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Spatio-temporal Variation Characteristics of Extreme Climate Events and Their Teleconnections to Large-scale Ocean-atmospheric Circulation Patterns in Huaihe River Basin,China During 1959–2019
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作者 YAO Tian ZHAO Qiang +6 位作者 WU Chuanhao HU Xiaonong XIA Chuan'an WANG Xuan SANG Guoqiang LIU Jian WANG Haijun 《Chinese Geographical Science》 SCIE CSCD 2024年第1期118-134,共17页
Huaihe River Basin(HRB) is located in China’s north-south climatic transition zone,which is very sensitive to global climate change.Based on the daily maximum temperature,minimum temperature,and precipitation data of... Huaihe River Basin(HRB) is located in China’s north-south climatic transition zone,which is very sensitive to global climate change.Based on the daily maximum temperature,minimum temperature,and precipitation data of 40 meteorological stations and nine monthly large-scale ocean-atmospheric circulation indices data during 1959–2019,we present an assessment of the spatial and temporal variations of extreme temperature and precipitation events in the HRB using nine extreme climate indices,and analyze the teleconnection relationship between extreme climate indices and large-scale ocean-atmospheric circulation indices.The results show that warm extreme indices show a significant(P < 0.05) increasing trend,while cold extreme indices(except for cold spell duration) and diurnal temperature range(DTR) show a significant decreasing trend.Furthermore,all extreme temperature indices show significant mutations during 1959-2019.Spatially,a stronger warming trend occurs in eastern HRB than western HRB,while maximum 5-d precipitation(Rx5day) and rainstorm days(R25) show an increasing trend in the southern,central,and northwestern regions of HRB.Arctic oscillation(AO),Atlantic multidecadal oscillation(AMO),and East Atlantic/Western Russia(EA/WR) have a stronger correlation with extreme climate indices compared to other circulation indices.AO and AMO(EA/WR) exhibit a significant(P < 0.05) negative(positive)correlation with frost days and diurnal temperature range.Extreme warm events are strongly correlated with the variability of AMO and EA/WR in most parts of HRB,while extreme cold events are closely related to the variability of AO and AMO in eastern HRB.In contrast,AMO,AO,and EA/WR show limited impacts on extreme precipitation events in most parts of HRB. 展开更多
关键词 extreme climate indices sen’s slope variation mutation test atmospheric circulation indices Pearson’s correlation analysis Huaihe River Basin(HRB) China
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VECTORIAL EKELAND'S VARIATIONAL PRINCIPLE WITH A W-DISTANCE AND ITS EQUIVALENT THEOREMS 被引量:8
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作者 丘京辉 李博 贺飞 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2221-2236,共16页
By using the properties of w-distances and Gerstewitz's functions, we first give a vectorial Takahashi's nonconvex minimization theorem with a w-distance. From this, we deduce a general vectorial Ekeland's variatio... By using the properties of w-distances and Gerstewitz's functions, we first give a vectorial Takahashi's nonconvex minimization theorem with a w-distance. From this, we deduce a general vectorial Ekeland's variational principle, where the objective function is from a complete metric space into a pre-ordered topological vector space and the perturbation contains a w-distance and a non-decreasing function of the objective function value. From the general vectorial variational principle, we deduce a vectorial Caristfs fixed point theorem with a w-distance. Finally we show that the above three theorems are equivalent to each other. The related known results are generalized and improved. In particular, some conditions in the theorems of [Y. Araya, Ekeland's variational principle and its equivalent theorems in vector optimization, J. Math. Anal. Appl. 346(2008), 9-16] are weakened or even completely relieved. 展开更多
关键词 Takahashi's minimization theorem Ekeland's variational principle Caristi'sfixed point theorem Gerstewitz's function w-distance
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Seasonal variations in the energy budget of Elliot's pheasant (Syrmaticus ellioti) in cage 被引量:6
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作者 Ying LUO Tai-Lin YU +3 位作者 Cheng-Ming HUANG Tong ZHAO Han-Hua LI Chang-Jian LI 《Zoological Research》 CAS CSCD 北大核心 2013年第1期I0024-I0030,共7页
