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Impact of COVID-19 on College Students’Non-intellectual Factors and Corresponding Countermeasures
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作者 HE Tong-tong HU Xin-yun +1 位作者 JIANG Dan ZHANG Shun-sheng 《Journal of Literature and Art Studies》 2023年第2期110-116,共7页
The outbreak of COVID-19 in December 2019 has exerted a wide and everlasting impact on the world,which has also influenced education enormously.The adjustment of objective learning environment during the COVID-19 pand... The outbreak of COVID-19 in December 2019 has exerted a wide and everlasting impact on the world,which has also influenced education enormously.The adjustment of objective learning environment during the COVID-19 pandemic makes the influence of non-intellectual factors on college students worthy of investigation,research and analysis.Based on this,we have launched a questionnaire survey on 500 college students who have witnessed the pandemic,and referred to related literature,network documents,news reports,contrast and analysis of college students’non-intelligence factors before and after the outbreak of the different levels of change,summing up some new measures to promote the development of college students’non-intelligence factors under the COVID-19 outbreak for online learning and autonomous learning. 展开更多
关键词 COVID-19 college students’non-intellectual factors impact learning enlightenment
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A novel approach to the dynamic response analysis of Euler-Bernoulli beams resting on a Winkler soil model and subjected to impact loads
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作者 Adolfo Foriero Filippo Santucci de Magistris Giovanni Fabbrocino 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第2期389-401,共13页
This work presents a novel approach to the dynamic response analysis of a Euler-Bernoulli beam resting on a Winkler soil model and subjected to an impact loading.The approach considers that damping has much less impor... This work presents a novel approach to the dynamic response analysis of a Euler-Bernoulli beam resting on a Winkler soil model and subjected to an impact loading.The approach considers that damping has much less importance in controlling the maximum response to impulsive loadings because the maximum response is reached in a very short time,before the damping forces can dissipate a significant portion of the energy input into the system.The development of two sine series solutions,relating to different types of impulsive loadings,one involving a single concentrated force and the other a distributed line load,are presented.This study revealed that when a simply supported Euler-Bernoulli beam,resting on a Winkler soil model,is subject to an impact load,the resulting vertical displacements,bending moments and shear forces produced along the span of the beam are considerably affected.In particular,the quantification of this effect is best observed,relative to the corresponding static solution,via an amplification factor.The computed impact amplification factors,for the sub-grade moduli used in this study,were in magnitude greater than 2,thus confirming the multiple-degree-of-freedom nature of the problem. 展开更多
关键词 beam-Winkler-soil model sub-grade moduli impact load impact distributed line load dynamic solution impact amplification factor
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Impacting Factors of Elemental Mercury Re-emission across a Lab-scale Simulated Scrubber 被引量:11
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作者 武成利 曹晏 +1 位作者 董众兵 潘伟平 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第3期523-528,共6页
Elemental mercury(Hg0)re-emissions from slurries and solutions were evaluated in a lab-scale simulated scrubber.Oxidized mercury(Hg2 +)standard solution was injected into the simulated scrubber at a desired rate to si... Elemental mercury(Hg0)re-emissions from slurries and solutions were evaluated in a lab-scale simulated scrubber.Oxidized mercury(Hg2 +)standard solution was injected into the simulated scrubber at a desired rate to simulate absorbing and dissolving of Hg2 +in the flue gas across wet flue gas desulfurization(WFGD)systems. PS analytical mercury analyzer was used to continuously determine Hg0re-emission concentrations in the carrier gas from the scrubber.Sulfite ion in the slurry of CaSO3 was validated to reduce Hg 2+to Hg 0,while no Hg 0 re-emission occurred from slurries of CaSO4 and CaO.Transitional metal ions with low chemical valence such as Fe2 +,Pb 2+,Ni 2+, 2 AsO-and Cu +were used to prepare solutions with concentration levels of mmol·L-1.Reduction reaction of Hg2 +to Hg 0was observed from these solutions.Reduction capabilities for the different transitional metal ions in the solutions were:Pb2 +>Cu +>Fe 2+> 2 AsO->Ni 2+. 展开更多
