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数字卫星通信中的Viterbi算法及DSP实现

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现代电子技术 2003年第2期26卷 31-33页

作者：董鹏张锁熊田迎举郑州大学信息工程学院河南郑州450052 信息产业部二十七研究所河南郑州450005 郑州空管中心河南郑州450003

介绍了应用于数字卫星通信的 Viterbi (维特比 )译码算法 ,讨论了影响编码增益的几个参数 ,提出了用 TI(德州仪器 )公司 TMS32 0 C5.4

关键词：数字卫星通信 DSP Viterbi算法蝶形运算单元距离度量回溯深度 CCSU

柯坪地区中下寒武统走滑断裂带方解石脉期次、古流体演化与油气充注历史

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地球科学 2023年第6期48卷 2189-2203页

作者：刘建章陈诚蔡忠贤李杰吴正洲中国地质大学构造与油气资源教育部重点实验室湖北武汉430074 中国地质大学资源学院湖北武汉430074 中国石油化工股份有限公司江汉油田分公司采气一厂重庆404120

新疆柯坪地区野外露头中下寒武统走滑断裂带充填多期方解石脉和固体沥青,是揭示流体活动和油气成藏过程的重要媒介.在野外露头断裂带中方解石脉、沥青充填特征观察的基础上,利用岩石薄片、阴极发光、微区原位稀土元素、碳氧同位素及流... 详细信息

新疆柯坪地区野外露头中下寒武统走滑断裂带充填多期方解石脉和固体沥青,是揭示流体活动和油气成藏过程的重要媒介.在野外露头断裂带中方解石脉、沥青充填特征观察的基础上,利用岩石薄片、阴极发光、微区原位稀土元素、碳氧同位素及流体包裹体等测试技术,厘定方解石脉形成期次、成脉流体性质及来源,揭示成脉古流体演化及其与油气充注的耦合关系.结果表明,柯坪地区中下寒武统走滑断裂中发育4~5.方解石脉(C1、C2、C3、C4、C5.;C1成脉流体为地层水,部分混合了上覆阿瓦塔格组地层卤水;C2、C3成脉流体主要为地层水与含烃热液流体的混合,但C3成脉温度稍低;C4成脉流体也主要为地层水,存在大气淡水的混合;C5.脉流体为地层水、含烃流体和大气淡水的混合.5.方解石脉分别形成于加里东中晚期、海西中晚期、印支-燕山中期、燕山晚期和喜马拉雅期,3期油气充注于海西中晚期、印支-燕山中期和喜马拉雅期.海西中晚期、印支-燕山中期可能是柯坪地区中下寒武统原生油气藏的主要形成时期,喜马拉雅期是原生油气藏破坏、调整和再聚集期.喜马拉雅期定型、与走滑断裂相关圈闭也具有优越成藏条件.

关键词：油气充注古流体演化方解石脉走滑断裂带柯坪地区石油地质.

Geochemical characteristics and origin of gases from the Upper,Lower Paleozoic and the Mesozoic reservoirs in the Ordos Basin,China

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Science China Earth Sciences 2008年第S1期51卷 183-194页

作者： HU AnPing 1 ,Li Jian 2 ,ZHANG WenZheng 3 ,LI ZhiSheng 2 ,HOU Lu 4 &LIU QuanYou 5.1 Department of Earth Sciences,Zhejiang University,Hangzhou 310027,China 2 Langfang Branch,Reasearch Institute of Petroleum Exploration and Development,PetroChina,Langfang 065.07,China 3 Institute of Exploration and Development,PetroChina Changqing Oilfield company,Xi’an 710021,China 4 University of Petroleum,Beijing102249,China 5.PetroChina Research Institute of Petroleum Exploration and Development,Beijing 100083,China Department of Earth Sciences Zhejiang University Hangzhou China Langfang Branch Reasearch Institute of Petroleum Exploration and Development PetroChina Langfang China Institute of Exploration and Development PetroChina Changqing Oilfield Company Xi’an China University of Petroleum Beijing China PetroChina Research Institute of Petroleum Exploration and Development Beijing China

