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正“△”模式与资产重组
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作者 张幸福 《企业管理》 CSSCI 北大核心 2001年第6期79-81,共3页
关键词 企业资产重组 影响因素 正“△”模式 基本结论
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家属协同干预在抗磷脂综合征合并妊娠患者中的应用效果
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作者 李伏一 肖兰凤 《中国医药导报》 CAS 2024年第5期160-164,共5页
目的探讨家属协同干预在抗磷脂综合征(APS)合并妊娠患者中的应用效果。方法选择2020年1月至2022年12月内蒙古医科大学附属医院收治的100例APS合并妊娠患者,根据随机数字表法将其分为甲组和乙组,每组50例。甲组予以常规护理,乙组在甲组... 目的探讨家属协同干预在抗磷脂综合征(APS)合并妊娠患者中的应用效果。方法选择2020年1月至2022年12月内蒙古医科大学附属医院收治的100例APS合并妊娠患者,根据随机数字表法将其分为甲组和乙组,每组50例。甲组予以常规护理,乙组在甲组基础上行家属协同干预。观察两组干预前后情绪状态、自我护理能力、服药依从性及妊娠并发症发生情况。结果干预后,两组正性负性情绪量表中正性情绪评分高于干预前,负性情绪评分低于干预前,且乙组正性情绪评分高于甲组,负性情绪评分低于甲组,差异有统计学意义(P<0.05);干预后,两组自我护理能力测定量表及中文版8条目Morisky服药依从性量表评分均高于干预前,且乙组高于甲组,差异有统计学意义(P<0.05)。结论家属协同干预可改善APS妊娠者情绪状态、自我护理能力及用药依从性,并可减少其他妊娠并发症。 展开更多
关键词 抗磷脂综合征 妊娠 家属协同干预 服药依从性 并发症
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Models for amplitude fluctuation of underwater acoustic narrow band signal based on modified modal scintillation index 被引量:2
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作者 安良 方世良 陈励军 《Journal of Southeast University(English Edition)》 EI CAS 2013年第3期235-241,共7页
A self-normalized statistic the modified modal scintillation index MMSI is proposed and defined as the variance of the modulus of modal excitation normalized by the square of its expected value over some observation i... A self-normalized statistic the modified modal scintillation index MMSI is proposed and defined as the variance of the modulus of modal excitation normalized by the square of its expected value over some observation intervals.It is proved in an analytical form that the MMSI is a depth dependent signature and independent of the source level and the source range under the condition of the ideal waveguide while the classical modal scintillation index MSI depends on both the source level and the source range.The MSI and the MMSI in the Pekeris waveguide at 70 Hz are simulated with different source levels and source ranges by the Kraken normal mode model.The simulation results are consistent with the theoretical deduction.The MMSI probability density functions PDFs of different normal modes for surface and submerged sources are calculated using the mode filtering methods with the same variations of vertical motions.It is indicated that the PDFs can be used to separate the submerged and the surface sources except for the fourth mode. 展开更多
关键词 modified modal scintillation index amplitudefluctuation mode filtering Pekeris waveguide
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NUMERICAL SIMULATION OF SUPERSONIC AXISYMMETRIC FLOW OVER MISSILE AFTERBODY WITH JET EXHAUST USING POSITIVE SCHEMES 被引量:1
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作者 朱孙科 马大为 +1 位作者 陈二云 乐贵高 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第3期255-261,共7页
Supersonic axisymmetric jet flow over a missile afterbody containing exhaust jet is simulated using the second order accurate positive schemes method developed for solving the axisymmetric Euler equations based on the... Supersonic axisymmetric jet flow over a missile afterbody containing exhaust jet is simulated using the second order accurate positive schemes method developed for solving the axisymmetric Euler equations based on the 2-D conservation laws.Comparisons between the numerical results and the experimental measurements show excellent agreements.The computed results are in good agreement with the numerical solutions obtained by using third order accurate RKDG finite element method.The results show larger gradient at discontinuous points compared with those obtained by second order accurate TVD schemes.It indicates that the presented method is efficient and reliable for solving the axisymmetric jet with external freestream flows,and shows that the method captures shocks well without numerical noise. 展开更多
关键词 computational fluid dynamics supersonic flow positive schemes numerical simulation
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Correction of Corporation Value Assessment Model Based on Corporate Social Responsibility
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作者 贠晓兰 《Agricultural Science & Technology》 CAS 2017年第4期736-739,共4页
The performance of corporate social responsibility is conducive to the con- tinuous improvement of their profitability, and promotes the upgrading of corporation value. However, it is difficult to confirm, calculate a... The performance of corporate social responsibility is conducive to the con- tinuous improvement of their profitability, and promotes the upgrading of corporation value. However, it is difficult to confirm, calculate and check the costs and benefits brought by the implementation of corporate social responsibility under the current ac- counting theory system, so it is difficult to estimate whether the fulfillment of corpo- rate social responsibility has any effects on the corporation value assessment. Therefore, based on corporate social responsibility, the correction mode of corpora- tion value assessment is put forward. 展开更多
关键词 Corporation value Social responsibility Assessment model Correction model
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REFINED HYBRID MINDLIN PLATE ELEMENT FOR GEOMETRICALLY NON LINEAR ANALYSIS
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作者 郑世杰 陶宝祺 陈万吉 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2000年第1期90-94,共5页
