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Local and Time Changes over a 66-Year Period and Annual Relocation of Saudi Arabian Subtropical High Pressure
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作者 Hasan Lashkari Ali Akbar Matkan Zainab Mohammadi 《Open Journal of Geology》 2016年第9期1080-1095,共16页
Saudi Arabian subtropical high pressure is a major system affecting general circulation of the atmosphere of west Asia. Its annual relocation affects the relocation of other systems in the area, such as Mediterranean ... Saudi Arabian subtropical high pressure is a major system affecting general circulation of the atmosphere of west Asia. Its annual relocation affects the relocation of other systems in the area, such as Mediterranean cyclones, Sudanese low pressure areas, and west wind waves. This system is known to relocate to the south and north in response to outward solar relocation, but the reasons behind its eastern and western relocation have not been studied thoroughly. The present study examined 1000 and 850 HPa levels over the course of 66 years (1948-2015) to determine a pattern of latitudinal and longitudinal relocation of the system using synoptic maps. The research showed that, after 2008, high pressure latitudinal and longitudinal swings were larger than in previous years and the annual high pressure relocation was not in concord with the apparent motion of the sun. At the onset of autumnal moderation, the high pressure core was positioned to the north of Saudi Arabia (22° - 30° north latitude and 42° - 50° south longitude). Southern movement continued until the end of March, when the core again relocated to the north. These relocations first occurred slowly, but the northern relocation occurred very quickly from May to June, such that the core moved northward 22° to 30°. After June, the core did not relocate much until the end of September. After September, it relocated strongly south in all time periods. It was noted that high pressure over Saudi Arabia had two cores from June to September in some years;in others the high pressure core was in southwestern Iran and Iraq. In still others, a southwest to northeast high pressure tab entered Iran from the southwest (Khuzestan) and continued northward with a core forming in the northern Caspian Sea. 展开更多
关键词 Analysis time and Local Change Subtropical High Pressure Saudi Arabia
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Proximal-distal motor unit number estimationdynamic changes in patients with amyotrophic lateral sclerosis A one-year follow-up
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作者 Sartucci Ferdinando Moscato Gianluca +5 位作者 Rossi Chiara Caleo Matteo Bocci Tommaso Murri Luigi Giannini Fabio Rossi Alessandro 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第8期597-601,共5页
BACKGROUND:Amyotrophic lateral sclerosis (ALS) is the most common of all the motor neuron diseases and the absence of a biologic marker has made both diagnosis and tracking evolution of the disease difficult, Elect... BACKGROUND:Amyotrophic lateral sclerosis (ALS) is the most common of all the motor neuron diseases and the absence of a biologic marker has made both diagnosis and tracking evolution of the disease difficult, Electrodiagnostic tests play a fundamental role in quantifying pathological changes in the motor unit pool.OBJECTIVE:We assessed distal-proximal Motor Unit (MU) loss and changes using the method of motor unit number estimation (MUNE).DESIGN, TIME AND SETTING:A case-control study was performed at the Department of Neuroscience, Pisa University Medical School, Italy from December 1999 to November 2009. PARTICIPANTS:A total of 50 ALS patients were recruited, 30 males:mean age (59.6 ± 13.3) years; 20 females:mean age (63.9 ± 11.7) years; range (30-82) years; all patients had probable or definite ALS. Thirty healthy volunteers were recruited from department staffs, including 20 males and 10 females; mean age (57.7 ± 13.8) years served as controls.METHODS:MUNE was performed for both the biceps brachii and abductor digiti minimi muscles of the same side. The technique used relayed substantially on manual incremental stimulation of the motor nerve, known as the McComas technique (50 ms sweep duration, a gain of 2 mV/Div for M wave, 0.5 mV/Div for each step; filters 10-20 kHz).MAIN OUTCOME MEASURES:MUNE results were measured.RESULTS:Functioning MU numbers, measured by MUNE, decreased in the biceps brachii and abductor digiti minimi muscles over the entire one-year follow-up period (one assessment every three months) compared with baseline determination, the rate of MU decrease was similar in both muscles, but steeper distally.CONCLUSION:MUNE is a feasible method for ALS patients both proximally and distally to track changes over time in muscle MUs during the disease's evolution. 展开更多
关键词 motor unit number estimation amyotrophic lateral sclerosis motor neuron disease time changes DENERVATION REINNERVATION
