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Economic Growth Model Based on Six Basic Factors of Production—Xu Growth Rate Equation

Shou-bo Xu,Zong-yuan Huang

《工程管理前沿（英文）》 2014年 第1卷 第2期   页码 160-175 doi: 10.15302/J-FEM-2014024

摘要： This paper proposes an economic growth model based on the Six Basic Factors of Production and Xu Growth Rate Equation for the first time, which fills-in the deficits of the New Classical Economic Growth Model based on the Solow Model. The empirical analysis indicates that over the past three decades, the consumption of six basic factors of production had complicated relations with economic growth. In some years, the consumption rate of the basic factors of production was meager, but the economy witnessed relatively rocketing growth rate; in some years, the factors of production consumption rate was very high, but the economy growth rate slowed down. In general, economy grows at the expenses of huge consumption of four factors. There is an obvious characteristic of huge input and low efficiency. The average contribution rate of technological advance peaks in the middle, while it drops down at two ends. Noticeably, since 2004, the technology contribution rate generally shows a downward trend, reasons of which should be explored systematically in aspects like economic policy and industry structure with a view to boost further transformation of the macro-economy scientific growth model.

关键词： six basic factors of production     economic growth model     Xu Growth Rate Equation    

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A study of spray granulation in vibrated fluidized bed with internal heating tubes

Xiaoheng PAN, Shichao YE, Zeguang ZHANG, Li ZHANG, Xuejun ZHU

《化学科学与工程前沿（英文）》 2009年 第3卷 第1期   页码 78-82 doi: 10.1007/s11705-009-0084-x

摘要： The granulation process in a vibrated fluidized bed with immersed horizontal heating tubes was studied in this paper, with small monoammonium phosphate particles as the initial particles and monoammonium phosphate solution sprayed on them. The concrete influences on the granulating performance of the immersed horizontal heating power, fluidizing gas velocity, vibration frequency and amplitude had been analyzed theoretically. The results show that appropriate vibration intensity is a preferred condition for the growth of partials, but the fine dust will become much more along with prolonged vibration. Increasing the heating power is beneficial to raise the growth rate. Particles will grow faster if the fluidizing gas velocity is higher, but this will cause more fine dust. The optimized condition of =0.002 m, =6.67 Hz, =1.4 m/s was given after the analysis of the experimental results. In the end, a semiempirical formula was derived from the experiment data, and the calculation results show good agreement with the experimental data.

关键词： vibrated fluidized bed     immersed horizontal     horizontal heating tubes     spray granulation     particle growth model    

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Effect of adjusted mesoscale drag model on flue gas desulfurization in powder-particle spouted beds

《化学科学与工程前沿（英文）》 2022年 第16卷 第6期   页码 909-920 doi: 10.1007/s11705-021-2100-8

摘要： An energy minimum multiscale model was adjusted to simulate the mesoscale structure of the flue gas desulfurization process in a powder-particle spouted bed and verified experimentally. The obtained results revealed that the spout morphology simulated by the adjusted mesoscale drag model was unstable and discontinuous bubbling spout unlike the stable continuous spout obtained using the Gidaspow model. In addition, more thorough gas radial mixing was achieved using the adjusted mesoscale drag model. The mass fraction of water in the gas mixture at the outlet determined by the heterogeneous drag model was 1.5 times higher than that obtained by the homogeneous drag model during the simulation of water vaporization. For the desulfurization reaction, the experimental desulfurization efficiency was 75.03%, while the desulfurization efficiencies obtained by the Gidaspow and adjusted mesoscale drag models were 47.63% and 75.08%, respectively, indicating much higher accuracy of the latter technique.

关键词： adjusted mesoscale drag model     particle image velocimetry     water vaporization     desulfurization reaction     numerical simulation    

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Key features of new particle formation events at background sites in China and their influence on cloud

