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El Niño and the AMO Sparked the Astonishingly Large Margin of Warming in the Global Mean Surface Temperature in 2023
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作者 Kexin LI Fei ZHENG +1 位作者 Jiang ZHU Qing-Cun ZENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1017-1022,共6页
In 2023,the majority of the Earth witnessed its warmest boreal summer and autumn since 1850.Whether 2023 will indeed turn out to be the warmest year on record and what caused the astonishingly large margin of warming ... In 2023,the majority of the Earth witnessed its warmest boreal summer and autumn since 1850.Whether 2023 will indeed turn out to be the warmest year on record and what caused the astonishingly large margin of warming has become one of the hottest topics in the scientific community and is closely connected to the future development of human society.We analyzed the monthly varying global mean surface temperature(GMST)in 2023 and found that the globe,the land,and the oceans in 2023 all exhibit extraordinary warming,which is distinct from any previous year in recorded history.Based on the GMST statistical ensemble prediction model developed at the Institute of Atmospheric Physics,the GMST in 2023 is predicted to be 1.41℃±0.07℃,which will certainly surpass that in 2016 as the warmest year since 1850,and is approaching the 1.5℃ global warming threshold.Compared to 2022,the GMST in 2023 will increase by 0.24℃,with 88%of the increment contributed by the annual variability as mostly affected by El Niño.Moreover,the multidecadal variability related to the Atlantic Multidecadal Oscillation(AMO)in 2023 also provided an important warming background for sparking the GMST rise.As a result,the GMST in 2023 is projected to be 1.15℃±0.07℃,with only a 0.02℃ increment,if the effects of natural variability—including El Niño and the AMO—are eliminated and only the global warming trend is considered. 展开更多
关键词 record-breaking temperature global mean surface temperature El Niño AMO global warming
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In Tube Condensation:Changing the Pressure Drop into a Temperature Difference for a Wire-on-Tube Heat Exchanger
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作者 Louay Abd Al-Azez Mahdi Mohammed A.Fayad Miqdam T.Chaichan 《Fluid Dynamics & Materials Processing》 EI 2023年第9期2201-2214,共14页
A theoretical study based on the Penalty factor(PF)method by Cavallini et al.is conducted to show that the pressure drop occurring in a wire-on-tube heat exchanger can be converted into a temperature difference for tw... A theoretical study based on the Penalty factor(PF)method by Cavallini et al.is conducted to show that the pressure drop occurring in a wire-on-tube heat exchanger can be converted into a temperature difference for two types of refrigerants R-134a and R-600a typically used for charging refrigerators and freezers.The following conditions are considered:stratified or stratified-wavyflow condensation occurring inside the smooth tube of a wire-on-tube condenser with diameter 3.25,4.83,and 6.299 mm,condensation temperatures 35℃,45℃,and 54.4℃ and cover refrigerant massflow rate spanning the interval from 1 to 7 kg/hr.The results show that the PF variation is not linear with vapor quality and attains a maximum when the vapor quality is 0.2 and 0.18 for the R-134a and R-600a refrigerants,respectively.The PF increases with the refrigerant massflow rate if the inner diameter and saturation temperature constant,and it decreases on increasing the inner diameter to 6.299 mm for constant refrigerant massflow rate and saturation temperature.The PF for R-600a is higher than that for R-134a due to the lower saturation pressure in thefirst case.Furthermore,a stratifiedflow produces higher PF in comparison to the annularflow due to the effect of the surface tension. 展开更多
关键词 CONDENSATION penalty factor pressure drop temperature difference TWO-PHASE wire condenser
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New Results on One Modulo N-Difference Mean Graphs
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作者 Pon Jeyanthi Meganathan Selvi Damodaran Ramya 《Open Journal of Discrete Mathematics》 2023年第4期100-112,共13页
A graph G is said to be one modulo N-difference mean graph if there is an injective function f from the vertex set of G to the set , where N is the natural number and q is the number of edges of G and f induces a bije... A graph G is said to be one modulo N-difference mean graph if there is an injective function f from the vertex set of G to the set , where N is the natural number and q is the number of edges of G and f induces a bijection  from the edge set of G to given by and the function f is called a one modulo N-difference mean labeling of G. In this paper, we show that the graphs such as arbitrary union of paths, , ladder, slanting ladder, diamond snake, quadrilateral snake, alternately quadrilateral snake, , , , , friendship graph and admit one modulo N-difference mean labeling. 展开更多
关键词 Skolem difference mean Labeling One Modulo N-Graceful Labeling One Modulo N-difference mean Labeling and One Modulo N-difference mean Graph
