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Driving factors of CO_(2)emissions in South American countries:An application of Seemingly Unrelated Regression model
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作者 Gadir BAYRAMLI Turan KARIMLI 《Regional Sustainability》 2024年第4期120-132,共13页
Carbon emissions have become a critical concern in the global effort to combat climate change,with each country or region contributing differently based on its economic structures,energy sources,and industrial activit... Carbon emissions have become a critical concern in the global effort to combat climate change,with each country or region contributing differently based on its economic structures,energy sources,and industrial activities.The factors influencing carbon emissions vary across countries and sectors.This study examined the factors influencing CO_(2)emissions in the 7 South American countries including Argentina,Brazil,Chile,Colombia,Ecuador,Peru,and Venezuela.We used the Seemingly Unrelated Regression(SUR)model to analyse the relationship of CO_(2)emissions with gross domestic product(GDP),renewable energy use,urbanization,industrialization,international tourism,agricultural productivity,and forest area based on data from 2000 to 2022.According to the SUR model,we found that GDP and industrialization had a moderate positive effect on CO_(2)emissions,whereas renewable energy use had a moderate negative effect on CO_(2)emissions.International tourism generally had a positive impact on CO_(2)emissions,while forest area tended to decrease CO_(2)emissions.Different variables had different effects on CO_(2)emissions in the 7 South American countries.In Argentina and Venezuela,GDP,international tourism,and agricultural productivity significantly affected CO_(2)emissions.In Colombia,GDP and international tourism had a negative impact on CO_(2)emissions.In Brazil,CO_(2)emissions were primarily driven by GDP,while in Chile,Ecuador,and Peru,international tourism had a negative effect on CO_(2)emissions.Overall,this study highlights the importance of country-specific strategies for reducing CO_(2)emissions and emphasizes the varying roles of these driving factors in shaping environmental quality in the 7 South American countries. 展开更多
关键词 CO_(2)emissions Urbanization INDUSTRIALIZATION International tourism Agricultural productivity Seemingly Unrelated Regression(SUR)model South American countries
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Active tectonics in Taiwan:insights from a 3-D viscous finite element model
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作者 Yujun Sun Mian Liu +2 位作者 Shuwen Dong Huai Zhang Yaolin Shi 《Earthquake Science》 CSCD 2015年第5期353-363,共11页
Taiwan is a young orogenic belt with complex spatial distributions of deformation and earthquakes. We have constructed a three-dimensional finite element model to explore how the interplays between lithospheric struc-... Taiwan is a young orogenic belt with complex spatial distributions of deformation and earthquakes. We have constructed a three-dimensional finite element model to explore how the interplays between lithospheric struc- ture and plate boundary processes control the distribution of stress and strain rates in the Taiwan region. The model assumes a liberalized power-law rheology and incorporates main lithospheric structures; the model domain is loaded by the present-day crustal velocity applied at its bound- aries. The model successfully reproduces the main features of the GPS-measured strain rate patterns and the earth- quake-indicated stress states in the Taiwan region. The best fitting model requires the viscosity of the lower crust to be two orders of magnitude lower than that of the upper crust and lithospheric mantle. The calculated deviatoric stress is high in regions of thrust faulting and low in regions of extensional and strike-slip faulting, consistent with the spatial pattern of seismic intensity in Taiwan. 展开更多
关键词 taiwan STRESS Strain rate FEM model EARTHQUAKE
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Adapting chronic care models for diabetes care delivery in low-and-middle-income countries:A review
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作者 Grace Marie V Ku Guy Kegels 《World Journal of Diabetes》 SCIE CAS 2015年第4期566-575,共10页
