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The Ups and Downs ofModern Dance in China
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《China & The World Cultural Exchange》 1997年第3期30-32,共3页
关键词 the ups and downs ofModern Dance in China In
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对“The Land of the Lock”的设计
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作者 秦德娟 王仕宗 马宁 《牡丹江教育学院学报》 2010年第4期147-148,共2页
英语课堂上“以教师为中心”的现象处处可见,为改变这一局面,本文对《大学英语》第三册第三课“The Land of the Lock”进行了设计。该设计主要以“top—down”阅读策略为主,用以提升学生把握篇章内容的能力和猜词能力,力争做到“... 英语课堂上“以教师为中心”的现象处处可见,为改变这一局面,本文对《大学英语》第三册第三课“The Land of the Lock”进行了设计。该设计主要以“top—down”阅读策略为主,用以提升学生把握篇章内容的能力和猜词能力,力争做到“以学生为中心”。 展开更多
关键词 STUDENT-CENTERED TOP-DOWN BOTTOM-UP
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Early warning signals of abrupt temperature change in different regions of China over the past 50 years 被引量:2
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作者 仝纪龙 吴浩 +2 位作者 侯威 何文平 周杰 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第4期723-731,共9页
In this paper, the early warning signals of abrupt temperature change in different regions of China are investigated. Seven regions are divided on the basis of different climate temperature patterns, obtained through ... In this paper, the early warning signals of abrupt temperature change in different regions of China are investigated. Seven regions are divided on the basis of different climate temperature patterns, obtained through the rotated empirical orthogonal function, and the signal-to-noise temperature ratios for each region are then calculated. Based on the concept of critical slowing down, the temperature data that contain noise in the different regions of China are preprocessed to study the early warning signals of abrupt climate change. First, the Mann-Kendall method is used to identify the instant of abrupt climate change in the temperature data. Second, autocorrelation coefficients that can identify critical slowing down are calculated. The results show that the critical slowing down phenomenon appeared in temperature data about 5-10 years before abrupt climate change occurred, which indicates that the critical slowing down phenomenon is a possible early warning signal for abrupt climate change, and that noise has less influence on the detection results of the early warning signals. Accordingly, this demonstrates that the model is reliable in identifying the early warning signals of abrupt climate change based on detecting the critical slowing down phenomenon, which provides an experimental basis for the actual application of the method. 展开更多
关键词 abrupt climate change critical slowing down rotated empirical orthogonal function early warning signal
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A study of the early warning signals of abrupt change in the Pacific decadal oscillation 被引量:1
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作者 吴浩 侯威 +2 位作者 颜鹏程 张志森 王阔 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第8期662-673,共12页
In recent years, the phenomenon of a critical slowing down has demonstrated its major potential in discovering whether a complex dynamic system tends to abruptly change at critical points. This research on the Pacific... In recent years, the phenomenon of a critical slowing down has demonstrated its major potential in discovering whether a complex dynamic system tends to abruptly change at critical points. This research on the Pacific decadal oscillation(PDO) index has been made on the basis of the critical slowing down principle in order to analyze its early warning signal of abrupt change. The chaotic characteristics of the PDO index sequence at different times are determined by using the largest Lyapunov exponent(LLE). The relationship between the regional sea surface temperature(SST) background field and the early warning signal of the PDO abrupt change is further studied through calculating the variance of the SST in the PDO region and the spatial distribution of the autocorrelation coefficient, thereby providing the experimental foundation for the extensive application of the method of the critical slowing down phenomenon. Our results show that the phenomenon of critical slowing down, such as the increase of the variance and autocorrelation coefficient, will continue for six years before the abrupt change of the PDO index. This phenomenon of the critical slowing down can be regarded as one of the early warning signals of an abrupt change. Through calculating the LLE of the PDO index during different times, it is also found that the strongest chaotic characteristics of the system occurred between 1971 and 1975 in the early stages of an abrupt change(1976), and the system was at the stage of a critical slowing down, which proves the reliability of the early warning signal of abrupt change discovered in 1970 from the mechanism. In addition, the variance of the SST,along with the spatial distribution of the autocorrelation coefficient in the corresponding PDO region, also demonstrates the corresponding relationship between the change of the background field of the SST and the change of the PDO. 展开更多
