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略论战国时期赵国对代地之经营 被引量:4
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作者 雷鹄宇 《邯郸学院学报》 2010年第4期43-46,共4页
代地原本是代戎活动的区域,战国时期一直处于赵国的治下。赵国对代地先后采用了设立封君、设置郡县、归边将统领以及流亡后成立代王国等统治方式,各种统治方式下赵国都给予代地相当大的自主权。这种策略总体上是成功的,使得代地为赵国... 代地原本是代戎活动的区域,战国时期一直处于赵国的治下。赵国对代地先后采用了设立封君、设置郡县、归边将统领以及流亡后成立代王国等统治方式,各种统治方式下赵国都给予代地相当大的自主权。这种策略总体上是成功的,使得代地为赵国成为军事强国发挥了重要作用。 展开更多
关键词 赵国 代地 代郡 统治方式
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《宋代地券书法精选》所收两方买地券校补
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作者 孙梦钰 《现代语文》 2023年第1期17-21,共5页
《宋代地券书法精选》收录了许多品相精良、艺术价值较高的宋代买地券拓片。由于某些原因,其释文存在着字形辨析有误、繁简混淆、正俗字不分、标点误断而造成词语不辞、文意不通等错误,直接影响到宋代地券材料的有效利用。综合运用文字... 《宋代地券书法精选》收录了许多品相精良、艺术价值较高的宋代买地券拓片。由于某些原因,其释文存在着字形辨析有误、繁简混淆、正俗字不分、标点误断而造成词语不辞、文意不通等错误,直接影响到宋代地券材料的有效利用。综合运用文字学、语言学、文献学等多学科知识,纠正《宋故郭氏夫人地券文》《宋故胡七娘地券》释文中所存在的错误,以期对宋代买地券的整理、研究与欣赏提供有益的借鉴。 展开更多
关键词 《宋代地券书法精选》 买地券 释文校读
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Progresses and future directions on yardangs
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作者 DING Zhaojing LAI Zhongping WANG Jiang 《地球环境学报》 CSCD 2024年第4期566-582,共17页
Background,aim,and scope Yardang is a kind of typical wind-eroded landform in arid zones both on Earth and other planets.Their geomorphic process records the surface changes and climate,which may play a vital role in ... Background,aim,and scope Yardang is a kind of typical wind-eroded landform in arid zones both on Earth and other planets.Their geomorphic process records the surface changes and climate,which may play a vital role in exploring the coupled landform-atmosphere system in arid zones.Recently,significant progresses have been made in this research field,and a review is still absent,which is the aim of the paper.Materials and methods Previous studies on the distribution,composition,morphology,and climatic driving force of yardang landform were reviewed.Results Earth yardang’s three evolutionary models were generalized:morphology evolution model,altitude evolution model and climate driven evolution model.Extraterrestrial yardang and its evolution are also summarized:the morphology is dominated by long ridges on Venus and Titan,and three yardang evolution hypotheses and an indirect dating method based on stratigraphic contact have been studied on Mars.Discussion In this study,firstly,the definition and morphology of yardang were described to define its characteristics.Secondly,we argue that yardang evolution has two dimensions:short-term variation and longterm variation.In the short-term variation,the morphological evolution of yardang on earth can be divided into four stages:embryonic stage,juvenile stage,mature stage,and demise stage.In the long-term variation,the evolution of yardang on earth is climate-driven,i.e.,it is controlled by atmospheric circulation changes during glacial-interglacial periods.Thirdly,yardang research on extraterrestrial bodies was also summarized:yardang has been found on Mars,Venus,and Titan,and the research focus by far are on geomorphology only.Conclusions(1)Yardang landform is an erosion landform with alternating ridges and troughs,with main form of whale back shape and fluctuations in the range of aspect ratios;(2)the short-term variation of yardang is manifested in its morphological evolution and height change,while the long-term variation is climate-driven;(3)based on Earth yardang,extraterrestrial yardang research has been carried out on Mars,Venus,and Titan.Recommendations and perspectives We then proposed that:(1)yardang formation ages,due to the erosion characteristics,are difficult to constraint;(2)the wind erosion capacity in the yardang areas might have been severely underestimated,making it essential to re-evaluate the previous paleoclimate reconstruction in the closed basins with limited chronological data;(3)yardang evolution is driven by climate change,but the coupling relationship between the yardang geomorphy and the air circulation is still unclear.Finally,future research directions:(1)more chronological data are needed,as well as the wind erosion capacity for yardang initiation and development;(2)the co-evolution of mid-low latitude landforms involved in yardang long-term variation and its relationship with global atmospheric circulation. 展开更多
关键词 yardang landform evolutionary model CHRONOLOGY wind erosion surface process
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说“恒代” 被引量:2
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作者 刘晓满 《许昌学院学报》 CAS 2008年第6期22-25,共4页
