This experimental study assesses the effectiveness of traditional and nano-materials in enhancing the physical and mechanical properties of deteriorated sandstone from Ramesses III Temple, Karnak, Luxor, Egypt. Treatm...This experimental study assesses the effectiveness of traditional and nano-materials in enhancing the physical and mechanical properties of deteriorated sandstone from Ramesses III Temple, Karnak, Luxor, Egypt. Treatments included Nano Estel (5%), Paraloid B-72 (3%), Paraloid B-72/Nano Estel (3%/5%), and ethyl silicates. Treated samples underwent Scanning Electron Microscopy (SEM) and physical/mechanical testing. Results show that Paraloid B-72/Nano Estel (3%/5%) yielded optimal consolidation, significantly improving sandstone’s physical and mechanical properties.展开更多
From 2001 to 2012,many local governments in China closed down village teaching sites for primary school students in the first and second grades,consolidating them into larger township schools more distant from village...From 2001 to 2012,many local governments in China closed down village teaching sites for primary school students in the first and second grades,consolidating them into larger township schools more distant from village students’homes.School closure and consolidation are particularly striking in China’s central and western regions,where swathes of rural labor migrated to cities for jobs.As a result,numerous primary school pupils are forced to study at boarding schools in the first and second grades,which is considered as too early for pupils to live without parental care.This paper employs survey data from 137 township schools with boarding qualifications collected by a project team consisting of researchers from the China Institute for Educational Finance Research(CIEFR)of Peking University,the Institute of Population and Labor Economics of the Chinese Academy of Social Sciences(IPLE-CASS)and the Capital University of Economics and Business(CUEB).By matching the home-school distance with village teaching site information as the proxy variable for the school consolidation policy,this paper evaluates the policy's impact on the likelyhood of premature boarding for primary school pupils,as well as the impact on their human capital accumulation.Our study finds that the creation of teaching sites makes it less likely for primary school pupils to board at school.Premature boarding impedes children’s human capital accumulation,and the harmful effect is particularly striking for children lacking pastoral teachers,raised by grandparents and from families above average income levels,as well as girls.展开更多
BACKGROUND Immune checkpoint inhibitor-associated interstitial lung disease(ICI-ILD)and opportunistic pneumonias are the main pulmonary complications during immunotherapy for malignancies.The organizing pneumonia(OP)p...BACKGROUND Immune checkpoint inhibitor-associated interstitial lung disease(ICI-ILD)and opportunistic pneumonias are the main pulmonary complications during immunotherapy for malignancies.The organizing pneumonia(OP)pattern is one of the common radiological manifestations of ICI-ILD,and OP is the most common cause of reversed halo cycles and consolidations.However,opportunistic pneumonias should be excluded.CASE SUMMARY In this report,we described a case of a 44-year-old man with esophageal cancer who showed multiple reversed-halo cycles and consolidations on chest computed tomography(CT)after he had a cold during immunotherapy.He was diagnosed with esophageal squamous-cell cancer(T2NIM0)after surgery.Then,he was successfully treated with 6 cycles of chemotherapy plus tislelizumab,one cycle of radiotherapy and 9 cycles of tislelizumab.Two months later,he complained of low-grade fever and cough with nonpurulent sputum after he had a cold.Community-acquired pneumonia was considered,but moxifloxacin was ineffective.Chest CT showed multiple reversed-halo cycles and consolidations.Mycobacterium tuberculosis was identified with next-generation sequence analysis of bronchoalveolar lavage fluid(BALF).Two months later,he improved with standard anti-tuberculosis medications.Both the cycles and consolidations disappeared in the repeat CT after 6 mo of medications.CONCLUSION When chest CT shows reversed-halo cycles and consolidations in patients during anticancer immunotherapy,both ICI-ILD and infectious pneumonia should be considered.BALF microbiological analysis was helpful to differentiate them.展开更多
Virtual machine(VM)consolidation aims to run VMs on the least number of physical machines(PMs).The optimal consolidation significantly reduces energy consumption(EC),quality of service(QoS)in applications,and resource...Virtual machine(VM)consolidation aims to run VMs on the least number of physical machines(PMs).The optimal consolidation significantly reduces energy consumption(EC),quality of service(QoS)in applications,and resource utilization.This paper proposes a prediction-basedmulti-objective VMconsolidation approach to search for the best mapping between VMs and PMs with good timeliness and practical value.We use a hybrid model based on Auto-Regressive Integrated Moving Average(ARIMA)and Support Vector Regression(SVR)(HPAS)as a prediction model and consolidate VMs to PMs based on prediction results by HPAS,aiming at minimizing the total EC,performance degradation(PD),migration cost(MC)and resource wastage(RW)simultaneously.Experimental results usingMicrosoft Azure trace show the proposed approach has better prediction accuracy and overcomes the multi-objective consolidation approach without prediction(i.e.,Non-dominated sorting genetic algorithm 2,Nsga2)and the renowned Overload Host Detection(OHD)approaches without prediction,such as Linear Regression(LR),Median Absolute Deviation(MAD)and Inter-Quartile Range(IQR).展开更多
