With the implementation of the Belt and Road Initiative, China is deepening its cooperation in oil and gas resources with countries along the Initiative. In order to better mitigate risks and enhance the safety of inv...With the implementation of the Belt and Road Initiative, China is deepening its cooperation in oil and gas resources with countries along the Initiative. In order to better mitigate risks and enhance the safety of investments, it is of significant importance to research the oil and gas investment environment in these countries for China's overseas investment macro-layout. This paper proposes an indicator system including 27 indicators from 6 dimensions. On this basis, game theory models combined with global entropy method and analytic hierarchy process are applied to determine the combined weights, and the TOPSIS-GRA model is utilized to assess the risks of oil and gas investment in 76 countries along the Initiative from 2014 to 2021. Finally, the GM(1,1) model is employed to predict risk values for 2022-2025. In conclusion, oil and gas resources and political factors have the greatest impact on investment environment risk, and 12 countries with greater investment potential are selected through cluster analysis in conjunction with the predicted results. The research findings may provide scientific decisionmaking recommendations for the Chinese government and oil enterprises to strengthen oil and gas investment cooperation with countries along the Belt and Road Initiative.展开更多
Background: Nigeria, a nation grappling with rapid population growth, economic intricacies, and complex healthcare challenges, particularly in Lagos State, the economic hub and most populous state, faces the challenge...Background: Nigeria, a nation grappling with rapid population growth, economic intricacies, and complex healthcare challenges, particularly in Lagos State, the economic hub and most populous state, faces the challenge of ensuring quality healthcare access. The overview of the effect of quality improvement initiatives in this paper focuses on private healthcare providers in Lagos State, Nigeria. The study assesses the impact of donor-funded quality improvement projects on these private healthcare facilities. It explores the level of participation, perceived support, and tangible effects of the initiatives on healthcare delivery within private healthcare facilities. It also examines how these initiatives influence patient inflow and facility ratings, and bring about additional benefits and improvements, provides insights into the challenges faced by private healthcare providers in implementing quality improvement projects and elicits recommendations for improving the effectiveness of such initiatives. Methods: Qualitative research design was employed for in-depth exploration, utilizing semi-structured interviews. Private healthcare providers in Lagos involved in the SP4FP Quality Improvement Project were purposively sampled for diversity. Face-to-face interviews elicited insights into participation, perceived support, and project effects. Questions covered participation levels, support perception, changes observed, challenges faced, and recommendations. Thematic analysis identified recurring themes from interview transcripts. Adherence to ethical guidelines ensured participant confidentiality and informed consent. Results: Respondents affirmed active involvement in the SP4FP Quality Improvement Project, echoing literature emphasizing private-sector collaboration with the public sector. While acknowledging positive influences on facility ratings, respondents highlighted challenges within the broader Nigerian healthcare landscape affecting patient numbers. Respondents cited tangible improvements, particularly in staff management and patient care processes, validating the positive influence of quality improvement projects. Financial constraints emerged as a significant challenge, aligning with existing literature emphasizing the pragmatic difficulties faced by private healthcare providers. Conclusions: This study illuminates the complex landscape of private healthcare provision in Lagos State, emphasizing the positive impact of donor-funded quality improvement projects. The findings provide nuanced insights, guiding policymakers, healthcare managers, and practitioners toward collaborative, sustainable improvements. As Nigeria progresses, these lessons will be crucial in shaping healthcare policies prioritizing population well-being.展开更多
[Objectives]To explore innovative strategies for rural agricultural economic development in the context of the Belt and Road Initiative.[Methods]This research adopts the method of literature review and field research,...[Objectives]To explore innovative strategies for rural agricultural economic development in the context of the Belt and Road Initiative.[Methods]This research adopts the method of literature review and field research,systematically combs the research results related to the Belt and Road Initiative and rural agricultural economic management,and deeply understands the actual situation of rural agricultural economic management.[Results]The research shows that in the context of the Belt and Road Initiative,the rural agricultural economy is facing new development opportunities and challenges,but there are also some problems.In the new period,we should accelerate the innovative development of rural agricultural economy by promoting market-oriented reform,strengthening scientific and technological innovation,optimizing the industrial structure,deepening international cooperation and other measures.The Belt and Road Initiative provides an important opportunity for the innovation of rural agricultural economic management.Rural agricultural economic management should be actively integrated into the Belt and Road construction to improve the level of rural agricultural economic management.[Conclusions]This study provides useful exploration and reference for the innovation of rural agricultural economic management models,which helps to promote the healthy development of rural agricultural economy and achieve the goal of rural revitalization.展开更多
BACKGROUND Colorectal cancer(CRC)plays a significant role in morbidity,mortality,and economic cost in the Belt and Road Initiative(“B and R”)countries.In addition,these countries have a substantial consumption of pr...BACKGROUND Colorectal cancer(CRC)plays a significant role in morbidity,mortality,and economic cost in the Belt and Road Initiative(“B and R”)countries.In addition,these countries have a substantial consumption of processed meat.However,the burden and trend of CRC in relation to the consumption of a diet high in processed meat(DHPM-CRC)in these“B and R”countries remain unknown.AIM To analyze the burden and trend of DHPM-CRC in the“B and R”countries from 1990 to 2019.METHODS We used the 2019 Global Burden of Disease Study to collate information regarding the burden of DHPM-CRC.Numbers and age-standardized rates(ASRs)of deaths along with the disability-adjusted life years(DALYs)were determined among the“B and R”countries in 1990 and 2019.Using joinpoint regression analysis,the average annual percent change(AAPC)was used to analyze the temporal trends of age-standardized DALYs rate(ASDALR)from 1990 to 2019 and in the final decade(2010–2019).RESULTS We found geographical differences in the burden of DHPM-CRC among“B and R”countries,with the three highest-ranking countries being the Russian Federation,China,and Ukraine in 1990,and China,the Russian Federation,and Poland in 2019.The burden of DHPM-CRC generally increased in most member countries from 1990 to 2019(all P<0.05).The absolute number of deaths and DALYs in DHPM-CRC were 3151.15[95%uncertainty interval(UI)665.74-5696.64]and 83249.31(95%UI 15628.64-151956.31)in China in 2019.However,the number of deaths(2627.57-2528.51)and DALYs(65867.39-55378.65)for DHPM-CRC in the Russian Federation has declined.The fastest increase in ASDALR for DHPM-CRC was observed in Vietnam,Southeast Asia,with an AAPC value of 3.90%[95%confidence interval(CI):3.63%-4.16%],whereas the fastest decline was observed in Kyrgyzstan,Central Asia,with an AAPC value of-2.05%(95%CI:-2.37%to-1.73%).A substantial upward trend in ASR of mortality,years lived with disability,years of life lost,and DALYs from DHPM-CRC changes in 1990-2019 and the final decade(2010-2019)for most Maritime Silk Route members in East Asia,South Asia,Southeast Asia,North Africa,and the Middle East,as well as Central Europe,while those of the most Land Silk Route members in Central Asia and Eastern Europe have decreased markedly(all P<0.05).The ASDALR for DHPM-CRC increased more in males than in females(all P<0.05).For those aged 50-74 years,the ASDALR for DHPM-CRC in 40 members exhibited an increasing trend,except for 20 members,including 7 members in Central Asia,Maldives,and 12 high or high-middle social development index(SDI)members in other regions(all P<0.05).CONCLUSION The burden of DHPM-CRC varies substantially across“B and R”countries and threatens public health.Relevant evidence-based policies and interventions tailored to the different trends of countries in SDIs or Silk Routes should be adopted to reduce the future burden of CRC in“B and R”countries via extensive collaboration.展开更多
