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Estimating Users’ Intentions and Behaviours of Electronic Bidding System

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Estimating Users’ Intentions and Behaviours of Electronic B...

Effects of Adiabatic Dust Charge Fluctuation and Particles Collisions on Dust-Acoustic Solitary Waves in Three-Dimensional Magnetized Dusty Plasmas

第25届中国控制与决策会议

作者： jian chen Ziping Chiang Department of Logistics and Technique Management University of Kang Ning

ISBN: (纸本)9781467355339

Electronic Bidding System （EBS） is one of the most important operational solutions of public administration, as well as the establishment of the conditions necessary for taking advantage of electronic administration. But few papers discussed the users’ aesthesis in using Electronic Bidding System for the feedback control. Thus the main purpose of this paper is to investigate the current status and the factors of the users’ intentions and behaviors in using Electronic Bidding System. The judgment framework is Structural Equation Modeling （SEM） based on the Unified Theory of Acceptance and Use of Technology Model （UTAUT） to research the influence of the four factors, Performance Expectancy, Effort Expectancy, Social Influence, and Facilitating Conditions on the intentions and behaviors. A questionnaire survey is conducted to collect 192 valid samples for quantitative analysis. The sample number in Tainan Taiwan is 102 and the others are from Nanping Fujian. The results are shown as following. （1）. Performance Expectancy and Social Influence have a significantly impact on the users’ intentions and behaviors in using Electronic Bidding System, but not in Effort Expectancy. （2）. Facilitating Conditions have a significantly impact on the users’ behaviors in using Electronic Bidding System, but in use Intention. （3）. The difference between samples from Tainan Taiwan mad Nanping Fujian are significant in 5 of 9 factors.

关键词： Electronic Bidding System, Users’ Aesthesis Structural Equation Modeling, Unified Theory of Acceptance and Use of Technology Model, Feedback Control

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Communications in Theoretical Physics 2009年第3期51卷 524-528页

作者： chen jian-Hong WEI Nan-Xia Department of Physics Lanzhou City University Lanzhou 730070 China Provincial Center for School Curricuhum and Textbook Education Department of Gansu Prinvince Lanzhou 730000 China

Taking into account the combined effects of the external magnetic field, adiabatic dust charge fluctuation and collisions occurring between the charged dust grains and neutral gas particles （dust-neutral collisions）, the dust-acoustic solitary waves in three-dimensional uniform dusty plasmas are investigated analytically. By using the reductive perturbation method, the Korteweg-de Vries （KdV） equation governing the dnst-aconstic solitary waves is obtained. The present analytical results show that only rarefactive solitary waves exist in this system. It is also found that the effects of the wave vector along the z-direction, dust charge variation, collisional frequency, the plasma density, and temperature ratio can significantly influence the characteristics of low-frequency wave modes. Moreover, for the collisional dusty plasmas, there is a certain critical value μc of the plasma density ratio μ, if μ 〈 μc, the width of the waves increases with μ, otherwise the width of waves decreases with μ.

关键词： adiabatic variation KdV equation solitary waves

Controlled Synthesis of Core-Shell Nickel Microspheres with Solid Core and Porous Shell by Precipitation and Thermal Decomposition Method

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Journal of Wuhan University of Technology(Materials Science) 2019年第4期34卷 824-829页

作者： LI Tao MA Guohua chen jian GONG Yong School of Mechanical Engineering Chengdu UniversityChengdu 610106China College of Materials Science and Engineering Southwest University of Science and TechnologyMianyang 621010China Analysis and Testing Center Southwest University of Science and TechnologyMianyang 621010China Sichuan University of Science & Engineering Material Corrosion and Protection Key Laboratory of Sichuan ProvinceZigong 643000China

Nickel oxalate micro-spheres with core-shell structure of solid core and radiate shell were synthesized by precipitation method in a mixed water solution, with oxalic acid and nickel acetate as raw materials, through dropping ammonium hydroxide to adjust the solution pH value to about 8.0. Nickel microspheres with core-shell structure of solid core and porous shell were prepared by decomposing of nickel oxalate microspheres precursor at about 340 ℃ in argon atmosphere. The analyses of infrared spectroscopy(IR)indicates that the composition of the powders is nickel oxalate. The analyses of atomic absorption spectrometry(AAS) and organic elemental analysis(OEA) indicate that the molar ratio of(C2O4)^2-/Ni^2+ is about 1.02, close to the theoretical value of 1.0. The results of the thermo-gravimetric and differential thermal gravity analyses(TG-DTG) indicate that the molar ratio of(C2O4)^2-/Ni^2+ is about 1.06, also close to the theoretical value of *** analysis of X-ray diffraction(XRD) indicates that the composition of black powders as-prepared is nickel,which has a face-centered cubic crystal structure with average crystal grain size about 16.87 nm. The images of scanning electron microscopy(SEM) indicate that the morphology of nickel oxalate microspheres is a coreshell structure with solid core and radiate shell. The diameter of nickel oxalate microspheres is about 3 μm, and the shell consists of a large number of thin nanorods. The images of SEM also indicate that the morphology of nickel microspheres is a core-shell structure with solid core and porous shell. The diameter of nickel microspheres is about 2 μm, and the shell consists of a large number of nickel grains, surface holes and through holes. The diameter of nickel grains is about 50-100 nm, and the diameter of holes is about 50-200 nm.

