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Seismogenic ULF/ELF Wave Phenomena: Recent Advances and Future Perspectives

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Open Journal of Earthquake Research 2023年第3期12卷 45-113页

作者： Masashi Hayakawa Alexander Schekotov jun izutsu Alexander P. Nickolaenko Yasuhide Hobara Hayakawa Institute of Seismo Electromagnetics Co. Ltd. (Hi-SEM) UEC Alliance Center #521 Tokyo Japan The University of Electro-Communications (UEC) Advanced & Wireless Communications Research Center (AWCC) Tokyo Japan Institute of Physics of the Earth Russian Academy of Sciences Moscow Russia Chubu University International Digital Earth Applied Science Research Center Kasugai Aichi Japan Usikov Institute for Radio-Physics and Electronics National Academy of Sciences of the Ukraine Kharkov Ukraine UEC Graduate School of Informatics and Engineering Tokyo Japan

There has been enormous progress in the field of electromagnetic phenomena associated with earthquakes (EQs) and EQ prediction during the last three decades, and it is recently agreed that electromagnetic effects do appear prior to an EQ. A few phenomena are well recognized as being statistically correlated with EQs as promising candidates for short-term EQ predictors: the first is ionospheric perturbation not only in the lower ionosphere as seen by subionospheric VLF (very low frequency, 3 kHz f 30 kHz)/LF (low frequency, 30 kHz f 300 kHz) propagation but also in the upper F region as detected by ionosondes, TEC (total electron content) observations, satellite observations, etc, and the second is DC earth current known as SES (Seismic electric signal). In addition to the above two physical phenomena, this review highlights the following four physical wave phenomena in ULF (ultra low frequency, frequency Hz)/ELF (extremely low frequency, 3 Hz frequency 3 kHz) ranges, including 1) ULF lithospheric radiation (i.e., direct radiation from the lithosphere), 2) ULF magnetic field depression effect (as an indicator of lower ionospheric perturbation), 3) ULF/ELF electromagnetic radiation (radiation in the atmosphere), and 4) Schumann resonance (SR) anomalies (as an indicator of the perturbations in the lower ionosphere and stratosphere). For each physical item, we will repeat the essential points and also discuss recent advances and future perspectives. For the purpose of future real EQ prediction practice, we pay attention to the statistical correlation of each phenomenon with EQs, and its predictability in terms of probability gain. Of course, all of those effects are recommended as plausible candidates for short-term EQ prediction, and they can be physically explained in terms of the unified concept of the lithosphere-atmosphere-ionosphere coupling (LAIC) process, so a brief description of this coupling has been carried out by using these four physical parameters though

关键词： ULF/ELF Seismogenic Wave Effects Statistical Significance Lithosphere-Atmosphere-Ionosphere Coupling

On the Precursory Abnormal Animal Behavior and Electromagnetic Effects for the Kobe Earthquake (M~6) on April 12, 2013

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Open Journal of Earthquake Research 2016年第3期5卷 165-171页

作者： Masashi Hayakawa Hiroyuki Yamauchi Nobuyo Ohtani Mitsuaki Ohta Susumu Tosa Tomokazu Asano Alexander Schekotov jun izutsu Stelios M. Potirakis Konstantinos Eftaxias Hayakawa Institute of Seismo Electromagnetics Co. Ltd. UEC (University of Electro-Communications) Incubation Center Chofu Japan UEC Advanced Wireless & Communications Research Center Chofu Japan Department of Animal Science and Biotechnology Azabu University Sagamihara Japan Department of Human and Animal-Plant Relationships Tokyo University of Agriculture Atsugi Japan Kagawa Prefecture Livestock Experiment Station Kida Japan Institute of Physics of the Earth Russian Academy of Sciences Moscow Russia Department of Electronic Engineering Chubu University Kasugai Japan Department of Electronics Engineering Piraeus University of Applied Sciences (TEI of Piraeus) Athens Greece Department of Physics University of Athens Athens Greece

