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Factorial Experimental Design to Study the Effects of Layers and Fiber Content on Concrete Flexural Behavior
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作者 Dumbiri H. Odia 《Open Journal of Civil Engineering》 CAS 2023年第1期83-102,共20页
Experimentation has come a long in helping researchers achieve breakthroughs in their different scientific areas and engineering happens to be one of those areas with the most impact from experimental advancement. The... Experimentation has come a long in helping researchers achieve breakthroughs in their different scientific areas and engineering happens to be one of those areas with the most impact from experimental advancement. The need for valid experimental results free from biases and confounding conclusions has prompted the development of new experimental techniques that takes consideration of all applicable factor and combinations in providing answers on a research topic, and the Factorial Experimental design credited to Sir Ronald Fisher is one technique yielding highly valid results. This paper uses the factorial design of experiments to research the flexural impact of polyvinyl acetate fiber and layered concrete in construction. The experiment considered two levels of fiber contents and two levels of layers, and prepared samples with all combinations of the variable factors. The samples were tested after 7 days from casting for flexural strength and an advance statistical analysis was performed on the flexural responses of the samples using R-program. The results from the analyses revealed the significance of the variables to the flexural strength of the samples, as well as their interactions. The experiment concluded that based on the number of layers and fiber content used for the experiment, casting concrete in layers does have a significant negative effect on the flexural strength of concrete, and the failure pattern of concrete members under flexural load in evidently influenced by the material composition of the concrete, and that it can be evidently influenced by casting the concrete in layers. 展开更多
关键词 Experimental Design Concrete Flexural Strength factorial Design of Experiments Concrete Fibers Concrete Layers
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Preliminary Study on the Low Energy Ion Beam Mediated Parameters with Fractional Factorial Design Method 被引量:2
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作者 陈雪能 黄群策 赵帅鹏 《Agricultural Science & Technology》 CAS 2010年第8期137-139,共3页
[Objective] The aim was to explore the biological effect of low energy ion beam mediated parameters with fractional factorial design method. [Method] The twin-embryos seed of autotetraploid rice DER10-04-01 was taken ... [Objective] The aim was to explore the biological effect of low energy ion beam mediated parameters with fractional factorial design method. [Method] The twin-embryos seed of autotetraploid rice DER10-04-01 was taken as the receptor material,and the Elymus dahuricus Turcz. was used as materials to provide DNA to carry out the ion beam mediated experiment. And the fractional factorial design method was used to study the parameters of low enery N+ ion beam mediated foreign genes into rice. [Result] The implantation energy,dose,DNA concentrations and immersion time of DNA showed significant biological effects on the normal growth and development of DER10-04-01,in which the biological effects of implantation dose and DNA concentrations were relatively obvious. [Conclusion] The implantation energy,dose,DNA concentrations and immersion time of DNA were major factors showing important effects on the experimental result in ion beam mediated foreign genetic materials. 展开更多
关键词 Ion beam factorial experiment design Rice with twin-embryos seedlings Elymus dahuricus Turcz.
