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The Ecological Crisis and the Principle of Relationality in African Philosophy
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作者 Mark Omorovie Ikeke 《Journal of Philosophy Study》 2015年第4期179-186,共8页
The way that humans think about the earth certainly affects the way that they relate and behave towards the earth and all its life forms. The various ideologies or worldviews that humanity has experienced such as dual... The way that humans think about the earth certainly affects the way that they relate and behave towards the earth and all its life forms. The various ideologies or worldviews that humanity has experienced such as dualism, capitalism, holism, animism, ubuntu, ukama, vital force, colonialism, and so forth are all different ways of thinking and relating to the earth. The paper argues that dualistic ways of thinking or viewpoints that radically separate the human as distinct from the earth are hostile to both human and earth flourishing. It further argues that the ecological crisis which has witnessed the destruction and pollution of the ecosystems and other devastations cannot be solved when humans continue to see the earth as an object for conquest and exploitation. Using a critical hermeneutics method, the paper affirms that the African principle of relationality can help in mitigating the environmental crisis. It finds and concludes that if this principle is radically practiced, a better environment will be created. 展开更多
关键词 ecology relationality Afi'ican PHILOSOPHY UBUNTU vital force
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Relationality and processual construction: bringing Chinese ideas into international relations theory 被引量:7
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作者 Qin Yaqing 《Social Sciences in China》 2009年第4期5-20,共16页
The three mainstream International Relations theories that have arisen in the past thirty years, structural realism, neo-liberal institutionalism and structural constructivism, have all missed an important dimension, ... The three mainstream International Relations theories that have arisen in the past thirty years, structural realism, neo-liberal institutionalism and structural constructivism, have all missed an important dimension, i.e., the study relational complexity in international society. of processes in the international system and of This paper, informed by social constructivism and Chinese philosophical traditions, aims to make up for this missing link and develop a theoretical model of processual constructivism by incorporating and conceptualizing two key Chinese ideas - processes and relations. "Process," defined as relations in motion, can stand on its own, has its own dynamics, and plays a crucial role in international relations. The core of process, by definition, consists in relations. If "rationality," rooted in individuality, has been a key concept for Western society, then its counterpart in Chinese society can be "relationality." Conceptualizing relationality and treating it as the theoretical hard core, processual constructivism holds that relational networking in international society helps nation-states form their identities and produces international power. Processual constructivism is an evolution theory at systemic level, focusing on interactive practices among states and emphasizing the independent ontology of social processes which play a meaningful role in constructing international norms and state identities. 展开更多
关键词 international relations theory processual constructivism relationality international norms state identities
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Effective implementation of controlled blasting methodology during excavation of hard rock in the close proximity of earthen dam and tunnel 被引量:1
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作者 Prakash K.Palei Vijay K.Ghodake +5 位作者 S.Santhosh Kumar R.S.Gurjar Chaman Singh M.Meena Rizwan Ali R.S.Kankara 《Defence Technology(防务技术)》 2025年第6期306-316,共11页
The present technical paper outlines the details of the controlled blasting techniques used to optimize blasting pattern for excavation of hard rock near the Bhira Earthen Dam in Maharashtra,India.In this connection,a... The present technical paper outlines the details of the controlled blasting techniques used to optimize blasting pattern for excavation of hard rock near the Bhira Earthen Dam in Maharashtra,India.In this connection,a series of experimental blasts were conducted by adjusting various blast design parameters at project site.The safe charge weight per delay was kept between 0.125 and 0.375 kg.The outcomes of these experimental blasts were analyzed to recommend optimized blasting patterns and methods for the overall excavation process during actual blasting operations.Blast design parameters,including the maximum quantity of explosive per delay,hole depth,burden and spacing between holes were optimized by using a site-specific attenuation equation,taking into account the proximity of the dam and tunnel from the blasting area.Peak particle velocity(PPV)level of 10 mm/s and 50 mm/s respectively were adopted as the safe vibration level for ensuring safety of the Bhira Earthen Dam and the nearby tunnel from the adverse effects of blast vibrations by analyzing the dominant frequency of ground vibrations observed and also by reviewing various international standards.Frequency of the ground vibrations observed on the dam and tunnel from majority of the blasts was found to be more than 10 Hz and 50 Hz respectively.During the entire period of blasting,the blast vibrations were recorded to be far lower than the safe vibration level set for these structures.Maximum Vibration level of about 0.8 mm/s and 35 mm/s were observed on dam and tunnel respectively which are far lower than the safe vibration level adopted for these structures.Hence,the entire excavation work was completed successfully and safely,without endangering the safety of dam or tunnel. 展开更多
