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Accuracy of forecast of mine tremors location

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Mining Science and Technology 2009年第5期19卷 668-673页

作者： DRZEWIECKI jan Central Mining Institute

The Upper Silesian Coal Basin is one of the most active mining areas in the world in respect of seismicity. Underground mining in this area takes place in a special environment with a high degree of risk of unpredictable event occurrence. Especially dangerous are phenomena that occur during the extraction of deposits at great depths in the environment of compact rocks. Deep underground mining violates the balance of these rocks and induces dynamic phenomena at the longwall life （in terms of distance） referred to as mine tremors. The sources of these tremors are located in layers characterised by high strength, especially in thick sandstone strata occurring in the roof of the mined seam. In the paper a discussion is presented about the influence of mining intensity （longwall face speed） on the location of mine tremor sources, both in the direction of longwall life （in terms of distance） and towards the surface. The presented material has been prepared basing on the results of tests and measurements carded out at the Central Mining Institute.

关键词： mine tremors forecast longwall life

Utilization of fly ash from coal-fired power plants in China

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第5期9卷 681-687页

作者： Eva SELIC jan-Dirk HERBELL Waste Management Engineering Department of Mechanical Engineering University of Duisburg-Essen Duisburg 47057 Germany

The rapidly increasing demand for energy in China leads to the construction of new power plants all over the country. Coal, as the main fuel resource of those power plants, results in increasing problems with the disposal of solid residues from combustion and off gas cleaning. This investigation describes chances for the utilization of fly ash from coal-fired power plants in China. After briefly comparing the situation in China and Germany, the status of aluminum recycling from fly ash and the ad- vantages for using fly ash in concrete products are introduced. Chemical and physical analyses of Chinese fly ash samples, e.g., X-ray diffraction (XRD), ICP (Inductive Coupled Plasma) and particle size analysis, water requirement, etc. are presented. Rea- sonable amounts of aluminum were detected in the samples under investigation, but for recovery only sophisticated procedures are available up to now. Therefore, simpler techniques are suggested for the first steps in the utilization of Chinese fly ash.

关键词： Fly ash utilization Aluminum recycling Concrete Chemical and physical analyses

Hybrid In-Vehicle Background Noise Reduction for Robust Speech Recognition:The Possibilities of Next Generation 5G Data Networks

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Computers, Materials & Continua 2022年第6期71卷 4659-4676页

作者： Radek Martinek jan Baros Rene Jaros Lukas Danys jan Nedoma VSB-Technical University of Ostrava Faculty of Electrical Engineering and Computer ScienceDepartment of Cybernetics and Biomedical Engineering70800Ostrava-PorubaCzechia VSB Technical University of Ostrava Faculty of Electrical Engineering and Computer ScienceDepartment of Telecommunications70800Ostrava-PorubaCzechia

This pilot study focuses on employment of hybrid LMS-ICA system for in-vehicle background noise *** vehicles are nowadays increasingly supporting voice commands,which are one of the pillars of autonomous and SMART *** speaker recognition for context-aware in-vehicle applications is limited to a certain extent by in-vehicle back-ground *** article presents the new concept of a hybrid system which is implemented as a virtual *** highly modular concept of the virtual car used in combination with real recordings of various driving scenarios enables effective testing of the investigated methods of in-vehicle background noise *** study also presents a unique concept of an adaptive system using intelligent clusters of distributed next generation 5G data networks,which allows the exchange of interference information and/or optimal hybrid algorithm settings between individual *** average,the unfiltered voice commands were successfully recognized in 29.34%of all scenarios,while the LMS reached up to 71.81%,and LMS-ICA hybrid improved the performance further to 73.03%.

关键词： 5G noise reduction hybrid algorithms speech recognition 5G data networks in-vehicle background noise

原特提斯洋俯冲起始——来自北祁连早寒武世弧前岩浆作用的新证据

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岩石矿物学杂志 2024年第2期43卷 250-273页

作者：张同悦张建新于胜尧祁钰李传志中国海洋大学海底科学与探测技术教育部重点实验室山东青岛266100 中国地质科学院地质研究所北京100037 崂山国家实验室海洋矿产资源评价与探测技术功能实验室山东青岛266237

形成于弧前背景的岩浆岩可能记录了俯冲起始的重要证据。本文以北祁连走廊南山蛇绿混杂岩带新识别出的富铌辉长岩和斜长花岗岩为研究对象,在野外观察的基础上,结合岩石学、地球化学、同位素地球化学和年代学的综合研究,对原特提斯洋初... 详细信息

