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Genetic Parameters Evaluation of Main Reproductive Traits for the New Yorkshire Dam Line with High Prolificacy
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作者 宋忠旭 孙华 +3 位作者 彭先文 李良华 董斌科 梅书棋 《Agricultural Science & Technology》 CAS 2013年第10期1465-1467,共3页
The genetic parameters of main reproductive traits for the new Yorkshire line with high prolificacy were evaluated by multiple animal model DFREML The re- suits showed that the heritability evaluates of the total numb... The genetic parameters of main reproductive traits for the new Yorkshire line with high prolificacy were evaluated by multiple animal model DFREML The re- suits showed that the heritability evaluates of the total number of born (TNB), alive number of born (ANB), litter weigh at birth (LWB) and litter weight at age of 21 days were 0.10, 0.15, 0.09 and 0.14, respectively. The genetic correlations between these traits, for example, the correlations between TNB/ANB, NB/LWB, TNB/LW21, ANB/LWB, ANB/LW21 and LWB/LW21 were 0.87, 0.74, 0.43, 0.69, 0.59 and 0.51, respectively. 展开更多
关键词 new Yorkshire dam line with high prolificacy DFREML Variance com- ponent Genetic parameter
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Learning Bayesian network parameters under new monotonic constraints 被引量:8
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作者 Ruohai Di Xiaoguang Gao Zhigao Guo 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第6期1248-1255,共8页
When the training data are insufficient, especially when only a small sample size of data is available, domain knowledge will be taken into the process of learning parameters to improve the performance of the Bayesian... When the training data are insufficient, especially when only a small sample size of data is available, domain knowledge will be taken into the process of learning parameters to improve the performance of the Bayesian networks. In this paper, a new monotonic constraint model is proposed to represent a type of common domain knowledge. And then, the monotonic constraint estimation algorithm is proposed to learn the parameters with the monotonic constraint model. In order to demonstrate the superiority of the proposed algorithm, series of experiments are carried out. The experiment results show that the proposed algorithm is able to obtain more accurate parameters compared to some existing algorithms while the complexity is not the highest. 展开更多
关键词 Bayesian networks parameter learning new mono tonic constraint
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S Phase Cell Percentage Normalized BrdU Incorporation Rate, a New Parameter for Determining S Arrest 被引量:2
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作者 ZHAO Peng FU Juan Ling +2 位作者 YAO Bi Yun JIA Yong Rui ZHOU Zong Can 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2014年第3期215-219,共5页
In this study, a new parameter, S phase cell percentage (S fraction) normalized BrdU (SFN-BrdU) incorporation rate, was introduced to detect $ arrest. The results showed a positive linear correlation between the B... In this study, a new parameter, S phase cell percentage (S fraction) normalized BrdU (SFN-BrdU) incorporation rate, was introduced to detect $ arrest. The results showed a positive linear correlation between the BrdU incorporation rate and the S fraction in unperturbed 16HBE cells. Theoretical analysis indicated that only S arrest could result in a decrease in the SFN-BrdU incorporation rate. Additionally, the decrease in SFN-BrdU incorporation rate and the activation of DNA damage checkpoints further demonstrated that S arrest was induced by diethyl sulfate treatment of 16HBE cells. In conclusion, $FN-BrdU incorporation rate can be used to detecting S arrest. 展开更多
关键词 BRDU RATE S Phase Cell Percentage normalized BrdU Incorporation Rate a new parameter for Determining S Arrest
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Earthquake source parameters of the 2009 M_W7.8 Fiordland (New Zealand) earthquake from L-band InSAR observations
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作者 Zhenhong Li Wei Qu +1 位作者 Kateline Young Qin Zhang 《Earthquake Science》 CSCD 2011年第2期199-206,共8页