关键词 Controlled blasting Civil structure Ground vibration Attenuation relation
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Chinese satellite frequency and orbit entity relation extraction method based on dynamic integrated learning 被引量:1
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作者 Yuanzhi He Zhiqiang Li Zheng Dou 《Digital Communications and Networks》 2025年第3期787-794,共8页
Given the scarcity of Satellite Frequency and Orbit(SFO)resources,it holds paramount importance to establish a comprehensive knowledge graph of SFO field(SFO-KG)and employ knowledge reasoning technology to automatical... Given the scarcity of Satellite Frequency and Orbit(SFO)resources,it holds paramount importance to establish a comprehensive knowledge graph of SFO field(SFO-KG)and employ knowledge reasoning technology to automatically mine available SFO resources.An essential aspect of constructing SFO-KG is the extraction of Chinese entity relations.Unfortunately,there is currently no publicly available Chinese SFO entity Relation Extraction(RE)dataset.Moreover,publicly available SFO text data contain numerous NA(representing for“No Answer”)relation category sentences that resemble other relation sentences and pose challenges in accurate classification,resulting in low recall and precision for the NA relation category in entity RE.Consequently,this issue adversely affects both the accuracy of constructing the knowledge graph and the efficiency of RE processes.To address these challenges,this paper proposes a method for extracting Chinese SFO text entity relations based on dynamic integrated learning.This method includes the construction of a manually annotated Chinese SFO entity RE dataset and a classifier combining features of SFO resource data.The proposed approach combines integrated learning and pre-training models,specifically utilizing Bidirectional Encoder Representation from Transformers(BERT).In addition,it incorporates one-class classification,attention mechanisms,and dynamic feedback mechanisms to improve the performance of the RE model.Experimental results show that the proposed method outperforms the traditional methods in terms of F1 value when extracting entity relations from both balanced and long-tailed datasets. 展开更多
关键词 Knowledge graph Relation extraction One-class classification Satellite frequency and orbit resources BERT
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PROOFS OF CONJECTURES ON RAMANUJAN-TYPE SERIES OF LEVEL 3 被引量:1
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作者 John M.CAMPBELL 《Acta Mathematica Scientia》 2025年第4期1482-1496,共15页
The level 3 case for Ramanujan-type series has been considered as the most mysterious and the most challenging,out of all possible levels for Ramanujan-type series.This motivates the development of new techniques for ... The level 3 case for Ramanujan-type series has been considered as the most mysterious and the most challenging,out of all possible levels for Ramanujan-type series.This motivates the development of new techniques for constructing Ramanujan-type series of level 3.Chan and Liaw introduced an alternating analogue of the Borwein brothers’identity for Ramanujan-type series of level 3;subsequently,Chan,Liaw,and Tian formulated another proof of the Chan–Liaw identity,via the use of Ramanujan’s class invariant.Using the elliptic lambda function and the elliptic alpha function,we prove,via a limiting case of the Kummer–Goursat transformation,a new identity for evaluating the summands for alternating Ramanujan-type series of level 3,and we apply this new identity to prove three conjectured formulas for quadratic-irrational,Ramanujan-type series that had been discovered via numerical experiments with Maple in 2012 by Aldawoud.We also apply our identity to prove a new Ramanujan-type series of level 3 with a quartic convergence rate and quartic coefficients. 展开更多
关键词 Ramanujan-type series complete elliptic integral modular relation
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Dielectric and Energy Storage Performances of Na_(0.5)Bi_(0.5)TiO_(3)-Based Relaxor Ferroelectric Ceramics
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作者 LI Runzhi SONG Dongpo +4 位作者 GUO Lin YANG Jie ZHANG Yameil YANG Bingbing HUI Zhenzhen 《硅酸盐学报》 北大核心 2025年第12期3720-3728,共9页
