期刊文献+
共找到14,939篇文章
< 1 2 250 >
每页显示 20 50 100
Relationships between humic substance-bound mercury contents and soil properties in subtropical zone 被引量:2
1
作者 YU Gui-fen WU Hong-tao +2 位作者 JIANG Xin HE Wen-xiang QING Chang-le 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第5期951-957,共7页
The bioavailability of humic substance-bound mercury (HS-Hg) has been established, while the distribution of HS-Hg in soils in relation to soil properties remains obscure. Path analysis and principal component analy... The bioavailability of humic substance-bound mercury (HS-Hg) has been established, while the distribution of HS-Hg in soils in relation to soil properties remains obscure. Path analysis and principal component analysis were employed in present study to investigate how soil factors influence the contents of HS-Hg in soils. Results showed that HS-Hg ranged from 0.0192 to 0.2051 mg/kg in soils. The two fractions existed in soils as humic acid-bound mercury (HA-Hg) 〉 fulvic acid-bound mercury (FA-Hg) and the ratio of HA-Hg/FA-Hg was 1.61 on the average. Soil organic carbon (OC) and HS favorably determined soil HS-Hg and the two fractions. The mercury source forming HS-Hg derived from soil total mercury and HS-Hg. FA-Hg and HA-Hg served as mercury source for each other. In acidic soils, FA-Hg and HA-Hg consistently rose with the increase of OC, and generally HA-Hg increased more dramatically. Soils with lower pH and lighter texture contained more HS-Hg, particularly fraction of FA-Hg. Among all influencing factors, organic material source showed the strongest effect, followed by other soil properties and soil mercury source. 展开更多
关键词 humic acid-bound Hg fulvic acid-bound Hg soil properties
下载PDF
Interval analysis method and convex models for impulsive response of structures with uncertain-but-bounded external loads 被引量:7
2
作者 Zhiping Qiu Xiaojun Wang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2006年第3期265-276,共12页
Two non-probabilistic, set-theoretical methods for determining the maximum and minimum impulsive responses of structures to uncertain-but-bounded impulses are presented. They are, respectively, based on the theories o... Two non-probabilistic, set-theoretical methods for determining the maximum and minimum impulsive responses of structures to uncertain-but-bounded impulses are presented. They are, respectively, based on the theories of interval mathematics and convex models. The uncertain-but-bounded impulses are assumed to be a convex set, hyper-rectangle or ellipsoid. For the two non-probabilistic methods, less prior information is required about the uncertain nature of impulses than the probabilistic model. Comparisons between the interval analysis method and the convex model, which are developed as an anti-optimization problem of finding the least favorable impulsive response and the most favorable impulsive response, are made through mathematical analyses and numerical calculations. The results of this study indicate that under the condition of the interval vector being determined from an ellipsoid containing the uncertain impulses, the width of the impulsive responses predicted by the interval analysis method is larger than that by the convex model; under the condition of the ellipsoid being determined from an interval vector containing the uncertain impulses, the width of the interval impulsive responses obtained by the interval analysis method is smaller than that by the convex model. 展开更多
关键词 Impulsive response Interval analysis method Convex model Uncertain-but-bounded impulse
下载PDF
Weekly albumin-bound paclitaxel/cisplatin versus gemcitabine/cisplatin as first-line therapy for patients with advanced non-small-cell lung cancer:A phase II open-label clinical study 被引量:9
3
作者 Shanshan Qin Hui Yu +10 位作者 Xianghua Wu Zhiguo Luo Huijie Wang Si Sun Mingzhu Huang Jia Jin Zhonghua Tao Jie Qiao Yu Feng Jialei Wang Jianhua Chang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2019年第2期339-348,共10页