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Record-breaking High-temperature Outlook for 2023: An Assessment Based on the China Global Merged Temperature(CMST) Dataset
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作者 Zichen LI Qingxiang LI Tianyi CHEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期369-376,共8页
According to the latest version(version 2.0) of the China global Merged Surface Temperature(CMST2.0) dataset, the global mean surface temperature(GMST) in the first half of 2023 reached its third warmest value since t... According to the latest version(version 2.0) of the China global Merged Surface Temperature(CMST2.0) dataset, the global mean surface temperature(GMST) in the first half of 2023 reached its third warmest value since the period of instrumental observation began, being only slightly lower than the values recorded in 2016 and 2020, and historically record-breaking GMST emerged from May to July 2023. Further analysis also indicates that if the surface temperature in the last five months of 2023 approaches the average level of the past five years, the annual average surface temperature anomaly in 2023 of approximately 1.26°C will break the previous highest surface temperature, which was recorded in 2016of approximately 1.25°C(both values relative to the global pre-industrialization period, i.e., the average value from 1850 to1900). With El Ni?o triggering a record-breaking hottest July, record-breaking average annual temperatures will most likely become a reality in 2023. 展开更多
关键词 CMST2.0 global mean surface temperature record-breaking temperature El Ni?o
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A rapid assessment of MWRI-RM/FY3G brightness temperature
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作者 Wenying He Xinran Xia +5 位作者 Shengli Wu Peng Zhang Hongbin Chen Xiang'ao Xia Yuquan Zhou Miao Cai 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第3期42-46,共5页
2023年4月发射的FY-3G上搭载17个频率的测雨微波成像仪(MWRI-RM),其业务定标的微波亮温(Tb)数据于2023年10月23日公开发布.本文比对了发布10天的MWRI-RM与全球降水测量(GPM)卫星上的微波成像仪(GMI)相匹配的Tb数据,并借助辐射传输模式... 2023年4月发射的FY-3G上搭载17个频率的测雨微波成像仪(MWRI-RM),其业务定标的微波亮温(Tb)数据于2023年10月23日公开发布.本文比对了发布10天的MWRI-RM与全球降水测量(GPM)卫星上的微波成像仪(GMI)相匹配的Tb数据,并借助辐射传输模式进行双差分(DD)交叉定标分析,旨在快速评估新一代MWRI-RM观测数据质量.观测比较表明,MWR1-RM与GMI测量的Tb一致性很好,大多通道的平均偏差(MBE)和均方根误差(RMSE)均小于1K.两种传感器由于观测角度略有不同在水面产生约0.5 K差异.DD分析也展示出MWRI-RM的大多数通道性能与GMI相当接近,尤其是首次启用的高频166 GHz和183 GHz. 展开更多
关键词 FY3G MWRI-RM GMI 亮度温度 双差分方法
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Temporal and spatial variation of annual mean air temperature in arid and semiarid region in northwest China over a recent 46 year period 被引量:24
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作者 Chen, ShaoYong Shi, YuanYuan +1 位作者 Guo, YuZhen Zheng, YanXiang 《Journal of Arid Land》 SCIE 2010年第2期87-97,共11页
We analyzed the 1961-2006 mean surface air temperature data of 138 stations in China’s northwest arid and semi-arid areas(CNASA),to measure climate change in terms of annual mean air temperature changes.We used metho... We analyzed the 1961-2006 mean surface air temperature data of 138 stations in China’s northwest arid and semi-arid areas(CNASA),to measure climate change in terms of annual mean air temperature changes.We used methods of linear regression analysis,multinomial fitting,Empirical Or-thogonal Function(EOF),Rotated Empirical Orthogonal Function(REOF),Mann-Kendall,Glide T-examination,wavelet analysis and power spectrum analysis.The results show that(1) the warming rate of the annual mean air temperature in CNASA was 0.35oC/10a during the 1961-2006 study period.Some places in the west part of Xinjiang and east part of the Qinghai plateau,which is impacted by the terrain of leeward slope,exhibit smaller increasing trends.However,the majority of region has shown distinct warming in line with general global warming;(2) The standard deviation of the annual mean temperature distribution is non-uniform.The south Xinjiang and east Qinghai-south Gansu areas show relatively small standard deviations,but the inter-annual variation in annual mean air temperature in the greater part of the region is high;(3) Inner Mongolia,Shaanxi,Gansu,Ningxia and Tarim Basin are the areas where the temperature changes are most sensitive to the environment.The degree of uniformity in annual mean air temperature increase is higher in the arid and semi-arid area.From the early 1970s,the trend in tempera-ture changed from a decrease to an increase,and there was a marked increase in mean temperature in 1986.After that mean temperature went through a period of rapid increase.The entire area’s 10 hottest years all occurred in or since the 1990s,and 90% of various sub-districts’ hottest years also occurred after 1990.The process of temperature change appears to have a roughly 5-year and a 10-year cycle;(4) An-nual mean air temperature variation has regional differences.In Inner Mongolia-Xinjiang and Shaanxi-Gansu-Ningxia-Qinghai areas,the temperature variation in their northern areas was very different from that in their southern areas;(5) Using the REOF method we divided the region into 4 sub-regions:the Northern region,the Plateau region,the Southern Xinjiang region and the Eastern region.The region’s annual mean air temperature transition has regional differences.The Plateau and Southern Xinjiang re-gions got warmer steadily without any obvious acceleration in the rate of warming.The Northern region’s warming started about 5-years earlier than that of the low latitude Eastern region.The ’Startup region’ of the Qinghai-Tibet Plateau,appears to undergo temperature changes 3 to 10 years earlier than the other regions,and exhibits inter-decadal variations 1 to 2 years ahead of the other regions. 展开更多