A contextual review of models for chronic care was done to develop a context-adapted chronic care model-based service delivery model for chronic conditions including diabetes.The Philippines was used as the setting of... A contextual review of models for chronic care was done to develop a context-adapted chronic care model-based service delivery model for chronic conditions including diabetes.The Philippines was used as the setting of a low-to-middle-income country.A context-based narrative review of existing models for chronic care was conducted.A situational analysis was done at thegrassroots level,involving the leaders and members of the community,the patients,the local health system and the healthcare providers.A second analysis making use of certain organizational theories was done to explore on improving feasibility and acceptability of organizing care for chronic conditions.The analyses indicated that care for chronic conditions may be introduced,considering the needs of people with diabetes in particular and the community in general as recipients of care,and the issues and factors that may affect the healthcare workers and the health system as providers of this care.The context-adapted chronic care model-based service delivery model was constructed accordingly.Key features are:incorporation of chronic care in the health system's services; assimilation of chronic care delivery with the other responsibilities of the healthcare workers but with redistribution of certain tasks; and ensuring that the recipients of care experience the whole spectrum of basic chronic care that includes education and promotion in the general population,risk identification,screening,counseling including self-care development,and clinical management of the chronic condition and any co-morbidities,regardless of level of control of the condition.This way,low-to-middle income countries can introduce and improve care for chronic conditions without entailing much additional demand on their limited resources. 展开更多
关键词 Chronic care models Context adaptation DIABETES MELLITUS type 2 Low-to-middle INCOME COUNTRIES Service delivery model
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Improved stress release model: Application to the study of earthquake prediction in Taiwan Region
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作者 朱守彪 石耀霖 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2002年第2期171-178,共8页
Stress release model used to be applied to seismicity study of large historical earthquakes in a space of large scale. In this paper, we improve the stress release model, and discuss whether the stress release model i... Stress release model used to be applied to seismicity study of large historical earthquakes in a space of large scale. In this paper, we improve the stress release model, and discuss whether the stress release model is still applicable or not in the case of smaller spatio-temporal scale and weaker earthquakes. As an example of testing the model, we have analyzed the M greater than or equal 6 earthquakes in recent about 100 years. The result shows that the stress release model is still applicable. The earthquake conditional probability intensity in Taiwan Region is calculated with the improved stress release model. We see that accuracy of earthquake occurrence time predicted by the improved stress release model is higher than that by Poisson model in the test of retrospect earthquake prediction. 展开更多
关键词 improved stress release model conditional probability intensity Poisson model taiwan Region
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Model for Predicting the Transport and Dispersal of Contaminants Incoming with Submarine Groundwater: Case Study for the Southwestern Taiwan Coastal Zone
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作者 Konstantin A. Korotenko Peter O. Zavialov +1 位作者 Ruey-Chy Kao Chung-Feng Ding 《Open Journal of Marine Science》 2012年第2期70-83,共14页
As was recognized recently, the submarine groundwater transports a significant amount of various contaminants into the coastal ocean. An assessment of the impact of intruded pollutants in the coastal ecosystems requir... As was recognized recently, the submarine groundwater transports a significant amount of various contaminants into the coastal ocean. An assessment of the impact of intruded pollutants in the coastal ecosystems requires understanding fate of the pollutants and processes of their dispersal in ambient waters. In this paper, we proposed a 3-D coupled ocean circulation/particle-tracking model for predicting the transport and dispersal of pollution-containing groundwater discharged into a coastal environment of the southwestern Taiwan. The particle-tracking model takes currents and turbulent diffusivities predetermined by the ocean circulation model and uses the Lagrangian approach to predict the motion of individual droplets, the sum of which constitutes a contaminant plume in result of discharge of contaminant-rich submarine groundwater. The ocean circulation model was forced by tides and seasonal favorable winds for the south-western coast of Taiwan. The initialization of the coupled model was set using field data obtained in 2009 on the Ping-tung shelf where shallow aquifer seepages were discovered. Several types of numerical experiment scenarios were set up to elucidate the transport and dispersal of conservative and nonconservative (nitrate) contaminants in the shallow coastal zone. The comparison of obtained numerical results with observations performed by other researches was discussed. 展开更多