After the 2011 Tohoku earthquake (EQ), there have been numerous aftershocks in the eastern and Pacific Ocean of Japan, but EQs are still rare in the western part of Japan. In this situation a relatively large (magnitude (M) ~6) EQ happened on April 12 (UT), 2013 at a place close to the former 1995 Kobe EQ (M~7), so we have tried to find whether there existed any precursors to this EQ, especially abnormal animal behavior (milk yield of cows), observed at Kagawa, Shikoku, near the EQ epicenter. The milk yield of cows has been continuously monitored at Kagawa, and it is found that the milk yield exhibited an abnormal depletion about 10 days before the EQ. This behavior has been extensively compared with the former electromagnetic precursors (ULF radiation, ionos-pheric perturbation). This leads to the discussion on the sensory mechanism of unusual behavior of mild yield of cows, and it may be suggested that ULF radiation among different electromagnetic precursors is a mostly likely driver, at least, for this EQ.

关键词： Abnormal Animal Behavior Earthquakes Milk Yield of Cows ULF Radiation Sensory Mechanism of Animals

Key issues on magnetic reconnection at Mercury

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Earth and Planetary Physics 2024年第5期8卷 673-685页

作者： jun Zhong Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences

Magnetic reconnection processes and their impact on planetary magnetospheric dynamics exhibit significant differences due to differences in upstream solar wind conditions and internal planetary environments. Current understanding of reconnection phenomena at Mercury is rooted in the MESSENGER mission. However, direct detection of reconnection remains rare. Here, we aim to assess the limitations of MESSENGER in detecting reconnection in Mercury's space and to discuss key issues of reconnection that will be addressed by BepiColombo, including the dynamics of magnetic flux ropes, particle acceleration, density asymmetric reconnection,IMF-driven near-tail structures, and potential modes of magnetospheric convection.

关键词： magnetic reconnection Mercury MESSENGER BepiColombo

Numerical investigation of non-uniform temperature fields for proppant and fluid phases in supercritical CO_(2)fracturing

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Particuology 2024年第7期90卷 149-163页

作者： Boyu Liu jun Yao Research Center of Multiphase Flow in Porous Media China University of Petroleum(East China)Qingdao 266000China

The non-uniform temperature distribution in supercritical CO_(2)(Sc-CO_(2))fracturing influences the density,viscosity,and volume expansion or shrinkage rate of Sc-CO_(2),impacting proppant *** study presents a coupled computational fluid dynamics-discrete element method and heat transfer model to examine the effects of proppant bed shape and the heat transfers of proppant-wall,proppant-fluid,and fluid-wall on the fluid and proppant temperature *** Sc-CO_(2)volume expansion is assessed under various temperature conditions by evaluating the volume-averaged Sc-CO_(2)*** factors,including proppant size,shape,thermal conductivity,concentration,temperature difference,and injection velocity,are carefully analyzed to elucidate their *** findings elucidate the existence of four distinct zones in the fluid temperature *** zone exhibits different magnitudes of temperature change under diverse conditions and undergoes dynamic transformations with the development of the proppant *** fluid-wall heat transfer and the fluid temperatures in Zones C and D are significantly subject to the fluid injection velocity(governing the heating duration),the temperature difference between fluid and formation(impacting the magnitude of heat flux),and the proppant bed shape(controlling the effective heating area).Additionally,the proppant-wall and proppant-fluid heat transfers determine the temperatures of both the proppant bed and the fluid within Zone B,showing a strong correlation with proppant thermal conductivity,proppant size,injection velocity,and temperature *** proposed coupled model provides valuable insights into the temperature distributions and flow behaviors of temperature-dependent fracturing fluids and proppants.