关键词 northwest area of China annual mean air temperature climatic warming
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On the relationship between convection intensity of South China Sea summer monsoon and air-sea temperature difference in the tropical oceans 被引量:12
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作者 LINAilan LIANGJianyin +1 位作者 GUDejun WANGDongxiao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2004年第2期267-278,共12页
The annual, interannual and inter-decadal variability of convection intensity of South China Sea (SCS) summer monsoon and air-sea temperature difference in the tropical ocean is analyzed, and their relationship is dis... The annual, interannual and inter-decadal variability of convection intensity of South China Sea (SCS) summer monsoon and air-sea temperature difference in the tropical ocean is analyzed, and their relationship is discussed using two data sets of 48-a SODA (simple ocean data assimilation) and NCEP/NCAR. Analyses show that in wintertime Indian Ocean (WIO), springtime central tropical Pacific (SCTP) and summertime South China Sea-West Pacific (SSCSWP), air-sea temperature difference is significantly associated with the convection intensity of South China Sea summer monsoon. Correlation of the inter-decadal time scale (above 10 a) is higher and more stable. There is inter-decadal variability of correlation in scales less than 10 a and it is related with the air-sea temperature difference itself for corresponding waters. The inter-decadal variability of the convection intensity during the South China Sea summer monsoon is closely related to the inter-decadal variability of the general circulation of the atmosphere. Since the late period of the 1970s, in the lower troposphere, the cross-equatorial flow from the Southern Hemisphere has intensified. At the upper troposphere layer, the South Asian high and cross-equatorial flow from the Northern Hemisphere has intensified at the same time. Then the monsoon cell has also strengthened and resulted in the reinforcing of the convection of South China Sea summer monsoon. 展开更多
关键词 tropical oceans air-sea temperature difference South China Sea summer monsoon convection Convec-tion intensity
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Changes and spatial patterns of the differences between ground and air temperature over the Qinghai-Xizang Plateau 被引量:5
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作者 ZHANG Wengang LI Shuxun +1 位作者 WU Tonghua PANG Qiangqiang 《Journal of Geographical Sciences》 SCIE CSCD 2007年第1期20-32,共13页
The difference between ground soil and air temperature (Ts-Ta) was studied by using the data of ground and air temperature of 99 stations over the Qinghai-Xizang (Tibet) Plateau from 1960 to 2000,and its spatial d... The difference between ground soil and air temperature (Ts-Ta) was studied by using the data of ground and air temperature of 99 stations over the Qinghai-Xizang (Tibet) Plateau from 1960 to 2000,and its spatial distribution and time changing tendency have been diagnosed by principal component analysis and power spectral analysis methods. The results show that the values of (Ts-Ta) are the maximum in June and the minimum in December. The first three loading eigenvectors, which reflect the main spatially anomalous structure of (Ts-Ta) over the Qinghai-Xizang Plateau, contain the contrary changing pattern between the northwestern and the southeastern regions, the pattern response of the sea level elevation and the geography, and the pattern response of the distribution of the permafrost. There are four patterns of time evolution including the patterns of monotonous increasing or decreasing trends, the basic stability pattern and the parabola pattern with the minimum value. (Ts-Ta) has a periodic variation about 2 years. According to the spatial distribution of the third loading eigenvectors of (Ts-Ta) over the Qinghai-Xizang Plateau in cold season, the permafrost response region and the seasonal frozen ground response region are identified. 展开更多
关键词 Qinghai-Xizang Plateau difference between ground and air temperature (Ts-Ta) principal component temperature subarea
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DETERMINATION OF WEIGHTED MEAN TROPOSPHERIC TEMPERATURE USING GROUND METEOROLOGICAL MEASUREMENTS 被引量:3
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作者 Liu Yanxiong Chen Yongqi Liu Jingnan 《Geo-Spatial Information Science》 2001年第1期14-18,共5页