学术界只知道"恒代"是在孝文帝迁都洛阳后出现的,作为恒州代郡的省称,特指代都平城或其周围地区。殊不知在迁都洛阳之前已经出现"恒代",作为恒山代地的省称,泛指北魏国人拓跋族居住地区——"代地"。北魏... 学术界只知道"恒代"是在孝文帝迁都洛阳后出现的,作为恒州代郡的省称,特指代都平城或其周围地区。殊不知在迁都洛阳之前已经出现"恒代",作为恒山代地的省称,泛指北魏国人拓跋族居住地区——"代地"。北魏之"代地",即北魏拓跋猗卢代国代王"始封代土",与春秋战国及西汉初期的代王封地有相承关系。从区域概念上界定"恒代",就是北魏迁都洛阳之后的朔州黄河以东和恒州地区。恒代区域的东面是太行山脉,南面到恒山山脉和雁门山,西至黄河,北达阴山,可谓山河险要,易守难攻,具有独特的地理环境和民风社俗,不仅是拓跋魏的肇基之地,也是拓跋氏政权攻取中原的根据地,还是拓跋氏政权南下江淮的北方屏障,对北魏的政治变迁有着重要影响。 展开更多
关键词 北魏 恒代 恒州 代郡 代地 恒山
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“代马依北风”简析 被引量:1
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作者 袁延胜 《石家庄学院学报》 2017年第1期39-41,共3页
汉代"代马依北风"说法,对我们认识代地历史有很大的启示意义。首先,代马是产自代地的良马;其次,代马是北方之马,北方是代马的故乡;再次,随着秦汉时期代地的郡县化以及匈奴崛起的影响,"胡马"逐渐取代"代马"... 汉代"代马依北风"说法,对我们认识代地历史有很大的启示意义。首先,代马是产自代地的良马;其次,代马是北方之马,北方是代马的故乡;再次,随着秦汉时期代地的郡县化以及匈奴崛起的影响,"胡马"逐渐取代"代马"用来指代北方。 展开更多
关键词 代地 代马 胡马 汉代
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Geophysical data sparse reconstruction based on L0-norm minimization 被引量:6
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作者 陈国新 陈生昌 +1 位作者 王汉闯 张博 《Applied Geophysics》 SCIE CSCD 2013年第2期181-190,236,共11页
Missing data are a problem in geophysical surveys, and interpolation and reconstruction of missing data is part of the data processing and interpretation. Based on the sparseness of the geophysical data or the transfo... Missing data are a problem in geophysical surveys, and interpolation and reconstruction of missing data is part of the data processing and interpretation. Based on the sparseness of the geophysical data or the transform domain, we can improve the accuracy and stability of the reconstruction by transforming it to a sparse optimization problem. In this paper, we propose a mathematical model for the sparse reconstruction of data based on the LO-norm minimization. Furthermore, we discuss two types of the approximation algorithm for the LO- norm minimization according to the size and characteristics of the geophysical data: namely, the iteratively reweighted least-squares algorithm and the fast iterative hard thresholding algorithm. Theoretical and numerical analysis showed that applying the iteratively reweighted least-squares algorithm to the reconstruction of potential field data exploits its fast convergence rate, short calculation time, and high precision, whereas the fast iterative hard thresholding algorithm is more suitable for processing seismic data, moreover, its computational efficiency is better than that of the traditional iterative hard thresholding algorithm. 展开更多
关键词 Geophysical data sparse reconstruction LO-norm minimization iterativelyreweighted least squares fast iterative hard thresholding
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Research on Beautiful Countryside Planning in Underdeveloped Areas from Perspective of Traditional and Modern Integration——a Case Study of Jiangjia Village, Jishui County, Jiangxi Province 被引量:2
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作者 李小云 胡思琦 《Agricultural Science & Technology》 CAS 2016年第6期1468-1470,共3页
In context of building beautiful countryside nationwide, underdeveloped areas are confronted by many problems, such as monotonous industry structure, simi- lar rural landscape and loss of characteristics. With a case ... In context of building beautiful countryside nationwide, underdeveloped areas are confronted by many problems, such as monotonous industry structure, simi- lar rural landscape and loss of characteristics. With a case of Jiangjia Village, Jishui County, Jiangxi Province, the research explored rural pattern, cultural characteristics, building style, development value and potential and analyzed regional cooperation, urban-rural integration, and planning first, from the perspectives of economy, culture and building in order to protect traditional economy and highlight local characteristics. 展开更多
关键词 Tradition and modern INTEGRATION Underdeveloped areas Beautiful Countryside
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浅论山西代县的县名渊源
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作者 刘冬 《大观周刊》 2011年第21期40-40,24,共2页
春秋时狄族建立的古代国尽管存在时间较短、疆域较狭小,但在历史上,它对周边地区的发展有重大的影响。从最早的代郡、古代县,到代州,再到今天的山西代县,地名均受到了古代国的影响。今天的山西代县县名最早可追溯到古代国。
关键词 古代国 山西代县 代地 县名 渊源
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The Second-generation Wavelet Transform and its Application in Denoising of Seismic Data 被引量:19
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作者 曹思远 陈香朋 《Applied Geophysics》 SCIE CSCD 2005年第2期70-74,i0001,共6页