关键词 abrupt climate change critical slowing down early warning signals largest Lyapunov exponent sea surface temperature
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Impact of LUCC on Ecosystem Service Value in the Up and Middle Reaches of Dongting Lake Basin,China 被引量:1
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作者 XIONG Ying WANG Kelin LIU Chun 《湿地科学》 CSCD 2009年第4期327-334,共8页
Supported by geographical information system,using Costanza method and referring to terrestrial ecosystem service value in China,the influence of land use and land cover change(LUCC)between 1980 and 2000 on ecosystem ... Supported by geographical information system,using Costanza method and referring to terrestrial ecosystem service value in China,the influence of land use and land cover change(LUCC)between 1980 and 2000 on ecosystem service value in the up and middle reaches of Dongting Lake basin was analyzed in this study.The results showed that the estimated value of ecosystem services decreased 8.416 9×108 CNY over a 21-year period,and the main reasons were that the land for forest use was exploited for cropland and construction land use in study area.Further analysis results showed that the value of single ecosystem service function such as gas regulation,climate regulation,soil formation and conservation,biodiversity conservation,raw materials as well as recreation decreased significantly;and that of provision of water conservation,waste treatment and food production increased obviously in the area.The results of coefficient sensitivity analysis indicated that these estimates were reliable. 展开更多
关键词 生态学 LUCC 湿地 地貌学
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Ups and Downs for China's Securities Dealers
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《China's Foreign Trade》 1999年第10期4-7,共4页
关键词 ups and downs for China’s Securities Dealers In
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THE DYNAMICS OF MAINTAINING THE TROPICAL CYCLONE 9012 AFTER ITS LANDING
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作者 梁力 吴志伟 严光华 《Journal of Tropical Meteorology》 SCIE 1996年第1期35-45,共11页
Using 2. 5 ×2. 5 winds and pressure grid data, the angular momentum budgets are studied in this paper for TC 9012 (Yancy) which was kept active 65 hours after land fall. It is found that the inland TC 9012 moved ... Using 2. 5 ×2. 5 winds and pressure grid data, the angular momentum budgets are studied in this paper for TC 9012 (Yancy) which was kept active 65 hours after land fall. It is found that the inland TC 9012 moved into the center of a relatively stable saddle, in which large amount of humid air was entrained into the storm from the southerly jet at low level to bund up the energy of latent heat, the weak cold air coming from the north provided it with baroclinic energy, while the vorticity transfer of geostrophic angular momentum on the radius 4°-8°from the cyclone center at upper troposphere and the input of cyclonic angular momentum produced by the βterm are immediate factors maintaining the central pressure and maximum winds. 展开更多
关键词 long maintenance ANGULAR MOMENTUM transport SPIN-UP or SPIN-DOWN
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Blown Film Extrusion Process for Polybags: Technical Overview and Applications
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作者 Sunil Badgujar Sudeep Asthana +6 位作者 Ravindra Kanawade Krunal Suthar Ankit Solanki Karuppiah Nagaraj Mahaveer Singh Bilkhu Harekrushna Sutar Swapna Rekha Panda 《Advances in Chemical Engineering and Science》 CAS 2024年第4期188-201,共14页
The choice of extrusion process is a decisive factor that affects the finished product quality for polybag manufacturing. One important component influencing the quality of the finished product is the selection of the... The choice of extrusion process is a decisive factor that affects the finished product quality for polybag manufacturing. One important component influencing the quality of the finished product is the selection of the extrusion technique. Two popular procedures that vary in the kind of dye used and the final product’s texture are cast film and blown film. In the horizontal extrusion moulding method known as “cast film”, heated resin is injected into a flat dye and allowed to cool on chill rolls. The film produced is clear, lightweight, and appropriate for lamination;its thickness varies based on the winding speed and the film is slower to crystallize and has less clarity but more durability because the resin molecules have reoriented, facing limitation of high wastage generation. This study primarily focused on the preparation of polybag film using the blown film extrusion process, utilizing high-quality polymer resins such as polyester polyethylene (PP) and linear low-density polyethylene (LLDPE) to minimize waste generation. The novelty of the process was reflected in minimising the waste generation. The control parameters considered in this study are temperature, pressure, and air intake volume. We investigated the influence of these critical process control parameters on the gauge thickness, optical properties, and mechanical strength of the polybag film produced through blown film extrusion. Additionally, we replicated the blown film process using simulation software developed at Pennsylvania College of Technology. The simulation results confirmed the overall stability of the polybag film produced through the blown film extrusion process. 展开更多