关键词 汞分析仪 实验室规模 排放因子 洗涤器 模拟 元素 湿法烟气脱硫 过渡金属离子
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Dynamic Response Impact of Vehicle Braking on Simply Supported Beam Bridges with Corrugated Steel Webs Based on Vehicle-Bridge Coupled Vibration Analysis
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作者 Yan Wang Siwen Li Na Wei 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期3467-3493,共27页
A novel approach for analyzing coupled vibrations between vehicles and bridges is presented,taking into account spatiotemporal effects and mechanical phenomena resulting fromvehicle braking.Efficient modeling and solu... A novel approach for analyzing coupled vibrations between vehicles and bridges is presented,taking into account spatiotemporal effects and mechanical phenomena resulting fromvehicle braking.Efficient modeling and solution of bridge vibrations induced by vehicle deceleration are realized using this method.The method’s validity and reliability are substantiated through numerical examples.A simply supported beam bridge with a corrugated steel web is taken as an example and the effects of parameters such as the initial vehicle speed,braking acceleration,braking location,and road surface roughness on the mid-span displacement and impact factor of the bridge are analyzed.The results show that vehicle braking significantly amplifies mid-span displacement and impact factor responses in comparison to uniform vehicular motion across the bridge.Notably,the influence of wheelto-bridge friction forces is of particular significance and cannot be overlooked.When the vehicle initiates braking near the middle of the span,both the mid-span displacement and impact factor of the bridge exhibit substantial increases,further escalating with higher braking acceleration.Under favorable road surface conditions,the midspan displacement and the impact factor during vehicle braking may exceed the design values stipulated by codes.It is important to note that road surface roughness exerts a more pronounced effect on the impact factor of the bridge in comparison to the effects of vehicle braking. 展开更多
关键词 Corrugated steel web girder bridges simply supported beam bridges vehicle-bridge coupled vibration BRAKING impact factor
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Soil Phosphorus Release to the Water Bodies in the Upland Fields of Yellow Soil Areas and Impacting Factor
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作者 LIU Fang LUO Hai-bo +3 位作者 SU Yin-ge LIU Yuan-sheng HE Teng-bin LONG Jian 《Agricultural Sciences in China》 CAS CSCD 2005年第12期916-923,共8页
Soil phosphorus release to the water bodies in the upland fields of yellow soil areas and impacting factor was studied in Guizhou province. The results showed that the content of dissolved active P of surface runoff f... Soil phosphorus release to the water bodies in the upland fields of yellow soil areas and impacting factor was studied in Guizhou province. The results showed that the content of dissolved active P of surface runoff from various upland fields of yellow-soil were significantly different, which the concentrations of dissolved active P of runoff correlated with the contents of available-P, amorphous oxides of A1, and organic matter in the soils. The amount of soil phosphorus release to the water bodies affected by the level of applying P fertilizer and the process of corn growth, which with fertilizing from 150 to 900 kg P205 ha^-1 in the soil with high P level, the average contents of dissolved active P in the permeability-water of the soil increased from 0.020 mg L^-1 to 0.137 mg L^-1. The amount of soil phosphorus release to the water bodies also affected by environmental factor, which the amount of soil phosphorus release significantly increased under the conditions that temperature is 30℃-35℃, water/soil ratios is 15:1-25:1, submergence-time by water is 12-18 h and pH value of acid rains is 3.82-3.73. 展开更多
关键词 Upland fields of yellow soil Soil F release Dissolved active P of runoff impacting factor
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A Comparative Analysis of Chemical Properties and Factors Impacting Spring Sea Fog over the Northwestern South China Sea
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作者 韩利国 徐峰 +3 位作者 徐建军 李雅洁 柴博语 吕晶晶 《Journal of Tropical Meteorology》 SCIE 2022年第3期297-307,共11页