The vacuum-assisted prefabricated horizontal drain offers a promising method for strengthening soil slurry,allowing simultaneous filling and vacuum-dewatering via staged construction.However,there is limited research ...The vacuum-assisted prefabricated horizontal drain offers a promising method for strengthening soil slurry,allowing simultaneous filling and vacuum-dewatering via staged construction.However,there is limited research on the unique characteristics of staged filling.This study aims to investigate the vacuum consolidation process of staged-filled soil slurry through laboratory model tests and numerical simulations,also assessing the impact of anionic polyacrylamide.Comparative analyses are conducted between vacuum consolidation with and without anionic polyacrylamide,as well as self-weight consolidation without anionic polyacrylamide.Results reveal contour lines of excess pore pressure,water content,and soil strength forming an ellipse around the prefabricated horizontal drain board.During the consolidation process,a higher degree of consolidation,lower water content,and higher soil strength were observed closer to the prefabricated horizontal drain board.After treatment,the uppermost filling layer exhibits an average water content that was approximately 40%higher than the lower filling layer,and its average strength was about 60%lower.This discrepancy is primarily due to the absence of sealing on the top surface and the relatively short vacuum consolidation time caused by staged filling.The introduction of anionic polyacrylamide-induced flocculation significantly improves the initial consolidation rate but minimally affects the dewatering capacity of vacuum preloading.Using flocculant can enhance both the staged filling rate and soil strength(by 1e2 times).Additionally,employing a staggered arrangement between different prefabricated horizontal drain layers is advisable to prevent top-down penetration in areas with low soil strength.展开更多
Freight transportation in urban areas has increased significantly in a shorter period due to the widespread use of e-commerce, fast delivery, and population growth. Recently, a noticeable government initiative aimed a...Freight transportation in urban areas has increased significantly in a shorter period due to the widespread use of e-commerce, fast delivery, and population growth. Recently, a noticeable government initiative aimed at creating an effective, acceptable, and sustainable city logistics policy. This paper examines freight consolidation as a transportation strategy for optimizing last-mile delivery costs. Freight consolidation involves combining smaller shipments from various origins into a single, larger shipment for more efficient transportation to a common destination. This approach is particularly beneficial for last-mile delivery, where frequent deliveries of smaller quantities are frequently visible. Finally, we provide an illustrative example targeting urban freight stakeholders for practicing possible consolidation methodology. The result in the illustrative example shows that freight with 3-day consolidation, despite the delay penalty, is cheaper than daily shipping, and both are cheaper than 2-day consolidated shipping. The study will benefit urban businesses and freight services.展开更多
The utilization of stone columns has emerged as a popular ground improvement strategy,whereas the drainage performance can be adversely hampered by clogging effect.Despite the ample progress of calculation methods for...The utilization of stone columns has emerged as a popular ground improvement strategy,whereas the drainage performance can be adversely hampered by clogging effect.Despite the ample progress of calculation methods for the consolidation of stone column-improved ground,theoretical investigations into the clogging effect have not been thoroughly explored.Furthermore,it is imperative to involve the column consolidation deformation to mitigate computational error on the consolidation of composite ground with high replacement ratios.In this context,an analytical model accounting for the initial clogging and coupled time and depth-dependent clogging of stone columns is established.Then,the resulting governing equations and analytical solutions are obtained under a new flow continuity relationship to incorporate column consolidation deformation.The accuracy and reliability of the proposed model are illustrated by degradation analysis and case studies with good agreements.Subsequently,the computed results of the current study are juxtaposed against the existing models,and an in-depth assessment of the impacts of several crucial parameters on the consolidation behavior is conducted.The results reveal that ignoring column consolidation deformation leads to an overestimate of the consolidation rate,with maximum error reaching up to 16%as the replacement ratio increases.Furthermore,the initial clogging also has a significant influence on the consolidation performance.Additionally,the increment of depth and time-clogging factors a and b will induce a noticeable retardation of the consolidation process,particularly in the later stage.展开更多