This paper discusses the principle and procedures of the second-generation wavelet transform and its application to the denoising of seismic data. Based on lifting steps, it is a flexible wavelet construction method u... This paper discusses the principle and procedures of the second-generation wavelet transform and its application to the denoising of seismic data. Based on lifting steps, it is a flexible wavelet construction method using linear and nonlinear spatial prediction and operators to implement the wavelet transform and to make it reversible. The lifting scheme transform -includes three steps: split, predict, and update. Deslauriers-Dubuc (4, 2) wavelet transforms are used to process both synthetic and real data in our second-generation wavelet transform. The processing results show that random noise is effectively suppressed and the signal to noise ratio improves remarkably. The lifting wavelet transform is an efficient algorithm. 展开更多
关键词 wavelet transform second-generation and denoise
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Several Fossil Woods from Mesozoic of Western Liaoning Province, Northeast, China 被引量:19
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作者 段淑英 《Acta Botanica Sinica》 CSCD 2000年第2期207-213,共7页
The author described some new species and genera of the fossil woods from Mesozoic of Western Liaoning besides Xenoxylon latiporosum (Cramer) Gothan, X. hopeiense Chang, X. liaoningense Duan et Wang, X. yixia... The author described some new species and genera of the fossil woods from Mesozoic of Western Liaoning besides Xenoxylon latiporosum (Cramer) Gothan, X. hopeiense Chang, X. liaoningense Duan et Wang, X. yixianense Zhang et Shang, Protopiceoxylon yizhouense Duan et Cui. They are Protopiceoxylon chaoyangense Duan sp. nov., Araucarioxylon batuense Duan sp. nov., Taxoxylon liaoxiense Duan sp. nov. and an old species Araucarioxylon sidugawaense Shimakura. 展开更多
关键词 Protopiceoxylon Araucarioxylon Taxoxylon
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The Gaoyuzhuang Palaeobiology 被引量:1
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作者 徐兆良 阿拉米克S.M. 《Acta Botanica Sinica》 CSCD 2002年第5期617-627,共11页
Black bedded, nodular, and lenticular chert and silicified parts of stromatolites from the approximately 1 400 - 1 600 million year-old Gaoyuzhuang Formation, North China, contain remark-ably well prep served microflo... Black bedded, nodular, and lenticular chert and silicified parts of stromatolites from the approximately 1 400 - 1 600 million year-old Gaoyuzhuang Formation, North China, contain remark-ably well prep served microflora composed of diverse prokaryotic and possible eukaryotic microbes. Macroscopic algae have also been found. This Formation provides important paleobiological information from which to assess status of Mesoproterozoic life, and to evaluate paleoenvironmental conditions and pre-Phanerozoic biostratigraphy. The Gaoyuzhuang Formation has yielded over 100 taxa described by over 10 investigators. Most of the microbial taxa can be divided into three different assemblages according to their paleobiological and paleoenvironmental characteristics. I. The oscillatoriacean/chroococcacean assemblage which occurs in the first member of the Formation and this is interpreted to represent an assemblage from shallow water mat-building and mat-dwelling taxa with some possible planktonic taxa; 2. the nostocacean assemblage found only in the second member, and includes benthic mat-building or mat-dwelling taxa; and 3. the chroococcacean assemblage of the fourth member, which represents intertidal to supratidal mat-building and allochthonous taxa. Proterozoic microfossils found in chert, especially cyanobacteria, are possibly more valuable as paleoenvironmental indicators than as chronostratigraphic tools because of their morphological conservation, although trends in diversity appear to exist for cyanobacteria in the Proterozoic. The general characteristics of Gaoyuzhuang microfossils, and the fact that most nostocacean chains occur and are. preserved with the chain perpendicular to bedding indicate that: (1) the individual size of Gaoyuzhuang microfossils are part of a general trend of increase with time; (2) Gaoyuzhuang deposits are possibly in a fresh water environment and the rate of sedimentation might be equal to or less than the microbial growth rate; (3) the sedimentary model of Gaoyuzhuang might be from intertidal to subtidal or deep sea, and then to intertidal or supratidal; and (4) the eukaryotic organisms had densely occurred when Gaoyuzhuang Formation deposited. 展开更多
关键词 North China MESOPROTEROZOIC Gaoyuzhuang Formation PALAEOBIOLOGY