Objective: The aim of this trial was to compare both the efficacy and the safety of a weekly nanoparticle albumin-bound paclitaxel(nab-paclitaxel) plus cisplatin vs. gemcitabine plus cisplatin in patients with advance... Objective: The aim of this trial was to compare both the efficacy and the safety of a weekly nanoparticle albumin-bound paclitaxel(nab-paclitaxel) plus cisplatin vs. gemcitabine plus cisplatin in patients with advanced non-small-cell lung cancer(NSCLC).Methods: A total of 84 participants received either 100 mg/m^2 nab-paclitaxel each week on d 1, 8 and 15 of a 28 day cycle, as well as cisplatin 75 mg/m^2 on d 1 every three weeks(nab-TP arm); or gemcitabine 1,000 mg/m^2 on d 1 and 8, plus cisplatin 75 mg/m^2 on d 1 every three weeks(GP arm). The primary end point was progression-free survival(PFS). The secondary end points were overall response rate(ORR) and overall survival(OS).Results: According to our analysis, the median PFS was 4.8 months for the nab-TP arm vs. 5.2 months for the GP arm(P=0.55). Analysis showed the median OS was 14.6 months for participants who were in the nab-TP arm vs. 15.1 months for those in the GP arm(P=0.94). Besides, nab-TP showed OS advantages over GP in patients harboring epidermal growth factor receptor(EGFR) mutation(26.7 vs. 15.3 months, P=0.046) and patients with a performance status of 0(23.5 vs. 14.7 months, P=0.020). It was found that incidences of drug-related grade 3 or 4 toxicities were comparable between the two treatment arms.Conclusions: Therefore, it can be seen that weekly nab-TP treatment has a similar efficacy and tolerability to GP treatment for patients who are undergoing their first-line treatment for NSCLC. It could be that survival differences among platinum doublets in the context of both EGFR mutation and performance status have the potential to be the basis for our further clinical trials. 展开更多
关键词 Albumin-bound paclitaxel CISPLATIN GEMCITABINE FIRST-LINE therapy ADVANCED non-small-cell lung cancer
下载PDF
Weekly intravenous nanoparticle albumin-bound paclitaxel for elderly patients with stage IV non-small-cell lung cancer:a series of 20 cases 被引量:7
4
作者 Qi Zheng Yu Yao Kejun Nan 《The Journal of Biomedical Research》 CAS 2012年第3期159-164,共6页
The purpose of this study was to evaluate the efficacy and safety of nanoparticle albumin-bound paclitaxel as a rescue regimen in the treatment of patients with advanced non-small-cell lung cancer. We retrospectively ... The purpose of this study was to evaluate the efficacy and safety of nanoparticle albumin-bound paclitaxel as a rescue regimen in the treatment of patients with advanced non-small-cell lung cancer. We retrospectively reviewed the medical records of 20 patients with stage IV non-small-cell lung cancer. The patients had progressive disease after standard antitumor therapy and subsequently received intravenous albumin-bound paclitaxel at the dose of 100 mg/m2 in weekly schedule. Cumulative findings showed that the overall response rate was 30.0%, the disease control rate amounted to 40%, and the 1 year survival rate was 30%. In addition, the median time to progression and the median survival time reached 5 and 10 months, respectively. Meanwhile, no severe hypersensitivity reactions and grade 4 adverse effects were reported. In summary, weekly-administered albumin-bound paclitaxel seems to be an effective and safe regimen for elderly patients with stage IV non-small-cell lung cancer who were refractory to conventional therapy. 展开更多
关键词 non-small-cell lung cancer nanoparticles albumin-bound PACLITAXEL
下载PDF
Finite-time control of linear parameter-varying systems with norm-bounded exogenous disturbance 被引量:5
5
作者 Yanjun SHEN 《控制理论与应用(英文版)》 EI 2008年第2期184-188,共5页
In this paper, a new approach is presented for finite-time control problems for linear systems subject to time-varying parametric uncertainties and exogenous disturbance. The disturbance is assumed to be time varying ... In this paper, a new approach is presented for finite-time control problems for linear systems subject to time-varying parametric uncertainties and exogenous disturbance. The disturbance is assumed to be time varying and bounded. Sufficient conditions are obtained for the existence of a linear parameter-dependent state feedback gain, which can ensure that the closed-loop system is finite-time bounded (FTB). The conditions can be reduced to feasibility problems involving LMIs. Numerical examples show the validity of the proposed methodology. 展开更多
关键词 Finite time stability Polytopic system LMI Norm-bounded exogenous disturbance
下载PDF
Decentralized robust H-infinity descriptor output feedback control for value-bounded uncertain descriptor large-scale systems 被引量:6
6
作者 Yongfang XIE Weihua GUI Zhaohui JIANG 《控制理论与应用(英文版)》 EI 2006年第2期193-200,共8页