This research takes China-aided construction projects in Asia since the Belt and Road Initiative as examples to explore the applicability of Chinese architectural design standards in other Asian countries.So far,the s...This research takes China-aided construction projects in Asia since the Belt and Road Initiative as examples to explore the applicability of Chinese architectural design standards in other Asian countries.So far,the standards demonstrated the highest applicability in South Asia is the best followed by Southeast Asia.Chinese architectural design standards for educational buildings showed the highest applicability,followed by office,medical,and sports buildings.This study puts forward some strategies to improve the applicability of Chinese architectural design standards.These strategies include integrating regionalism and local cultural traditions,optimizing energy efficiency,and aligning designs with local usage habits.This study serves as a reference for similar projects in the future.展开更多
With the advancement of the“Double First-Class”initiative,universities are increasingly focusing on attracting top-tier talent to enhance faculty quality and strengthen academic disciplines.The blind competition for...With the advancement of the“Double First-Class”initiative,universities are increasingly focusing on attracting top-tier talent to enhance faculty quality and strengthen academic disciplines.The blind competition for high-end talent among universities reflects an overshadowing of academic values by economic considerations,neglecting the growth patterns of top talent and the development laws of higher education.This study investigates and reflects on the real-world challenges of faculty mobility in universities,aiming to provide effective guidance for managing university faculty teams.展开更多
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
Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ig...Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ignition mechanism of EFIs directly igniting pyrotechnics.An oscilloscope,a photon Doppler velocimetry,and a plasma spectrum measurement system were employed to obtain information of electric characteristics,impact pressure,and plasma temperature.The results of the electric characteristics and the impact pressure were inconsistent with ignition results.The only thing that the ignition success tests had in common was that their plasma all had a relatively long period of high-temperature duration(HTD).It eventually concludes that the ignition mechanism in this research is the microconvection heat transfer rather than the shock initiation,which differs from that of exploding foil initiators detonating explosives.Furthermore,the methods for evaluating the ignition success of semiconductor bridge initiators are not entirely applicable to the tests mentioned in this paper.The HTD is the critical parameter for judging the ignition success,and it is influenced by two factors:the late time discharge and the energy of the electric explosion.The longer time of the late time discharge and the more energy of the electric explosion,the easier it is to expand the HTD,which improves the probability of the ignition success.展开更多
The collapse pressure is a key parameter when RTPs are applied in harsh deep-water environments.To investigate the collapse of RTPs,numerical simulations and hydrostatic pressure tests are conducted.For the numerical ...The collapse pressure is a key parameter when RTPs are applied in harsh deep-water environments.To investigate the collapse of RTPs,numerical simulations and hydrostatic pressure tests are conducted.For the numerical simulations,the eigenvalue analysis and Riks analysis are combined,in which the Hashin failure criterion and fracture energy stiffness degradation model are used to simulate the progressive failure of composites,and the“infinite”boundary conditions are applied to eliminate the boundary effects.As for the hydrostatic pressure tests,RTP specimens were placed in a hydrostatic chamber after filled with water.It has been observed that the cross-section of the middle part collapses when it reaches the maximum pressure.The collapse pressure obtained from the numerical simulations agrees well with that in the experiment.Meanwhile,the applicability of NASA SP-8007 formula on the collapse pressure prediction was also discussed.It has a relatively greater difference because of the ignorance of the progressive failure of composites.For the parametric study,it is found that RTPs have much higher first-ply-failure pressure when the winding angles are between 50°and 70°.Besides,the effect of debonding and initial ovality,and the contribution of the liner and coating are also discussed.展开更多
Central venous catheterization(CVC) is an invasive procedure for administering fluids,nutrients,and drugs;monitoring central venous pressure;performing pulmonary artery catheterization;and placing transvenous pacemake...Central venous catheterization(CVC) is an invasive procedure for administering fluids,nutrients,and drugs;monitoring central venous pressure;performing pulmonary artery catheterization;and placing transvenous pacemakers in intensive care units and all specialties,from anesthesia to emergency medicine,for the treatment of trauma and hemodynamically unstable pediatric and adult patients.[1,2]Complications have been observed in more than 15% of patients who underwent CVC.Mechanical,infectious,and thrombotic complications have been reported in 5%–19%,5%–26%,and 2%–26% of patients,respectively.[3] Malposition,on the other hand,is common in subclavian catheter insertion and is usually associated with an initially misplaced guidewire.[4]展开更多
An official with the United Nations Environment Programme has welcomed China’s participation in an international initiative that aims to decarbonize the building sector,saying it offers the opportunity for China to s...An official with the United Nations Environment Programme has welcomed China’s participation in an international initiative that aims to decarbonize the building sector,saying it offers the opportunity for China to share its valuable experiences and insight on promoting green buildings.Jonathan Duwyn,program officer of UNEP’s buildings and construction cities unit,made the remarks in a recent interview with China Daily,following the launch of the Buildings Breakthrough on Dec.6at COP28United Nations climate change conference in Dubai,the United Arab Emirates.展开更多
Context: Antiretroviral therapies improve the prognosis of NeuroAIDS contrasting with a high frequency of Minor Neurocognitive Disorders (MND) even in aviremic subjects. Objective: The objective of this study is to pr...Context: Antiretroviral therapies improve the prognosis of NeuroAIDS contrasting with a high frequency of Minor Neurocognitive Disorders (MND) even in aviremic subjects. Objective: The objective of this study is to present the neurological and cognitive profile of People Living with HIV (PLHIV) initiating antiretroviral treatment in Kinshasa in the era of Dolutegravir (DTG). Methods: This is a multicenter, cross-sectional study with a descriptive aim carried out in 16 HIV Outpatient Treatment Centers (OTC) in Kinshasa from October 4, 2021 to February 15, 2022. The International HIV Dementia Scale (IHDS) correlated with the Activities of Daily Living (IADL) scale facilitated the categorization of NeuroCognitive Disorders (NCD) of PLHIV evaluated after carrying out a summary neurological examination. Results: Of the 96 patients recruited, 56.3% were women with a sex ratio of 0.68. The average age was 40.1 ± 12.1 years. The secondary education level was the majority at 64.6%. Malaria (44.8%) and tuberculosis (32.3%) were more common as opportunistic infections. They were alcoholics in (30.2%). Their history was heart disease (15.6%), high blood pressure (18.8%);drug abuse (10.4%). The IHDS score was light in 55.2% of cases. The correlation between IHDS/IADL watches asymptomatic neurocognitive impairments (ANI) in 77.1%, almost all of subjects are found with normal overall functioning (94.8%) and a disturbed neurological examination in 53.1% of cases with a predominance of motor impairments in 79.1%. Conclusion: In view of these results, early and systematic screening of NCD and associated factors remains necessary in our context. .展开更多
