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Flat solutions of some Non-Lipschitz Autonomous semilinear Equations May be stable for N≥3

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Chinese Annals of Mathematics,series B 2017年第1期38卷 345-378页

作者： Jesús Ildefonso DIAZ Jesús HERNaNDEZ Yavdat IL'Y AsOV Instituto de Matematica Interdisciplinar Universidad Complutense de Madrid 28040 MadridSpain. Departamento de Matematicas Universidad Autonoma de Madrid 28049 CantoblancoMadridSpain. Institute of Mathematics Ufa Science Center of RAS 112Chernyshevsky StrUfa 450077Russia.

The authors prove that flat ground state solutions(i.e. minimizing the energy and with gradient vanishing on the boundary of the domain) of the Dirichlet problem associated to some semilinear autonomous elliptic equations with a strong absorption term given by a non-Lipschitz function are unstable for dimensions N = 1, 2 and they can be stable for N ≥ 3 for suitable values of the involved exponents.

关键词： semilinear elliptic and parabolic equation strong absorption spectral problem Nehari manifolds Pohozaev identity Flat solution Linearized stability Lyapunov function Global instability

Assessing silicon Availability in soils of Rice-Growing Lowlands and Neighboring Uplands in Benin and Nigeria

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Rice science 2016年第4期23卷 196-202页

作者： s. s. ABE Y. YAMAsAkI T. WAkATsUkI Africa Rice Center 01 BP2031 Cotonou Benin Faculty of Agriculture Kinki University Nara 631-8505 Japan Faculty of Life and Environmental science Shimane University Matsue 690-8504 Japan

silicon(si) is known as a beneficial nutrient in the cultivation of rice, playing a key role in photosynthesis enhancement, lodging resistance and tolerance to various environmental stress. The present study aimed to examine available si content in both lowland soils(n = 29) and neighboring upland soils(n = 21) collected from Benin and Nigeria and to evaluate the validity of the assessment results through a pot experiment. Our results revealed that the acetate-buffer method predicted si concentration in rice straw at the harvest stage(R^2 = 0.68, P 0.05), and 76% of the uplands and 38% of the lowlands were deficient(kg) in acetate-buffer soluble si. These findings suggest that the si-deficiency soils prevail across the study area, making rice plants starved for si and prone to environmental stress.

关键词： Oryza sativa silicon upland field lowland field

secret key Optimization for secure speech Communications

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Computers, Materials & Continua 2022年第8期72卷 3025-3037页

作者： Osama s.Faragallah Mahmoud Farouk Hala s.El-sayed Department of Information Technology College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Department of Computer science and Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf 32952Egypt Department of Electrical Engineering Faculty of EngineeringMenoufia UniversityShebin El-Kom 32511Egypt

This paper answers three essential questions for audio speech cryptosystems in time and discrete transform *** first question is,what are the best values of sub-keys that must be used to get the best quality and security for the audio cryptosystem in time and discrete transform *** second question is the relation between the number of sub-keys,the number of secret keys used,and the audio speech signal block’s ***,how many possible secret keys can be used to get the best quality and security results for the audio speech cryptosystem in time and discrete transform *** audio cryptosystem discussed before in recent research is applied to answer the three previous *** simulation results and analysis answer all three questions;first,there is no specific,well-defined format or rule for sub-key values that must be used to get a better *** the second question,yes,there is a direct relationship between the number of applicable keys,number of available sub-keys,and block size of speech audio signal and formulated into a first-order *** the third question,each discrete transform domain has a specific acceptable range of sub-keys that imply a particular number of keys that can be used to get a better cryptosystem.

关键词： Audio cryptosystem chaotic baker map secret key size

Characterization and separation of pyrite from Abu Tartur black shale

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International Journal of Mining science and Technology 2015年第4期25卷 565-571页

作者： Ibrahim s.s. El kammar A.M. Guda A.M. Central Metallurgical R&D Institute CMRDI Geology Dept. Faculty of Science National Research Astronomical & Geophysical Institute NRIAG

This work aimed for pyrite separation from Abu Tartur black shale as a source of sulfur to be an added economic value of Abu Tartur area. The considered samples in the present work were collected from a core drilled in Abu Tartur plateau representing the pyrite-rich black shale of the U. Cretaceous age, sample characterization was carried out using petrographic microscope, XRD, DTA/DTG, C/s and XRF techniques. Clay minerals, silt-sized quartz, calcite, and hematite were the main minerals associating pyr- ite （5.34g）. Liberation behavior of the sample was about 80% below 5 μm. sample processing was achieved through one-day soaking followed by classification using I inch Mozley hydro-cyclone where about 35.5% by weight went to underflow and 64.5% went to overflow. The underflow product was subjected to an advanced gravity separation process using sB-40 Falcon Concentrator through a CCD statistical design prepared by Design-Expert 6.0 software proposed to opti- mize the separation process through a study for the effects of frequency （Hz） and water pressure （Psi） on both assay and recovery of the sulfur-rich heavy fraction. A heavy concentrate weighed 10.90% with inorganic sulfur content reached 11.37% （21.24% pyrite） with overall recovery （50.01%） was obtained after two cleaning at the optimum conditions.

