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1.
Fabric simulation is result of combining various methods that have been dramatically evolved during the decade. However, there still exist some limitations. One of the limitations in fabric simulation is lack of using fabric properties such as material, weave structure, density and so on in mass spring modeling. In knitted fabrics, this issue is more important due to their different fabric structures. In this paper, a new mesh based on loop shape for simulating 1×1 rib fabric is proposed which is called Loop mesh. By using the Loop and common meshes, 3D model of drape behavior in 18 types of knitted fabric are simulated. Results of simulation are compared with 3D shape of actual drape behavior in fabric samples which are achieved by depth camera. Results show that the Loop mesh is able to predict the drape behavior of knitted fabric with error value of 5 percent as compared with the real result. It can be found that the Loop mesh produced a closest drape shape to the actual fabric drape than other mesh models. 相似文献
2.
In-Kyun Jung Jong-Yoon Park Geun-Ae Park Mi-Seon Lee Seong-Joon Kim 《Paddy and Water Environment》2011,9(3):275-290
A grid-based, KIneMatic wave STOrm Runoff Model (KIMSTORM) is described. The model adopts the single flow-path algorithm and
routes the water balance during the storm period. Manning’s roughness coefficient adjustment function of the paddy cell was
applied to simulate the flood mitigation effect of the paddy fields for the grid-based, distributed rainfall-runoff modeling.
The model was tested in 2296 km2 dam watershed in South Korea using six typhoon storm events occurring between 2000 and 2007 with 500 m spatial resolution,
and the results were tested through the automatic model evaluation functions in the model. The average values of the Nash–Sutcliffe
model efficiency (ME), the volume conservation index (VCI), the relative error of peak runoff rate (EQp), and the absolute error of peak runoff (ETp) were 0.974, 1.016, 0.019, and 0.45 h for calibrated storm events and 0.975, 0.951, 0.029, and 0.50 h for verified storm
events, respectively. In the simulation of the flood mitigation effect of the paddy fields, the average values of the percentage
changes for peak runoff, total runoff volume, and time to peak runoff were only −1.95, −0.93, and 0.19%, respectively. 相似文献
3.
This study presents a method for the fabrication of ultrafine polymeric nanobers utilizing centrifugal and electrostatic forces simultaneously. To reduce the diameter and variability of nanofibers produced from polyacrylonitrile (PAN) and poly-L-lactic acid (PLLA), a unique electro-centrifuge spinning device was designed using rotating nozzle and collector, whereas the fabrication process (spinning head) was skillfully sealed from ambient airflow. The polymer solution was continuously delivered by a rotating nozzle and the nanofibers were collected by a rotating cylindrical collector at the same rotational speed as the nozzle. Field emission scanning electron microscope (FESEM) results demonstrated that this method has a significant effect on the quality and fineness of nanofibers. The diameters of nanobers were controlled by adjusting the rotation speed of spinning head. The effect of the rotation speed on the morphology of the nanofibers fabricated by this device was also evaluated. In order to provide a useful context for the current nanofiber production method, nanofibers obtained in this method were compared with those produced by other methods. The results show that air-sealedcentrifuge-electrospinning system (ASCES) is a facile method for the fabrication nanobers with smaller diameters and high uniform structures. 相似文献
4.
大豆灰斑病是一个多循环病害,叶、荚病情田间流行曲线均呈"S"型,(Y)1=C/1 ea-bX公式进行曲线方程拟合,拟合方程均达到显著水平.根据荚病指(x)与病粒率(y)的相关建立了荚病指与病粒率的直线回归方程,感病品种Y=3.2 0.8890X,抗病品种Y=1.223 0.7669X.根据病粒率与气象因子的相关关系建立了早熟品种和中晚熟品种灰斑病粒率预测多元回归方程,早熟品种(Y)1(%)=-0.38-0.3889X1 0.7726X2 0.7070X3,中晚熟品种(Y)2(%)=-7.08-6.37×10-2X1 1.405X2 2.694X3.预测方程在一个农场运行结果,预测病粒率与实际调查的病粒率十分接近. 相似文献
5.