To study the effects of the initiation position on the damage and fracture characteristics of linear-charge blasting, blasting model experiments were conducted in this study using computed tomography scanning and thre...To study the effects of the initiation position on the damage and fracture characteristics of linear-charge blasting, blasting model experiments were conducted in this study using computed tomography scanning and three-dimensional reconstruction methods. The fractal damage theory was used to quantify the crack distribution and damage degree of sandstone specimens after blasting. The results showed that regardless of an inverse or top initiation, due to compression deformation and sliding frictional resistance, the plugging medium of the borehole is effective. The energy of the explosive gas near the top of the borehole is consumed. This affects the effective crushing of rocks near the top of the borehole, where the extent of damage to Sections Ⅰ and Ⅱ is less than that of Sections Ⅲ and Ⅳ. In addition, the analysis revealed that under conditions of top initiation, the reflected tensile damage of the rock at the free face of the top of the borehole and the compression deformation of the plug and friction consume more blasting energy, resulting in lower blasting energy efficiency for top initiation. As a result, the overall damage degree of the specimens in the top-initiation group was significantly smaller than that in the inverse-initiation group. Under conditions of inverse initiation, the blasting energy efficiency is greater, causing the specimen to experience greater damage. Therefore, in the engineering practice of rock tunnel cut blasting, to utilize blasting energy effectively and enhance the effects of rock fragmentation, using the inverse-initiation method is recommended. In addition, in three-dimensional(3D) rock blasting, the bottom of the borehole has obvious end effects under the conditions of inverse initiation, and the crack distribution at the bottom of the borehole is trumpet-shaped. The occurrence of an end effect in the 3D linear-charge blasting model experiment is related to the initiation position and the blocking condition.展开更多
Ensemble prediction is widely used to represent the uncertainty of single deterministic Numerical Weather Prediction(NWP) caused by errors in initial conditions(ICs). The traditional Singular Vector(SV) initial pertur...Ensemble prediction is widely used to represent the uncertainty of single deterministic Numerical Weather Prediction(NWP) caused by errors in initial conditions(ICs). The traditional Singular Vector(SV) initial perturbation method tends only to capture synoptic scale initial uncertainty rather than mesoscale uncertainty in global ensemble prediction. To address this issue, a multiscale SV initial perturbation method based on the China Meteorological Administration Global Ensemble Prediction System(CMA-GEPS) is proposed to quantify multiscale initial uncertainty. The multiscale SV initial perturbation approach entails calculating multiscale SVs at different resolutions with multiple linearized physical processes to capture fast-growing perturbations from mesoscale to synoptic scale in target areas and combining these SVs by using a Gaussian sampling method with amplitude coefficients to generate initial perturbations. Following that, the energy norm,energy spectrum, and structure of multiscale SVs and their impact on GEPS are analyzed based on a batch experiment in different seasons. The results show that the multiscale SV initial perturbations can possess more energy and capture more mesoscale uncertainties than the traditional single-SV method. Meanwhile, multiscale SV initial perturbations can reflect the strongest dynamical instability in target areas. Their performances in global ensemble prediction when compared to single-scale SVs are shown to(i) improve the relationship between the ensemble spread and the root-mean-square error and(ii) provide a better probability forecast skill for atmospheric circulation during the late forecast period and for short-to medium-range precipitation. This study provides scientific evidence and application foundations for the design and development of a multiscale SV initial perturbation method for the GEPS.展开更多
5-amino-4-nitrobenzo[1,2-c:3,4-c']bis([1,2,5]oxadiazole)1,6-dioxide(CL-18)exhibits significant potential as an initiating explosive.However,its current synthesis process remains non-scalable due to low yields and ...5-amino-4-nitrobenzo[1,2-c:3,4-c']bis([1,2,5]oxadiazole)1,6-dioxide(CL-18)exhibits significant potential as an initiating explosive.However,its current synthesis process remains non-scalable due to low yields and safety risks.In this study,we have developed a simple and safe synthetic route for CL-18.It was synthesized from 3,5-dihaloanisole in a four-step reaction with an overall yield exceeding 60%,surpassing all reported yields in the literature.Subsequently,recrystallization of CL-18 was successfully achieved by carefully selecting appropriate solvents and antisolvents to reduce its mechanical sensitivity.Ultimately,when DMF-ethanol was employed as the recrystallization solvent system,satisfactory product yield(>90%)and reduced mechanical sensitivity(IS=15 J;FS=216 N)were obtained.Additionally,CL-18 is derived from the rearrangement of oxygen atoms on i-CL-18 furoxan,and a comparative analysis of their physicochemical properties was conducted.The thermal stability of both compounds is similar,with onset decomposition temperatures recorded at 186 and 182℃respectively.Similarly,they exhibit 5 s breaking point temperatures of 236 and 237℃.Additionally,we present novel insights into the positional-isomerization-laser-ignition performance of CL-18 and its isomer i-CL-18 using laser irradiation for the first time.Remarkably,our findings demonstrate that i-CL-18 exhibits enhanced laser sensitivity,as it can be directly ignited by a 1064 nm wavelength laser,whereas CL-18 lacks this characteristic.展开更多
Prey species may have their own optimal escape strategy to balance predation risks and the energetic cost of fleeing.Some species have an advantage when maintaining a short fleeing distance,while others may favour an ...Prey species may have their own optimal escape strategy to balance predation risks and the energetic cost of fleeing.Some species have an advantage when maintaining a short fleeing distance,while others may favour an earlier escape based on microhabitat,size,or body condition.Here,we examined the escape behaviour of the three syntopic Northeast Asian anuran species:Mongolian toads(Strauchbufo raddei),Amur brown frogs(Rana amurensis),and Japanese treefrogs(Dryophytes japonicus)in Mongolia,Russia,China and DPR Korea.We examined flight initiation distance(FID;the distance from a potential predator to the point when the individual starts to flee)and distance fled(DF;distance between flight initiation and flight termination points)of each species and the effects of microhabitat,sex,and body size.Strauchbufo raddei and R.amurensis had a longer FID than D.japonicus,and S.raddei also had a longer DF than D.japonicus.These trends remained similar when dividing FID and DF by a size proxy(snout-vent length)for all individuals.This suggests that the treefrog D.japonicus used a strategy to stay immobile even when they were detected,and the toad S.raddei reacted quicker and more sensitively to predators despite the presence of toxin.Female S.raddei had a significantly longer FID than males suggesting that females are more sensitive to predation risk in this species,but body size was not significant for any of the three species.Our results indicate that the three sympatric species have different escaping strategies,likely related to differences in physiology and crypticity.展开更多
