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论杜威“生长理论”中的终身教育思想 被引量:1
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作者 赵红亚 《继续教育研究》 2005年第4期23-26,共4页
杜威在其1916年出版的《民主主义与教育》一书中指出,教育即生长、教育即生活、教育即经验的不断重组和改造、学校即社会等观点,强调教育时间的连续性,教育空间的广阔性,教育内容的多样性以及教育方法的灵活性。这些正是终身教育思想的... 杜威在其1916年出版的《民主主义与教育》一书中指出,教育即生长、教育即生活、教育即经验的不断重组和改造、学校即社会等观点,强调教育时间的连续性,教育空间的广阔性,教育内容的多样性以及教育方法的灵活性。这些正是终身教育思想的核心理念,所以在西方杜威一直被视为终身教育的教育哲学创始人。 展开更多
关键词 杜威 “生长理论” 终身教育 教育思想 民主主义
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Studies on stand dynamic growth model for larch in Jilin in China 被引量:1
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作者 翁国庆 陈雪峰 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第4期323-326,共4页
The stand growth and yield dynamic models for Larch in Jilin Province were developed based on the forest growth theories with the forest continuous inventory data. The results indicated that the developed models had h... The stand growth and yield dynamic models for Larch in Jilin Province were developed based on the forest growth theories with the forest continuous inventory data. The results indicated that the developed models had high precision, and they could be used for the updating data of inventory of planning and designing and optimal decision of forest management. 展开更多
关键词 Stand Dynamics Growth Prediction Model
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DFT Study of the Effect of Temperature on ZnO Adsorbed on α-AI_2 O_3(0001)Surface
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作者 杨春 余毅 李来才 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第2期137-142,共6页
The adsorption and the growth of ZnO on α-Al2O3(0001) surface at various temperatures were theoretically calculated by using a plane wave pseudopotentials (USP) method based on density functional theory.The avera... The adsorption and the growth of ZnO on α-Al2O3(0001) surface at various temperatures were theoretically calculated by using a plane wave pseudopotentials (USP) method based on density functional theory.The average adsorption energy of ZnO at 400, 600 and 800 ℃ is 4.16±0.08, 4.25±0.11 and 4.05±0.23 eV respectively. Temperature has a remarkable effect on the structure of the surface and the interface of ZnO/α-Al2O3(0001). It is found that the Zn-hexagonal symmetry deflexion does not appear during the adsorption growth of ZnO at 400 ℃, and that the ZnO[10^-10] is parallel with the [10^-10] of the α-Al2O3(0001), which is favorable for forming ZnO film with the Zn-terminated surface. It is observed from simulation that there are two kinds of surface structures in the adsorption of ZnO at 600 ℃: one is the ZnO surface that has the Zn-terminated structure, and whose [10^-10] parallels the [10^-10] of the substrate surface, and the other is the ZnO[10^-10] //sapphire [11-20] with the O-terminated surface. The energy barrier of the phase transition between these two different surface structures is about 1.6 eV, and the latter is more stable. Therefore,the suitable temperature for the thin film growth of ZnO on sapphire is about 600 ℃, and it facilitates the formation of wurtzite structure containing Zn-O-Zn-O-Zn-O double-layers as a growth unit-cell. At 600 ℃, the average bond length of Zn-O is 0.190±0.01 nm, and the ELF value indicates that the bond of (substrate)-O-Zn-O has a distinct covalent character, whereas the (Zn)O-Al (substrate) shows a clear character of ionic bond. However, at a temperature of 800 ℃, the dissociation of Al and O atoms on the surface of the α-Al2O3(0001) leads to a disordered surface and interface structure. Thus, the Zn-hexagonal symmetry structure of the ZnO film is not observed under this condition. 展开更多
关键词 ZNO α-Al2O3(0001) surface ADSORPTION Density functional calculations
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Growth Mechanism of Microcrystalline Silicon Films by Scaling Theory and Monte Carlo Simulation 被引量:1
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作者 訾威 周玉琴 +1 位作者 刘丰珍 朱美芳 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第8期1465-1468,共4页
Hydrogenated microcrystalline silicon (~c-Si:H) films with a high deposition rate of 1.2nm/s were prepared by hot-wire chemical vapor deposition (HWCVD). The growth-front roughening processes of the μc-Si..H fil... Hydrogenated microcrystalline silicon (~c-Si:H) films with a high deposition rate of 1.2nm/s were prepared by hot-wire chemical vapor deposition (HWCVD). The growth-front roughening processes of the μc-Si..H films were investi- gated by atomic force microscopy. According to the scaling theory, the growth exponent β≈0.67, the roughness exponent α≈0.80,and the dynamic exponent 1/z = 0.40 are obtained. These scaling exponents cannot be explained well by the known growth models. An attempt at Monte Carlo simulation has been made to describe the growth process of μc-Si: H film using a particle reemission model where the incident flux distribution,the type and concentration of growth radical, and sticking,reemission,shadowing mechanisms all contributed to the growing morphology. 展开更多
关键词 μc-Si:H growth mechanism scaling theory Monte Carlo simulations reemission process
