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Marginal Expansion Planning of Infrastructure at a Container Terminal
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作者 Keng Bin Loke Ab. Saman Abd. Kader +2 位作者 Mohd. Zamani Ahmad Saharuddin Abdul Hamid Mohamad Rosni Othman 《Open Journal of Marine Science》 2015年第1期99-107,共9页
Globalization push container terminal grown rapidly in decade. To fulfill the future traffic requirement, this study highlights marginal expansion planning of infrastructure in a container terminal. By using marginal ... Globalization push container terminal grown rapidly in decade. To fulfill the future traffic requirement, this study highlights marginal expansion planning of infrastructure in a container terminal. By using marginal approach, the expansion plan can be determine correctly and economically stage by stage. A mathematical model has generated to calculate the expansion size, expansion time, interval of expansion, expansion cost, and significant of expansion for each infrastructure respectively. It recommended determining the expansion plan for each infrastructure respectively. This is because one of the infrastructures needs to be expanding but the other may not. The generated model was verified with others model and validated with case study to investigate the practicability of the model. The model serves as expansion decision making tools to assist port expansion planners. 展开更多
关键词 INFRASTRUCTURE marginal Approach expansion PLAN MATHEMATICAL Model expansion SIZE expansion Time
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Semi-analytical solution for drained expansion analysis of a hollow cylinder of critical state soils 被引量:1
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作者 He Yang Jialiang Zhang +1 位作者 Haisui Yu Peizhi Zhuang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2326-2340,共15页
The expansion of a thick-walled hollow cylinder in soil is of non-self-similar nature that the stress/deformation paths are not the same for different soil material points.As a result,this problem cannot be solved by ... The expansion of a thick-walled hollow cylinder in soil is of non-self-similar nature that the stress/deformation paths are not the same for different soil material points.As a result,this problem cannot be solved by the common self-similar-based similarity techniques.This paper proposes a novel,exact solution for rigorous drained expansion analysis of a hollow cylinder of critical state soils.Considering stress-dependent elastic moduli of soils,new analytical stress and displacement solutions for the nonself-similar problem are developed taking the small strain assumption in the elastic zone.In the plastic zone,the cavity expansion response is formulated into a set of first-order partial differential equations(PDEs)with the combination use of Eulerian and Lagrangian descriptions,and a novel solution algorithm is developed to efficiently solve this complex boundary value problem.The solution is presented in a general form and thus can be useful for a wide range of soils.With the new solution,the non-self-similar nature induced by the finite outer boundary is clearly demonstrated and highlighted,which is found to be greatly different to the behaviour of cavity expansion in infinite soil mass.The present solution may serve as a benchmark for verifying the performance of advanced numerical techniques with critical state soil models and be used to capture the finite boundary effect for pressuremeter tests in small-sized calibration chambers. 展开更多
关键词 Cavity expansion Drained analysis Boundary effect Critical state soil Non-self-similar Eulerian-Lagrangian approach
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Swelling pressure evolution characterization of strong expansive soil considering the influence of reserved expansion deformation
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作者 LI Tianguo KONG Lingwei +1 位作者 GUO Aiguo YAN Junbiao 《Journal of Mountain Science》 SCIE CSCD 2024年第1期252-270,共19页