The Ordos Basin,the second largest sedimentary basin in China,contains the broad distribution of natural gas *** far,several giant gas fields have been discovered in the Upper and Lower Paleozoic in this basin,each having over 1000×10 8 m 3 of proven gas reserves,and several gas pools have also been discovered in the *** paper collected the data of natural gases and elucidated the geochemical characteristics of gases from different reservoirs,and then discussed their *** hydrocarbons preserved in the Upper Paleozoic,the elevatedδ13C values of methane,ethane and propane indicate that the gases would be mainly coal-formed gases;the singular reversal in the stable carbon isotopes of gaseous alkanes suggests the mixed gases from humic sources with different *** the Lower Paleozoic,theδ13C 1 values are mostly similar with those in the Upper Paleozoic,but theδ13C 2 andδ13C 3 values are slightly lighter,suggesting that the gases would be mixing of coal-type gases as a main member and oil-type *** are multiple reversals in carbon isotopes for gaseous alkanes,especially abnormal reversal for methane and ethane(i.e.δ13C 1 >δ13C 2 ),inferring that gases would be mixed between high-mature coal-formed gases and oil-type *** the Mesozoic,the δ13Cvalues for gaseous alkanes are enriched in 12C,indicating that the gases are mainly derived from sapropelic sources;the carbon isotopic reversal for propane and butane in the Mesozoic is caused by microbial oxidation and mixing of gases from sapropelic sources with different *** contrast to the Upper Paleozoic gases,the Mesozoic gases are characterized by heavier carbon isotopes of iso-butane than normal butane,which may be caused by gases generated from different kerogen types. Finally,according toδ13C 1 -Ro relationship and extremely low total organic carbon contents,the Low Paleozoic gases would not be generated from the Ordovician source as a main gas source,bycontrast, the Upper Pale

关键词： Ordos Basin natural gas chemical composition carbon isotope genesis

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下肢静脉顺行造影(附80侧分析)

实用放射学杂志 2001年第11期17卷 850-851页

作者：杨文杰杨岩白民学中国长城铝业公司总医院放射科中国长城铝业公司总医院放射科河南郑州45.041

目的　探讨下肢静脉顺行造影X线表现。方法　回顾性分析 80侧下肢静脉顺行造影的影像学所见。结果　综合影像学所见 ,将病人分为正常组和异常组 ;其中异常组分单纯性瓣膜关闭不全 4侧 ,交通静脉瓣膜关闭不全 6侧 ,原发性下肢深静脉瓣膜... 详细信息

目的　探讨下肢静脉顺行造影X线表现。方法　回顾性分析 80侧下肢静脉顺行造影的影像学所见。结果　综合影像学所见 ,将病人分为正常组和异常组 ;其中异常组分单纯性瓣膜关闭不全 4侧 ,交通静脉瓣膜关闭不全 6侧 ,原发性下肢深静脉瓣膜关闭不全 32侧 ,继发性下肢深静脉瓣膜关闭不全 5. ,血栓形成 3侧 ,先天性下肢静脉发育异常 2侧 ,静脉瘤样或弥漫血管湖 5.。结论　下肢静脉顺行造影作为一种简便易行的检查手段在下肢静脉疾病的诊断中具有独特的应用价值。

关键词：静脉造影下肢静脉瓣功能不全

Comprehensive Control on Microstructures and Properties of Medium Carbon V-N Microalloyed Steel Seamless Oil-Well Tubes of Hot-Rolling Non-Quenched/Tempered

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Comprehensive Control on Microstructures and Properties of M...