关键词： Abu Tartur plateau Black shale Pyrite Falcon Concentrator

A study of spot Welding of Advanced High strength steels for Automotive Applications

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Journal of Iron and steel Research International 2011年第S1期18卷 724-729页

作者： Bhole s.D khan M.s Department of Mechanical and Industrial Engineering Ryerson University350 Victoria StreetTorontoONM5B 2K3Canada

The application of advanced high strength steels in automotive industry has highlighted the need for research into spot weldability of these *** weld lobe diagrams,the spot weldability of DP600 steel was found to be poor with conventional weld *** enhanced weld schedule consisting of two pulses with reduced current on the second pulse gave a substantial increase in the lobe width;the first pulse removed the zinc coating and the second pulse controlled the nugget growth.A data acquisition system was designed to monitor weld expulsion during the weld *** the three possible control strategies proposed,especially with AC welding equipment,the dynamic resistance signal is easily obtained and the least *** phenomena,microstructural characterization and mechanical properties of spot-welded hot dipped galvanized DP600 steel and interstitial free steel were *** work on dissimilar welds in DP 600 and HsLA 350 was also conducted with emphasis on tensile and fatigue properties and fracture *** performance of dissimilar spot welds was different from that of the similar spot welds in each of the HsLA350 and DP600 *** DP600 weld properties played a dominating role in the hardness and tensile properties of the dissimilar spot ***,the fatigue performance of the dissimilar welds was similar to that of the HsLA *** will be presented at the conference.

关键词： resistance spot welding dynamic resistance nugget diameter and hardness dissimilar materials microstructure mechanical properties fatigue fracture mode

A METHOD OF As-CAsT CRACk PREDICTION BAsED UPON NUMERICAL sIMULATION OF sOLIDIFICATION

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Acta Metallurgica sinica(English Letters) 2004年第6期17卷 817-822页

作者： X.s.Zheng s.Yao J.Z.Jin ResearchCenterofFoundryEngineering DalianUniversityofTechnologyDalian116024China

Based on the numerical simulation of solidification of castings, a thermal stress formula and a thermal crack initiation criterion are established, which suggest that the cracks initiate at the two-thirds thickness of solidified layer from outside of castings. Cast steel wheels whose diameters are 800mm are employed to testify the positions of cracks through thermal ela- stic-plastic analyses and low magnifying structure observations conventionally. The results show that the numerical prediction of cracks coincides with the measured result, and the cracks do not necessarily follow where the defects such as shrinkage holes and porosities occur. It is also found that surface temperature control is an effective factor to avoid the crack formation.

关键词： solidification crack initiation crack prediction numerical simulation

Exploration of Nonlinear Modeling Techniques to Predict the Retention Time of Organic Pollutants in Natural Water and Wastewater

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Chinese Journal of structural Chemistry 2012年第11期31卷 1580-1588页

作者： Zolfaghar Mehdizadeh Hamid Reza Lotfizadeh s.s.Mortazavi Hadi Noorizadeh Chief Executive Officer and Head of Ilam Regional Water Company Iran Faculty of science Ilam Branch Islamic Azad University Ilam Iran Young Researchers Club Hamedan Branch Islamic Azad University Hamedan Iran Department of Chemistry Faculty of Sciences Arak Branch Islamic Azad University Arak Iran

Water pollution affects plants and organisms living in these bodies of water; and, in almost all cases the effect is damaging not only to individual species and populations, but also to the natural biological communities. Genetic algorithm and kernel partial least square （GA-kPLs） and Levenberg- Marquardt artificial neural network （L-M ANN） techniques were used to investigate the correlation between retention time （tR） and descriptors for 150 organic contaminants in natural water and wastewater, which are obtained by gas chromatography coupled to high-resolution time-of-flight mass spectrometry （GC-TOF Ms）. The L-M ANN model gave a significantly better performance than the GA-kPLs model. This indicates that L-M ANN can be used as an alternative modeling toot for quantitative structure-retention relationship （QsRR） studies.