The wave-induced liquefaction of seabed is responsible for causing damage to marine structures.Particle composition and consolidation degree are the key factors affecting the pore water pressure response and liquefact...The wave-induced liquefaction of seabed is responsible for causing damage to marine structures.Particle composition and consolidation degree are the key factors affecting the pore water pressure response and liquefaction behavior of the seabed under wave action.The present study conducted wave flume experiments on silt and silty fine sand beds with varying particle compositions.Furthermore,a comprehensive analysis of the differences and underlying reasons for liquefaction behavior in two different types of soil was conducted from both macroscopic and microscopic perspectives.The experimental results indicate that the silt bed necessitates a lower wave load intensity to attain the liquefaction state in comparison to the silty fine sand bed.Additionally,the duration and development depth of liquefaction are greater in the silt bed.The dissimilarity in liquefaction behavior between the two types of soil can be attributed to the variation in their permeability and plastic deformation capacity.The permeability coefficient and compression modulus of silt are lower than those of silty fine sand.Consequently,silt is more prone to the accumulation of pore pressure and subsequent liquefaction under external loading.Prior research has demonstrated that silt beds with varying consolidation degrees exhibit distinct initial failure modes.Specifically,a dense bed undergoes shear failure,whereas a loose bed experiences initial liquefaction failure.This study utilized discrete element simulation to examine the microscopic mechanisms that underlie this phenomenon.展开更多
No consensus has been reached in the academic community regarding the principles and criteria for the application of substantive consolidation in bankruptcy.However,in judicial practices,the substantive consolidation ...No consensus has been reached in the academic community regarding the principles and criteria for the application of substantive consolidation in bankruptcy.However,in judicial practices,the substantive consolidation doctrine has been applied to handle enterprise bankruptcy cases.This paper summarizes the dilemmas in the judicial application of substantive consolidation in bankruptcy through case analyses.The paper also proposes pathways for improving the judicial application criteria for the substantive consolidation in bankruptcy of affiliated enterprises in China,that is,comprehensively assessing the degree of corporate personality confusion from multiple perspectives;considering the cost and difficulty of asset segregation as supplementary elements;weighing the protection of creditors’interests;and taking into account the feasibility and necessity of consolidation and reorganization.展开更多
One of the most effective methods for sand control is the chemical consolidation of sandstone structures.In this paper,the impacts of crude oil and brine in the static state and the impact of the flow rates of the flu...One of the most effective methods for sand control is the chemical consolidation of sandstone structures.In this paper,the impacts of crude oil and brine in the static state and the impact of the flow rates of the fluids in the dynamic state have been assessed at the reservoir conditions.The analyses in this research were Young’s modulus,compressive strength,porosity,and permeability which were done on core samples after and before fluid contact.Samples made with two different resins showed good resistance to crude oil in both states.No considerable change was seen in the analyses even at high crude oil injection rates in the dynamic state.Conversely,brine caused a noticeable change in the analyses in both states.In the presence of brine at the static state,Young’s modulus and compressive strength respectively decreased by 37.5%and 34.5%for epoxy cores,whereas these parameters respectively reduced by 30%and 41%for furan cores.In brine presence at the dynamic state,compressive strength reduction was 10.28 MPa for furan and 6.28 MPa for epoxy samples and their compressive strength reached 16.75 MPa and 26.54 MPa respectively which are higher than the critical point to be known as weak sandstone core.Moreover,Young’s modulus decrease values for furan and epoxy samples were respectively 0.37 GPa and 0.44 GPa.Therefore,brine had a more destructive effect on the mechanical characteristics of samples in the static state than the dynamic one for two resins.In addition,brine injection increased permeability by about 13.6%for furan and 34.8%for epoxy.Also,porosity raised by about 21.8%for furan,and 19%for epoxy by brine injection.The results showed that the chemical sand consolidation weakens in the face of brine production along with crude oil which can lead to increasing cost of oil production and treating wellbore again.展开更多