Temperature-pressure Comprehensive Adsorption Model for coal Adsorption of Methane

第六届国际低合金高强度钢会议

作者： LIU Sheng-xin~(1,2),LIU Guo-quan~2,CHEN Yong~1,ZHANG Yong-gang~3, HUANG Jian-kai~3 (1.School of Materials Science and Engineering,zhengzhou University.zhengzhou 45.002,Hennan China 2.School of Materials Science and Engineering.University of Science and Technology Beijing.100083,China 3.Wuxi Seamless Steel Tube company Ltd,Wuxi 214026.Jiangsu China)

＜正＞The relationship between microstructures and mechanical properties of a medium carbon V-N microalloyed steel used for N80 seamless oil-well tubes of hot rolling non-quenched/tempered（non-Q and T）was *** results have shown that volume percentages of upper bainite,modified bainite and ferrite have a decisive influence on impact energies of steel *** the total volume percentage of bainite is larger than 5.,the impact energy of tubes can not satisfy with the industrial ***,if the total volume percentage of bainite is smaller than 5..then the impact energy of steel tubes enhances with volume percentage of ferrite *** final microstructures have closely relation with tube billet quality,controlled cooling temperature after tube rolling and cooling method after *** quality of medium carbon V-N microalloyed steel for non-Q and T oil-well tubes can be produced through comprehensive control of microstructures and mechanical properties in sub-procedures,especially for tube billet quality and controlled cooling parameters.

关键词： medium carbon V-N microalloyed steel N80 grade seamless oil-well tube microstructure mechanical property

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Temperature-pressure Comprehensive Adsorption Model for Coal...

MICROSTRUCTURE AND EROSION-CORROSION CHARACTERISTIC OF Ni-BASED COATINGS

The 9th International Symposium on CBM/CMM in China

作者： Zhang Qun~1,Cui Yongjun~2,Zhong Lingwen~1,Zhang Qingling~1, Jiang Wenping~1,LiI Yuhui~1 (1.Xi’an Branch,China coal Research Institute,Shaanxi 71005. 2.China Shenhua coal Liquefaction company Ltd.,Beijing 10001)

＜正＞A serious of representative rank coals with dark lignite,gas coal,coking coal,lean coal,anthracite and meta-anthracite were *** high pressure isothermal adsorption tests were made under different temperatures of 20,30,40,5.℃*** on adsorption potential theory,shape features of methane characteristic curves for coals were revealed.A new temperature-pressure comprehensive adsorption model of coal adsorption of methane（P -T adsorption mode for short） was deducted and established,and the method of calculating the characteristic constant for the model was *** use of a great number of experimental data from methane high pressure isothermal tests,the prediction results of the model were verified and compared with the prediction results of Langmuir isothermal adsorption *** is shown that the prediction results of the model are almost identical with the experimental data with mean relative deviations less than 5.and the model can accurately describe adsorption characteristics under combined action of temperature and pressure for all rank coals including extremely low-rank dark lignite and extremely high-rank *** model is proved correct and reasonable,and has more function and wider range than ones of Langmuir isothermal adsorption model.

关键词： coal methane absorption temperature-pressure comprehensive adsorption model

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MICROSTRUCTURE AND EROSION-CORROSION CHARACTERISTIC OF Ni-BA...

Formation mechanism of carbonate cemented zones adjacent to the top overpressured surface in the central Junggar Basin,NW China

第七届国际热喷涂研讨会（ITSS’2004）暨第八届全国热喷涂年会（CNTSC’2004）

作者： Zhang Anfeng, Zhang Junhu, Peng Feng ( School of Mechanical Engineering, Xi’an Jiaotong University, China) ( Shendong coal Limited company, Shaanxi, China)

In order to improve the service life of low-carbon steel in erosion-corrosion working condition, low-carbon steel (ASTM1020) was used as substrate, and stainless steel (AISI321) was applied to contrast test. Erosion-corrosion synergism and failure mechanism and electrochemical behavior was investigated systematically in liquid-solid duel-phase fluid (5. E2SO4 +15. silica sand). The results show as follows: (1) The corrosion resistance of Delelo5. and Ni60JH coatings is 16 and 30 times higher than that of the substrate respectively;The erosion-corrosion resistance of Delelo5. coatings is 3-5.times higher than that of the substrate;The erosion-corrosion resistance of Ni60JH coatings is 8-15.times higher than that of the substrate, and excels stainless steel slightly. (2) The weight loss rates of synergistic effects between erosion and corrosion of materials increase from 42-66% to 78-85. of the total weight loss rates when the erosion velocity increased from 5./s to 10m/s;In the pure corrosion medium, Ni60JH coatings and the stainless steel are uniform corrosion, but Delelo5. coatings and low-carbon steel are alternative corrosion. (3) In the erosion-wear process, the cutting and plowing are the main features for Ni60JH coatings, and that the plowing and plastic distorting are the main characters for Delelo5. coatings and two steels.