关键词： nickel oxalate nickel core-shell porous precipitation thermal-decomposition

Response of Solenopsis invicta （Hymenoptera： Formicidae） to potassium oleate water solution

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Insect Science 2010年第2期17卷 121-128页

作者： jian chen Han-Wu Shang Xixuan Jin Biological Control of Pests Research Unit Agricultural Research Service U.S. Department of Agriculture Stoneville Mississippi USA College of Life Sciences China Jiliang University Hangzhou China

In contrast to floating on the surface of distilled water, ants were immediately submerged after being placed in the potassium oleate （PO） water solution, which led to immobilization within minutes. However, some workers survived after being immersed in 0.03% PO water solution at 25℃ for up to 640 rnin. Elevated temperature of the PO water solution is needed to kill ants within a shorter time frame. At 50℃ and 0.13% PO concentration, total mortality was achieved with 10-min immersion for all ants, including brood and adult ants. Soil has a negative effect on the effectiveness of potassium oleate; however, such negative effect can be overcome by increasing either treatment temperature or duration of the treatment. In addition to immobilizing and lethal effect, PO repels ants. PO may have the potential to be incorporated into immersion treatment for the quarantine of imported fire ants to reduce the use of synthetic contact insecticides.

关键词： dipping immersion treatment quarantine soap surfactant

Effect of Hydrogen on Corrosion and Stress Corrosion Cracking of AZ91 Alloy in Aqueous Solutions

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Acta Metallurgica Sinica(English Letters) 2016年第1期29卷 1-7页

作者： jian chen jian-Qiu Wang En-Hou Han Wei Ke D.W.Shoesmith Department of Chemistry Western University Surface Science Western Western University Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of Sciences

The effect of hydrogen on the corrosion and stress corrosion cracking of the magnesium AZ91 alloy has been investigated in aqueous solutions. Hydrogen produced by corrosion in water diffuses into, and reacts with the Mg matrix to form hydride. Some of the hydrogen accumulates at hydride/Mg matrix （or secondary phase） interfaces as a consequence of slow hydride formation and the incompatibility of the hydride with the Mg matrix （or secondary phase）, and combines to form molecular hydrogen. This leads to the development of a local pressure at the hydride/Mg matrix （or secondary phase） interface. The expansion stress caused by hydride formation and the local hydrogen pressure due to its accumulation result in brittle fracture of hydride. These two combined effects promote both the corrosion rate of the AZ91 alloy, and crack initiation and propagation even in the absence of an external load. Hydrogen absorption leads to a dramatic deterioration in the mechanical properties of the AZ91 alloy, indicating that hydrogen embrittlement is responsible for transgulanar stress corrosion cracking in aqueous solutions.

关键词： AZ91 alloy Corrosion Hydrogen Secondary ion mass spectroscopy (SIMS) Transgulanarstress corrosion cracking (TGSCC)

Research on High Speed Communication Method of ELF-EM While Drilling Based on Adaptive Combined Filtering Algorithm

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China Communications 2023年第6期20卷 129-147页

作者： Fukai Li jian chen jianWu Huaiyun Peng Zhiqiang Yang School of Telecommunications Engineering Xidian UniversityXi’an 710071China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China

In terms of the electromagnetic wave measurement while drilling,the extremely low frequency electromagnetic(ELF-EM)signal below 20Hz is usually chosen as the downhole data *** improve the transmission rate of ELF-EM signal and the signal to noise ratio(SNR)at the receiving end,the DQPSK modulation was proposed as the modulation method for the communication of electromagnetic wave *** from the traditional IQ orthogonal modulation and coherent demodulation methods,the proposed phase selection modulation and correlation algorithm demodulation are easier to implement and more *** regard to the communication synchronization,a fast algorithm,which based on the normalized cross-relation number,was used for waveform matching,and the maximum point of the correlation coefficient was used as the starting point of communication *** communication simulation results show that the proposed DQPSK modulation signal based on the adaptive combined filtering algorithm has better terminal error rate and transmission rate than the traditional modulation *** the same carrier frequency and code width,the transmission rate of DQPSK modulation is 4 to 5 times and 2 times that of PPM modulation and 2DPSK modulation *** communication modulation and demodulation modes as well as the decoding algorithm with combined adaptive filter proposed in this paper can effectively solve practical engineering problems.