For a class of value-bounded uncertain descriptor large-scale interconnected systems, the decentralized robust H∞ descriptor output feedback control problem is investigated. A design method based on the bounded real ... For a class of value-bounded uncertain descriptor large-scale interconnected systems, the decentralized robust H∞ descriptor output feedback control problem is investigated. A design method based on the bounded real lemma is developed for a decentralized descriptor dynamic output feedback controller, which is reduced to a feasibility problem for a nonlinear matrix inequality (NLMI). It is proposed to solve the NLMI iteratively by the idea of homotopy, where some of the variables are fixed alternately at each iteration to reduce the NLMI to a linear matrix inequality (LMI). A given example shows the efficiency of this method . 展开更多
关键词 Descriptor output feedback Value-bounded uncertainty Decentralized H-infinity control Homotopy method LMI
下载PDF
Combined influence of nonlinearity and dilation on slope stability evaluated by upper-bound limit analysis 被引量:6
7
作者 TANG Gao-peng ZHAO Lian-heng +1 位作者 LI Liang CHEN Jing-yu 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第7期1602-1611,共10页
The combined influence of nonlinearity and dilation on slope stability was evaluated using the upper-bound limit analysis theorem.The mechanism of slope collapse was analyzed by dividing it into arbitrary discrete soi... The combined influence of nonlinearity and dilation on slope stability was evaluated using the upper-bound limit analysis theorem.The mechanism of slope collapse was analyzed by dividing it into arbitrary discrete soil blocks with the nonlinear Mohr–Coulomb failure criterion and nonassociated flow rule.The multipoint tangent(multi-tangent) technique was used to analyze the slope stability by linearizing the nonlinear failure criterion.A general expression for the slope safety factor was derived based on the virtual work principle and the strength reduction technique,and the global slope safety factor can be obtained by the optimization method of nonlinear sequential quadratic programming.The results show better agreement with previous research result when the nonlinear failure criterion reduces to a linear failure criterion or the non-associated flow rule reduces to an associated flow rule,which demonstrates the rationality of the presented method.Slope safety factors calculated by the multi-tangent inclined-slices technique were smaller than those obtained by the traditional single-tangent inclined-slices technique.The results show that the multi-tangent inclined-slices technique is a safe and effective method of slope stability limit analysis.The combined effect of nonlinearity and dilation on slope stability was analyzed,and the parameter analysis indicates that nonlinearity and dilation have significant influence on the result of slope stability analysis. 展开更多
关键词 slope stability ANALYSIS nonlinear failure criterion non-associated flow rule multipoint TANGENT technique upper-bound limit ANALYSIS THEOREM
下载PDF
Vertex solution theorem for the upper and lower bounds on the dynamic response of structures with uncertain-but-bounded parameters 被引量:4
8
作者 Zhiping Qiu Xiaojun Wang Institute of Solid Mechanics, Beihang University, 100083 Beijing, China 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第3期367-379,共13页
The aim of this paper is to evaluate the effects of uncertain-but-bounded parameters on the dynamic response of structures. By combining the interval mathematics and the finite element analysis, the mass matrix, dampi... The aim of this paper is to evaluate the effects of uncertain-but-bounded parameters on the dynamic response of structures. By combining the interval mathematics and the finite element analysis, the mass matrix, damping matrix, stiffness matrix and the external loads are represented as interval matrices and vector. With the help of the optimization theory, we present the vertex solution theorem for determining both the exact upper bounds or maximum values and the exact lower bounds or minimum values of the dynamic response of structures, in which these parameters reach their extreme values on the boundary of the interval mass, damping, stiffness matrices and the interval extemal loads vector. Three examples are used to illustrate the computational aspects of the presented vertex solution theorem. 展开更多
关键词 Dynamic response Vertex solution theorem Uncertain-but-bounded parameters
下载PDF
The spanwise spectra in wall-bounded turbulence 被引量:3
9
作者 Hong-Ping Wang Shi-Zhao Wang Guo-Wei He 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2018年第3期452-461,共10页