Introduction Pure NBT exhibits the frequency-dependent Curie temperature,indicating that its dielectric properties are affected by temperature,measurement frequency,and material processing condition.To enhance the die... Introduction Pure NBT exhibits the frequency-dependent Curie temperature,indicating that its dielectric properties are affected by temperature,measurement frequency,and material processing condition.To enhance the dielectric and relaxor properties of NBT,various dopants such as Sr,K,Li and Bi are incorporated into the NBT structure.These modifications significantly alter the dielectric constant and relaxation behavior,demonstrating a dominant influence of dopant on the material properties.Among these,the solid solution of BaTiO_(3)(BT)with NBT is widely investigated due to its ability to stabilize the perovskite structure and improve dielectric performance.However,the temperature-dependent stability of dielectric properties remains a critical challenge for high-temperature applications.In this study,(1-x)(0.75Na_(0.5)Bi_(0.5)TiO_(3)-0.25BaTiO_(3))-xBaZrO_(3)(NBT-BT-xBZ,x=0,0.08,0.14,and 0.20)ceramics were prepared by a solid-state reaction method.The effect of BaZrO_(3)(BZ)addition on the structural,dielectric,and energy storage properties was systematically investigated.In addition,the phase transition and relaxation behaviors were also analyzed based on the modified Curie-Weiss law,Vogel-Fulcher relation,and Lorentz-type empirical law.Methods The starting materials were powders of high purity Na_(2)CO_(3),Bi_(2)O_(3),TiO_(2),BaCO_(3),and ZrO_(2).The powders were weighed according to a stoichiometric ratio(with 1%excess of Na and Bi)and ground with ethanol in a ball mill at 300 r/min for more than 12 h,and the weight ratio of raw material to ethanol and zirconium balls was 1:1:2.The dried material was heat-treated at 850℃ for 2 h to promote the formation of NBT-BT-BZ.After further grinding for 12 h,the samples were mixed with a small amount of polyvinyl alcohol(PVA).The samples were sintered in air at 1150℃for 2 h and cooled to room temperature.The phase composition of the ceramic samples was determined by an model D8 ADVANDCE X-ray diffractometer(D8 ADVANDCEXRD,Bruker AXS Ltd.,Germany)with Cu target Kαrays,at X-ray wavelengthλof 1.5406Å,2θin the range of 10°to 80°,applied voltage of 40 kV,and a current of 500 mA.A silver paste was coated on the two surfaces as electrodes and heat-treated at 700℃ for 10 min.The dielectric properties of the ceramic samples were determined at different frequencies by a model DMS-1000 high-temperature dielectric temperature spectroscope(BALAB Tech.Co.,China)with at a ramp rate of 3(°)/min in a temperature range from room temperature to 450℃.The overdamped(200Ω)discharge tests for bulk ceramic samples were performed by a model CFD-005 discharge tester(Gogo(GG)Instruments Technology,China)).Results and discussion The XRD patterns indicate that all the ceramic samples have a perovskite structure without any detectable secondary phase,proving that zirconium ions can completely enter the lattice and form a solid solution.Based on the locally magnified XRD peaks,the XRD peak shape shifts towards lower angles as a whole as the BZ content increases.This indicates that the overall volume of the crystal cell shows an expansion as the Zr ions replace Ti ions due to different ionic radii of Zr and Ti ions.The SEM images show that the grain size gradually increases with increasing the BZ content.The addition of BZ promotes the grain growth.However,this gradually slows down with the increase of content up to x of 0.20.The limited grain size variation appears in the latter two samples.All the samples show a relatively dense morphology.The Curie temperature of the NBT-0.25BT ceramic samples is 256℃,which is similar to the reported results.The Curie temperature decreases gradually with the increase of BZ additive,and the dielectric temperature spectrum flattens out,indicating that the enhanced structural and temperature stability of the NBT-BT-BZ ceramics.The maximum values of all dielectric constants correspond to temperatures that increase with frequency,indicating a dielectric relaxor behavior.A frequency dispersion is accompanied at near the Curie temperature,which can be ascribed to the thermal evolution of the tetragonal polar nanoregions(PNRs)and the mixing effect of the transition from tripartite to tetragonal PNRs.Theγvalues obtained from the experimental data at 100 kHz are 1.79,1.83,1.89,and 1.92 for NBT-BT,NBT-BT-0.08BZ,NBT-BT-0.14BZ,and NBT-BT-0.20BZ,respectively.Theγvalue increases gradually with the addition of the BZ content,showing an enhanced relaxation of the NBT-BT-BZ ceramics.The comparison of discharge current curves and energy density of all the ceramics indicate that the addition of BZ significantly improves the discharge current and energy storage performance.A high discharging energy density(Wd)of 1.6 J·cm^(-3) with a fast discharging speed(τ0.9)of 75 ns is obtained for the ceramic samples with x of 0.14.This can be attributed to an increased relaxation as the BZ content increases.Conclusions NBT-BT-BZ ceramics were prepared by a solid-state reaction method.The XRD patterns revealed a phase transition from a tetragonal phase to a pseudocubic phase as the BZ content increased.The dielectric relaxation behavior of the ceramics could be described by three empirical laws(i.e.,modified Curie-Weiss law,Vogel-Fulcher relation and Lorentz-type empirical law).The dielectric relaxation followed the modified Curie-Weiss law and the Vogel-Fulcher relationship.The parametersγand Ea,which were obtained to evaluate the relaxation behavior,increased at a higher BZ content.The Lorentz-type relationship effectively described the temperature dependence of the dielectric constant on both the low-and high-temperature sides within a specific temperature range for all the ceramics. 展开更多