关键词 LLDPE Melt Flow Index Blow-Up Ratio Lay-Flat Width Draw-Down Ratio
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Population Dynamics of Large Herbivores and the Framing of Wildlife Conservation in Zimbabwe
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作者 Edson Gandiwa 《Open Journal of Ecology》 2014年第7期411-420,共10页
This article reviews: 1) The role of natural and human-induced controls in influencing large herbivore populations;2) how human controls (i.e., policy instruments, incentives and provisions) influence human activities... This article reviews: 1) The role of natural and human-induced controls in influencing large herbivore populations;2) how human controls (i.e., policy instruments, incentives and provisions) influence human activities and wildlife conservation;and 3) media framing of wildlife conservation using Zimbabwe as a case study, in particular Gonarezhou National Park and adjacent areas. The review shows that droughts are important in influencing large herbivore populations in semi-arid ecosystems;political instability and economic collapse does not necessarily lead to increased illegal hunting in situations where policy instruments, such as laws, are enforced. A higher perceived effectiveness of Communal Areas Management Programme for Indigenous Resources was partly associated with a decline in human-wildlife conflicts and there was a spill-over effect of frames from the political domain into wildlife conservation following Zimbabwe’s land reforms in 2000. It is concluded that natural bottom-up processes (e.g., droughts) influence large herbivore population dynamics whereas policy instruments, incentives, provisions and societal frames mainly have a top-down effect on wild large herbivore populations in savanna ecosystems. 展开更多
关键词 BOTTOM-UP CONTROL ILLEGAL HUNTING Law ENFORCEMENT Media FRAMING Top-Down CONTROL
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Standard Model Fermion Masses and Charges from Holographic Analysis
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作者 T. R. Mongan 《Journal of Modern Physics》 2024年第6期796-803,共8页
The Standard Model of particle physics involves twelve fundamental fermions, treated as point particles, in four charge states. However, the Standard Model does not explain why only three fermions are in each charge s... The Standard Model of particle physics involves twelve fundamental fermions, treated as point particles, in four charge states. However, the Standard Model does not explain why only three fermions are in each charge state or account for neutrino mass. This holographic analysis treats charged Standard Model fermions as spheres with mass 0.187 g/cm<sup>2</sup> times their surface area, using the proportionality constant in the holographic relation between mass of the observable universe and event horizon radius. The analysis requires three Standard Model fermions per charge state and relates up quark and down quark masses to electron mass. Holographic analysis specifies electron mass, to six significant figures, in terms of fundamental constants α,ℏ,G,Λ and Ω Λ . Treating neutrinos as spheres and equating electron neutrino energy density with cosmic vacuum energy density predicts neutrino masses consistent with experiment. 展开更多
关键词 Electron Mass Up Quark Mass Down Quark Mass Neutrino Masses
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Application of the Bottom-up Method on Risk Evaluation of Climate Change in Water Resources System
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作者 李科 齐晶瑶 +1 位作者 BROWN Casey 王灵芝 《Journal of Donghua University(English Edition)》 EI CAS 2015年第5期851-854,共4页
Traditional approach to evaluate the impacts of climate change on the water resources systems always begins with downscaling general circulation models( GCMs) and proceeding back to the hydrological model. This approa... Traditional approach to evaluate the impacts of climate change on the water resources systems always begins with downscaling general circulation models( GCMs) and proceeding back to the hydrological model. This approach has some distinct disadvantages: 1) GCM must be downscaled; 2) different GCMs are difficult to be reconciled for a given climate change scenario;3) the uncertainty of GCMs is far from the requirement of the evaluation of climate change impacts. To overcome these limits of the traditional method,a new method termed as "bottom-up"was used for climate risk assessment that linked vulnerability assessment with climate information to assess the risk of climate change impacts on the Quabbin Reservoir,and United States under A2 scenario.The result shows that the risks are around 20% in 2006-2035 and 2036-2055,50% in 2066-2095. 展开更多
