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Bone gain and loss: insights from genomes and fossils

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National Science Review 2014年第4期1卷 490-492页

作者： Min Zhu Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences

In the human body,bones are dynamic and highly tuned organs that allow eicient movement,protect vital organs and house the bone marrow[1].Among the four skeletal tissue types(bone,dentine,enamel,cartilage)in vertebrates,bone is the most distinct and diversiied mineralized tissue that is paterned to provide maximal strength with minimal mass[2].Based on the bone formation or ossiication types in the embryos and young

关键词： Gln pro In insights from genomes and fossils Bone gain and loss bone

Effect of Nonlinear Dynamic process on Formation and Breakdown of Blocking

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Advances in Atmospheric Sciences 1991年第1期8卷 41-50页

作者：张佩倪允琪 Meteorological Institute of Jiangsu Nanjing 210008 Department of Atmospheric Sciences Nanjing University Nanjing 210008ith the L-P approximate method(variation of parameter method) a barotropic channel model in β-plane is used to study the effect of nonlinear interaction between two waves with different scales on the formation of blocking. The approximate analytical solution which can describe the process of the blocking formation maintenance and breakdown has been obtained by using the method of aproximate expansion. The importance of nonlinear interaction between two waves with different scales is stressed in the solution. The result suggests that the nonlinear interaction is the main dynamic process of the blocking formation. Some required conditions of blocking formation are also discussed.

With the L-P approximate method(variation of parameter method), a barotropic channel model in β-plane is used to study the effect of nonlinear interaction between two waves with different scales on the formation of blocking. The approximate analytical solution, which can describe the process of the blocking formation, maintenance and breakdown, has been obtained by using the method of aproximate expansion. The importance of nonlinear interaction between two waves with different scales is stressed in the solution. The result suggests that the nonlinear interaction is the main dynamic process of the blocking formation. Some required conditions of blocking formation are also discussed.

关键词： pro Effect of Nonlinear Dynamic process on Formation and Breakdown of Blocking

A Methodology for Development of Software Composite-Metrics for program Control-Flow Structure

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Journal of Computer Science & Technology 1992年第3期7卷 202-218页

作者： Aftab Ahmad Dept. of Computer Science College of Computer and Information Sciences King Saud University Riyadh 11543 Saudi Arabia

This paper reports on a pioneer effort for the establishment of a software composite metric with key capability of distinguishing among different structures. As a part of this effort most of the previously proposed program control-flow complexity metrics are evaluated. It is observed that most of these metrics are inherently limited in distinguishing capability. However, the concept of composite metrics is potentially useful for the development of a practical metrics. This paper presents a methodology for the develop- ment of a practical composite metric using statistical techniques. The proposed metric differs from all previous metrics in 2 ways: (1) It is based on an overall structural analysis of a given program in deeper and broader context. It captures various structural measurements taken from all existing structural levels; (2) It unifies a set of 19 important structural metrics. The compositing model of these metrics is based on statistical techniques rather than on an arbitrary method. Experinces with the pro- posed metric clearly indicate that it distinguishes different structures better than the previous metrics.

关键词： pro A Methodology for Development of Software Composite-Metrics for program Control-Flow Structure

Literate programming System CDS

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Journal of Computer Science & Technology 1991年第3期6卷 263-270页

作者：曾云峰 Institute of software Academia Sinica Beijing 100080

This paper presents a broad outline and some implementation techniques of the literate programming system CDS.Compared with the previous ones(e.g.WEB,Cweb),CDS has two main characteristics: 1)A Chinese-English typesetting system was developed to produce the documentation.This makes the Chinese documentation possible.2)A suitable method for automatic formatting was introduced to gener- ate the software documentation automatically.This frees the programmer from typesetting details while still allowing programmer's interference.

关键词： Literate programming System CDS pro

Hausdorff Dimension of the Sample Path of the Westwater process

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Acta Mathematica Sinica,English Series 1992年第1期8卷 26-45页

作者：周先银 Department of Mathematics Beijing Normal University Beijing 100875China

In this paper,we prove that the Hausdorff dimension of the sample path of thethree dimensional coordinate process is exactly two a.e.-v(g),where v(g)is the polymer measureconstructed by Westwater.Furthermore,we prove that the sample path of the Westwater processhas also zero Hausdorff 2-measure.This answers a problem suggested by E.Nelson.