The 2009 M W 7.8 Fiordland (New Zealand) earthquake is the largest to have occurred in New Zealand since the 1931 M W 7.8 Hawke’s Bay earthquake, 1 000 km to the northwest. In this paper two tracks of ALOS PALSAR i... The 2009 M W 7.8 Fiordland (New Zealand) earthquake is the largest to have occurred in New Zealand since the 1931 M W 7.8 Hawke’s Bay earthquake, 1 000 km to the northwest. In this paper two tracks of ALOS PALSAR interferograms (one ascending and one descending) are used to determine fault geometry and slip distribution of this large earthquake. Modeling the event as dislocation in an elastic half-space suggests that the earthquake resulted from slip on a SSW-NNE orientated thrust fault that is associated with the subduction between the Pacific and Australian Plates, with oblique displacement of up to 6.3 m. This finding is consistent with the preliminary studies undertaken by the USGS using seismic data. 展开更多
关键词 InSAR new Zealand earthquake source parameter uniform slip modeling distributed slip modeling
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New Parameters of Cardiopulmonary Exercise Testing in Patients with Chronic Heart Failure: Practical Applications
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作者 P. Gibelin A. Aldossari +2 位作者 D. Bertora P. Moceri T. Hugues 《International Journal of Clinical Medicine》 2012年第6期532-537,共6页
Cardiopulmonary exercise testing (CPX) has become the cornerstone of risk stratification for heart failure patients. Peak oxygen consumption (VO2) was the first CPX variable to demonstrate prognostic value and is stil... Cardiopulmonary exercise testing (CPX) has become the cornerstone of risk stratification for heart failure patients. Peak oxygen consumption (VO2) was the first CPX variable to demonstrate prognostic value and is still the most frequently analyzed variable in clinical practice. More recently, several investigations have shown that ventilatory efficiency, typically expressed as the minute ventilation/carbon dioxide production (VE/VCO2) slope, is a strong prognostic marker in patient with HF. The majority of studies report the VE/VCO2 slope to be prognostically superior to peak VO2 which underscore the clinical importance of assessing ventilatory efficiency in HF patients. Other expressions of ventilatory inefficiency like exercise oscillatory breathing (EOB), oxygen uptake efficiency slope (OUES), end-tidal carbon dioxide pressure (PET CO2) at rest, and haemodynamic responses such as heart rate recovery (HRR) are strong predictors of outcomes in patients with heart failure (HF). So there is a need for simplified approaches that integrate the additive prognostic information from cardiopulmonary exercise testing. 展开更多
关键词 new parameters CARDIOPULMOnARY EXERCISE Testing CHROnIC HEART FAILURE
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Parameters of new three-water model based on nuclear magnetic experiment and optimization algorithm
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作者 KANG Nan HONG Xin +3 位作者 ZHANG Lihua PAN Baozhi TANG Lei ZHANG Pengji 《Global Geology》 2023年第1期57-62,共6页
Clastic rock reservoir is the main reservoir type in the oil and gas field.Archie formula or various conductive models developed on the basis of Archie’s formula are usually used to interpret this kind of reservoir,a... Clastic rock reservoir is the main reservoir type in the oil and gas field.Archie formula or various conductive models developed on the basis of Archie’s formula are usually used to interpret this kind of reservoir,and the three-water model is widely used as well.However,there are many parameters in the threewater model,and some of them are difficult to determine.Most of the determination methods are based on the statistics of large amount of experimental data.In this study,the authors determine the value of the parameters of the new three-water model based on the nuclear magnetic data and the genetic optimization algorithm.The relative error between the resistivity calculated based on these parameters and the resistivity measured experimentally at 100%water content is 0.9024.The method studied in this paper can be easily applied without much experimental data.It can provide reference for other regions to determine the parameters of the new three-water model. 展开更多
关键词 new three-water model optimization algorithm nMR water saturation rock electric parameters
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Nitrogen Nutrition Index and Its Relationship with N Use Efficiency, Tuber Yield, Radiation Use Effi ciency, and Leaf Parameters in Potatoes 被引量:6
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作者 HU Da-wei SUN Zhou-ping +2 位作者 LI Tian-lai YAN Hong-zhi ZHANG Hua 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第5期1008-1016,共9页
