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Transitivity Analysis of the Energy in China’s New Era
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作者 SHAN Ting WANG Yu 《Journal of Literature and Art Studies》 2024年第2期170-176,共7页
At present,with the steady development of the global economy,more and more countries begin to pay attention to the impact of ecological environment on economic development and human society,so the ecological environme... At present,with the steady development of the global economy,more and more countries begin to pay attention to the impact of ecological environment on economic development and human society,so the ecological environment has become a global issue that cannot be ignored in today’s era.Therefore,from the perspective of the ecological philosophy of Diversity&Harmony as well as Interaction&Co-existence,this paper will conduct ecological discourse analysis on the Energy in China’s New Era based on the transitivity system of systemic-functional grammar,and use the Corpus analysis software UAM Corpus Tool 3.3x to label and make statistics on the transitivity system,aiming to explore the distribution characteristics of the transitivity system in this white paper.Through the transitivity analysis of the white paper,this study helps readers to have a deeper understanding of the positive significance contained in the white paper.To a certain extent,it enables readers at home and abroad to understand China’s stance on energy issues and the positive image of China in energy ecology.It also awaken readers’awareness of environmental protection and acquire good habits of resource conservation to be in harmony between human and nature for sustainable development. 展开更多
关键词 TRANsITIVITY Ecological discourse analysis energy in china’s new era
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Changes of China’s Status in the Global System and Its Influencing Factors:A Multiple Contact Networks Perspective
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作者 LIU Jian LIU Jibin +2 位作者 YANG Qingshan CAI Sikai LIU Jie 《Chinese Geographical Science》 SCIE CSCD 2024年第2期265-279,共15页
Clarifying China’s position in the global system is an important logical basis for developing national diplomacy.Although much research has been done on China’s development status,most studies have been based on cou... Clarifying China’s position in the global system is an important logical basis for developing national diplomacy.Although much research has been done on China’s development status,most studies have been based on country comparisons or institutional en-vironment.In today’s networked era in which the global economy,trade,personnel,and information are closely connected,studies on China’s global position and its status changes and influencing factors in multiple contact networks are still insufficient.In this study,from the perspective of diverse global contact networks,we constructed economic,cultural,and political influence indices to explore the changes and influencing factors on China’s status in the global system from 2005 to 2018.The results show that during the study period,China’s global influence in the fields of economic ties,cultural exchanges,and political contacts increased significantly,but its influ-ence in the fields of cultural exchanges and political contacts lagged far economic ties.The pattern of China’s economic influence on various economies around the world has shown a transformation from an‘upright pyramid’to an‘inverted pyramid’structure.The proportion of these economies in low-influence zones has decreased from more than 60%in 2005 to less than 20%in 2018.China’s cultural and political influence on various economies around the world has increased significantly;however,for the former,the percentage of high-influence areas is still less than 20%,whereas for the latter the percentage of these economies in medium-and high-influence areas is still less than 50%.Analyses such as a scatter plot matrix show that geographical proximity,economic globalization,close cooperation with developing countries,and a proactive and peaceful foreign policy are important factors in improving China’s status in the diverse global network system. 展开更多
关键词 global system economic ties cultural exchanges political contacts multiple contact networks china’s status
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Energy Stable Nodal DG Methods for Maxwell’s Equations of Mixed-Order Form in Nonlinear Optical Media