Occasional irregular initial solidification phenomena,including stickers,deep oscillation marks,depressions,and surface cracks of strand shells in continuous casting molds,are important limitations for developing the ...Occasional irregular initial solidification phenomena,including stickers,deep oscillation marks,depressions,and surface cracks of strand shells in continuous casting molds,are important limitations for developing the high-efficiency continuous casting of steels.The application of mold thermal monitoring(MTM) systems,which use thermocouples to detect and respond to temperature variations in molds,has become an effective method to address irregular initial solidification phenomena.Such systems are widely applied in numerous steel companies for sticker breakout prediction.However,monitoring the surface defects of strands remains immature.Hence,indepth research is necessary to utilize the potential advantages and comprehensive monitoring of MTM systems.This paper summarizes what is included in the irregular initial solidification phenomena and systematically reviews the current state of research on these phenomena by the MTM systems.Furthermore,the influences of mold slag behavior on monitoring these phenomena are analyzed.Finally,the remaining problems of the formation mechanisms and investigations of irregular initial solidification phenomena are discussed,and future research directions are proposed.展开更多
Animals must strike a balance between anti-predation behavior and other essential behaviors,such as foraging.Within the same species,strategies may vary on individuals’risk-taking preferences,and in this process the ...Animals must strike a balance between anti-predation behavior and other essential behaviors,such as foraging.Within the same species,strategies may vary on individuals’risk-taking preferences,and in this process the environment is a determinant,in addition to predator regime.The Crested Ibis(Nipponia nippon)exhibits such tendency.This is an endangered species,once inhabiting exclusively in China’s Qinling Mountain.This used to be the sole remaining wild population.However,over recent decades,this population has expanded.A portion has relocated to breed in the lower plain area,which is characterized by elevated level of human activities and landscape complexity.We used flight initiation distance(FID)as an indicator of the ibises’risk-taking preference,particularly their response to human proximity.Additionally,we examined the environmental factors influencing their foraging site selection,including altitude,terrain openness,human activity intensity and human construction.Our findings revealed a significantly shorter FID among individuals relocating to plain habitats,indicating a higher tolerance of human proximity.The results showed that FID decreased with distance to the nearest human settlement.Another finding is that FID was independent of instant human activity intensity and environmental factors(altitude and terrain openness).These different may arise from various combinations of human activity,predation risk,and food abundance within the two habitats.These results provide insights into the in situ conservation of the threatened species within the context of global urbanization.展开更多
This study evaluated the simulation performance of mesoscale convective system(MCS)-induced precipitation,focusing on three selected cases that originated from the Yellow Sea and propagated toward the Korean Peninsula...This study evaluated the simulation performance of mesoscale convective system(MCS)-induced precipitation,focusing on three selected cases that originated from the Yellow Sea and propagated toward the Korean Peninsula.The evaluation was conducted for the European Centre for Medium-Range Weather Forecasts(ECMWF)and National Centers for Environmental Prediction(NCEP)analysis data,as well as the simulation result using them as initial and lateral boundary conditions for the Weather Research and Forecasting model.Particularly,temperature and humidity profiles from 3D dropsonde observations from the National Center for Meteorological Science of the Korea Meteorological Administration served as validation data.Results showed that the ECMWF analysis consistently had smaller errors compared to the NCEP analysis,which exhibited a cold and dry bias in the lower levels below 850 hPa.The model,in terms of the precipitation simulations,particularly for high-intensity precipitation over the Yellow Sea,demonstrated higher accuracy when applying ECMWF analysis data as the initial condition.This advantage also positively influenced the simulation of rainfall events on the Korean Peninsula by reasonably inducing convective-favorable thermodynamic features(i.e.,warm and humid lower-level atmosphere)over the Yellow Sea.In conclusion,this study provides specific information about two global analysis datasets and their impacts on MCS-induced heavy rainfall simulation by employing dropsonde observation data.Furthermore,it suggests the need to enhance the initial field for MCS-induced heavy rainfall simulation and the applicability of assimilating dropsonde data for this purpose in the future.展开更多
This paper developed a statistical damage constitutive model for deep rock by considering the effects of external load and thermal treatment temperature based on the distortion energy.The model parameters were determi...This paper developed a statistical damage constitutive model for deep rock by considering the effects of external load and thermal treatment temperature based on the distortion energy.The model parameters were determined through the extremum features of stress−strain curve.Subsequently,the model predictions were compared with experimental results of marble samples.It is found that when the treatment temperature rises,the coupling damage evolution curve shows an S-shape and the slope of ascending branch gradually decreases during the coupling damage evolution process.At a constant temperature,confining pressure can suppress the expansion of micro-fractures.As the confining pressure increases the rock exhibits ductility characteristics,and the shape of coupling damage curve changes from an S-shape into a quasi-parabolic shape.This model can well characterize the influence of high temperature on the mechanical properties of deep rock and its brittleness-ductility transition characteristics under confining pressure.Also,it is suitable for sandstone and granite,especially in predicting the pre-peak stage and peak stress of stress−strain curve under the coupling action of confining pressure and high temperature.The relevant results can provide a reference for further research on the constitutive relationship of rock-like materials and their engineering applications.展开更多
基金the financial support from the National Natural Science Foundation of China(71934004)Key Projects of the National Social Science Foundation(23AZD065)the Project of the CNOOC Energy Economics Institute(EEI-2022-IESA0009)。
文摘With the implementation of the Belt and Road Initiative, China is deepening its cooperation in oil and gas resources with countries along the Initiative. In order to better mitigate risks and enhance the safety of investments, it is of significant importance to research the oil and gas investment environment in these countries for China's overseas investment macro-layout. This paper proposes an indicator system including 27 indicators from 6 dimensions. On this basis, game theory models combined with global entropy method and analytic hierarchy process are applied to determine the combined weights, and the TOPSIS-GRA model is utilized to assess the risks of oil and gas investment in 76 countries along the Initiative from 2014 to 2021. Finally, the GM(1,1) model is employed to predict risk values for 2022-2025. In conclusion, oil and gas resources and political factors have the greatest impact on investment environment risk, and 12 countries with greater investment potential are selected through cluster analysis in conjunction with the predicted results. The research findings may provide scientific decisionmaking recommendations for the Chinese government and oil enterprises to strengthen oil and gas investment cooperation with countries along the Belt and Road Initiative.