关键词 bismuth sodium titanate energy storage properties relaxation behavior DIELECTRIC Vogel-Fulcher relation
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The Ordering of Unicyclic Graphs with Minimal Matching Energies
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作者 DONG Bo LI Huan WANG Ligong 《数学进展》 北大核心 2025年第5期951-972,共22页
The concept of matching energy was proposed by Gutman and Wagner firstly in 2012. Let G be a simple graph of order n and λ1, λ2, . . . , λn be the zeros of its matching polynomial. The matching energy of a graph G ... The concept of matching energy was proposed by Gutman and Wagner firstly in 2012. Let G be a simple graph of order n and λ1, λ2, . . . , λn be the zeros of its matching polynomial. The matching energy of a graph G is defined as ME(G) = Pni=1 |λi|. By the famous Coulson’s formula, matching energies can also be calculated by an improper integral depending on a parameter. A k-claw attaching graph Gu(k) refers to the graph obtained by attaching k pendent edges to the graph G at the vertex u, where u is called the root of Gu(k). In this paper, we use some theories of mathematical analysis to obtain a new technique to compare the matching energies of two k-claw attaching graphs Gu(k) and Hv(k) with the same order, that is, limk→∞[ME(Gu(k)) − ME(Hv(k))] = ME(G − u) − ME(H − v). By the technique, we finally determine unicyclic graphs of order n with the 9th to 13th minimal matching energies for all n ≥ 58. 展开更多
关键词 matching energy unicyclic graph quasi-order relation k-claw attaching graph
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A close look at few-shot real image super-resolution from the distortion relation perspective
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作者 Xin Li Xin Jin +3 位作者 Jun Fu Xiaoyuan Yu Bei Tong Zhibo Chen 《中国科学技术大学学报》 北大核心 2025年第7期2-13,1,I0001,共14页
Collecting amounts of distorted/clean image pairs in the real world is non-trivial,which severely limits the practical application of these supervised learning-based methods to real-world image super-resolution(RealSR... Collecting amounts of distorted/clean image pairs in the real world is non-trivial,which severely limits the practical application of these supervised learning-based methods to real-world image super-resolution(RealSR).Previous works usually address this problem by leveraging unsupervised learning-based technologies to alleviate the dependency on paired training samples.However,these methods typically suffer from unsatisfactory texture synthesis due to the lack of supervision of clean images.To overcome this problem,we are the first to take a close look at the under-explored direction for RealSR,i.e.,few-shot real-world image super-resolution,which aims to tackle the challenging RealSR problem with few-shot distorted/clean image pairs.Under this brand-new scenario,we propose distortion relation guided transfer learning(DRTL)for the few-shot RealSR by transferring the rich restoration knowledge from auxiliary distortions(i.e.,synthetic distortions)to the target RealSR under the guidance of the distortion relation.Concretely,DRTL builds a knowledge graph to capture the distortion relation between auxiliary distortions and target distortion(i.e.,real distortions in RealSR).Based on the distortion relation,DRTL adopts a gradient reweighting strategy to guide the knowledge transfer process between auxiliary distortions and target distortions.In this way,DRTL is able to quickly learn the most relevant knowledge from the synthetic distortions for the target distortion.We instantiate DRTL with two commonly-used transfer learning paradigms,including pretraining and meta-learning pipelines,to realize a distortion relation-aware few-shot RealSR.Extensive experiments on multiple benchmarks and thorough ablation studies demonstrate the effectiveness of our DRTL. 展开更多
关键词 few-shot RealSR distortion relation graph transfer learning
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A Review of Joint Extraction Techniques for Relational Triples Based on NYT and WebNLG Datasets
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作者 Chenglong Mi Huaibin Qin +1 位作者 Quan Qi Pengxiang Zuo 《Computers, Materials & Continua》 2025年第3期3773-3796,共24页
In recent years,with the rapid development of deep learning technology,relational triplet extraction techniques have also achieved groundbreaking progress.Traditional pipeline models have certain limitations due to er... In recent years,with the rapid development of deep learning technology,relational triplet extraction techniques have also achieved groundbreaking progress.Traditional pipeline models have certain limitations due to error propagation.To overcome the limitations of traditional pipeline models,recent research has focused on jointly modeling the two key subtasks-named entity recognition and relation extraction-within a unified framework.To support future research,this paper provides a comprehensive review of recently published studies in the field of relational triplet extraction.The review examines commonly used public datasets for relational