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Complex seismic wavefi eld interpolation based on the Bregman iteration method in the sparse transform domain 被引量:2
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作者 勾福岩 刘财 +2 位作者 刘洋 冯晅 崔芳姿 《Applied Geophysics》 SCIE CSCD 2014年第3期277-288,350,351,共14页
In seismic prospecting, fi eld conditions and other factors hamper the recording of the complete seismic wavefi eld; thus, data interpolation is critical in seismic data processing. Especially, in complex conditions, ... In seismic prospecting, fi eld conditions and other factors hamper the recording of the complete seismic wavefi eld; thus, data interpolation is critical in seismic data processing. Especially, in complex conditions, prestack missing data affect the subsequent highprecision data processing workfl ow. Compressive sensing is an effective strategy for seismic data interpolation by optimally representing the complex seismic wavefi eld and using fast and accurate iterative algorithms. The seislet transform is a sparse multiscale transform well suited for representing the seismic wavefield, as it can effectively compress seismic events. Furthermore, the Bregman iterative algorithm is an efficient algorithm for sparse representation in compressive sensing. Seismic data interpolation methods can be developed by combining seismic dynamic prediction, image transform, and compressive sensing. In this study, we link seismic data interpolation and constrained optimization. We selected the OC-seislet sparse transform to represent complex wavefields and used the Bregman iteration method to solve the hybrid norm inverse problem under the compressed sensing framework. In addition, we used an H-curve method to choose the threshold parameter in the Bregman iteration method. Thus, we achieved fast and accurate reconstruction of the seismic wavefi eld. Model and fi eld data tests demonstrate that the Bregman iteration method based on the H-curve norm in the sparse transform domain can effectively reconstruct missing complex wavefi eld data. 展开更多
关键词 Bregman iteration OC-seislet transform seismic data interpolation compressive sensing H-curve norm
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Metabolism of Praziquantel in Erythromycin, Acetylspi-ramycin and Dexamethasone Induced Rat Liver Micro-somes
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作者 赵梁立 黄婉芸 全钰珠 《Journal of Chinese Pharmaceutical Sciences》 CAS 1995年第2期75-81,共7页
Our results show that in liver microsomes from erythromycin,acetylspiramycin and dexamethsone pretreated rats,the rate of praziquantel( PQT)disappearence was increased as compared with control rat When microsomes fro... Our results show that in liver microsomes from erythromycin,acetylspiramycin and dexamethsone pretreated rats,the rate of praziquantel( PQT)disappearence was increased as compared with control rat When microsomes from erythromycin-treated rats were exposed to PQT in the presence of potassium ferricyanide which broke down the cytochrome P-450 Fe(Ⅱ)-metabolite complexes and restored the functional cytochrome P-450,PQT metabolism was further increased. Acetylspiramycin did not form the complexes, so potassium ferricyanide showed no effect on the PQT metabolism in microsomes from acetylspiramycin-treated rats. Triacetyloleandomycin,a specific inhibitor of cytochrome P-450ⅢAI, inhibited PQT metabolism by 53% in liver microsomes from dexamethasone-treated rats.These results indicate the cytochrome P-450ⅢA seems to be involved in metabolism of PQT in rat liver microsomes. 展开更多
关键词 Praziquantel Liver microsomes DEXAMETHASONE ERYTHROMYCIN Cytochrome P-450:Rat
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Serum Bcl-2 concentrations in overweight-obese subjects with nonalcoholic fatty liver disease 被引量:11
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作者 Giovanni Tarantino Francesco Scopacasa +4 位作者 Annamaria Colao Domenico Capone Marianna Tarantino Ernesto Grimaldi Silvia Savastano 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第48期5280-5288,共9页