The pre-multiplied spanwise energy spectra of streamwise velocity fluctuations are investigated in this paper. Two distinct spectral peaks in the spanwise spectra are observed in low-Reynolds-number wall-bounded turbu... The pre-multiplied spanwise energy spectra of streamwise velocity fluctuations are investigated in this paper. Two distinct spectral peaks in the spanwise spectra are observed in low-Reynolds-number wall-bounded turbulence. The spectra are calculated from direct numerical simulation (DNS) of turbulent channel flows and zero-pressure-gradient boundary layer flows. These two peaks locate in the nearwall and outer regions and are referred to as the inner peak and the outer peak, respectively. This result implies that the streamwise velocity fluctuations can be separated into large and small scales in the spanwise direction even though the friction Reynolds number Rer can be as low as 1000. The properties of the inner and outer peaks in the spanwise spec- tra are analyzed. The locations of the inner peak are invariant over a range of Reynolds numbers. However, the locations of the outer peak are associated with the Reynolds number, which are much higher than those of the outer peak of the pre-multiplied streamwise energy spectra of the streamwise velocity. 展开更多
关键词 Wall-bounded turbulence Streamwise/spanwise spectra Scale separation Inner/outer peak
下载PDF
Efficacy and safety of albumin-bound paclitaxel in treating recurrent advanced non-small-cell lung cancer 被引量:2
10
作者 Pu-Yuan Xing Jun-Ling Li +5 位作者 Yan Wang Xue-Zhi Hao Bin Wang Lin Yang Yuan-Kai Shi Xiang-Ru Zhang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2013年第2期200-205,共6页
Objective: To observe the efficacy and safety of albumin-bound paclitaxel (ABP) monotherapy in treating recurrent advanced non-small-cell lung cancer (NSCLC). Methods: We retrospectively analyzed the short-term ... Objective: To observe the efficacy and safety of albumin-bound paclitaxel (ABP) monotherapy in treating recurrent advanced non-small-cell lung cancer (NSCLC). Methods: We retrospectively analyzed the short-term efficacy and toxicities of ABP monotherapy in treating 21 patients who had previously undergone multiple cycles of therapy for their advanced NSCLC in our hospital since 2010. The treatment-related survival was also analyzed. Results: Of these 21 patients, the best overall response was partial response (PR) in 6 patients (28.6%), stable disease (SD) in I0 patients (47.6%), and progressive disease (PD) in 5 patients (23.8%). The overall response rate (ORR) was 28.6% and the disease control rate (DCR) (PR + SD) was 76.2%. The median progression-flee survival (PFS) was 4.0 months (95% CI, 5.0-7.0 months). The main grade 3/4 toxicities included neutropenia (11.1%), peripheral nerve toxicity (5.6%), muscle and joint aches (5.6%), and fatigue (5.6%). Conclusions: The ABP monotherapy can achieve good objective response in advanced NSCLC patients who have previously received multiple cycles of treatment and be well tolerated. 展开更多
关键词 Albumin-bound paclitaxel PACLITAXEL advanced non-small cell lung cancer CHEMOTHERAPY
下载PDF
Lower Bounds and a Nearly Fastest General Parallel Branch-and-Bound Algorithm 被引量:2
11
作者 Wu, Jigang Xie, Xing +1 位作者 Wan, Yingyu Chen, Guoliang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2000年第3期65-73,共9页
In this paper, it is supposed that the B&B algorithm finds the first optimal solution after h nodes have been expanded and m active nodes have been created in the state-space tree. Then the lower bound Ω(m+h log ... In this paper, it is supposed that the B&B algorithm finds the first optimal solution after h nodes have been expanded and m active nodes have been created in the state-space tree. Then the lower bound Ω(m+h log h) of the running time for the general sequential B&B algorithm and the lower bound Ω(m/p+h log p) for the general parallel best-first B&B algorithm in PRAM-CREW are proposed, where p is the number of processors available. Moreover, the lower bound Ω(M/p+H+(H/p) log (H/p)) is presented for the parallel algorithms on distributed memory system, where M and H represent total number of the active nodes and that of the expanded nodes processed by p processors, respectively. In addition, a nearly fastest general parallel best-first B&B algorithm is put forward. The parallel algorithm is the fastest one as p = max{hε, r}, where ε = 1/ rootlogh, and r is the largest branch number of the nodes in the state-space tree. 展开更多
关键词 BRANCH-AND-bound State-space tree Active list Parallel algorithm Combinatorial search.
