铜川矿区5#

铜川矿区     

Application of uniform DFT filter bank in radar jamming system

1 .INTRODUCTIONWith the rapid development of radar technology ,The technology of high-resolution radar i mage for-mationis gradually getting mature , and the coun-termeasure to high-resolution radar is growing a re-search hot point in the field of ECM. In order toattain high-resolution, High-resolutionradar usual-ly adopts the wideband pulse signal with 1 GHzbandwidth and over . So the realization of A/D( Analog/Digital) conversionis more difficult in en-gineering practice . For the s…     

公众参与环境保护共建环境友好型社会

厦门是我国东南沿海的一颗璀璨明珠．这座顶着“中国最温馨城市”、“国际花园城市”、“联合国人居奖”等无数桂冠的现代化港口城市．让每个到过的人都深深折服于她的温馨和美丽。与之对应的是，厦门的工业总产值在特区建设25年中已增长146倍．在联合国发表的世界各国城市发展指标及发展前景统计报告中．被列为中国最具发展前途的25个城市之一．     

Stability Test for 2-D Continuous-Discrete Systems

Models of 2-D continuous-discrete systems are introduced, which can be used to describe some complex systems. Different from classical 2-D continuous systems or 2-D discrete systems, the asymptotic stability of the continuous-discrete systems is determined by Hurwitz-Schur stability (hybrid one) of 2-D characteristic polynomials of the systems. An algebraic algorithm with simpler test procedure for Hurwitz-Schur stability test of 2-D polynomials is developed. An example to illustrate the applications of the test approach is provided.     

Oxfordian (Jurassic) mayaitid (ammonite) dispersal in the Tibetan Himalaya as the first signal of the establishment of the Indo-Austrai subrealm

New fossil collections in the Lanongla area, Tibetan Himalaya enables the establishment of the Upper Jurassic ammonoidsuccession. Middle Oxfordian ammonite-fauna is characterized by endemic epimayaittds with a marine deepening event, suggesling a high stand of sea Ievel in the Tibetan Himalaya. Distribution of mayaitids around the Eastern Gondwana can be regarded as the first signal of the Indo-AustraI Subrealm that was progressively established during the Late Jurassic and Early Cretaceous times.     

试点国家实验室建设成效

2000年,科技部针对当前科技发展日益呈现学科交叉和综合的趋势,适应科技发展需要,提出了建设较大规模、学科交叉的国家实验室的思路,并开展了试点工作,在中科院沈阳金属所原有2个国家重点实验室和1个中科院重点实验室基础上,启动筹建了沈阳材料科学国家(联合)实验室,希望通过整     

CONVERGENCE PROPERTIES OF PROJECTED GRADIENT METHODS WITH NONMONOTONIC BACK TRACKING TECHNIQUE FOR CONVEX CONSTRAINED OPTIMIZATION

1. IntroductionGiven some function f(x): Wu - FI over a nonempty closed set n C W", one is interestedin solving the fOllowing optimization problem with constraints amin f(x)s.t. x E n (1.1)where f(x): Q C Wu - FI is twice continuously differentiable. This problem has receivedconsiderable attention extensively. The linear constrained case where n is a polyhedron is ofspecial inferest. Recently, there are quite a few articles proposing projected gradient methodsto solve the problem (see, fo…     

ON ASYMPTOTIC FORMULAE OF EIGENVALUE COUNTING FUNCTIONS OF LAPLACIAN ON AN UNBOUNDED DOMAIN WITH A FRACAL BOUNDARY

1. IntroductionLet D be an unbounded open set in R"(n 2 2) with finite Lebesgue measure. We considerthe following eigenvalue problem on a.where A = Z:=, 6 denotes the Laplacian on a and r ~ oa, the boundary of g. In thispaper we have a special interest in r which is considerably irregular like a fractal.Let N(A) denote the eigenvalue counting function of (P): the number of eigenvalues notexceeding A. When n is a bounded open set, it is well known that Weyl's classical asymptoticformulae f…     

Biological records of paleoclimate and paleoenvironment changes from Guanzhong area, Shaanxi Province during the last glacial maximum

We have collected a suite ofPaleoloxodon naumanni-Coelodonta antiquitatis fossils from a river terrace profile between Xi’an and Xianyang cities in Guanzhong Area, Shaanxi Province. A detailed examination of the fossils, together with¹⁴C determinations and pollen analyses, have enabled us to reconstruct preliminary features of climate and environment changes and their evolutionary processes, within the last glacial maximum (LGM): about 20 ka ago, the climate was basically cool and wet, and was favourable for the existence ofPaleoloxodon naumanni-Coelodonta antiquitatis fauna. This was followed by a cold, dry phase which was no longer suitable for this type of faunal suite, causing the death of a large number of mammalian assemblages. The available evidence indicates the existence of cold-dry and cool-wet climate and environment fluctuations during the LGM. The cool-wet stage within the LGM reflects a Heinrich event occurring in the high latitude areas, proving the existence of a teleconnection between polar-high latitude areas and the Loess Plateau.     

STABILITY FOR LINEAR NEUTRAL DIFFERENTIAL DIFFERENCE SYSTEMS

Liapunov functionals of simple form have been used to de-rive new sufficient conditions for uniform asymptotic stability of the zero so-lution of linear neutral differential difference systems.