《Crop Protection》1993,12(5):335-342
The timing of attack by pest insects can vary greatly both from region to region and from year to year because the rates at which insects complete their life cycles depend mainly on temperature. In addition, variation between individual insects in their rate of development can lead to a spread of activity. A simulation method, based on rates of insect development, has been produced for forecasting the timing of attack by pest insects. Variability is incorporated using the ‘same-shape property’ which implies that the coefficient of variation of the rate of insect development is independent of temperature. The method is feasible because it uses a fixed number of individuals from one generation to the next and simulates the timing of events rather than the population dynamics of the insects. The method is sufficiently flexible to allow insect resting phases to occur at the appropriate instant for each individual. Its effectiveness in predicting the behaviour of the cabbage root fly (Delia radicum), the carrot fly (Psila rosae), the bronzed blossom beetle (Meligethes aeneus) and the large narcissus fly (Merodon equestris) is demonstrated for one site in one season. To be of practical use, the method has been designed to use standard meteorological data. Estimation of soil temperatures at 6 cm and the derivation of equations for estimating diurnal variation are described in two appendices. The basis of the method is the integration of a temperature-dependent rate function over time. A third appendix describes a quicker and more accurate method of integration than that usually employed in pest forecasting work. 相似文献
6.
7.
Rice blast disease is one of the obstacles of rice production not only in Japan but throughout rice producing countries. The effects of fan-forced wind on the incidence of rice blast disease were studied in two successive seasons. Electric fans (5 KW, 110-cm blade diameter) set on the ridge of paddy fields at a height 5 m from the ground level were used to artificially generate wind. In season 1, the fan operated twice daily for 30 min periods at 11:00 pm and 4:00 am from June 15 to September 1. The blocks of the paddy fields were divided into 6 zones according to wind speed and distance from the fan. The wind speed ranged from 2.0 to >7.3 m/s. The incidence of both rice leaf and panicle blast was significantly lower in the zones receiving wind between 2.6 and 7.3 m/s; however, the zone that received a velocity >7.3 m/s was severely affected by leaf and panicle blast. The zone that received the a wind speed of 2.6 m/s or lower exhibited an inefficient reduction of leaf and panicle blast disease, but it was better than in the control fields. In season 2, a wind-forced fan was applied from June 16 to September 9, with the velocity adjusted between ca. 3.0 and 6.0 m/s. The incidence and severity of leaf and panicle blasts (chuff, rachis-branch and neck blast) were efficiently reduced in the wind-treated fields. Fan-forced wind was more effective than the application of conventional chemical fungicides for controlling rice blast disease. These data demonstrate the potential of fan-forced wind for controlling rice blast disease. 相似文献
8.
Summary The use of imazethapyr as a sprout suppressant in potatoes has been investigated. Novel radionuclide techniques were developed
to establish the patterns of uptake and movement of imazethapyr in potatoes. Protocols for tissue analysis were established
to homogenise potato tuber tissue samples, enabling radiolabel recovery by liquid scintillation counting to approach 100%.
The movement of imazethapyr was also examined in the presence of an acidic formulation of thiabendazole which caused increased
uptake. The movement of imazethapyr within the tuber was also influenced by pH and ion trapping. 相似文献
9.
In this paper, a purpose-built apparatus was used to analyze the moisture liberation of textile fabrics. Fabrics were wetted
and placed in an air-conditioned room to test the variation of weight and surface temperature during the process of moisture
liberation. Effects of textile materials and fabric structures on the velocities of moisture liberation of fabrics were analyzed;
the temperature variation and its relationship with moisture regains of fabrics in the moisture liberation were also studied.
Moisture liberation velocities of polyester and silk fabrics are much higher than that of wool and cotton fabrics. For the
same textile materials, knitted fabrics absorbed more water and thus took longer time to liberate the water. The surface temperature
of fabrics showed three stages during moisture liberation. With the decrease of moisture regain, fabric temperature decreased
gradually and jumped quickly to ambient temperature. In this way we could evaluate the moisture desorption of fabrics and
develop quick-drying fabrics with imporved moisture and thermal properties. 相似文献
10.
Inundated areas of the Mekong Delta are the most important regions for agricultural production in both Cambodia and Vietnam.
With population growth and increasing water demand in the dry season, effectively managing available water in the region is
vital for crop production. This study is aimed at developing a sub-area based modeling of flood inundation model in order
to analyze flood inundation processes in the Cambodian Mekong Delta as a basis for introducing semi-flood control for new
cropping systems such as double-rice cropping. The simulated results of the flood inundation model from 2002 to 2003 were
utilized for estimating land appearance in the dividing sub-area, and the potential of securing land for double-rice cropping
was determined based on the period of land appearance and the cropping schedule. In order to realize the available water for
double cropping, consideration of the effect of operating canal gates for controlling the early and receding inundation are
crucially necessary. By considering the operation of control gates facilities, the potential land for securing double-rice
cropping exceeded about 50 km2 compared to the 34 km2 of the actual land used for recession rice (about 30 and 20% of the total selected area, respectively). The study confirms
that the sub-area based modeling of inundation model can be a helpful tool for water management in the Cambodia Mekong Delta. 相似文献
11.