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Ecological suitability evaluation for urban growth boundary in red soil hilly areas based on fuzzy theory 被引量:6
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作者 焦胜 高青 +5 位作者 魏春雨 刘贝 李晓东 曾光明 袁中兴 梁婕 《Journal of Central South University》 SCIE EI CAS 2012年第5期1364-1369,共6页
The fuzziness exists in spatial distribution of geographic data of land suitability evaluation processes,which makes it difficult to quantify land boundaries by using traditional binary logic-based overlay model.Aimin... The fuzziness exists in spatial distribution of geographic data of land suitability evaluation processes,which makes it difficult to quantify land boundaries by using traditional binary logic-based overlay model.Aiming at this limitation,an ecological suitability evaluation analysis model was presented based on fuzzy theory and a research on urban growth boundary(UGB) of the Great-Hexi Leading District(GHLD) of Changsha was conducted.With the support of GIS,RS and MATLAB,slope,elevation,vegetation,soil productivity,soil permeability,water body and land use are selected as the input of model according to the characteristic properties of soil and terrain in red soil hilly areas.The running result of this model indicates that the ratios of highly suitable land,suitable land,moderately suitable land and unsuitable land in GHLD are 18.75%,10.31%,64.16%,6.78%,respectively.This result accords with spatial structure worked out by Space Development Strategy Planning of GHLD,Based on this result,several suggestions are made to guide UGB developments in future. 展开更多
关键词 land ecological suitability evaluation fuzzy theory urban growth boundary (UGB) GIS MATLAB
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On Growth and Covering Theorem for a Kind of Spiral-like Mappings
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作者 LIU Hao CUI Hong-yu LIU Ai-chao 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第4期488-492,共5页
In this paper, we deduce growth and covering theorem for f(x) by the othermeans where f(x) is strongly spiral-like mapping of type β with order α defined on UnitBall B of complex Banach space and still give gr... In this paper, we deduce growth and covering theorem for f(x) by the othermeans where f(x) is strongly spiral-like mapping of type β with order α defined on UnitBall B of complex Banach space and still give growth upper bound and distortionbound for subordinate mapping. 展开更多
关键词 spiral-like mapping growth and covering theorem subordinate mapping
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Stochastic Resonance in a Bacterium Growth System Subjected to Colored Noises 被引量:1
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作者 ZENG Chun-Hua ZHOU Xiao-Feng TAO Shu-Fen 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第10期615-618,共4页
We present the logistic growth model to study the stochastic resonance (SR) in a bacterium growth system under the simultaneous action of two external multiplicative cross-correlation noises and periodic external fo... We present the logistic growth model to study the stochastic resonance (SR) in a bacterium growth system under the simultaneous action of two external multiplicative cross-correlation noises and periodic external forcing. The expression of the signal-to-noise ratio (SNR) for a bacterium growth system is derived by using the theory of SNR in the adiabatic limit. Based on SNR, we discuss the effects of self-correlation time τ1 and τ2, cross-correlation time 3-3 and cross-correlation strength λ on the SNR. It is found that the self-correlation time τ1 and τ2, and cross-correlation strength λ enhance the SR of the bacterium growth system, while cross-correlation time τ3 weakens the SR of the bacterium growth system. 展开更多
关键词 stochastic resonance bacterium growth system colored noises
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On Growth and Covering Theorem for Strongly Spirallike Mapping of Type β with Order α
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作者 LIU Jie-ming WAN Zhi-jun 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第1期138-142,共5页
In this paper, we deduce growth and covering theorem for f(x) by the other means,where f(x) is strongly spirallike mapping of type β with order α defined on Unit Ball B of complex Banach space, and still give gr... In this paper, we deduce growth and covering theorem for f(x) by the other means,where f(x) is strongly spirallike mapping of type β with order α defined on Unit Ball B of complex Banach space, and still give growth upper bound and distortion upper bound for subordinate mapping. 展开更多
关键词 spirallike mapping growth and covering theorem subordinate mapping
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Electrodeposited PtNi nanoparticles towards oxygen reduction reaction:A study on nucleation and growth mechanism 被引量:1
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作者 Lutian Zhao Yangge Guo +4 位作者 Cehuang Fu Liuxuan Luo Guanghua Wei Shuiyun Shen Junliang Zhang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第11期2068-2077,共10页