Knowledge about crop growth processes in relation to N limitation is necessary to optimize N management in farming system. Plant-based diagnostic method, for instance nitrogen nutrition index (NNI) were used to dete... Knowledge about crop growth processes in relation to N limitation is necessary to optimize N management in farming system. Plant-based diagnostic method, for instance nitrogen nutrition index (NNI) were used to determine the crop nitrogen status. This study determines the relationship of NNI with agronomic nitrogen use efficiency (AEN), tuber yield, radiation use efficiency (RUE) and leaf parameters including leaf area index (LAI), areal leaf N content (NJ and leaf N concentration (N0. Potatoes were grown in field at three N levels: no N (N 1), 150 kg N ha^-1 (N2), 300 kg N ha^-1 (N3). N deficiency was quantified by NNI and RUE was generally calculated by estimating of the light absorbance on leaf area. NNI was used to evaluate the N effect on tuber yield, RUE, LAI, NAL, and NL. The results showed that NNI was negatively correlated with AEN, N deficiencies (NNI〈 1) which occurred for N 1 and N2 significantly reduced LAI, NL and tuber yield; whereas the N deficiencies had a relative small effect on NAL and RUE. To remove any effect other than N on these parameters, the actual ratio to maximum values were calculated for each developmental linear relationships were obtained between NNI and tuber RUE to NNI. stage of potatoes. When the NNI ranged from 0.4 to 1, positive yield, LAI, NL, while a nonlinear regression fitted the response of 展开更多
关键词 POTATO nitrogen nutrition index n use efficiency tuber yield radiation use efficiency leaf parameters
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Investigation of ductile iron casting process parameters using Taguchi approach and response surface methodology 被引量:3
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作者 A. Johnson Santhosh A. R. Lakshmanan 《China Foundry》 SCIE 2016年第5期352-360,共9页
To find the optimized levels of various casting parameters in the ductile iron casting, various casting defects and the rejection rate were observed from a medium scale foundry. The controlled values of different cast... To find the optimized levels of various casting parameters in the ductile iron casting, various casting defects and the rejection rate were observed from a medium scale foundry. The controlled values of different casting parameters such as pouring temperature, inoculation, carbon equivalent, moisture content, green compression strength, permeability and mould hardness were selected. Three different melts of metal with 0.4wt.%, 0.6wt.%, and 0.8wt.% inoculation (Fe-Si-Mg alloy and post inoculant) were produced using a 1-ton capacity coreless medium frequency induction furnace. L-27 orthogonal array with 3-level settings were chosen for the analysis. Responses for each run were observed. The signal-to-noise (S/N) ratio for each run was calculated using the Taguchi approach, and the optimized levels of different casting parameters were identified based on the SIN ratio. The analysis of variance for the casting acceptance percentage concludes that inoculation is the most significant factor affecting the castings' quality with a contribution percentage of 44%; an increase in inoculation results in a significant improvement in acceptance percentage of ductile iron castings. The experiment results showed that with the optimized parameters, the rejection rate was reduced from 16.98% to 6.07%. 展开更多
关键词 optimized levels casting parameters S/n ratio Taguchi approach AnOVA ‘F’-Test
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Investigation of the performance of CF3I/c-C4F8/N2 and CF3I/c-C4F8/CO2 gas mixtures from electron transport parameters 被引量:5
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作者 Ruishuang ZHONG Su ZHAO +4 位作者 Dengming XIAO Hui WANG Xiuchen JIANG Zhongmin YU Yunkun DENG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第5期44-51,共8页
CF3I gas mixtures have attracted considerable attention as potential environmentally-friendly alternatives to SF6 gas,owing to their excellent insulating performance.This paper attempts to study the CF3I ternary gas m... CF3I gas mixtures have attracted considerable attention as potential environmentally-friendly alternatives to SF6 gas,owing to their excellent insulating performance.This paper attempts to study the CF3I ternary gas mixtures with c-C4F8 and buffer gases N2 and CO2 by considering dielectric strength from electron transport parameters based on the Boltzmann method and synergistic effect analysis,compared with SF6 gas mixtures.The results confirm that the critical electric field strength of CF3I/c-C4F8/70%CO2 is greater than that of 30%SF6/70%CO2 when the CF3I content is greater than 17%.Moreover,a higher content of c-C4F8 decreases the sensitivity of gas mixtures to an electric field,and this phenomenon is more obvious in CF3I/c-C4F8/CO2 gas mixtures.The synergistic effects for CF3I/c-C4F8/70%N2 were most obvious when the c-C4F8 content was approximately 20%,and for CF3I/c-C4F8/70%CO2 when the c-C4F8 content was approximately 10%.On the basis of this research,CF3I/c-C4F8/70%N2 shows better insulation performance when the c-C4F8 content is in the15%–20%range.For CF3I/c-C4F8/70%CO2,when the c-C4F8 content is in the 10%–15%range,the gas mixtures have excellent performance.Hence,these gas systems might be used as alternative gas mixtures to SF6 in high-voltage equipment. 展开更多