关键词 SUBMARINE GROUNDWATER Coastal Zone NITRATE Eulerian-Lagrangian model taiwan
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Modeling the Impact of Mine and Country Variations on the Cost and Country-Benefit of Gold Mining
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作者 Karim Baruti Antipas T. S. Massawe Beatus Alois Kundi 《Engineering(科研)》 2011年第2期174-186,共13页
This paper dwells on regression models of cash-cost and country-benefit developed to enable accounting for the cumulative impact of the determinant parameters in the prediction of cash-costs and country-benefits of go... This paper dwells on regression models of cash-cost and country-benefit developed to enable accounting for the cumulative impact of the determinant parameters in the prediction of cash-costs and country-benefits of gold mining opportunities in the justification of taxation regimes and selection of investment targets worldwide. The data used in the generation of regression models include the total cash-cost and country-benefit per ounce vs the parameters of rock-mass (type of ore body, its dip angle, strike length and thickness), mine-design (rate of gold production, type of mine, depth of mine, gold price and age of mine) and country parameters (the Fraser Institute parameters: taxation regime, infrastructure, environmental regime, political stability, labor regulations and security) were generated from 160 gold mines in the top 20 gold rich countries for a period of 7 years from 2002 to 2008. The regression models show that the determinants account for 71% and 55% of the determinants of cash-cost and country-benefit respectively. Depending on the availability of data, the regression models generated in this study could be enhanced by adding into the parameters used in the regression analysis, the unaccounted for mine and country parameters. Also, Depending on the availability of data, the Regression models generated in this study could be enhanced further by replacing the parameters of Fraser Institute ranking used in the regression analysis with the actual parameters of country effect on cash-cost and country-benefit of the gold produced. Nevertheless, the regression models generated in this study could be used to predict the cash-costs and country-benefits of gold mining opportunities in the justification of taxation regimes and selection of investment targets worldwide. 展开更多
关键词 Rock-Mass PARAMETERS Mine-Design PARAMETERS country PARAMETERS Regression models
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Quantificational analysis and simulation of Technical Barriers to Trade with two country model
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作者 JIANG Jian-ye WANG Ding-wei 《Chinese Business Review》 2009年第6期37-43,共7页
The Technical Barriers to Trade (TBT) is an important problem faced to the export of China. Based on the number differences of TBT notifications between countries, we propose the concept and computational method of ... The Technical Barriers to Trade (TBT) is an important problem faced to the export of China. Based on the number differences of TBT notifications between countries, we propose the concept and computational method of the technical barrier coefficient. By means of price-production and price-demand functions, a trade model with a developed country and a developing country is designed. The available trade policies such as technical barriers, tariffs and export subsidies are simulated and analyzed. According to the simulation results, several trade strategies to come over technical barriers are suggested. These suggestions were provided to several export enterprises for their export strategy design. 展开更多
关键词 Technical Barriers to Trade two country model economic system modeling computer simulation strategy design
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Taiwan Solution:One Country,Two Systems
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作者 XUE LISHENG ZHANGJUAN 《China Today》 2000年第5期9-11,共3页
ZENG Jianhui, spokesman of the Third Session of the Ninth National People’s Congress (NPC), acknowledged on March 4 that the Taiwan Question was widely discussed at the Third Session of the Ninth NPC and the Ninth Ch... ZENG Jianhui, spokesman of the Third Session of the Ninth National People’s Congress (NPC), acknowledged on March 4 that the Taiwan Question was widely discussed at the Third Session of the Ninth NPC and the Ninth Chinese People’s Political Consultative Conference (CPPCC). Following the return of Hong Kong and Macao, the Taiwan Question has been becoming an increasingly closely watched process. 展开更多
关键词 taiwan Solution:One country Two Systems NPC US
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Exploring Taiwan’s China Landscape Painting Aesthetic Preferences Through Evaluation Grid Method and the Continuous Fuzzy Kano Model
