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Differential AR algorithm for packet delay prediction

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Progress in Natural Science:Materials International 2006年第4期16卷 437-440页

作者： JIAO Liangbao, ZHANG De and BI Houjie institute of Acoustics, State Key Laboratory of Modern Acoustics, nanjing University, nanjing 210093, china institute of Communication Technique, nanjing University, nanjing 210093, china institute of Acoustics State Key Laboratory of Modern Acoustics Nanjing University Nanjing 210093 China institute of Communication Technique Nanjing University Nanjing 210093 China

Different delay prediction algorithms have been applied in multimedia communication, among which linear prediction is attractive because of its low complexity. AR (auto regressive) algorithm is a traditional one with low computation cost, while NLMS (normalize least mean square) algorithm is more precise. In this paper, referring to ARIMA (auto regression integrated with moving averages) model, a differential AR algorithm (DIAR) is proposed based on the analyses of both AR and NLMS algorithms. The prediction precision of the new algorithm is about 5-10 db higher than that of the AR algorithm without increasing the computation complexity. Compared with NLMS algorithm, its precision slightly improves by 0.1 db on average, but the algorithm complexity reduces more than 90% . Our simulation and tests also demonstrate that this method improves the performance of the average end-to-end delay and packet loss ratio significantly.

关键词： AR algorithm NLMS algorithm differential AR algorithm ARIMA model.

Nature　reserve　construction　and　its　contribution　to　the　biodiversity　conservation　in　china　mainland

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Journal of Environmental Sciences 1996年第1期8卷 15-20页

作者： Jiang Mingkang Xue Dayuan(nanjing institute of Environmental Science, National Environmental Protection Agency, nanjing 210042,china ) nanjing Inst Envmtl Sci National Envmtl Protection Agency Nanjing China China

By the end of 1993, 763 nature reserves were established in china with a total area of 66184.1 kha, occupied proximally 6. 84% of the whole country's land *** reserves concerning biodiversity conservation include ecosystem categories of forest, grassland, desert, terrestrial wetland and waters, ocean and coast and categories of wild animal and wild plant. Based on the construction of the reserves, the contributions of the reserves of various categories to the biodiversity conservation and the existed shortages for the reserve construction in china were analyzed thoroughly in this paper.

关键词： nature reserve protected area reserve construction biodiversity conservation.

Effects of free iron oxyhydrates and soil organic matter on copper sorption-desorption behavior by size fractions of aggregates from two paddy soils

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Journal of Environmental Sciences 2009年第5期21卷 618-624页

作者： WANG Fang, PAN Genxing, LI Lianqing institute of Resource, Ecosystem and Environment of Agriculture, nanjing Agricultural University, nanjing 210095, china. institute of Resource Ecosystem and Environment of Agriculture Nanjing Agricultural University Nanjing 210095 China

Effects of free iron oxyhydrates （Fed） and soil organic matter （SOM） on copper （Cu^2＋） sorption-desorption behavior by size fractions of aggregates from two typical paddy soils （Ferric-Accumulic Stagnic Anthrosol （Soil H） and Gleyic Stagnic Anthrosol （Soil W）） were investigated with and without treatments of dithionite-citrate-bicarbonate and of H2O2. The size fractions of aggregates were obtained from the undisturbed bulk topsoil using a low energy ultrasonic dispersion procedure. Experiments of equilibrium sorption and subsequent desorption were conducted at soil water ratio of 1：20, 25℃. For Soil H, Cu^2＋ sorption capacity of the DCB-treated size fractions was decreased by 5.9% for fine sand fraction, by 40.4% for coarse sand fraction, in comparison to 2.9% for the bnlk sample. However, Cu^2＋ sorption capacities of the H2O2-treated fractions were decreased by over 80% for the coarse sand fraction and by 15% for the clay-sized fraction in comparison to 88% for bulk soil. For Soil W, Cu^2＋ sorption capacity of the DCB-treated size fraction was decreased by 30% for the coarse sand fraction and by over 75% for silt sand fraction in comparison to 44.5% for the bulk sample. Cu^2＋ sorption capacities of the H2O2-treated fractions were decreased by only 2.0% for the coarse sand fraction and by 15% for the fine sand fraction in comparison to by 3.4% for bulk soil. However, Cu^2＋ desorption rates were increased much in H2O2-treated samples by over 80% except the clay-sized fraction （only 9.5%） for Soil H. While removal of SOM with H2O2 tendend to increase the desorption rate, DCB- and H2O2-treatments caused decrease in Cu^2＋ retention capacity of size fractions, Particularly, there hardly remained Cu^2＋ retention capacity by size fractions from Soil H after H2O2 treatment except for clay-sized fraction. These findings supported again the dominance of the coarse sand fraction in sorption of metals and the preference of absorbed metals bound to SOM in differently stabilized