This study aimed to discuss the energy budget of Elliot's pheasant Syrmaticus ellioti in different seasons, with life and health, good growth and normal digestion of Elliot's pheasant as the tested objects, Th... This study aimed to discuss the energy budget of Elliot's pheasant Syrmaticus ellioti in different seasons, with life and health, good growth and normal digestion of Elliot's pheasant as the tested objects, The energy budget of Elliot's pheasant was measured by daily collection of the trial pheasants' excrement in the biological garden of Guangxi Normal University from March 2011 to February 2012. The results showed that the gross energy consumption, metabolic energy and excrement energy varied by season, increasing as temperature decreased. There was significant difference in gross energy consumption, metabolic energy, excrement energy between adults and nonages. There was also a trend that food digestibility of pheasants increases as temperature increases. In the same season, the food digestibility of adults was better than that of nonages. Throughout spring, summer, autumn and winter, the metabolic energy of 4-year adults were 305.77±13.40 kJ/d, 263.67±11.89 kJ/d, 357.23±25.49 kJ/d and 403.12±24.91 kJ/d, respectively, and the nonages were 284.86±17.22 kJ/d, 284. 66±15.16 kJ/d, 402. 26±31.46 kJ/d and 420. 30±31.98 kJ/d, respectively. The minimum metabolic energies were 247.65±21.81 g, 265.86±26.53 g, respectively for each group, detected between 4-year adults and 1-year nonages. Further study is needed to determine whether 29.6 C is the optimal temperature for the Elliot's pheasant. 展开更多
关键词 Elliot's pheasants Energy budget seasonal variations
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Variational Calculus With Conformable Fractional Derivatives 被引量:4
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作者 Matheus J.Lazo Delfim F.M.Torres 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2017年第2期340-352,共13页
Invariant conditions for conformable fractional problems of the calculus of variations under the presence of external forces in the dynamics are studied. Depending on the type of transformations considered, different ... Invariant conditions for conformable fractional problems of the calculus of variations under the presence of external forces in the dynamics are studied. Depending on the type of transformations considered, different necessary conditions of invariance are obtained. As particular cases, we prove fractional versions of Noether's symmetry theorem. Invariant conditions for fractional optimal control problems, using the Hamiltonian formalism, are also investigated. As an example of potential application in Physics, we show that with conformable derivatives it is possible to formulate an Action Principle for particles under frictional forces that is far simpler than the one obtained with classical fractional derivatives. 展开更多
关键词 Conformable fractional derivative fractional calculus of variations fractional optimal control invariant variational conditions Noether’s theorem
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Recent Advances on Herglotz’s Generalized Variational Principle of Nonconservative Dynamics 被引量:5
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作者 ZHANG Yi 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第1期13-26,共14页
This paper summarized the recent development on Herglotz’s generalized variational principle and its symmetries and conserved quantities for nonconservative dynamical systems.Taking Lagrangian mechanics,Hamiltonian m... This paper summarized the recent development on Herglotz’s generalized variational principle and its symmetries and conserved quantities for nonconservative dynamical systems.Taking Lagrangian mechanics,Hamiltonian mechanics and Birkhoffian mechanics as three research frames,we introduce Herglotz’s generalized variational principle,dynamical equations of Herglotz type,Noether symmetry and conserved quantities,and their generalization to time-delay dynamics,fractional dynamics and time-scale dynamics,and put forward some problems as suggestions for future research. 展开更多
关键词 nonconservative dynamics Herglotz’s generalized variational principle Lagrangian mechanics Hamil-tonian mechanics Birkhoffian mechanics
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Variations in wood tratis in micro and macro propagated plantation woods of Populus deltoides Bartr. ex Marsh 被引量:5
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作者 Pramod K. Pande Ramesh C. Dhiman 《Advances in Bioscience and Biotechnology》 2010年第4期263-275,共13页