The weighted mean tropospheric temperature is a critical parameter in the conversion of wet zenith delay to precipitable water vapor in GPS Meteorology.This parameter can not be calculated from the radiosonde data in ... The weighted mean tropospheric temperature is a critical parameter in the conversion of wet zenith delay to precipitable water vapor in GPS Meteorology.This parameter can not be calculated from the radiosonde data in real time through the conventional methods.In this study,we first discuss the admissible error of weighted mean temperature to enable the accuracy of the conversion better than 1 mm,then summarize the performance of some of the existing methods. An empirical formula is established that satisfies the real_time requirement in GPS meteorology using Sequential Regression Analysis method.It is shown that this real_time formula as compared with other empirical methods is more accurate for local applications. 展开更多
关键词 WEIGHTED mean TROPOSPHERIC temperature CONVERSION parameter SEQUENTIAL regression analysis
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Uniformity principle of temperature difference field in heat transfer optimization 被引量:1
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作者 程雪涛 梁新刚 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第6期245-253,共9页
The uniformity principle of temperature difference field is very useful in heat exchanger analyses and optimizations.In this paper, we analyze some other heat transfer optimization problems in the thermal management s... The uniformity principle of temperature difference field is very useful in heat exchanger analyses and optimizations.In this paper, we analyze some other heat transfer optimization problems in the thermal management system of spacecrafts,including the cooling of thermal components, the one-stream series-wound heat exchanger network, the volume-to-point heat conduction problem, and the radiative heat transfer optimization problem, and have found that the uniformity principle of temperature difference field also holds. When the design objectives under the given constraints are achieved, the distributions of the temperature difference fields are uniform. The principle reflects the characteristic of the distribution of potential in the heat transfer optimization problems. It is also shown that the principle is consistent with the entransy theory. Therefore, although the principle is intuitive and phenomenological, the entransy theory can be the physical basis of the principle. 展开更多
关键词 heat TRANSFER optimization UNIFORMITY PRINCIPLE of temperature difference field EQUIPARTITION of potential entransy theory
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On Cultural Differences between English and Chinese --From the Aspect of Seven Types of Meaning
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作者 刘海萍 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2002年第S1期312-314,共3页
This paper analyzes cultural differences of English and Chinese in terms of Seven Types of Meaning . It proceeds from the theory of Leech’s Seven Types of meaning , then comparatively illustrates with analysis of eac... This paper analyzes cultural differences of English and Chinese in terms of Seven Types of Meaning . It proceeds from the theory of Leech’s Seven Types of meaning , then comparatively illustrates with analysis of each type of meaning and cultural differences. And concludes with the cause of cultural differences and problems of it in cross-cultural communication with the hope that Chinese student could avoid Chinglish in learning and both Chinese and foreigners could avoid cultural shock when communicating with each other. 展开更多
关键词 cultural differences Chinese English seven types of meaning
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Solution precision of concrete temperature fields with finite difference method 被引量:1
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作者 张宇鑫 黄达海 刘海成 《Journal of Shanghai University(English Edition)》 CAS 2008年第4期302-305,共4页
With the finite difference method to calculate the temperature distribution in mass concrete structures, the solution precision will increase with a smaller step size, at the cost of computational time. In view of the... With the finite difference method to calculate the temperature distribution in mass concrete structures, the solution precision will increase with a smaller step size, at the cost of computational time. In view of the basic characteristics of the finite difference method, a simple yet powerful improvement is introduced. By multiplying the adiabatic temperature function with a correction factor, the precision of the solution can be assured without an increase in the computation time. In addition, the correction rules for three types of commonly used concrete hydration formulas are investigated. 展开更多
关键词 concrete structure temperature field finite difference method HYDRATION
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ON THE m^(th) ORDER DIFFERENCE SEQUENCE SPACE OF GENERALIZED WEIGHTED MEAN AND COMPACT OPERATORS 被引量:1
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作者 Metin BASARIR Emrah Evren KARA 《Acta Mathematica Scientia》 SCIE CSCD 2013年第3期797-813,共17页