关键词： paddy soils Cn^2+ sorption-desorption soil organic matter free iron oxyhydrates size fraction of aggregates

Annual precipitation fields secular variation over global land areas for 1948—2000

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Chinese Science Bulletin 2003年第3期48卷 281-286页

作者： SHI Neng & CHEN Luweng Department of Atmospheric Sciences, nanjing institute of Meteorology, nanjing 210044, china Department of Atmospheric Sciences Nanjing Institute of Meteorology Nanjing 210044 China

The secular variation over the global land an-nual precipitation (GLAP) fields for 1948—2000 is investi-gated. Evidence suggests that the GLAP abruptly reduced around 1978 and experienced a decrease of 0.54 mm/a, on average. Fuzzy clustering is used to group the annual pre-cipitation over commonly-used 36 latitudes belts into six belts for examining its secular variation. The results show that, except northern high-latitudes (60°—90°N) where it is slightly increased, the precipitation is decreased, especially in 35°N—35°S, and the diminution is the maximum of 0.98 mm/a at tropics. Moreover, identification of 1948—2000 flood/drought years on a global basis is made, showing no-ticeable interdecadal variations. During the years of warm (cold) events the precipitation decreases (increases) by 15.4 mm (14.4 mm) per year, on average. It can be assumed that global warming and frequent ENSO occurrences from the end of the 1970s maybe serve as the root cause of the dimi-nution.

关键词：全球降水长期变化年降水 ENSO 陆地 1948-2000年

A Primal-dual Neural Network for Shortest Path Problem

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计算机工程 2002年第S1期28卷 58-61页

作者： WANG ZeyanGU Hongfanginstitute of Sciences, PLAUST, nanjing 210016, china institute of Sciences PLAUST Nanjing 210016 China

The shortest path (SP) problem is a classical combinatorial optimization problem which plays an important role in a packet-switched computer and communication network.A new primal-dual neural network to solve the shortest path problem (PDSPN) is presented in this paper. The proposed neural network combines many features such as no network coefficients set,easy implementation in a VLSI circuit, and is proved to be completely stable to the exact solutions. The simulation example shows its efficiency in finding the "optimum" path(s) for data transmission in computer and communication network. ;;

关键词： Shortest pathPrimal-dualNeural networkOptimization

FOSSIL HAGLIDAE(ORTHOPTERA)IN china

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Science china Chemistry 1982年第10期29卷 1118-1132页

作者：洪友崇 Tianjin institute of geology and mineral resources Ministry of Geology

The present paper discusses Haglidae (Orthoptera) and its stratigraphic and geographicdistributions in china. Basing on our fossil specimens and the known fossil records of insectsthe author tries to discuss the taxonomy of the family Haglidae, including its subfamilies andgenera. Four new genera and seven new species are established.