Based upon a generalized variational principle, which relaxed the inter element continuity requirements, a novel refined hybrid Mindlin plate element is developed, its non linear element stiffness matrices are decom... Based upon a generalized variational principle, which relaxed the inter element continuity requirements, a novel refined hybrid Mindlin plate element is developed, its non linear element stiffness matrices are decomposed into a series of matrices with respect to the assumed strain modes. The formulation presented in this paper is different from any other non linear mixed/hybrid element formulation all successful experience of linear hybrid formulation is absorbed into the formulation(adding non conforming modes and realizing orthogonalization) Numerical results show that the present approach is more effective than any other non linear hybrid element formulation over the accuracy and computational efficiency. In addition, non conforming modes can also overcome the shear locking effect. 展开更多
关键词 non linear mechanics non conforming mode orthogonal approach geometrically non linear refined element
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Approximation to NLAR(p) with Wavelet Neural Networks
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作者 朱石焕 吴曦 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第4期94-98,共5页
Recently, wavelet neural networks have become a popular tool for non-linear functional approximation. Wavelet neural networks, which basis functions are orthonormal scalling functions, are more suitable in approximati... Recently, wavelet neural networks have become a popular tool for non-linear functional approximation. Wavelet neural networks, which basis functions are orthonormal scalling functions, are more suitable in approximating to function. Based on it, approximating to NLAR(p) with wavelet neural networks is studied. 展开更多
关键词 wavelet neural networks orthonormal scaling functions NLAR(p)
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The Classification of Positive Definite Unimodular Lattices Over Z[(1+211/2)/2] 被引量:4
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作者 王瑞卿 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第2期87-93,共页
In this paper, the author applies adjacent lattice method and Siegel mass formula to determine the classes of positive definite unimodular lattices of rank 4 over Z , and obtains that the class number of unit genus ... In this paper, the author applies adjacent lattice method and Siegel mass formula to determine the classes of positive definite unimodular lattices of rank 4 over Z , and obtains that the class number of unit genus gen( I 4 ) is nine and the class number of even unimodular lattices is three, and also gives the representative lattices of each class. 展开更多
关键词 positive definite unimodular adjacent lattice class number Siegel mass formula orthogonal group
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IMC based robust PID controller tuning for disturbance rejection 被引量:5
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作者 Mohammad Shamsuzzoha 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第3期581-597,共17页
It is well-known that the IMC-PID controller tuning gives fast and improved set point response but slow disturbance rejection. A modification has been proposed in IMC-PID tuning rule for the improved disturbance rejec... It is well-known that the IMC-PID controller tuning gives fast and improved set point response but slow disturbance rejection. A modification has been proposed in IMC-PID tuning rule for the improved disturbance rejection. For the modified IMC-PID tuning rule, a method has been developed to obtain the IMC-PID setting in closed-loop mode without acquiring detailed information of the process. The proposed method is based on the closed-loop step set point experiment using a proportional only controller with gain K_(c0). It is the direct approach to find the PID controller setting similar to classical Ziegler-Nichols closed-loop method. Based on simulations of a wide range of first-order with delay processes, a simple correlation has been derived to obtain the modified IMC-PID controller settings from closed-loop experiment. In this method, controller gain is a function of the overshoot obtained in the closed loop set point experiment. The integral and derivative time is mainly a function of the time to reach the first peak(overshoot). Simulation has been conducted for the broad class of processes and the controllers were tuned to have the same degree of robustness by measuring the maximum sensitivity, Ms, in order to obtain a reasonable comparison. The PID controller settings obtained in the proposed tuning method show better performance and robustness with other two-step tuning methods for the broad class of processes. It has also been applied to temperature control loop in distillation column model. The result has been compared to the open loop tuning method where it gives robust and fast response. 展开更多
关键词 PI/PID controller step test closed-loop response IMC-PID OVERSHOOT
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Model of wind-generated ambient noise in stratified shallow water 被引量:3
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作者 林建恒 高天赋 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2005年第2期144-151,共8页
