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Adaptability of the ocean and earth tidal models based on global observations of the superconducting gravimeters

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Science China Earth Sciences 2005年第11期48卷 1859-1869页

作者： Ducarme bernard Vandercoilden Leslie Royal Observatory of Belgium 3av. Circulaire B-1180 Brussels Belgium

The adaptability of recent ocean tidal models and Earth tidal models is investigated comprehensively by means of 22 high precision tidal gravity observation series at 20 stations of the Global Geodynamics Project. Careful preprocessing of the original observations was carried out using international standard algorithms and the tidal gravity parameters were computed. The gravity load vectors of 8 main constituents are obtained based on loading computation theory and various global ocean models. The loading corrections of 14 secondary constituents are obtained based on a two-dimensional interpolation technique. Considering different characteristics of the wave amplitude, a method of “non-identical weighted mean” is developed for computing the av-eraged observed residual and remaining residual vectors at each station. The efficiency of the loading correction and the discrepancy between corrected amplitude factors and theoretical ones are analyzed. Meanwhile the calibration problem of the instruments is also discussed. After loading correction, the averaged tidal gravity parameters for all stations are obtained. The results show that the discrepancies between the global mean amplitude factors and theoretical values are less than 0.3%, the largest calibration error of the instruments is less than 0.5%. On the other hand, there are indications that the slight phase advance of K1 with respect to O1 in Mathews’ theory could be verified by ground based tidal gravity observations.

关键词： superconducting gravimeters Global Geodynamics Project determination of the tidal gravity parameters verification of the global ocean and Earth tidal models.

Density Results in Sobolev Spaces Whose Elements Vanish on a Part of the Boundary

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Chinese Annals of Mathematics,Series B 2011年第6期32卷 823-846页

作者： Jean-Marie Emmanuel bernard Laboratoire Analyse et Probabitilités Université d'Evry val d'Essonne23 Boulevard de France91037 EVRYFrance

This paper is devoted to the study of the subspace of Wm＇＂ of functions that vanish on a part γ0 of the boundary. The author gives a crucial estimate of the Poincare constant in balls centered on the boundary of γ0. Then, the convolution-translation method, a variant of the standard mollifier technique, can be used to prove the density of smooth functions that vanish in a neighborhood of γ0, in this subspace. The result is first proved for m = 1, then generalized to the case where m 〉 1, in any dimension, in the framework of Lipschitz-continuous domain. However, as may be expected, it is needed to make additional assumptions on the boundary of γ0, namely that it is locally the graph of some Lipschitz-continuous function.

关键词： Density results Boundary value problems Sobolev spaces

Utilization of waste straw and husks from rice production:A review

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Journal of Bioresources and Bioproducts 2020年第3期5卷 143-162页

作者： bernard A.Goodman School of Physical Science and Technology Guangxi UniversityNanning 530004China School of Chemistry and Chemical Engineering Guangxi University for NationalitiesNanning 530008China

As a staple food for much of the world,rice production is ***,it also results in the generation of large quantities of non-food biomass,primarily in the form of straw and *** they have been little utilized and much rice straw is still simply burned,these ligno-cellulosic materials potentially have considerable *** review considers the composition of rice straw and husks,the various processes involved in the production of valuable products,and a range of uses to which they can be *** include agricultural amendments,energy production,environmental adsorbents,construction materials,and various speciality products.

关键词： Rice straw Rice husk Bioethanol Biogas Adsorbent Silica Cellulose Lignin

Soil Microbes and Sustainable Agriculture

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Pedosphere 2018年第2期28卷 167-169页

作者： bernard R. GLICK University of Waterloo Waterloo Ontario N2l 3G1 (Canada)

It has been estimated that a typical gram of soilcontains around 90 100 million bacteria and about200 000 fungi, with the majority of these organismsbeing located around the roots of plants. This locali-zation reflects the fact that plant roots typically exudea large fraction of the carbon that they fix by photo-synthesis, and soil microbes utilize this exuded carbonas a food source.

关键词： Soil Microbes Sustainable Agriculture plant roots food source

Strong Consistency and CLT for the Random Decrement Estimator

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Acta Mathematica Sinica,English Series 2010年第9期26卷 1613-1626页

作者： Pierre bernard Liang Zhen LEI Laboratoire de Mathematiques Universite Blaise Pascal CNRS 63177 Aubiere France Institute of Mathematical Sciences Capital Normal University Beijing 100048 P. R. China

The random decrement technique （RDT）, introduced in the sixties by Cole [NASA CR- 2005, 1973], is a very performing method of analysis for vibration signature of a structure under ambient loading. But the real nature of the random decrement signature has been misunderstood until now. Moreover, the various interpretations were made in continuous time setting, while real experimental data are obtained in discrete time. In this paper, the really implemental discrete time algorithms are studied. The asymptotic analysis as the number of triggering points go to infinity is achieved, and a Law of Large Numbers as well as a Central Limit Theorem is proved. Moreover, the limit as the discretization time step goes to zero is computed, giving more tractable formulas to approximate the random decrement. This is a new approach of the famous ＂Kac-Slepian paradox＂ [Ann. Math. Star., 30, 1215-1228 （1959）]. The main point might be that the RDT is a very efficient functional estimator of the correlation function of a stationary ergodic Gaussian process. Very fast, it is to classical estimators what Fast Fourier Transform （FFT） is to ordinary Discrete Fourier Transforms.

