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A novel model-free approach for reconstruction of time-delayed gene regulatory networks

中国科学：生命科学英文版 2006年第2期49卷 190-200页

作者： JIANG Wei1,2. LI Xia1,2.3,4, GUO Zheng1,2.3, LI Chuanxing1, WANG Lihong1 & RAO Shaoqi1,5 1. department of Bioinformatics, harbin Medical University, harbin 150086, china 2. department of Computer Science, harbin institute of technology, harbin 150080, china 3. School of Life Science and technology, Tongji University, Shanghai 2.0092. china 4. Biomedical engineering institute, Capital University of Medical Sciences, Beijing 100054, china 5. departments of Cardiovascular Medicine and Molecular Cardiology, Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA department of Bioinformatics Harbin Medical University Harbin 150086 China department of Computer Science Harbin Institute of Technology Harbin 150080 China School of Life Science technology Tongji University Shanghai 200092 China Biomedical engineering institute Capital University of Medical Sciences Beijing 100054 China departments of Cardiovascular Medicine Molecular Cardiology Cleveland Clinic Foundation Cleveland Ohio 44195 USA

Reconstruction of genetic networks is one of the key scientific challenges in functional genomics. This paper describes a novel approach for addressing the regulatory dependencies be-tween genes whose activities can be delayed by multiple units of time. The aim of the proposed ap-proach termed TdGRN (time-delayed gene regulatory networking) is to reversely engineer the dy-namic mechanisms of gene regulations, which is realized by identifying the time-delayed gene regu-lations through supervised decision-tree analysis of the newly designed time-delayed gene expres-sion matrix, derived from the original time-series microarray data. A permutation technique is used to determine the statistical classification threshold of a tree, from which a gene regulatory rule(s) is ex-tracted. The proposed TdGRN is a model-free approach that attempts to learn the underlying regula-tory rules without relying on any model assumptions. Compared with model-based approaches, it has several significant advantages: it requires neither any arbitrary threshold for discretization of gene transcriptional values nor the definition of the number of regulators (k). We have applied this novel method to the publicly available data for budding yeast cell cycling. The numerical results demonstrate that most of the identified time-delayed gene regulations have current biological knowledge supports.

关键词： gene regulatory networks, time delayed, decision tree.

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Synthesis and physicochemical properties of LiLa_(0.01)Mn_(1.99)O_(3.99)F_(0.01) cathode materials for lithium ion batteries

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Rare Metals 2008年第5期27卷 496-501页

作者： YI Tingfenga ZHOU Anna ZHU Yanrong ZHU Rongsun HU Xinguo School of Chemistry and Chemical engineering A nhui University of Technology Ma＇anshan 243002 China department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China

Spinel lithium manganese oxide cathode materials were synthesized using the ultrasonic-assisted sol-gel method. The synthesized samples were investigated by differential thermal analysis （DTA） and thermogravimetry （TG）, powder X-ray diffraction （XRD）, scanning electron microscopy （SEM）, cyclic voltammetry （CV）, and the charge-discharge test. TG-DTA shows that significant mass loss occurs in two temperature regions during the synthesis of LiLa0.01Mn1.9903.99F0.01. XRD data indicate that all samples exhibit the same pure spinel phase, and LiLa0.01Mn1.9903.99F0.01 and LiLa0.01Mn1.9904 samples have a better crystallinity than LiMn2.4. SEM images indicate that LiLa0.01Mn1.9903.99F0.01 has a slightly smaller particle size and a more regular morphology structure with narrow size distribution. The charge-discharge test reveals that the initial capacities of LiMn2.4, LiLa0.01Mn1.99O4, and LiLa0.01Mn1.99O3.99F0.01 are 130, 12., and 12. mAh·g^-1, respectively, and the capacity retention rates of the initial value, after 50 cycles, are 84.8%, 92.3%, and 92.1%, respectively. The electrode coulomb efficiency and CV reveal that the electrode synthesized by the ultrasonic-assisted sol-gel （UASG） method has a better re- versibility than the electrode synthesized by the sol-gel method.