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作者 Maohui Lyu Vrushali A.Bokil +1 位作者 Yingda Cheng Fengyan Li 《Communications on Applied Mathematics and Computation》 EI 2024年第1期30-63,共34页
In this work,we develop energy stable numerical methods to simulate electromagnetic waves propagating in optical media where the media responses include the linear Lorentz dispersion,the instantaneous nonlinear cubic ... In this work,we develop energy stable numerical methods to simulate electromagnetic waves propagating in optical media where the media responses include the linear Lorentz dispersion,the instantaneous nonlinear cubic Kerr response,and the nonlinear delayed Raman molecular vibrational response.Unlike the first-order PDE-ODE governing equations considered previously in Bokil et al.(J Comput Phys 350:420–452,2017)and Lyu et al.(J Sci Comput 89:1–42,2021),a model of mixed-order form is adopted here that consists of the first-order PDE part for Maxwell’s equations coupled with the second-order ODE part(i.e.,the auxiliary differential equations)modeling the linear and nonlinear dispersion in the material.The main contribution is a new numerical strategy to treat the Kerr and Raman nonlinearities to achieve provable energy stability property within a second-order temporal discretization.A nodal discontinuous Galerkin(DG)method is further applied in space for efficiently handling nonlinear terms at the algebraic level,while preserving the energy stability and achieving high-order accuracy.Indeed with d_(E)as the number of the components of the electric field,only a d_(E)×d_(E)nonlinear algebraic system needs to be solved at each interpolation node,and more importantly,all these small nonlinear systems are completely decoupled over one time step,rendering very high parallel efficiency.We evaluate the proposed schemes by comparing them with the methods in Bokil et al.(2017)and Lyu et al.(2021)(implemented in nodal form)regarding the accuracy,computational efficiency,and energy stability,by a parallel scalability study,and also through the simulations of the soliton-like wave propagation in one dimension,as well as the spatial-soliton propagation and two-beam interactions modeled by the two-dimensional transverse electric(TE)mode of the equations. 展开更多
关键词 Maxwell’s equations Kerr and Raman Discontinuous Galerkin method energy stability
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Understanding the Global Identification with China’s Stories: A Cross-Cultural Perspective
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作者 Fu Chun Deng Da 《Contemporary Social Sciences》 2024年第1期46-57,共12页
Cross-cultural storytelling is a primary way for humankind to seek mutual recognition of value orientations between cultures,which facilitates the ability to jointly address the problems of human existence in the cont... Cross-cultural storytelling is a primary way for humankind to seek mutual recognition of value orientations between cultures,which facilitates the ability to jointly address the problems of human existence in the context of globalization.In this study,we conducted an interview survey of 6,130 respondents who were college students or graduates from 107 countries.The results show that there were a number of cross-cultural values embodied in China’s stories seen by the respondents as part of a common vision for the future of humankind and widely identified guidance on collaborative responses to global challenges.These cross-cultural values are common prosperity,ecological harmony,individual-collective integration,the urgency of global peace,as well as respect for multicultural and indigenous development paths. 展开更多
关键词 china’s stories global identification cross-cultural communication
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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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Geological reservoir and resource potential(10^(13)m^(3))of gas hydrates in the South China Sea
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作者 Pi-bo Su Wei Wei +5 位作者 Yun-bao Sun Yao-yao Lü Huai Cheng Wei-feng Han Wei Zhang Jin-qiang Liang 《China Geology》 CAS CSCD 2024年第3期422-444,共23页