In order to build a rapid ocean ambient noise model adapted for a stratified shallow water, a hybrid model of normal mode method (for far field) and ray method (for near field) is suggested which combines the advantag... In order to build a rapid ocean ambient noise model adapted for a stratified shallow water, a hybrid model of normal mode method (for far field) and ray method (for near field) is suggested which combines the advantages of both methods. Since the near field of wind-generated noise is not sensitive to the sound speed pro- file, the sound speed profile is regarded as a constant; which makes the model rapid and accurate. The simulation results are in agreement with those of the wave model. 展开更多
关键词 wind-generated ambient noise RAY normal mode hybrid model
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Single-trial EEG-based emotion recognition using temporally regularized common spatial pattern
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作者 成敏敏 陆祖宏 王海贤 《Journal of Southeast University(English Edition)》 EI CAS 2015年第1期55-60,共6页
This study addresses the problem of classifying emotional words based on recorded electroencephalogram (EEG) signals by the single-trial EEG classification technique. Emotional two-character Chinese words are used a... This study addresses the problem of classifying emotional words based on recorded electroencephalogram (EEG) signals by the single-trial EEG classification technique. Emotional two-character Chinese words are used as experimental materials. Positive words versus neutral words and negative words versus neutral words are classified, respectively, using the induced EEG signals. The method of temporally regularized common spatial patterns (TRCSP) is chosen to extract features from the EEG trials, and then single-trial EEG classification is achieved by linear discriminant analysis. Classification accuracies are between 55% and 65%. The statistical significance of the classification accuracies is confirmed by permutation tests, which shows the successful identification of emotional words and neutral ones, and also the ability to identify emotional words. In addition, 10 out of 15 subjects obtain significant classification accuracy for negative words versus neutral words while only 4 are significant for positive words versus neutral words, which demonstrate that negative emotions are more easily identified. 展开更多
关键词 emotion recognition temporal regularization common spatial patterns(CSP) two-character Chinese words permutation test
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Study on Health Monitoring Systems Based on Correction Mode
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作者 ZHU Tianyang ZHANG Yajun +1 位作者 ZHOU Junliang ZHOU Aotu 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2021年第2期325-332,共8页
Current health monitoring systems often do not concern about the needs of the elderly,leading to inaccurate health status monitoring and delayed treatment for emergency health conditions.Similarly,they do not consider... Current health monitoring systems often do not concern about the needs of the elderly,leading to inaccurate health status monitoring and delayed treatment for emergency health conditions.Similarly,they do not consider the variable factors affecting each patient,resulting in discrepancies between the measured values and real health status.To solve the problems,we propose a new health monitoring system with physiological parameter measurement,correction,and feedback.The study collects clinical samples of the elderly to formulate regression equations and statistical models for analyzing the relationship between gender,age,measurement time,and physical signs.After multiple adjustments to measurements of physical signs,the correction algorithm compares the data with a standard value.The process significantly reduces the risk of misjudgment while matching users’health status more accurately.The application case of this paper proves the validity of the method for measuring and correcting heart rate results in the elderly and presents a specific correction procedure.Additionally,the correction algorithm provides a scientific basis for eliminating or modifying other influencing factors in future health monitoring studies. 展开更多
关键词 health monitoring correction mode algorithm design heart rate
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Product Vibrational State Distributions of F+CH_(3)OH Reaction on Full-Dimensional Accurate Potential Energy Surface
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作者 Meng Zhang Yongfa Zhu Jun Li 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第1期153-166,I0064,共15页
The hydrogen abstraction reaction of methanol with fluorine atoms can produce HF and CH_(3)O or CH_(2)OH radicals,which are important in the environment,combustion,radiation,and interstellar chemistry.In this work,the... The hydrogen abstraction reaction of methanol with fluorine atoms can produce HF and CH_(3)O or CH_(2)OH radicals,which are important in the environment,combustion,radiation,and interstellar chemistry.In this work,the dynamics of this typical reaction is investigated by the quasi-classical trajectory method based on a recently developed globally accurate full-dimensional potential energy surface.Particularly,the vibrational state distributions of the polyatomic products CH_(3)O and CH_(2)OH are determined by using the normal mode analysis method.It is found that CH_(3)O and CH_(2)OH are dominantly populated in the ground state when the reactants are at the ground ro-vibrational state.The OH stretching mode,torsional mode,H_(2)CO out-of-plane bending mode and their combination bands in the CH_(2)OH product can be effectively excited once the OH stretching mode of the reactant CH_(3)OH is excited to the first vibrationally excited state.Most of the available energy flows into the HF vibrational energy and the translational energy in both channels,while the radical products,CH_(3)O or CH_(2)OH,receive a small amount of energy,consistent with experiment,which is an indication of its spectator nature. 展开更多