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Partial Bell Polynomials, Falling and Rising Factorials, Stirling Numbers, and Combinatorial Identities
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作者 Siqintuya Jin Bai-Ni Guo Feng Qi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第9期781-799,共19页
In the paper,the authors collect,discuss,and find out several connections,equivalences,closed-form formulas,and combinatorial identities concerning partial Bell polynomials,falling factorials,rising factorials,extende... In the paper,the authors collect,discuss,and find out several connections,equivalences,closed-form formulas,and combinatorial identities concerning partial Bell polynomials,falling factorials,rising factorials,extended binomial coefficients,and the Stirling numbers of the first and second kinds.These results are new,interesting,important,useful,and applicable in combinatorial number theory. 展开更多
关键词 Connection EQUIVALENCE closed-form formula combinatorial identity partial Bell polynomial falling factorial rising factorial binomial coefficient Stirling number of the first kind Stirling number of the second kind problem
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Periodic, Irrational and Transcendental Numbers in the Factorial Series
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作者 István Lénárt 《Journal of Applied Mathematics and Physics》 2022年第2期558-575,共18页
The main aim of the article is to investigate the irrational and transcendental properties of certain real numbers by means of the factorial series and the factorial number system. The difference between the factorial... The main aim of the article is to investigate the irrational and transcendental properties of certain real numbers by means of the factorial series and the factorial number system. The difference between the factorial series and the factorial system is that the factorial series does not set an upper bound at a given place after the radix point, while in the factorial system (i – 1) is the maximal possible value for r<sub>i</sub> after the radix point. I give an extended definition of periodic numbers, and show the relationship between periodic and irrational numbers. I prove the transcendence of e by means of the factorial series and the factorial number system. 展开更多
关键词 factorial Series factorial Number System Periodic Numbers Long Division Periodic and Irrational Property Transcendence of e
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Lightweight design of 45000r/min spindle using full factorial design and extreme vertices design methods 被引量:7
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作者 PARK Seong-jin LEE Choon-man HWANG Young-kug 《Journal of Central South University》 SCIE EI CAS 2011年第1期153-158,共6页
Factors for determining the spindle size are the shaft diameter, positions of bearing and motor, and entire length of the spindle. Then, it is important to find the assembling of the optimal design variables, which sa... Factors for determining the spindle size are the shaft diameter, positions of bearing and motor, and entire length of the spindle. Then, it is important to find the assembling of the optimal design variables, which satisfy the stiffimss and rotational speed required to the spindle. A general full factorial design method was used to verify some factors that affect the natural frequency of a spindle. It is verified that the shorter shaft length and bearing span length represent the higher natural frequency, and there are some effects according to the change in the levels of factors. The detailed spindle dimension is determined by applying an EVD method, which can define the optimal bearing position through considering the limiting condition. Based on the estimated regression model, the optimal spindle size and bearing distance that can improve the primary natural frequency are obtained, and the influence of design factors on the natural frequency is also analyzed. 展开更多
关键词 high-speed spindle extreme vertices design natural frequency lightweight design full factorial design
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Factorial study of moxibustion in treatment of diarrhea-predominant irritable bowel syndrome 被引量:5
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作者 Ji-Meng Zhao Lu-Yi Wu +10 位作者 Hui-Rong Liu Hong-Yi Hu Jia-Ying Wang Ren-Jia Huang Yin Shi Shan-Ping Tao Qiang Gao Ci-Li Zhou Li Qi Xiao-Peng Ma Huan-Gan Wu 《World Journal of Gastroenterology》 SCIE CAS 2014年第37期13563-13572,共10页
AIM: To identify an appropriate therapeutic regimen for using aconite cake-separated moxibustion to treat diarrhea-predominant irritable bowel syndrome (D-IBS).
关键词 Diarrhea-predominant irritable bowel syndrome Aconite cake-separated moxibustion factorial design Moxibustion quantity Clinical research
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Removal of Copper Ions from Acid Mine Drainage Wastewater Using Ion Exchange Technique: Factorial Design Analysis 被引量:7
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作者 R. W. Gaikwad R. S. Sapkal V. S. Sapkal 《Journal of Water Resource and Protection》 2010年第11期984-989,共6页