关键词： lithium ion batteries cathode material lithium manganese oxide synthesis physicochemical properties

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A land surface model incorporated with soil freeze/thaw and its application in GAME/Tibet

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Science china Earth Sciences 2006年第12期49卷 1311-1322页

作者： HU Heping1, YE Baisheng2. ZHOU Yuhua3 & TIAN Fuqiang1 1. department of Hydraulic engineering, Tsinghua University, Beijing 100084,{2. 2. Cold and Arid Regions environmental and engineering Research institute, Chinese Academy of Sciences, Lanzhou 730000,{2. 3. department of Civil engineering, Massachusetts institute of technology, USA 1. department of Hydraulic engineering Tsinghua University Beijing 100084 China 2. Cold and Arid Regions environmental and engineering Research {2. Chinese Academy of Sciences Lanzhou 730000 China 3. department of Civil engineering Massachusetts Institute of Technology USA

Land surface process is of great importance in global climate change, moisture and heat exchange in the interface of the earth and atmosphere, human impacts on the environment and eco- system, etc. Soil freeze/thaw plays an important role in cold land surface processes. In this work the diurnal freeze/thaw effects on energy partition in the context of GAME/Tibet are studied. A sophisti- cated land surface model is developed, the particular aspect of which is its physical consideration of soil freeze/thaw and vapor flux. The simultaneous water and heat transfer soil sub-model not only reflects the water flow from unfrozen zone to frozen fringe in freezing/thawing soil, but also demon- strates the change of moisture and temperature field induced by vapor flux from high temperature zone to low temperature zone, which makes the model applicable for various circumstances. The modified Picard numerical method is employed to help with the water balance and convergence of the numerical scheme. Finally, the model is applied to analyze the diurnal energy and water cycle char- acteristics over the Tibetan Plateau using the Game/Tibet datasets observed in May and July of 1998. Heat and energy transfer simulation shows that: (i) There exists a negative feedback mechanism between soil freeze/thaw and soil temperature/ground heat flux; (ii) during freezing period all three heat fluxes do not vary apparently, in spite of the fact that the negative soil temperature is higher than that not considering soil freeze; (iii) during thawing period, ground heat flux increases, and sensible heat flux decreases, but latent heat flux does not change much; and (iv) during freezing period, soil temperature decreases, though ground heat flux increases.

关键词： land surface model,soil freeze/thaw,GAME/Tibet,simultaneous liquid,vapor and heat transfer.

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Biological exposure models for oil spill impact analysis

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Journal of environmental Sciences 2000年第4期12卷 482-485页

作者： XIONG De qi 1, Mark Reed 2. Narve Ekrol 2.(1. department of Marine environmental {2., Dalian Maritime University, Dalian 11602., china E mail: deqi@*** 2. department of environmental engineering, SINTEF Applied Chemistry Institut 大连海事大学辽宁大连 1 1 6 0 2 SINTEF Applied Chemistry institute 挪威 Trondheim 70 3 4

The oil spill impact analysis (OSIA) software system has been developed to supply a tool for comprehensive, quantitative environmental impact assessments resulting from oil spills. In the system, a biological component evaluates potential effects on exposed organisms based on results from a physico chemical fates component, including the extent and characteristics of the surface slick, and dissolved and total concentrations of hydrocarbons in the water column. The component includes a particle based exposure model for migratory adult fish populations, a particle based exposure model for spawning planktonic organisms (eggs and larvae), and an exposure model for wildlife species (sea birds or marine mammals). The exposure model for migratory adult fish populations simulates the migration behaviors of fish populations migrating to or staying in their feeding areas, over wintering areas or spawning areas, and determines the acute effects (mortality) and chronic accumulation (body burdens) from the dissolved contaminant. The exposure model for spawning planktonic organisms simulates the release of eggs and larvae, also as particles, from specific spawning areas during the spawning period, and determines their potential exposure to contaminants in the water or sediment. The exposure model for wild species calculates the exposure to surface oil of wildlife (bird and marine mammal) categories inhabiting the contaminated area. Compared with the earlier models in which all kinds of organisms are assumed evenly and randomly distributed, the updated biological exposure models can more realistically estimate potential effects on marine ecological system from oil spill pollution events.