In this work,highly monodispersed Pt-Ni alloy nanoparticles were directly deposited on carbon substrate through a facile electrodeposition strategy in the solvent system of N,N-dimethylformamide(DMF).A series of carbo... In this work,highly monodispersed Pt-Ni alloy nanoparticles were directly deposited on carbon substrate through a facile electrodeposition strategy in the solvent system of N,N-dimethylformamide(DMF).A series of carbon supported Pt-Ni alloy electrocatalysts were synthesized under different applied electrode potentials.Among all as-obtained samples,the Pt-Ni/C electrocatalyst deposited at-1.73 V exhibits the optimal specific activity up to 1.850 mA cm^(-2)at 0.9 V vs.RHE,which is 6.85 times higher than that of the commercial Pt/C.Comprehensive physiochemical characterizations and computational evaluations via density functional theory were conducted to unveil the nucleation and growth mechanism of PtNi alloy formation.Compared to the aqueous solution,DMF solvent molecule must not be neglected in avoiding particle agglomeration and synthesis of monodispersed nanoparticles.During the alloy co-deposition process,Ni sites produced through the reduction of Ni(Ⅱ)precursor not only facilitates Pt-Ni alloy crystal nucleation but also in favor of further Pt reduction on the Ni-inserted Pt surface.As for the deposition potential,it adjusts the final particle size.This work provides a hopeful extended Pt-based catalyst layer production strategy for proton exchange membrane fuel cells and a new idea for the nucleation and growth mechanism exploration for electrodeposited Pt alloy. 展开更多
关键词 ELECTRODEPOSITION PtNi alloy nanoparticles Oxygen reduction reaction Nucleation and growth mechanism Density functional theory
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Effect of wave spectrum width on the probability density distribution of wind-wave heights
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作者 刘亚豪 侯一筠 +1 位作者 胡珀 刘泽 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第5期1124-1131,共8页
The probability distribution of wave heights under the assumption of narrowband linear wave theory follows the Rayleigh distribution and the statistical relationships between some characteristic wave heights, derived ... The probability distribution of wave heights under the assumption of narrowband linear wave theory follows the Rayleigh distribution and the statistical relationships between some characteristic wave heights, derived from this distribution, are widely used for the treatment of realistic wind waves. However, the bandwidth of wave frequency influences the probability distribution of wave heights. In this paper, a wave-spectrum-width parameter B was introduced into the JONSWAP spectrum. This facilitated the construction of a wind-wave spectrum and the reconstruction of wind-wave time series for various growth stages, based on which the probability density distributions of the wind-wave heights were studied statistically. The distribution curves deviated slightly from the theoretical Rayleigh distribution with increasing B. The probability that a wave height exceeded a certain value was clearly smaller than the theoretical value for B≥0.3, and the difference between them increased with the threshold value. The relation between the Hs/σ ratio and B was investigated statistically, which revealed that the Hs/σ ratio deviated from 4.005 and declined with B. When B reached 0.698 1, the Hs/σ ratio was 3.825, which is about 95.5% of its original value. This indicates an overestimation in the a potential method for improving the accuracy of the Hs extremely large waves under severe sea states. prediction of Hs from Hs=4.005σ, and provides remote sensing retrieval algorithm, critical for 展开更多
关键词 wave-spectrum width probability distribution of wave heights significant wave height
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Anguilliform Fish Propulsion of Highest Hydrodynamic Efficiency
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作者 William S. Vorus Brandon M. Taravella 《Journal of Marine Science and Application》 2011年第2期163-174,共12页
It is hypothesized that steady anguilliform swimming motion of aquatic animals is purely reactive such that no net vortex wake is left downstream. This is versus carangiform and tunniform swimming of fish, where vorte... It is hypothesized that steady anguilliform swimming motion of aquatic animals is purely reactive such that no net vortex wake is left downstream. This is versus carangiform and tunniform swimming of fish, where vortex streams are shed from tail, fins, and body. But there the animal movements are such to produce partial vortex cancellation downstream in maximizing propulsive efficiency. In anguilliform swimming characteristic of the eel family, it is argued that the swimming motions are configured by the animal such that vortex shedding does not occur at all. However, the propulsive thrust in this case is higher order in the motion amplitude, so that relatively large coils are needed to produce relatively small thrust; the speeds of anguilliform swimmers are less than the carangiform and tunniforrn, which develop first order thrusts via lifting processes. Results of experimentation on live lamprey are compared to theoretical prediction which assumes the no-wake hypothesis. Two-dimensional analysis is first performed to set the concept. This is followed by three-dimensional analysis using slender-body theory. Slender-body theory has been applied by others in studying anguilliform swimming, as it is ideally suited to the geometry of the lamprey and other eel-like animals. The agreement between this new approach based on the hypothesis of wakeless swimming and the experiments is remarkably good in spite of the physical complexities. 展开更多