关键词： Cu FOSSIL HAGLIDAE ORTHOPTERA)IN china length

Constraints of authigenic carbonates on trace elements (Sr,Mg) of lacustrine ostracod shells in paleoenviron-ment reconstruction and its mechanism

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Science china Earth Sciences 2008年第5期51卷 654-664页

作者： HU Guang1,2, JIN ZhangDong1 & ZHANG Fei3 1 State Key Laboratory of Loess and Quaternary geology, institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, china 2 Graduate University of the Chinese Academy of Sciences, Beijing 100049, china 3 College of resources and Environmental Science, nanjing Agricultural University, nanjing 210095, china State Key Laboratory of Loess and Quaternary geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China Graduate University of the Chinese Academy of Sciences Beijing China College of resources and Environmental Science Nanjing Agricultural University Nanjing China

Molar ratios of Mg/Ca and Sr/Ca were measured in two species of ostracod shells preserved in the upper core (15–55 m) of the Hequing Basin in Yunnan Province, southwest china. By correlating the molar ratios between Mg/Ca and Sr/Ca and comparing them with Sr concentrations of the sediments, we suggested that: (1) the molar Mg/Ca and Sr/Ca ratio variations in respective ostracod primo reflected the changes in its ambient water composition and ecology; (2) the molar Sr/Ca ratios responded better to the salinity change linearly than Mg/Ca without aragonite precipitation in the system, and otherwise there was no linear relation between them; and (3) the molar Sr/Ca ratios were mainly controlled by salinity and authigenic carbonate precipitation, whereas the molar Mg/Ca ratios were related to both salinity and temperature. In fact, the rate of ostracod growth owing to temperature controls the fluctuation of Mg/Ca in shells. Here, more attentions should be paid to the constraint of authigenic mineral precipitation processes on the trace elements in ostracod shells and to the correlation between these trace elements in biogenic carbonates and compositions of the sediments in systems and in future in vitro experiments.

关键词： ostracod shell molar Sr/Ca ratio molar Mg/Ca ratio environmental response Heqing Basin

Genesis and district mineralization model of lead-zinc deposits from the eastern margin of Kangdian axis

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Chinese Science Bulletin 1999年第S2期44卷 74-77页

作者： GUAN Shiping and LI Zhongxiong Chengdu institute of geology and mineral resources, Chengdu 610082, china Chengdu institute of geology and mineral resources Chengdu 610082 China

SITUATED on the eastern margin of Kangdian axis the lead-zinc mineral belt is an important mineral occur- rence of lead-zinc in southwestern china. It is 1 200 km in length from Kangding in Sichuan Province tonortheastern Yunnan Province, and 500 km in width from west to east. There are four large deposits,fourteen middle deposits and many small deposits or mineralized spots. Famous large deposits such as Doliangzi, Tianbaoshan, Chipu and Kuangshanchang are distributed in this belt. 1 Geological setting There are many mineral-bearing strata in carbonate-hosted lead-zinc deposits of this mineral belt,such as Dengying formation （Zbdn）, Longwangmiao formation （2 l） Erdaoshui formation （ 3 e ）,Daqing formation（O2 d ）, Daguan formation （S2d ）, the lower Devonian and Baizuo formation （ C1 b）.

关键词： genesis district mineralization model lead-zinc deposits Kangdian axis.

CH_4-rich fluid inclusions in the Yushigou mantle peridotite and their implications, North Qilian Mountains, china

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Chinese Science Bulletin 1999年第21期44卷 1992-1995页

作者： SU Li, SONG Shuguang and WANG ZhihaiXi’an institute of geology and mineral resources, CAGS, Xi’an 710054, china Xi’an institute of geology and mineral Rrsources CAGS Xi’an China

Studies were carried out on the early phase of fluid inclusions which occur in residual olivines in harzburgite from the Yushigou ophiolitic mantle peridotite, the North Qilian Mountains. Components of these inclusions, analyzed by micro laser Raman spectroscopy, are dominantly CH4 (70%-95%) with minor H2, N2, H2S,CO2,C2H4,C2H6, and C3H6, but

关键词： CH4-rich fluid mantle peridotite North Qilian Mountains.