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Geochemistry of Kestelek Colemanite Deposit, Bursa, Turkey

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Journal of Earth science 2017年第1期28卷 63-77页

作者： sükrü Koc Ozge Kavrazh ismail Kocak Faculty of Department of Geological Engineering Ankara University Ankara 06100 Turkey Graduate school of Natural and Applied sciences Ankara University Ankara 06100 Turkey Department of Geological Engineering Bozok University Yozgat 66100 Turkey

The Kestelek borate deposit has been the subject of geological and mineralogical research over the last decades, but major and trace element geochemistry of this deposit was first investigated in the present study. A total of 22 samples collected from surface exposures and different depths of deposit in boreholes（e.g., lower, middle and upper） comprise the material of this.study. Major, trace and REE element analys.s of samples were conducted with ICP-Ms and ICP-Es methods. The Kestelek borate deposit of Miocene age was formed in playa lakes in an intermountain closed basin which was developed in volcanically and seismically active areas associated with growth faults and grabens affected the whole Anatolia at the beginning of Paleogene. Only colemanite was found as the borate mineral accompanied in lesser amount by calcite, aragonite, smectite, illite, chlorite, corrensite, heulandite and quartz. In colemanite samples, all major elements, except for Ca, show depletion trends with respect to average of earth crust and andesite. For the trace elements, Li, Cs, sb, As, sr and se are characterized by significantly high concentrations. Evaluation of element concentrations and geochemical characteristics reveal that As, Cs, sb and Li are of detrital origin, se together with B and Ca are of non-detrital and sr is indicative of both detrital and non-detrital origin. REE distributions indicate that at least two different depositional regimes prevail in the environment. Corrensite, a clay mineral forming in lake waters, is derived from volcanism. Negative Ce and positive Eu anomalies are indicative of contribution from hydrothermal solutions and fluids.

关键词： borate mineralogy geochemistry REE Kestelek Turkey.

Genetic divergence for growth and wood parameters in different clones of Dalbergia s.ssoo Roxb

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Journal of Forestry Research 2012年第2期23卷 285-288页

作者： Kumar A Bhatt A Ravichandran s Pande PK Dobhal s Forest Research Institute (Indian Council of Forestry Research and Education) Dehradun 248 195 Uttarakhand India Directorate of Rice Research Rajendra Nagar Hyderabad-500030 Andhra Pradesh India

The wood analys.s for different parameters was carried out in a clonal seed orchard ofDalbergia s.ssoo Roxb. established during 1997 at Hoshiarpur, Punjab, India. Twelve clones with higher index value were subjected to Euclidean Cluster Analys.s based on wood and growth parameters to group into seven clusters. Cluster I and II contained four and three clones, respectively, and remaining clusters bad just one clone each. Clone originated from Barielly, Uttar Pradesh of cluster VII was found to be the most divergent clone. Cluster II with three clones main- tained greater inter cluster distance with other clusters. The divergence analys.s has confirmed that the clones planted in the clonal seed orchard are sufficiently divergent and seed harvested from the orchard would maintain high diversity.

关键词： Dalbergia s.ssoo Roxb. seed orchard wood and growthtraits genetic divergence hybridization

An optimized ion trap geometry to measure quadrupole shifts of ^(171)Yb~＋ clocks

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Chinese Physics B 2016年第11期25卷 230-237页

作者： N Batra B K sahoo s De Academy of scientific and Innovative Research CSIR-NPL Campus New Delhi India CsIR-National Physical Laboratory Dr. K. S. Krishnan Marg New Delhi 110012 India Theoretical Physics Division Physical Research Laboratory Navrangpura Ahmedabad 380009 India

We propose a new ion-trap geometry to carry out accurate measurements of the quadrupole shifts in the （171）Yb *** trap will minimize the quadrupole shift due to the harmonic component of the confining potential by an order of *** will be useful to reduce the uncertainties in the clock frequency measurements of the 6s 2s（1/2）→4f（13）6s2 2F（7/2）and 6s 2s（1/2）→5d2D（3/2） transitions,from which we can deduce the precise values of the quadrupole moments（0s） of the 4f（13）6s2 2F（7/2） and 5d2D（3/2） ***,it may be able to affirm the validity of the measured 0 value of the4f（13）6s22F（7/2） state,for which three independent theoretical studies defer almost by one order of magnitude from the *** also calculate 0s using the relativistic coupled-cluster（RCC） *** use these 0 values to estimate the quadrupole shift that can be measured in our proposed ion trap experiment.