关键词 HYDRODYNAMICS fish propulsion propulsion efficiency
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A Note of Spirallike Mappings in C^n
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作者 李小申 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第1期52-54, ,共3页
In this paper,the Growth and covering Theorems for a kind of spirallike mapping are given.
关键词 spirallike mappings Growth Theorems normal matrix
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Numerical Simulation of Hot Spot Growth in Detonation with Regard to the Turbulent Mechanism of Energy Transfer
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作者 Yury Vasilyevich Yanilkin Vitaly Grigoryevich Morozov Irina Isorevna Karpenko Olga Nikolaevna Chernyshova 《Journal of Physical Science and Application》 2015年第3期226-237,共12页
The paper presents the results of numerical modeling of hot spot growth process in detonation with account for turbulent mixing. The performed investigation has shown that large-scale HE (High explosives) particles ... The paper presents the results of numerical modeling of hot spot growth process in detonation with account for turbulent mixing. The performed investigation has shown that large-scale HE (High explosives) particles mix up and split down to smaller sizes in the result of shock wave impact, instability development on the HE-EP (Explosion product) interface and vortex flow; at these sizes, due to the developed surface of the HE-EP contact, HE has enough time to get heated (energy transfer from EP), and the decomposition reaction effectively continues. Numerical modeling make the calculation of the hot spot growth rate (about 100-200 m/s) possible. This has proved the hypothesis saying that at mechanical material transport the turbulence in the reaction zone plays an important role and it must be taken into account in the detonation theory. 展开更多
关键词 Hot spot DETONATION turbulent mixing numerical simulation.
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The impact of financial sector development on the economic growth of emerging countries: An empirical study for E-7 countries
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作者 Tulin Atakan Rasim ilker Gokbulut Bengu Vuran 《Journal of Modern Accounting and Auditing》 2010年第12期50-62,共13页
Globalization, financial liberalization, financial integration, financial sector, and economic growth have been significant issues for many researchers. The studies have investigated the effects of the above issues to... Globalization, financial liberalization, financial integration, financial sector, and economic growth have been significant issues for many researchers. The studies have investigated the effects of the above issues to the economic growth of countries both theoretically and empirically. Since there has been conducted an enormous body of work, each of them may be grouped and studied separately. This paper focuses on the impact of financial sector development to economic growth and empirically studies the potential effect on the emerging E-7 countries, consisting of Brazil, China, India, Indonesia, Mexico, the Russian Federation, and Turkey. The study employs panel regression methodology and the data set for modeling Gross Domestic Product (GDP) comprises annual data over 2001-2007, using basic variables which resemble financial sector development, namely market capitalization of listed companies (stock market capitalization), bank capital to asset ratio, stocks traded, total debt service, foreign direct investments, portfolio investments, real interest rates, and claims on private sector. The analysis indicates that the GDP may be modeled using the above stated macroeconomic variables with considerably high explanatory power, except for the real interest rates and bank capital to asset ratios. 展开更多
关键词 finance-growth nexus financial system development economic growth dynamic panel datamethodology
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The Growth of KLN Crystals
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作者 涂朝阳 张雨东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1999年第4期286-289,共4页
The growth temperature curve of the growth system for the potassium lithium niobate (KLN) has been measured and the temperature decrease program has been calculated. KLN crystals with a size up to 30mm 15mm 5 m... The growth temperature curve of the growth system for the potassium lithium niobate (KLN) has been measured and the temperature decrease program has been calculated. KLN crystals with a size up to 30mm 15mm 5 mm have been grown by flux method. The primary factors of the cracking of KLN crystal have been discussed. A blue laser light output has been obtained by optical parametric oscillator pumping.\= 展开更多
关键词 flux method KLN crystal blue doublefrequency laser crystal.