关键词： Random decrement estimator law of large numbers center limit theorem

Phosphorus requirements for containerized Pterocarpus indicus seedlings

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Journal of Forestry Research 2015年第3期26卷 657-662页

作者： Eng Hai Lok bernard Dell Forest Plantation Programme Forest Research Institute Malaysia 52109 Kepong Selangor Darul Ehsan Malaysia School of Veterinary and Life Sciences Murdoch UniversityPerth 6150 Australia

Pterocarpus indicus Willd is a tropical woody legume that holds promise for plantation forestry. Two glasshouse experiments were undertaken on two soil types to determine the phosphorus （P） concentration ranges in the foliage of P-stressed and healthy plants, and to define cri- tical P concentrations for the diagnosis of deficiency and toxicity. There was a narrow range in rates of P fertilizer, supplied as Ca（H2PO4）2.H2O, between deficiency and toxicity compared to other tree species. The relationship between shoot yield and P concentration in the youngest fully expanded leaf enabled critical P concentrations for the diagnosis of deficiency （0.17 %） and toxicity （0.41%） to be determined at 90 % maximum yield from linear re- gressions fitted to the data. The foliar P concentration ranges for deficiency and toxicity were similar to other nitrogen-fixing trees. The defined P concentration ranges and the critical P concentrations for the diagnosis of P deficiency and P toxicity should be useful for monitoring the P status of nursery stock and the health of young seedlings after out-planting.

关键词： Deficiency Diagnosis Nutrition Symptoms Toxicity

Effect of Bimodal Grain Size Distribution on the Strain Hardening Behavior of a Medium-Entropy Alloy

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Acta Metallurgica Sinica(English Letters) 2021年第4期34卷 465-475页

作者： Ibrahim Ondicho bernard Alunda Fredrick Madaraka Melody Chepkoech Department of Mechanical Engineering Dedan Kimathi University of TechnologyPrivate bag-10143Dedan KimathiNyeriKenya Materials Designand Manufacturing(MADEMA)GroupDedan Kimathi University of TechnologyPrivate Bag-10143Dedan KimathiNyeriKenya Department of Mining and Minerals Processing Engineering Taita Taveta UniversityP.O.Box 635-80300VoiKenya Department of Mechanical Engineering Howard University23006th Street NWWashingtonDCUSA

The evolution of strain hardening behavior of the Fe_(50)(CoCrMnNi)_(50) medium-entropy alloy as a function of the fraction of recrystallized microstructure and the grain size was studied using the Hollomon and Ludwigson *** specimens under study were partially recrystallized,fully recrystallized with ultrafine-grained microstructure,and fully recrystallized with coarse *** yield strength decreases steadily as the fraction of recry stallized micro structure and grain size increases due to the recovery process and the Hall-Petch ***,the bimodal grain distribution was found to have a significant impact on strain hardening during plastic *** instance,the highest ultimate tensile strength was exhibited by a 0.97 μm specimen,which was observed to contain a bimodal grain ***,using the Ludwigson equation,the effect of the bimodal grain distribution was established from the behavior of K_(2) and n_(1) *** curves tend to show very high values in the specimens with a bimodal grain distribution compared to those that show a homogenous grain ***,the bimodal grain distribution contributes to the extensive Luders strain observed in the 0.97 μm specimen,which induces a significant deviation of the Hollomon equation at lower strains.

关键词： Metals and alloy Mechanical properties Microstructure High-entropy alloys Plastic deformation

DEVS and MBSE:A review

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International Journal of Modeling, Simulation, and Scientific Computing 2022年第2期13卷 31-46页

作者： bernard P.Zeigler Department of Electrical&Computer Engineering College of Engineering The University of Arizona TucsonAZ 85721USA RTSync Corp. ChandlerAZ 85226USA

We review Discrete-Event system Specification(DEVS)in the context of Model-based Systems Engineering(MBSE)and discuss an application of DEVS methodology to *** outline support for an envisioned MBSE development cycle of DEVS top-to-bottom MBSE capability and offer an example of mapping UML activity diagrams into executable activity-based DEVS *** close with conclusions and future research directions.

关键词： Discrete-event system specification DEVS model-based systems engineering MBSE UML activity diagrams homomorphisms system design activity-based models

Zygotic chromosomal structural aberrations after paternal drug treatment

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Asian Journal of Andrology 2015年第6期17卷 939-941页

作者： Anne Marie Downey bernard Robaire Departments of Pharmacology and Therapeuticsand of Obstetrics and Gynecology McGill UniversityMontreal Quebec Canada.

In recent years, the field of male-mediated reproductive toxicology has received growing attention. It is now well-established that many drugs, chemicals, and environmental factors can harm male germ cells by inducing DNA damage. Male germ cells have extensive repair mechanisms that allow detection and repair of damaged DNA during the early phases of spermatogenesis. However, during the later phase of spermiogenesis, when the haploid spermatids undergo chromatin condensation and become transcriptionally quiescent, their ability to repair damaged DNA is lost. It is also thought that the highly compacted chromatin of the sperm can protect DNA against damage. Therefore, it is expected that late spermatids will be most susceptible to DNA damaging agents. Unrepaired or misrepaired damage in the germ cells leads to the generation of spermatozoa with DNA damage that can be transmitted to the next generation. Fortunately, the maternal DNA repair machinery is capable of recognizing and repairing, at least to some degree, damaged paternal DNA after fertilization in the zygote. Therefore, the efficiency of the maternal repair machinery will greatly influence the risk of transmitting paternal DNA damage to offspring.

关键词： Zygotic chromosomal treatment