关键词： pro Hausdorff Dimension of the Sample Path of the Westwater process Path 一刀

The Dirichlet problem of a Discontinuous Markov process

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Acta Mathematica Sinica,English Series 1989年第1期5卷 9-15页

作者：廖明 Department of Mathematics Nankai University

Given a Markov process satisfying certain general type conditions,whose paths are notassumed to be continuous. Let D by an open subset of the state space E. Any bounded function defined on thecomplement of D extends to be a function on E (?)uch that it is harmonic in D and satisfies the Dirichletboundary condition at any regular boundary point of D. The relation between harmonic functions and theebaracteristic operator of the given process is discussed.

关键词： The Dirichlet problem of a Discontinuous Markov process pro

On the Tensor products of Operators

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Acta Mathematica Sinica,English Series 1993年第2期9卷 195-202页

作者：侯晋川 Department of Math. Shanxi Teachers Univ. Linfen China

In this paper some necessary and sufficient conditions are obtained for a operatortensor product ∑AA…Ato be zero, compact, normal, hyponormal, subnormal,essential normal, k-quasihyponormal, etc.

关键词： pro On the Tensor products of Operators

Simulation of the Influence of Ion-produced NO_X and HO_X Radicals on the Antarctic Ozone Depletion with a One-Dimensional Model

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Advances in Atmospheric Sciences 1990年第1期7卷 98-103页

作者：王贵勤 Department of Geophysics Peking University Beijing 100871 one -dimensional time-dependent photochemical model is used to simulate the influence of ion-produced NOx and HOx radicals on the Antarctic ozone depletion in polar night and polar spring at a latitude of 73 degrees south.Vertical transport and nitrogen-oxygen (NOx). hydrogen-oxygen (HOx) production by ionic reactions have been introduced into the model.NOx and HOx produced by precipitating ions are transported into the lower stratosphere by vertical motion and have some effects in the development of the Antarctic ozone depletion.From winter through spring the calculated ozone column decreases to 269.4 DU. However this value is significantly higher than the total ozone observed at several Antarctic ozone stations.

A one -dimensional time-dependent photochemical model is used to simulate the influence of ion-produced NOx and HOx radicals on the Antarctic ozone depletion in polar night and polar spring at a latitude of 73 degrees south.Vertical transport and nitrogen-oxygen (NOx). hydrogen-oxygen (HOx) production by ionic reactions have been introduced into the model.NOx and HOx produced by precipitating ions are transported into the lower stratosphere by vertical motion and have some effects in the development of the Antarctic ozone depletion.From winter through spring the calculated ozone column decreases to 269.4 DU. However, this value is significantly higher than the total ozone observed at several Antarctic ozone stations.

关键词： pro In Simulation of the Influence of Ion-produced NO_X and HO_X Radicals on the Antarctic Ozone Depletion with a One-Dimensional Model NO

The UNIX Localization and Chinese Information processing System

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Journal of Computer Science & Technology 1991年第4期6卷 370-375页

作者：孙玉方 Institute of Software Academia SinicaBeijing 100080

To facilitate the wider use of computers all over the world,it is necessary to provide National Language Support in the computer systems.This paper introduces some aspects of design and implementation of the UNIX-based Chinese Information processing Systems(CIPS). Due to the special nature of the Oriental languages,and in order to be able to share resources and ex- change information between different countries,it is necessary to create a standard of multilingual informa- tion exchange code.The Unified Chinese/Japanese/Korean character code,Han Character Collec- lion(HCC),was proposed to ISO/IEC JTC1/SC2/ WG2 by China Computer and Information pro- cessing Standardization Technical Committee.Based on this character set and the corresponding coding sys- tem,it is possible to create a true Internationalized UNIX System.

关键词： UNIX pro 研究与发展 AT 研究与开发 The UNIX Localization and Chinese Information processing System code