Xiaojing SHEN,Junying SUN,Xiaoye ZHANG,Yangmei ZHANG,Lu ZHANG,Ruxia FAN

《环境科学与工程前沿（英文）》 2016年 第10卷 第5期 doi: 10.1007/s11783-016-0833-2

摘要： New particle formation (NPF) event at multi rural sites in China Identifying the characteristics of NPF event Comparing NPF event between clean and polluted conditions Quantifying contribution to the cloud condensation nuclei Implication of climate and air quality Long-term continuous measurements of particle number size distributions with mobility diameter sizes ranging from 3 to 800 nm were performed to study new particle formation (NPF) events at Shangdianzi (SDZ), Mt. Tai (TS), and Lin’an (LAN) stations representing the background atmospheric conditions in the North China Plain (NCP), Central East China (CEC), and Yangtze River Delta (YRD) regions, respectively. The mean formation rate of 3-nm particles was 6.3, 3.7, and 5.8 cm ·s , and the mean particle growth rate was 3.6, 6.0, and 6.2 nm·h at SDZ, TS, and LAN, respectively. The NPF event characteristics at the three sites indicate that there may be a stronger source of low volatile vapors and higher condensational sink of pre-existing particles in the YRD region. The formation rate of NPF events at these sites, as well as the condensation sink, is approximately 10 times higher than some results reported at rural/urban sites in western countries. However, the growth rates appear to be 1–2 times higher. Approximately 12%–17% of all NPF events with nucleated particles grow to a climate-relevant size (>50 nm). These kinds of NPF events were normally observed with higher growth rate than the other NPF cases. Generally, the cloud condensation nuclei (CCN) number concentration can be enhanced by approximately a factor of 2–6 on these event days. The mean value of the enhancement factor is lowest at LAN (2–3) and highest at SDZ (~4). NPF events have also been found to have greater impact on CCN production in China at the regional scale than in the other background sites worldwide.

关键词： New particle formation     Regional background     Cloud condensation nuclei     Growth rate     Formation rate    

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A reliability growth model for 300?MW pumped-storage power units

Jinyuan SHI , Yu YANG , Zhicheng DENG ,

《能源前沿（英文）》 2009年 第3卷 第3期   页码 337-340 doi: 10.1007/s11708-009-0032-y

摘要： A reliability growth model for pumped-storage power units is presented. Ways for estimating and fitting on checking the model’s parameters are given together with analysis results concerning the reliability growth of 300MW pumped-storage power units. On site operation, reliability data show that the reliability growth model conforms to rules of reliability growth tendency. Analysis results of reliability growth indicate that measures taken for improving maintenance and operation by the pumped-storage power companies are effective and that the reliability of the 300MW pumped-storage power units exhibits a rising tendency.

关键词： pump-storage power unit     availability     reliability growth     reliability prediction    

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Microdamage study of granite under thermomechanical coupling based on the particle flow code

《结构与土木工程前沿（英文）》   页码 1413-1427 doi: 10.1007/s11709-023-0953-2

摘要： The thermomechanical coupling of rocks refers to the interaction between the mechanical and thermodynamic behaviors of rocks induced by temperature changes. The study of this coupling interaction is essential for understanding the mechanical and thermodynamic properties of the surrounding rocks in underground engineering. In this study, an improved temperature-dependent linear parallel bond model is introduced under the framework of a particle flow simulation. A series of numerical thermomechanical coupling tests are then conducted to calibrate the micro-parameters of the proposed model by considering the mechanical behavior of the rock under different thermomechanical loadings. Good agreement between the numerical results and experimental data are obtained, particularly in terms of the compression, tension, and elastic responses of granite. With this improved model, the thermodynamic response and underlying cracking behavior of a deep-buried tunnel under different thermal loading conditions are investigated and discussed in detail.

关键词： thermomechanical coupling effect     granite     improved linear parallel bond model     thermal property     particle flow code    

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Availability growth models and verification of power equipment

Jinyuan SHI, Jiamin XU

《能源前沿（英文）》 2021年 第15卷 第2期   页码 529-538 doi: 10.1007/s11708-019-0624-0

摘要： The general availability growth models for large scale complicated repairable system such as electric generating units, power station auxiliaries, and transmission and distribution installations are presented. The calculation formulas for the maintenance coefficient, mathematical expressions for general availability growth models, ways for estimating, and fitting on checking the parameters of the model are introduced. Availability growth models for electric generating units, power station auxiliaries, and transmission and distribution installations are given together with verification examples for availability growth models of 320–1000 MW nuclear power units and 1000 MW thermal power units, 200–1000 MW power station auxiliaries, and 220–500 kV transmission and distribution installations. The verification results for operation availability data show that the maintenance coefficients for electric generating units, power station auxiliaries, transmission and distribution installations conform to the power function, and general availability growth models conform to rules of availability growth tendency of power equipment.