Shape irregularity,a sub-factor of parcel fragmentation is a problem that hinders sustainable agriculture and is solved using land consolidation projects.Determination of the parcel shape degree contributes significan...Shape irregularity,a sub-factor of parcel fragmentation is a problem that hinders sustainable agriculture and is solved using land consolidation projects.Determination of the parcel shape degree contributes significantly to spatial prioritization where there is also a high probability of achieving positive effects of consolidation projects.This study aims to determine the shape degree of the agricultural parcels both at singular and rural county scales in Tekirdag Province,Turkey in 2020 by combining the parcel shape index(PSI) with the minimum bounding geometry index(MBG) to improve parcel scores.Hot-spot zones of the highly irregular and near optimum parcels were also determined using Getis-Ord G_(i)^(*) statistic.The parcel degrees were classified into four categories,namely highly irregular,irregular,regular and near optimum.The obtained unweighted scores of the parameters exhibit deviations from the expected values.After weighting by pairwise comparison,the values approached ideal scores.Among 346 740 parcels,53% were highly irregular and irregular and 47% were regular and near optimum shapes after weighting whereas these were 70% and 30%,respectively before weighting.The average parcel degree of 63 rural counties was regular while the average parcel degree of the remaining 264 rural counties was irregular.The combined use of PSI and MBG index improved the correctness of the parcel shape score.It could be suggested to use as a tool in land consolidation prioritization.展开更多
Pore water pressure fluctuations are an inherent phenomenon during the consolidation process of clayey foundations, and understanding its mechanism is crucial for comprehending the consolidation process and addressing...Pore water pressure fluctuations are an inherent phenomenon during the consolidation process of clayey foundations, and understanding its mechanism is crucial for comprehending the consolidation process and addressing issues such as drainage blockage during consolidation. This study investigates the consolidation behavior of clay, particularly focusing on pore water pressure fluctuations during the consolidation process of dredged marine sedimentary mud from Daya Bay, Guangdong Province. Given the prevalent use of clay in large-scale construction projects in southern China, understanding the factors influencing pore water pressure is crucial for optimizing consolidation times and improving construction efficacy. Using a custom vacuum preloading model, the research explores the impact of sodium hydroxide on the bound water content and its subsequent effects on pore water pressure dynamics. Experimental findings reveal a distinct inflection point in pore water pressure dissipation, suggesting that particle migration and bound water interactions contribute to the observed fluctuations. These results provide valuable insights for enhancing engineering applications in clay consolidation and mitigating drainage issues, ultimately informing construction practices and reducing project timelines.展开更多
Studying the spatiotemporal variations in ecosystem services and their interrelationships on the Loess Plateau against the background of the gully control and land consolidation(GCLC)project has significant implicatio...Studying the spatiotemporal variations in ecosystem services and their interrelationships on the Loess Plateau against the background of the gully control and land consolidation(GCLC)project has significant implications for ecological protection and quality development of the Yellow River Basin.Therefore,in this study,we took Yan'an City,Shaanxi Province of China,as the study area,selected four typical ecosystem services,including soil conservation service,water yield service,carbon storage service,and habitat quality service,and quantitatively evaluated the spatiotemporal variation characteristics and trade-offs and synergies of ecosystem services from 2010 to 2018 using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.We also analysed the relationship between the GCLC project and regional ecosystem service changes in various regions(including 1 city,2 districts,and 10 counties)of Yan'an City and proposed a coordinated development strategy between the GCLC project and the ecological environment.The results showed that,from 2010 to 2018,soil conservation service decreased by 7.76%,while the other three ecosystem services changed relatively little,with water yield service increasing by 0.56% and carbon storage service and habitat quality service decreasing by 0.16% and 0.14%,respectively.The ecological environment of Yan'an City developed in a balanced way between 2010 and 2018,and the four ecosystem services showed synergistic relationships,among which the synergistic relationships between soil conservation service and water yield service and between carbon storage service and habitat quality service were significant.The GCLC project had a negative impact on the ecosystem services of Yan'an City,and the impact on carbon storage service was more significant.This study provides a theoretical basis for the scientific evaluation of the ecological benefits of the GCLC project and the realization of a win-win situation between food security and ecological security.展开更多
文摘This experimental study assesses the effectiveness of traditional and nano-materials in enhancing the physical and mechanical properties of deteriorated sandstone from Ramesses III Temple, Karnak, Luxor, Egypt. Treatments included Nano Estel (5%), Paraloid B-72 (3%), Paraloid B-72/Nano Estel (3%/5%), and ethyl silicates. Treated samples underwent Scanning Electron Microscopy (SEM) and physical/mechanical testing. Results show that Paraloid B-72/Nano Estel (3%/5%) yielded optimal consolidation, significantly improving sandstone’s physical and mechanical properties.