关键词： High velocity oxy-fuel (HVOF) Erosion and corrosion Synergism Liquid-solid duel-phase fluid

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Science China Earth Sciences 2010年第4期53卷 529-540页

作者： YANG Zhi1,2,ZOU CaiNeng1,3,HE Sheng2,LI QiYan1,HE ZhiLiang3,WU HengZhi5.CAO Feng1,MENG XianLong4,WANG FuRong2 & XIAO Qilin21 State Key Laboratory of EOR,Research Institute of Petroleum Exploration & Development,PetroChina,Beijing 100083,China 2 Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education,China University of Geosciences,Wuhan 430074,China 3 State Key Laboratory of EOR,Research Institute of Petroleum Exploration & Development,Petrochina,Beijing 100083,China 4 Research Institute of Petroleum Exploration and Production,SINOPEC,Beijing 100083,China 5.Southwest Branch company,SINOPEC,Chengdu 61005.,China State Key Laboratory of EOR Research Institute of Petroleum Exploration & Development PetroChina Beijing China Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education China University of Geosciences Wuhan China State Key Laboratory of EOR Research Institute of Petroleum Exploration & Development Petrochina Beijing China Southwest Branch company SINOPEC Chengdu China Research Institute of Petroleum Exploration and Production SINOPEC Beijing China

Carbonate cemented zones are normally adjacent to the top overpressured surface in the central Junggar Basin,NW *** carbon and oxygen isotopic compositions and petrological investigations of carbonate cements in the carbonate cemented zones indicate that:(1) carbonate cements are composed dominantly of ferrocalcite,ferroan dolomite,and ankerite;(2) carbonate cements are formed under a high temperature circumstance in the subsurface,and organic fluid migration has an important effect on the formation of them;and(3) carbon and oxygen ions in the carbonate cements migrate from the underlying overpressured *** suggests that the occurrence of carbonate cemented zones in this region results from multiple phases of organic fluid expulsion out of the overpressure compartment through geological *** study provides a plausible mechanism of the formation of carbonate cemented zones adjacent to the top overpressured surface in the clastic sedimentary basins,and has an important implication for understanding the internal correlation between the formation of carbonate cemented zones adjacent to top overpressured surface and geofluids expulsion out of overpressured system.

关键词： carbonate cemented zones formation mechanism stable carbon and oxygen isotopic top overpressured surface central Junggar Basin coal-bearing strata

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神经网络在洪水实时预报中的应用研究

水电能源科学 2002年第3期20卷 28-31页

作者：熊立华郭生练王元武汉大学水利水电学院湖北武汉430072 郑州黄河工程公司河南郑州450008

建立了一种基于神经网络的洪水实时预报模型。运用向后演算法 ,该模型的权重系数可以在每一时间步长上进行自动更新 ,较好地反映了实际水文过程和参数的时变性 ;由于该模型不再需要单独的误差序列实时校正模型 ,因而更加简洁。最后利用... 详细信息

建立了一种基于神经网络的洪水实时预报模型。运用向后演算法 ,该模型的权重系数可以在每一时间步长上进行自动更新 ,较好地反映了实际水文过程和参数的时变性 ;由于该模型不再需要单独的误差序列实时校正模型 ,因而更加简洁。最后利用淮河鲇鱼山水库 1 975. 1 999年的小时降雨和入库洪水资料对模型参数进行了率定和校核。结果表明 ,洪水实时预报的效率系数超过 96 % ,洪峰值合格率为 92 .5.% ,峰现时间误差都在 1

关键词：神经网络洪水实时预报实时校正向后演算法神经网络