关键词： validity minimize carry clock relativistic precise deduce magnitude expectation spatially

Near-surface Correction on seismic and Gravity Data

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Journal of Earth science 2015年第6期26卷 851-857页

作者： s.Bychkov I.Y.Mityunina Perm state University Mining Institute of Ural Branch of Russian Academy of Sciences

It is important and urgent to work out better statics correction methods to facilitate seismic prospecting. This paper presents a new method of statics correction calculation based on development of a seismic-gravity model of the near surface. Gravity interpretation includes determination of the local component caused by the near surface effects and calculation of the near-surface rock density by solving the linear inverse gravity problem. To obtain the near-surface velocities, priori seismic data such as time fields of the first waves recorded in the initial part of common depth point（CDP） seismograms are used. An optimal near-surface model is retrieved on the bas.s of the successive solution of the inverse and forward seismic problems, correlating with the observed seismic data. Matching of seismic and gravity model of the near surface yields the maximum coefficient of correlation between the values of velocities and densities. At the end of the interactive iterative process we get values of the near-surface seismic wave velocities, used for statics evaluation, and values of gravity anomalies, calculated with a variable density of the interbedded layer. The applications of the proposed method at geophysical exploration of oil and gas confirm the possibility of calculation of statics correction using the gravimetric data by constructing a coherent seismic-gravity model of the near surface.

关键词： gravity near-surface velocity seismic-gravity model statics correction.

On the Application of PCA Technique to Fault Diagnos.s

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Tsinghua science and Technology 2010年第2期15卷 138-144页

作者： DING s ZHANG P DING E YIN s Naik A DENG P GUI W Institute for Automatic Control and Complex s.stems (AKs) University of Duisburg-Essen 47057 Duisburg Germany Department of Physical Engineering University of Applied Sciences Gelsenkirchen 45877 Gelsenkirchen Germany school of Information science and Engineering Central South University Changsha 410083 China

In this paper, we bdefly address the application of the standard principal component analys.s （PCA） technique to fault detection and identification. Based on an analys.s of the existing test statistic, we propose a new test statistic, which is.similar to the Hawkin＇s T2 H statistic but without the numerical drawback. In comparison with the sPE index, the threshold setting associated with the new statistic is computationally simpler. Our further study is dedicated to the analys.s of fault sensitivity. We consider the off-set and scaling faults, and evaluate the test statistic by viewing its.sensitivity to the faults. Our final study focus.s on identifying off-set and scaling faults. To this end, two algorithms are proposed. This paper also includes.some critical remarks on the application of the PCA technique to fault diagnos.s.

关键词： process monitoring fault diagnos.s principal component analys.s (PCA) multivariate analys.s

C_c(X)spaces with X Locally Compact

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Acta Mathematica sinica,English series 2007年第9期23卷 1593-1600页

作者： J.C.FERRANDO s.MOLL Centro de Investigación Operativa Universidad Miquel Hernández Departamento de Matemática Aplicada Universidad Politécnica

In this paper, we show, among other results, that if X is a [separable] locally compact space X [satisfying the first countability axiom] then the space Cc （X） has countable tightness [if and only if it has bounding tightness] if and only if it is Frechet-Urysohn, if and only if Cc （X） contains a dense （LM） subspace and if and only if X is a-compact.