关键词 CF3I/c-C4F8/n2 gas mixtures CF3I/c-C4F8/CO2 gas mixtures Boltzmann method electron transport parameters synergistic effect
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Effect of sintering parameters on powder injection molded Ti(C, N)-based cermets
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作者 范畴 熊惟皓 《中国有色金属学会会刊:英文版》 CSCD 2005年第S3期153-156,共4页
Effect of two-stage sintering parameters such as heating rate, top sintering temperature and holding time, sintering temperature and holding time at the second stage on relative density, transverse rupture strength(TR... Effect of two-stage sintering parameters such as heating rate, top sintering temperature and holding time, sintering temperature and holding time at the second stage on relative density, transverse rupture strength(TRS) and microstructures of powder injection molded Ti(C, N)-based cermets were investigated, by means of Archimedes’s method, three-point bending test and micrographic analysis. The results show that the optimum sintering cycle for powder injection molded Ti(C, N)-based cermets comprises rapid heating (10℃/min) at low temperatures, slow heating (5℃/min) at intermediate temperatures, holding at the highest sintering temperature (1420℃) for a short time (10min), and holding at the second stage (1360℃) for a longer time (6h) to avoid grain coarsening, and that its TRS reaches 624MPa, and there are little pores in their microstructures. 展开更多
关键词 Ti(C n)-based cermets POWDERInG injection molding sintering parameters relative density transverse rupture strength
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Adaptive Anti-Synchronization Between Different Chaotic/Hyperchaotic Systems with Fully Unknown Parameters
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作者 唐漾 方建安 《Journal of Donghua University(English Edition)》 EI CAS 2008年第5期489-494,共6页
The anti-synchronization between different chaotic/hyperchaotic systems with fully unknown parameters is considered in detail. Based on Lyapunov stability theory, the adaptive control schemes and parameter update rule... The anti-synchronization between different chaotic/hyperchaotic systems with fully unknown parameters is considered in detail. Based on Lyapunov stability theory, the adaptive control schemes and parameter update rules are designed in this paper. Two numerical examples show the effectiveness and feasibility of the proposed method. 展开更多
关键词 AnTI-SYnCHROnIZATIOn unknown parameters new chaotic system h yperchaotic system adaptive synchronization
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Effects of Nitrogen Amount on the Photosynthesis Parameters of Summer Millet in North China
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作者 Qing ZHAO Guoshun ZHAO +2 位作者 Mengya YANG Susheng CHEN Kai XIAO 《Agricultural Biotechnology》 CAS 2018年第3期19-23,共5页
In this study,effects of nitrogen( N) amount applied on photosynthesis behaviors of the summer millet in North China was investigated. Photosynthetic rates( Pn),chlorophyll contents( Chl),photosynthetic active d... In this study,effects of nitrogen( N) amount applied on photosynthesis behaviors of the summer millet in North China was investigated. Photosynthetic rates( Pn),chlorophyll contents( Chl),photosynthetic active duration( PAD),and chlorophyll relative steady phase( RSP) in flag and the upper third leaves were assessed in cultivars of Baogu 19,Jigu 19,9050,and 60 D under three N treatments [i. e.,0( control),75,and 150 kg/hm2]. Results indicated that the photosynthesis parameters were drastically regulated by external N levels,all of them showing elevation along with the increased N input in both assayed leaves.Among the cultivars examined,behaviors of the photosynthetic parameters were much better in Baogu 19 and worse in 60 D. The plant yields in the cultivars under various N treatments were shown to be in consistent with the behavior of the photosynthesis parameters. Correlation analysis revealed that plant yield is positively correlated with Pn and Chl and significantly positively correlated with PAD and RSP,suggesting that longer effective photosynthetic duration of leaves impacts largely on plant biomass production and the yield formation potential. Our investigation indicates that suitable external N applied can increase the yield of summer millet associating with the improvement of photosynthesis behaviors in upper leaves that contribute to plant biomass at the late growth stage. Baogu 19 exhibited higher plant yield together with improved photosynthetic parameters in upper leaves,suggesting its potential as an elite cultivar in planting in the summer season of North China. 展开更多