形成于弧前背景的岩浆岩可能记录了俯冲起始的重要证据。本文以北祁连走廊南山蛇绿混杂岩带新识别出的富铌辉长岩和斜长花岗岩为研究对象,在野外观察的基础上,结合岩石学、地球化学、同位素地球化学和年代学的综合研究,对原特提斯洋初始俯冲的时间进行约束,并探讨其形成过程及构造意义。锆石U-Pb定年结果显示富铌辉长岩样品锆石加权平均^(206)Pb/^(238)U年龄为512±4 Ma;两个斜长花岗岩样品的锆石加权平均^(206)Pb/^(238)U年龄分别为522±3 Ma和519±1 Ma。全岩地球化学结果显示富铌辉长岩的Nb含量为7.49×10^(-6)~10.80×10^(-6),TiO_(2)含量为1.50%~2.08%,Nb/U值为11.9~13.4,(Nb/La)N>0.5,明显高于岛弧玄武岩,其εNd(t)值介于+4.38~+5.78之间。斜长花岗岩样品K_(2)O含量(0.31%~1.66%)和K_(2)O/Na2O值(0.05~0.43)较低,稀土元素分布模式较为平缓,具有轻微的Eu正或负异常,相对富集Ba、Sr、U等大离子亲石元素,亏损Nb、Ta等高场强元素,结合其正的εNd(t)值(+3.35)和高、正的锆石εHf(t)值(主要在6.2~12.9之间),类似于弧前大洋斜长花岗岩。综合这些研究资料和区域地质,我们认为百经寺斜长花岗岩可能形成于俯冲初始阶段高温环境下俯冲洋壳部分熔融,随着俯冲继续,俯冲板片在更深部的部分熔融形成埃达克质熔体,并交代地幔楔形成富铌辉长岩。这些研究资料表明北祁连所代表的原特提斯洋的初始俯冲发生在早寒武世。

关键词：初始俯冲富铌辉长岩斜长花岗岩北祁连原特提斯洋

Evaluation of overhead line current unbalance in meshed grids and its reduction

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Journal of Modern Power Systems and Clean Energy 2018年第6期6卷 1204-1212页

作者： Jakub EHRENBERGER jan ?VEC Department of Electrical Power Engineering Czech Technical University in Prague

This paper describes new methodology in the current unbalance calculations in meshed grids. The meshed grids, mainly the transmission ones, consist of more parts connected together which are formed using different conductor types, phase sequence arrangements,tower constructions, and various number of lines on the same tower. Therefore several computational challenges arise in comparison with the widely discussed point-topoint configuration. The methodology divides the grid into a number of impedance matrices respecting all the self and mutual impedances among all conductors and all parallel lines. Another challenging issue for the line impedancedescription is changing the number of shield wires along the line if the line is composed of several sections with different tower configurations. For the current unbalance calculation, shield wires must also be included in the algorithms, and matrices of various dimensions can be obtained. For the overall matrix description to be used,dimensions of all matrices in final equations must be equal,and therefore the virtual shield wires are created. To compare more conductor transposition cases with each other, the line loadings caused by voltage sources should be equal. This is necessary mainly in case of meshed grids where the supplying sources on different lines can have strong mutual couplings. This can be achieved by an appropriately designed optimization of the connected voltage sources.

关键词： Current unbalance Phase sequence arrangement Shield wire Unbalance factor Zero-sequence set

Grobner-Shirshov Bases for Plactic Algebras

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Algebra Colloquium 2014年第4期21卷 591-596页

作者： Lukasz Kubat jan Oknifiski Institute of Mathematics Polish Academy of Sciences Sniadeckich 8 00-956 Warsaw Poland Institute of Mathematics Warsaw University Banacha 2 02-097 Warsaw Poland

A finite GrSbner-Shirshov basis is constructed for the plactic algebra of rank 3 over a field K. It is also shown that plactic algebras of rank exceeding 3 do not have finite GrSbner-Shirshov bases associated to the natural degree-lexicographic ordering on the corresponding free algebra. The latter is in contrast with the case of a strongly related class of algebras, called Chinese algebras.