In the present study,we analyzed the chemical properties and factors impacting the sea fog water during two sea fog events over the northwestern South China Sea in March 2017,and compared our results with those of oth... In the present study,we analyzed the chemical properties and factors impacting the sea fog water during two sea fog events over the northwestern South China Sea in March 2017,and compared our results with those of other regions.The sea fog water during these two events were highly acidic and their average pH was below 3,which was related to the high initial acidifying potential and large amounts of NOand SOnot involved in the neutralization reaction.The dominant cations in the sea fog water were Naand NH.The primary anions in the sea fog water over the South China Sea were Cland NO,while that over the North Pacific Ocean was mainly SO,and ratios of the three fog water ions near the Donghai Island were similar.Ions in the sea fog water during the two events were mainly derived from marine aerosols,while the difference was that the first low-level sea fog airflow trajectory passed over Hainan Island.Therefore,the proportion of K+in the first sea fog was much higher than that in sea water and the second.Sulfate was the key to fog water nucleation,which made ion concentration in the sea fog water during the second event higher than that during the first.A decrease in average diameter during the first sea fog formation led to an ion concentration increase,while the average diameter of sea fog water during the second event was lower than that during the first,which corresponded with a moderate ion concentration increase. 展开更多
关键词 northwestern South China Sea sea surface fog chemical properties impact factors
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Factors Impacting Teacher Stress and Mitigation of This Stress in UK School System
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作者 Jiayu Zhou Yajing Xue 《Review of Educational Theory》 2022年第1期10-15,共6页
Teacher plays an essential role in the lives of children.In addition to promoting their learning and improving academic performance,teachers have a major character in developing student’s creative potential and growi... Teacher plays an essential role in the lives of children.In addition to promoting their learning and improving academic performance,teachers have a major character in developing student’s creative potential and growing into responsible citizens.However,in recent years,a report by National Foundation for Educational(2019)claimed that the teacher has faced many challenges than other occupations.Stress is one of the most challenges for the teacher to overcome.The main sources of teacher stress generally come from personal,interpersonal as well as organization.This essay explores and discusses the factors that impact or affect teacher stress,exploring the theories and concepts associated with teacher stress and mitigation practices for teacher stress in the United Kingdom school system-from primary and secondary school. 展开更多
关键词 Teacher pressure Stress mitigation impact factor
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Impact factors identification of spatial heterogeneity of herbaceous plant diversity on five southern islands of Miaodao Archipelago in North China 被引量:8
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作者 池源 石洪华 +3 位作者 王晓丽 覃雪波 郑伟 彭士涛 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第5期937-951,共15页
Herbaceous plants are widely distributed on islands and where they exhibit spatial heterogeneity.Accurately identifying the impact factors that drive spatial heterogeneity can reveal typical island biodiversity patter... Herbaceous plants are widely distributed on islands and where they exhibit spatial heterogeneity.Accurately identifying the impact factors that drive spatial heterogeneity can reveal typical island biodiversity patterns.Five southern islands in the Miaodao Archipelago,North China were studied herein.The spatial distribution of herbaceous plant diversity on these islands was analyzed,and the impact factors and their degree of impact on spatial heterogeneity were identified using CCA ordination and ANOVA.The results reveal 114 herbaceous plant species,belonging to 94 genera from 34 families in the50 plots sampled.The total species numbers on different islands were significantly positively correlated with island area,and the average a diversity was correlated with human activities,while the(3 diversity among islands was more affected by island area than mutual distances.Spatial heterogeneity within islands indicated that the diversities were generally high in areas with higher altitude,slope,total nitrogen,total carbon,and canopy density,and lower moisture content,pH,total phosphorus,total potassium,and aspect.Among the environmental factors,pH,canopy density,total K,total P,moisture content,altitude,and slope had significant gross effects,but only canopy density exhibited a significant net effect.Terrain affected diversity by restricting plantation,plantation in turn influenced soil properties and the two together affected diversity.Therefore,plantation was ultimately the fundamental driving factor for spatial heterogeneity in herbaceous plant diversity on the five islands. 展开更多