关键词： repairable system     power equipment     electric generating unit     power station auxiliary     transmission and distribution installation     reliability     availability     availability growth model    

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Particle swarm optimization model to predict scour depth around a bridge pier

Shahaboddin SHAMSHIRBAND, Amir MOSAVI, Timon RABCZUK

《结构与土木工程前沿（英文）》 2020年 第14卷 第4期   页码 855-866 doi: 10.1007/s11709-020-0619-2

摘要： Scour depth around bridge piers plays a vital role in the safety and stability of the bridges. The former approaches used in the prediction of scour depth are based on regression models or black box models in which the first one lacks enough accuracy while the later one does not provide a clear mathematical expression to easily employ it for other situations or cases. Therefore, this paper aims to develop new equations using particle swarm optimization as a metaheuristic approach to predict scour depth around bridge piers. To improve the efficiency of the proposed model, individual equations are derived for laboratory and field data. Moreover, sensitivity analysis is conducted to achieve the most effective parameters in the estimation of scour depth for both experimental and filed data sets. Comparing the results of the proposed model with those of existing regression-based equations reveal the superiority of the proposed method in terms of accuracy and uncertainty. Moreover, the ratio of pier width to flow depth and ratio of 50 (mean particle diameter) to flow depth for the laboratory and field data were recognized as the most effective parameters, respectively. The derived equations can be used as a suitable proxy to estimate scour depth in both experimental and prototype scales.

关键词： scour depth     bridge design and construction     particle swarm optimization     computational mechanics     artificial intelligence     bridge pier    

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Concurrent fatigue crack growth simulation using extended finite element method

Zizi LU, Yongming LIU,

《结构与土木工程前沿（英文）》 2010年 第4卷 第3期   页码 339-347 doi: 10.1007/s11709-010-0078-2

摘要： In this paper, a concurrent simulation framework for fatigue crack growth analysis is proposed using a novel small time scale model for fatigue mechanism analysis and the extended finite element method (X-FEM) for fatigue crack growth simulation. The proposed small time scale fatigue model does not require the cycle counting as those using the classical fatigue analysis methods and can be performed concurrently with structural/mechanical analysis. The X-FEM greatly facilitates crack growth simulation without remeshing requirements ahead of the crack tip as in the classical finite element method. The basic concept and theory of X-FEM was briefly introduced and numerical predictions of stress intensity factors are verified with reference solutions under both uniaxial and multiaxial loadings. The small time scale fatigue model is integrated into the numerical simulation algorithm for concurrent fatigue crack growth analysis. Model predictions are compared with available experimental observations for model validation.

关键词： small time scale model     extended finite element method (X-FEM)     crack growth     multiaxial    

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Bacteria-mediated tumor-targeted delivery of tumstatin (54-132) significantly suppresses tumor growthin mouse model by inhibiting angiogenesis and promoting apoptosis

《医学前沿（英文）》 2022年 第16卷 第6期   页码 873-882 doi: 10.1007/s11684-022-0925-2

摘要： Tumor growth is an angiogenesis-dependent process and accompanied by the formation of hypoxic areas. Tumstatin is a tumor-specific angiogenesis inhibitor that suppresses the proliferation and induces the apoptosis of tumorous vascular endothelial cells. VNP20009, an attenuated Salmonella typhimurium strain, preferentially accumulates in the hypoxic areas of solid tumors. In this study, a novel Salmonella-mediated targeted expression system of tumstatin (VNP-Tum5) was developed under the control of the hypoxia-induced J23100 promoter to obtain anti-tumor efficacy in mice. Treatment with VNP-Tum5 effectively suppressed tumor growth and prolonged survival in the mouse model of B16F10 melanoma. VNP-Tum5 exhibited a higher efficacy in inhibiting the proliferation and inducing the necrosis and apoptosis of B16F10 cells in vitro and in vivo compared with VNP (control). VNP-Tum5 significantly inhibited the proliferation and migration of mouse umbilical vascular endothelial cells to impede angiogenesis. VNP-Tum5 downregulated the expression of anti-vascular endothelial growth factor A, platelet endothelial cell adhesion molecule-1, phosphorylated phosphoinositide 3 kinase, and phosphorylated protein kinase B and upregulated the expression of cleaved-caspase 3 in tumor tissues. This study is the first to use tumstatin-transformed VNP20009 as a tumor-targeted system for treatment of melanoma by combining anti-tumor and anti-angiogenic effects.