关键词： plactic monoid GrSbner-Shirshov basis semigroup algebra

Gene Networks in Plant Ozone Stress Response and Tolerance

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Journal of Integrative Plant Biology 2008年第10期50卷 1256-1267页

作者： Agnieszka Ludwikow jan Sadowski Department of Biotechnology Institute of Molecular Biology and Biotechnology Faculty of Biology Adam Mickiewicz University Miedzychodzka 5 60-371 Poznan Poland Institute of Plant Genetics Polish Academy of Sciences Strzeszynska 34 60-479 Poznan Poland

For many plant species ozone stress has become much more severe in the last decade. The accumulating evidence for the significant effects of ozone pollutant on crop and forest yield situate ozone as one of the most important environmental stress factors that limits plant productivity worldwide. Today, transcriptomic approaches seem to give the best coverage of genome level responses. Therefore, microarray serves as an invaluable tool for global gene expression analyses, unravelling new information about gene pathways, in-species and cross-species gene expression comparison, and for the characterization of unknown relationships between genes. In this review we summarize the recent progress in the transcriptomics of ozone to demonstrate the benefits that can be harvested from the application of integrative and systematic analytical approaches to study ozone stress response. We focused our consideration on microarray analyses identifying gene networks responsible for response and tolerance to elevated ozone concentration. From these analyses it is now possible to notice how plant ozone defense responses depend on the interplay between many complex signaling pathways and metabolite signals.

关键词： crosstalk interactions gene network microarray ozone stress signaling.

Teleconnections of Inter-Annual Streamflow Fluctuation in Slovakia with Arctic Oscillation,North Atlantic Oscillation,Southern Oscillation,and Quasi-Biennial Oscillation Phenomena

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Advances in Atmospheric Sciences 2007年第4期24卷 655-663页

作者： pavla PEKAROVA jan PEKAR Institute of Hydrology Slovak Academy of SciencesRacianska 75831 02 Bratislava 3Slovak Republic Department of Applied Mathematics and Statistics Faculty of MathematicsPhysics and InformaticsComenius University BratislavaMlynska dolina842 48 BratislavaSlovak Republic

The aim of the paper is to analyze a possible teleconnection of Quasi-Biennial Oscillation （QBO）, Southern Oscillation （SO）, North Atlantic Oscillation （NAO）, and Arctic Oscillation （AO） phenomena with longterm streamflow fluctuation of the Bela River （1895-2004） and Cierny Hron River （1931-2004）（central Slovakia）. Homogeneity, long-term trends, as well as inter-annual dry and wet cycles were analyzed for the entire 1895-2004 time series of the Bela River and for the 1931-2004 time series of the Cierny Hron River. Inter-annual fluctuation of the wet and dry periods was identified using spectral analysis. The most significant period is that of 3.6 years. Other significant periods are those of 2.35 years, 13.5 years, and 21 years. Since these periods were found in other rivers of the world, as well as in SO, NAO, and AO phenomena, they can be considered as relating to the general regularity of the Earth.

关键词： inter-annual discharge fluctuation spectral analysis teleconnection Quasi-Biennial Oscillation Southern Oscillation North Atlantic Oscillation Arctic Oscillation

Reconstruction of paleocoastlines for the northwestern South China Sea since the Last Glacial Maximum

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Science China Earth Sciences 2009年第8期52卷 1127-1136页

作者： HARFF jan MEYER Michael Leibniz Institute for Baltic Sea Research Warnemünde

The range of relative sea level rise in the northwestern South China Sea since the Last Glacial Maximum was over 100 m. As a result, lowland regions including the Northeast Vietnam coast, Beibu Gulf, and South China coast experienced an evolution from land to sea. Based on the principle of reconstructing paleogeography and using recent digital elevation model, relative sea level curves, and sediment accumulation data, this paper presents a series of paleogeographic scenarios back to 20 cal. ka BP for the northwestern South China Sea. The scenarios demonstrate the entire process of coastline changes for the area of interest. During the late glacial period from 20 to 15 cal. ka BP, coastline slowly retreated, causing a land loss of only 1×104 km2, and thus the land-sea distribution remained nearly unchanged. Later in 15-10 cal. ka BP coastline rapidly retreated and area of land loss was up to 24×104 km2, causing lowlands around Northeast Vietnam and South China soon to be underwater. Coastline retreat continued quite rapidly during the early Holocene. From 10 to 6 cal. ka BP land area had decreased by 9×104 km2, and during that process the Qiongzhou Strait completely opened up. Since the mid Holocene, main controls on coastline change are from vertical crustal movements and sedimentation. Transgression was surpassed by regression, resulting in a land accretion of about 10×104 km2.

关键词： relative sea level change paleocoastline reconstruction Last Glacial Maximum northwestern South China Sea