文摘From 2001 to 2012,many local governments in China closed down village teaching sites for primary school students in the first and second grades,consolidating them into larger township schools more distant from village students’homes.School closure and consolidation are particularly striking in China’s central and western regions,where swathes of rural labor migrated to cities for jobs.As a result,numerous primary school pupils are forced to study at boarding schools in the first and second grades,which is considered as too early for pupils to live without parental care.This paper employs survey data from 137 township schools with boarding qualifications collected by a project team consisting of researchers from the China Institute for Educational Finance Research(CIEFR)of Peking University,the Institute of Population and Labor Economics of the Chinese Academy of Social Sciences(IPLE-CASS)and the Capital University of Economics and Business(CUEB).By matching the home-school distance with village teaching site information as the proxy variable for the school consolidation policy,this paper evaluates the policy's impact on the likelyhood of premature boarding for primary school pupils,as well as the impact on their human capital accumulation.Our study finds that the creation of teaching sites makes it less likely for primary school pupils to board at school.Premature boarding impedes children’s human capital accumulation,and the harmful effect is particularly striking for children lacking pastoral teachers,raised by grandparents and from families above average income levels,as well as girls.
基金Supported by National High Level Hospital Clinical Research Funding,No.2022-PUMCH-C-069 and No.2022-PUMCH-A-009.
文摘BACKGROUND Immune checkpoint inhibitor-associated interstitial lung disease(ICI-ILD)and opportunistic pneumonias are the main pulmonary complications during immunotherapy for malignancies.The organizing pneumonia(OP)pattern is one of the common radiological manifestations of ICI-ILD,and OP is the most common cause of reversed halo cycles and consolidations.However,opportunistic pneumonias should be excluded.CASE SUMMARY In this report,we described a case of a 44-year-old man with esophageal cancer who showed multiple reversed-halo cycles and consolidations on chest computed tomography(CT)after he had a cold during immunotherapy.He was diagnosed with esophageal squamous-cell cancer(T2NIM0)after surgery.Then,he was successfully treated with 6 cycles of chemotherapy plus tislelizumab,one cycle of radiotherapy and 9 cycles of tislelizumab.Two months later,he complained of low-grade fever and cough with nonpurulent sputum after he had a cold.Community-acquired pneumonia was considered,but moxifloxacin was ineffective.Chest CT showed multiple reversed-halo cycles and consolidations.Mycobacterium tuberculosis was identified with next-generation sequence analysis of bronchoalveolar lavage fluid(BALF).Two months later,he improved with standard anti-tuberculosis medications.Both the cycles and consolidations disappeared in the repeat CT after 6 mo of medications.CONCLUSION When chest CT shows reversed-halo cycles and consolidations in patients during anticancer immunotherapy,both ICI-ILD and infectious pneumonia should be considered.BALF microbiological analysis was helpful to differentiate them.
基金funded by Science and Technology Department of Shaanxi Province,Grant Numbers:2019GY-020 and 2024JC-YBQN-0730.