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Nighttime meridional neutral wind responses to SAPS simulated by the TIEGCM:A universal time effect 被引量:1
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作者 KeDeng Zhang Hui Wang +3 位作者 WenBin Wang Jing Liu ShunRong Zhang Cheng Sheng 《Earth and Planetary Physics》 CSCD 2021年第1期52-62,共11页
The present work uses the Thermosphere Ionosphere Electrodynamics General Circulation Model(TIEGCM),under geomagnetically disturbed conditions that are closely related to the southward interplanetary magnetic field(IM... The present work uses the Thermosphere Ionosphere Electrodynamics General Circulation Model(TIEGCM),under geomagnetically disturbed conditions that are closely related to the southward interplanetary magnetic field(IMF),to investigate how the nighttime poleward wind(30°–50°magnetic latitude and 19–22 magnetic local time)responds to subauroral polarization streams(SAPS)that commence at different universal times(UTs).The SAPS effects on the poleward winds show a remarkable UT variation,with weaker magnitudes at 00 and 12 UT than at 06 and 18 UT.The strongest poleward wind emerges when SAPS commence at 06 UT,and the weakest poleward wind develops when SAPS occur at 00 UT.A diagnostic analysis of model results shows that the pressure gradient is more prominent for the developing of the poleward wind at 00 and 12 UT.Meanwhile,the effect of ion drag is important in the modulation of the poleward wind velocity at 06 and 18 UT.This is caused by the misalignment of the geomagnetic and geographic coordinate systems,resulting in a large component of ion drag in the geographically northward(southward)direction due to channel orientation of the SAPS at 06 and 18 UT(00 and 12 UT).The Coriolis force effect induced by westward winds maximizes(minimizes)when SAPS commence at 12 UT(00 UT).The centrifugal force due to the accelerated westward winds shows similar UT variations as the Coriolis force,but with an opposite effect. 展开更多
关键词 Subauroral Polarization Streams TIEGCM poleward winds Universal time change
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Climate Change Crunch Time
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《ChinAfrica》 2011年第11期10-11,共2页
From November 28 to December 9,the 17th Conference of the Parties(COP17) to the United Nations Framework Convention on Climate Change takes place in Durban,South Africa.Discussions will center on what the internationa... From November 28 to December 9,the 17th Conference of the Parties(COP17) to the United Nations Framework Convention on Climate Change takes place in Durban,South Africa.Discussions will center on what the international community can do to cope with the increasingly serious climate change.In an article for China Today,Xie Zhenhua, Vice Chairman of National Development and Reform Commission,explained China’s efforts in carbon emission reduction and its stance at the upcoming conference.His edited views follow: 展开更多
关键词 Climate Change Crunch time
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Study on a gravity precursor mode of the M_S=7.0 Lijiang earthquake 被引量:2
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作者 申重阳 李辉 傅广裕 《Acta Seismologica Sinica(English Edition)》 CSCD 2003年第2期175-184,共10页
To study the seismogeny process or the precursory behavior of the 1976 MS=7.0 Lijiang earthquake, we analyze the repeat gravity data with high precision from the Western Yunnan Earthquake Prediction Experiment Area (W... To study the seismogeny process or the precursory behavior of the 1976 MS=7.0 Lijiang earthquake, we analyze the repeat gravity data with high precision from the Western Yunnan Earthquake Prediction Experiment Area (WYEPEA) and the related results of geology and geophysics survey in this paper. Considering the gross errors caused by observation data and model difference, we have firstly inverted the slip distribution of the main active faults with time based on the robust Bayesian least squares estimation and multi-fault dislocation model. The re-sults show that the slip changes of the faults with time from 1990 to 1997 obviously reflect the preparation process of the Lijiang earthquake. The images of main precursor mode have the characteristic of main shock-after shock type, which is agreement to the model of coupling movement between crust density and crust deformation (DD mode of coupling movement). 展开更多
关键词 Lijiang earthquake repeat gravity observation precursor mode time changes of faults slip +
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Climate Change of 4℃ Global Warming above Pre-industrial Levels 被引量:6
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作者 Xiaoxin WANG Dabang JIANG Xianmei LANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第7期757-770,共14页