关键词 Island ecology herbaceous plant biodiversity spatial heterogeneity impact factor identification PLANTATION
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Impact Factors of Energy Productivity in China: An Empirical Analysis 被引量:2
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作者 Wei Chu1,2, Shen Manhong2 1. College of Economics and Management, Zhejiang Sci-Tech University, Hangzhou Zhejiang 310018, China 2. College of Economics, Zhejiang University, Hangzhou Zhejiang 310017, China 《Chinese Journal of Population,Resources and Environment》 北大核心 2007年第2期28-33,共6页
This article developed a decomposition model of energy productivity on the basis of the economic growth model. Four factors were considered which may influence China’s energy productivity according to this model: tec... This article developed a decomposition model of energy productivity on the basis of the economic growth model. Four factors were considered which may influence China’s energy productivity according to this model: technology improvement, resource allocation structure, industrial structure and institute arrangement. Then, an econometric model was employed to test the four factors empirically on the basis of China’s statistical data from 1978 to 2004. Results indicated that capital deepening con- tributes the most (207%) to energy efficiency improvement, and impact from labor forces (13%) is the weakest one in resource factor; industrial structure (7%) and institute innovation (9.5%) positively improve the energy productivity. 展开更多
关键词 energy productivity impact factor economic growth China
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Bromate removal by activated carbon adsorption:material selection and impact factors study 被引量:2
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作者 刘彤冕 赵志伟 +3 位作者 崔福义 刘冬梅 王欢 朱琦 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第5期81-85,共5页
Studies are conducted by using activated carbon process aimed at bromate removal from the raw water.Screening of activated carbon for bromate removal was performed in different activated carbons.GAC Merck possesses th... Studies are conducted by using activated carbon process aimed at bromate removal from the raw water.Screening of activated carbon for bromate removal was performed in different activated carbons.GAC Merck possesses the highest iodine number and surface area,the highest number of basic groups and Vmeso,thereby contains the highest adsorption velocity and adsorption capacity.Impact factors of bromate removal on activated carbon were studied.Through static absorption experiments we studied the effect of adsorption time,pH,temperature,anions and organic matter on bromate removal.With the decrease of pH,removal of bromate enhanced,suggests that it may be possible to increase bromate reduction through pH control.The increase of temperature will be favorable to adsorption of bromate on activated carbon.Anions and organic matter can inhibit the adsorption of bromate on activated carbon through competing active sites.Bromate removal can be improved by controlling key water quality parameters. 展开更多
关键词 BROMATE activated carbon ADSORPTION impact factors
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Seasonal dynamics and impact factors of urban forest CO2 concentration in Harbin,China 被引量:2
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作者 Wenyu Zheng Yunwei Zhou +1 位作者 Han Gu Zhongping Tian 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第1期125-132,共8页
CO2 concentrations in different plant communities (larch, birch, lilac, and grassland) were measured during the growing season in the Heilongjiang Forest Botanical Garden to study diurnal variation, seasonal and ann... CO2 concentrations in different plant communities (larch, birch, lilac, and grassland) were measured during the growing season in the Heilongjiang Forest Botanical Garden to study diurnal variation, seasonal and annual dynamics and factors that impact CO2 concentration in different spaces. CO2 concentration in different communities in green lands had an obvious diurnal variation, chronically decreasing, and temperature influenced the lilac area and the grassland. Seasonally, CO2 was lowest in the larch green land (344.03 ±23.03 μmol/mol) and highest in the grassland (360.13 ± 22.43 μmol/mol). The overall trend in CO2 concentration was autumn 〉 spring 〉 summer; temperature is the main factor controlling variation in CO2 concentrations during the growing season; the CO2 concentration at the larch, birch, lilac, and grassland types of sites was negatively correlated with land surface temperature and air temperature, and the CO2 concentration at the larch and birch sites was positively correlated with atmospheric pressure. Without any obvious annual change law, further study and observation are needed. 展开更多
