,the periodic Hamming correlation function is used as an important ***,the length of correlation window is shorter than the period of the chosen FH/TH sequence,so the study of the partial Hamming correlation of FH/TH sequence is particularly *** this paper,a new class of FH/TH sequence sets with good partial Hamming correlation properties is proposed and *** construction of new FH/TH sequence sets is based upon the generalized m-sequence and generalized Gordon-Mills-Welch sequence over a polynomial residue class *** is shown that new FH/TH sequence sets are optimal with respect to the partial Hamming correlation bound.

关键词： frequency hopping/time hopping(FH/TH) sequence partial Hamming correlation optimal FH/TH sequence set

Studies on Barriers for Promotion of Clean Technology in SMEs of china

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Chinese Journal of Population,Resources and Environment 2005年第1期3卷 9-17页

作者： Peng Sizhen , Liu Yan , Shi Han 1 2 & Zhong Ping 3.1. The Administrative Centre for china’s Agenda21, Beijing 100089, china 2. Yale school of Forestry & {3. Studies, New Haven CT 06511, the U.S.A. 3. Department of {3. science and engineering, sichuan university, chengdu sichuan 610065, china The Administrative Centre for china’s Agenda21 Beijing 100089 China Yale school of Forestry and environmental Studies New Haven CT 06511 United States Department of environmental science and engineering Sichuan University Chengdu Sichuan 610065 China

After more than 10 years efforts on awareness raising and promotion, the concept of cleaner production (CP) has been adopting as a strategic approach to balance economic benefits and environmental protection for china’s industries. However, it is also found that clean technology is difficult to be adopted and implemented in Chinese Small and Medium-sized Enterprises (SMEs) because of certain barriers. This paper investigates these barriers among three stakeholders--governments, enterprises and experts. The Analytic Hierarchy Process (AHP) was employed to prioritize the relative importance of the twenty fine-selected barriers, which were classified into four barrier categories. The findings reveal that the exterior barriers of policy and financial barriers should be stressed rather than the inner barriers of technical and managerial barriers, although they are also very important. Absence of incentives on economic policies, lax enforcement of environmental regulations and high initial capital cost were the most important barriers to adoption of Clean Technologies (CT) in china.

关键词： Cleaner Production Clean Technologies Barrier Study Small and Medium Enterprises

Semantic theory of finite lattice-valued propositional logic

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science china(Information sciences) 2010年第10期53卷 2022-2031页

作者： PAN XiaoDong 1,2 & XU Yang 2 1 school of Maths, southwest jiaotong university, chengdu 61003., {3. 2 Intelligent Control Development Center, southwest jiaotong university, chengdu 61003., {3. 1. school of Maths Southwest Jiaotong University Chengdu 610031 China2. Intelligent Control Development Center Southwest Jiaotong University Chengdu 610031 China

Based on the methodology of Pavelka’s fuzzy propositional logic, in this paper, by combining L-fuzzy set and classical two-value propositional logic theory, a kind of graded semantic theory in lattice-valued propositional logic based on finite lattice implication algebras is established. The notions of L-tautology and L-contradiction are introduced, and several theorems about the relations among different kinds of L-tautologies are given. From the viewpoint of uncertainty reasoning, the notion of satisfiability with certain level for a set of formulas is also defined. On this basis, the semantic consequence operation concerning a set of formulas is proposed, and the properties of semantic consequence operation and the consistency of fuzzy information are discussed.

关键词： lattice-valued propositional logic semantic theory L-tautology consistency lattice implication algebra

Preparation of micro-patterned surfaces of Si-N-O films and their influence on adhesion behavior of endothelial cells

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science china(Technological sciences) 2010年第1期53卷 257-263页

作者： ZHENG Nan,YANG Ping,WANG QiYi,YANG ZhongHai & HUANG Nan Key Laboratory of Advanced Technology for Materials of Education Ministry,Key Laboratory of Artificial Organ Surface engineering of sichuan,school of Materials {3. and engineering,southwest jiaotong university,chengdu 61003.,china 1. Key Laboratory of Advanced Technology for Materials of Education Ministry Key Laboratory of Artificial Organ Surface Engineering of Sichuan School of Materials Science and Engineering Southwest Jiaotong University Chengdu 610031 China

Microgrooves were prepared on Si(100) surface by photolithography and wet ***,Si-N-O films were deposited on the microgrooves by unbalanced magnetron sputtering(UBMS) and micro-patterned surfaces of Si-N-O films were *** size of the micropatterns was measured by surface *** chemical composition of Si-N-O films were characterized by X-ray photoelectron spectrometry(XPS) and the wettability of the micropatterned surfaces was evaluated by contact angle *** behavior of endothelial cells adhered on the micro-patterned surfaces,including cells adhesion,proliferation and orientation,was evaluated by cell culture test and Alamar blue *** results showed that the amount and activity of endothelial cells on micro-patterned samples were higher than those on flat *** one day's incubation,the cells were well guided along the *** days later,most of the cells grew across the grooves and contacted each *** activity was also much higher than that on flat *** was suggested that the adhesion and proliferation of endothelial cells could be effectively enhanced by micropattern method.

关键词： micropatterns Si-N-O film endothelial cell unbalanced magnetron sputtering

Analysis of Earthquake-Triggered Failure Mechanisms of Slopes and Sliding Surfaces

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Journal of Mountain science 2010年第3期7卷 282-290页

作者： WANG Jian YAO Lingkan Arshad Hussain school of Civil engineering Southwest Jiaotong University Chengdu 610031 China MOE Key Laboratory of High-speed Railway engineering Southwest Jiaotong University Chengdu 610031 China Road and Railway engineering Research Institute Sichuan Key Laboratory of Aseismic Engineering and Technology Chengdu 610031 China National university of sciences and Technology (NUST) Islamabad 44000 Pakistan

Earthquake-induced landslides along the Dujiangyan-Yingxiu highway after the Ms 8.0 Wenchuan earthquake in 2008 were investigated. It was found that：（1） slopes were shattered and damaged during the earthquake and open tension cracks formed on the tops of the slopes; （2） the upper parts of slopes collapsed and slid, while the lower parts remained basically intact, indicating that the upper parts of slopes would be damaged more heavily than the lower parts during an earthquake. Large-scale shaking table model tests were conducted to study failure behavior of slopes under the Wenchuan seismic wave, which reproduced the process of deformation and failure of slopes. Tension cracks emerged at the top and upper part of model, while the bottom of the model remained intact, consistent with field investigations. Depth of the tension crack at the top of model is 3. cm, i.e., 3.2 m compared to the prototype natural slope with a height of 14 m when the length scale ratio （proto/model） is lo. Acceleration at the top of the slope was almost twice as large as that at the toe when the measured accelerations on shaking table are 4.85 m/s2 and 6.49 m/s2, which means that seismic force at the top of the slope is twice the magnitude of that at the toe. By use of the dynamic-strength-reduction method, numerical simulation was conducted to explore the process and mechanism of formation of the sliding surface, with other quantified information. The earthquake-induced failure surfaces commonly consist of tension cracks and shear zones. Within 5 mfrom the top of the slope, the dynamic sliding surface will be about 1 m shallower than the pseudo-static sliding surface in a horizontal direction when the peak ground acceleration （PGA） is 1 m/s2; the dynamic sliding surface will be about 2 m deeper than the pseudo-static sliding surface in a horizontal direction when the PGA is lo m/sL and the depths of the dynamic sliding surface and the pseudo-static sliding surface will be almost the sam

关键词： Subgrade engineering slope failuremechanism shaking table model test: seismicsliding surface Wenchuan earthquake