triplet extraction techniques and systematically reviews current mainstream joint extraction methods,including joint decoding methods and parameter sharing methods,with joint decoding methods further divided into table filling,tagging,and sequence-to-sequence approaches.In addition,this paper also conducts small-scale replication experiments on models that have performed well in recent years for each method to verify the reproducibility of the code and to compare the performance of different models under uniform conditions.Each method has its own advantages in terms of model design,task handling,and application scenarios,but also faces challenges such as processing complex sentence structures,cross-sentence relation extraction,and adaptability in low-resource environments.Finally,this paper systematically summarizes each method and discusses the future development prospects of joint extraction of relational triples. 展开更多
关键词 Relation triplet extraction joint extraction methods named entity recognition relation extraction
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Interactions Between Transport,Tourism,and Terrorism in the Context of Globalisation
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作者 Zlatina Karadzhova 《Journalism and Mass Communication》 2025年第2期77-83,共7页
The aim of the study is to explore the essential characteristic of tourism,transport,and terrorism and to highlight the connection between them.Tourism as a phenomenon is related to the question“why do people travel?... The aim of the study is to explore the essential characteristic of tourism,transport,and terrorism and to highlight the connection between them.Tourism as a phenomenon is related to the question“why do people travel?”.The answer to this question requires clarifying a number of sociological and psychological features such as leisure and budget time travel,motivation for travel,psychological benefits,fashion,terrorism,and more.Tourism is a socio-economic and cultural phenomenon that has multiple manifestations.It is one of the factors and driving forces of globalization.Its operation and development leads to the emergence of different economic,socio-cultural,environmental,political,and health effects,making it an indispensable part of modern life. 展开更多
关键词 TOURISM TERRORISM TRANSPORT GLOBALIZATION RELATION
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Strain-manipulated dispersion characteristics of magnonic crystals with Dzyaloshinskii–Moriya interaction and applications on spin-wave devices
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作者 Chuhan Zhou Xiaotian Jiao +3 位作者 Jiaxi Xu Zhaonian Jin Lin Chen Zhikuo Tao 《Chinese Physics B》 2025年第2期431-436,共6页
Dispersion characteristics of magnonic crystals have attracted considerable attention because of the potential applications for spin-wave devices.In this work,we investigated the strain-manipulated dispersion characte... Dispersion characteristics of magnonic crystals have attracted considerable attention because of the potential applications for spin-wave devices.In this work,we investigated the strain-manipulated dispersion characteristics of magnonic crystals with Dzyaloshinskii–Moriya interaction(DMI)and discussed the potential applications in spin-wave devices.Here,the ground states and stabilities of the magnonic crystals were investigated.Then,the strain-manipulated dispersion characteristics of the magnonic crystals based on domains and skyrmions were studied.The simulation results indicated that,the applied strain could manipulate the band widths and the positions of the allowed frequency bands.Finally,the realization of magnonic crystal heterojunctions and potential applications in spin-wave devices,such as filters,diodes,and transistors based on strain-manipulated magnonic crystals were proposed.Our research provides a theoretical foundation for designing tunable spin-wave devices based on strain-manipulated magnonic crystals with DMI. 展开更多
关键词 magnonic crystal spin wave dispersion relation SKYRMION DOMAIN
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Breaking Strength-Ductility Trade-off Relation in Ti-38644 Alloy with Heterogeneous Bi-Grain Bi-Lamella Structure
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作者 Zihao Qiu Chenwei Shao +5 位作者 Shuaijie Han Yang Lu Zhiqin Wang Hanzhong Liu Zhenjun Zhang Zhefeng Zhang 《Acta Metallurgica Sinica(English Letters)》 2025年第8期1312-1316,共5页
Metastable β titanium alloy is an ideal material for lightweight and high strength due to its excellent comprehensive mechanical properties.However,overcoming the trade-off relation between strength and ductility rem... Metastable β titanium alloy is an ideal material for lightweight and high strength due to its excellent comprehensive mechanical properties.However,overcoming the trade-off relation between strength and ductility remains a significant challenge.In this study,the mechanical properties of Ti-38644 alloy were optimized by introducing a heterogeneous bi-grain bi-lamella(BG-BL)structure through a well-designed combination of rolling,drawing and heat treatment.The results demonstrate that the present BG-BL Ti-38644 alloy shows a tensile strength of~1500 MPa and a total elongation of 18%.In particular,the high strength-elongation combination of the BG-BL Ti-38644 alloy breakthroughs the trade-off relation in all the titanium alloys available.The recrystallized grains with low dislocation enhance the ductility of the Ti-38644 alloy,while the highly distorted elongated grains mainly contribute to the high strength.The present study provides a new principle for designing Ti alloys with superior strength and ductility. 展开更多