关键词： water samples organic pollutants gas chromatography time-of-flight massspectrometry QsRR Levenberg-Marquardt artificial neural network

Immune regulatory networks coordinated by glycans and glycan-binding proteins in autoimmunity and infection

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Cellular & Molecular Immunology 2023年第10期20卷 1101-1113页

作者： salomés.Pinho Inês Alves Joana Gaifem Gabriel A.Rabinovich i3s–Institute for Research and Innovation in Health University of Porto4200-135PortoPortugal ICBAs-school of Medicine and Biomedical sciences University of Porto4050-313PortoPortugal Faculty of Medicine University of Porto4200-319PortoPortugal Laboratorio de Glicomedicina Instituto de Biología y Medicina Experimental(IBYME)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)C1428Ciudad de Buenos AiresArgentina Facultad de Ciencias Exactas y Naturales Universidad de Buenos AiresC1428Ciudad de Buenos AiresArgentina

The immune system is coordinated by an intricate network of stimulatory and inhibitory circuits that regulate host responses against endogenous and exogenous *** of these safeguard and homeostatic mechanisms can lead to unpredictable inflammatory and autoimmune responses,whereas deficiency of immune stimulatory pathways may orchestrate immunosuppressive programs that contribute to perpetuate chronic infections,but also influence cancer development and *** have emerged as essential components of homeostatic circuits,acting as fine-tuners of immunological responses and potential molecular targets for manipulation of immune tolerance and activation in a wide range of pathologic *** surface glycans,present in cells,tissues and the extracellular matrix,have been proposed to serve as“self-associated molecular patterns”that store structurally relevant biological *** responsibility of deciphering this information relies on different families of glycan-binding proteins(including galectins,siglecs and C-type lectins)which,upon recognition of specific carbohydrate structures,can recalibrate the magnitude,nature and fate of immune *** process is tightly regulated by the diversity of glycan structures and the establishment of multivalent interactions on cell surface receptors and the extracellular *** we review the spatiotemporal regulation of selected glycan-modifying processes including mannosylation,complex N-glycan branching,core 2 O-glycan elongation,LacNAc extension,as well as terminal sialylation and ***,we illustrate examples that highlight the contribution of these processes to the control of immune responses and their integration with canonical tolerogenic ***,we discuss the power of glycans and glycan-binding proteins as a source of immunomodulatory signals that could be leveraged for the treatment of autoimmune inflammation and chronic infection.

关键词： Immune response Inflammation Infection Glycans Glycosylation Glycan-binding proteins

Diversity,Distribution and Prioritization of Fodder species for Conservation in kullu District,Northwestern Himalaya,India

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Journal of Mountain science 2007年第3期4卷 259-274页

作者： s. s. samant Man singh Manohar Lal shreekar Pant G.B.Pant Institute of Himalayan Environment & Development Himachal UnitMohal-Kullu175 126Himachal PradeshIndia

In the Indian Himalayan Region predominantly rural in character, livestock is one of the main sources of livelihood and integral part of the economy. Livestock mostly rely on fodder from wild. The diversity, distribution, utilization pattern, nativity, endemism, rarity, seasonality of availability, nutritive values, perceived economic values and pressure use index of livestock have not been studied. The present study attempts to enumerate 150 species of fodder representing trees (51 spp.), shrubs (54 spp.) and herbs (45 spp.). Poaceae (19 spp.) and Fabaceae (13 spp.) amongst families and salix (6 spp.), Ficus, Clematis, and Desmodium (5 spp., each) amongst genera are rich in species. Maximum species were found in the 1801 ~ 2600 m zone, and the remaining two zones showed relatively low diversity. Out of the 150 species, 109 are used in summer, 5 winter and 36 throughout year. During rainy season, mostly grasses are used as fodder. Only 83 species are native to the Himalayan region, one species, strobilanthus atropuroureus is endemic and 35 species are near endemic. The nutritive values of the fodder species were reviewed, and economic values and status of the species were also assessed. The pressure use index of the species was calculated on the basis of cumulative values of the utilization pattern, altitudinal distribution, availability, status, nativity and endemism. Amongst the species, Grewia oppositifoilia, Morus serrata, Indigofera heterantha, Quercus leucotrichphora, Ulmus villosa, U. wallichiana and Aesculus indica showed highest PUI indicating high preference and pressure. season wise prioritization of the species for different altitudinal zones has been done. Appropriate strategy and action plan have been suggested for the conservation and management of fodder species.

关键词： Diversity utilization native endemic nutritive and economic value pressure use index prioritization conservation Indian Himalayan Region