The paper presents a comparison between intra-ramet, intra-clonal and inter-clonal variations in girth at breast height (gbh), fiber length, fiber diameter, wall thickness, vessel element length, vessel element diamet... The paper presents a comparison between intra-ramet, intra-clonal and inter-clonal variations in girth at breast height (gbh), fiber length, fiber diameter, wall thickness, vessel element length, vessel element diameter and specific gravity in the ramets of L34, G3 and S7C15 clones of Populus deltoides at the age of 6 years old produced from planting material grown by macro- and micro-propagation techniques. Variance ratio (F) test indicated that intra-ramet variations were non-significant for all the characters except specific gravity for height in L34 for macro and specific gravity and vessel element diameter for radial locations for micro, and fiber length for G3 (micro) for height, and specific gravity for radial location and fiber length for height for S7C15 clone for both the techniques. The clone L34 showed the significantly higher girth followed by G3 and S7C15. The variations were significant for girth, vessel element length and specific gravity between the wood produced from planting stocks grown by two techniques. Intra-clonal variations were significant for fiber length, fiber diameter and vessel element length. In general wood element’s dimensions and specific gravity increased from bottom to top and pith to periphery radial locations. G3 clone was different from the L34 and S7C15 clone for the wood traits. The three different clones of Populus deltoides showed variability in wood anatomical properties and specific gravity in the woods grown from macro- and micro-propagated planting stock. So, the plantation raised by two techniques could not produce similar type of wood even from the same clone. G3 clone was the exception as it did not show variation in wood traits for two techniques. Intra-clonal variations in all the three clones of P. deltoides indicated that wood traits were not stable within the population of same clone grown by either method. 展开更多
关键词 Axial variation Radial variation VEssEL Element’s Dimension Fiber Dimensions specific GRAVITY
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SINGLE PROJECTION ALGORITHM FOR VARIATIONAL INEQUALITIES IN BANACH SPACES WITH APPLICATION TO CONTACT PROBLEM 被引量:3
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作者 Yekini SHEHU 《Acta Mathematica Scientia》 SCIE CSCD 2020年第4期1045-1063,共19页
We study the single projection algorithm of Tseng for solving a variational inequality problem in a 2-uniformly convex Banach space.The underline cost function of the variational inequality is assumed to be monotone a... We study the single projection algorithm of Tseng for solving a variational inequality problem in a 2-uniformly convex Banach space.The underline cost function of the variational inequality is assumed to be monotone and Lipschitz continuous.A weak convergence result is obtained under reasonable assumptions on the variable step-sizes.We also give the strong convergence result for when the underline cost function is strongly monotone and Lipchitz continuous.For this strong convergence case,the proposed method does not require prior knowledge of the modulus of strong monotonicity and the Lipschitz constant of the cost function as input parameters,rather,the variable step-sizes are diminishing and non-summable.The asymptotic estimate of the convergence rate for the strong convergence case is also given.For completeness,we give another strong convergence result using the idea of Halpern iteration when the cost function is monotone and Lipschitz continuous and the variable step-sizes are bounded by the inverse of the Lipschitz constant of the cost function.Finally,we give an example of a contact problem where our proposed method can be applied. 展开更多
关键词 variational inequality 2-uniformly convex Banach space Tseng’s algorithm strong convergence rate of convergence
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Interactions of chemical carcinogens and genetic variation in hepatocellular carcinoma 被引量:1
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作者 Yu-Jing Zhang 《World Journal of Hepatology》 CAS 2010年第3期94-102,共9页
In the etiology of hepatocellular carcinoma (HCC), in addition to hepatitis B virus and hepatitis C virus infections, chemical carcinogens also play important roles. For example, aflatoxin B 1 (AFB 1 ) epoxide reacts ... In the etiology of hepatocellular carcinoma (HCC), in addition to hepatitis B virus and hepatitis C virus infections, chemical carcinogens also play important roles. For example, aflatoxin B 1 (AFB 1 ) epoxide reacts with guanine in DNA and can lead to genetic changes. In HCC, the tumor suppressor gene p53 codon 249 mutation is associated with AFB 1 exposure and mutations in the K -ras oncogene are related to vinyl chloride exposure. Numerous genetic alterations accumulate during the process of hepatocarcinogenesis. Chemical carcinogen DNA-adduct formation is the basis for these genetic changes and also a molecular marker which reflects exposure level and biological effects. Metabolism of chemical carcinogens, including their activation and detoxification, also plays a key role in chemical hepatocarcinogenesis. Cytochrome p450 enzymes, N -acetyltransferases and glutathione S -transferases are involved in activating and detoxifying chemical carcinogens. These enzymes are polymorphic and genetic variation influences biological response to chemical carcinogens. This genetic variation has been postulated to influence the variability in risk for HCC observed both within and across populations. Ongoing studies seek to fully understand the mechanisms by which genetic variation in response to chemical carcinogens impacts on HCC risk. 展开更多