下载PDF
Geochemical Behaviors of REE and Other Trace Elements during the Formation of Strata-bound Skarns and Related Deposits:A Case Study of the Dongguashan Cu(Au)Deposit,Anhui Province,China 被引量:1
12
作者 LINGQicong LIUCongqiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2003年第2期246-257,共12页
REE and other trace elements in the altered marbles, massive skarns and ores, as well as garnet and quartz were determined in order to examine the behaviors of trace elements during hydrothermal alteration. It is demo... REE and other trace elements in the altered marbles, massive skarns and ores, as well as garnet and quartz were determined in order to examine the behaviors of trace elements during hydrothermal alteration. It is demonstrated that the high-field-strength (HFS) elements Zr, Hf, Th and Nb were immobile while other trace elements were mobile during the formation of skarns and related deposits. REE and ore-forming elements such as Cu and Ag in hydrothermally-altered marbles and skarns were provided primarily by hydrothermal fluids. In the direction transverse of the strata, the more deeply the marbles were altered, the higher the total REE abundance and the larger the negative Eu anomalies would be. The chondrite-normalized REE patterns of skarns are similar to those of the marbles, but the former are distinguished by much higher REE contents and more remarkable negative Eu anomalies. Those patterns were apparently not inherited from the marble protolith, but were controlled by garnets, which were determined by the hydrothermal solutions involved in the infiltration metasomatism. The hydrothermal fluids are characterized by having slightly right-hand dipping REE patterns, being enriched in LREE and having strongly negative Eu anomalies. The uptake of REE from hydrothermal fluids during the growth of garnet crystals resulted in the garnets having similar REE patterns to the hydrothermal fluids. Based on the spatial variation of REE in skarns and the structures of the hosting strata, we can get a better understanding of the transport path and pattern of the fluids involved in the formation of skarns and their related deposits. REE geochemistry investigation can help elucidate the genesis of skarns and skarn-related deposits. 展开更多
关键词 trace element geochemistry REE strata-bound skarn Dongguashan deposit Anhui China
下载PDF
A branch-and-bound algorithm for multi-dimensional quadratic 0-1 knapsack problems 被引量:2
13
作者 孙娟 盛红波 孙小玲 《Journal of Shanghai University(English Edition)》 CAS 2007年第3期233-236,共4页
In this paper, a branch-and-bound method for solving multi-dimensional quadratic 0-1 knapsack problems was studied. The method was based on the Lagrangian relaxation and the surrogate constraint technique for finding ... In this paper, a branch-and-bound method for solving multi-dimensional quadratic 0-1 knapsack problems was studied. The method was based on the Lagrangian relaxation and the surrogate constraint technique for finding feasible solutions. The Lagrangian relaxations were solved with the maximum-flow algorithm and the Lagrangian bounds was determined with the outer approximation method. Computational results show the efficiency of the proposed method for multi-dimensional quadratic 0-1 knapsack problems. 展开更多
关键词 multi-dimensional quadratic 0-1 knapsack problem branch-and-bound method Lagrangian relaxation outer approximation surrogate constraint.