关键词： CFD-DEM Heat transfer Compressible fluid CO_(2)sequestration Proppant transport

Geometric Error Identification of Gantry-Type CNC Machine Tool Based on Multi-Station Synchronization Laser Tracers

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 150-162页

作者： jun Zha Huijie Zhang School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China Xi’an Jiaotong University Suzhou Academy Suzhou 215123China

Laser tracers are a three-dimensional coordinate measurement system that are widely used in industrial *** propose a geometric error identification method based on multi-station synchronization laser tracers to enable the rapid and high-precision measurement of geometric errors for gantry-type computer numerical control(CNC)machine *** method also improves on the existing measurement efficiency issues in the single-base station measurement method and multi-base station time-sharing measurement *** consider a three-axis gantry-type CNC machine tool,and the geometric error mathematical model is derived and established based on the combination of screw theory and a topological analysis of the machine kinematic *** four-station laser tracers position and measurement points are realized based on the multi-point positioning principle.A self-calibration algorithm is proposed for the coordinate calibration process of a laser tracer using the Levenberg-Marquardt nonlinear least squares method,and the geometric error is solved using Taylor’s first-order linearization *** experimental results show that the geometric error calculated based on this modeling method is comparable to the results from the Etalon laser *** a volume of 800 mm×1000 mm×350 mm,the maximum differences of the linear,angular,and spatial position errors were 2.0μm,2.7μrad,and 12.0μm,respectively,which verifies the accuracy of the proposed *** research proposes a modeling method for the precise measurement of errors in machine tools,and the applied nature of this study also makes it relevant both to researchers and those in the industrial sector.

关键词： Multi-point positioning Multi-station synchronization CNC machine tool Geometric error Error separation

A generalized presentation of multi-caloric effects based on exterior derivative theory and its applications

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Communications in Theoretical Physics 2024年第8期76卷 156-163页

作者： jun Yin School of Materials Science and Engineering Nankai UniversityTianjin 300350China School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350108China

The emerging concept of multi-caloric effects, introduced in 2010, entails the application of multiple interplay fields to a thermodynamic system. While multi-caloric effects are the main focus of experimental endeavors, theoretical considerations fall short of providing a thorough understanding. This paper introduces a comprehensive presentation on multi-caloric effects,employing the method and theory of exterior derivative formations. It addresses every aspect of thermodynamic systems, showcasing its applicability to multi-caloric materials(both singlephase and multi-phase materials), and its adaptability to different scenarios(either in single or multiple force fields). The formulation of Maxwell relationships, characterized by their generality and universality, enables a clear prediction in entropy and temperature, facilitating a distinct identification between independent and interdependent contributions from multi-caloric effects. These insights hold significant importance in designing and developing specialized thermodynamic materials, optimizing functional performances and exploring innovative mechanisms.

关键词： multicaloric effects Maxwell relations isothermal entropy adiabatic temperature

On the Monge–Kantorovich Mass Transfer Problem in Higher Dimensions

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1989-2004页

作者： Xiao jun LU School of Mathematics Southeast UniversityNanjing 210096P.R.China

This paper mainly investigates the approximation of a global maximizer of the Monge–Kantorovich mass transfer problem in higher dimensions through the approach of nonlinear partial differential equations with Dirichlet *** an approximation mechanism,the primal maximization problem can be transformed into a sequence of minimization *** applying the systematic canonical duality theory,one is able to derive a sequence of analytic solutions for the minimization *** the final analysis,the convergence of the sequence to an analytical global maximizer of the primal Monge–Kantorovich problem will be demonstrated.

关键词： Monge-Kantorovich mass transfer singular variational problem canonical duality theory

Low-protein diet supplemented with 1% L-glutamine improves growth performance, serum biochemistry, redox status, plasma amino acids, and alters fecal microbiota in weaned piglets

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Animal Nutrition 2024年第2期17卷 144-154页

作者： jun Li jun Bai Ying Yang Zhenlong Wu State Key Laboratory of Animal Nutrition and Feeding Department of Companion Animal Science China Agricultural University

