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Characteristics of climate change in the “significant impact zone” affected by aerosols over eastern China in warm seasons

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Science China Earth Sciences 2008年第5期51卷 730-739页

作者： SHI XiaoHui1, XU XiangDe1, XIE LiAn2.1 state Key Laboratory of Severe Weather, Chinese Academy of Meteorological Sciences, Beijing 100081, China 2.department of marine, Earth and Atmospheric Sciences,{2., raleigh nc2.695-82.8, usa state Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences department of marine Earth and Atmospheric Sciences North Carolina State University

Through analysis of the distribution pattern and changing characteristics of atmospheric aerosols over the East Asia region during warm seasons in recent 2. a and beyond as well as their possible interac- tive relationship with a variety of meteorological elements, it is found that the high-value zone of aerosol optical depth derived from the Total Ozone Mapping Spectrometer (TOMS), its significant negative correlation zones in terms of sunshine duration (SD) and surface air temperature (SAT) and its significant positive correlation zones with low-level cloud amount (LCC) are co-located in the South China region during warm periods. Based on this finding, the region is referred to as a "significant impact zone" (SI zone) affected by aerosols. Then, a comparative analysis is made on variation differ- ences of observed SAT, SD and LCC, etc. in different regions. It is also found that the LCC is increased and the SD is decreased within the "SI zone" over eastern China during the warm season. These characteristics are more evident than those beyond the zone, while the warming trend within the zone is evidently weaker than that outside it. Studies show that since recent 2. a, under the influence of aerosols, the LCC tend to increase substantially with a clear decrease of SD and an unnoticeable warming trend within the "SI zone". Comparing with the climate change beyond the zone, the difference is significant. Therefore, the effects of atmospheric aerosols on climate is possibly one of the contri- butions to the difference of climate change existed between the southern and northern parts of the Eastern China during a warm season.

关键词： warm season significant impact zone of aerosols climate change

Heat treatment of novel low-carbon multi-alloyed anti-wear marine steel

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Progress in Natural Science:Materials International 2011年第3期21卷 254-261页

作者： Jing-hua JIANG~(1,2.,Qiu-yue WANG~1,Ai-bin MA~(1,2.,Jun SHI~1,Liu-yan ZHANG~1, Hui-dong YANG~(2.3),Fu-min LU~2.Qi ZHOU~2.1.National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety, Hohai university,Nanjing 2.0098,China 2.College of Mechanics and Materials,Hohai university,Nanjing 2.0098,China 3.{2. of Mechanical and Aerospace Engineering,north carolina state university, raleigh,north carolina 2.695-7919,usa National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai University Nanjing 210098 China College of Mechanics and Materials Hohai University Nanjing 210098 China department of Mechanical and Aerospace Engineering North Carolina State University Raleigh North Carolina 27695-7919 USA

A low-carbon anti-wear steel,multi-alloyed with Si-Cr-Mn-Al-Ni-Mo-（Nb,RE）,was designed for vane pumps of ships. The novel cast steel after various heat treatments was characterized by microstructure observations and mechanical properties measurement in order to achieve an optimal process correlated with good abrasive resistance for a long marine *** scanning calorimetry and hardness analyses deduced a complete austenitizing temperature of 1 000℃,based on the alloying element homogenization and defective structure elimination without grain *** optimal austempering process（austenitized at 1 000℃,quick cooled for holding at 350℃for 1.5 h and then air-cooled to room temperature） produced a uniform mixture structure of fine carbide-free aciculate bainites and few lath martensites,resulting in the tensile strength increase of 34%and impact toughness increase of 50%compared with that of the as-cast *** abrasive wheel tests show that the austempered steel has good wear resistance with a mass-loss rate of 170 mg/（km·cm2. under applied load of 70 N in acidic *** new grade steel （containing anti-corrosion elements of Cr and rare earth） can find wide application in marine engineering,with further enhanced comprehensive properties via melting process improvement.