关键词： Salmonella VNP20009     tumstatin     B16F10     melanoma     apoptosis     angiogenesis    

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Application of a weakly compressible smoothed particle hydrodynamics multi-phase model to non-cohesive

Rasoul MEMARZADEH, Gholamabbas BARANI, Mahnaz GHAEINI-HESSAROEYEH

《结构与土木工程前沿（英文）》 2018年 第12卷 第3期   页码 412-424 doi: 10.1007/s11709-017-0432-8

摘要：

The subject of present study is the application of mesh free Lagrangian two-dimensional non-cohesive sediment transport model applied to a two-phase flow over an initially trapezoidal-shaped sediment embankment. The governing equations of the present model are the Navier-Stocks equations solved using Weakly Compressible Smoothed Particle Hydrodynamics (WCSPH) method. To simulate the movement of sediment particles, the model considers a powerful two-part technique; when the sediment phase has rigid behavior, only the force term due to shear stress in the Navier-Stokes equations is used for simulation of sediment particles’ movement. Otherwise, all the Navier-Stokes force terms are used for transport simulation of sediment particles. In the present model, the interactions between different phases are calculated automatically, even with considerable difference between the density and viscosity of phases. Validation of the model is performed using simulation of available laboratory experiments, and the comparison between computational results and experimental data shows that the model generally predicts well the flow propagation over movable beds, the induced sediment transport and bed changes, and temporal evolution of embankment breaching.

关键词： WCSPH method     non-cohesive sediment transport     rheological model     two-part technique     two-phase dam break    

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Effect of atorvastatin on tumor growth and metastasis in a breast cancer cell xenograft model and its

Liu LIU MD, PhD, Yaogui NING MM, Chen CHEN MD, Daowen WANG MD, PhD,

《医学前沿（英文）》 2009年 第3卷 第4期   页码 443-446 doi: 10.1007/s11684-009-0079-5

摘要： This paper aims to evaluate the effects and the possible mechanisms of atorvastatin on tumor growth and metastasis in a xenograft tumor model. Twenty-four female athymic BALB/C mice with MDA-MB-435 xenograft tumors were randomly assigned to three groups: a control group, a low-dose atorvastatin treatment group, and a high-dose atorvastatin treatment group. The mice in the treatment groups began to be administered with atorvastatin (10 or 20 mg/kg per day) when the xenograft tumors reached 1 cm in diameter. At the end of the experiment, the tumor volume and weight and the lung metastasis colonies of each mouse were measured. Western blotting was applied to detect phosphorylation of protein kinase B (PKB, Akt), extracellular signal regulated kinase (ERK), c-Jun N-terminal Kinase (JNK), and the expression of cytochrome P450 (CYP) subtype CYP2J2. Atorvastatin suppressed xenograft tumor growth and metastasis both in the low-dose and the high-dose treatment groups ( < 0.05). Atorvastatin also decreased the phosphorylated Akt (p-Akt) and p-ERK but increased p-JNK expression. However, atorvastatin did not alter the expression of CYP2J2 in tumor tissue. This suggests that atorvastatin has the efficacy of suppressing tumor growth and metastasis . These effects were not dependent on down-regulation of CYP2J2 expression.

关键词： atorvastatin     xenograft tumor     metastasis     CYP2J2    

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Influence of welding residual stresses on the ductile crack growth resistance of circumferentially cracked

Xiaobo REN, Odd M. AKSELSEN, B?rd NYHUS, Zhiliang ZHANG

《结构与土木工程前沿（英文）》 2012年 第6卷 第3期   页码 217-223 doi: 10.1007/s11709-012-0169-3

摘要： Welding residual stress is one of the main concerns for fabrication and operation of steel structures due to its potential effect on structural integrity. This paper focuses on the effect of welding residual stress on the ductile crack growth resistance of circumferentially cracked steel pipes. Two-dimensional axi-symmetry model has been used to simulate the pipe. Residual stresses were introduced into the model by using so-called eigenstrain method. The complete Gurson model has been employed to calculate the ductile crack growth resistance. Results show that residual stresses reduce the ductile crack growth resistance. However, the effect of residual stresses on ductile crack growth resistance decreases with the increase of crack growth. The effect of residual stress has also been investigated for cases with different initial void volume fraction, material hardening and crack sizes.