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作者 Chin-Chin Kuo Jiann-Sheng Jiang Min-Min Lin 《Journal of Contemporary Educational Research》 2023年第12期268-276,共9页
The primary objective of this study is to apply the Evaluation Grid Method(EGM)and the continuous fuzzy Kano quality model to explore the cognitive preferences of Taiwan China residents regarding the beauty of Taiwan... The primary objective of this study is to apply the Evaluation Grid Method(EGM)and the continuous fuzzy Kano quality model to explore the cognitive preferences of Taiwan China residents regarding the beauty of Taiwan’s China landscape paintings.The aim is to contribute to the development of social and cultural art and promote the widespread appeal of art products.Through a literature review,consultations with aesthetic experts,and the application of Miryoku Engineering’s EGM,this paper consolidates the factors that contribute to the attractiveness of painting art products among Taiwan China residents,taking into account various aesthetic qualities.Simultaneously,the paper introduces the use of the triangular fuzzy golden ratio scale semantics,specifically the equal-ratio aesthetic scale semantics,as a replacement for the traditional subjective consciousness model.Departing from the traditional discrete Kano model that employs the mode as the standard for evaluating quality,this study applies triangular fuzzy numbers to the continuous Kano quality model to analyze the diverse preferences and evaluation standards of the public.The hope is that this research methodology will not only deepen Taiwan China residents’understanding and aesthetic literacy of painting art but also serve as a reference for the popularization of art products. 展开更多
关键词 Aesthetic literacy taiwan’s landscape painting Miryoku engineering Evaluation grid method(EGM) Fuzzy Kano model Golden ratio scale semantics
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Discourse Analysis of the Belt and Road Initiative From the Perspective of Central Asian Countries: A Case Study of the Republic of Kazakhstan
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作者 CHEN Jia LIU Shumin +1 位作者 FU Da’an SHAO Di 《Journalism and Mass Communication》 2024年第2期96-100,共5页
This study employs Norman Fairclough’s Critical Discourse Analysis(CDA)three-dimensional model,using the Republic of Kazakhstan as a case study,to delve into the discourse construction of China’s Belt and Road Initi... This study employs Norman Fairclough’s Critical Discourse Analysis(CDA)three-dimensional model,using the Republic of Kazakhstan as a case study,to delve into the discourse construction of China’s Belt and Road Initiative(BRI)in Central Asian countries.Through detailed analysis of policy documents,media reports,and public discussions in Central Asian countries,this paper reveals how the BRI constructs specific social practices,discourse events,and textual meanings within these nations.The findings indicate that through this global development strategy,China has not only strengthened its economic ties with Central Asian countries but has also exerted profound influences on political,cultural,and social levels. 展开更多
关键词 Belt and Road Initiative Central Asian countries discourse analysis Norman Fairclough’s three-dimensional model
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Numerical Study on Tides in the Taiwan Strait and its Adjacent Areas 被引量:3
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作者 朱佳 胡建宇 +4 位作者 张文舟 曾淦宁 陈德文 陈金泉 商少平 《Marine Science Bulletin》 CAS 2009年第2期23-36,共14页
Diurnal and semi-diurnal tides in the Taiwan Strait and its adjacent areas are calculated by using a two-dimensional finite-difference model. Compared with data of more than 20 observation stations around the Taiwan S... Diurnal and semi-diurnal tides in the Taiwan Strait and its adjacent areas are calculated by using a two-dimensional finite-difference model. Compared with data of more than 20 observation stations around the Taiwan Strait, the model-produced results agree quite well with those of previous researches using observational data from coastal tidal gauge stations. According to the results, the co-tidal and co-range charts are given. Furthermore, the characteristics of 8 major tidal constituents have been uminated respectively. The result shows that: (1) The tide motion can be attributed to the interaction between the degenerative rotary tidal system in the north and the progressive tidal system in the south. (2) The southward and northward tidal waves of semi-diurnal tide converge in the middle of the Taiwan Strait while the diurnal tidal waves propagate southwestward through the Taiwan Strait and the Luzon Strait. (3) The maximum amplitude of semi-diurnal tides exists at the area between the Meizhou Bay and Xinghua Bay, and that of diurnal tides appears in the region to the east of the Leizhou Peninsula, (4) The patterns of co-tidal and co-range charts of N2, K2 and P1, Q1 tidal constituents are similar to those of M2, S2 and K1 O1 tidat constituents, respectively 展开更多