关键词： Frechet-Urysohn space countable [bounding] tightness (LM)-space

FINITE DIFFERENCE METHODs FOR THE HEAT EQUATION WITH A NONLOCAL BOUNDARY CONDITION

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Journal of Computational Mathematics 2015年第1期33卷 17-32页

作者： V. Thomee A.s. Vasudeva Murthy Mathematical sciences Chalmers University of Technology and University of Gothenburg SE-412 96 GSteborg Sweden TIFR Centre for Appl. Math Yelahanka New Town Bangalore India

We consider the numerical solution by finite difference methods of the heat equation in one space dimension, with a nonlocal integral boundary condition, resulting from the truncation to a finite interval of the problem on a semi-infinite interval. We first analyze the forward Euler method, and then the 0-method for 0 〈 θ ≤ 1, in both cas.s in maximum-norm, showing O（h2 ＋ k） error bounds, where h is the mesh-width and k the time step. We then give an alternative analys.s for the case θ= 1/2, the Crank-Nicolson method, using energy arguments, yielding a O（h2 ＋ k3/2） error bound. special attention is given the approximation of the boundary integral operator. Our results are illustrated by numerical examples.

关键词： Heat equation Artificial boundary conditions unbounded domains productquadrature.

separation of closely spaced modes by combining complex envelope displacement analys.s with method of generating intrinsic mode functions through filtering algorithm based on wavelet packet decomposition

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Applied Mathematics and Mechanics(English Edition) 2013年第7期34卷 801-810页

作者： Y.s.KIM 陈立群 shanghai Institute of Applied Mathematics and Mechanics Department of Mechanics Kim Ⅱ Sung University Department of Mechanics College of Sciences Shanghai University shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai University

One of the important issues in the s.stem identification and the spectrum analys.s is the frequency resolution, i.e., the capability of distinguishing between two or more closely spaced frequency components. In the modal identification by the empirical mode decomposition （EMD） method, because of the separating capability of the method, it is.still a challenge to cons.stently and reliably identify the parameters of structures of which modes are not well separated. A new method is introduced to generate the intrin- sic mode functions （IMFs） through the filtering algorithm based on the wavelet packet decomposition （GIFWPD）. In this paper, it is demonstrated that the CIFWPD method alone has a good capability of separating close modes, even under the severe condition beyond the critical frequency ratio limit which makes it impossible to separate two closely spaced harmonics by the EMD method. However, the GIFWPD-only based method is impelled to use a very fine sampling frequency with consequent prohibitive computational cos.s. Therefore, in order to decrease the computational load by reducing the amount of samples and improve the effectiveness of separation by increasing the frequency ratio, the present paper us.s a combination of the complex envelope displacement analys.s （CEDA） and the GIFWPD method. For the validation, two examples from the previous works are taken to show the results obtained by the GIFWPD-only based method and by combining the CEDA with the GIFWPD method.

关键词： empirical mode decomposition (EMD) wavelet packet decomposition com- plex envelope displacement analys.s (CEDA) closely spaced modes modal identification

The andropause and memory loss: is there a link between androgen decline and dementia in the aging male?

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Asian Journal of Andrology 2001年第3期3卷 169-174页

作者： Robert s.Tan shou-Jin Pu Geriatric Medicine Fellowship Program University of Texas Houston United StatesGeriatric Medicine Fellowship Program University of Texas Houston United States

studies demonstrate a decline in androgens with age and this results in the andropause. The objective of this paperis to review the literature on hormonal changes that occur in the aging males and determine if there are associations be-tween decreased testosterone, dehydroepiandrosterone (DHEA) and decreased cognitive function. Trials of androgen re-placement and its impact on cognitive function will also be analyzed. Method of analys.s will be by a thorough searchof articles on MEDLINE, the Internet and major abstract databas.s. Results of the author's own research in 302 men ofthe association of memory loss as a symptom in the andropause will be presented. In addition, the authors open trial oftestosterone replacement in hypogonadic men with Alzheimer's disease will also be presented. The results of the author'strial will be compared with other investigators. High endogenous testosterone level predicted better performance on visu-al spatial tes.s in several studies, but not in all studies. Likewise, testosterone replacement in hypogonadic patients im-proved cognitive functions in some but not all studies. Testosterone has also been shown to improve cognitive functionin eugonadal men. several studies have shown that declines in DHEA may contribute to Alzheimer's disease and the re-sults of double blind studies with DHEA replacement and its effect on cognition will also be presented. In summary,there is.still no consens.s that androgen replacement is beneficial in cognitive decline but this option may prove promis-ing in some patients. (Asian J Androl 2001 sep; 3: 169-174)

关键词： andropause memory loss androgens testosterone aging dementia