In this article, using generalized weighted mean and difference matrix of order m, we introduce the paranormed sequence space l(u, v, p; △(m)), which consist of the sequences whose generalized weighted △(m)-di... In this article, using generalized weighted mean and difference matrix of order m, we introduce the paranormed sequence space l(u, v, p; △(m)), which consist of the sequences whose generalized weighted △(m)-difference means are in the linear space l(p) defined by I.J.Maddox. Also, we determine the basis of this space and compute its α-, β- and γ-duals. Further, we give the characterization of the classes of matrix mappings from l(u, v, p, △(m)) to l∞, c, and co. Finally, we apply the Hausdorff measure of noncompacness to characterize some classes of compact operators given by matrices on the space lp(U, v, △(m)) (1 ≤ p 〈 ∞). 展开更多
关键词 Paranormed sequence spaces difference sequence spaces weighted mean α- β γ-duals matrix mappings Hausdorff measure of noncompactness compactoperators
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Enhanced temperature difference control of distillation columns based on the averaged absolute variation magnitude 被引量:1
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作者 Yang Yuan Kejin Huang +3 位作者 Xing Qian Haisheng Chen Lijing Zang Liang Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第1期266-278,共13页
Temperature difference control(TDC)schemes can clearly suppress the adverse influence of pressure variations on product quality control of various distillation columns(DCs)by employing temperature differences(TDs)betw... Temperature difference control(TDC)schemes can clearly suppress the adverse influence of pressure variations on product quality control of various distillation columns(DCs)by employing temperature differences(TDs)between the sensitive stage temperature(T_(S))and reference stage temperature(T_(R)),i.e.,T_(S)-T_(R),to infer the controlled product qualities.However,because the TDC scheme has failed to specially take the corresponding relationship between the TD employed in each control loop and the controlled product quality into account,it may suffer from relatively large steady-state errors in the controlled product qualities.To address this problem,an enhanced TDC(ETDC)scheme is proposed in the current article,in which an enhanced TD(ETD),i.e.,T_(S)-α×T_(R),is employed to replace the conventional TD for each control loop.While the locations of the sensitive and reference stages of the ETD are respectively determined according to sensitivity analysis and SVD analysis,the adjusted coefficientαis set to be the ratio between the averaged absolute variation magnitudes(AAVMs)of the T_(S)and T_(R)so that the relationship between the T_(S)and T_(R)can be appropriately coordinated.With reference to the operations of three different distillation systems,i.e.,one conventional DC distilling an ethanol(E)/butanol(B)binary mixture,one conventional DC distilling an E/propanol(P)/B ternary mixture,and one dividing-wall distillation column distilling an E/P/B ternary mixture,the performance of the ETDC scheme is assessed by compared with the conventional TDC scheme and the double TD control(DTDC)scheme.The dynamic simulation results show that the ETDC scheme is better than the conventional TDC scheme with reduced steady-state errors in the controlled product qualities and improved dynamic responses,and is comparable with the DTDC scheme despite the less temperature measurements are employed. 展开更多
关键词 Distillation column temperature difference AAVM temperature inferential control Process control
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IMPROVEMENT OF REGIONAL PREDICTION OF SEA FOG ON GUANGDONG COASTLAND USING THE FACTOR OF TEMPERATURE DIFFERENCE IN THE NEAR-SURFACE LAYER 被引量:1
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作者 黄辉军 黄健 +2 位作者 刘春霞 毛伟康 毕雪岩 《Journal of Tropical Meteorology》 SCIE 2016年第1期66-73,共8页
The relationship between the factor of temperature difference of the near-surface layer(T_(1000 hPa)-T_(2m))and sea fog is analyzed using the NCEP reanalysis with a horizontal resolution of l°xl°(2000 to 201... The relationship between the factor of temperature difference of the near-surface layer(T_(1000 hPa)-T_(2m))and sea fog is analyzed using the NCEP reanalysis with a horizontal resolution of l°xl°(2000 to 2011) and the station observations(2010 to 2011).The element is treated as the prediction variable factor in the GRAPES model and used to improve the regional prediction of sea fog on Guangdong coastland.(1) The relationship between this factor and the occurrence of sea fog is explicit:When the sea fog happens,the value of this factor is always large in some specific periods,and the negative value of this factor decreases significantly or turns positive,suggesting the enhancement of warm and moist advection of air flow near the surface,which favors the development of sea fog.(2) The transportation of warm and moist advection over Guangdong coastland is featured by some stages and the jumping among these states.It also gets stronger over time.Meanwhile,the northward propagation of warm and moist advection is quite consistent with the northward advancing of sea fog from south to north along the coastland of China.(3) The GRAPES model can well simulate and realize the factor of near-surface temperature difference.Besides,the accuracy of regional prediction of marine fog,the relevant threat score and Heidke skill score are all improved when the factor is involved. 展开更多