关键词： abrasive resistance carbide-free bainite marine steel mechanical performance heat treatment

MINIMIZING A LINEAR FRACTIONAL FUncTION SUBJECT TO A SYSTEM OF SUP-T EQUATIONS WITH A CONTINUOUS ARCHIMEDEAN TRIANGULAR NORM

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Journal of Systems Science & Complexity 2009年第1期22卷 49-62页

作者： Pingke LI Edward P.Fitts department of Industrial and Systems Engineering,north {2. state university,raleigh,nc 2.695-7906,US Shu-Cherng FANG Edward P.Fitts department of Industrial and Systems Engineering,north {2. state university,raleigh,nc 2.695-7906,usa department of Mathematical Sciences,Tsinghua university,Beijing 100084,China College of Management,Dalian university of Technology,Dalian 11602.,China. department of Industrial and Systems Engineering North Carolina State University

This paper shows that the problem of minimizing a linear fractional function subject to asystem of sup-T equations with a continuous Archimedean triangular norm T can be reduced to a 0-1linear fractional optimization problem in polynomial ***,parametrization techniques,e.g.,Dinkelbach's algorithm,can be applied by solving a classical set covering problem in each *** reduction can also be performed on the sup-T equation constrained optimization problems withan objective function being monotone in each variable *** method could be extended aswell to the case in which the triangular norm is non-Archimedean.

关键词： Fractional optimization fuzzy relational equations triangular norms.

QUEUEING NETWORKS WITH INSTANTANEOUS SEQUENTIAL TRANSITIONS

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Journal of Systems Science & Complexity 2001年第3期14卷 225-238页

作者： Xiuli Chao (department of Industrial Engineering and Interdisciplinary OR Programs, north carolina state university, {2., nc 2.695-7906, usa) north carolina {2.d Univers 美国 NC27695-79

We study queueing networks with instantaneous transitions of sequential batch departures and sequential batch arrivals. Unlike most of the existing models, this network is shown not to have a product form solution. An "extra arrival condition" is introduced under which the network is shown to possess a product form stationary distribution. Fur- thermore, the product form solution serves as a stochastic upper bound for the original network without the extra arrival process. The results include many queueing network models reported in the literature, e.g. the assembly transfer networks recently introduced by Miyazawa and Taylor, as special cases. We show that the network with the extra arrival process is "structurally reversible" in the sense that its reversed process has the same network structure. Local balances for this network are presented and discussed.

关键词： Networks of queues string transitions partial balance product form solution non-linear traffic equations.

On the direct path problem of s-elementary frame wavelets

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Science China Mathematics 2010年第12期53卷 3187-3196页

作者： DAI XingDe 1 , DIAO YuanAn 1 & GUO XunXiang 2.1 department of Mathematics and Statistics, university of {2. carolina at Charlotte, Charlotte, nc 2.2.3, usa 2.department of Mathematics, Southwestern university of Finance and Economics, Chengdu 611130, China department of Mathematics and Statistics University of North Carolina at Charlotte department of Mathematics Southwestern University of Finance and Economics

In this paper, we discuss the path-connectivity between two s-elementary normalized tight frame wavelets via the so-called direct paths. We show that the existence of such a direct path is equivalent to the non-existence of an atom of a σ-algebra defined over the defining sets of the corresponding frame wavelets, using a mapping defined by the natural translation and dilation operations between the sets. In particular, this gives an equivalent condition for the existence of a direct path between two s-elementary wavelets.

关键词： wavelets frame wavelets frame wavelet sets path-connectivity of wavelets direct path

METHODS FOR DETECTION AND ESTIMATION OF LINKAGE BETWEEN A MARKER LOCUS AND QUANTITATIVE TRAIT LOCI Ⅰ. USING F2.FAMILY SUBPOPULATION

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生物数学学报 1992年第1期 12-21页

作者： Hu Zhongli~*(department of Biology, wuhan university, wuhan 430072. China) Chardes W. Stuber~**(Departmem of Genetics,{2., raleigh nc 2.095-7614, usa)

Several methods heve been proposed over the years to detect linkage between a marker gene and a quantitative trait locus (QTL). Use of isozymes and restriction fragment length polymorphisms (RFLPs) as genetic markers has encouraged the development of new methods to detect linkage. In the paper authors present three methods to detect linkage and two methods to measure recombination frequency (r). The three methods that detect linkage are fit for the test of one or several QTLs of quantitative trait considered as long as the net gene effect vaIue of all loci belonging to a linkage cluster is greater significantly than zero, irrespective of their linkage relationship among the several QTLs.