文摘Virtual machine(VM)consolidation aims to run VMs on the least number of physical machines(PMs).The optimal consolidation significantly reduces energy consumption(EC),quality of service(QoS)in applications,and resource utilization.This paper proposes a prediction-basedmulti-objective VMconsolidation approach to search for the best mapping between VMs and PMs with good timeliness and practical value.We use a hybrid model based on Auto-Regressive Integrated Moving Average(ARIMA)and Support Vector Regression(SVR)(HPAS)as a prediction model and consolidate VMs to PMs based on prediction results by HPAS,aiming at minimizing the total EC,performance degradation(PD),migration cost(MC)and resource wastage(RW)simultaneously.Experimental results usingMicrosoft Azure trace show the proposed approach has better prediction accuracy and overcomes the multi-objective consolidation approach without prediction(i.e.,Non-dominated sorting genetic algorithm 2,Nsga2)and the renowned Overload Host Detection(OHD)approaches without prediction,such as Linear Regression(LR),Median Absolute Deviation(MAD)and Inter-Quartile Range(IQR).
基金supported by the Research Grants Council of Hong Kong Special Administrative Region Government of China(Grant Nos.15210322 and R5037-18)the financial support(Grant No.86902-00000240)from Shenzhen University.
文摘The vacuum-assisted prefabricated horizontal drain offers a promising method for strengthening soil slurry,allowing simultaneous filling and vacuum-dewatering via staged construction.However,there is limited research on the unique characteristics of staged filling.This study aims to investigate the vacuum consolidation process of staged-filled soil slurry through laboratory model tests and numerical simulations,also assessing the impact of anionic polyacrylamide.Comparative analyses are conducted between vacuum consolidation with and without anionic polyacrylamide,as well as self-weight consolidation without anionic polyacrylamide.Results reveal contour lines of excess pore pressure,water content,and soil strength forming an ellipse around the prefabricated horizontal drain board.During the consolidation process,a higher degree of consolidation,lower water content,and higher soil strength were observed closer to the prefabricated horizontal drain board.After treatment,the uppermost filling layer exhibits an average water content that was approximately 40%higher than the lower filling layer,and its average strength was about 60%lower.This discrepancy is primarily due to the absence of sealing on the top surface and the relatively short vacuum consolidation time caused by staged filling.The introduction of anionic polyacrylamide-induced flocculation significantly improves the initial consolidation rate but minimally affects the dewatering capacity of vacuum preloading.Using flocculant can enhance both the staged filling rate and soil strength(by 1e2 times).Additionally,employing a staggered arrangement between different prefabricated horizontal drain layers is advisable to prevent top-down penetration in areas with low soil strength.
文摘Freight transportation in urban areas has increased significantly in a shorter period due to the widespread use of e-commerce, fast delivery, and population growth. Recently, a noticeable government initiative aimed at creating an effective, acceptable, and sustainable city logistics policy. This paper examines freight consolidation as a transportation strategy for optimizing last-mile delivery costs. Freight consolidation involves combining smaller shipments from various origins into a single, larger shipment for more efficient transportation to a common destination. This approach is particularly beneficial for last-mile delivery, where frequent deliveries of smaller quantities are frequently visible. Finally, we provide an illustrative example targeting urban freight stakeholders for practicing possible consolidation methodology. The result in the illustrative example shows that freight with 3-day consolidation, despite the delay penalty, is cheaper than daily shipping, and both are cheaper than 2-day consolidated shipping. The study will benefit urban businesses and freight services.
基金funding support from the National Natural Science Foundation of China(Grant Nos.52178373 and 51878657).
文摘The utilization of stone columns has emerged as a popular ground improvement strategy,whereas the drainage performance can be adversely hampered by clogging effect.Despite the ample progress of calculation methods for the consolidation of stone column-improved ground,theoretical investigations into the clogging effect have not been thoroughly explored.Furthermore,it is imperative to involve the column consolidation deformation to mitigate computational error on the consolidation of composite ground with high replacement ratios.In this context,an analytical model accounting for the initial clogging and coupled time and depth-dependent clogging of stone columns is established.Then,the resulting governing equations and analytical solutions are obtained under a new flow continuity relationship to incorporate column consolidation deformation.The accuracy and reliability of the proposed model are illustrated by degradation analysis and case studies with good agreements.Subsequently,the computed results of the current study are juxtaposed against the existing models,and an in-depth assessment of the impacts of several crucial parameters on the consolidation behavior is conducted.The results reveal that ignoring column consolidation deformation leads to an overestimate of the consolidation rate,with maximum error reaching up to 16%as the replacement ratio increases.Furthermore,the initial clogging also has a significant influence on the consolidation performance.Additionally,the increment of depth and time-clogging factors a and b will induce a noticeable retardation of the consolidation process,particularly in the later stage.