Numerous engineering cases have demonstrated that the expansive soil channel slope remains susceptible to damage with the implementation of a rigid or closed protective structure. It is common for the protective struc... Numerous engineering cases have demonstrated that the expansive soil channel slope remains susceptible to damage with the implementation of a rigid or closed protective structure. It is common for the protective structure to experience bulging failure due to excessive swelling pressure. To investigate the swelling pressure properties of expansive soil, the constant volume test was employed to study the influence of water content and reserved expansion deformation on the characteristics of swelling pressure in strong expansive soils, and also to explore the evolution mechanism of the swelling pressure. The findings demonstrate that the swelling pressure-time curve can be classified into swelling pressure-time softening and swelling pressure-time stability type. The swelling pressuretime curve of the specimen with low water content is the swelling pressure-time softening type, and the softening level will be weakened with increasing reserved expansion deformation. Besides, the maximum swelling pressure Psmax decreases with increasing water content and reserved expansion deformation, especially for expansion ratio η from 24% to 37%. The reserved deformation has little effect on reducing Psmax when it is beyond 7% of the expansion rate. The specimen with low water content has a more homogeneous structure due to the significant expansion-filling effect, and the fracture and reorganization of the aggregates in the specimens with low water content cause the swelling pressure-time softening behavior. In addition, the proposed swelling pressure-time curve prediction model has a good prediction on the test results. If necessary, a deformation space of about 7% expansion rate is recommended to be reserved in the engineering to reduce the swelling pressure except for keeping a stable water content. 展开更多
关键词 Expansive soil Swelling pressure Reserved expansion deformation Water content
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Marginal zone lymphoma with severe rashes: A case report
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作者 Si-Jun Bai Ye Geng +7 位作者 Yi-Nan Gao Cai-Xia Zhang Qian Mi Chen Zhang Jia-Ling Yang Si-Jie He Zhen-YingYan Jian-Xia He 《World Journal of Clinical Cases》 SCIE 2024年第3期565-574,共10页
BACKGROUND Marginal zone lymphoma(MZL)is an indolent subtype of non-Hodgkin lymphoma(NHL),which is rare clinically with severe rashes as the initial symptom.CASE SUMMARY This study reports a case of MZL with generaliz... BACKGROUND Marginal zone lymphoma(MZL)is an indolent subtype of non-Hodgkin lymphoma(NHL),which is rare clinically with severe rashes as the initial symptom.CASE SUMMARY This study reports a case of MZL with generalized skin rashes accompanied by pruritus and purulent discharge.First-line treatment with rituximab combined with zanubrutinib had poor effects.However,after switching to obinutuzumab combined with zanubrutinib,the case was alleviated,and the rashes disappeared.CONCLUSION For patients with advanced stage MZL not benefiting from type I anti-CD20 monoclonal antibody(mAb)combination therapy,switching to a type II anti-CD20 mAb combination regimen may be considered.This approach may provide a new perspective in the treatment of MZL. 展开更多
关键词 marginal zone lymphoma Mucosa-associated lymphoid tissue Extranodal marginal zone lymphoma Primary cutaneous marginal zone lymphoma Rituximab Obinutuzumab Zanubrutinib Case report
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The largest CPIES array in the marginal sea:abundant dynamics in the northeast South China Sea
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作者 Hua Zheng Xiao-Hua Zhu +4 位作者 Min Wang Ruixiang Zhao Chuanzheng Zhang Feng Nan Fei Yu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第1期135-137,共3页
The South China Sea(SCS)is a marginal sea connecting the Pacific and Indian oceans and has gained much attention in recent decades.The dynamics in the northeast SCS are considerably influenced by topography,monsoons,t... The South China Sea(SCS)is a marginal sea connecting the Pacific and Indian oceans and has gained much attention in recent decades.The dynamics in the northeast SCS are considerably influenced by topography,monsoons,tropical cyclones,the Kuroshio intrusion,and water exchange through the Luzon Strait(LS). 展开更多
关键词 NORTHEAST marginal abundant
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Expansion of human umbilical cord derived mesenchymal stem cells in regenerative medicine
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作者 Shafiqa Naeem Rajput Bushra Kiran Naeem +2 位作者 Anwar Ali Asmat Salim Irfan Khan 《World Journal of Stem Cells》 SCIE 2024年第4期410-433,共24页