A detailed understanding of the distribution and potential of natural gas hydrate(NGHs)resources is crucial to fostering the industrialization of those resources in the South China Sea,where NGHs are abundant.In this ... A detailed understanding of the distribution and potential of natural gas hydrate(NGHs)resources is crucial to fostering the industrialization of those resources in the South China Sea,where NGHs are abundant.In this study,this study analyzed the applicability of resource evaluation methods,including the volumetric,genesis,and analogy methods,and estimated NGHs resource potential in the South China Sea by using scientific resource evaluation methods based on the factors controlling the geological accumulation and the reservoir characteristics of NGHs.Furthermore,this study compared the evaluation results of NGHs resource evaluations in representative worldwise sea areas via rational analysis.The results of this study are as follows:(1)The gas hydrate accumulation in the South China Sea is characterized by multiple sources of gas supply,multi-channel migration,and extensive accumulation,which are significantly different from those of oil and gas and other unconventional resources.(2)The evaluation of gas hydrate resources in the South China Sea is a highly targeted,stratified,and multidisciplinary evaluation of geological resources under the framework of a multi-type gas hydrate resource evaluation system and focuses on the comprehensive utilization of multi-source heterogeneous data.(3)Global NGHs resources is n×10^(15)m^(3),while the NGHs resources in the South China Sea are estimated to be 10^(13)m^(3),which is comparable to the abundance of typical marine NGHs deposits in other parts of the world.In the South China Sea,the NGHs resources have a broad prospect and provide a substantial resource base for production tests and industrialization of NGHs. 展开更多
关键词 Reservoir characteristics Natural gas hydrates Gas migration Resource potential Resource evaluation methods Hierarchical evaluation system Volumetric method south china sea Clean energy exploration engineering
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Evolution and Governance of the Structure of Marine Economic Networks in China’s Coastal Areas: Based on Sea-related A-share Listed Companies
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作者 LI Bo CAO Gai 《Chinese Geographical Science》 SCIE CSCD 2024年第5期899-916,共18页
Data on discrete,isolated attributes of the marine economy are often used in traditional marine economic research.However,as the focus of urban research shifts from internal static attributes to external dynamic linka... Data on discrete,isolated attributes of the marine economy are often used in traditional marine economic research.However,as the focus of urban research shifts from internal static attributes to external dynamic linkages,the importance of marine economic net-work research is beginning to emerge.The construction of the marine economic network in China’s coastal areas is necessary to change the flow of land and sea resources and optimize regional marine economic development.Employing data from headquarters and branches of sea-related A-share listed enterprises to construct the marine economic network in China,we use social network analysis(SNA)to discuss the characteristics of its evolution as of 2010,2015,and 2020 and its governance.The following results were obtained.1)In terms of topological characteristics,the scale of the marine economic network in China’s coastal areas has accelerated and expan-ded,and the connections have become increasingly close;thus,this development has complex network characteristics.2)In terms of spatial structure,the intensity of the connection fluctuates and does not form stable development support;the group structure gradually becomes clear,but the overall pattern is fragmented;there are spatial differences in marine economic agglomeration radiation;the radi-ation effect of the eastern marine economic circle is obvious;and the polarization effect of northern and southern marine economic circles is significant.On this basis,we construct a framework for the governance of a marine economic network with the market,the government,and industry as the three governing bodies.By clarifying the driving factors and building objectives of marine economic network construction,this study aims to foster the high-quality development of China’s marine economy. 展开更多
关键词 marine economic network sea-related A-share listed companies social network analysis(sNA) network governance china’s coastal areas
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Heuristic Estimation of the Vacuum Energy Density of the Universe: Part II-Analysis Based on Frequency Domain Electromagnetic Radiation