关键词： oil spill biological exposure acute effects chronic accumulation migration of fish spawning of eggs and larvae habitat

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On Minimum Norm Control for an Elastic Robot System

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Systems Science and Systems engineering 2002年第2期11卷 158-163页

作者： WANG Huidepartment of Mathematics, harbin institute of technology, {2. 150080, china department of Mathematics Harbin Institute of Technology Harbin 150080 China

In this paper, we discuss a robot system formulated as a vibrating elastic system. By regarding the damping coefficient of structure as the control variable and adjudging its optimality by norm minimum, we have proved the existence, the uniqueness and the approximation of the optimal control element by utilizing space L2.0,l) 's the reflexivity, the smoothness and the strict convexity.

关键词： robot elastic system norm minimum optimal control

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High Temperature Deformation of Al_2._3/Cu Composites

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Journal of Materials Science & technology 2001年第3期17卷 325-328页

作者： Jianjun WU. Yun ZHANG, Yanfei JIANG and Meiyun XUE department of Material Science and engineering, Hebei University of {2., Tianjin 300130, china Tingquan LEI School of Materials Science and engineering, harbin institute of technology, Uarbin 15000 Hebei Univ Technol Dept Mat Sci & Engn Tianjin 300130 Peoples R China harbin Inst Technol Sch Mat Sci & Engn Harbin 150006 Peoples R China

This work concerns with the high temperature deformation of internally oxidized Al2.3/Cu composites. The investigation revealed that dispersive alumina can obstruct dislocation sliding and define the subgrain size thereby improve significantly the strength of the materials at high temperature. The sliding of dislocations is a main deformation mechanism in the given temperature range. The sliding of grain boundary and diffusive creep play important roles at high temperature and low strain rate. The dispersoids can raise the recrystallization temperature to higher than 12.3 K. Dynamic recovery is a main softening way under the experimental conditions. Higher deformation rate and lower deformation temperature imply a higher flow stress.

关键词： High Temperature Deformation of Al2.3/Cu Composites Cu Al

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Theoretical calculation of the finishing rolling impact work in non-quenched and tempered Si-Mn steel

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Science china(Technological Sciences) 2006年第2期49卷 137-146页

作者： LIU Zhilin1, LIN Cheng1 & WANG Ping2.1. department of Materials and Chemical engineering, Liaoning {2. of technology, Jinzhou 12.001, china 2. Mechanical department, Armor technique {2. of PLA, Changchun 130117, china department of Materials Chemical engineering Liaoning Institute of Technology Jinzhou 121001 China Mechanical department Armor technique Institute of PLA Changchun 130117 China

Based on the hot-continuous rolling technology, the finishing rolling impact work α k of the non-quenched and tempered Si-Mn steel is theoretically calculated with the covalent electron number nA of the strongest bond in alloying phases, and the smallest interface electron density difference Δρ of alloying phase interface and the number of atom states σ which keep the interface electron density continuous. Calculations show that the solution strengthening, the precipitation strengthening, and the interface strengthening will result in the decrease of the finishing rolling impact work α k, and the effects of the number of atom states σ which keep the interface electron density continuous on the finishing rolling impact work α k are different. Taking the impact work and the number of atom states σ 0 keeping the electron density continuous of the phase interface α-Fe/α-Fe-C between α-Fe and α-Fe-C as reference values, the impact work of the interface will increase when σ of some interface is larger than σ 0; otherwise, the impact will decrease. Therefore, the finishing rolling impact work α k can be calculated with the impact value of the refined α-Fe matrix and the influence amounts caused by the solution strengthening, the precipitation strengthening, the interface strengthening, and the number of atom states σ which keep the interface electron density continuous. The calculated results agree well with the measured ones. In this paper, the effect of S on the impact work is also discussed.