A factorial experimental design method was used to examine the “Cu2+” removal from acid mine drainage wastewater by ion exchange technique. Ion Exchange technique is preferred because of reduced sludge generation co... A factorial experimental design method was used to examine the “Cu2+” removal from acid mine drainage wastewater by ion exchange technique. Ion Exchange technique is preferred because of reduced sludge generation compared to conventional treatment techniques and better decontamination efficiency from highly diluted solutions. Factorial design of experiments is employed to study the effect of four factors pH (3, 5, and 6), flow rate (5, 10, 15 L/hr), resin bed height (20, 40 and 60 cm) and initial concentration of the metal (100, 150 and 200 mgl-1) at three levels. The efficiency of metal removal was determined after 100 min of treatment. Main effects and interaction effects of the four factors were analyzed using statistical techniques. A regression model was recommended and it was found to fit the experimental data very well. The results were analyzed statistically using the Student’s t-test, analysis of variance, F-test and lack of fit to define most important process variables affecting the percentage “Cu2+” removal. In this study , pH was thus found to be the most important variable. 展开更多
关键词 Acid MINE Drainage Ion Exchange HEAVY Metal Copper REMOVAL factorial Design of Experiments
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Evaluation of significant manufacturing parameters in lost foam casting of thin-wall Al-Si-Cu alloy using full factorial design of experiment 被引量:4
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作者 Hassan JAFARI Mohd Hsbullah IDRIS Amirreza SHAYGANPOUR 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第10期2843-2851,共9页
Controlling process parameters of lost foam casting (LFC) enables this process to produce defect-free complex shape castings. An experimental investigation on lost foam casting of an A1-Si-Cu cast alloy was carried ... Controlling process parameters of lost foam casting (LFC) enables this process to produce defect-free complex shape castings. An experimental investigation on lost foam casting of an A1-Si-Cu cast alloy was carried out. The effects of pouting temperature, slurry viscosity, vibration time and sand size on surface finish, shrinkage porosity and eutectic silicon spacing of thin-wall casting were investigated. A full two-level factorial design of experimental technique was used to identify the significant manufacturing factors affecting the properties of casting. Pouring temperature was found as the most significant factor affecting A1-Si-Cu lost foam casting quality. It was shown that flask vibration time interacted with pouring temperature influenced euteetic silicon spacing and porosity percentage significantly. The results also revealed that the surface quality of the samples cast in fine sand moulds at higher pouring temperatures was almost unchanged, while those cast in coarse sand moulds possessed lower surface qualities. Furthermore, variation in slurry viscosity showed no significant effect on the evaluated properties compared to other parameters. 展开更多
关键词 Al-Si-Cu alloy lost foam casting full factorial design surface finish POROSITY silicon spacing
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Cronbach's a reliability, concurrent validity, and factorial structure of the Death Depression Scale in an Iranian hospital staff sample 被引量:5
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作者 Mahboubeh Dadfar David Lester 《International Journal of Nursing Sciences》 2017年第2期135-141,共7页
Objective: Death depression is an important component in the process of death and dying. Death depression is the second element of death. Depression is one of the important features in death distress. The aim of this ... Objective: Death depression is an important component in the process of death and dying. Death depression is the second element of death. Depression is one of the important features in death distress. The aim of this study was to explore the performance of the Farsi version of the Death Depression Scale with an Iranian convenience sample of nurses (n =106).Methods: Nurses were selected using a convenience sampling method, and completed the Death Depression Scale (DDS), Death Concern Scale (DCS), Collett-Lester Fear of Death Scale (CLFDS), Reasons for Death Fear Scale (RDFS), Templer's Death Anxiety Scale (DAS), and Death Obsession Scale (DOS). Results: The results of exploratory factor analysis on DDS identified 4 factors (56.16%of variance). Factor 1 labeled"Death sadness", Factor 2 labeled"Death finality/end and Death dread/fear", Factor 3 labeled"Death despair and Death depression", and Factor 4 labeled"Death loneliness". Cronbach's a coefficient was 0.84, Spearman-Brown coefficient 0.85, and Guttman Split-Half coefficient 0.81 The DDS correlated 0.40 with the DCS, 0.39 with the CLFDS, 0.50 with the DAS, 0.35 with the RDFS, and 0.44 with the DOS, indicating good construct and criterion-related validity. Concurrent validity for the DDS with the other scales were significant. Conclusions: The DDS has good validity and reliability, and it can use in clinical and research settings. 展开更多