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作者 Vernon Cooray Gerald Cooray +1 位作者 Marcos Rubinstein Farhad Rachidi 《Journal of Electromagnetic Analysis and Applications》 2024年第1期1-9,共9页
In Part I of this paper, an inequality satisfied by the vacuum energy density of the universe was derived using an indirect and heuristic procedure. The derivation is based on a proposed thought experiment, according ... In Part I of this paper, an inequality satisfied by the vacuum energy density of the universe was derived using an indirect and heuristic procedure. The derivation is based on a proposed thought experiment, according to which an electron is accelerated to a constant and relativistic speed at a distance L from a perfectly conducting plane. The charge of the electron was represented by a spherical charge distribution located within the Compton wavelength of the electron. Subsequently, the electron is incident on the perfect conductor giving rise to transition radiation. The energy associated with the transition radiation depends on the parameter L. It was shown that an inequality satisfied by the vacuum energy density will emerge when the length L is pushed to cosmological dimensions and the product of the radiated energy, and the time duration of emission is constrained by Heisenberg’s uncertainty principle. In this paper, a similar analysis is conducted with a chain of electrons oscillating sinusoidally and located above a conducting plane. In the thought experiment presented in this paper, the behavior of the energy radiated by the chain of oscillating electrons is studied in the frequency domain as a function of the length L of the chain. It is shown that when the length L is pushed to cosmological dimensions and the energy radiated within a single burst of duration of half a period of oscillation is constrained by the fact that electromagnetic energy consists of photons, an inequality satisfied by the vacuum energy density emerges as a result. The derived inequality is given by where is the vacuum energy density. This result is consistent with the measured value of the vacuum energy density, which is 5.38 × 10<sup>-10</sup> J/m. The result obtained here is in better agreement with experimental data than the one obtained in Part I of this paper with time domain radiation. 展开更多
关键词 Classical Electrodynamics Electromagnetic Radiation Action Radiated energy PHOTON Heisenberg’s Uncertainty Principle Dark energy Vacuum energy Cosmological Constant Hubble Radius
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Historical review and reflections on the participation of acupuncture and moxibustion in the treatment of epidemics in the People’s Republic of China (from 1950 until now)
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作者 Xiong Xiao 《History & Philosophy of Medicine》 2024年第3期1-5,共5页
Since the establishment of the People’s Republic of China, both the Communist Party and the government have placed great emphasis on the advancement of traditional Chinese medicine. Acupuncture and moxibustion have b... Since the establishment of the People’s Republic of China, both the Communist Party and the government have placed great emphasis on the advancement of traditional Chinese medicine. Acupuncture and moxibustion have been actively involved in combating major epidemics such as malaria, schistosomiasis, and COVID-19. This article conducts a historical review of these three significant cases to elucidate how the acupuncture community has effectively utilized its unique advantages and characteristics through theoretical discussions, clinical practices, experimental research, as well as receiving administrative leadership and political support from the Communist Party of China and government. We provide an objective evaluation of their effectiveness while summarizing historical experiences to serve as a reference for future utilization of acupuncture and moxibustion therapy in epidemic relief efforts. Additionally, propose four suggestions: strengthening Party leadership and enhancing political support;timely summarization of experiences to establish programs and systems;deepening scientific research by integrating experimental findings with clinical practice;focusing on public awareness campaigns and education to solidify grassroots foundations. 展开更多
关键词 acupuncture and moxibustion the People’s Republic of china EPIDEMICs MALARIA sCHIsTOsOMIAsIs COVID-19
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Analysis of New Senior English for China Student’s Book 1