关键词 Ti alloy Heterogeneous structure Strength DUCTILITY Trade-off relation
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Evaluating the 2024 Hualien,Taiwan,China,tsunami source based on numerical simulations
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作者 Linjian Song Chao An 《Acta Oceanologica Sinica》 2025年第8期66-76,共11页
On April 3,2024,a magnitude Mw 7.4 earthquake struck the city of Hualien,Taiwan,China,causing casualties and immense damage.This earthquake triggered a tsunami,which was recorded by the nearby tide gauges and Deep-Oce... On April 3,2024,a magnitude Mw 7.4 earthquake struck the city of Hualien,Taiwan,China,causing casualties and immense damage.This earthquake triggered a tsunami,which was recorded by the nearby tide gauges and Deep-Ocean Assessment and Reporting of Tsunamis(DART)buoys.These recordings are valuable for evaluating the tsunami source and quantifying the tsunami characteristics.In this study,we conduct tsunami simulations based on three earthquake source models,and analyze their reliability by comparing the computed results with observed waveforms.The evaluated source models are the United States Geological Survey(USGS)finite-fault model,and two uniform slip models using different scaling relations.The tsunami waves generated by each source are simulated with a nonhydrostatic tsunami model,which accounts for the effects of wave dispersion.The computed tsunami arrival times and wave heights are compared to the observed data and show high consistency,indicating that the magnitude and location of the earthquake source are well estimated.Also,the three source models with different rupture area and average slip lead to almost the same tsunami waves at each station,which suggests that earthquake rupture details have limited impact on far-filed tsunami records.It is also found that wave dispersion effects in this event are negligible at most stations.The findings are useful for tsunami warning.For fast warning purposes,it is practically useful to adopt simplified uniform slip models,which are able to predict the tsunami arrival time and wave height relatively well without knowing the earthquake source details. 展开更多
关键词 Hualien earthquake TSUNAMI finite-fault model scaling relation wave dispersion
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Analysis of transverse shear wave in pre-stressed piezoelectric fiber-reinforced composite cylindrical models with non-ideal interface:a comparative study
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作者 Arindam Nath Sanjeev A.Sahu Sudarshan Dhua 《Acta Mechanica Sinica》 2025年第11期148-167,共20页
In the present literature,two types of piezoelectric fiber-reinforced composite(PFRC)based cylindrical models are considered to investigate the circumferential shear wave propagation on a cylinder.Model I consists of ... In the present literature,two types of piezoelectric fiber-reinforced composite(PFRC)based cylindrical models are considered to investigate the circumferential shear wave propagation on a cylinder.Model I consists of a pre-stressed PFRC layer imperfectly bonded to a pre-stressed piezoelectric cylinder of infinite length.Model II comprises a pre-stressed PFRC layer that is imperfectly bonded to a fiber-reinforced core cylinder.The dispersion equations have been derived for both models,assuming electrically open and short boundaries.The numerical simulations are carried out,and results are portrayed graphically to show the effects of various parameters.The radius ratio,pre-stress,mechanical imperfect bonding parameter,fiber reinforcement and fiber-matrix volume ratio exert considerable effects on the PFRC cylinder.Comparative analysis of the dispersion behavior reveals that the shear wave’s phase velocity varies differently for Model I and Model II,and the phase velocity for Model I is higher compared to Model II.The phase velocity reaches its minimum when the piezoelectric fiber is 0.5-0.6 by volume fraction in the PFRC layer. 展开更多
关键词 Shear wave Cylindrical structure PFRC Non-ideal interface Dispersion relation
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The anionic T_(x)defects of Nb_(2)CT_(x)MXene as the effective catalytically active center for the Mg-based hydrogen storage materials
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作者 Xiang Zhou Haotian Guan +6 位作者 Heng Lu Yangfan Lu Jianbo Li Jingfeng Wang Yu'an Chen Qian Li Fusheng Pan 《Journal of Magnesium and Alloys》 2025年第2期571-582,共12页