AIM: To shed some light on the relationship between anti-apoptotic serum Bcl-2 concentrations and metabolic status, anthropometric parameters, inflammation indi- ces, and non-alcoholic fatty liver disease severity we... AIM: To shed some light on the relationship between anti-apoptotic serum Bcl-2 concentrations and metabolic status, anthropometric parameters, inflammation indi- ces, and non-alcoholic fatty liver disease severity were investigated in 43 young individuals with fatty liver (FL) and 41 with nonalcoholic steatohepatitis (NASH). METHODS: Circulating levels of Bcl-2 were detected in 84 patients with ultrasonographic findings of "bright liver" and/or hyper-transaminasemia of unknown origin and/or increase in T-glutamyl-transpeptidase (T-GT) strictly in the absence of other acute or chronic liver disease, whose age was not advanced, who gave consent to liver biopsy and were then divided on the basis of the histological results into two groups (43 with FL and 41 with NASH). Twenty lean subjects, apparently healthy and young, were chosen as controls.RESULTS: Serum Bcl-2 concentrations were significantly higher in the FL group than in the NASH group. Insulin resistance and γ-GT activity were significantly higher in NASH subjects. Apoptotic hepatocytes were significantly more numerous in NASH patients. NASH patients presented with larger spleens and augmented C-reactive protein (CRP) concentrations than healthy subjects. Steatosis grade at histology was similar in both NASH and FL populations. The number of apoptotic cells was significantly related to anti-apoptotic Bcl-2 protein values in FL patients. Bcl-2 serum levels positively correlated to body mass index (BMI) values (P ~ 0.0001) but not to age of the population. Triglycerides/HDL ratio correlated well to waist circumference in males (P = 0.0008). γ-GT activity was associated with homeostatic metabolic assessment (HOMA) (P = 0.0003) and with serum ferritin (P = 0.02). Bcl-2 concentrations were not related to either spleen size or CRP values. NASH patients pre- sented a weak negative correlation between Iobular inflammation and Bcl-2 levels. A prediction by low values of serum Bcl-2 towards a greater presence of metabolically unhealthy overweight/obese patients (MUOs) was evidenced. HOMA, BMI and uric acid, in that sequence, best predicted serum Bcl-2 concentrations. CONCLUSION: IvlUOs could be detected by Bcl-2 levels. By favoring the life span of hepatocytes, and enhancing triglyceride formation, the anti-apoptotic process inhibits free fatty acids toxicity in FL. 展开更多
关键词 BCL-2 Nonalcoholic fatty liver disease Meta-bolically unhealthy overweight/obese
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On the Tectonic Problems of the Southern East China Sea and Adjacent Regions:Evidence from Gravity and Magnetic Data 被引量:2
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作者 SHANG Luning ZHANG Xunhua +1 位作者 HAN Bo DU Runlin 《Journal of Ocean University of China》 SCIE CAS 2016年第1期93-106,共14页
In this paper, two sets of gravity and magnetic data were used to study the tectonics of the southern East China Sea and Ryukyu trench-arc system: one data set was from the 'Geological-geophysical map series of Chin... In this paper, two sets of gravity and magnetic data were used to study the tectonics of the southern East China Sea and Ryukyu trench-arc system: one data set was from the 'Geological-geophysical map series of China Seas and adjacent areas' database and the other was newly collected by R/VKexue Ⅲ in 2011. Magnetic and gravity data were reorganized and processed using the software MMDP, MGDP and RGIS. In addition to the description of the anomaly patterns in different areas, deep and shallow structure studies were performed by using several kinds of calculation, including a spectrum analysis, upward-continuation of the Bouguer anomaly and horizontal derivatives of the total-field magnetic anomaly. The depth of the Moho and magnetic basement were calculated. Based on the above work, several controversial tectonic problems were discussed. Compared to the shelf area and Ryukyu Arc, the Okinawa Trough has an obviously thinned crust, with the thinnest area having thickness less than 14km in the southern part. The Taiwan-Sinzi belt, which terminates to the south by the NW-SE trending Miyako fault belt, contains the relic volcanic arc formed by the splitting of the paleo Ryukyu volcanic arc as a result of the opening of the Okinawa Trough. As an important tectonic boundary, the strike-slip type Miyako fault belt extends northwestward into the shelf area and consists of several discontinuous segments. A forearc terrace composed of an exotic terrane collided with the Ryukyu Arc following the subduction of the Philippine Sea Plate. Mesozoic strata of varying thicknesses exist beneath the Cenozoic strata in the shelf basin and significantly influence the magnetic pattern of this area. The gravity and magnetic data support the existence of a Great East China Sea, which suggests that the entire southern East China Sea shelf area was a basin in the Mesozoic without alternatively arranged uplifts and depressions, and might have extended southwestward and connected with the northern South China Sea shelf basin. 展开更多