Polystyrene (PS) grafted multi-walled carbon nanotubes (MWCNTs) were well-organized as bundles by a selfassembly method in tetrahydrofuran (THF). PS was synthesized by atom transfer radical polymerization and grafted to the surface of tubes through covalent bonds. Unmodified tubes agglomerated irregularly and precipitated instantly because of poor compatibility with THF. But soluble PS provides solvent-phobic MWCNTs with suspending stability and dispersibility in the dispersant. Therefore, MWCNT-g-PS has amphiphilic property in this selective solvent and owns ability to self-assemble. Scanning and transmission electron microscope images show that self-assemblies (SAs) are columnar with a tight and ordered head and a loose tail. Their length ranges from 15 to 25 µm while width from 1.5 to 4 µm. In these super structures, tubes are regular organized and parallel arranged. Because MWCNT-g-PS has a huge rigid rod-core and multi-flexible-armed structure in the suspension, a novel micro-phase separation model is proposed to explain this behavior. There are two kinds of micro-phase separation locating on two mutual perpendicular faces on tubes. Solvent-philic/solvent-phobic interaction plays a key role in self-assembly. Moreover, a balance between buoyancy and gravity on SAs decides whether this process is finished or not. 相似文献
12.
Although madder (Rubia tinctorum) has been used as a well-known natural textile dye source for dyeing of natural fibers such as wool, silk and cotton, 100 % polyester dyeing with madder is not common. In this study, polyester samples were dyed with madder at different dyeing temperatures, from 60 °C to 130 °C, in company with 7 chemical and 5 natural mordants. Color properties and rub, light and wash fastness performances were investigated. Different shades of orange, brown, pink and reddish green colors were obtained. Dyeing at 130 °C exhibited the highest color yield, the highest chroma and the lowest lightness values. Overall, chemical mordants exhibited higher color yields than natural mordants. High wash fatness, moderate light and rub fastness levels were observed. The potassium bitartrate and gallnut, a natural mordant, exhibited the best results. The madder dyeing of polyester should be carried out at hot temperature conditions, 130 °C, in order to obtain the highest achievable color yield and chroma with the highest light and wash fastness properties. 相似文献
13.
Ash content is an important quality control parameter in milling industry. Measurement of ash content is routinely performed using standard ash analysis method in which the sample is burned at 500–600 °C for 5–6 h. However, this method is not convenient for industrial applications, and thus, rapid and reliable methods are needed to be developed. The aim of this study was to develop a new method for ash analysis to be used in wheat milling fractions by using laser induced breakdown spectroscopy (LIBS). LIBS is an optic based multi-elemental, spectroscopic method which can analyze high number of samples in a considerably short time. In the study, wheat flour, whole wheat meal and semolina samples with different ash contents were analyzed using LIBS, and the spectra were evaluated with partial least squares (PLS) method. The results were correlated with the ones taken from standard ash analysis method. Calibration graph showed good linearity with the ash content between 0.48 and 2.44%, and 0.997 coefficient of determination (R2). Limit of detection for ash analysis was calculated as 0.11%. The results indicated that LIBS is a promising and reliable method with high sensitivity for routine ash analysis in milling industry. 相似文献
14.
F.H.V. Medeiros A.W.V. Pomella J.T. de Souza G.R. Niella R. Valle R.P. Bateman D. Fravel B. Vinyard P.K. Hebbar 《Crop Protection》2010
A three-year field study was conducted in Bahia, Brazil to validate several strategies for management of witches' broom disease in cacao caused by Moniliophthora perniciosa. Treatments which were applied alone or in combination included applications of biological control fungus Trichoderma stromaticum, fungicide copper hydroxide and phytosanitary broom removal. When compared with untreated control treatments, higher pod yields and consistently lower pod losses were obtained by alternating fungicide with biocontrol application. Pod losses caused by witches' broom were also reduced by fungicide treatment or by phytosanitary broom removal when applied alone or in combination, however total pod production per tree was consistently low whenever broom removal was used as a management strategy. While application of biocontrol fungus alone was not able to reduce witches' broom on pods, it reduced vegetative broom formation and also increased the number of pod-forming flower cushions. The present study indicates that alternating fungicide copper hydroxide with biocontrol fungus T. stromaticum without expensive phytosanitary broom removal is not only a better disease management strategy in Bahia but also results in better yields and thereby better net economic returns. 相似文献
15.
This study was engaged in a new algorithm which was used to solve the problem of protein folding. The conformation of hydrophobic core of protein was key factor of structure of protein. So, in our algorithm, we set a hydrophobic core which was restricted by new aggregate. Then, the hydrophilic residues between two hydrophobic residues were ranged, the optimal conformation was gained if all residues were not overlap and continuous. The algorithm in this study can be prevented effectively falls into partially smallest energy. 相似文献
16.