关键词 Millet (Setaria italica L. Summer-sown eultivar n application level Photosynthesis parameter Plant productivity
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Analysis on a Set of 12-parameter Rectangular Plate Element with High Accuracy
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作者 SHI Dong-yang WANG Cai-xia 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第2期159-165,共7页
It is proved that the so-called a set of 12-parameter rectangular plate elements with high accuracy constructed by using double set parameter method and undetermined method are, in fact, the same one; the real shape f... It is proved that the so-called a set of 12-parameter rectangular plate elements with high accuracy constructed by using double set parameter method and undetermined method are, in fact, the same one; the real shape function space is nothing but the Adini's element's, which has nothing to do with the other high degree terms and leads to a new method for constructing the high accuracy plate elements. This fact has never been seen for other conventional and unconventional, conforming and nonconforming rectangular plate elements, such as Quasi-conforming elements, generalized conforming elements and other double set parameter finite elements. Moreover, such kind of rectangular elements can not be constructed by the conventional finite element methods. 展开更多
关键词 double set parameter element high accuracy Adini's shape function space geometric symmetry new method
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Study on the Diffraction Patterns of α"-Fe_(16)N_2 with Jack-1 and Jack-2 Structural Parameters
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作者 Zhiquan LIU and Douxing LI (Laboratory of Atomic Imaging of Solids, Institute of Metal Research, CAS, Shenyang 110015, China) Xiaolei XU, Liang WANG and Zukun HEI (Institute of Materials and Technology, Dalian Maritime University, Dalian 116026, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第4期362-366,共5页
Two body centered tetragonal (bet) crystal structures of α'-Fe_(16)N_2 with x=0.25, z=0.3125 (Jack-1) and x=0.222, z=0.306 (Jack-2) respectively, were analyzed theoretically with EMS software package. The simulat... Two body centered tetragonal (bet) crystal structures of α'-Fe_(16)N_2 with x=0.25, z=0.3125 (Jack-1) and x=0.222, z=0.306 (Jack-2) respectively, were analyzed theoretically with EMS software package. The simulation of diffraction patterns indicates that both diffraction patterns of the same axis in these two structures obey bcc extinction rule. The conclusion is also obtained from the analyses of the diffracted waves. α'-Fe_(16)N_2 precipitates in the diffusion layer of ion-nitrided α-iron have been studied with transmission electron microscope (TEM). We have distinctly observed the electron diffraction patterns of α'-Fe_(16)N_2 in [100], [111], [110], [011], [210], [021], [311], [113], [331] and [133] zone axes with perfect symmetry, which indicate the parallel orientation relationship with α matrix:<001>α'//<001>α'// {100}.α'// {100}tα. The analyses of diffraction patterns, which obey bcc extinction rule, verify the bct structure of α'-Fe_(16)N_2 discovered by X-ray diffraction. 展开更多
关键词 Study on the Diffraction Patterns of JACK n2 with Jack-1 and Jack-2 Structural parameters FE
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EQUILIBRIUM MODELS AND PARAMETERS OPTIMIZATION FOR EXTRACTION PROCESS OF BISMUTH AND ANTIMONY WITH N1923
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作者 Han, Wenli Chui,Bingyi(Department of Chemical Engineering of Tsinghua Unirersity,Beijing 100084) 《中国有色金属学会会刊:英文版》 CSCD 1994年第2期33-36,共4页
EQUILIBRIUMMODELSANDPARAMETERSOPTIMIZATIONFOREXTRACTIONPROCESSOFBISMUTHANDANTIMONYWITHN1923EQUILIBRIUMMODELS... EQUILIBRIUMMODELSANDPARAMETERSOPTIMIZATIONFOREXTRACTIONPROCESSOFBISMUTHANDANTIMONYWITHN1923EQUILIBRIUMMODELSANDPARAMETERSOPTI... 展开更多
关键词 solvent EXTRACTIOn n1923 BISMUTH and AnTIMOnY copper electrolyte equilibri-um model parameterS OPTIMIZATIOn
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Hausdorff dimension of set generated by exceptional oscillations of a class of N-parameter Ganssian processes