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Sharp Growth Theorems and Coefficient Bounds for Starlike Mappings in Several Complex Variables 被引量:29
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作者 Hidetaka HAMADA Tatsuhiro HONDA 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2008年第4期353-368,共16页
Let B be the unit ball in a complex Banach space. Let S^*k+1(B) be the family of normalized starlike mappings f on B such that z = 0 is a zero of order k + 1 of f(z) - z. The authors obtain sharp growth and cov... Let B be the unit ball in a complex Banach space. Let S^*k+1(B) be the family of normalized starlike mappings f on B such that z = 0 is a zero of order k + 1 of f(z) - z. The authors obtain sharp growth and covering theorems, as well as sharp coefficient bounds for various subsets of S^*k+1(B). 展开更多
关键词 Sharp coefficient bound Sharp covering theorem Sharp growth theorem Starlike mapping Zero of order k
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White light emission from Dy^(3+)-doped LiLuF_4 single crystal grown by Bridgman method 被引量:2
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作者 董艳明 夏海平 +7 位作者 符立 李珊珊 谷雪梅 章践立 王冬杰 张约品 江浩川 陈宝玖 《Optoelectronics Letters》 EI 2014年第4期262-265,共4页
Lithium lutetium fluoride(LiLuF4) single crystals doped with different Dy3+ ion concentrations were grown by Bridgman method. The Judd-Ofelt(J-O) strength parameters(Ω2, Ω4, Ω6) of Dy3+ in LiLuF4 crystal are calcul... Lithium lutetium fluoride(LiLuF4) single crystals doped with different Dy3+ ion concentrations were grown by Bridgman method. The Judd-Ofelt(J-O) strength parameters(Ω2, Ω4, Ω6) of Dy3+ in LiLuF4 crystal are calculated according to the measured absorption spectra and the J-O theory, by which the asymmetry of the Dy3+:LiLuF4 single crystal and the possibility of attaining stimulated emission from 4F9/2 level are analyzed. The capability of the Dy3+:LiLuF4 crystal in generating white light by simultaneous blue and yellow emissions under excitation with ultraviolet light is produced. The effects of excitation wavelength and doping concentration on chromaticity coordinates and photoluminescence intensity are also investigated. Favorable CIE coordinates, x=0.319 3 and y=0.349 3, can be obtained for Dy3+ ion in 2.701% molar doping concentration under excitation of 350 nm. 展开更多
关键词 Crystal growth from melt Judd Ofelt theory
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Solvability of Multi-Point Boundary Value Problem
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作者 张慧星 刘文斌 +1 位作者 张建军 陈太勇 《Journal of Mathematical Research and Exposition》 CSCD 2009年第4期693-699,共7页
This paper deals with the existence of solutions for the problem{(Фp(u′))′=f(t,u,u′),t∈(0,1), u′(0)=0,u(1)=∑i=1^n-2aiu(ηi),where Фp(s)=|s|^p-2s,p〉1.0〈η1〈η2〈…〈ηn-2〈1,ai(i=1,2,…,n-... This paper deals with the existence of solutions for the problem{(Фp(u′))′=f(t,u,u′),t∈(0,1), u′(0)=0,u(1)=∑i=1^n-2aiu(ηi),where Фp(s)=|s|^p-2s,p〉1.0〈η1〈η2〈…〈ηn-2〈1,ai(i=1,2,…,n-2)are non-negative constants and ∑i=1^n-2ai=1.Some known results are improved under some sign and growth conditions. The proof is based on the Brouwer degree theory. 展开更多
关键词 p-Laplace multi-point boundary value problem RESONANCE degree theory.
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