BACKGROUND Stem cells are undifferentiated cells that possess the potential for self-renewal with the capacity to differentiate into multiple lineages.In humans,their limited numbers pose a challenge in fulfilling the... BACKGROUND Stem cells are undifferentiated cells that possess the potential for self-renewal with the capacity to differentiate into multiple lineages.In humans,their limited numbers pose a challenge in fulfilling the necessary demands for the regeneration and repair of damaged tissues or organs.Studies suggested that mesenchymal stem cells(MSCs),necessary for repair and regeneration via transplantation,require doses ranging from 10 to 400 million cells.Furthermore,the limited expansion of MSCs restricts their therapeutic application.AIM To optimize a novel protocol to achieve qualitative and quantitative expansion of MSCs to reach the targeted number of cells for cellular transplantation and minimize the limitations in stem cell therapy protocols.METHODS Human umbilical cord(hUC)tissue derived MSCs were obtained and re-cultured.These cultured cells were subjected to the following evaluation pro-cedures:Immunophenotyping,immunocytochemical staining,trilineage differentiation,population doubling time and number,gene expression markers for proliferation,cell cycle progression,senescence-associatedβ-galactosidase assay,human telomerase reverse transcriptase(hTERT)expression,mycoplasma,cytomegalovirus and endotoxin detection.RESULTS Analysis of pluripotent gene markers Oct4,Sox2,and Nanog in recultured hUC-MSC revealed no significant differences.The immunophenotypic markers CD90,CD73,CD105,CD44,vimentin,CD29,Stro-1,and Lin28 were positively expressed by these recultured expanded MSCs,and were found negative for CD34,CD11b,CD19,CD45,and HLA-DR.The recultured hUC-MSC population continued to expand through passage 15.Proliferative gene expression of Pax6,BMP2,and TGFb1 showed no significant variation between recultured hUC-MSC groups.Nevertheless,a significant increase(P<0.001)in the mitotic phase of the cell cycle was observed in recultured hUC-MSCs.Cellular senescence markers(hTERT expression andβ-galactosidase activity)did not show any negative effect on recultured hUC-MSCs.Additionally,quality control assessments consistently confirmed the absence of mycoplasma,cytomegalovirus,and endotoxin contamination.CONCLUSION This study proposes the development of a novel protocol for efficiently expanding stem cell population.This would address the growing demand for larger stem cell doses needed for cellular transplantation and will significantly improve the feasibility of stem cell based therapies. 展开更多
关键词 Human umbilical cord Mesenchymal stem cells expansion Cell proliferation In vitro expansion SENESCENCE
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Significant lake expansion has accelerated permafrost degradation on the Qinghai-Tibet Plateau
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作者 LI Qingpeng LIU Wenhui +6 位作者 LIU Hairui ZHOU Guanghao SONG Xianteng LI Qing LUO Bingnan SONG Bangxu ZHANG Qi 《Journal of Mountain Science》 SCIE CSCD 2024年第1期68-83,共16页
In recent years, lakes on the Qinghai-Tibet Plateau have become more responsive to climate change. In September 2011, Zonag Lake in Hoh Xil experienced sudden drainage, the water eventually flowed into Yanhu Lake, whi... In recent years, lakes on the Qinghai-Tibet Plateau have become more responsive to climate change. In September 2011, Zonag Lake in Hoh Xil experienced sudden drainage, the water eventually flowed into Yanhu Lake, which caused Yanhu Lake to continue to expand. The potential collapse of Yanhu Lake could directly threaten the operational safety of the adjacent Qinghai-Tibet Highway, Qinghai-Tibet Railway. To explore the implications of expanding lakes on the surrounding permafrost, we selected Hoh Xil Yanhu Lake on the Qinghai-Tibet Plateau to study the effect of lake expansion on permafrost degradation. The permafrost degradation in the Yanhu Lake basin from October 2017 to December 2022 was inverted using Sentinel-1 satellite image data and small baseline subset interferometry synthetic aperture radar(SBAS-In SAR) technology. Additionally, permafrost degradation from February 2007 and February 2010 was analyzed using advanced land observing satellite phased array-type L-band synthetic aperture radar(ALOS PALSAR) satellite images and differential interferometric synthetic aperture radar(D-In SAR) technique. The results showed that the permafrost around Yanhu Lake experienced accelerated degradation. Prior to the expansion of Yanhu Lake, the average annual deformation rate along the line of sight(LOS) direction was 6.7 mm/yr. After the expansion, the rate increased to 20.9 mm/yr. The integration of spatial-temporal distribution maps of surface subsidence, Wudaoliang borehole geothermal data, meteorological data, Yanhu Lake surface area changes, and water level changes supports the assertion that the intensified permafrost degradation could be attributed to lake expansion rather than the rising air temperature. Furthermore, permafrost degradation around Yanhu Lake could impact vital infrastructure such as the adjacent Qinghai-Tibet Highway and Qinghai-Tibet Railway. 展开更多