关键词 TECTONICS southern East China Sea Ryukyu trench-arc system gravity anomaly magnetic anomaly
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Neoproterozoic stratigraphic correlation of Subei-Huainan in China 被引量:1
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作者 刘为付 刘双龙 +3 位作者 孙立新 白文爽 丁振坤 王泽宇 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第6期1449-1458,共10页
Subei-Huainan in the southeastern margin of the North China platform is a key area of convergence of China’s north-south stratigraphic correlation of Neoproterozoic.Due to the lack of fossils,the Neoproterozoic strat... Subei-Huainan in the southeastern margin of the North China platform is a key area of convergence of China’s north-south stratigraphic correlation of Neoproterozoic.Due to the lack of fossils,the Neoproterozoic stratigraphic correlation is still a difficulty in this area.The division of Neoproterozoic strata and the establishment of the correlation framework of the stratigraphic sequences have been done through recognizing the regularity of meter-scale cycles by measuring the outcrop of Neoproterozoic strata and using the Fischer diagram and the sea-level curve of transgressive-regressive by the maximum flooding sedimentary and molar teeth carbonate sedimentary.The maximum flooding sedimentary which becomes cycle sequence comparison of sign is isochronous in the same basin and is a key of cycle sequence comparison although paleogeographic environment and sedimentary sequence may be different in the sedimentary strata of the same geologic time.Molars carbonates,having specific geological distrution time and depositional environment and mainly developing in the ramp environment of the platform edge in the 1500-650 Ma,are the new symbol of the stratigraphic correlation in the Neoproterozoic.Because of the missing of the fossil record,the maximum flooding and the molar-teeth carbonate sedimentary,as the new research ideas,are used in stratigraphic division and correlation. 展开更多
关键词 Fischer diagram sea-level change molar-teeth carbonate maximum flooding sedimentary NEOPROTEROZOIC Subei-Huainan
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NLoS Mitigation in ToA Localization Based on Spatial Correlation Filter and Iterative Minimum Residual 被引量:3
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作者 Luo Haiyong Liu Shujing Liu Xiaoming 《China Communications》 SCIE CSCD 2012年第4期13-19,共7页
To mitigate the Non-Line-of-Sight (NLoS) error which seriously affects the localization accuracy and robustness in complex indoor environment,a novel Iterative Minimum Residual (IMR) based on the consistency hypothesi... To mitigate the Non-Line-of-Sight (NLoS) error which seriously affects the localization accuracy and robustness in complex indoor environment,a novel Iterative Minimum Residual (IMR) based on the consistency hypothesis of the residual and the error is proposed in this paper.It chooses the best subset of measurements to calculate the coordinates of the unknown node by comparing the residuals obtained with different subsets of beacons.To reduce the time complexity of the IMR algorithm,Spatial Correlation Filter (SCF) is also proposed,which can remove the most serious NLoS distance with low calculation cost.Combined with the proposed SCF and IMR algorithm,nodes can be localized with high accuracy and low time complexity.Experimental results with real dataset demonstrate that the proposed algorithm can identify the NLoS range effectively with about 50% time cost of employing SCF only. 展开更多
关键词 LOCALIZATION NLoS mitigation TOA iterativeminimum residual spatial correlation filter
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The extreme dry/wet events in northern China during recent 100 years 被引量:10
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作者 马柱国 丹利 胡跃文 《Journal of Geographical Sciences》 SCIE CSCD 2004年第3期275-281,共7页
Using monthly precipitation and monthly mean temperature, a surface humid index was proposed. According to the index, the distributed characteristics of extreme dryness has been fully analyzed. The results indicated t... Using monthly precipitation and monthly mean temperature, a surface humid index was proposed. According to the index, the distributed characteristics of extreme dryness has been fully analyzed. The results indicated that there is an obvious increasing trend of extreme dryness in the central part of northern China and northeastern China in the last 10 years, which shows a high frequency period of extreme dryness; while a low frequency period in the regions during the last 100 years. Compared with variation trend of the temperature in these regions, the region of high frequent extreme dryness is consistent with the warming trend in the same region. 展开更多