关键词 Normal mode analysis Potential energy surface CH_(3)OH Product energy partitioning Hydrogen abstraction reaction
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MODELING FUZZY GEOGRAPHIC OBJECTS WITHIN FUZZY FIELDS 被引量:1
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作者 LIU WenbaoXIA Zongguo DENG Min 《Geo-Spatial Information Science》 2001年第4期37-42,共6页
To improve the current GIS functions in describing geographic objects with fuzziness,this paper begins with a discussion on the distance measure of spatial objects based on the theory of sets and an introduction of di... To improve the current GIS functions in describing geographic objects with fuzziness,this paper begins with a discussion on the distance measure of spatial objects based on the theory of sets and an introduction of dilation and erosion operators.Under the assumption that changes of attributes in a geographic region are gradual,the analytic expressions for the fuzzy objects of points,lines and areas,and the description of their formal structures are presented.The analytic model of geographic objects by means of fuzzy fields is developed.We have shown that the 9-intersection model proposed by Egenhofer and Franzosa (1991) is a special case of the model presented in the paper. 展开更多
关键词 fuzzy fields geographic objects formal description
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Channel Capacity of DWDM Networks with Cross-phase Modulation Effect
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作者 QI Jun-xuan WEN Shuang-cun 《Semiconductor Photonics and Technology》 CAS 2006年第1期51-53,共3页
In dense wavelength division multiplexing(DWDM) optical transmission systems, cross phase modulation(XPM) due to Kerr effect causes phase shift and intensity modulation in each channel, which will lead the channel cap... In dense wavelength division multiplexing(DWDM) optical transmission systems, cross phase modulation(XPM) due to Kerr effect causes phase shift and intensity modulation in each channel, which will lead the channel capacity to be a random variable. An expression of the channel capacity dealing with XPM effect is presented, and the correctness and accuracy of this method are demonstrated by numerical simulation. 展开更多
关键词 Fiber nonlinearity Information theory Optical fiber communication systems Cross-phase modulation
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China's Round-Tripped FDI: Trends,Determinants, and Policy Implications
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作者 姜子叶 范从来 《China Economist》 2011年第2期76-85,共10页
With observations and reflections on a series of phenomena,such as the "independent situation"of China's FDI during the recent global financial risis and the increase of round tripped investment after the "tax rat... With observations and reflections on a series of phenomena,such as the "independent situation"of China's FDI during the recent global financial risis and the increase of round tripped investment after the "tax rate unification,"this paper examines a unique phenomenon in China's FDI-round tripped investment.It reveals its determinants from a micro-perspectiv ,and establishes a vector error correction mode(VECM)for emprirical testing.The results is that the determinants of China's round tripped investment are institutional factors such as "achievable differential treatment" and cpaital control.Tax ,exchange rate,housing price and capital control intensity all have an impact on the scale of round tripped FDI.However,judging from the extent of influence,the most important factor should be exchange rate ,followed by capital control intensity and housing price,and tax has a limited impact. 展开更多
关键词 round-tripped FDI achievable differential treatment capital regulation DETERMINANT
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Environmental regulation and trade pattern:a case of China
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作者 Qi Jianhong Zheng Yingmei Zhao Yong 《Ecological Economy》 2007年第3期234-242,共9页
As a growing number of countries, including both developed and developing countries, have in recent yearstaken environmental regulation at different levels, a question of great concern has been raised: can the regulat... As a growing number of countries, including both developed and developing countries, have in recent yearstaken environmental regulation at different levels, a question of great concern has been raised: can the regulation alterthe existing trade volume and trade pattern, and ultimately drive pollution-intensive industries to countries with low-levelregulations or even those without regulations at all? Starting from the three different propositions concerning therelationship between environmental regulation and trade pattern, this paper applies cointegration analysis and errorcorrection model to empirically testing the relationship between environmental regulation and trade in China during theperiod of 1985-2005. Our empirical results indicate that in the short run the collection of pollution discharge fees bearsa positive impact on the export share of clean products of total exports. Thus, higher pollution discharge fees raise theratio of clean products exports to total exports. This further indicates that more stringent environmental regulationpromotes the exports of clean products. In the long run pollution discharge fees are positively correlated with the exportshare of clean products but negatively associated with their import share. Such correlations imply that environmentalregulation tends to facilitate the international specialization in line with comparative advantages. 展开更多