关键词 climate change water resources systems general circulation models(GCMs) RISK bottom-up method
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Demon Genes May Deform Common Syndromes: Collagen VI Gene Change in Down Syndrome Unifies the Medical and Molecular Approach to Hypermobility Disorders
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作者 Golder N. Wilson Vijay S. Tonk 《Journal of Biosciences and Medicines》 2022年第3期1-7,共7页
Purpose: To alert the medical community that whole exome sequencing can find accessory gene changes in well-known syndromes that alter preventive health care and management. Meaning: A collagen type VI gene change add... Purpose: To alert the medical community that whole exome sequencing can find accessory gene changes in well-known syndromes that alter preventive health care and management. Meaning: A collagen type VI gene change adds muscle weakness, hypermobility, and dysautonomia concerns to usual management considerations for Down syndrome. Methods: Commercial whole exome sequencing combined with clinical interpretation of DNA sequence change added new considerations to patient management and parental counsel. Results: An 11-year-old child with the trisomy 21 form of Down syndrome who was evaluated for extraordinary joint laxity had a heterozygous collagen type VI aspartic to glutamic acid (COL6A3 c.6360 C>G p.Asp2120Glu) gene change found by whole exome sequencing. The DNA variant was qualified as having strong relevance to the enhanced hypermobility due to prior association of collagen 6 gene changes with myopathy. Conclusions: Dual diagnosis of Ehlers-Danlos syndrome was not assigned because the patient lacked criteria like bruising, unusual scars, or selected dysautonomia symptoms. The concept of a hypermobility spectrum offers advantages for management of its constituent conditions if clinically guided ascertainment and DNA diagnostics are employed. 展开更多
关键词 Hypermobility Spectrum Disorders Down Syndrome Ehlers-Danlos Syndrome DNA Variant Qualification Collagen Type VI DNA change
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Theories of Reading and the Teaching of English Reading
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作者 陈春梅 《海外英语》 2012年第1X期112-114,120,共4页
English reading has gained much attention among teachers and students and become one of the research heatpots in English pedagogy.The paper gives a brief introduction of the theories of reading and attempts to apply t... English reading has gained much attention among teachers and students and become one of the research heatpots in English pedagogy.The paper gives a brief introduction of the theories of reading and attempts to apply the schema theory of reading into the classroom teaching.The classroom practice reveals that English reading under the guidance of schema theory proves effective and raises students' awareness of strategies. 展开更多
关键词 the "bottom-up" VIEW the "top-down" VIEW the "inte
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Sensitivity Test and Data Analysis for Storage Reliability Assessment of Explosive Initiator 被引量:2
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作者 洪东跑 赵宇 《Defence Technology(防务技术)》 SCIE EI CAS 2010年第2期119-125,共7页
The explosive initiator is one kind of sensitivity products with long life and high reliability.In order to improve the storage reliability assessment,the method of storage reliability assessment for explosive initiat... The explosive initiator is one kind of sensitivity products with long life and high reliability.In order to improve the storage reliability assessment,the method of storage reliability assessment for explosive initiator was proposed based on time series model using the sensitivity test data.In the method,the up and down test was used to estimate the distribution parameters of threshold.And an approach to design the up and down test was present to draw better estimations.Furthermore,the method of shrinkage estimation was introduced to get a better estimation of scale parameter by combining the sample information with prior information.The simulation result shows that the shrinkage estimation is better than traditional estimation under certain conditions.With the distribution parameters estimations,the time series models were used to describe the changing trends of distribution parameters along with storage time.Then for a fixed storage time,the distribution parameters were predicted based on the models.Finally,the confidence interval of storage reliability was obtained by fiducial inference.The illustrative example shows that the method is available for storage reliability assessment of the explosive initiator with high reliability. 展开更多