关键词 taiwan Strait and its adjacent areas tidal characteristics model
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“一带一路”倡议下实用新型制度的国际协调
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作者 管荣齐 赵旖鑫 《科技与法律(中英文)》 2025年第1期91-102,共12页
“一带一路”倡议提出以来已逾十载,我国在这一过程中逐渐具备了规则创新的能力与契机,该种创新可由缺乏国际协调的实用新型制度先行。“一带一路”共建国家以及沿线区域性知识产权组织存在实用新型制度本土化的立法基础、改革经验及协... “一带一路”倡议提出以来已逾十载,我国在这一过程中逐渐具备了规则创新的能力与契机,该种创新可由缺乏国际协调的实用新型制度先行。“一带一路”共建国家以及沿线区域性知识产权组织存在实用新型制度本土化的立法基础、改革经验及协调实践,考虑实用新型制度在保护渐进式创新、维护共建发展中国家利益、提升知识产权国际博弈话语权等方面所发挥的作用,我国应当推行从软法到硬法的实用新型国际协调行动。包括但非限于借助“一带一路”国际合作高峰论坛发起协调倡议、倡导由世界知识产权组织出台《实用新型示范法》、借鉴欧盟的开放协调机制进行规则协商等,并将实用新型制度引入更多双边、多边贸易协定谈判场景。 展开更多
关键词 “一带一路” 实用新型 渐进式创新 国际协调 发展中国家
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基于ISM-24Model的重大铁路事故组织致因研究 被引量:14
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作者 左博睿 帅斌 黄文成 《中国安全科学学报》 CAS CSCD 北大核心 2020年第10期47-54,共8页
为探究重大铁路事故深度组织致因机制,结合24Model与解释结构模型(ISM),构建ISM-24Model事故深度组织致因分析框架。首先,基于24Model致因识别程序识别个人及组织因素,然后结合集成决策实验室分析法(DEMATEL)与ISM法构建深度组织致因综... 为探究重大铁路事故深度组织致因机制,结合24Model与解释结构模型(ISM),构建ISM-24Model事故深度组织致因分析框架。首先,基于24Model致因识别程序识别个人及组织因素,然后结合集成决策实验室分析法(DEMATEL)与ISM法构建深度组织致因综合影响矩阵,计算其可达矩阵并最终获取组织因素间的相对重要程度及递阶结构。以台铁"10·21"事故为例进行实证研究,框架共识别出不安全的个人因素31项,组织因素14项。组织因素影响关系及递阶结构的分析结果表明:对安全投入认识不足是导致该事故发生的组织核心因素,而安全培训制度为受到不良影响最集中的组织因素;采取多元化措施整改缺失的组织因素可从根源上避免事故的再次发生;ISM-24Model可有效探讨事故中的深度组织致因作用规律,是24Model的有益补充。 展开更多
关键词 解释结构模型(ISM) 24model 重大铁路事故 深度组织致因 决策实验室分析法(DEMATEL) 台铁“10·21”事故
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Dengue outbreaks in Taiwan, 1998-2017: Importation, serotype and temporal pattern 被引量:1
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作者 Ying-Hen Hsieh 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2018年第8期460-466,共7页
Objective: To ascertain the role of imported cases and serotypes on dengue outbreaks in Taiwan which have been sporadic yet highly volatile during the past two decades, exhibiting record-breaking magnitude in recent y... Objective: To ascertain the role of imported cases and serotypes on dengue outbreaks in Taiwan which have been sporadic yet highly volatile during the past two decades, exhibiting record-breaking magnitude in recent years. Methods: Confirmed case and serotype data from Taiwan Centers for Disease Control during 1998-2017 were fully examined, with fitting of weekly and daily case data of each city/county to a mathematical model to pinpoint the waves of cases and their locations. Moreover, we quantify the timing of turning point and transmission potential of each wave and determine its circulating serotype, to ascertain any pattern or connection between the variations in circulating serotypes and the magnitude/transmissibility of outbreak. Results: While the number of imported case increased steadily during past two decades, the yearly number of indigenous cases fluctuated wildly. Moreover, while yearly percentages of serotypes for imported cases remains steady, that of indigenous cases does not exhibit any clear pattern. There was at least one wave of reported cases somewhere in Taiwan every year from 1998 to 2015, except in 2016-2017. The effective reproduction number R for all waves in all locations ranged from 1.14 to 2.87, with the exception of two Tainan waves, in 2010(3.95) and 2015(6.84). Four major outbreaks of over 2000 cases reveal circulation of one dominant serotype. Conclusions: Correlation between imported cases and indigenous outbreak prove to be difficult to ascertain, even with the availability of serotype data. However, although there had been occasional co-circulation of serotypes in one location, and for some years with different serotypes circulating in different locations, all major outbreaks of over 2 000 cases during the past two decades are due to circulation of mainly a single serotype, perhaps indicating greater transmission potential with one dominating serotype. 展开更多
关键词 DENV SEROTYPE taiwan Imported cases Mathematical model Reproduction number
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Volume transport in the East Taiwan Channel in response to diff erent tracks of typhoons as revealed by HYCOM data 被引量:1
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作者 Yuanshou HE Po HU +2 位作者 Bing YANG Yuqi YIN Yijun HOU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第1期22-36,共15页