While early transition metal-based materials,such as MXene,has emerged as an efficient catalyst for the Mg-based hydrogen storage materials,their strong interaction with hydrogen resulted in the high hydrogen diffusio... While early transition metal-based materials,such as MXene,has emerged as an efficient catalyst for the Mg-based hydrogen storage materials,their strong interaction with hydrogen resulted in the high hydrogen diffusion barrier,hindering further improvement of catalytic activity.A MXene is characterized by rich anionic groups on its surface,significantly affecting electronic and catalytic functionalities.Using Nb_(2)CT_(x)as an example,we herein illustrate the critical role of anionic T_(x)defects on controlling hydrogen dissociation and diffusion processes in Mg-based hydrogen storage materials.The hydrogen desorption properties of MgH_(2)can be significantly enhanced by utilizing T_(x)controllable Nb_(2)CT_(x),and it can release 3.57 wt.%hydrogen within 10 min under 240℃with the reduced dehydrogenation activation barrier.It also realized stable de/hydrogenation reactions for at least 50 cycles.DFT studies combined with kinetic analysis revealed that the catalyst‒hydrogen interaction could be systematically controlled by optimizing surface T_(x)defect density,accelerating the hydrogen dissociation and diffusion processes at the same time.These results demonstrate that the T_(x)defects serve as the effective catalytically active centers of Nb_(2)CT_(x),offering a flexible catalyst design guideline. 展开更多
关键词 Mg-based hydrogen storage materials MXene DEFECTS Scaling relation CATALYSIS
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Syntax-Enhanced Entity Relation Extraction with Complex Knowledge
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作者 Mingwen Bi Hefei Chen Zhenghong Yang 《Computers, Materials & Continua》 2025年第4期861-876,共16页
Entity relation extraction,a fundamental and essential task in natural language processing(NLP),has garnered significant attention over an extended period.,aiming to extract the core of semantic knowledge from unstruc... Entity relation extraction,a fundamental and essential task in natural language processing(NLP),has garnered significant attention over an extended period.,aiming to extract the core of semantic knowledge from unstructured text,i.e.,entities and the relations between them.At present,the main dilemma of Chinese entity relation extraction research lies in nested entities,relation overlap,and lack of entity relation interaction.This dilemma is particularly prominent in complex knowledge extraction tasks with high-density knowledge,imprecise syntactic structure,and lack of semantic roles.To address these challenges,this paper presents an innovative“character-level”Chinese part-of-speech(CN-POS)tagging approach and incorporates part-of-speech(POS)information into the pre-trained model,aiming to improve its semantic understanding and syntactic information processing capabilities.Additionally,A relation reference filling mechanism(RF)is proposed to enhance the semantic interaction between relations and entities,utilize relations to guide entity modeling,improve the boundary prediction ability of entity models for nested entity phenomena,and increase the cascading accuracy of entity-relation triples.Meanwhile,the“Queue”sub-task connection strategy is adopted to alleviate triplet cascading errors caused by overlapping relations,and a Syntax-enhanced entity relation extraction model(SE-RE)is constructed.The model showed excellent performance on the self-constructed E-commerce Product Information dataset(EPI)in this article.The results demonstrate that integrating POS enhancement into the pre-trained encoding model significantly boosts the performance of entity relation extraction models compared to baseline methods.Specifically,the F1-score fluctuation in subtasks caused by error accumulation was reduced by 3.21%,while the F1-score for entity-relation triplet extraction improved by 1.91%. 展开更多
关键词 Entity relation extraction complex knowledge syntax-enhanced semantic interaction pre-trained BERT
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Revealing inconsistency of the sediment-water relationships in the Brahmaputra River:A comparative analysis of upstream and downstream cross-sections
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作者 RAHIM Md Abdur LIU Shuang +3 位作者 HU Kaiheng LI Hao ISLAM Maksudul HOSSAIN Sazzad 《Journal of Mountain Science》 2025年第8期2819-2836,共18页
Understanding the relationship between sediment and discharge is crucial for effective river management and water-sediment modeling,especially in the Brahmaputra River,one of the large transboundary rivers with high s... Understanding the relationship between sediment and discharge is crucial for effective river management and water-sediment modeling,especially in the Brahmaputra River,one of the large transboundary rivers with high sediment and discharge variability in South Asia.Current knowledge of sediment-water relations is constrained by limited data,hindering effective transboundary river management.Using multivariate linear regression,climate elasticity coefficient,and traditional sediment rating curve,this study is designed to compare the sediment-water relations of the upstream(Nuxia)and the downstream(Bahadurabad).The results reveal significant variability between the two stations.In the upstream Nuxia,the simulation strongly correlates with observed suspended sediment load(SSL)and discharge(Q)(Pearson's r of 0.62 and 0.68,respectively).Conversely,at downstream Bahadurabad,weaker correlations(r=0.31 for sediment and r=0.51 for discharge simulation)indicate a reduced relation.This contrast reflects the non-linear nature of sediment-discharge coupling along the river continuum,shaped by both climatic and anthropogenic