Using a set of numerical experiments from 39 CMIP5 climate models, we project the emergence time for 4?C global warming with respect to pre-industrial levels and associated climate changes under the RCP8.5 greenhouse... Using a set of numerical experiments from 39 CMIP5 climate models, we project the emergence time for 4?C global warming with respect to pre-industrial levels and associated climate changes under the RCP8.5 greenhouse gas concentration scenario. Results show that, according to the 39 models, the median year in which 4?C global warming will occur is 2084.Based on the median results of models that project a 4?C global warming by 2100, land areas will generally exhibit stronger warming than the oceans annually and seasonally, and the strongest enhancement occurs in the Arctic, with the exception of the summer season. Change signals for temperature go outside its natural internal variabilities globally, and the signal-tonoise ratio averages 9.6 for the annual mean and ranges from 6.3 to 7.2 for the seasonal mean over the globe, with the greatest values appearing at low latitudes because of low noise. Decreased precipitation generally occurs in the subtropics, whilst increased precipitation mainly appears at high latitudes. The precipitation changes in most of the high latitudes are greater than the background variability, and the global mean signal-to-noise ratio is 0.5 and ranges from 0.2 to 0.4 for the annual and seasonal means, respectively. Attention should be paid to limiting global warming to 1.5?C, in which case temperature and precipitation will experience a far more moderate change than the natural internal variability. Large inter-model disagreement appears at high latitudes for temperature changes and at mid and low latitudes for precipitation changes. Overall, the intermodel consistency is better for temperature than for precipitation. 展开更多
关键词 4℃ global warming timing climate change signal-to-noise ratio uncertainty
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Monitoring of Soil Bulk Density in Context with Its Small-Scale Spatial Heterogeneity 被引量:1
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作者 Miloš Širáň Jarmila Makovníková 《Journal of Geoscience and Environment Protection》 2021年第5期138-151,共14页
The main aim of soil monitoring system is to obtain the knowledge of the most current state and development of soil properties according to concrete threats to soil. To determine the significant changes of soil proper... The main aim of soil monitoring system is to obtain the knowledge of the most current state and development of soil properties according to concrete threats to soil. To determine the significant changes of soil properties in time, it is important to know spatial variability of concrete soil parameter for concrete site. Only those time changes of the soil parameter are significant, which exceed its spatial variability at the site. The main aim of the study has been focused on the evaluation of small-scale site heterogeneity of equilibrium soil bulk density and the integration of impact of this heterogeneity in evaluation of degradation process of soil compaction in time. As site variation coefficients have considerably varied at standard sampling with five repetitions during monitoring period, one-time detail spatial variability mapping of soil bulk density was realized at 17 repetitions on five selected monitoring sites with different soil type, texture and use. This increase in the number of sampling points helped us to specify and stabilize the values of variation coefficients (between minimum and maximum by standard sampling) as well as the extent of confidence intervals. Standard deviations at the chosen monitoring sites moved from 0.039 to 0.118 g·cm<sup><span style="font-family:Verdana;"><span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#ffffff;"="">-</span>3</span></sup><span style="font-family:Verdana;"> in topsoil and from 0.031 to 0.067 g·cm</span><sup><span style="font-family:Verdana;"><span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#ffffff;"="">-</span>3</span></sup><span style="font-family:Verdana;"> in subsoil and expressed as variation coefficient 2.9% - 9.2% and 2.0% - 4.9%, respectively. The intervals of significant time changes of soil bulk density for the sites and depths were determined on the base of its site confidence interval (95%) and uncertainty rate of its measure methodology. The time changes of bulk density values between single year-to-year sampling were overlapped by this interval of significant changes to obtain significant bulk density changes in time. This method allowed us to distinguish significant time changes in soil bulk density from insignificant ones. The bulk density value changes on the monitoring sites were significant in the range of six to nine years within observed period 2002-2014 in both depths.</span> 展开更多
关键词 Soil Monitoring Soil Bulk Density SPATIAL Site and time Variability Significant time Change