Northward infl ow through the East Taiwan Channel is vital in modulation of water exchange processes off northeastern Taiwan,China.In addition to the eff ects of the Kuroshio Current and westward-propagating oceanic m... Northward infl ow through the East Taiwan Channel is vital in modulation of water exchange processes off northeastern Taiwan,China.In addition to the eff ects of the Kuroshio Current and westward-propagating oceanic mesoscale eddies,the seas off eastern Taiwan,China,are frequently infl uenced by typhoons.Focusing on extrema of East Taiwan Channel volume transport(ETCVT)that appear within days of typhoon infl uence,this study investigated 124 historical cyclones including 91 typhoons that passed over the study sea area off eastern Taiwan,China.Based on 25-year HYbrid Coordinate Ocean Model(HYCOM)data,71%of short-term(within 10 d)ETCVT absolute values with>5 Sv occurred under the infl uence of typhoons crossing the study sea area,and the maximum short-term ETCVT extrema induced by typhoons were 12.5 and-10.9 Sv.The ETCVT extrema induced by typhoons showed reasonable positive correlation with typhoon wind speed.More importantly,the ETCVT extrema diff ered in response to diff erent typhoon tracks.Three types of typhoon were identifi ed based on their track and impact on ETCVT.Representative typhoon cases were examined to elucidate the specifi cs of each typical response.Based on historical best track data and HYCOM data,it was established that Type I typhoons caused the ETCVT to exhibit a negative extremum followed by a positive extremum.All Type I,II,and III typhoons tended to result in typical ETCVT fl uctuations in the surface mixing layer above the depth of 50-100 m,while Type II typhoons were more likely to induce ETCVT fl uctuations in the subsurface layer.The fi ndings of this study enhance understanding of ETCVT extrema that occur following typhoon passage,which is valuable for short-term physical-biogeochemical studies both in the study region and in areas downstream owing to the large net volume transport changes induced by typhoons. 展开更多
关键词 ocean modeling East taiwan Channel volume transport extrema TYPHOON
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Comparative Study of Volatility Forecasting Models: The Case of Malaysia, Indonesia, Hong Kong and Japan Stock Markets 被引量:1
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《Economics World》 2017年第4期299-310,共12页
This paper aims to investigate the effectiveness of four volatility forecasting models, i.e. Exponential Weighted Moving Average (EWMA), Autoregressive Integrated Moving Average (ARIMA) and Generalized Auto-Regres... This paper aims to investigate the effectiveness of four volatility forecasting models, i.e. Exponential Weighted Moving Average (EWMA), Autoregressive Integrated Moving Average (ARIMA) and Generalized Auto-Regressive Conditional Heteroscedastic (GARCH), in four stock markets Indonesia, Malaysia, Japan and Hong Kong. Using monthly closing stock index prices collected from 1 st January 1998 to 31 st December 2015 for the four selected countries, results obtained confirm that volatility in developed markets is not necessarily always lower than the volatility in emerging markets. Among all the three models, GARCH (1, l) model is found to be the best forecasting model for stock markets in Malaysia, Indonesia, and Japan, while EWMA model is found to be the best forecasting model for Hong Kong stock market. The outperformance of GARCH (1, 1) found supports again what is found in Minkah (2007). 展开更多
关键词 volatility forecasting models GARCH (1 1) EWMA ARIMA effectiveness emerging countries
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An Approach of Reducing Overall Level of Export Fluctuations of the Export-oriented Countries 被引量:1
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作者 Huiwen Ma Yiming Cai 《Journal of Economic Science Research》 2020年第3期30-35,共6页
Overall level of export fluctuations of the export-oriented countries with rising export volume partly stem from the market failure caused by free choice of export enterprises,some government intervention thus may be ... Overall level of export fluctuations of the export-oriented countries with rising export volume partly stem from the market failure caused by free choice of export enterprises,some government intervention thus may be necessary.To reduce the level of fluctuations of the export growth rates in these countries,this paper,taking the significant differences of the exports among various markets into account and thus using a new index named relative variance to measure the export volatility risks,proposes a model of merchandise market portfolio,a modified version of Markowitz model,available to provide explicit guidelines for the firms,the industries and even the whole country to optimize the structure of their export markets.An application of this model to the case of China’s apple is then discussed.The results show that the market share of China’s apple in 7 sub-markets should be redistributed drastically. 展开更多
关键词 Export-oriented country Relative variance Markowitz model Export market portfolio model
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Quantitative estimation of land surface evapotranspiration in Taiwan based on MODIS data