文摘Background: Nigeria, a nation grappling with rapid population growth, economic intricacies, and complex healthcare challenges, particularly in Lagos State, the economic hub and most populous state, faces the challenge of ensuring quality healthcare access. The overview of the effect of quality improvement initiatives in this paper focuses on private healthcare providers in Lagos State, Nigeria. The study assesses the impact of donor-funded quality improvement projects on these private healthcare facilities. It explores the level of participation, perceived support, and tangible effects of the initiatives on healthcare delivery within private healthcare facilities. It also examines how these initiatives influence patient inflow and facility ratings, and bring about additional benefits and improvements, provides insights into the challenges faced by private healthcare providers in implementing quality improvement projects and elicits recommendations for improving the effectiveness of such initiatives. Methods: Qualitative research design was employed for in-depth exploration, utilizing semi-structured interviews. Private healthcare providers in Lagos involved in the SP4FP Quality Improvement Project were purposively sampled for diversity. Face-to-face interviews elicited insights into participation, perceived support, and project effects. Questions covered participation levels, support perception, changes observed, challenges faced, and recommendations. Thematic analysis identified recurring themes from interview transcripts. Adherence to ethical guidelines ensured participant confidentiality and informed consent. Results: Respondents affirmed active involvement in the SP4FP Quality Improvement Project, echoing literature emphasizing private-sector collaboration with the public sector. While acknowledging positive influences on facility ratings, respondents highlighted challenges within the broader Nigerian healthcare landscape affecting patient numbers. Respondents cited tangible improvements, particularly in staff management and patient care processes, validating the positive influence of quality improvement projects. Financial constraints emerged as a significant challenge, aligning with existing literature emphasizing the pragmatic difficulties faced by private healthcare providers. Conclusions: This study illuminates the complex landscape of private healthcare provision in Lagos State, emphasizing the positive impact of donor-funded quality improvement projects. The findings provide nuanced insights, guiding policymakers, healthcare managers, and practitioners toward collaborative, sustainable improvements. As Nigeria progresses, these lessons will be crucial in shaping healthcare policies prioritizing population well-being.
文摘[Objectives]To explore innovative strategies for rural agricultural economic development in the context of the Belt and Road Initiative.[Methods]This research adopts the method of literature review and field research,systematically combs the research results related to the Belt and Road Initiative and rural agricultural economic management,and deeply understands the actual situation of rural agricultural economic management.[Results]The research shows that in the context of the Belt and Road Initiative,the rural agricultural economy is facing new development opportunities and challenges,but there are also some problems.In the new period,we should accelerate the innovative development of rural agricultural economy by promoting market-oriented reform,strengthening scientific and technological innovation,optimizing the industrial structure,deepening international cooperation and other measures.The Belt and Road Initiative provides an important opportunity for the innovation of rural agricultural economic management.Rural agricultural economic management should be actively integrated into the Belt and Road construction to improve the level of rural agricultural economic management.[Conclusions]This study provides useful exploration and reference for the innovation of rural agricultural economic management models,which helps to promote the healthy development of rural agricultural economy and achieve the goal of rural revitalization.
基金Supported by National Natural Science Foundation of China,No.82260532,and No.32060208.
文摘BACKGROUND Colorectal cancer(CRC)plays a significant role in morbidity,mortality,and economic cost in the Belt and Road Initiative(“B and R”)countries.In addition,these countries have a substantial consumption of processed meat.However,the burden and trend of CRC in relation to the consumption of a diet high in processed meat(DHPM-CRC)in these“B and R”countries remain unknown.AIM To analyze the burden and trend of DHPM-CRC in the“B and R”countries from 1990 to 2019.METHODS We used the 2019 Global Burden of Disease Study to collate information regarding the burden of DHPM-CRC.Numbers and age-standardized rates(ASRs)of deaths along with the disability-adjusted life years(DALYs)were determined among the“B and R”countries in 1990 and 2019.Using joinpoint regression analysis,the average annual percent change(AAPC)was used to analyze the temporal trends of age-standardized DALYs rate(ASDALR)from 1990 to 2019 and in the final decade(2010–2019).RESULTS We found geographical differences in the burden of DHPM-CRC among“B and R”countries,with the three highest-ranking countries being the Russian Federation,China,and Ukraine in 1990,and China,the Russian Federation,and Poland in 2019.The burden of DHPM-CRC generally increased in most member countries from 1990 to 2019(all P<0.05).The absolute number of deaths and DALYs in DHPM-CRC were 3151.15[95%uncertainty interval(UI)665.74-5696.64]and 83249.31(95%UI 15628.64-151956.31)in China in 2019.However,the number of deaths(2627.57-2528.51)and DALYs(65867.39-55378.65)for DHPM-CRC in the Russian Federation has declined.The fastest increase in ASDALR for DHPM-CRC was observed in Vietnam,Southeast Asia,with an AAPC value of 3.90%[95%confidence interval(CI):3.63%-4.16%],whereas the fastest decline was observed in Kyrgyzstan,Central Asia,with an AAPC value of-2.05%(95%CI:-2.37%to-1.73%).A substantial upward trend in ASR of mortality,years lived with disability,years of life lost,and DALYs from DHPM-CRC changes in 1990-2019 and the final decade(2010-2019)for most Maritime Silk Route members in East Asia,South Asia,Southeast Asia,North Africa,and the Middle East,as well as Central Europe,while those of the most Land Silk Route members in Central Asia and Eastern Europe have decreased markedly(all P<0.05).The ASDALR for DHPM-CRC increased more in males than in females(all P<0.05).For those aged 50-74 years,the ASDALR for DHPM-CRC in 40 members exhibited an increasing trend,except for 20 members,including 7 members in Central Asia,Maldives,and 12 high or high-middle social development index(SDI)members in other regions(all P<0.05).CONCLUSION The burden of DHPM-CRC varies substantially across“B and R”countries and threatens public health.Relevant evidence-based policies and interventions tailored to the different trends of countries in SDIs or Silk Routes should be adopted to reduce the future burden of CRC in“B and R”countries via extensive collaboration.