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Three-order pseudo-Hamilton canonical equationsReceived
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作者 马善钧 黄沛天 +1 位作者 颜蓉 赵红霞 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第10期2193-2196,共4页
Based on the three-order Lagrangian equations, Hamilton's function of acceleration H^* and generalized acceleration momentum P^*α are defined, and pseudo-Hamilton canonical equations corresponding to three-order L... Based on the three-order Lagrangian equations, Hamilton's function of acceleration H^* and generalized acceleration momentum P^*α are defined, and pseudo-Hamilton canonical equations corresponding to three-order Lagrangian equations are obtained. The equations are similar to Hamilton's canonical equations of analytical mechanics in form. 展开更多
关键词 three-order Lagrangian equations pseudo-Hamilton canonical equations time rate of change of force
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中国平视世界的重大时代意义
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作者 阮宗泽 《Contemporary International Relations》 2021年第5期40-63,共24页
A resurgent China contributes to the world. General Secretary Xi Jinping attaches great importance to the issues of the times and analyzes the development direction of humankind from the perspective and method of Marx... A resurgent China contributes to the world. General Secretary Xi Jinping attaches great importance to the issues of the times and analyzes the development direction of humankind from the perspective and method of Marxism. Further, he indicates that we must base ourselves on the overall strategy of the great rejuvenation of the Chinese nation and the significant changes occurring in the world that have not been seen in a century and makes a major judgment that the timing and international situation are favorable to China. Inevitably, Chinese now view themselves as equals of any other in the world, reflecting a historic change in the relations between China and the remaining world. In other words, no country can dictate terms to China. Building a powerful modern socialist country is a great goal set by the Communist Party of China(CPC). To build a great country and achieve a great cause, we must go through enormous struggle. Xi Jinping Thought on Diplomacy reflects on the issues of our times. Answering the questions and guiding the changes of our times, Xi Jinping Thought on Diplomacy is of great significance. Moreover, the CPC has remained true to socialism, and socialism has proved its worth to China. 展开更多
关键词 China the world Xi Jinping's diplomatic thought the change of the times
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Reading Faces——Our definition of what's normal changes over time
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作者 Temma Ehrenfeld 吕云 《当代外语研究》 2004年第7期34-35,共2页
爱美之心,人皆有之,但研究人员发现:Individual and social attitudes to-ward what’s acceptable,and what’s beautiful,change over time,因此尽管有Survival of the Prettiest(靓者生存)的说法,在目前轰轰烈烈的“人造”美女与帅... 爱美之心,人皆有之,但研究人员发现:Individual and social attitudes to-ward what’s acceptable,and what’s beautiful,change over time,因此尽管有Survival of the Prettiest(靓者生存)的说法,在目前轰轰烈烈的“人造”美女与帅哥的潮流中,是否选择plastic-surgery(整形手术)最好还是三思而行。 展开更多
关键词 Our definition of what’s normal changes over time Reading Faces
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The Existence and Uniqueness of a New Boundary Value Problem(Type of Problem“E”)for a Class of Semi Linear(Power Type Nonlinearities)Mixed Hyperbolic-Elliptic System Equations of Keldysh Type with Changing Time Direction 被引量:1
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作者 Mahammad A.NURMAMMADOV 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2022年第4期763-777,共15页
In present work studied the new boundary value problem for semi linear(Power-type nonlinearities)system equations of mixed hyperbolic-elliptic Keldysh type in the multivariate dimension with the changing time directio... In present work studied the new boundary value problem for semi linear(Power-type nonlinearities)system equations of mixed hyperbolic-elliptic Keldysh type in the multivariate dimension with the changing time direction.Considered problem and equation belongs to the modern level partial differential equations.Applying methods of functional analysis,topological methods,“ε”-regularizing.and continuation by the parameter at the same time with aid of a prior estimates,under assumptions conditions on coefficients of equations of system,the existence and uniqueness of generalized and regular solutions of a boundary problem are established in a weighted Sobolev's space.In this work one of main idea consists of show that the new boundary value problem which investigated in case of linear system equations can be well-posed when added nonlinear terms to this linear system equations,moreover in this case constructed new weithged spaces,the identity between of strong and weak solutions is established. 展开更多