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作者 林正炎 程宗毛 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第2期237-245,共9页
A class of N-parameter Gaussian processes are introduced, which are more general than the N-parameter Wiener process. The definition of the set generated by exceptional oscillations of a class of these processes is gi... A class of N-parameter Gaussian processes are introduced, which are more general than the N-parameter Wiener process. The definition of the set generated by exceptional oscillations of a class of these processes is given, and then the Hausdorff dimension of this set is defined. The Hausdorff dimensions of these processes are studied and an exact representative for them is given, which is similar to that for the two-parameter Wiener process by Zacharie (2001). Moreover, the time set considered is a hyperrectangle which is more general than a hyper-scluare used by Zacharie (2001). For this more general case, a Fernique-type inequality is established and then using this inequality and the Slepian lemma, a Levy's continuity modulus theorem is shown. Independence of increments is required for showing the representative of the Hausdorff dimension by Zacharie (2001). This property is absent for the processes introduced here, so we have to find a different way. 展开更多
关键词 n-parameter Gaussian process modulus of continuityl Hausdorff dimension
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On a Pair of Geometric Parameters of Orlicz Norm
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作者 严亚强 《Northeastern Mathematical Journal》 CSCD 2001年第3期347-352,共6页
For the geometric parameters Q and q of Orlicz norm, we prove where This result improves the traditional estimations of Chen S. T., Rao, M. M. and Wu C.X.
关键词 Orlicz space n-FUnCTIOn geometric parameter
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Spectrometric Measurement of Plasma Parameters Utilizing the Target Ambient Gas O I &N I Atomic Lines in LIBS Experiment
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作者 Ashraf M. El Sherbini Abdel Aziz Saad Al Amer +1 位作者 Ahmed T. Hassan Tharwat M. El Sherbini 《Optics and Photonics Journal》 2012年第4期286-293,共8页
In this article, we shall report the results of the spectroscopic measurements of the plasma parameters utilizing the spectral lines emitted from the air atoms surrounding plasma (O I line at 777.19 nm and N I at 746.... In this article, we shall report the results of the spectroscopic measurements of the plasma parameters utilizing the spectral lines emitted from the air atoms surrounding plasma (O I line at 777.19 nm and N I at 746.83 nm). The plasma was created via irradiation of plane solid aluminum target in open air by a high peak power Nd: YAG laser pulses at fundamental wavelength of 1064 nm. The emission spectra were recorded using Echelle type spectrograph in conjunction with a time gated ICCD camera at different delay time from 1 to 5 μs and at a fixed gate time of 1 μs. The plasma electron density was measured utilizing the Stark broadening of the N I and O I lines and then compared to the reference density as deduced from the optically thin Hα-line at 656.27 nm appeared in the same emission spectra. The results show that under our experimental conditions the air lines are subjected to moderate absorption. The plasma electron temperature was measured utilizing the relative spectral intensity of the air (O I to N I) lines after correcting their spectral radiance against absorption. The standard temperature was measured utilizing the Al II ionic lines. A comparison to the reference temperatures shows a very close agreement after correcting the emission spectral radiance of the air lines against self absorption, which emphasizes the importance of correction process. 展开更多
关键词 LIBS Self Absorption O I-n I LInES Plasma parameters
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Influence of Climatic Parameters on Soybean Subjected to Low Nitrogen Application Rates in Southern Guinea Savanna of Oyo State, Nigeria
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作者 Olukayode Stephen Oyatokun Kolapo Olatunji Oluwasemire Gideon Olajire Adeoye 《Agricultural Sciences》 2021年第5期575-583,共9页