基金Humanities and Social Science Research Project of Colleges and Universities in Hebei Province(BJS2022039)2022 Annual Project of Education Science Research 14th“Five-Year”Plan in Hebei Province(2203094)+1 种基金2017 New Engineering Research and Practice Project of Hebei Colleges and Universities(2017GJXGK041)Doctoral Fund of Tangshan Normal University(2022A04)。
文摘This research takes China-aided construction projects in Asia since the Belt and Road Initiative as examples to explore the applicability of Chinese architectural design standards in other Asian countries.So far,the standards demonstrated the highest applicability in South Asia is the best followed by Southeast Asia.Chinese architectural design standards for educational buildings showed the highest applicability,followed by office,medical,and sports buildings.This study puts forward some strategies to improve the applicability of Chinese architectural design standards.These strategies include integrating regionalism and local cultural traditions,optimizing energy efficiency,and aligning designs with local usage habits.This study serves as a reference for similar projects in the future.
基金Sponsored by the Ministry of Education Humanities and Social Sciences Research Planning Fund Project(22YJA880085)the Project of the Center for Party Political Construction Research,Ministry of Industry and Information Technology(GXZY2245).
文摘With the advancement of the“Double First-Class”initiative,universities are increasingly focusing on attracting top-tier talent to enhance faculty quality and strengthen academic disciplines.The blind competition for high-end talent among universities reflects an overshadowing of academic values by economic considerations,neglecting the growth patterns of top talent and the development laws of higher education.This study investigates and reflects on the real-world challenges of faculty mobility in universities,aiming to provide effective guidance for managing university faculty teams.
基金supported by Teaching and Research Project of North China Institute of Aerospace Engineering(JY-2023-19)Humanities and Social Science Research Project of Hebei Education Department(SQ2024272).
文摘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.
文摘Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ignition mechanism of EFIs directly igniting pyrotechnics.An oscilloscope,a photon Doppler velocimetry,and a plasma spectrum measurement system were employed to obtain information of electric characteristics,impact pressure,and plasma temperature.The results of the electric characteristics and the impact pressure were inconsistent with ignition results.The only thing that the ignition success tests had in common was that their plasma all had a relatively long period of high-temperature duration(HTD).It eventually concludes that the ignition mechanism in this research is the microconvection heat transfer rather than the shock initiation,which differs from that of exploding foil initiators detonating explosives.Furthermore,the methods for evaluating the ignition success of semiconductor bridge initiators are not entirely applicable to the tests mentioned in this paper.The HTD is the critical parameter for judging the ignition success,and it is influenced by two factors:the late time discharge and the energy of the electric explosion.The longer time of the late time discharge and the more energy of the electric explosion,the easier it is to expand the HTD,which improves the probability of the ignition success.
基金financially supported by National Natural Science Foundation of China(Grant Nos.52088102,51879249)Fundamental Research Funds for the Central Universities(Grant No.202261055)。
文摘The collapse pressure is a key parameter when RTPs are applied in harsh deep-water environments.To investigate the collapse of RTPs,numerical simulations and hydrostatic pressure tests are conducted.For the numerical simulations,the eigenvalue analysis and Riks analysis are combined,in which the Hashin failure criterion and fracture energy stiffness degradation model are used to simulate the progressive failure of composites,and the“infinite”boundary conditions are applied to eliminate the boundary effects.As for the hydrostatic pressure tests,RTP specimens were placed in a hydrostatic chamber after filled with water.It has been observed that the cross-section of the middle part collapses when it reaches the maximum pressure.The collapse pressure obtained from the numerical simulations agrees well with that in the experiment.Meanwhile,the applicability of NASA SP-8007 formula on the collapse pressure prediction was also discussed.It has a relatively greater difference because of the ignorance of the progressive failure of composites.For the parametric study,it is found that RTPs have much higher first-ply-failure pressure when the winding angles are between 50°and 70°.Besides,the effect of debonding and initial ovality,and the contribution of the liner and coating are also discussed.
文摘Central venous catheterization(CVC) is an invasive procedure for administering fluids,nutrients,and drugs;monitoring central venous pressure;performing pulmonary artery catheterization;and placing transvenous pacemakers in intensive care units and all specialties,from anesthesia to emergency medicine,for the treatment of trauma and hemodynamically unstable pediatric and adult patients.[1,2]Complications have been observed in more than 15% of patients who underwent CVC.Mechanical,infectious,and thrombotic complications have been reported in 5%–19%,5%–26%,and 2%–26% of patients,respectively.[3] Malposition,on the other hand,is common in subclavian catheter insertion and is usually associated with an initially misplaced guidewire.[4]
文摘An official with the United Nations Environment Programme has welcomed China’s participation in an international initiative that aims to decarbonize the building sector,saying it offers the opportunity for China to share its valuable experiences and insight on promoting green buildings.Jonathan Duwyn,program officer of UNEP’s buildings and construction cities unit,made the remarks in a recent interview with China Daily,following the launch of the Buildings Breakthrough on Dec.6at COP28United Nations climate change conference in Dubai,the United Arab Emirates.