关键词 changing time direction weighted Sobolev space equation of mixed type strong weak and regular solution eqution of Keldysh type
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Functional inequalities for time-changed symmetric α-stable processes
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作者 Jian WANG Longteng ZHANG 《Frontiers of Mathematics in China》 SCIE CSCD 2021年第2期595-622,共28页
We establish sharp functional inequalities for time-changed symmetric α-stable processes on Rd with d≥1 and α∈(0,2), which yield explicit criteria for the compactness of the associated semigroups. Furthermore, whe... We establish sharp functional inequalities for time-changed symmetric α-stable processes on Rd with d≥1 and α∈(0,2), which yield explicit criteria for the compactness of the associated semigroups. Furthermore, when the time change is defined via the special function W(x)=(1+|x|)β with β>α we obtain optimal Nash-type inequalities, which in turn give us optimal upper bounds for the density function of the associated semigroups. 展开更多
关键词 Symmetricα-stable process time change functional inequality
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Fisher's perceptions about a marine protected area over time
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作者 Cristina Pita Barbara Horta e Costa +5 位作者 Gustavo Franco Rui Coelho Inês Sousa Emanuel J.Gonçalves Jorge M.S.Gonçalves Karim Erzini 《Aquaculture and Fisheries》 2020年第5期273-281,共9页
The perceptions of fishers towards the Arrábida Marine Park,a marine protected area(MPA)in the west coast of Portugal,were studied through face-to-face interviews in two different moments of the MPA life cycle.Fi... The perceptions of fishers towards the Arrábida Marine Park,a marine protected area(MPA)in the west coast of Portugal,were studied through face-to-face interviews in two different moments of the MPA life cycle.Fishers'perceptions about the MPA and the impact it had on the fishing activity over time were identified just before the full implementation of the zoning and regulations of the management plan and 10 years later.This study aimed to investigate fishers'knowledge,acceptance and perceptions about the MPA changed with time,if support for the MPA was linked to the impact of the MPA on the fishing activity,and if fishers'perceptions about the impact of the MPA on the fishing activity match with local landings trends.Results show that although knowledge about the marine park significantly improved over time,fishers'acceptance did not.A decrease on fishers'support was not substantial but occurred.Issues such as the disagreement with regulations reinforced concerns raised during the implementation of the marine park,particularly in relation to the top-down decision-making,which commonly confers minor participation,recognition and legitimacy to fishers.Apparently,fisheries benefits were still not perceived by local fishers,though they are central for fishers'support.Further,the perceived negative impacts of the park seemed to be more related to social aspects and individual interests than to impacts on catches.Addressing adequate management,enforcement and participation of local fishers is still possible and are advocated here as to contribute to the expected socioecological outcomes and respective support,leading to the future successful performance of the Arrábida Marine Park.Assessing fishers’perceptions towards an MPA over time is central and should be included on periodical socioecological monitoring and inform an effective adaptive management. 展开更多
关键词 Arrabida Marine Park(AMP) Local fisheries PERCEPTIONS ATTITUDES Fishers'support Decision-making Marine protected area changes over time
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It's Time for a Change in Linguistics—a Brief Review of the 18th International Systemic Congress
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作者 Yang Chaoguang 《国际商务(对外经济贸易大学学报)》 CSSCI 1992年第1期62-63,共2页
About the CongressThe 18th International Systemic Congress was convened in Tokyo,Japanfrom 29th July to 2nd August 1991.It took place on the ever-green garden-like campus of the International Christian University,with... About the CongressThe 18th International Systemic Congress was convened in Tokyo,Japanfrom 29th July to 2nd August 1991.It took place on the ever-green garden-like campus of the International Christian University,with more than onehundred participants from about twenty countries and regions.Among 展开更多
关键词 a Brief Review of the 18th International Systemic Congress It’s time for a Change in Linguistics
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Changing the World,One City at a Time
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《Beijing Review》 2007年第38期24-24,共1页