关键词 Hepatocellular carcinoma Chemical CARCINOGENs AFLATOXIN B 1 POLYCYCLIC aromatic hydrocarbons 4-aminobiphenyl HEPATITIs B VIRUs HEPATITIs C VIRUs Glutathione s -transferase Cytochrome p450 enzymes Genetic variation
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Regional variation of pediatric inflammatory bowel disease in Saudi Arabia: Results from a multicenter study 被引量:1
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作者 Mohammad I El Mouzan Mohammed H AlEdreesi +3 位作者 Mohammed Y Hasosah Abdulrahman A Al-Hussaini Ahmad A Al Sarkhy Asaad A Assiri 《World Journal of Gastroenterology》 SCIE CAS 2020年第4期416-423,共8页
BACKGROUND Incidence and severity variations of inflammatory bowel disease(IBD)have been reported from Western populations between continents and regions of the same countries.However,no data were available from other... BACKGROUND Incidence and severity variations of inflammatory bowel disease(IBD)have been reported from Western populations between continents and regions of the same countries.However,no data were available from other countries.AIM To investigate the regional differences in the IBD profiles of pediatric patients from the Kingdom of Saudi Arabia.METHODS Data from a national multicenter IBD study were used.The incidence,time trend,and clinical presentation of Crohn’s disease(CD)and ulcerative colitis(UC)in the Central region(CR),Western region(WR),and Eastern region(ER)were analyzed and compared.Statistical analysis included Poisson regression analysis for incidence variation and Chi-square test for demographic and clinical parameters.A P<0.05 was considered significant.RESULTS The prevalence of positive family history was lower in children with CD from the ER than the CR or the WR.Consanguinity rate was higher in children with CD and UC from the CR and the ER,respectively.The incidences and time trends of CD and UC were not significantly different between regions.In the ER,a significantly higher percentage of children with CD presented with abdominal pain(P<0.001),blood in stools(P=0.048),stricturing or penetrating disease(P=0.029),higher erythrocyte sedimentation rate(P<0.001),higher C-reactive protein(P<0.001),higher anemia(P=0.017),and lower albumin level(P=0.014).For children with UC from the ER,a significantly higher percentage presented with anemia(P=0.006)and a lower percentage with pancolitis(P<0.001).CONCLUSION The most important finding is the identification of significantly more severe presentation of CD in the ER of the Kingdom of Saudi Arabia.Prospective studies are needed to explain such variations. 展开更多
关键词 Crohn’s disease Ulcerative colitis EPIDEMIOLOGY CHILDREN Regional variation
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STRONG CONVERGENCE OF AN INERTIAL EXTRAGRADIENT METHOD WITH AN ADAPTIVE NONDECREASING STEP SIZE FOR SOLVING VARIATIONAL INEQUALITIES 被引量:1
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作者 Nguyen Xuan LINH Duong Viet THONG +2 位作者 Prasit CHOLAMJIAK Pham Anh TUAN Luong Van LONG 《Acta Mathematica Scientia》 SCIE CSCD 2022年第2期795-812,共18页
In this work,we investigate a classical pseudomonotone and Lipschitz continuous variational inequality in the setting of Hilbert space,and present a projection-type approximation method for solving this problem.Our me... In this work,we investigate a classical pseudomonotone and Lipschitz continuous variational inequality in the setting of Hilbert space,and present a projection-type approximation method for solving this problem.Our method requires only to compute one projection onto the feasible set per iteration and without any linesearch procedure or additional projections as well as does not need to the prior knowledge of the Lipschitz constant and the sequentially weakly continuity of the variational inequality mapping.A strong convergence is established for the proposed method to a solution of a variational inequality problem under certain mild assumptions.Finally,we give some numerical experiments illustrating the performance of the proposed method for variational inequality problems. 展开更多