关键词 Lake expansion SBAS-InSAR D-INSAR Permafrost deformation Qinghai-Tibet Plateau
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To Uplift the Profitability of Marginal Lands by Cassava Cultivation
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作者 Zusheng Wei Jianqi Huang +1 位作者 Xiujuan Yang Haitian Fu 《Agricultural Sciences》 2024年第11期1163-1178,共16页
Expanding the utilization of marginal land resources in rural areas is regarded as a significant supplement for the sustainable development of modern agriculture for its yield, economic and ecological good. Marginal a... Expanding the utilization of marginal land resources in rural areas is regarded as a significant supplement for the sustainable development of modern agriculture for its yield, economic and ecological good. Marginal areas, due to their natural limitations, are only productive for energy crops with strong resistance and tolerance. Cassava, in its longstanding cultivation practices, has marked its adaptability in tropical and subtropical regions. Farmers are allowed to improve reclaimed soils’ fertility, while plants’ canopy coverage could reduce soil erosion. Besides, cassava tubers to be produced as food or fodder can be counted as soil productivity. Breeding advanced cassava varieties on marginal land under proper intensification management and facilitating policies can indeed increase farmers’ income. Some of the projects implemented outside of China speak quite well on that. Additionally, intercropping modes for cassava bring higher incomes than monocropping mode, which simultaneously improves the ecosystem structure and soil conditions. The interspecific cooperation brought by the intercropping pattern has its buffering function and antagonistic effects to counter against plant diseases, pest attacks and weed infestations. It performs as a natural alternative for pesticides and fertilizers with minimal inputs and safe and productive outputs. Although a complete cassava industrial chain has been formed nationwide, there are still challenges like the inadequate use of marginal areas and risks triggered by unfavorable climate, changeable commodity markets, and the composition of the labor force. However, there will still be ample room for further growth of cassava, for recent years have witnessed the acceleration in the circulation of rural land management rights and the stratification of Chinese farmers, which gives an impetus to household management’s dominance as well as the improvements of rural social welfare systems for the overall agricultural efficiency. 展开更多
关键词 marginal Land Economic Profits Ecological Benefits PLANTING CASSAVA
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Deep Expansion of the Object Scope of Contemporary Female Literature Research --On. the "Marginalized" Female Creation in Late Qing Dynasty and Republican Period
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作者 Zhao Huifang 《学术界》 CSSCI 北大核心 2016年第3期269-274,共6页
If we take Chinese modern literary history( female) as the"center",in which the female creation is very limited,a large amount of female compositions in late Qing Dynasty and R epublican period were "ma... If we take Chinese modern literary history( female) as the"center",in which the female creation is very limited,a large amount of female compositions in late Qing Dynasty and R epublican period were "marginalized",even in the "hidden "state. These "marginalized"female writings,not only are in a large number,but also constitute the foundation of Chinese modern female literature creation,the significance and value cannot be ignored. To seek the strategy and approach for the research on the "marginalized"female creation in late Qing Dynasty and R epublican period,helps to deeply discuss the possibility to expand the object scope of female literature research,to find a newgrowing point of female literature research,and form conversation between female literary history writing and current theory and practice of the"R ewriting Literary History". 展开更多