关键词 weather prediction regional prediction of marine fog Guangdong coastland GRAPES model factor of near-surface temperature difference
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Study on the Influence of Piloti on Mean Radiant Temperature in Residential Blocks by 3-D Unsteady State Heat Balance Radiation Calculation 被引量:1
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作者 Tian-Yu Xi Jian-Hua Ding Hong Jin 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第4期91-95,共5页
Piloti is commonly used in tropical and subtropical climate zones to get high wind velocity and create shadowed areas in order to optimize the living environment of residential blocks,but there are few studies to reve... Piloti is commonly used in tropical and subtropical climate zones to get high wind velocity and create shadowed areas in order to optimize the living environment of residential blocks,but there are few studies to reveal the influence of piloti on the radiant environment of residential blocks systematically. Taking the city of Guangzhou as an example,using 3-D Unsteady State Heat Balance Radiation Calculation Method,this paper shows that the mean radiant temperature( MRT) under piloti area increases with the increase of piloti ratio,and especially when piloti ratio is equal to 100%,the MRT increase trend becomes sharp. The MRT of exposed area decreases with the increase of piloti ratio,especially when piloti ratio reaches 100%,the decrease trend of MRT becomes sharp,which offers the reference for the study on piloti design in subtropical climate zones and further research on living environment by CFD simulation in residential blocks. 展开更多
关键词 piloti mean radiant temperature 3-D unsteady state heat balance radiation calculation residential block
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Single Neuron PID Control Based on Expert Experiences for Temperature Difference Control System of a Digester 被引量:3
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作者 YaNan Huang AiJuan Zhang MuYi Hu 《Paper And Biomaterials》 2017年第1期52-58,共7页
Considering the temperature difference of displacement cooking characterized by severe non-linearity, large time delay, and real-time control, a cascade PID adaptive control strategy composed of a single neuron is pro... Considering the temperature difference of displacement cooking characterized by severe non-linearity, large time delay, and real-time control, a cascade PID adaptive control strategy composed of a single neuron is proposed to ensure cooking temperature uniformity. The control strategy introduces expert experiences to adjust the single neuron gain K, while a single neuron PID self-learning and adaptive ability, as well as cascade advantage can be combined to realize the real-time and fast temperature difference control. In the Simulink, the s-function of this control strategy is used to carry out a dynamic simulation experiment with temperature difference characteristics and verify the robustness and response to model mismatch. Compared to conventional temperature difference-flow PID cascade control and single neuron PID cascade control, this control strategy has better robustness and stronger adaptability. The results of real-time control on the THJSK-1 experiment platform indicate this control strategy is feasible. 展开更多
关键词 displacement cooking temperature difference expert experiences single neuron cascade PID
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Fast-moving target tracking based on mean shift and frame-difference methods 被引量:32
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作者 Hongpeng Yin Yi Chai +1 位作者 Simon X. Yang Xiaoyan Yang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第4期587-592,共6页
The mean shift tracker has difficulty in tracking fast moving targets and suffers from tracking error accumulation problem. To overcome the limitations of the mean shift method, a new approach is proposed by integrati... The mean shift tracker has difficulty in tracking fast moving targets and suffers from tracking error accumulation problem. To overcome the limitations of the mean shift method, a new approach is proposed by integrating the mean shift algorithm and frame-difference methods. The rough position of the moving tar- get is first located by the direct frame-difference algorithm and three-frame-difference algorithm for the immobile camera scenes and mobile camera scenes, respectively. Then, the mean shift algorithm is used to achieve precise tracking of the target. Several tracking experiments show that the proposed method can effectively track first moving targets and overcome the tracking error accumulation problem. 展开更多
关键词 mean shift frame-difference method target tracking computer vision.