关键词 Inertial method Tseng’s extragradient viscosity method variational inequality problem pseudomonotone mapping strong convergence
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INFINITELY MANY SOLUTIONS FOR ELLIPTIC SYSTEMS WITH STRONGLY INDEFINITE VARIATIONAL STRUCTURE 被引量:1
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作者 刘朝霞 《Acta Mathematica Scientia》 SCIE CSCD 2010年第1期55-64,共10页
Based on the multiplicity results of Benci and Fortunato [4], we consider some elliptic systems with strongly indefinite quadratic part, and establish the existence of infinitely many nontrivial solutions in a suitabl... Based on the multiplicity results of Benci and Fortunato [4], we consider some elliptic systems with strongly indefinite quadratic part, and establish the existence of infinitely many nontrivial solutions in a suitable family of products of fractional Sobolev spaces. 展开更多
关键词 semilinear elliptic systems variational functional (P.s.)c sequence criticalpoint
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Investigation on variations of apparent stress in the region in and around the rupture volume preceding the occurrence of the 2021 Alaska MW8.2 earthquake 被引量:1
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作者 Xuezhong Chen Yane Li Lijuan Chen 《Earthquake Science》 2022年第3期147-160,共14页
On July 29, 2021, a large earthquake of MW8.2 occurred south of the Alaska Peninsula. To investigate the spatial-temporal changes of crustal stress in the earthquake-stricken area before this event, we selected 159 ea... On July 29, 2021, a large earthquake of MW8.2 occurred south of the Alaska Peninsula. To investigate the spatial-temporal changes of crustal stress in the earthquake-stricken area before this event, we selected 159 earthquakes of 4.7 ≤ MW ≤ 6.9 that occurred in the epicentral region and its surroundings between January 1980 and June 2021 to study the temporal variation and spatial distribution of their apparent stress. In addition, we analyzed the correlation between seismic activities and Earth’s rotation and explored the seismogenic process of this earthquake. The crustal stress rose from January 2008 to December 2016. This period was followed by a sub-instability stage from January 2017 until the occurrence of the MW8.2 earthquake. The average rate of apparent stress change in the first five years of the stress increase period was roughly 2.3 times that in the last four years. The lateral distribution of the apparent stress shows that the areas with apparent stress greater than 1.0 MPa exhibited an expanding trend during the seismogenic process. The maximum apparent stress was located at the earthquake epicenter during the last four years. The distribution of the apparent stress in the E-W vertical cross section revealed that an apparent stress gap formed around the hypocenter during the first five years of the stress increase period, surrounded by areas of relatively high apparent stress. After the Alaska earthquake, most parts of this gap were filled in by aftershocks. The seismic activities during the sub-instability stage exhibited a significant correlation with Earth’s rotation. 展开更多
关键词 MW8.2 earthquake in Alaska apparent stress variation characteristics Earth’s rotation correlation.
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Diurnal variations of carbon dioxide,methane,and nitrous oxide fluxes from invasive Spartina alterniflora dominated coastal wetland in northern Jiangsu Province 被引量:2
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作者 XU Xinwanghao FU Guanghe +2 位作者 ZOU Xinqing GE Chendong ZHAO Yifei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第4期105-113,共9页
The invasions of the alien species such as Spartina alterniflora along the northern Jiangsu coastlines have posed a threat to biodiversity and the ecosystem function.Yet,limited attention has been given to their poten... The invasions of the alien species such as Spartina alterniflora along the northern Jiangsu coastlines have posed a threat to biodiversity and the ecosystem function.Yet,limited attention has been given to their potential influence on greenhouse gas(GHG) emissions,including the diurnal variations of GHG fluxes that are fundamental in estimating the carbon and nitrogen budget.In this study,we examined the diurnal variation in fluxes of carbon dioxide(CO_2),methane(CH_4),and nitrous oxide(N2O) from a S.alterniflora intertidal flat in June,October,and December of 2013 and April of 2014 representing the summer,autumn,winter,and spring seasons,respectively.We found that the average CH_4 fluxes on the diurnal scale were positive during the growing season while negative otherwise.The tidal flat of S.alterniflora acted as a source of CH_4 in summer(June) and a combination of source and sink in other seasons.We observed higher diurnal variations