关键词 Death Depression Scale(DDS) RELIABILITY Validity factorial structure Nurses HOSPITAL
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Parameters studies for rail wear in high-speed railway turnouts by unreplicated saturated factorial design 被引量:3
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作者 XU Jing-mang WANG Ping +2 位作者 MA Xiao-chuan QIAN Yao CHEN Rong 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第4期988-1001,共14页
Rail wear is one of the main reasons for reducing the service life of high-speed railway turnouts in China. The rail wear characteristics of high-speed railway turnouts are influenced by a large number of input parame... Rail wear is one of the main reasons for reducing the service life of high-speed railway turnouts in China. The rail wear characteristics of high-speed railway turnouts are influenced by a large number of input parameters of the complex train-turnout system. To reproduce the actual operation conditions of railway turnouts, random distributions of these inputs need to be considered in rail wear simulation. For a given nominal layout of the high-speed railway turnout, 19 input parameters for rail wear simulation in high-speed railway turnouts are investigated based on orthogonal design of experiment. Three dynamic responses(wheel-rail friction work, normal contact force and size of contact patch) are defined as observed values and the significant factors(direction of passage, axle load, running speed, friction coefficient, and wheel and rail profiles) are determined by two unreplicated saturated factorial design methods, including the half-normal probability plot method and Dong 93 method. As part of the associated rail wear simulation, the influence of the wear models and the local elastic deformation on the rail wear was separately investigated. The calculation results for the wear models are quite different, especially for large creep mode. The local elastic deformation has a large effect on the sliding speed and rail wear and needs to be considered in the rail wear simulation. 展开更多
关键词 HIGH-SPEED RAILWAY turnouts RAIL WEAR unreplicated saturated factorial design WEAR simulation
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Factorial analysis on forest canopy density restoration in the burned area of northern Great Xing'an Mountains, China 被引量:2
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作者 XIEFu-ju XIAODu-ning +2 位作者 LIXiu-zhen WANGXu-gao SHIBao-dong 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第2期125-131,共7页
The restoration of forest landscape has drawn much attention since thecatastrophic fire took place on the northern slope of Great Xing'an Mountains in 1987. Forest canopydensity, which has close relation to forest... The restoration of forest landscape has drawn much attention since thecatastrophic fire took place on the northern slope of Great Xing'an Mountains in 1987. Forest canopydensity, which has close relation to forest productivity, was selected as a key factor to find howmuch the forest quality was changed 13 years after fire, and how fire severity, regeneration way andterrain factors influenced the restoration of forest canopy density, based on forest inventory datain China, and using Kendall Bivariate Correlation Analysis, and Distances Correlation Analysis. Theresults showed that fire severity which was inversely correlated with forest canopy density gradewas an initial factor among all that selected. Regeneration way which did not remarkably affectforest canopy density restoration in short period, may shorten the cycle of forest succession andpromote the forest productivity of conophorium in the future. Among the three terrain factors, theeffect of slope was the strongest, the position on slope was the second and the aspect was the last. 展开更多
关键词 forest fire burned area productivity restoration forest canopy density factorial analysis kendall correlation analysis
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Optimization of hydrothermal synthesis of H-ZSM-5 zeolite for dehydration of methanol to dimethyl ether using full factorial design 被引量:3
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作者 Samaneh Hosseini Majid Taghizadeh Ali Eliassi 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第3期344-351,共8页
H-ZSM-5 zeolite was synthesized by hydrothermal method. The effects of different synthesis parameters, such as hydrothermal crystallization temperature (170-190 ℃) and Si/A1 molar ratio (100-150), on the catalyti... H-ZSM-5 zeolite was synthesized by hydrothermal method. The effects of different synthesis parameters, such as hydrothermal crystallization temperature (170-190 ℃) and Si/A1 molar ratio (100-150), on the catalytic performance of the dehydration of methanol to dimethyl ether (DME) over the synthesized H-ZSM-5 zeolite were studied. The catalysts were characterized by N2 adsorption-desorption, XRD, NH3-TPD, TGA/DTA, and SEM techniques. The full factorial design of experiments was applied to the synthesis of H-ZSM-5 zeolite and the effects of synthesis conditions and their interaction on the yield of DME as the response variable were determined. Analysis of variance showed that two variables and their interaction significantly affected the response. According to the experimental results, the optimized catalyst prepared at 170℃ with the Si/A1 molar ratio of 100 showed the best catalytic performance among the tested H-ZSM-5 zeolite. 展开更多
