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Decoding algorithms for shortened-extended turbo product codes in WiMAX systems

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Science in china(Series F) 2009年第12期52卷 2415-2423页

作者： XU ChangLong1,3,4, YANG Wei1,2 & YE WeiChen4 1 State Key Laboratory of Networking and Switching technology, beijing University of Posts and Telecommunications, beijing 100044, china 2 State Key Laboratory of Rail Traffic Control and Safety, beijing Jiaotong University, beijing 100044, china 3 National Mobile Communications research Laboratory, Southeast University, Nanjing 210096, china 4 Intel corporation, beijing Kerry Center, Guanghua Road 1, beijing 100020, china State Key Laboratory of Networking and Switching technology Beijing University of Posts and Telecommunications Beijing China National Mobile Communications research Laboratory Southeast University Nanjing China Intel corporation Beijing Kerry Center Beijing China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing China

The component codes of turbo product codes in WiMAX systems are extended Hamming codes and single parity check codes as well as their shortened forms, In this paper, three novel iterative decoding algorithms based on Chase, MAP algorithms and their combination are proposed for shortened-extended turbo product codes. The iterative decoding algorithm based on Chase algorithm is proposed to reduce the decoding complexity without any performance loss. An efficient MAP algorithm is then proposed to decode the component codes of shortened single parity check codes and shortened-extended Hamming codes. A comprehensive performance comparison of the proposed decoding schemes is conducted for three typical classes of turbo product codes in WiMAX OFDMA systems. The suitable decoding algorithms are recommended for different classes based on the simulation results.

关键词： block code product code iterative decoding

Theory Analysis and Experiment Investigation of Laser Shock Processing on Titanium Alloy Blade

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稀有金属材料与工程 2011年第S4期40卷 235-239页

作者： Che Zhigang1,Gong Shuili1,Cao Ziwen1,Zou Shikun1,Gao Yu2,Ma He1 1Laboratory of Science and technology on Power Beam Processes,beijing Aeronautical Manufacturing technology research institute,Bei-jing 100024,china 2Shenyang Liming Aero-Engine Group corporation Ltd.,Shenyang 110043,china beijing Aeronaut Mfg Technol Res Inst Lab Sci & Technol Power Beam Proc Beijing 100024 Peoples R China Shenyang Liming Aeroengine Grp Corp Ltd Shenyang 110043 Peoples R China

Laser shock processing (LSP) is an effective surface treatment technology to increase the resistance of metallic components to high-cycle fatigue (HCF),stress corrosion cracking (SCC),wear,etc.,through imparting compressive residual stress on the *** requirement for aeroengine blade treatment and the principle of LSP were introduced at the beginning of this *** key theories and technologies for LSP were analyzed,including improving the pressure model and introducing the technique of eliminating wave reflection at the back of blade during *** nanocrystallation of titanium alloy surface was realized for the first time using the method of laser shocking at the same time no impurity particles were *** treating one kind of aeroengine blade using LSP,the technology parameters were *** nature frequency,fatigue life and residual stress were *** results showed the blade performance was improved obviously,which established the theory and experiment base of laser shock processing on blisk.

关键词： laser shock processing pressure model nanocrystallation natural frequency titanium alloy

High-Resolution Transgressive-Regressive Sequence Stratigraphy of Chang 8 Member of Yanchang Formation in Southwestern Ordos Basin,Northern china

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Journal of Earth Science 2010年第4期21卷 423-438页

作者：吕明胜陈开远薛良清衣丽萍朱红涛 research institute of Petroleum Exploration & Development PetroChina School of Energy Resources China University of Geosciences china National Oil and Gas Exploration and Development corporation Faculty of Earth Resources China University of Geosciences

The reservoirs within the Chang 8 Member of Yanchang(延长) Formation in the southwestern Ordos basin are characterized by low *** is significant to build a high-resolution sequence stratigraphic framework for the exploration and development of these *** on an integrated investigation of well logs,seismic data,cores and outcrops,the Chang 8 Member is interpreted as a 3rd-order transgressive-regressive(T-R) sequence,which consists of six 4th-order T-R sequences,namely,K1,K2,K3,K4,K5 and K6,respectively,from base to *** 4th-order sequence comprises a transgressive systems tract overlain by a regressive systems *** K1 to transgressive systems tract of K4,it is characterized by the landward shifts of facies and overall retrogradational sequence stacking pattern due to accommodation increase more than sediment supply during the 3rd-order base-level *** distributary channels are mainly deposited in the transgressive systems tracts,and the interdistributary bays,sheet sands,and small-scale mouth bars are primarily developed in the regressive systems tracts in response to the 4th-order base-level *** the regressive systems tracts of K4 to K6,it is characterized by the basinward shifts of facies and overall progradational sequence stacking pattern because of accommodation increase less than sediment supply during a fall in 3rd-order base *** distributary channels are mainly accumulated in the transgressive systems tracts,and distributary channels and mouth bars are deposited in the regressive systems tracts as a result of the 4th-order base-level *** stratigraphic and sedimentological analyses indicate that sequences K1,K2,K5 and K6,as well as the basin edge of K3 and K4,remain potential for exploration and development due to their high reservoir quality in response to the low accommodation and more sediment supply.