in the CO_2 and N_2O fluxes during the growing season(1 536.5 mg CO_2 m^(–2) h^(–1) and 25.6 μg N_2O m^(–2) h^(–1)) compared with those measured in the non-growing season(379.1 mg CO_2 m^(–2) h^(–1) and 16.5 μg N_2O m^(–2) h^(–1)).The mean fluxes of CH_4 were higher at night than that in the daytime during all the seasons but October.The diurnal variation in the fluxes of CO_2 in June and N_2O in December fluctuated more than that in October and April.However,two peak curves in October and April were observed for the diurnal changes in CO_2 and N_2O fluxes(prominent peaks were found in the morning of October and in the afternoon of April,respectively).The highest diurnal variation in the N_2O fluxes took place at 15:00(86.4 μg N_2O m^(–2) h^(–1)) in June with an unimodal distribution.Water logging in October increased the emission of CO_2(especially at nighttime),yet decreased N_2O and CH_4 emissions to a different degree on the daily scale because of the restrained diffusion rates of the gases.The seasonal and diurnal variations of CH_4 and CO_2 fluxes did not correlate to the air and soil temperatures,whereas the seasonal and diurnal variation of the fluxes of N_2O in June exhibited a significant correlation with air temperature.When N_2O and CH_4 fluxes were converted to CO_2-e equivalents,the emissions of N_2O had a remarkable potential to impact the global warming.The mean daily flux(MF) and total daily flux(TDF) were higher in the growing season,nevertheless,the MF and TDF of CO_2 were higher in October and those of CH_4 and N_2O were higher in June.In spite of the difference in the optimal sampling times throughout the observation period,our results obtained have implications for sampling and scaling strategies in estimating the GHG fluxes in coastal saline wetlands. 展开更多
关键词 methane nitrous oxide carbon dioxide diurnal variation s.alterniflora
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The Space of Bounded p(&#183;)-Variation in Wiener’s Sense with Variable Exponent 被引量:1
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作者 Odalis Mejía Nelson Merentes José Luis Sánchez 《Advances in Pure Mathematics》 2015年第11期703-716,共14页
In this paper, we proof some properties of the space of bounded p(·)-variation in Wiener’s sense. We show that a functions is of bounded p(·)-variation in Wiener’s sense with variable exponent if and only ... In this paper, we proof some properties of the space of bounded p(·)-variation in Wiener’s sense. We show that a functions is of bounded p(·)-variation in Wiener’s sense with variable exponent if and only if it is the composition of a bounded nondecreasing functions and h?lderian maps of the variable exponent. We show that the composition operator H, associated with , maps the spaces into itself if and only if h is locally Lipschitz. Also, we prove that if the composition operator generated by maps this space into itself and is uniformly bounded, then the regularization of h is affine in the second variable. 展开更多
关键词 Generalized variation p(·)-variation in Wiener’s sENsE Variable EXPONENT Composition OPERATOR Matkowski’s Condition
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Predicting GM(1,N) Model for the Coefficient of Variation of Hectometer Yarn's Weight 被引量:1
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作者 李晓峰 《Journal of Donghua University(English Edition)》 EI CAS 2010年第3期391-394,共4页
The Coefficient of Variation(CV)of hectometer yarn's weight is one of the guidelines to evaluate its intrinsic quality.In the spinning manufacturing,the control of cotton yarn's weight unevenness is accomplish... The Coefficient of Variation(CV)of hectometer yarn's weight is one of the guidelines to evaluate its intrinsic quality.In the spinning manufacturing,the control of cotton yarn's weight unevenness is accomplished mainly in terms of a spot-check on semi-product and a succedent adjust in process parameters during spinning based on technicians' experience.However,it is theoretically believed among manufacturers that with fixed technical levels and parameters in the spinning process,the quality parameters of assorted cotton have a certain influence on the CV.In order to find out a rule of the influence that assorted cotton has on the CV,a GM(1,N)model,correlated raw cotton's quality parameter with the CV,has firstly been developed according to the modeling theory of grey system,and then been applied in the designing step to predict the CV.It has been approved by practical modeling and validation that the model could fit preferably an accrual CV value,and provide a method of quantitative predicting analysis for textile manufacturers to design cotton yarn's quality. 展开更多
关键词 cotton yarn coefficient of variation(CV) raw cotton's quality GM(1 N) PREDICTION