In this series,Beijing Review will profile several "sister city" relationships between the United States and China.Washington,D.C.-based Sister Cities International facilitates the city pairings,as part of a... In this series,Beijing Review will profile several "sister city" relationships between the United States and China.Washington,D.C.-based Sister Cities International facilitates the city pairings,as part of a 50-year-old mission to promote"citizen diplomacy."Our first sister city profile is on Pasadena,California and its counterpart Xicheng District in Beijing. 展开更多
关键词 World Changing the World One City at a time
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IH&RA 40th Annual Congress: 5-9 December 2003 Cairo, Egypt“Managing Through Rapidly Changing Times” See Update of High-Powered Conference Speakers
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《饭店现代化》 2003年第5期23-23,共1页
关键词 2003 Egypt Managing Through Rapidly Changing times See Update of High-Powered Conference Speakers December 2003 Cairo IH&RA 40th Annual Congress RA of
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The Times are Changing Women's Employment
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作者 LIU BOHONG Associate Professor of the Women’s Studies Institute of China of the All-China Women’s Federation 《Women of China》 1995年第6期20-21,共2页
IN the mid- and late-1980s a debate was held in China concerning the issue of women’s employment. It was a time when economic reform involved both the management and labor force of the country’s state-rum enterprise... IN the mid- and late-1980s a debate was held in China concerning the issue of women’s employment. It was a time when economic reform involved both the management and labor force of the country’s state-rum enterprises. What the Chinese women in the workforce had experienced from the late 1980s to the early 1990s in many ways differed from our predictions about the debate. Perhaps we can make a closer analysis of the trend in Chinese women’s employment by learning the differences. Both the employment rate and the population of Chinese women in urban and rural areas have steadily grown as the economy has developed. In 1982 the Chinese workforce 展开更多
关键词 The times are Changing Women’s Employment
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CHALLENGES TO TEACHERS AT A TIME OF CURRICULUM CHANGE
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《Chinese Journal of Applied Linguistics》 1998年第2期31-33,共3页
This paper introduces the background of English curriculum change an the serious problems related to the reform of English teaching in the P. R. China. It analyses the major expectation of the curriculum designers and... This paper introduces the background of English curriculum change an the serious problems related to the reform of English teaching in the P. R. China. It analyses the major expectation of the curriculum designers and the teachers during implementation. It also discusses the great challenge to teachers in terms of conceptions and practices. 展开更多
关键词 CHALLENGES TO TEACHERS AT A time OF CURRICULUM CHANGE AT
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Stability of elliptic Harnack inequalities Dedicated to Professor Jia-an Yan on the Occasion of His 80th Birthday
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作者 Zhen-Qing Chen 《Science China Mathematics》 SCIE CSCD 2023年第10期2179-2190,共12页
We survey some recent progress in the study of stability of elliptic Harnack inequalities under form-bounded perturbations for strongly local Dirichlet forms on complete locally compact separable metric spaces.
关键词 elliptic Harnack inequality Green function metric doubling good doubling measure Dirichlet form relative capacity time change
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The valuation of barrier options under a threshold rough Heston model
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作者 Kevin Z.Tong Allen Liu 《Journal of Management Science and Engineering》 CSCD 2023年第1期15-31,共17页
In this paper,we propose a novel model for pricing double barrier options,where the asset price is modeled as a threshold geometric Brownian motion time changed by an integrated activity rate process,which is driven b... In this paper,we propose a novel model for pricing double barrier options,where the asset price is modeled as a threshold geometric Brownian motion time changed by an integrated activity rate process,which is driven by the convolution of a fractional kernel with the CIR process.The new model both captures the leverage effect and produces rough paths for the volatility process.The model also nests the threshold diffusion,Heston and rough Heston models.We can derive analytical formulas for the double barrier option prices based on the eigenfunction expansion method.We also implement the model and numerically investigate the sensitivities of option prices with respect to the parameters of the model. 展开更多
关键词 Rough stochastic volatility Threshold diffusion Barrier options Eigenfunction expansion Stochastic time change
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