关键词： residual stress     ductile crack growth resistance     complete Gurson model     eigenstrain method    

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大空间内着火位置对火灾增长的影响

石龙,张瑞芳, 谢启源,付丽华

《中国工程科学》 2008年 第10卷 第11期   页码 37-42

摘要：

以大空间展厅为例，利用火源辐射模型和烟气辐射模型并结合CFAST6.0区域模拟软件的计算结果，对比分析了大空间内不同着火位置下火灾增长的情况。研究结果表明仅考虑火源热辐射的情况下，展厅内着火位置越处于左右中间对称处，其火灾增长越快，热释放速率峰值也越大，达到热释放速率峰值的时间和火灾的持续时间越短，处于展厅中心位置时所有值达峰值。对火源热辐射和烟气辐射综合考虑时，到达热释放速率峰值时间与火灾持续时间的规律同仅考虑火源辐射模型时一致，但热释放速率峰值均有不同程度的提高。

关键词： 火灾增长     大空间着火位置     火灾场景设置     火源辐射模型     烟气辐射模型    

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Simulation of cohesive crack growth by a variable-node XFEM

Weihua FANG, Jiangfei WU, Tiantang YU, Thanh-Tung NGUYEN, Tinh Quoc BUI

《结构与土木工程前沿（英文）》 2020年 第14卷 第1期   页码 215-228 doi: 10.1007/s11709-019-0595-6

摘要： A new computational approach that combines the extended finite element method associated with variable-node elements and cohesive zone model is developed. By using a new enriched technique based on sign function, the proposed model using 4-node quadrilateral elements can eliminate the blending element problem. It also allows modeling the equal stresses at both sides of the crack in the crack-tip as assumed in the cohesive model, and is able to simulate the arbitrary crack-tip location. The multiscale mesh technique associated with variable-node elements and the arc-length method further improve the efficiency of the developed approach. The performance and accuracy of the present approach are illustrated through numerical experiments considering both mode-I and mixed-mode fracture in concrete.

关键词： extended finite element method     cohesive zone model     sign function     crack propagation    

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标题 作者 时间 类型 操作

Economic Growth Model Based on Six Basic Factors of Production—Xu Growth Rate Equation

Shou-bo Xu,Zong-yuan Huang

期刊论文

A study of spray granulation in vibrated fluidized bed with internal heating tubes

Xiaoheng PAN, Shichao YE, Zeguang ZHANG, Li ZHANG, Xuejun ZHU

期刊论文

Effect of adjusted mesoscale drag model on flue gas desulfurization in powder-particle spouted beds

期刊论文

Key features of new particle formation events at background sites in China and their influence on cloud

Xiaojing SHEN,Junying SUN,Xiaoye ZHANG,Yangmei ZHANG,Lu ZHANG,Ruxia FAN

期刊论文

A reliability growth model for 300?MW pumped-storage power units

Jinyuan SHI , Yu YANG , Zhicheng DENG ,

期刊论文

Microdamage study of granite under thermomechanical coupling based on the particle flow code

期刊论文

Availability growth models and verification of power equipment

Jinyuan SHI, Jiamin XU

期刊论文

Particle swarm optimization model to predict scour depth around a bridge pier

Shahaboddin SHAMSHIRBAND, Amir MOSAVI, Timon RABCZUK

期刊论文

Concurrent fatigue crack growth simulation using extended finite element method

Zizi LU, Yongming LIU,

期刊论文

Bacteria-mediated tumor-targeted delivery of tumstatin (54-132) significantly suppresses tumor growthin mouse model by inhibiting angiogenesis and promoting apoptosis

期刊论文

Application of a weakly compressible smoothed particle hydrodynamics multi-phase model to non-cohesive

Rasoul MEMARZADEH, Gholamabbas BARANI, Mahnaz GHAEINI-HESSAROEYEH

期刊论文

Effect of atorvastatin on tumor growth and metastasis in a breast cancer cell xenograft model and its

Liu LIU MD, PhD, Yaogui NING MM, Chen CHEN MD, Daowen WANG MD, PhD,

期刊论文

Influence of welding residual stresses on the ductile crack growth resistance of circumferentially cracked

Xiaobo REN, Odd M. AKSELSEN, B?rd NYHUS, Zhiliang ZHANG

期刊论文

大空间内着火位置对火灾增长的影响

石龙,张瑞芳, 谢启源,付丽华

期刊论文

Simulation of cohesive crack growth by a variable-node XFEM

Weihua FANG, Jiangfei WU, Tiantang YU, Thanh-Tung NGUYEN, Tinh Quoc BUI

期刊论文