关键词： ELF-EM DQPSK normalized crosscorrelation adaptive combined filtering transmission rate

Theoretical and experimental investigation of holographic reconstruction and prediction of multi-source hybrid acoustic field

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Science China(Physics,Mechanics & Astronomy) 2005年第3期48卷 282-299页

作者： BI Chuanxing chen jian chen Xinzhao YU Fei LI Weibing Dynamic Measuring Center Hefei University of Technology Hefei 230009 China Dynamic Measuring Center Hefei University of Technology Hefei 230009 China Dynamic Measuring Center Hefei University of Technology Hefei 230009 China Dynamic Measuring Center Hefei University of Technology Hefei 230009 China Dynamic Measuring Center Hefei University of Technology Hefei 230009 China

Study on a multi-source hybrid acoustic field is very important for nearfield acoustic holography (NAH) to be applied in the practical engineering field. In this paper, two methods based on the distributed source boundary point method (DSBPM) for holographic reconstruction and prediction of multi-source hybrid acoustic field, namely combination method with single surface measurement and combination method with multi-surface measurement, are proposed. Then, an experiment on two coherent speakers is carried out. By comparison of the reconstructed and predicted results and the actual measured results, the validity of the two methods and the superiority of the combination method with multi-surface measurement are proved. Considering the high sensitivity of the reconstructed results to measurement errors, the Tikhonov regularization method is proposed to stabilize the reconstruction procedure and restrict the influence of errors. And then, the optimal reconstructed results can be obtained and the reliability of holographic reconstruction and prediction is assured.

关键词： acoustic holography, boundary point, distributed source, acoustic radiation, regularization.

Characteristics of viscous debris flow in a drainage channel with an energy dissipation structure

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Journal of Mountain Science 2016年第2期13卷 223-233页

作者： chen jian-gang chen Xiao-qing chen Hua-yong ZHAO Wan-yu CAS Key Laboratory of Mountain Hazards and Earth Surface Processes Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China CAS Center for Excellence in Tibetan Plateau Earth Sciences

A new type of drainage channel with an energy dissipation structure has been proposed based on previous engineering experiences and practical requirements for hazard mitigation in earthquakeaffected *** studies were performed to determine the characteristics of viscous debris flow in a drainage channel of this type with a slope of 15%.The velocity and depth of the viscous debris flow were measured,processed,and subsequently used to characterize the viscous debris flow in the drainage *** of this experiment showed that the surface of the viscous debris flow in a smooth drainage channel was smoother than that of a similar debris flow passing through the energy dissipation section in a channel of the new type studied ***,the flow patterns in the two types of channels were similar at other *** experimental results show that the depth of the viscous debris flow downstream of the energy dissipation structure increased gradually with the length of the energy dissipation *** addition,in the smooth channel,the viscous debris-flow velocity downstream of the energy dissipation structure decreased gradually with the length of the energy dissipation ***,theviscous debris-flow depth and velocity were slightly affected by variations in the width of the energy dissipation structure when the channel slope was 15%.Finally,the energy dissipation ratio increased gradually as the length and width of the energy dissipation structure increased;the maximum energy dissipation ratio observed was 62.9%(where B = 0.6m and L/w = 6.0).

关键词： Debris flow Drainage channel Energy dissipation structure Geological disaster

Separation theory of the incident and scattered sound fields in spherical coordinate

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Science China(Technological Sciences) 2007年第3期50卷 361-370页

作者： LI WeiBing LIAN MeiZhuan BI ChuanXing chen jian chen XinZhao Institute of Sound and Vibration Research Hefei University of TechnologyHefei 230009China Anhui jianghuai Automobile Co.Ltd Hefei 230022China

By the spherical wave spectrum transform,the sound pressures on the two spherical surfaces surrounding the scattering objects with arbitrarily-shaped sur-faces are decomposed into spherical wave components that propagate in a known manner,the relationships between the spherical wave components of the same order on the two spherical surfaces are established by the wave field extrapolation theorem,and the formula of the separation theory in the spherical coordinate is established in the wave-number domain. After separating the scattered pressure,the total scattered field can be obtained by holographic reconstruction and predic-tion. In order to overcome the instability of acoustic inverse problem,a new wave-number domain filter technique is proposed. It is proved that,as long as the two holographic spherical surfaces are taken to be close enough,the singularity of the separation formula can be avoided. The results of numerical simulation dem-onstrate the feasibility and validity of the separation theory.

关键词： spherical coordinate sound field separation spherical wave spectrum transform wave-number domain filter