关键词 system engineering storage reliability explosive initiator up and down test time series model shrinkage estimation
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Dynamics of Urbanization and Its Impact on Land-Use/Land-Cover: A Case Study of Megacity Delhi 被引量:11
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作者 Manju Mohan Subhan K. Pathan +2 位作者 Kolli Narendrareddy Anurag Kandya Sucheta Pandey 《Journal of Environmental Protection》 2011年第9期1274-1283,共10页
The rapid expansion of urban areas due to rise in population and economic growth is increasing additional demand on natural resources thereby causing land-use changes especially in megacities. Therefore, serious probl... The rapid expansion of urban areas due to rise in population and economic growth is increasing additional demand on natural resources thereby causing land-use changes especially in megacities. Therefore, serious problems associated with rapid development such as additional infrastructure, informal settlements, environmental pollution, destruction of ecological structure and scarcity of natural resources has been studied carefully using remote sensing and GIS technologies for a rapidly grown megacity namely, Delhi. The present work evaluates the land use/land cover (LULC) changes and urban expansion in Mega city Delhi and highlights the major impact of rapid urbanization and population growth on the land cover changes which needs immediate attention. The results indicate that the city is expanding towards its peripheral region with the conversion of rural regions in to urban expansions. Built-up area of Delhi witnessed an overall increment from 540.7 km2 to 791.96 km2 or 16.86% of the total city area (1,490 km2 ) during the study period 1997 to 2008 which mainly came from agriculture land, waste land, scrub-land, sandy areas and water bodies. The increment in forest cover of 0.5 % is very small when considering the increment in built up category to 17%. Total area of waterbodies has reduced by 52.9% in a ten year period (58.26 km2 in 1997 to 27.43 km2 in 2008) with shallow waterbodies now having a dismal presence. LULC changes are studied with the urban growth parameters such as population, vehicles, gross state domestic product etc. The results lay emphasis on the concepts of urban planning to be applied such that more consideration is towards the preservation and management of natural land use classes which will increase the quality of life in an urban environment. 展开更多
关键词 Satellite Imagery Landuse-Landcover Distribution URBAN Planning BUILT-UP Areas URBAN Growth Parameters change Detection
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Pharmacological- and non-pharmacological therapeutic approaches in inflammatory bowel disease in adults 被引量:4
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作者 Gerda C Leitner Harald Vogelsang 《World Journal of Gastrointestinal Pharmacology and Therapeutics》 CAS 2016年第1期5-20,共16页
Inflammatory bowel diseases (IBDs) are a group of chronic inflammatory conditions mainly of the colon and small intestine. Crohn&rsquo;s disease (CD) and ulcerative colitis (UC) are the most frequent types of IBD.... Inflammatory bowel diseases (IBDs) are a group of chronic inflammatory conditions mainly of the colon and small intestine. Crohn&rsquo;s disease (CD) and ulcerative colitis (UC) are the most frequent types of IBD. IBD is a complex disease which arises as a result of the interaction of environmental, genetic and immunological factors. It is increasingly thought that alterations of immunological reactions of the patients to their own enterable bacteria (microfilm) may contribute to inflammation. It is characterized by mucosal and sub mucosal inflammation, perpetuated by infiltration of activated leukocytes. CD may affect the whole gastrointestinal tract while UC only attacks the large intestine. The therapeutic goal is to achieve a steroid-free long lasting remission in both entities. UC has the possibility to be cured by a total colectomy, while CD never can be cured by any operation. A lifelong intake of drugs is mostly necessary and essential. Medical treatment of IBD has to be individualized to each patient and usually starts with anti-inflammatory drugs. The choice what kind of drugs and what route administered (oral, rectal, intravenous) depends on factors including the type, the localization, and severity of the patient&rsquo;s disease. IBD may require immune-suppression to control symptoms such as prednisolone, thiopurines, calcineurin or sometimes folic acid inhibitors or biologics like TNF-&alpha; inhibitors or anti-integrin antibodies. For both types of disease (CD, UC) the same drugs are available but they differ in their preference in efficacy between CD and UC as 5-aminosalicylic acid for UC or budesonide for ileocecal CD. As therapeutic alternative the main mediators of the disease, namely the activated pro-inflammatory cytokine producing leukocytes can be selectively removed via two apheresis systems (Adacolumn and Cellsorba) in steroid-refractory or dependent cases. Extracorporeal photopheresis results in an increase of regulatory B cells, regulatory CD8<sup>+</sup> T cells and T-regs Type 1. Both types of apheresis were able to induce clinical remission and mucosal healing accompanied by tapering of steroids. 展开更多