Optimization of curing process for polymer-matrix composites based on orthogonal experimental method
In this paper, the orthogonal experimental method was carried out to optimize the curing process of aeronautical composite X850/T800 in autoclave process. Four important curing parameters including curing pressure, heating rate, curing temperature and heat preservation time were taken into account, and sixteen samples were fabricated to study the effects of the four parameters mentioned above on the curing quality by interlaminar properties test and microstructure analysis. The interlaminar properties and the interfacial bonding quality of these samples were studied by the short-beam three points bending test and scanning electron microscopy, respectively. Results revealed that the optimal curing process of X850/T800 composite laminate should be as follows: curing pressure of 0.6 MPa, heating rate of 1.5 °C/min, curing temperature of 160 °C, and heat preservation time of 120 min. 相似文献
17.
《Field Crops Research》1995,41(2):91-100
Vernalization treatments of 0 to 70 d initiated when 0 to 8 leaf tips were visible were applied to plants of the winter wheat (Triticum aestivum L.) cultivars Pioneer 2548 and Augusta. All plants headed irrespective of duration of vernalization. Unvernalized plants of Pioneer 2548 and Augusta had mean final leaf numbers (FLN) of 20.8 ± 1.3 and 21.7 ± 1.0, respectively. Increased duration of vernalization generally reduced FLN within an age treatment until an age-dependent point of vernalization insensitivity was reached. Estimates of the minimum days of vernalization required to reach vernalization insensitivity decreased in a linear fashion as plant age at the onset of vernalization treatment increased. The number of leaves appearing after the onset of vernalization insensitivity averaged 6.3 ± 0.5. FLN minus six appears to be a valid estimate in our experimental conditions for the onset of vernalization insensitivity, at least for plants that had six or more leaves appearing after the end of vernalization treatment. Linear regressions of FLN minus six against days of vernalization were significant for both cultivars (for treatments with six or more leaves emerging after vernalization). The Y-intercepts of the fitted regressions were close to values obtained by subtracting six from FLN of unvernalized plants. Both intercept and slope were controlled genetically. Accumulated plant age, expressed as leaf stage, enables attainment of vernalization insensitivity, independent of, or in combination with vernalization treatment. 相似文献
18.
Carbon fiber production is a large-scale system which comprises a large number of production processes. Among the various complex production conditions, the drawing process is one of the most influential factors that affect the quality of carbon fiber. How to obtain the fittest process parameters of the drawing process is a typical multi-objective optimization problem. To address the drawbacks of mathematical programming techniques available for solving optimization problems, we propose a new synergetic immune clonal selection algorithm (SICSA) to obtain the optimal process parameters, such as the linear density, strength, and breaking elongation ratio. The main operators of the SICSA are synergetic evolution, clonal operation and non-uniform mutation. The synergetic evolution between populations adopts a “division-parallel-recombination” mode, the clonal operation searches for optimal solutions globally, and the non-uniform mutation explores optimal solutions locally and enhances the diversity of the solutions. As a result, optimal solutions which lead to reasonable distribution of the drawing ratio are obtained. We also compare the proposed SICSA with an immune algorithm and a genetic algorithm for optimizing the parameter in the drawing process. Our results show that the SICSA has the best performance in precision and convergence time. These results can serve as references and provide guidance for real production of carbon fiber. 相似文献
19.
20.
Computational efficiency has become a key issue in genomic prediction(GP) owing to the massive historical datasets accumulated. We developed hereby a new super-fast GP approach(SHEAPY) combining randomized Haseman-Elston regression(RHE-reg) with a modified Algorithm for Proven and Young(APY) in an additive-effect model, using the former to estimate heritability and then the latter to invert a large genomic relationship matrix for best linear prediction. In simulation results with varied sizes of training population, GBLUP, HEAPY|A and SHEAPY showed similar predictive performance when the size of a core population was half that of a large training population and the heritability was a fixed value, and the computational speed of SHEAPY was faster than that of GBLUP and HEAPY|A. In simulation results with varied heritability, SHEAPY showed better predictive ability than GBLUP in all cases and than HEAPY|A in most cases when the size of a core population was 4/5 that of a small training population and the training population size was a fixed value. As a proof of concept, SHEAPY was applied to the analysis of two real datasets. In an Arabidopsis thaliana F2 population, the predictive performance of SHEAPY was similar to or better than that of GBLUP and HEAPY|A in most cases when the size of a core population(2 0 0) was 2/3 of that of a small training population(3 0 0). In a sorghum multiparental population,SHEAPY showed higher predictive accuracy than HEAPY|A for all of three traits, and than GBLUP for two traits. SHEAPY may become the GP method of choice for large-scale genomic data. 相似文献