关键词 CO2 concentration Ecological benefits Green land impact factors Plant communities
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Characterization of Aquabacterium parvum sp. Strain B6 during Nitrate-Dependent Fe(Ⅱ) Oxidation Batch Cultivation with Various Impact Factors 被引量:2
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作者 Xiaoxin Zhang Ulrich Szewzyk Fang Ma 《Transactions of Tianjin University》 EI CAS 2017年第4期315-324,共10页
In order to assess the capacity of Aquabacterium parvum sp. strain B6 for nitrate-dependent Fe(Ⅱ) oxidation,batch cultivation was conducted, and its ability to oxidize Fe(Ⅱ) coupled to nitrate reduction in the prese... In order to assess the capacity of Aquabacterium parvum sp. strain B6 for nitrate-dependent Fe(Ⅱ) oxidation,batch cultivation was conducted, and its ability to oxidize Fe(Ⅱ) coupled to nitrate reduction in the presence of diverse organic substrates was studied. Meanwhile, the nitrate-removal rate of B6 with various impact factors was further optimized by the response surface methodology(RSM). The results show that strain B6 is capable of utilizing different organic compounds as substrates for nitrate reduction. Compared with yeast extract, B6 showed a greater potential of chemical oxygen demand(COD)degradation and cell proliferation with acetate and glucose mediums, respectively, while citrate was not beneficial for this process due to its low consumption rate. RSM analysis demonstrated that the maximum nitrate-reduction rate of 30.64% could be achieved with an initial pH of 7.4,incubation temperature of 25.0 °C, and carbon source concentration of 266.10 mg/L. 展开更多
关键词 Nitrate-dependent FE(II) OXIDATION NITRATE reduction impact factors Optimization Aquabacteria
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Evaluation of vertical impact factor coefficients for continuous and integral railway bridges under high-speed moving loads 被引量:3
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作者 Anand M.Gharad Ranjan S.Sonparote 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2021年第2期495-504,共10页
In the railway bridge analysis and design method,dynamic train loads are regarded as static loads enhanced by an impact factor(IF).The IF coefficients for various railway bridges have been reported as a function of sp... In the railway bridge analysis and design method,dynamic train loads are regarded as static loads enhanced by an impact factor(IF).The IF coefficients for various railway bridges have been reported as a function of span length or frequency of the bridges in Eurocode(2003).However,these IF coefficient values neglect the effects of very high speeds(>200 km/h)and soil-structure interaction(SSI).In this work,a comprehensive study to assess the impact factor coefficients of mid-span vertical displacements for continuous and integral railway bridges subjected to high-speed moving loads is reported.Three different configurations,each for the three-dimensional(3D)continuous and integral bridge,are considered.Also,single-track(1-T)and two-track(2-T)“real train”loading cases for both these bridge types are considered.Subsequently,finite element analysis of the full-scale 3D bridge models,to identify their IF values,considering the effects of SSI for three different soil conditions,is conducted.The IF values obtained from the study for both bridge types are comparable and are greater than the values recommended by Eurocode(2003).The results reveal that with a loss of soil stiffness,the IF value reduces;thus,it confirms the importance of SSI analysis. 展开更多
关键词 impact factor dynamic soil-structure interaction high-speed moving loads finite element analysis continuous bridge integral bridge
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Study on the Spreading of Environmental Impact of Human Being' s Activities and Its Crucial Factors in Upper Minjiang River 被引量:1
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作者 FanHong ZhaoHong-da 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03B期949-956,共8页