关键词： transgressive-regressive sequence base level sediment supply sequence stratigraphic framework Ordos basin.

A kind of coccoid dinoflagel-lates-like fossils gives a new explanation of source of dinosterane in the Early-Middle Cambrian

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Chinese Science Bulletin 2001年第5期46卷 420-423,442页

作者： BIAN Lizeng, ZHANG Shuichang, ZHANG Baomin, MAO Shaozhi & YIN LeimingDepartment of Earth Sciences, Nanjing University, Nanjing 210093,china Key Laboratory of Petroleum Geochemistry, china National Petroleum corporation, beijing 100083, china research institute of Petroleum Exploration and Development, china National Petroleum corporation, beijing 100083, china china University of Geosciences, beijing 100083, china Nanjing institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, china Department of Earth Sciences Nanjing University Nanjing China Key Laboratory of Petroleum Geochemistry China National Petroleum Corporation Beijing China research institute of Petroleum Exploration and Development China National Petroleum Corporation Beijing China china University of Geosciences Beijing China Nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China

The coccoid fossils covered with thick gelatinous envelop containing several gametes are discovered in gyps and salt deposits of Cambrian, H4 well and chert bed of the base of Yuertus Formation (∈11) of Xiaoerbulake Section. The fossils are described and compared with coccoid dinoflagellates. These fossils may be a coccoid life-cycle stage (vegetative cyst) of coccoid dinoflagellates. If this identification is correct, the coccoid dinoflagellates-like fossils could give a reasonable explanation of the dinoflagellate-specific biomarkers from Cambrian, H4 well, Tarim Basin.

关键词： coccoid dinoflagellates-like fossils dinoflagellate-specific biomarkers Cambrian Tarim Basin.

The productivity evaluation model and its application for finite conductivity horizontal wells in fault block reservoirs

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Petroleum Science 2010年第4期7卷 530-535页

作者： Jiang Hanqiao Ye Shuangjiang Lei Zhanxiang Wang Xing Zhu Guojin Chen Minfeng Key Laboratory of Petroleum Engineering Ministry of Education China University of Petroleum Beijing 102249 China research institute of Petroleum Exploration and Development PetroChina Beijing 100083 China research institute of china National Offshore Oil corporation Beijing 100027 China

It is very difficult to evaluate the productivity of horizontal wells in fault block reservoirs due to the influence of fault *** the basis of the method of images and source-sink theory,a semianalytical model coupling reservoir and finite conductivity horizontal wellbore flow dynamics was built,in which the influence of fault sealing was taken into *** distribution of wellbore flow and radial inflow profiles along the horizontal interval were also *** impact of the distance between the horizontal well and the fault on the well productivity was quantitatively *** on this analysis,the optimal distance between the horizontal well and the fault in banded fault block reservoirs could be *** to the field application,the relative error calculated by the model proposed in this paper is within ±15%.It is an effective evaluation method for the productivity of horizontal wells in fault block *** productivity of the horizontal well increases logarithmically as the distance between the horizontal well and the fault *** optimal distance between the horizontal well and the fault is 0.25-0.3 times the horizontal well length.

关键词： Fault block reservoir horizontal well finite conductivity productivity evaluation well location design

TOLUENE HYDROXYLATION WITH H2O2 CATALYZED BY TITANIUM SILICALITE（TS-1）

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Chinese Journal of Catalysis 1998年第2期 6-7页

作者： Yang Wubin, Liu Xiyao*(research institute of Yanshan Petrochemical corporation, beijing 102549)

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ＴＯＬＵＥＮＥＨＹＤＲＯＸＹＬＡＴＩＯＮＷＩＴＨＨ２Ｏ２ＣＡＴＡＬＹＺＥＤＢＹＴＩＴＡＮＩＵＭＳＩＬＩＣＡＬＩＴＥ（ＴＳ１）ＹａｎｇＷｕｂｉｎ，ＬｉｕＸｉｙａｏ（ＲｅｓｅａｒｃｈＩｎｓｔｉｔｕｔｅｏｆＹａｎｓｈａｎＰｅｔｒｏｃｈｅｍｉｃａｌＣｏｒ...