关键词 Inflammatory bowel disease Crohn&rsquo s disease Ulcerative colitis Extracorporeal treatment Step up/top down Psychological aspects in inflammatory bowel disease Current medical treatment of inflammatory bowel disease Future therapeutical strategies
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The Application of The Top-down Approach in Teaching Extensive Reading
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作者 陈国静 《海外英语》 2011年第5X期36-37,39,共3页
The top-down and bottom-up are two main approaches used in teaching extensive reading and both of them should be used alternatively so that students can not only understand the details but also the main ideas of readi... The top-down and bottom-up are two main approaches used in teaching extensive reading and both of them should be used alternatively so that students can not only understand the details but also the main ideas of reading materials.The importance of using top-down approach is emphasized and some suggestions are given on the problem that students pay so much attention on vocabulary and grammar rather than main idea in reading. 展开更多
关键词 READING TOP-DOWN BOTTOM-UP
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A Cognitive Comparative Analysis of UP-DOWN Metaphorical Extension in Chinese and English
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作者 张长永 《科技信息》 2011年第20期177-179,共3页
This paper aims at making some research on spatial metaphor from cognitive angle.Spatial metaphor is a basic tool which can make us more familiar with our world,and lots of abstract concepts are based on it.Take "... This paper aims at making some research on spatial metaphor from cognitive angle.Spatial metaphor is a basic tool which can make us more familiar with our world,and lots of abstract concepts are based on it.Take "UP-DOWN" for example,this paper will mainly discuss the symmetry and dissymmetry of its extension in Chinese and English. 展开更多
关键词 英文文摘 内容介绍 期刊 《科技信息》
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GENERALIZED FATIGUE CONSTANT LIFE CURVE AND TWO-DIMENSIONAL PROBABILITY DISTRIBUTION OF FATIGUE LIMIT
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作者 熊峻江 武哲 高镇同 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第10期1188-1193,共6页
According to the traditional fatigue constant life curve, the concept and the universal expression of the generalized fatigue constant life curve were proposed. Then, on the basis of the optimization method of the cor... According to the traditional fatigue constant life curve, the concept and the universal expression of the generalized fatigue constant life curve were proposed. Then, on the basis of the optimization method of the correlation coefficient, the parameter estimation formulas were induced and the generalized fatigue constant life curve with the reliability level p was given. From P-S-a-S-m curve, the two-dimensional probability distribution of the fatigue limit was derived. After then, three se, of tests of LY11 CZ corresponding to the different average stress were carried out in terms of the two-dimensional up-down method. Finally, the methods are used to analyze the test results, and it is found that the analyzed results with the high precision may be obtained. 展开更多
关键词 fatigue limit generalized constant life curve two-dimensional up-down method
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Design of Software-Defined Down-Conversion and Up-Conversion: An Overview
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作者 Yue Zhang Li-Ke Huang +1 位作者 Carsten Maple Qing Xuan 《ZTE Communications》 2011年第4期10-14,共5页
In recent years, much attention has been paid to software-defined radio (SDR) technologies for multimode wireless systems SDR can be defined as a radio communication system that uses software to modulate and demodul... In recent years, much attention has been paid to software-defined radio (SDR) technologies for multimode wireless systems SDR can be defined as a radio communication system that uses software to modulate and demodulate radio signals. This article describes concepts, theory, and design principles for SDR down-conversion and up-conversion. Design issues in SDR down-conversion are discussed, and two different architectures, super-heterodyne and direct-conversion, are proposed. Design issues in SDR up-conversion are also discussed, and trade-offs in the design of filters, mixers, NCO, DAC, and signal processing are highlighted. 展开更多
关键词 SDR down-conversion UP-CONVERSION DIRECT-CONVERSION super-heterodyne conversion
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