基金The National Natural Science Foundation of China under contract No.41976049the Opening Foundation of Marine Ecological Restoration and Smart Ocean Engineering Research Center of Hebei Province under contract No.HBMESO2306。
文摘The wave-induced liquefaction of seabed is responsible for causing damage to marine structures.Particle composition and consolidation degree are the key factors affecting the pore water pressure response and liquefaction behavior of the seabed under wave action.The present study conducted wave flume experiments on silt and silty fine sand beds with varying particle compositions.Furthermore,a comprehensive analysis of the differences and underlying reasons for liquefaction behavior in two different types of soil was conducted from both macroscopic and microscopic perspectives.The experimental results indicate that the silt bed necessitates a lower wave load intensity to attain the liquefaction state in comparison to the silty fine sand bed.Additionally,the duration and development depth of liquefaction are greater in the silt bed.The dissimilarity in liquefaction behavior between the two types of soil can be attributed to the variation in their permeability and plastic deformation capacity.The permeability coefficient and compression modulus of silt are lower than those of silty fine sand.Consequently,silt is more prone to the accumulation of pore pressure and subsequent liquefaction under external loading.Prior research has demonstrated that silt beds with varying consolidation degrees exhibit distinct initial failure modes.Specifically,a dense bed undergoes shear failure,whereas a loose bed experiences initial liquefaction failure.This study utilized discrete element simulation to examine the microscopic mechanisms that underlie this phenomenon.
文摘No consensus has been reached in the academic community regarding the principles and criteria for the application of substantive consolidation in bankruptcy.However,in judicial practices,the substantive consolidation doctrine has been applied to handle enterprise bankruptcy cases.This paper summarizes the dilemmas in the judicial application of substantive consolidation in bankruptcy through case analyses.The paper also proposes pathways for improving the judicial application criteria for the substantive consolidation in bankruptcy of affiliated enterprises in China,that is,comprehensively assessing the degree of corporate personality confusion from multiple perspectives;considering the cost and difficulty of asset segregation as supplementary elements;weighing the protection of creditors’interests;and taking into account the feasibility and necessity of consolidation and reorganization.
文摘One of the most effective methods for sand control is the chemical consolidation of sandstone structures.In this paper,the impacts of crude oil and brine in the static state and the impact of the flow rates of the fluids in the dynamic state have been assessed at the reservoir conditions.The analyses in this research were Young’s modulus,compressive strength,porosity,and permeability which were done on core samples after and before fluid contact.Samples made with two different resins showed good resistance to crude oil in both states.No considerable change was seen in the analyses even at high crude oil injection rates in the dynamic state.Conversely,brine caused a noticeable change in the analyses in both states.In the presence of brine at the static state,Young’s modulus and compressive strength respectively decreased by 37.5%and 34.5%for epoxy cores,whereas these parameters respectively reduced by 30%and 41%for furan cores.In brine presence at the dynamic state,compressive strength reduction was 10.28 MPa for furan and 6.28 MPa for epoxy samples and their compressive strength reached 16.75 MPa and 26.54 MPa respectively which are higher than the critical point to be known as weak sandstone core.Moreover,Young’s modulus decrease values for furan and epoxy samples were respectively 0.37 GPa and 0.44 GPa.Therefore,brine had a more destructive effect on the mechanical characteristics of samples in the static state than the dynamic one for two resins.In addition,brine injection increased permeability by about 13.6%for furan and 34.8%for epoxy.Also,porosity raised by about 21.8%for furan,and 19%for epoxy by brine injection.The results showed that the chemical sand consolidation weakens in the face of brine production along with crude oil which can lead to increasing cost of oil production and treating wellbore again.