关键词： Titanium silicalite (TS1) Toluene Hydroxylation Cresol

An analysis of soil composition and mechanical properties of riverbanks in a braided reach of the Lower Yellow River

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Chinese Science Bulletin 2008年第15期53卷 2400-2409页

作者： XlA JunQiang WU BaoSheng WANG YanPing ZHAO shougang State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China Yellow River institute of Hydraulic research YRCC Zhengzhou 450003 China

The channel adjustment in a braided reach is very prominent in the fluvial processes of the Lower Yel-low River, in which the process of bank erosion plays an important role, especially during the period of clear water scouring. The process of bank erosion is closely related to soil composition and mechani-cal properties of the riverbanks. In this paper, the recent bank erosion process in a braided reach be-tween Huayuankou and Gaocun was firstly investigated after the water impoundment and sediment detention of the Xiaolangdi Reservoir, and then a field observation and indoor soil tests were con-ducted at 10 typical riverbanks in the braided reach. Through analyzing the experimental results, changes of riverbank-soil composition and mechanical properties were found, and the two real reasons causing serious bank erosion in the braided reach were identified. The following conclusions were drawn from this study: (i) the majority of riverbanks are made up of cohesive soil, and can be charac-terized by obvious vertical stratification structures of soil composition; (ii) these riverbanks are very erodible due to the lower clay-content and weak erosion-resistant strength in the bank soil, with its critical shear stress value (0.1―0.3 Pa) being much less than that of the average near-bank flow shear stress (2.0―3.0 Pa), which is one important reason causing serious bank erosion; (iii) frequent occur-rence of bank failure during flood seasons usually results from the fact that the values of shear strength parameters such as the cohesion and internal friction angle decrease with the increase of water content in riverbank soil, and the value of cohesion reduces drastically from 34 to 4 kPa with the increase of water content, which is another important reason causing serious bank erosion in the braided reach.

关键词：黄海土壤分析河堤侵蚀化学物质

A new type of Shipboard Meteorological Satellite Receiving-processing System

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Acta Oceanologica Sinica 2000年第1期19卷 35-46页

作者： Xie Simei Hao Chunjiang Zou Bin Jing Qiyi Liao Xiaohong Sheng Xiaowen Zhang Canrong (1. National research Center for Marine Environment Forecasts, beijing 100081, china 2, Second institute of china Aerospace corporation 3. beijing Chuanyi Electric Compan Natl. Res. Ctr. Mar. Environ. F. Beijing 100081 China Second Inst. of china Aerosp. Corp. China beijing Chuanyi Electric Company Chinese Academy of Sciences Beijing China

The Shipboard Meteorological Satellite Receiving-processing System (SMSRPS) is specially developed for the navigation meteorological safeguard of the Antarctic exploration ship over the sea ice area of the forth Ocean. This system can suit to the climate environment of very high temperature high moisture and very low temperature - supersaturation; it has a self-protection ability to against the hurricane - force wind over force 12 and the strong vibration during icebreaking, as well as strong magnetic disturbance. It has two sets of receiving-imagery processing systems for polar orbit low-resolution and quasi-stationary high-solution satellites. The key creation Points of this system are as follows: 1. the active gyro-control stabilization platform and a mixed mounting system of three rotating a - B and x -- y axes are used. It solved the tracing difficulties both in the low elevation angle and very high elevation angle of polar-orbit satellite, even in the status of ship moving with continuously changing its poition, direction and ship roll and pitch. 2. Imagery processing subsystem. The newest BORLAND-- DELPHI language and PASCAL language pro gramming software are used under WINDOWS 95 environment. It has a dynamic positioning nested-grid system and electric mapping grid data system. It can show the latitude-longitude of any point on the map, and marks any object such as ship, station or island, and draws the route. It can monitor cloud and temperature, forest fire, anomalous change of ocean and land. It can output satellite cloud maps of 24 bit with very high clarity. This system is very advanced in technique for the whole structure with the features of small volume, light weight and very low cost. It suits to very bad climate and ocean environment. Its imagery process ing system has complete functions with high resolution and being very easy to operate. It is not only suit to land use, but also and specially to all kinds of ship over the sea. It can be exte

关键词： Shipboard Meteorological Satellite Receiving-processing System imagery processing system active gyro-control platform

SYNTHESIS OF CERIUM-CONTAINING HIGH SILICA ZEOLITES New Catalysts for Hydroxylation of Phenol

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Chinese Journal of Catalysis 1997年第3期 12-13页

作者： Guo Hongchen *, Wang Xiangsheng (institute of Industrial Catalysts, Dalian University of technology, Dalian 116012) Zou Bensan (research institute of Yanshan Petrochemical corporation, beijing 102550)

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关键词： Cerium Incorporation High silica zeolite Hydroxylation Phenol