The variability in weather patterns consequent upon climate change constitutes a critical factor influencing soil N availability and the performance of crops. This paper aimed at evaluating the effects of climatic fac... The variability in weather patterns consequent upon climate change constitutes a critical factor influencing soil N availability and the performance of crops. This paper aimed at evaluating the effects of climatic factors on soybean subjected to low N rates under rain-fed situation in the southern Guinea agro-ecology of Oyo State, Nigeria. A 2-year field experiment involving two soybean varieties (TGx1485-1D and TGx1448-2E) and five low rates of N fertilizer application (0, 5, 15, 25, 35 kg/ha) using Urea applied by banding 7 days after planting was arranged in a 5 × 2 split-plot with three replications. N rates constitute the main plot while variety constitutes the sub-plot. Parameters measured include dry shoot weight, shoot N accumulation, and grain yield. Data were subjected to GENSTAT statistical package for analysis, and means separated with Duncan Multiple Range Test (DMRT) at 5% level of probability. Climatic parameters of rainfall, temperature, and potential evapotranspiration data were collected from the surface observatory of the National meteorological agency (NIMET) and subjected to Excel package for computation and graphics. The dry shoot weight increases as N rate increases up to 25 kg/ha, but declines at 35 kg/ha application rate, however, TGx1448-2E produced a higher dry shoot weight (2.9 t/ha) than TGx1485-1D (2.8 t/ha). Low N rates had no significant effects on shoot N accumulation and there was no significant difference in varietal response. Low N rate did not affect grain yield, but the TGx1448-2E had a greater yield of 1.5 t/ha than TGx1485-1D (1.30 t/ha). Annual rainfall amounts were 935.5 mm and1475.8 mm in 2009 and 2010 respectively. Potential evapotranspiration (PET) values were 1676.5 mm and 1676.8 mm in 2009 and 2010 respectively. Temperature values range from 24<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&#730;</span></span></span>C to 29.8<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&#730;</span></span></span>C in both years and the mean monthly temperature for 2009 was 26.5<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&#730;</span></span></span>C and 27.1<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&#730;</span></span></span>C for 2010. The application of N fertilizer to soybean requires appropriate timing for effective use. Climatic parameters such as rainfall, temperature, and evapotranspiration have dire consideration for fertilizer use and efficiency. 展开更多
关键词 Low n-Rate Soybean Variety Climatic parameters Dry Shoot Weight Grain Yield
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Schottky Barrier Parameters of Pd/Ti Contacts on N-Type InP Revealed from I-V-T And C-V-T Measurements
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作者 D. Subba Reddy M. Bhaskar Reddy +1 位作者 N. Nanda Kumar Reddy V. Rajagopal Reddy 《Journal of Modern Physics》 2011年第3期113-123,共11页
We report on the current-voltage (I-V) and capacitance-voltage (C-V) characteristics of the Pd/Ti/n-InP Schottky barrier diodes (SBDs) in the temperature range 160-400 K in steps of 40 K. The barrier heights and ideal... We report on the current-voltage (I-V) and capacitance-voltage (C-V) characteristics of the Pd/Ti/n-InP Schottky barrier diodes (SBDs) in the temperature range 160-400 K in steps of 40 K. The barrier heights and ideality factors of Schottky contact are found in the range 0.35 eV (I-V), 0.73 eV (C-V) at 160 K and 0.63 eV (I-V), 0.61 eV (C-V) at 400 K, respectively. It is observed that the zero-bias barrier height decreases and ideality factor n increase with a decrease in temperature, this behaviour is attributed to barrier inhomogeneities by assuming Gaussian distribution at the interface. The calculated value of series resistance (Rs) from the forward I-V characteristics is decreased with an increase in temperature. The homogeneous barrier height value of approximately 0.71 eV for the Pd/Ti Schottky diode has been obtained from the linear relationship between the temperature-dependent experimentally effective barrier heights and ideality factors. The zero-bias barrier height ( ) versus 1/2kT plot has been drawn to obtain evidence of a Gaussian distribution of the barrier heights and values of = 0.80 eV and = 114 mV for the mean barrier height and standard deviation have been obtained from the plot, respectively. The modified Richardson ln(I0/T2)- ( ) versus 1000/T plot has a good linearity over the investigated temperature range and gives the mean barrier height ( ) and Richardson constant (A*) values as 0.796 eV and 6.16 Acm-2K-2 respectively. The discrepancy between Schottky barrier heights obtained from I-V and C-V measurements is also interpreted. 展开更多
关键词 SCHOTTKY Barrier parameters I-V-T and C-V-T MEASUREMEnTS Pd/Ti SCHOTTKY COnTACTS n-Type InP Gaussian Distribution
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