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Applicability of Bevis Formula at Different Height Levels and Global Weighted Mean Temperature Model Based on Near-earth Atmospheric Temperature 被引量:14
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作者 Yibin YAO Zhangyu SUN Chaoqian XU 《Journal of Geodesy and Geoinformation Science》 2020年第1期1-11,共11页
Weighted mean temperature(T m)is a critical parameter in Global Navigation Satellite System(GNSS)technology to retrieve precipitable water vapor(PWV).It is convenient to obtain high-precision T m estimates near surfac... Weighted mean temperature(T m)is a critical parameter in Global Navigation Satellite System(GNSS)technology to retrieve precipitable water vapor(PWV).It is convenient to obtain high-precision T m estimates near surface utilizing Bevis formula and surface temperature.However,some researches pointed out that the Bevis formula has large uncertainties in high-altitude regions.We investigate the applicability of the Bevis formula at different height levels and find that the Bevis formula has relatively high precision when the altitude is low,while with altitude increasing,the precision decreases gradually.To solve the problem,we analyze the relationship between T m and atmospheric temperature within the near-earth space range(the height range between 0~10 km)and find that they have a high correlation on a global scale.Accordingly,we build a global weighted mean temperature model based on near-earth atmospheric temperature.Validation results of the model show that this model can provide high-precision T m estimation at any height level in the near-earth space range. 展开更多
关键词 weighted mean temperature Bevis FORMULA near-earth ATMOSPHERIC temperature GLOBAL model
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Homogenized Daily Mean/Maximum/Minimum Temperature Series for China from 1960-2008 被引量:88
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作者 LI Zhen YAN Zhong-Wei 《Atmospheric and Oceanic Science Letters》 2009年第4期237-243,共7页
Inhomogeneities in the daily mean/maximum/minimum temperature (T m /T max /T min) series from 1960 2008 at 549 National Standard Stations (NSSs) in China were analyzed by using the Multiple Analysis of Series for Homo... Inhomogeneities in the daily mean/maximum/minimum temperature (T m /T max /T min) series from 1960 2008 at 549 National Standard Stations (NSSs) in China were analyzed by using the Multiple Analysis of Series for Homogenization (MASH) software package.Typical biases in the dataset were illustrated via the cases of Bei-jing (BJ),Wutaishan (WT),ürümqi (UR) and Henan (HN) stations.The homogenized dataset shows a mean warm-ing trend of 0.261/0.193/0.344oC/decade for the annual series of T m /T max /T min,slightly smaller than that of the original dataset by 0.006/0.009/0.007oC/decade.However,considerable differences between the adjusted and origi-nal datasets were found at the local scale.The adjusted T min series shows a significant warming trend almost eve-rywhere for all seasons,while there are a number of sta-tions with an insignificant trend in the original dataset.The adjusted T m data exhibit significant warming trends annually as well as for the autumn and winter seasons in northern China,and cooling trends only for the summer in the middle reaches of the Yangtze River and parts of cen-tral China and for the spring in southwestern China,while the original data show cooling trends at several stations for the annual and seasonal scales in the Qinghai,Shanxi,Hebei,and Xinjiang provinces.The adjusted T max data exhibit cooling trends for summers at a number of stations in the mid-lower reaches of the Yangtze and Yellow Riv-ers and for springs and winters at a few stations in south-western China,while the original data show cooling trends at three/four stations for the annual/autumn periods in the Qinghai and Yunnan provinces.In general,the number of stations with a cooling trend was much smaller in the adjusted T m and T max dataset than in the original dataset.The cooling trend for summers is mainly due to cooling in August.The results of homogenization using MASH appear to be robust;in particular,different groups of stations with consideration of elevation led to minor effects in the results. 展开更多
关键词 每天平均数 / 最大值 / 最小温度系列 HOMOGENIZATION 中国 搅碎 气候趋势
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