下载PDF
基于语料库的类词缀“-bound”构词分析与语义考察
14
作者 陈佳楠 张令千 《英语广场(学术研究)》 2019年第10期64-66,共3页
英语类词缀是一类处于自由词素和典型词缀之间定义模糊的特殊词缀,往往具有很强的构词能力,但因为词缀的差异性及其变化的时代性,许多构词力强的词缀实际出现的频率并不高。本文从美国权威英语语料库中提取N-bound结构的相关语料,主要... 英语类词缀是一类处于自由词素和典型词缀之间定义模糊的特殊词缀,往往具有很强的构词能力,但因为词缀的差异性及其变化的时代性,许多构词力强的词缀实际出现的频率并不高。本文从美国权威英语语料库中提取N-bound结构的相关语料,主要对其构词和语义特征两个方面进行探究。本文认为,类词缀“-bound”的构词能力较强,历年的构词频率处于基本稳定的状态。从语义学角度看,与“-bound”搭配的第二成分词性多为名词;“-bound”的语义是由自由词“bound”的两种语义“正在到……去的”与“约束/限制”演化而成的。 展开更多
关键词 类词缀 "-bound" 语料库 构词频率 语义特征
下载PDF
A geochemical investigation of the free and carbonate-bound organic matter in the clay-sized fraction of argillaceous source rocks and its significance for biogenic interpretation 被引量:1
15
作者 Yue Zhao Jin-Gong Cai +1 位作者 Tian-Zhu Lei Yan Yang 《Petroleum Science》 SCIE CAS CSCD 2018年第4期681-694,共14页
The molecular composition and biomarker distribution of various occurrences of organic matter in argillaceous source rocks developed in fresh and saline lacustrine environments were revealed by successive treatments o... The molecular composition and biomarker distribution of various occurrences of organic matter in argillaceous source rocks developed in fresh and saline lacustrine environments were revealed by successive treatments of solvent extraction followed by acid hydrolysis using gas chromatography–mass spectrometry. The free fraction obtained by solvent extraction provided abundant geochemical information concerning the sedimentary environment, thermal maturity and biogenic origin, and obvious differences existed between fresh and saline lacustrine source rock samples. Our research results indicate that the carbonate-mineral-bound(CM-bound) fraction released by successive acid hydrolysis could also serve as a significant biogenic indicator, as the bicyclic sesquiterpenoids, indicative of Botryococcus braunii origin, were specifically detected in quite high abundance in the acid-soluble fraction. In addition, the light end hydrocarbons were much better preserved in the acid-soluble fraction, and elemental sulfur was only detected in the CM-bound fraction, suggesting a relatively confined environment for the CM-bound fraction, which thus could preserve additional geochemical information compared to that of the free fraction. The CM-bound fraction also exhibited discernable differences between fresh and saline lacustrine samples. Therefore, it can be concluded that comprehensive analysis of free and CM-bound fractions in the argillaceous source rocks can provide a more authentic and objective interpretation of geologic conditions. 展开更多
关键词 Argillaceous source rock Occurrence Free fraction CM-bound fraction Bicyclic sesquiterpenoids Botryococcus braunii Biogenic significance
下载PDF
A branch-and-bound algorithm for discrete multi-factor portfolio optimization model 被引量:1
16
作者 牛淑芬 王国欣 孙小玲 《Journal of Shanghai University(English Edition)》 CAS 2008年第1期26-30,共5页
In this paper, a new branch-and-bound algorithm based on the Lagrangian dual relaxation and continuous relaxation is proposed for discrete multi-factor portfolio selection model with roundlot restriction in financial ... In this paper, a new branch-and-bound algorithm based on the Lagrangian dual relaxation and continuous relaxation is proposed for discrete multi-factor portfolio selection model with roundlot restriction in financial optimization. This discrete portfolio model is of integer quadratic programming problems. The separable structure of the model is investigated by using Lagrangian relaxation and dual search. Computational results show that the algorithm is capable of solving real-world portfolio problems with data from US stock market and randomly generated test problems with up to 120 securities. 展开更多
关键词 portfolio optimization discrete multi-factor model Lagrangian relaxation and continuous relaxation branch-and-bound method.