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作者 Xia Qian 《语言与文化研究》 2024年第4期128-132,共5页
This article will firstly discuss the context overview of English teaching and learning in China. Under thiscircumstance, a problematic element will be examined of the New Senior English for China Student’s Book 1 an... This article will firstly discuss the context overview of English teaching and learning in China. Under thiscircumstance, a problematic element will be examined of the New Senior English for China Student’s Book 1 and critical appraisal ofhow this element relates to other elements of curriculum development will be analyzed. The recommended changes and demonstrationmechanisms for evaluating the changes are put forward in the last two parts. 展开更多
关键词 New senior English for china student’s Book 1 Assessment Critical appraisal Curriculum development CHANGEs
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The Magnetic Longitudinal (P-) Wave’s Propagation and Energy Models Underlying the Mechanisms of Its Capacity to Absorb Free Energy
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作者 Jianzhong Jiang Yufeng Wang 《Journal of Power and Energy Engineering》 2024年第7期39-62,共24页
The longitudinal wave term within Faraday’s law of electromagnetic induction (Faraday’s law) underwent recovery to ensure its suitability for theoretical derivation of the equation governing longitudinal electromagn... The longitudinal wave term within Faraday’s law of electromagnetic induction (Faraday’s law) underwent recovery to ensure its suitability for theoretical derivation of the equation governing longitudinal electromagnetic (LEM) waves. The revised Maxwell’s equations include the crucial parameters being the attenuation time constants of magnetic vortex potential and electric vortex potential generated by external electromagnetic field within the propagation medium. Specific expressions for them are obtained through theoretical analysis. Subsequently, a model for propagating magnetic P-wave generated by the superposition of a left-handed photo and a right-handed photon in a vacuum is formulated based on reevaluated total current law and revised Faraday’s law, covering wave equations, energy equation, as well as propagation mode involving mutual induction and conversion between scalar magnetic field and vortex electric field. Furthermore, through theoretical derivations centered around magnetic P-wave, evidence was presented regarding its ability to absorb huge free energy through the entangled interaction between zero-point vacuum energy field and the torsion field produced by the vortex electric field. 展开更多
关键词 QED (Quantum Electrodynamics) energy Wave and TEM (Transverse Electromagnetic) Wave Magnetic P-Wave Modified Faraday’s Law of Electromagnetic Induction Electric/Magnetic Vortex Potential Zero-Point Vacuum energy
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The effect of Typhoon Kalmaegi on the modal energy and period of internal waves near the Dongsha Islands(South China Sea)
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作者 Rongwei Zhai Guiying Chen +2 位作者 Chenjing Shang Xiaodong Shang Youren Zheng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第12期22-31,共10页
The influence of Typhoon Kalmaegi on internal waves near the Dongsha Islands in the northeastern South China Sea was investigated using mooring observation data.We observed,for the first time,that the phenomenon of re... The influence of Typhoon Kalmaegi on internal waves near the Dongsha Islands in the northeastern South China Sea was investigated using mooring observation data.We observed,for the first time,that the phenomenon of regular variation characteristics of the 14-d spring-neap cycle of diurnal internal tides(ITs)can be regulated by typhoons.The diurnal ITs lost the regular variation characteristics of the 14-d spring-neap cycle during the typhoon period owing to the weakening of diurnal coherent ITs,represented by O_(1)and K_(1),and the strengthening of diurnal incoherent ITs.Results of quantitative analysis showed that during the pre-typhoon period,timeaveraged modal kinetic energy(sum of Modes 1–5)of near-inertial internal waves(NIWs)and diurnal and semidiurnal ITs were 0.62 kJ/m^(2),5.66 kJ/m^(2),and 1.48 kJ/m^(2),respectively.However,during the typhoon period,the modal kinetic energy of NIWs increased 5.11 times,mainly due to the increase in high-mode kinetic energy.At the same time,the modal kinetic energy of diurnal and semidiurnal ITs was reduced by 68.9%and 20%,respectively,mainly due to the decrease in low-mode kinetic energy.The significantly reduced diurnal ITs during the typhoon period could be due to:(1)strong nonlinear interaction between diurnal ITs and NIWs,and(2)a higher proportion of high-mode diurnal ITs during the typhoon period,leading to more energy dissipation. 展开更多