Glutamine, one of the most abundant amino acids in the body, has been shown to exert various beneficial effects in pigs. However, knowledge regarding the role of dietary glutamine in low-protein diet-fed piglets remains scarce. The present study aimed to investigate the effects of different levels of L-glutamine on growth performance, serum biochemistry parameters, redox status, amino acids, and fecal microbiota in low-protein diet-fed piglets. A total of 128 healthy crossbred piglets(Landrace × Yorkshire)were randomly allocated into 4 groups of 4 replicate pens, with 8 piglets per pen. Piglets in the 4 groups were fed with corn and soybean meal-based low-protein diets(crude protein level, 17%) that contained0%, 1%, 2%, and 3% L-glutamine, respectively, for 28 d. Pigs administered 1% L-glutamine had greater body weight on d 28 and average daily gain(ADG, P < 0.01), whereas a lower feed to gain ratio(F:G) from d 1to 28(P < 0.01), compared to the other three groups. Besides, lower body weight on d 14 and 28, ADG,average daily feed intake, and higher F:G from d 15 to 28 and d 1 to 28 were observed in response to 2%and 3% L-glutamine treatments than 0% and 1% L-glutamine treatments(P < 0.01). Moreover, 1% Lglutamine reduced serum glucose, malondialdehyde, hydrogen peroxide concentrations and inhibited aspartate aminotransferase, alanine aminotransferase, myeloperoxidase activities in low-protein diet-fed piglets on d 14, with concomitantly upregulated catalase, total superoxide dismutase activities and glutathione level(P < 0.05). However, dietary 3% L-glutamine enhanced blood urea nitrogen content in pigs on d 14(P < 0.05). Further investigation revealed that 1% L-glutamine upregulated the serum glutamine, lysine, methionine, tyrosine, and reduced plasma valine content(P < 0.05). Additionally, 1% Lglutamine upregulated the abundance of p＿75＿a5, Clostridium, Lactobacillus, Prevotellaceae＿Prevotella,and Gemmiger in the stool of piglets on d 14, with the Streptococcus lev

关键词： Glutamine Low protein diet Pig Redox status Amino acid Microbiota

Effect of Wave Nonlinearity on the Instantaneous Seabed Liquefaction

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China Ocean Engineering 2024年第1期38卷 93-103页

作者： WANG Zhao-jun SUI Ti-ti ZHANG Chi PAN jun-ning Key Laboratory of Port Waterway and Sedimentation Engineering of the Ministry of TransportNanjing Hydraulic Research InstituteNanjing 210024China Key Laboratory of Coastal Disaster and Protection(Hohai University) Ministry of EducationNanjing 210098China The National Key Laboratory of Water Disaster Prevention Nanjing 210098China

The nonlinear variation of wave is commonly seen in nearshore area,and the resulting seabed response and liquefaction are of high concern to coastal *** this study,an analytical formula considering the nonlinear wave skewness and asymmetry is adopted to provide wave pressure on the seabed *** liquefaction depth attenuation coefficient and width growth coefficient are defined to quantitatively characterize the nonlinear effect of wave on seabed *** on the 2D full dynamic model of wave-induced seabed response,a detailed parametric study is carried out in order to evaluate the influence of the nonlinear variation of wave loadings on seabed ***,new empirical prediction formulas are proposed to fast predict the maximum liquefaction under nonlinear *** indicate that(1)Due to the influence of wave nonlinearity,the vertical transmission of negative pore water pressure in the seabed is hindered,and therefore,the amplitude decreases significantly.(2)In general,with the increase of wave nonlinearity,the liquefaction depth of seabed decreases *** under asymmetric and skewed wave loading,the attenuation of maximum seabed liquefaction depth is the most significant among all the nonlinear wave ***,highly skewed wave can cause the liquefaction depth of seabed greater than that under linear wave.(3)The asymmetry of wave pressure leads to the increase of liquefaction width,whereas the influence of skewedness is not significant.(4)Compared with the nonlinear waveform,seabed liquefaction is more sensitive to the variation of nonlinear degree of wave loading.

关键词： nonlinear wave seabed response seabed liquefaction numerical simulation liquefaction prediction