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Interannual Variation of the Onset of Yunnan’s Rainy Season and Its Relationships with the Arctic Oscillation of the Preceding Winter 被引量:1
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作者 Yan Chen Shichang Guo +2 位作者 Yu Liu Jianhua Ju Juzhang Ren 《Atmospheric and Climate Sciences》 2017年第2期210-222,共13页
Based on an analysis of the circulation in May associated with the interannual variation of the onset of Yunnan’s rainy season, this study examined the rela-tionship between Arctic Oscillation (AO) and the onset timi... Based on an analysis of the circulation in May associated with the interannual variation of the onset of Yunnan’s rainy season, this study examined the rela-tionship between Arctic Oscillation (AO) and the onset timing of the rainy sea-son by using the NCEP/NCAR reanalysis and observational precipitation data for 1961-2010. The results indicated that, on an interannual time scale, intense Asian summer monsoon and an active EU-pattern wave train circulation in its positive phase, associated with a cold cyclonic cell covering the western part of the East Asian subtropical westerly jet (EASWJ), jointly contributed to the onset of the rainy season in May. Otherwise, the onset might be suppressed. The cold cyclonic cell over East Asia likely led to the southward shift and enhancement of EASWJ as well as its secondary circulation around the jet entrance, which could provide a favorable dynamic and thermal condition for rainfalls in Yunnan as was revealed in previous studies on 10 - 30-day time scale. Further examination showed that the preceding wintertime AO played a significant role in the timing of the onset of the rainy season before the mid-1980s’ by mostly modulating the wave-train-like circulation over East Asia in May. During that time period, when the AO index of the previous winter was positive (negative), Yunnan’s rainy season tended to begin earlier (later) than normal. Correspond-ingly, the precipitation in May was also closely linked to wintertime AO. 展开更多
关键词 ONsET of Yunnan’s RAINY sEAsON East Asian sUBTROPICAL WEsTERLY Jet (EAsWJ) Arctic Oscillation (AO) INTERANNUAL variation
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Genetic variation of Leptospira isolated from rats catched in Yogyakarta Indonesia
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作者 Hadi Sumanta Tri Wibawa +2 位作者 Suwarno Hadisusanto Anik Nuryati Hari Kusnanto 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2015年第9期698-701,共4页
Objective: To detect genetic variations among pathogenic Leptospira isolated from rats using 16 S r RNA gen as chronometer. Methods: This is an observational study with cross sectional design. Rats saples were taken i... Objective: To detect genetic variations among pathogenic Leptospira isolated from rats using 16 S r RNA gen as chronometer. Methods: This is an observational study with cross sectional design. Rats saples were taken in Yogyakarta Special Region of Indonesia. Leptospira in the rats was detected by two methods ie. real time PCR(q PCR) by using primers correspond to16 S r RNA gene of Leptospira, and standard PCR by using dif erent set of primer correspond to the 16 S r RNA gene of Leptospira. The standard PCR amplicon then subjected for DNA sequencing. Analysis genetic variation was performed using MEGA 6.2. Software. Results:There were 99 DNA samples from rats included in this study. Detection of Leptospira by using q PCR revealed 25 samples positive for pathogenic Leptospira, while only 6 samples were able to be detected using standard PCR. The new primer set correspond to 16 S r RNA gene was able to detect specii cally pathogenic Leptospira in the rats. Sequencing analysis of 6 PCR amplicons showed that the Leptospira which infect the rats catched in Yogyakarta genetically close related with pathogenic Leptospira which were isolated from human, animal, rodents, and environment. Conclusions: It can be considered that rats are the most important vector and reservoir of Leptospira. 展开更多
关键词 PATHOGENIC LEPTOsPIRA 16s RRNA RATs GENETIC variation
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New way to construct high order Hamiltonian variational integrators
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作者 Minghui FU Kelang LU +1 位作者 Weihua LI S. V. SHESHENIN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2016年第8期1041-1052,共12页