This paper focuses on the historical transition of human being's activities and the eco-environment in the upper reaches of Minjiang River. The history is divided into 4 periods, each with its own feature. During ... This paper focuses on the historical transition of human being's activities and the eco-environment in the upper reaches of Minjiang River. The history is divided into 4 periods, each with its own feature. During the period of nomad immigration, the top-line of the subalpine forest was forced downward by the expanding subalpine meadow. During the period of farming nationality immigration, the bottom-line of middle mountain forest had moved upward forced by the needs for land or timber of the increasing population in the valley basia During the period of the early exploiting, the focus resource was the timber. The total output was limited, comparing with the later period, because of the bad accessibility. But it was large enough to impact the forest ecosystem of the deforesting area. The recent 50 years is the crucial period of economic development and eco-environment degradation. This paper points out that the impact of human being's activities for environment lies on 3 factors: 1) physical features control the location and tendency eco-environmental change; 2) population and productivity control the scale and speed of eco-environmental change; 3) regional accessibility controls the time and location of eco-environmental change. 展开更多
关键词 historical period human being's activities environmental impact crucial factors
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Pore scale performance evaluation and impact factors in nitrogen huff-n-puff EOR for tight oil 被引量:2
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作者 Yi-Lei Song Zhao-Jie Song +4 位作者 Yun-Fei Zhang Ze-Hui Xie Li-Chao Zhang Dai-Gang Wang Gang Hui 《Petroleum Science》 SCIE CAS CSCD 2022年第6期2932-2940,共9页
Nitrogen huff-n-puff(N_(2)HnP) appears to be an economical and high-efficiency enhanced oil recovery(EOR) technique for tight oil reservoirs.There is however a lack of understanding of the pore-level EOR performance o... Nitrogen huff-n-puff(N_(2)HnP) appears to be an economical and high-efficiency enhanced oil recovery(EOR) technique for tight oil reservoirs.There is however a lack of understanding of the pore-level EOR performance of N2HnP under tight reservoir conditions.In this work,a non-magnetic reactor was created and combined with a nuclear magnetic resonance(NMR) device for real-time monitoring of oil distribution in the HnP experiment.N_(2)HnP experiments were then performed in a tight sandstone core sample at a temperature of 353 K and an injection pressure≥ 24 MPa.The pore-level oil distribution under reservoir conditions was monitored and the EOR performance of N2HnP in specific pores was analyzed.The pore throat structures of the core sample and the phase behavior of the N_(2)-Oil system were analyzed to elucidate the EOR mechanism of N_(2)HnP.An oil recovery factor of 37.52% can be achieved after four cycles,which proves the EOR potential of N_(2)HnP for tight reservoirs.The highest recoveries after N_(2)HnP are obtained in the large pores,followed by the medium pores,the small pores,and finally the micro pores.Increases in soaking time and injection pressure resulted in slight and pronounced increases in oil recovery,respectively,both of which are mainly reflected in the first cycle.Specifically,increasing the soaking time only slightly improves the cumulative oil recovery in the small pores while increasing the injection pressure significantly improves the cumulative oil recovery in the small,medium,and large pores simultaneously.However,variations in both injection pressure and soaking time have a negligible effect on the cumulative oil recovery of the micro pores. 展开更多
关键词 Tight oil reservoirs N_(2)huff-n-puff Pore-level production characteristics impact factors Nuclear magnetic resonance
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Physical, Psychological, and Social Health Impact of Temperature Rise Due to Urban Heat Island Phenomenon and Its Associated Factors 被引量:3
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作者 Li Ping WONG Haridah Alias +2 位作者 Nasrin Aghamohammadi Sima Aghazadeh Nik Meriam Nik Sulaiman 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第7期545-550,共6页
The Urban Heat Island Effect(UHI)has now become a commonly observed phenomenon worldwide.Indeed,it has become a significant environmental effect of urbanisation.In Malaysia,research results showed that UHI effects a... The Urban Heat Island Effect(UHI)has now become a commonly observed phenomenon worldwide.Indeed,it has become a significant environmental effect of urbanisation.In Malaysia,research results showed that UHI effects are very evident in several cities such as Kuala Lumpur and Putrajaya.UHI effect has long been observed to cause temperature of cities. 展开更多
关键词 AS UHI PSYCHOLOGICAL and Social Health impact of Temperature Rise Due to Urban Heat Island Phenomenon and Its Associated factors PHYSICAL
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Evaluating the impact and significance of meteorological factors upon dust storm occurrence 被引量:1
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作者 WanYuan Li ShiHua Lv +3 位作者 Ye Yu ZhiBao Dong ZhiBao Shen YuChun Chen 《Research in Cold and Arid Regions》 2011年第2期161-171,共11页