关键词 internal waves spring-neap cycle modal kinetic energy south china sea
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Does economic growth stimulate energy consumption?New evidence from national and regional levels in China
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作者 Defu Zhao Jiahai Yuan +4 位作者 Shan Fu Yan Song Yuan Wang Yanyan Liu Jian Zhang 《Chinese Journal of Population,Resources and Environment》 2023年第2期60-70,共11页
A detailed investigation of the nexus between economic growth and energy use is imperative for formulating sustainable development policies.In this study,we examine panel cointegration and causality relations among ec... A detailed investigation of the nexus between economic growth and energy use is imperative for formulating sustainable development policies.In this study,we examine panel cointegration and causality relations among economic growth,energy use,capital stock,and labor in 30 Chinese provinces between 2000-2019.We conduct a comprehensive empirical analysis based on panel modeling and a neoclassical production function.The findings of the second-generation panel unit root and co-integration tests reveal that these variables have long term co-integration linkages.We then perform a panel cointegration estimation using the fully modified ordinary least squares technique and find that total energy consumption,electricity consumption,capital stock,and labor significantly influence economic growth at the national and regional levels in China.Moreover,the outcomes of the Dumitrescu-Hurlin causality test indicate the existence of a two-way causal nexus between economic output and total energy consumption at the national level,but only a causal link from GDP to total energy use in the eastern and central regions.Conversely,a causality from total energy use to economic output is identified in the western region.Finally,we provide policy implications for the sustainable development of both energy and the economy at the national and regional levels. 展开更多
关键词 Economic growth energy consumption Electricity consumption Panel causality china
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Interannual variability of eddy kinetic energy in the South China Sea related to two types of winter circulation events
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作者 Wenlian LI Qinyan LIU +2 位作者 Wendong FANG Tingting ZU Haiying CHEN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第3期831-851,共21页
Interannual variations of the eddy kinetic energy(EKE)related to two types of winter circulation events(“O”and“U”)were investigated based on the outputs of the Ocean General Circulation Model(OGCM)for the Earth Si... Interannual variations of the eddy kinetic energy(EKE)related to two types of winter circulation events(“O”and“U”)were investigated based on the outputs of the Ocean General Circulation Model(OGCM)for the Earth Simulator(OFES)and the corresponding energetic analyses.Results show that the EKE is strong and extends eastward to offshore the Vietnam coast about 2°,associated with the weaker South China Sea western boundary current(SCSwbc)in“O”type years,while the EKE is weak and high value that can be attained is narrowed along the coast,associated with the stronger SCSwbc in“U”type years.The energy budget shows that the wind stress and barotropic/baroclinic instability are important factors to regulate the EKE in“U”and“O”years.For“U”years,under a strong winter monsoon forcing,the SCSwbc strengthen,the directly wind work and barotropic conversion from the mean kinetic energy(MKE)to EKE are weak,thus the EKE decrease corresponding to the baroclinic conversion from the kinetic energy to potential energy.However,the situation is reversed in“O”years.Under the influence of El Niño events,wind stress forces can weaken SCSwbc and enhance EKE in pattern“O”,whereas La Niña events have relatively weaker influences.The barotropic conversion rate in“O”type is nearly eight times of the“U”type.The pressure work and advection term are the main sources to greatly suppress EKE in the SCSwbc region. 展开更多