关键词 Environmental regulation Trade pattern Cointegration analysis Error correction model
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Correlation Between Energy Transfer Rate and Atomization Energy of Some Trinitro Aromatic Explosive Molecules
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作者 Su-hong Ge Xin-lu Cheng +2 位作者 Zheng-lai Liu Xiang-dong Yang Fang-fang Dong 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第3期250-254,共5页
An assumptive theoretical relationship is suggested to describe the property of molecular atomization energy and energy transfer rate in the initiation of explosions. To investigate the relationship between atomizatio... An assumptive theoretical relationship is suggested to describe the property of molecular atomization energy and energy transfer rate in the initiation of explosions. To investigate the relationship between atomization energy and energy transfer rate, the number of doorway modes of explosives is estimated by the theory of Dlott and Fayer in which the rate is proportional to the number of normal mode vibrations. It was evaluated frequencies of normal mode vibrations of eight molecules by means of density functional theory (DFT) at the b3p86/6-31G(d,p) level. It is found that the number of doorway modes shows a linear correlation to the atomization energies of the molecules, which were also calculated by means of the same method. A mechanism of this correlation is discussed. It is also noted that in those explosives with similar molecular structure and molecular weight, the correlation between the atomization energy and the number of doorway modes is higher. 展开更多
关键词 Secondary explosive Atomization energy Normal mode vibration Doorway region
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Ensemble Simulations of a Nonlinear Barotropic Model for the North Atlantic Oscillation
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作者 ZHANG Dong-Bin JIN Fei-Fei +1 位作者 LI Jian-Ping DING Rui-Qiang 《Atmospheric and Oceanic Science Letters》 2010年第5期277-282,共6页
A numerical ensemble-mean approach was employed to solve a nonlinear barotropic model with chastic basic flows to analyze the nonlinear effects in the formation of the North Atlantic Oscillation (NAO). The nonlinear... A numerical ensemble-mean approach was employed to solve a nonlinear barotropic model with chastic basic flows to analyze the nonlinear effects in the formation of the North Atlantic Oscillation (NAO). The nonlinear response to external forcing was more similar to the NAO mode than the linear response was, indicating the importance of nonlinearity. With increasing external forcing and enhanced low-frequency anomalies, the effect of nonlinearity increased. Therefore, for strong NAO events, nonlinearity should be considered. 展开更多
关键词 ensemble-mean NAO NONLINEARITY
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Projection of temperature change and extreme temperature events in the Lancang–Mekong River basin 被引量:4
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作者 SUN Chang XIAO Ziniu +1 位作者 SUN Jianqi YU Entao 《Atmospheric and Oceanic Science Letters》 CSCD 2020年第1期16-25,共10页
The Lancang–Mekong River basin(LMRB) is under increasing threat from global warming. In this paper, the projection of future climate in the LMRB is explored by focusing on the temperature change and extreme temperatu... The Lancang–Mekong River basin(LMRB) is under increasing threat from global warming. In this paper, the projection of future climate in the LMRB is explored by focusing on the temperature change and extreme temperature events. First, the authors evaluate the bias of temperature simulated by the Weather Research and Forecasting model. Then, correction is made for the simulation by comparing with observation based on the non-parametric quantile mapping using robust empirical quantiles(RQUANT) method. Furthermore, using the corrected model results, the future climate projections of temperature and extreme temperature events in this basin during 2016–35, 2046–65, and 2080–99 are analyzed. The study shows that RQUANT can effectively reduce the bias of simulation results. After correction, the simulation can capture the spatial features and trends of mean temperature over the LMRB, as well as the extreme temperature events. Besides, it can reproduce the spatial and temporal distributions of the major modes. In the future, the temperature will keep increasing, and the warming in the southern basin will be more intense in the wet season than the dry season. The number of extreme high-temperature days exhibits an increasing trend, while the number of extreme low-temperature days shows a decreasing trend. Based on empirical orthogonal function analysis, the dominant feature of temperature over this basin shows a consistent change. The second mode shows a seesaw pattern. 展开更多
关键词 Climate projection Lancang–Mekong River basin model evaluation bias correction extreme temperature events
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