文摘Shape irregularity,a sub-factor of parcel fragmentation is a problem that hinders sustainable agriculture and is solved using land consolidation projects.Determination of the parcel shape degree contributes significantly to spatial prioritization where there is also a high probability of achieving positive effects of consolidation projects.This study aims to determine the shape degree of the agricultural parcels both at singular and rural county scales in Tekirdag Province,Turkey in 2020 by combining the parcel shape index(PSI) with the minimum bounding geometry index(MBG) to improve parcel scores.Hot-spot zones of the highly irregular and near optimum parcels were also determined using Getis-Ord G_(i)^(*) statistic.The parcel degrees were classified into four categories,namely highly irregular,irregular,regular and near optimum.The obtained unweighted scores of the parameters exhibit deviations from the expected values.After weighting by pairwise comparison,the values approached ideal scores.Among 346 740 parcels,53% were highly irregular and irregular and 47% were regular and near optimum shapes after weighting whereas these were 70% and 30%,respectively before weighting.The average parcel degree of 63 rural counties was regular while the average parcel degree of the remaining 264 rural counties was irregular.The combined use of PSI and MBG index improved the correctness of the parcel shape score.It could be suggested to use as a tool in land consolidation prioritization.
文摘Pore water pressure fluctuations are an inherent phenomenon during the consolidation process of clayey foundations, and understanding its mechanism is crucial for comprehending the consolidation process and addressing issues such as drainage blockage during consolidation. This study investigates the consolidation behavior of clay, particularly focusing on pore water pressure fluctuations during the consolidation process of dredged marine sedimentary mud from Daya Bay, Guangdong Province. Given the prevalent use of clay in large-scale construction projects in southern China, understanding the factors influencing pore water pressure is crucial for optimizing consolidation times and improving construction efficacy. Using a custom vacuum preloading model, the research explores the impact of sodium hydroxide on the bound water content and its subsequent effects on pore water pressure dynamics. Experimental findings reveal a distinct inflection point in pore water pressure dissipation, suggesting that particle migration and bound water interactions contribute to the observed fluctuations. These results provide valuable insights for enhancing engineering applications in clay consolidation and mitigating drainage issues, ultimately informing construction practices and reducing project timelines.
基金supported by the Innovation Capability Support Program of Shaanxi Province,China(2023-CX-RKX-102)the Key Research and Development Program of Shaanxi Province,China(2022FP-34)+1 种基金the Open Foundation of the Key Laboratory of Natural Resource Coupling Process and Effects(2023KFKTB008)the Open Fund of Shaanxi Key Laboratory of Land Consolidation,China(300102352502).
文摘Studying the spatiotemporal variations in ecosystem services and their interrelationships on the Loess Plateau against the background of the gully control and land consolidation(GCLC)project has significant implications for ecological protection and quality development of the Yellow River Basin.Therefore,in this study,we took Yan'an City,Shaanxi Province of China,as the study area,selected four typical ecosystem services,including soil conservation service,water yield service,carbon storage service,and habitat quality service,and quantitatively evaluated the spatiotemporal variation characteristics and trade-offs and synergies of ecosystem services from 2010 to 2018 using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.We also analysed the relationship between the GCLC project and regional ecosystem service changes in various regions(including 1 city,2 districts,and 10 counties)of Yan'an City and proposed a coordinated development strategy between the GCLC project and the ecological environment.The results showed that,from 2010 to 2018,soil conservation service decreased by 7.76%,while the other three ecosystem services changed relatively little,with water yield service increasing by 0.56% and carbon storage service and habitat quality service decreasing by 0.16% and 0.14%,respectively.The ecological environment of Yan'an City developed in a balanced way between 2010 and 2018,and the four ecosystem services showed synergistic relationships,among which the synergistic relationships between soil conservation service and water yield service and between carbon storage service and habitat quality service were significant.The GCLC project had a negative impact on the ecosystem services of Yan'an City,and the impact on carbon storage service was more significant.This study provides a theoretical basis for the scientific evaluation of the ecological benefits of the GCLC project and the realization of a win-win situation between food security and ecological security.