关键词 full factorial design H-ZSM-5 synthesis methanol dehydration dimethyl ether
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Multiple Factorial Analysis of Symbolic Data 被引量:3
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作者 Barnabé Tang Ahanda Jean Gérard Aghoukeng Jiofack +1 位作者 Romain Germain Nzangué Gilbert Hapi Mbiakop 《Applied Mathematics》 2012年第12期2148-2154,共7页
This document presents an extension of the multiple factorial analysis to symbolic data and especially to space data. The analysis makes use of the characteristic coding method to obtain active individuals and the rec... This document presents an extension of the multiple factorial analysis to symbolic data and especially to space data. The analysis makes use of the characteristic coding method to obtain active individuals and the reconstitutive coding method for additional individuals in order to conserve the variability of assertion objects. Traditional analysis methods of the main components are applied to coded objects. Certain interpretation aids are presented after the coding process. This method was applied to poverty data. 展开更多
关键词 SYMBOLIC OBJECT ASSERTION OBJECT MULTIPLE factorial ANALYSIS Principle Components ANALYSIS Poverty
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Study on seismic performance enhancement in bridges based on factorial analysis 被引量:1
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作者 Abey ET Somasundaran TP Sajith AS 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2017年第1期181-198,共18页
The seismic performance of bridges depends on the ductile behavior of its column, as the deck and other substructural components except pile foundations are normally designed to be elastic to facilitate bridge retrofi... The seismic performance of bridges depends on the ductile behavior of its column, as the deck and other substructural components except pile foundations are normally designed to be elastic to facilitate bridge retrofitting. Codes such as AASHTO, Caltrans, IRC: 112 etc. give guidelines for the seismic performance enhancement of columns through ductile detailing. In the present study, a methodology for the seismic performance enhancement of bridges is discussed by using a "Parameter-Based Influence Factor" (PIF) developed from factorial analysis. The parameters considered in the factorial analysis are: percentage of longitudinal reinforcement (Pt), compressive strength of concrete (f'c), yield strength of steel (fy), spacing of lateral ties (5) and column height (/4). The influence of each parameter and their combination on the limit states considered is estimated. Pushover analysis is used to evaluate the capacity of columns, considering shear failure criteria. A total of 243 (35 combinations) analysis results are compiled to develop 'PIF' used in the performance enhancement process. The study also encompasses other sub-objectives such as evaluating the discrepancies in using the Importance Factor (/) in designing bridges of varied functional importance; and estimating the aspect ratio and slenderness ratio values of bridge columns for its initial sizing. 展开更多
关键词 bridge retrofitting column capacity factorial analysis performance enhancement seismic performance
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Systematic Analysis of Carbon Dioxide Activation of Waste Tire by Factorial Design 被引量:1
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作者 P.P.M.Fung W.H.Cheung G.McKay 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第3期497-504,共8页
In this study, waste tire was used as raw material for the production of activated carbons through pyrolysis. 'Fire char was first produced by carbomzation at 550℃ under nitrogen. A two tactortal design was used to ... In this study, waste tire was used as raw material for the production of activated carbons through pyrolysis. 'Fire char was first produced by carbomzation at 550℃ under nitrogen. A two tactortal design was used to optimize the production of activated carbon from tire char. The effects of several factors controlling the activation process, such as temperature (.830-930℃), time (2-6h) and percentage ot carbon dioxide (70%-100%) were investigated. The production was described mathematically as a function of these three factors. First order modeling equations were developed for surface area, yield and mesopore volume. It was concluded that the yield, BET surface area and mesopore volume of activated carbon were most sensitive to activation temperature and time while percentage of carbon dioxide in the activation gas was a less significant factor. 展开更多
关键词 activated carbon waste tire factorial design carbon dioxide
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Evaluation of the Factorial Method for Determination of Energy Expenditure in 16 Young Adult Women Living in China 被引量:1