文摘Context: Antiretroviral therapies improve the prognosis of NeuroAIDS contrasting with a high frequency of Minor Neurocognitive Disorders (MND) even in aviremic subjects. Objective: The objective of this study is to present the neurological and cognitive profile of People Living with HIV (PLHIV) initiating antiretroviral treatment in Kinshasa in the era of Dolutegravir (DTG). Methods: This is a multicenter, cross-sectional study with a descriptive aim carried out in 16 HIV Outpatient Treatment Centers (OTC) in Kinshasa from October 4, 2021 to February 15, 2022. The International HIV Dementia Scale (IHDS) correlated with the Activities of Daily Living (IADL) scale facilitated the categorization of NeuroCognitive Disorders (NCD) of PLHIV evaluated after carrying out a summary neurological examination. Results: Of the 96 patients recruited, 56.3% were women with a sex ratio of 0.68. The average age was 40.1 ± 12.1 years. The secondary education level was the majority at 64.6%. Malaria (44.8%) and tuberculosis (32.3%) were more common as opportunistic infections. They were alcoholics in (30.2%). Their history was heart disease (15.6%), high blood pressure (18.8%);drug abuse (10.4%). The IHDS score was light in 55.2% of cases. The correlation between IHDS/IADL watches asymptomatic neurocognitive impairments (ANI) in 77.1%, almost all of subjects are found with normal overall functioning (94.8%) and a disturbed neurological examination in 53.1% of cases with a predominance of motor impairments in 79.1%. Conclusion: In view of these results, early and systematic screening of NCD and associated factors remains necessary in our context. .
基金supported by the National Natural Science Foundation of China (No.52204085)the Interdisciplinary Research Project for Young Teachers of USTB,Fundamental Research Funds for the Central Universities (No.FRF-IDRY-21-006).
文摘To study the effects of the initiation position on the damage and fracture characteristics of linear-charge blasting, blasting model experiments were conducted in this study using computed tomography scanning and three-dimensional reconstruction methods. The fractal damage theory was used to quantify the crack distribution and damage degree of sandstone specimens after blasting. The results showed that regardless of an inverse or top initiation, due to compression deformation and sliding frictional resistance, the plugging medium of the borehole is effective. The energy of the explosive gas near the top of the borehole is consumed. This affects the effective crushing of rocks near the top of the borehole, where the extent of damage to Sections Ⅰ and Ⅱ is less than that of Sections Ⅲ and Ⅳ. In addition, the analysis revealed that under conditions of top initiation, the reflected tensile damage of the rock at the free face of the top of the borehole and the compression deformation of the plug and friction consume more blasting energy, resulting in lower blasting energy efficiency for top initiation. As a result, the overall damage degree of the specimens in the top-initiation group was significantly smaller than that in the inverse-initiation group. Under conditions of inverse initiation, the blasting energy efficiency is greater, causing the specimen to experience greater damage. Therefore, in the engineering practice of rock tunnel cut blasting, to utilize blasting energy effectively and enhance the effects of rock fragmentation, using the inverse-initiation method is recommended. In addition, in three-dimensional(3D) rock blasting, the bottom of the borehole has obvious end effects under the conditions of inverse initiation, and the crack distribution at the bottom of the borehole is trumpet-shaped. The occurrence of an end effect in the 3D linear-charge blasting model experiment is related to the initiation position and the blocking condition.
基金supported by the Joint Funds of the Chinese National Natural Science Foundation (NSFC)(Grant No.U2242213)the National Key Research and Development (R&D)Program of the Ministry of Science and Technology of China(Grant No. 2021YFC3000902)the National Science Foundation for Young Scholars (Grant No. 42205166)。
文摘Ensemble prediction is widely used to represent the uncertainty of single deterministic Numerical Weather Prediction(NWP) caused by errors in initial conditions(ICs). The traditional Singular Vector(SV) initial perturbation method tends only to capture synoptic scale initial uncertainty rather than mesoscale uncertainty in global ensemble prediction. To address this issue, a multiscale SV initial perturbation method based on the China Meteorological Administration Global Ensemble Prediction System(CMA-GEPS) is proposed to quantify multiscale initial uncertainty. The multiscale SV initial perturbation approach entails calculating multiscale SVs at different resolutions with multiple linearized physical processes to capture fast-growing perturbations from mesoscale to synoptic scale in target areas and combining these SVs by using a Gaussian sampling method with amplitude coefficients to generate initial perturbations. Following that, the energy norm,energy spectrum, and structure of multiscale SVs and their impact on GEPS are analyzed based on a batch experiment in different seasons. The results show that the multiscale SV initial perturbations can possess more energy and capture more mesoscale uncertainties than the traditional single-SV method. Meanwhile, multiscale SV initial perturbations can reflect the strongest dynamical instability in target areas. Their performances in global ensemble prediction when compared to single-scale SVs are shown to(i) improve the relationship between the ensemble spread and the root-mean-square error and(ii) provide a better probability forecast skill for atmospheric circulation during the late forecast period and for short-to medium-range precipitation. This study provides scientific evidence and application foundations for the design and development of a multiscale SV initial perturbation method for the GEPS.
基金support from the National Natural Science Foundation of China(Grant No.22175160)the Science Challenge Project(Grant No.TZ2018004)。
文摘5-amino-4-nitrobenzo[1,2-c:3,4-c']bis([1,2,5]oxadiazole)1,6-dioxide(CL-18)exhibits significant potential as an initiating explosive.However,its current synthesis process remains non-scalable due to low yields and safety risks.In this study,we have developed a simple and safe synthetic route for CL-18.It was synthesized from 3,5-dihaloanisole in a four-step reaction with an overall yield exceeding 60%,surpassing all reported yields in the literature.Subsequently,recrystallization of CL-18 was successfully achieved by carefully selecting appropriate solvents and antisolvents to reduce its mechanical sensitivity.Ultimately,when DMF-ethanol was employed as the recrystallization solvent system,satisfactory product yield(>90%)and reduced mechanical sensitivity(IS=15 J;FS=216 N)were obtained.Additionally,CL-18 is derived from the rearrangement of oxygen atoms on i-CL-18 furoxan,and a comparative analysis of their physicochemical properties was conducted.The thermal stability of both compounds is similar,with onset decomposition temperatures recorded at 186 and 182℃respectively.Similarly,they exhibit 5 s breaking point temperatures of 236 and 237℃.Additionally,we present novel insights into the positional-isomerization-laser-ignition performance of CL-18 and its isomer i-CL-18 using laser irradiation for the first time.Remarkably,our findings demonstrate that i-CL-18 exhibits enhanced laser sensitivity,as it can be directly ignited by a 1064 nm wavelength laser,whereas CL-18 lacks this characteristic.