下载PDF
Antisymmetric quadrupole mode of coherent structures in wall-bounded turbulence 被引量:1
17
作者 Haiping Tian Shaoqiong Yang +2 位作者 Lu Cheng Yuan Wang Nan Jiang 《Theoretical & Applied Mechanics Letters》 CAS 2013年第5期58-61,共4页
Abstract Experiments were conducted in a water tunnel by tomographic time-resolved particle image velocimetry (Tomo-TRPIV). The Reynolds number Reo is 2 460 on the base of momentum thickness. According to the physic... Abstract Experiments were conducted in a water tunnel by tomographic time-resolved particle image velocimetry (Tomo-TRPIV). The Reynolds number Reo is 2 460 on the base of momentum thickness. According to the physical mechanism of the stretch and compression of multi-scale vortex structures in the wall-bounded turbulence, the topological characteristics of turbulence statistics in logarithmic layer were illustrated by local-averaged velocity structure function. During coherent structures bursting, results reveal that the topological structures of velocity gradients, velocity strain rates and vorticities behave as antisymmetric quadrupole modes. A three-layer antisymmetric quadrupole vortex packet confirms that there is a tight relationship between the outer layer and the near-wall layer. 展开更多
关键词 wall-bounded turbulence antisymmetric quadrupole mode Tomo-TRPIV vortex packet coherent structure
下载PDF
Using Double-Bounded Dichotomous-Choice to Estimate Households’ Willingness to Pay for Improved Water Quality in Bac Ninh Province of Vietnam 被引量:1
18
作者 Nguyen Van Song Vu Ngoc Huyen +1 位作者 Le Thi Phuong Dung Nguyen Thi Thuy 《Journal of Environmental Protection》 2019年第11期1407-1418,共12页
This study used double-bounded dichotomous-choice to estimate and analyze the factors affecting households’ willingness to pay (WTP) for water quality improvement. This study notes that households with higher income,... This study used double-bounded dichotomous-choice to estimate and analyze the factors affecting households’ willingness to pay (WTP) for water quality improvement. This study notes that households with higher income, living near a polluted water source, using tap water instead of natural water, who are handicraft producers, and who have more members, are willing to pay more. However, households who rarely hear about environmental pollution issues and who are offered a higher bid are more likely to refuse to pay. Solutions to improve water quality are suggested such as to raise people’s awareness through communication channels and social organizations;to increase income associated with environmental protection policies;to construct wastewater treatment plants;to encourage the relocation of production establishments to industrial parks and industrial complexes;to put regulations on collection, payment and sanctions in case of not declaring and paying fees into village conventions;to promulgate circulars, and bylaws to concretize and simplify regulations and policies of the Government and the Ministry of Natural Resources and Environment. 展开更多
关键词 Double-bounded Dichotomous-Choice WILLINGNESS to PAY Water Quality Improvement HANDICRAFT Households
下载PDF
Predefined Exponential Basis Set for Half-Bounded Multi Domain Spectral Method 被引量:1
19
作者 Fahhad Alharbi 《Applied Mathematics》 2010年第3期146-152,共7页
A non-orthogonal predefined exponential basis set is used to handle half-bounded domains in multi domain spectral method (MDSM). This approach works extremely well for real-valued semi-infinite differential problems. ... A non-orthogonal predefined exponential basis set is used to handle half-bounded domains in multi domain spectral method (MDSM). This approach works extremely well for real-valued semi-infinite differential problems. It spans simultaneously wide range of exponential decay rates with multi scaling and does not suffer from zero crossing. These two conditions are necessary for many physical problems. For comparison, the method is used to solve different problems and compared with analytical and published results. The comparison exhibits the strengths and accuracy of the presented basis set. 展开更多
关键词 Multi-Domain Spectral METHOD MESHFREE Numerical METHOD Non-Orthogonal Predefined EXPONENTIAL Basis Set Half-bounded Domain EXPONENTIAL Decay Quantum Wells Optical Waveguide
下载PDF
Ψ-bounded Solutions for a System of Difference Equations on Z
20
作者 HAN YU-LIANG LIu BAI-FENG SUN XI-DONG 《Communications in Mathematical Research》 CSCD 2011年第4期331-342,共12页
In this work we discuss the existence of ψ-bounded solutions for linear difference equations. We present a necessary and sufficient condition for the existence of ψ--bounded solutions for the linear nonhomogeneous d... In this work we discuss the existence of ψ-bounded solutions for linear difference equations. We present a necessary and sufficient condition for the existence of ψ--bounded solutions for the linear nonhomogeneous difference equation x(n+1)=A(n)x(n)+f(n) for every ψ-bounded sequence f(n). 展开更多
关键词 difference equation ψ-bounded solution EXISTENCE
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部