关键词 文学创作 边缘化 女性 民国 晚清 增长点 中国 作品
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Bendamustine and rituximab as frontline therapy in extranodal marginal zone lymphoma:a single-institution experience
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作者 CONSTANTINE N.LOGOTHETIS NATHAN P.HORVAT +8 位作者 TONY KURIAN CELESTE BELLO JULIO CHAVEZ LEIDY ISENALUMHE BIJAL SHAH LUBOMIR SOKOL HAYDER SAEED JAVIER PINILLA SAMEH GABALLA 《Oncology Research》 SCIE 2024年第6期1031-1036,共6页
Extranodal marginal zone lymphoma(EMZL)encompasses 70%of cases of marginal zone lymphoma.Frontline bendamustine and rituximab(BR)were derived from trials involving other indolent non-Hodgkin’s lymphomas.Only one tria... Extranodal marginal zone lymphoma(EMZL)encompasses 70%of cases of marginal zone lymphoma.Frontline bendamustine and rituximab(BR)were derived from trials involving other indolent non-Hodgkin’s lymphomas.Only one trial has evaluated frontline BR prospectively in EMZL.This retrospective study reports outcomes among EMZL patients receiving frontline BR.Twenty-five patients were included with a median age of 69 years(40–81).Five(20.0%)patients had stage Ⅰ/Ⅱ disease,and 20(80.0%)had stage Ⅲ/Ⅳ disease.The median number of cycles was 6.0(3.0–6.0).Maintenance rituximab was administered to 10(41.7%)individuals.Overall response rate(ORR)was 100.0%(60.0%complete response,40.0%partial response).Medians of overall survival and progression-free survival were not reached.The estimated 2-year progression-free survival was 85.2%and overall survival was 100.0%.Four(16.6%)patients had infections related to treatment;3(12.0%)transformed to diffuse large B-cell lymphoma;5(20.8%)had a relapse or progression of EMZL;and 3(12.0%)died unrelated to BR.BR is an efficacious and well-tolerated front-line regimen for EMZL with response data consistent with existing literature. 展开更多
关键词 Extranodal marginal zone lymphoma BENDAMUSTINE RITUXIMAB Front-line therapy
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Analysis and Comparison of Slope-cutting Widening Schemes in Highway Reconstruction and Expansion Project Based on MIDAS Software 被引量:1
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作者 Zhiqiang Qiu Yun Shi Lei Jiang 《Journal of Architectural Research and Development》 2024年第2期75-83,共9页
In this paper,the geological condition of the right-side slope of the K114+694–K115+162 section of Yong-tai-wen Expressway is investigated and analyzed with the results showing that the strength of rock mass is the m... In this paper,the geological condition of the right-side slope of the K114+694–K115+162 section of Yong-tai-wen Expressway is investigated and analyzed with the results showing that the strength of rock mass is the main contributor to the stability of the slope.Then,two widening schemes are proposed,which are the steep slope with strong support and the gentle slope with general support schemes.The static/slope module of MIDAS GTS finite element analysis software and the strength reduction method were used to compare the two schemes.The results show that the steep slope with a strong support scheme has obvious advantages in land requisition,environmental protection,and safety and is more suitable for reconstructing and expanding the highway slope. 展开更多
关键词 Highway reconstruction and expansion Slope excavation MIDAS GTS Scheme selection
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Research on the Generation Mechanism and Suppression Method of Aerodynamic Noise in Expansion Cavity Based on Hybrid Method
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作者 Haitao Liu Jiaming Wang +2 位作者 Xiuliang Zhang Yanji Jiang Qian Xiao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2747-2772,共26页
The expansion chamber serves as the primary silencing structure within the exhaust pipeline.However,it can also act as a sound-emitting structure when subjected to airflow.This article presents a hybrid method for num... The expansion chamber serves as the primary silencing structure within the exhaust pipeline.However,it can also act as a sound-emitting structure when subjected to airflow.This article presents a hybrid method for numerically simulating and analyzing the unsteady flow and aerodynamic noise in an expansion chamber under the influence of airflow.A fluid simulation model is established,utilizing the Large Eddy Simulation(LES)method to calculate the unsteady flow within the expansion chamber.The simulation results effectively capture the development and