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作者 Che-sheng ZHAN Jie ZHAO +1 位作者 Hui-xiao WANG Jian YIN 《Water Science and Engineering》 EI CAS 2011年第3期237-245,共9页
Land surface evapotranspiration (ET) determines the local and regional water-heat balances. Accurate estimation of regional surface ET provides a scientific basis for the formulation and implementation of water cons... Land surface evapotranspiration (ET) determines the local and regional water-heat balances. Accurate estimation of regional surface ET provides a scientific basis for the formulation and implementation of water conservation programs. This study set up a table of the momentum roughness length and zero-plane displacement related with land cover and an empirical relationship between land surface temperature and air temperature. A revised quantitative remote sensing ET model, the SEBS-Taiwan model, was developed. Based on Moderate Resolution Imaging Spectroradiometer (MODIS) data, SEBS-Taiwan was used to simulate and evaluate the typical actual daily ET values in different seasons of 2002 and 2003 in Taiwan. SEBS-Taiwan generally performed well and could accurately simulate the actual daily ET. The simulated daily ET values matched the observed values satisfactorily. The results indicate that the net regional solar radiation, evaporation ratio, and surface ET values for the whole area of Taiwan are larger in summer than in spring, and larger in autumn than in winter. The results also show that the regional average daily ET values of 2002 are a little higher than those of 2003. Through analysis of the ET values from different types of land cover, we found that forest has the largest ET value, while water areas, bare land, and urban areas have the lowest ET values. Generally, the Northern Taiwan Region, including llan County, Nantou County, and Hualien County, has higher ET values, while other cities, such as Chiayi, Taichung, and Tainan, have lower ET values. 展开更多
关键词 EVAPOTRANSPIRATION quantitative remote sensing MODIS SEBS model taiwan
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Study on Sesame Export for Sudan Based on Gravity Model
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作者 Mansour Yousif Ahmed Adam Shiwei Xu +2 位作者 Wen Yu Shengwei Wang Siek Darith 《World Journal of Engineering and Technology》 2017年第2期31-39,共9页
This study aimed to investigate the effect of social and economic differences between importer and exporter countries on trade flows of Sesame seed product. The analysis was carried out by estimating the gravity model... This study aimed to investigate the effect of social and economic differences between importer and exporter countries on trade flows of Sesame seed product. The analysis was carried out by estimating the gravity model. The sample covered a total of 14 countries for the period from 1997 to 2009. The results showed that the social and economic differences between countries have a significant and positive or negative effect on Sesame seeds trade. Furthermore, we found that the same language, distance and sesame production in export country have positive effect for the sesame export from Sudan. 展开更多
关键词 SESAME TRADE Gravity model SUDAN PARTNER COUNTRIES Policy
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Optimization of Urban Rail Transportation in Emerging Countries Using Operational Research Techniques
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作者 M. C. Agarana T. A. Anake H. I. Okagbue 《Applied Mathematics》 2016年第10期1116-1123,共8页
Rail systems are gradually becoming the most desirable form of transit infrastructure around the world, partly because they are becoming more environmentally friendly compared with airplanes and automobiles. This pape... Rail systems are gradually becoming the most desirable form of transit infrastructure around the world, partly because they are becoming more environmentally friendly compared with airplanes and automobiles. This paper examines the place of emerging countries in this move of implementing modern rail system that will eventually enhance the realization of a low-carbon society. Network model, transportation model and linear programming algorithms are used to model the present urban rail transport system in Nigeria, as an emerging country, in order to optimize it. Operational research methods, including simplex method and MODI, with the aids of computer software (excel solver and LIP solver) were adopted to solve the resulting models. The results showed that optimization of rail transport system will not only reduce carbon emission but also bring about economic development which is required for the eradication of prevalent poverty in these emerging countries. 展开更多
关键词 Rail System Emerging Countries Operational Research Network model Transportation model Linear Programming Algorithm
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