influences.Elasticity(ε)analysis highlights the dominant role of precipitation in shaping sediment-water dynamics(εP-SSL=2.53,εP-Q=1.01)at Nuxia,while Bahadurabad(εP-SSL=0.41,εP-Q=0.82)reflects a reduced sensitivity,possibly due to sediment retention along the floodplain.Air temperature elasticity(εT-SSL,-0.15&-3.06 at Nuxia and Bahadurabad,respectively)reveals contrasting impacts,strongly negatively influencing sediment transport at Bahadurabad.These findings highlight the significance of spatial variability and climatic influences on sediment dynamics,underscoring the necessity for site-specific management strategies.The sediment rating curve(SRC)analysis reveals a strong relationship between sediment and discharge(R^(2)=0.88)at Nuxia and a relatively weaker relationship(R^(2)=0.14)at Bahadurabad,which demonstrates a lower sedimentdischarge coupling that could be affected by downstream factors such as sediment deposition,channel morphology,and anthropogenic activities.This study offers valuable insights into sediment-water dynamics,highlighting the importance of understanding nonlinear relationships in the Brahmaputra River. 展开更多
关键词 Sediment-water relation Climate elasticity Non-linear change Transboundary river The Brahmaputra
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Chinese relation extraction for constructing satellite frequency and orbit knowledge graph:A survey
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作者 Yuanzhi He Zhiqiang Li Zheng Dou 《Digital Communications and Networks》 2025年第5期1305-1317,共13页
As Satellite Frequency and Orbit(SFO)constitute scarce natural resources,constructing a Satellite Frequency and Orbit Knowledge Graph(SFO-KG)becomes crucial for optimizing their utilization.In the process of building ... As Satellite Frequency and Orbit(SFO)constitute scarce natural resources,constructing a Satellite Frequency and Orbit Knowledge Graph(SFO-KG)becomes crucial for optimizing their utilization.In the process of building the SFO-KG from Chinese unstructured data,extracting Chinese entity relations is the fundamental step.Although Relation Extraction(RE)methods in the English field have been extensively studied and developed earlier than their Chinese counterparts,their direct application to Chinese texts faces significant challenges due to linguistic distinctions such as unique grammar,pictographic characters,and prevalent polysemy.The absence of comprehensive reviews on Chinese RE research progress necessitates a systematic investigation.A thorough review of Chinese RE has been conducted from four methodological approaches:pipeline RE,joint entityrelation extraction,open domain RE,and multimodal RE techniques.In addition,we further analyze the essential research infrastructure,including specialized datasets,evaluation benchmarks,and competitions within Chinese RE research.Finally,the current research challenges and development trends in the field of Chinese RE were summarized and analyzed from the perspectives of ecological construction methods for datasets,open domain RE,N-ary RE,and RE based on large language models.This comprehensive review aims to facilitate SFO-KG construction and its practical applications in SFO resource management. 展开更多
关键词 Relation extraction Information extraction Distant supervision Parsing tree Joint entity-relation extraction
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Anisotropic strength and deformation of irregular columnar jointed rock masses under triaxial stress
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作者 QUE Xiang-cheng ZHU Zhen-de +1 位作者 NIU Zi-hao ZHU Shu 《Journal of Central South University》 2025年第2期643-655,共13页
The special columnar jointed structure endows rocks with significant anisotropy,accurately grasping the strength and deformation properties of a columnar jointed rock mass(CJRM)under complex geological conditions is c... The special columnar jointed structure endows rocks with significant anisotropy,accurately grasping the strength and deformation properties of a columnar jointed rock mass(CJRM)under complex geological conditions is crucial for related engineering safety.Combined with the irregular jointed networks observed in the field,artificial irregular CJRM(ICJRM)samples with various inclination angles were prepared for triaxial tests.The results showed that the increase in confining pressure can enhance the ability of the ICJRM to resist deformation and failure,and reduce the deformation and strength anisotropic degrees.Considering the field stress situation,the engineering parts with an inclination angle of 30°−45°need to be taken seriously.Four typical failure modes were identified,and the sample with an inclination angle of 15°showed the same failure behavior as the field CJRM.Traditional and improved joint factor methods were used to establish empirical relationships for predicting the strength and deformation of CJRM under triaxial stress.Since the improved joint factor method can reflect the unique structure of CJRM,the predictive ability of the empirical relationship based on the improved method is better than that based on the traditional joint factor method. 展开更多
关键词 irregular columnar jointed rock mass triaxial stress STRENGTH DEFORMATION anisotropic mechanical property empirical relation
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