基金project was funded by the Foreign Youth Talent Program of the Ministry of Science and Technology of the People’s Republic of China(QN2023014004L)to Amaël BORZÉEa grant from the Korea Environmental Industry and Technology Institute(KEITI 2021002270001)to Yikweon JANGThe research was carried out whithin the state assignment of Ministry of Science and Higher Education of the Russian Federation(theme No.124012200182-1).
文摘Prey species may have their own optimal escape strategy to balance predation risks and the energetic cost of fleeing.Some species have an advantage when maintaining a short fleeing distance,while others may favour an earlier escape based on microhabitat,size,or body condition.Here,we examined the escape behaviour of the three syntopic Northeast Asian anuran species:Mongolian toads(Strauchbufo raddei),Amur brown frogs(Rana amurensis),and Japanese treefrogs(Dryophytes japonicus)in Mongolia,Russia,China and DPR Korea.We examined flight initiation distance(FID;the distance from a potential predator to the point when the individual starts to flee)and distance fled(DF;distance between flight initiation and flight termination points)of each species and the effects of microhabitat,sex,and body size.Strauchbufo raddei and R.amurensis had a longer FID than D.japonicus,and S.raddei also had a longer DF than D.japonicus.These trends remained similar when dividing FID and DF by a size proxy(snout-vent length)for all individuals.This suggests that the treefrog D.japonicus used a strategy to stay immobile even when they were detected,and the toad S.raddei reacted quicker and more sensitively to predators despite the presence of toxin.Female S.raddei had a significantly longer FID than males suggesting that females are more sensitive to predation risk in this species,but body size was not significant for any of the three species.Our results indicate that the three sympatric species have different escaping strategies,likely related to differences in physiology and crypticity.
基金supported by the National Natural Science Foundation of China(No.52274319)。
文摘Occasional irregular initial solidification phenomena,including stickers,deep oscillation marks,depressions,and surface cracks of strand shells in continuous casting molds,are important limitations for developing the high-efficiency continuous casting of steels.The application of mold thermal monitoring(MTM) systems,which use thermocouples to detect and respond to temperature variations in molds,has become an effective method to address irregular initial solidification phenomena.Such systems are widely applied in numerous steel companies for sticker breakout prediction.However,monitoring the surface defects of strands remains immature.Hence,indepth research is necessary to utilize the potential advantages and comprehensive monitoring of MTM systems.This paper summarizes what is included in the irregular initial solidification phenomena and systematically reviews the current state of research on these phenomena by the MTM systems.Furthermore,the influences of mold slag behavior on monitoring these phenomena are analyzed.Finally,the remaining problems of the formation mechanisms and investigations of irregular initial solidification phenomena are discussed,and future research directions are proposed.
基金supported by National Natural Science Foundation of China(No.32270554 to CD)。
文摘Animals must strike a balance between anti-predation behavior and other essential behaviors,such as foraging.Within the same species,strategies may vary on individuals’risk-taking preferences,and in this process the environment is a determinant,in addition to predator regime.The Crested Ibis(Nipponia nippon)exhibits such tendency.This is an endangered species,once inhabiting exclusively in China’s Qinling Mountain.This used to be the sole remaining wild population.However,over recent decades,this population has expanded.A portion has relocated to breed in the lower plain area,which is characterized by elevated level of human activities and landscape complexity.We used flight initiation distance(FID)as an indicator of the ibises’risk-taking preference,particularly their response to human proximity.Additionally,we examined the environmental factors influencing their foraging site selection,including altitude,terrain openness,human activity intensity and human construction.Our findings revealed a significantly shorter FID among individuals relocating to plain habitats,indicating a higher tolerance of human proximity.The results showed that FID decreased with distance to the nearest human settlement.Another finding is that FID was independent of instant human activity intensity and environmental factors(altitude and terrain openness).These different may arise from various combinations of human activity,predation risk,and food abundance within the two habitats.These results provide insights into the in situ conservation of the threatened species within the context of global urbanization.
基金supported by the Korea Meteorological Administration Research and Development Program “Developing Application Technology for Atmospheric Research Aircraft” (Grant No. KMA2018-00222)
文摘This study evaluated the simulation performance of mesoscale convective system(MCS)-induced precipitation,focusing on three selected cases that originated from the Yellow Sea and propagated toward the Korean Peninsula.The evaluation was conducted for the European Centre for Medium-Range Weather Forecasts(ECMWF)and National Centers for Environmental Prediction(NCEP)analysis data,as well as the simulation result using them as initial and lateral boundary conditions for the Weather Research and Forecasting model.Particularly,temperature and humidity profiles from 3D dropsonde observations from the National Center for Meteorological Science of the Korea Meteorological Administration served as validation data.Results showed that the ECMWF analysis consistently had smaller errors compared to the NCEP analysis,which exhibited a cold and dry bias in the lower levels below 850 hPa.The model,in terms of the precipitation simulations,particularly for high-intensity precipitation over the Yellow Sea,demonstrated higher accuracy when applying ECMWF analysis data as the initial condition.This advantage also positively influenced the simulation of rainfall events on the Korean Peninsula by reasonably inducing convective-favorable thermodynamic features(i.e.,warm and humid lower-level atmosphere)over the Yellow Sea.In conclusion,this study provides specific information about two global analysis datasets and their impacts on MCS-induced heavy rainfall simulation by employing dropsonde observation data.Furthermore,it suggests the need to enhance the initial field for MCS-induced heavy rainfall simulation and the applicability of assimilating dropsonde data for this purpose in the future.
基金Project(11272119)supported by the National Natural Science Foundation of China。
文摘This paper developed a statistical damage constitutive model for deep rock by considering the effects of external load and thermal treatment temperature based on the distortion energy.The model parameters were determined through the extremum features of stress−strain curve.Subsequently,the model predictions were compared with experimental results of marble samples.It is found that when the treatment temperature rises,the coupling damage evolution curve shows an S-shape and the slope of ascending branch gradually decreases during the coupling damage evolution process.At a constant temperature,confining pressure can suppress the expansion of micro-fractures.As the confining pressure increases the rock exhibits ductility characteristics,and the shape of coupling damage curve changes from an S-shape into a quasi-parabolic shape.This model can well characterize the influence of high temperature on the mechanical properties of deep rock and its brittleness-ductility transition characteristics under confining pressure.Also,it is suitable for sandstone and granite,especially in predicting the pre-peak stage and peak stress of stress−strain curve under the coupling action of confining pressure and high temperature.The relevant results can provide a reference for further research on the constitutive relationship of rock-like materials and their engineering applications.