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作者 LIU JianMin PIAO JianHua +2 位作者 SUN Rui TIAN Ying YANG XiaoGuang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2011年第4期357-363,共7页
Objective The present study aimed to evaluate the accuracy of the factorial method for estimating energy needs in individuals living in China.Methods Sixteen healthy female adults aged 22.1±1.2 years with a body ... Objective The present study aimed to evaluate the accuracy of the factorial method for estimating energy needs in individuals living in China.Methods Sixteen healthy female adults aged 22.1±1.2 years with a body mass index (kg/m 2) of 20.4±1.7 were selected as subjects.In free-living conditions,energy expenditure (EE) was determined by using the factorial method.At the same time,the doubly labeled water method (DLW) was also used to measure energy expenditure of the subjects and served as the criterion method.EE predicted by the factorial method (EE factorial) was compared with the simultaneous measurement of EE by the validated DLW method (EE DLW).Results There was excellent agreement between EE factorial (7.46±0.59 MJ/d) and EE DLW (7.64 ± 0.49 MJ/d),with a difference of-2.6±4.9% (-0.18±0.36 MJ/d).No significant differences were found between the two methods.EE factorial was highly correlated with EE DLW (r=0.795,P0.001) and a good agreement for individuals was found by using the Bland and Altman test.Conclusion The factorial method gives satisfactory estimates of EE for both groups and individuals living in China. 展开更多
关键词 Energy expenditure Chinese adults factorial method Doubly labeled water
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The spatial multiscale variability of heavy metals based on factorial kriging analysis: A case study in the northeastern Beibu Gulf 被引量:4
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作者 ZHAO Jianru CHU Fengyou +4 位作者 JIN Xianglong WU Qingsong YANG Kehong GE Qian JIN Lu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第12期137-146,共10页
Factorial kriging analysis is applied to the research on the spatial multiscale variability of heavy metals in submarine. It is used to analyze the multiscale spatial structures of seven heavy metals, Ni, Cu, Zn, Pb, ... Factorial kriging analysis is applied to the research on the spatial multiscale variability of heavy metals in submarine. It is used to analyze the multiscale spatial structures of seven heavy metals, Ni, Cu, Zn, Pb, Cr, As and Cd in the surface sediment from the northeastern of Beibu Gulf, identify and separate spatial variations at different scales of heavy metals, and discuss the provenance of heavy metals and the influencing factors. The results show that the existence of three-scale spatial variations those consist of nugget effect, a spherical structure with range of 30 km(short-range scale) and a spherical structure with range of 140 km(long-range scale) in the linear model of coregionalization fitted. The spatial distribution features of seven heavy metals at short-range scale reflect "spot-like" or "stripe-like" local-scale spatial variations; the spatial distribution features of the seven heavy metals at long-range scale represent "slice-like" regional-scale spatial variations. At local scale, Zn, Cr, Ni,Cu, Pb and Cd are derived primarily from parent materials of Hainan Island, Leizhou Peninsula and Guangxi land, whose spatial distribution characteristics are controlled by granularity of sediments, while As is influenced dominantly by human pollution components from Hainan Island and Leizhou Peninsula. At regional scale, Zn,Cr, Ni and Cu originate primarily from parent rock materials of Leizhou Peninsula and Hainan Island, secondly from Guangxi land; As originated primarily from parent rock materials from Hainan Island, secondly from Leizhou Peninsula and Guangxi land. These metals are transported and migrated with sediments dominated by the anticlockwise circulation of Beibu Gulf year-round, deposited in "convergence center", forming the whole sedimentary pattern in direction of NWW-NNW at regional scale. The difference in distribution type between As and other metals at regional scale is mainly due to their different geochemical behavior. 展开更多
关键词 spatial multiscale variability heavy metals factorial kriging analysis sediments northeastern Beibu Gulf
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Methodology of factorial design deriving guidelines for simulation of growth curve and production of sugars by Spirulina (Arthrospira) maxima 被引量:1
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作者 NIE Zhen yuan XIA Jin lan LEVERT J.M. 《Journal of Central South University of Technology》 EI 2001年第4期228-233,共6页