关键词 two-type winter circulation south china sea western boundary current energy budget
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Analysis of offshore wind energy resources of China 被引量:1
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作者 李希彬 孙晓燕 +1 位作者 李慧颖 张秋丰 《Marine Science Bulletin》 CAS 2015年第2期1-8,共8页
With the economic development, the problems of energy shortage become increasingly severe. As offshore wind energy has advantages, namely it is clean, renewable, not accounting for land area, without noise pollution, ... With the economic development, the problems of energy shortage become increasingly severe. As offshore wind energy has advantages, namely it is clean, renewable, not accounting for land area, without noise pollution, with large reserves, etc., which gradually attracts people's attention. In this paper, China's offshore annual average wind field and monthly average wind field under the mean climate state conditions are obtained, and the corresponding wind density distribution is calculated. China's offshore wind energy reserves and distribution conditions through the analysis of wind energy density distribution are summarized, and finally some suggestions for coastal offshore wind energy development and utilization in China are put forward. 展开更多
关键词 renewable energy offshore wind energy china offshore wind speed wind power density
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基于程函面波成像的华北克拉通岩石圈三维高分辨率S波速度结构研究
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作者 钟世军 吴建平 +2 位作者 司政亚 朱红彬 王薇 《地震学报》 CSCD 北大核心 2024年第4期578-599,共22页
利用“中国地震科学台阵探测”项目Ⅱ期和Ⅲ期的流动地震台站以及中国区域地震台网中的部分固定台站的观测资料,采用程函面波成像方法获得了华北克拉通及周边区域10—120 s周期的瑞雷面波相速度分布和高分辨率的三维S波速度结构,并基于... 利用“中国地震科学台阵探测”项目Ⅱ期和Ⅲ期的流动地震台站以及中国区域地震台网中的部分固定台站的观测资料,采用程函面波成像方法获得了华北克拉通及周边区域10—120 s周期的瑞雷面波相速度分布和高分辨率的三维S波速度结构,并基于该速度模型估算了岩石圈厚度分布。结果显示,华北克拉通内部岩石圈厚度除了存在“西厚东薄”的一级分布特征外,还存在一些更小尺度的差异,包括鄂尔多斯地块内部岩石圈“南厚北薄”、鄂尔多斯地块周缘断陷带岩石圈显著的不均匀减薄以及燕山构造带与其南侧华北平原之间的显著差异等。山西断陷带北部与南部地区上地幔浅部(<100 km)存在不同程度的低速异常,它们被中部的高速异常区所分隔。在150 km以下深度从太行山南缘向北至山西断陷北缘存在一条NNE向展布的显著低速异常带,表明上地幔浅部南北部的低速异常在深部相连。结合已有的其它成像结果,我们推测这些低速异常起源于更深处(>200 km),并与由太平洋俯冲板块的滞留脱水导致的上地幔热物质上涌和小尺度地幔对流等密切相关。燕山构造带与华北平原的岩石圈结构存在明显差异,前者遭受的岩石圈破坏改造程度明显弱于后者,张家口—渤海地震带位于这两种不同壳幔结构的过渡带,地震活动较强,我们认为深部结构和热作用的显著差异,以及青藏高原远场挤压效应的共同作用是导致该区地震活动较强的主要原因。 展开更多
关键词 华北克拉通 程函面波成像 s 波速度 低速异常 岩石圈厚度 显著差异
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基于S变换模能量分析的直流电缆故障测距
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作者 夏向阳 刘奕玹 +3 位作者 刘雄 夏君山 王瑞琪 朱鹏 《高压电器》 CAS CSCD 北大核心 2024年第7期201-209,共9页
针对现有高压直流电缆故障定位方法故障定位精度低、定位模型泛化能力差等问题,文中在考虑电缆故障后故障点产生的暂态信号中含有丰富的故障信息的特征,提出一种时频域能量分析的故障测距方法。该方法利用多分类支持向量机(SVM)的特性... 针对现有高压直流电缆故障定位方法故障定位精度低、定位模型泛化能力差等问题,文中在考虑电缆故障后故障点产生的暂态信号中含有丰富的故障信息的特征,提出一种时频域能量分析的故障测距方法。该方法利用多分类支持向量机(SVM)的特性构建直流电缆故障定位模型,利用直流电缆相模解耦矩阵对电缆电气量解耦,并采用S变换进行时频域变换,将得到的模量构造模能量,将其作为样本对SVM模型训练。实验结果表明,所提方法对于不同故障类型在不同过渡电阻及不同位置故障下均可进行准确测距。 展开更多
关键词 s变换 sVM模型 相模解耦 模能量 故障定位
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A wave energy resource assessment in the China's seas based on multi-satellite merged radar altimeter data 被引量:15
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作者 WAN Yong ZHANG Jie +1 位作者 MENG Junmin WANG Jing 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第3期115-124,共10页
Wave energy resources are abundant in both offshore and nearshore areas of the China's seas. A reliable assessment of the wave energy resources must be performed before they can be exploited. First, for a water depth... Wave energy resources are abundant in both offshore and nearshore areas of the China's seas. A reliable assessment of the wave energy resources must be performed before they can be exploited. First, for a water depth in offshore waters of China, a parameterized wave power density model that considers the effects of the water depth is introduced to improve the calculating accuracy of the wave power density. Second, wave heights and wind speeds on the surface of the China's seas are retrieved from an AVISO multi-satellite altim-eter data set for the period from 2009 to 2013. Three mean wave period inversion models are developed and used to calculate the wave energy period. Third, a practical application value for developing the wave energy is analyzed based on buoy data. Finally, the wave power density is then calculated using the wave field data. Using the distribution of wave power density, the energy level frequency, the time variability indexes, the to-tal wave energy and the distribution of total wave energy density according to a wave state, the