关键词 monthly precipitation air temperature surface humid index CLIMATE extremedryness
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Structural Characteristics of Paleozoic and Geological Significance of Oil and Gas of Dongpu Depression 被引量:2
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作者 杨世刚 《Journal of China University of Mining and Technology》 2003年第1期97-102,共6页
The Dongpu depression has experienced a complicated evolution of structure since Mesozoic. The Paleozoic carbonate rock has been strongly reformed and the buried hills with different characteristics of structure are d... The Dongpu depression has experienced a complicated evolution of structure since Mesozoic. The Paleozoic carbonate rock has been strongly reformed and the buried hills with different characteristics of structure are developed in the depression. There exist lots of groups of fault structures with strikes of NNE(or NE),NW, near NS and EW etc., of which the faults with strikes of NNE and NW play an important controlling role on present-day structural framework of the depression. The faults with near NS-striking and EW-striking deeply affect the establishment of structural framework of basement of the depression. Although most of the fractures are filled by calcite and other minerals, under the action of later structural stress, the earlier fractures could change their features into tensional ones. Therefore, much attention should be paid to the exploration and exploitation of Paleozoic oil and gas in Dongpu depression. 展开更多
关键词 Dongpu depression PALEOZOIC STRUCTURE oil-gas geology
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Fenlong Cultivation-the Fourth Set of Farming Methods Invented in China 被引量:17
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作者 韦本辉 《Agricultural Science & Technology》 CAS 2017年第11期2045-2048,2052,共5页
The basic theory and effect of the new farming method of "Fenlong" cultivation which has been included in the main extension technology of Ministry of Agriculture of the People's Republic of China is fully illustra... The basic theory and effect of the new farming method of "Fenlong" cultivation which has been included in the main extension technology of Ministry of Agriculture of the People's Republic of China is fully illustrated for the first time, and it is the fourth set (generation) of farming modes and methods following manpower, animal and mechanical (tractor) farming. It follows the natural law to achieve soil activation, water saving, oxygen increase, warming and desalination through the active use of natural resources like soil, rainfall and solar energy, thereby promoting a new round of natural agricultural production and quality improvement and water con- servation, which has crop yield increase by 10%-30%, quality improvement of 5%, natural precipitation retaining increase by100%. The characteristics and mechanism are the use of spiral drill for one-time completion of the land preparation by drilling vertically to 30-50 cm of soil layer through high speed peeling. After instant high temperature and many fierce impacts, mechanical frictions, it could achieve the multiplication of the number of loose soil, soil physical modification and expansion of the soil nutrients, reservoirs, oxygen, microorganisms ("Four pools"). Fenlong cultivation can give birth to new farming culture and civilization, and it can achieve the physical "desalinized" transformation and utilization of saline soil. The formation of Fenlong green farming technology system makes it possible to invent the farming tools of "serf-propelled Fenlong machinery" that has got the patent, and it is the method for farmland (dry land, paddy field) Fenlong cultivation, saline-alkali soil smash-ridging cultivation and for the abundance of grass ecology on degraded grassland. The application of Fenlong "4+1" (arable, saline-alkali soil, grasslands, Sponge City+rivers) green development in China can achieve the "double safety" of food and living space. 展开更多
关键词 Fenlong cultivation The fourth set (generation) of new farming methods Activation and utilization of natural resources Improvement of production and quality Water conservation ecology
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