This paper develops a new approach to construct variational integrators. A simplified unconventional Hamilton's variational principle corresponding to initial value problems is proposed, which is convenient for appli... This paper develops a new approach to construct variational integrators. A simplified unconventional Hamilton's variational principle corresponding to initial value problems is proposed, which is convenient for applications. The displacement and mo- mentum are approximated with the same Lagrange interpolation. After the numerical integration and variational operation, the original problems are expressed as algebraic equations with the displacement and momentum at the interpolation points as unknown variables. Some particular variational integrators are derived. An optimal scheme of choosing initial values for the Newton-Raphson method is presented for the nonlinear dynamic system. In addition, specific examples show that the proposed integrators are symplectic when the interpolation point coincides with the numerical integration point, and both are Gaussian quadrature points. Meanwhile, compared with the same order symplectic Runge-Kutta methods, although the accuracy of the two methods is almost the same, the proposed integrators are much simpler and less computationally expensive. 展开更多
关键词 Hamiltonian system variational integrator symplectic algorithm unconventional Hamilton's variational principle nonlinear dynamics
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A NEW ITERATIVE METHOD FOR FINDING COMMON SOLUTIONS OF GENERALIZED EQUILIBRIUM PROBLEM,FIXED POINT PROBLEM OF INFINITE k-STRICT PSEUDO-CONTRACTIVE MAPPINGS,AND QUASI-VARIATIONAL INCLUSION PROBLEM 被引量:5
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作者 刘敏 张石生 《Acta Mathematica Scientia》 SCIE CSCD 2012年第2期499-519,共21页
In this article, we introduce a hybrid iterative scheme for finding a common element of the set of solutions for a generalized equilibrium problems, the set of common fixed point for a family of infinite k-strict pseu... In this article, we introduce a hybrid iterative scheme for finding a common element of the set of solutions for a generalized equilibrium problems, the set of common fixed point for a family of infinite k-strict pseudo-contractive mappings, and the set of solutions of the variational inclusion problem with multi-valued maximal monotone mappings and inverse-strongly monotone mappings in Hilbert space. Under suitable conditions, some strong convergence theorems are proved. Our results extends the recent results in G.L.Acedo and H.K.Xu [2], Zhang, Lee and Chan [8], Wakahashi and Toyoda [9], Takahashi and Takahashi [I0] and S. S. Chang, H. W. Joseph Lee and C. K. Chan [II], S.Takahashi and W.Takahashi [12]. Moreover, the method of proof adopted in this article is different from those of [4] and [12]. 展开更多
关键词 k-strict pseudo-contractive mappings generalized equilibrium problem vis-cosity approximation method variational inclusion problem multi-valuedmaximal monotone mappings s-inverse-strongly monotone mapping
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Seasonal variations in the energy budget of Elliot’s pheasant (Syrmaticus ellioti) in cage
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作者 Ying LUO Tai-Lin YU +3 位作者 Cheng-Ming HUANG Tong ZHAO Han-Hua LI Chang-Jian LI 《Zoological Research》 SCIE CAS CSCD 北大核心 2013年第S01期19-25,共7页
This study aimed to discuss the energy budget of Elliot’s pheasant Syrmaticus ellioti in different seasons,with life and health,good growth and normal digestion of Elliot’s pheasant as the tested objects,The energy ... This study aimed to discuss the energy budget of Elliot’s pheasant Syrmaticus ellioti in different seasons,with life and health,good growth and normal digestion of Elliot’s pheasant as the tested objects,The energy budget of Elliot’s pheasant was measured by daily collection of the trial pheasants’excrement in the biological garden of Guangxi Normal University from March 2011 to February 2012.The results showed that the gross energy consumption,metabolic energy and excrement energy varied by season,increasing as temperature decreased.There was significant difference in gross energy consumption,metabolic energy,excrement energy between adults and nonages.There was also a trend that food digestibility of pheasants increases as temperature increases.In the same season,the food digestibility of adults was better than that of nonages.Throughout spring,summer,autumn and winter,the metabolic energy of 4-year adults were 305.77±13.40 kJ/d,263.67±11.89 kJ/d,357.23±25.49 kJ/d and 403.12±24.91 kJ/d,respectively,and the nonages were 284.86±17.22 kJ/d,284.66±15.16 kJ/d,402.26±31.46 kJ/d and 420.30±31.98 kJ/d,respectively.The minimum metabolic energies were 247.65±21.81 g,265.86±26.53 g,respectively for each group,detected between 4-year adults and 1-year nonages.Further study is needed to determine whether 29.6 C is the optimal temperature for the Elliot’s pheasant. 展开更多
关键词 Elliot’s pheasants Energy budget seasonal variations
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