In this article, the quantitative impact and significance of factors on dust storm occurrence have been analyzed in detail, based on spring daily data sets of 17 meteorological factors and dust storm records during th... In this article, the quantitative impact and significance of factors on dust storm occurrence have been analyzed in detail, based on spring daily data sets of 17 meteorological factors and dust storm records during the period of 1954-2005 for 60 gauge stations distributed over Gansu Province of China. Results show that daily mean and maximum wind speeds and evaporation have a positive effect on dust storm occurrence, i.e., their increase can result in an increase of dust storm occurrence. Inversely, daily mean and minimum relative humidity, lowest surface air pressure, vapor pressure and number of sunny hours have a negative effect on dust storm occurrence. However, daily mean and highest surface air pressure; mean, highest and lowest surface air temperature; and precipitation of 20:00-08:00, 08:00-20:00 and 20:00-20:00 have a positive effect on dust storm occurrence in some places but negative in other places. On average, daily maximum and mean wind speeds, direction of the maximum wind, number of sunny hours and evaporation have a significant effect on dust storm occurrence in Gansu Province, but precipitation of 20:00--08:00, 08:00-20:00 and 20:00-20:00, and mean surface air pressure and temperature all have a minor influence upon dust storm occurrence. 展开更多
关键词 Gansu Province meteorological factor spring dust storm occurrence impact and significance
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Discipline Impact Factor: Some of Its History, Some of the Author's Experience of Its Application, the Continuing Reasons for Its Use and… Next Beyond 被引量:1
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作者 Vladimir S.Lazarev 《Journal of Data and Information Science》 CSCD 2020年第3期197-209,共13页
Purpose: This work aims to consider the role and some of the 42-year history of the discipline impact factor(DIF) in evaluation of serial publications. Also, the original "symmetric" indicator called the &qu... Purpose: This work aims to consider the role and some of the 42-year history of the discipline impact factor(DIF) in evaluation of serial publications. Also, the original "symmetric" indicator called the "discipline susceptibility factor" is to be presented. Design/methodology/approach: In accordance with the purpose of the work, the methods are analytical interpretation of the scientific literature related to this problem as well as speculative explanations. The information base of the research is bibliometric publications dealing with impact, impact factor, discipline impact factor, and discipline susceptibility factor.Findings: Examples of the DIF application and modification of the indicator are given. It is shown why research and university libraries need to use the DIF to evaluate serials in conditions of scarce funding for subscription to serial publications, even if open access is available. The role of the DIF for evaluating journals by authors of scientific papers when choosing a good and right journal for submitting a paper is also briefly discussed. An original indicator "symmetrical" to the DIF(the "discipline susceptibility factor") and its differences from the DIF in terms of content and purpose of evaluation are also briefly presented.Research limitations: The selection of publications for the information base of the research did not include those in which the DIF was only mentioned, used partially or not for its original purpose. Restrictions on the length of the article to be submitted in this special issue of the JDIS also caused exclusion even a number of completely relevant publications. Consideration of the DIF is not placed in the context of describing other derivatives from the Garfield impact factor. Practical implications: An underrated bibliometric indicator, viz. the discipline impact factor is being promoted for the practical application. An original indicator "symmetrical" to DIF has been proposed in order of searching serial publications representing the external research fields that might fit for potential applications of the results of scientific activities obtained within the framework of the specific research field represented by the cited specialized journals. Both can be useful in research and university libraries in their endeavors to improve scientific information services. Also, both can be used for evaluating journals by authors of scientific papers when choosing a journal to submit a paper.Originality/value: The article substantiates the need to evaluate scientific serial publications in library activities—even in conditions of access to huge and convenient databases(subscription packages) and open access to a large number of serial publications. It gives a mini-survey of the history of one of the methods of such evaluation, and offers an original method for evaluating scientific serial publications. 展开更多