offshore wave energy in the China's seas is assessed. The results show that the areas of abundant and stable wave energy are primarily located in the north-central part of the South China Sea, the Luzon Strait, southeast of Taiwan in the China's seas; the wave power density values in these areas are approximately 14.0–18.5 kW/m. The wave energy in the China’s seas presents obvious seasonal variations and optimal seasons for a wave energy utilization are in winter and autumn. Except for very coastal waters, in other sea areas in the China's seas, the energy is primarily from the wave state with 0.5 m≤Hs≤4 m, 4 s≤Te≤10 s whereHs is a significant wave height andTe is an energy period; within this wave state, the wave energy accounts for 80% above of the total wave energy. This characteristic is advantageous to designing wave energy convertors (WECs). The practical application value of the wave energy is higher which can be as an effective supplement for an energy con-sumption in some areas. The above results are consistent with the wave model which indicates fully that this new microwave remote sensing method altimeter is effective and feasible for the wave energy assessment. 展开更多
关键词 chinas seasmulti-satellite merged altimeter data wave energy resources assessment wave power density
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Analysis on energy demand and CO2 emissions in China following the Energy Production and Consumption Revolution Strategy and China Dream target 被引量:20
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作者 LI Ji-Feng MA Zhong-Yu +1 位作者 ZHANG Ya-Xiong WEN Zhi-Chao 《Advances in Climate Change Research》 SCIE CSCD 2018年第1期16-26,共11页
A quantitative model was applied to analyze the energy demand and CO2 emissions in China following the Energy Production and Consumption Revolution Strategy(2016e2030)and long-term economic and social development targ... A quantitative model was applied to analyze the energy demand and CO2 emissions in China following the Energy Production and Consumption Revolution Strategy(2016e2030)and long-term economic and social development target China Dream.Results showed that 1)toward the 2050 China Dream target,total final energy consumption is expected to peak at 3.9 Gtce in 2030 and remain stable until 2050,whereas total primary energy consumption is expected to reach an upper platform by 2040 and around 5.8 Gtce by 2050;2)the proportion of non-fossil fuels is expected to reach approximately 50%and that of natural gas to reach more than 16%by 2050;3)CO2 emissions from energy use are expected to peak at 9.6 Gt by no later than 2030 and then gradually decline to 6.7 Gt by 2050. 展开更多
关键词 china energy sTRATEGY china DREAM sTRATEGY CO2 emission PATHWAY energy DEMAND and supply model
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Features of eddy kinetic energy and variations of upper circulation in the South China Sea 被引量:15
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作者 贺志刚 王东晓 胡建宇 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2002年第2期305-314,共10页
The features of eddy kinetic energy (EKE) and the variations of upper circulation in theSouth China Sea (SCS) are discussed in this paper using geostrophic currents estimated from Maps of Sea Level Anomalies of the TO... The features of eddy kinetic energy (EKE) and the variations of upper circulation in theSouth China Sea (SCS) are discussed in this paper using geostrophic currents estimated from Maps of Sea Level Anomalies of the TOPEX/Poseidon altimetry data. A high EKE center is identified in the southeast of Vietnam coast with the highest energy level 1 400 cm2 ·s^(-2) in both summer and autumn. This high EKE center is caused by the instability of the current axis leaving the coast of Vietnam in summer and the transition of seasonal circulation patterns in autumn. There exists another high EKE region in the northeastern SCS, southwest to Taiwan Island in winter. This high EKE region is generated from the eddy activities caused by the Kuroshio intrusion and accumulates more than one third of the annual EKE, which confirms that the eddies are most active in winter. The transition of upper circulation patterns is also evidenced by the directions of the major axises of velocity variance ellipses between 10?and 14.5°N, which supports the model results reported before. 展开更多
关键词 The south china sea eddy kinetic energy TOPEX/POsEIDON upper circulation altimeter data
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