关键词： Detection of linkage Recombination frequency QTLs Isozymes RFLPs.

CLUSTERING POPULATIONS BY MIXED LINEAR MODELS

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生物数学学报 1994年第3期9卷 1-14页

作者： JUN ZHU BRUCE S. WEIR(department of Agronomy,Zhejiang Agricultural university, Hangzhou 31002., Zhejiang, CHINA)(department of Statistics, north carolina state university, raleigh,nc 2.695-82.3, usa)

Two mixed linear models are proposed for grouping populations by a dissimilarity coefficent which has two parameters for squared difference of marginal mean and variance component of *** trees can be constructed by the mixed linear model approaches for experimental data with sampling errors within populations or with some missing *** pair-group method ( UPGM ) is suggested as fusion method. Sampling variances of estimated dissimilarity coefficient can be obtained by the jackknife procedure.A one-tail t-test is applicable for detecting significance of dissimilarity of populaions within specific *** and efficiency for estimation of dissimilarity coefficients are proved by Monte Carolo *** example from cotton yield data is given for demonstration of the use of these cluster methods.

关键词： Cluster method Mixed linear models Monte carlo simulation Genotypexenvironment interaction.

A three dimensional implicit immersed boundary method with application

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Theoretical & Applied Mechanics Letters 2011年第6期1卷 22-25页

作者： Jian Hao1,2.and Luoding Zhu1, 1)department of Mathematical Sciences and Center for Mathematical Biosciences Indiana university - Purdue university, Indianapolis, IN 462.2. usa 2.department of Mathematics and Center for Research in Scientific Computation, north carolina state university, raleigh, nc 2.695, usa department of Mathematical Sciences and Center for Mathematical Biosciences Indiana university - Purdue university Indianapolis 46202 IN United States department of Mathematics and Center for Research in Scientific Computation North Carolina State University Raleigh 27695 NC United States

Most algorithms of the immersed boundary method originated by Peskin are explicit when it comes to the computation of the elastic forces exerted by the immersed boundary to the fluid. A drawback of such an explicit approach is a severe restriction on the time step size for maintaining numerical stability. An implicit immersed boundary method in two dimensions using the lattice Boltzmann approach has been proposed. This paper reports an extension of the method to three dimensions and its application to simulation of a massive flexible sheet interacting with an incompressible viscous flow.

关键词： immersed boundary method lattice-Boltzmann method implicit schemes fluid-structure-interaction bi-stability flag-in-wind

Effciency comparison between mean and log-rank tests for recurrent event time data

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Science China Mathematics 2009年第6期52卷 1169-1180页

作者： LU WenBin department of Statistics, north carolina state university, {2., nc 2.695, usa

Recurrent event time data are common in biomedical follow-up studies, in which a study subject may experience repeated occurrences of an event of interest. In this paper, we evaluate two popular nonparametric tests for recurrent event time data in terms of their relative effciency. One is the log-rank test for classical survival data and the other a more recently developed nonparametric test based on comparing mean recurrent rates. We show analytically that, somewhat surprisingly, the log-rank test that only makes use of time to the first occurrence could be more effcient than the test for mean occurrence rates that makes use of all available recurrence times, provided that subject-to-subject variation of recurrence times is large. Explicit formula are derived for asymptotic relative effciencies under the frailty model. The findings are demonstrated via extensive simulations.

关键词： asymptotic relative effciency frailty model log-rank test proportional mean test recurrent events robust variance estimation