It is practical, economic and sometimes essential to derive rules or conclusions by performing lesser runs of experiments. In this part, a methodology based on 2 f factorial design was brought up to derive guidelines ... It is practical, economic and sometimes essential to derive rules or conclusions by performing lesser runs of experiments. In this part, a methodology based on 2 f factorial design was brought up to derive guidelines to simulate growth curve and production of sugars by Spirulina (Arthrospira) maxima . The growth curve or accumulation process of sugars was idealized by sets of straight lines limited by phase transfers of growth or accumulation of sugars. Normal analyses of the critical values of the transfers were used to derive their linear relationships with the initial conditions of the experimental factors. These linear functions were called guidelines and were used to simulate the growth curve or accumulation of sugars. Generalization of the guideline technique was determined by the kinetic limitation of nutrient nitrogen or sulfur that was dependent upon their stoichiometric deficiency directly derived from their initial values in the medium. This method uses the initial conditions of culture and does not need measurements of concentrations of nitrate, sulfate and pigments during cultivation. It is a practical and useful alternative way to trace and predict approximately the growth curve and production of sugars by S. maxima . 展开更多
关键词 factorial design GUIDELINE SIMULATION growth production of sugar ARTHROSPIRA Spirulina maxima
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Artificial Neural Network and Full Factorial Design Assisted AT-MRAM on Fe Oxides, Organic Materials, and Fe/Mn Oxides in Surficial Sediments 被引量:1
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作者 GAO Qian WANG Zhi-zeng WANG Qian LI Shan-shan LI Yu 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第6期944-948,共5页
Artificial neural network(ANN) and full factorial design assisted atrazine(AT) multiple regression adsorption model(AT-MRAM) were developed to analyze the adsorption capability of the main components in the surf... Artificial neural network(ANN) and full factorial design assisted atrazine(AT) multiple regression adsorption model(AT-MRAM) were developed to analyze the adsorption capability of the main components in the surficial sediments(SSs). Artificial neural network was used to build a model(the determination coefficient square r2 is 0.9977) to describe the process of atrazine adsorption onto SSs, and then to predict responses of the full factorial design. Based on the results of the full factorial design, the interactions of the main components in SSs on AT adsorption were investigated through the analysis of variance(ANOVA), F-test and t-test. The adsorption capability of the main components in SSs for AT was calculated via a multiple regression adsorption model(MRAM). The results show that the greatest contribution to the adsorption of AT on a molar basis was attributed to Fe/Mn(–1.993 μmol/mol). Organic materials(OMs) and Fe oxides in SSs are the important adsorption sites for AT, and the adsorption capabilities are 1.944 and 0.418 μmol/mol, respectively. The interaction among the non-residual components(Fe, Mn oxides and OMs) in SSs interferes in the adsorption of AT that shouldn’t be neglected, revealing the significant contribution of the interaction among non-residual components to controlling the behavior of AT in aquatic environments. 展开更多
关键词 Back propagation(BP) artificial neural network Full factorial design Fe/Mn oxide Organic material ATRAZINE Interaction
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Optimization of Biosurfactant Production from Glycerol by Pseudomonas Aeruginosa EQ 109 Using Factorial Design 2^3 被引量:1
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作者 Francisca Pessoa De Franca Flavia Padilha Bastos Dos Santos Lea Maria de Almeida Lopes 《Journal of Chemistry and Chemical Engineering》 2010年第10期1-12,共12页
One possible application for the excess of glycerol, which is an exceeding byproduct in biodiesel industry, was used as carbon and energy sources for bioproducts synthesis. This work aims to evaluate biosurfactant pro... One possible application for the excess of glycerol, which is an exceeding byproduct in biodiesel industry, was used as carbon and energy sources for bioproducts synthesis. This work aims to evaluate biosurfactant production from glycerol by Pseudomonas aeruginosa EQ 109 isolated from crude oil-contaminated soil. Factorial design 2^3 was utilized to optimize the amount of biosurfactant produced, by using pH (A), initial biomass concentration (B), and initial glycerol concentration (C) as independent factors. The experiments were carried out in flasks containing 100 mL of mineral medium. Biosurfactant production was monitored by increase of the emulsification of aviation kerosene (E24) and surface tension reduction (STr). The results have shown that, at pH = 7.0, in order to increase E24, variables as B and C are the most influential, leading to a maximum value of E24 = 79%, as well as for an increase of GC (GCmax = 49%). STR was the variable with the best correlation factor for the proposed linear model (R2=0.96) and its maximum value was 48%. Xfwas not significant to the model, although it was influenced by pH and C, with C = 40g/L (Xfmax = 4.56 g/L). 展开更多
关键词 BIODIESEL BIOSURFACTANT factorial design GLYCEROL Pseudomonas aeruginosa.
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