关键词 Discipline impact factor Discipline susceptibility factor Citation analysis Journals evaluation Serials evaluation Information service
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Dynamic Impact Factor Induced by Idling Vehicle-Bridge Coupling Vibration 被引量:1
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作者 Lang Liu Jie Wang Hong Yang 《Journal of Harbin Institute of Technology(New Series)》 CAS 2022年第3期79-87,共9页
To analyze the impact effect induced by vehicle-bridge coupling vibration during traffic congesting, hundreds and thousands of congestion scenarios consisting of various vehicle platoons were collected and used to dev... To analyze the impact effect induced by vehicle-bridge coupling vibration during traffic congesting, hundreds and thousands of congestion scenarios consisting of various vehicle platoons were collected and used to develop vehicle models as well as traffic congestion load models. Furthermore, the idling vehicle-bridge coupling model was established by the finite element method and the congestion models were applied to calculate dynamic impact factors. Compared with the value specified in Chinese codes, the calculated values were 1.15-2.67 times as large as the latter, which indicates the impact factors caused by idling vehicle-bridge coupling under congestion situations were much larger than those in normal traffic conditions. As a result, a calibration factor of 1.7 was recommended for bridge design or evaluation when considering vehicle-bridge coupling vibration under heavy traffic congestion. The proposed analytical model, analysis method, and results could also be beneficial references to further investigation in this field. 展开更多
关键词 dynamic impact factor vehicle-bridge interaction traffic congestion code provisions
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Calculation of Ecological Footprint Based on Modified Method and Quantitative Analysis of Its Impact Factors——A Case Study of Shanghai 被引量:4
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作者 GAO Chengkang JIANG Dahe +1 位作者 WANG Dan YAN Jonathan 《Chinese Geographical Science》 SCIE CSCD 2006年第4期306-313,共8页
Ecological footprint(EF) has attracted much attention internationally as a potential indicator for sustainable development.In China,EF has also gained recognition in related fields and disciplines.Moreover,some schola... Ecological footprint(EF) has attracted much attention internationally as a potential indicator for sustainable development.In China,EF has also gained recognition in related fields and disciplines.Moreover,some scholars in these fields have proposed alternative methods to calculate EF and have made some progress.This paper,therefore,begins with the introduction and development of EF in China.However,the established methods of EF calculation hold some limitations,such as indicator variance and result abnormality.In order to resolve those problems,the authors make a further modification considering the demand of EF as a comprehensive indicator:1) More accurate analysis has been done to divide EF into several parts:imported EF,exported EF,and producible EF,which is the solution to the problem of abnormality in original EF results and can explain abnormal phenomena reasonably.2) Considering the actual situa-tion of Shanghai,amended equivalence factor is brought forward and a matrix is formed with equivalence factors.The measure can reduce the deviation between the fact and the results.3) The calculation compares local yield with global average yield to analyze the effects of yields.And based on local yields in different years,the results are more accurate.Finally,the calculation method is applied to calculating EF of Shanghai from 1980 to 2003,and the subsequent detailed analysis is presented.Available data and results suggest a statistically significant correlation coefficient between EF and GDP,population density and urbanization level.Through analyzing the process of calculating EF and its results,it can be seen that EF,as a macro-indicator,can not exactly indicate whether development within a region can meet the re-quests of sustainable development,which can be explained by the fact that the result of EF is impacted greatly by sub-jective factors including national policy,available technology,population,etc.Nevertheless,EF can demonstrate,at least to some degree,the regional status in terms of resources and energy consumption,as well as developmental potential.The calculation of EF,therefore,deserves further research to achieve more far-reaching significance in application. 展开更多
关键词 上海 生态足迹法 计算方法 定量分析 冲击因子 可持续发展
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