关键词： electron structure parameters, non-quenched and tempered steel, impact work and calculation.

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Structure and Pozzolanic Activity of Calcined Coal Gangue during the Process of Mechanical Activation

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Journal of Wuhan University of technology(Materials Science) 2009年第2期24卷 326-329页

作者：郭伟 department of Material engineering Yancheng Institute of Technology institute of Material Science and engineering Nanjing University of Technology

On the basis of analyzing coal gangue＇s chemical and mineral compositions, the structure change of coal gangue during the mechanical activation was investigated by XRD, FTIR, NMR, and the mechanical strength of the cement doped coal gangue with various specific surface area was tested. The experimental results indicate that, the lattice structure of metakaolin in coal gangue samples calcined at 700 ℃ disorganizes gradually and becomes disordered, and the lattice structure of α-quartz is distorted slightly. The pozzolanic activity of the coal gangue increases obviously with its structural disorganization.

关键词： coal gangue mechanical activation structure NMR tetrahedron

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Early Hydration of Composite Cement with Thermal Activated Coal Gangue

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Journal of Wuhan University of technology(Materials Science) 2010年第1期25卷 162-166页

作者：郭伟 department of Material engineering Yancheng Institute of Technology institute of Material Science and engineering Nanjing University of Technology

Composite cement samples were prepared by mixing clinker, gypsum with burnt coal gangues which was calcined at various temperatures. The mechanical strength and Ca（OH）2.content in the cement paste were tested, and the paste composition and microstructure were analyzed by thermogravimetry-differential thermal analysis （TG-DSC）, X-ray diffraction（XRD）, scanning electronic microscopy （SEM） and pore structure analysis. Results demonstrate that the thermal activated coal gangue could accelerate the early hydration of cement clinker obviously, which promotes the gangue hydration itself. The early hydrated products of the cement are C-S-H gel, Ca（OH）2.and AFt. The cement with 30% （in mass） the gangue exhibits higher mechanical strength, and among all the cement samples the one with the gangue burnt at 700 ℃ displays the highest hydration rate, mechanical strength, the most gel pores and the lowest total porosity.

关键词： blended cement hydration microstructure hydration product

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A two-dimensional study on natural convection and heat transfer in the enclosure with heat transfer and radiation coupled in natural convection

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Science china(Technological Sciences) 2010年第4期53卷 991-999页

作者： ZHAN NaiYan1,2.YANG Mo1 & XU PeiWei2.1 College of Power engineering,University of Shanghai for Science and technology,Shanghiai 2.0093,{2. 2.department of environmental engineering,Jilin Architectural and Civil engineering institute,Changchun 13002.,{2. 1. College of Power engineering University of Shanghai for Science and Technology Shanghiai 200093 China2. Department of Environmental Engineering Jilin Architectural and Civil Engineering Institute Changchun 130021 China

Numerical investigation using SIMPLE algorithm with QUICK scheme for natural convection and heat transfer in the enclosure bounded by a solid wall and with heat transfer and radiation coupled in natural convection has been *** various parameters are:Rayleigh number(from 103 to 105),dimensionless conductivity of bounding wall(from 0 to 100),dimensionless wall thickness(from 0 to 0.6) and radiation emissivity of all surfaces(from 0 to 1).The results suggest that flow and heat transfer are influenced by *** is a dominant action on flow and heat *** increase of the thermal conductivity of wall,flow and heat transfer turn *** temperature distribution changes *** the thermal conductivity of wall is over a certain critical number,the increasing trend of flow and heat transfer may *** increase of enclosure wall thickness,flow and heat transfer turn *** the enclosure wall thickness is over a certain critical number,the flow and heat transfer will turn slow.

关键词： conduction natural convection radiation couple numerical simulation

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