changes of the unsteady flow and vorticity inside the cavity,exhibiting a high level of consistency with experimental observations.To calculate the aerodynamic noise sources within the cavity,the flow field results are integrated using the method of integral interpolation and inserted into the acoustic grid.The acoustic analogy method is then employed to determine the aerodynamic noise sources.An acoustic simulation model is established,and the flow noise source is imported into the sound field grid to calculate the sound pressure at the far-field response point.The calculated sound pressure levels and resonance frequencies show good agreement with the experimental results.To address the issue of airflow regeneration noise within the cavity,perforated tubes are selected as a means of noise suppression.An experimental platformfor airflow regeneration noise is constructed,and experimental samples are processed to analyze and verify the noise suppression effect of perforated tube expansion cavities under different airflow velocities.The research findings indicate that the perforated tube expansion cavity can effectively suppress low-frequency aerodynamic noise within the cavity by impeding the formation of strong shear layers.Moreover,the semi-perforated tube expansion cavity demonstrates the most effective suppression of aerodynamic noise. 展开更多
关键词 expansion cavity aerodynamic noise numerical simulation hybrid method perforated tube
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Study on plasma expansion model of primary discharge on spacecraft solar array
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作者 Dejie WEI Jianwen WU Liying ZHU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第11期87-95,共9页
In the space plasma environment, primary discharge may occur on the solar array and evolve into a destructive sustained arc, which threatens the safe operation of the spacecraft. Based on the plasma expansion fluid th... In the space plasma environment, primary discharge may occur on the solar array and evolve into a destructive sustained arc, which threatens the safe operation of the spacecraft. Based on the plasma expansion fluid theory, a new multicomponent plasma expansion model is proposed in this study, which takes into account the effects of ion species, ion number, initial discharge current, and Low Earth Orbit(LEO) plasma environment. The expansion simulation of single-component and multicomponent ions is carried out respectively, and the variations of plasma number density, expansion distance, and speed during the expansion process are obtained.Compared with the experimental results, the evolution of propagation distance and speed is closed and the error is within a reasonable range, which verifies the validity and rationality of the model. The propagation characteristics of the primary discharge on the solar array surface and the influence of the initial value on the maximum propagation distance and the propagation current peaks are investigated. This study can provide important theoretical support for the propagation and evolution of the primary discharge and the key behavior of the transition to secondary discharge on spacecraft solar array. 展开更多
关键词 primary discharge plasma expansion propagation characteristics spacecraft solar array
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Stochastic programming based coordinated expansion planning of generation,transmission,demand side resources,and energy storage considering the DC transmission system
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作者 Liang Lu Mingkui Wei +4 位作者 Yuxuan Tao Qing Wang Yuxiao Yang Chuan He Haonan Zhang 《Global Energy Interconnection》 EI CSCD 2024年第1期25-37,共13页
With the increasing penetration of wind and solar energies,the accompanying uncertainty that propagates in the system places higher requirements on the expansion planning of power systems.A source-grid-load-storage co... With the increasing penetration of wind and solar energies,the accompanying uncertainty that propagates in the system places higher requirements on the expansion planning of power systems.A source-grid-load-storage coordinated expansion planning model based on stochastic programming was proposed to suppress the impact of wind and solar energy fluctuations.Multiple types of system components,including demand response service entities,converter stations,DC transmission systems,cascade hydropower stations,and other traditional components,have been extensively modeled.Moreover,energy storage systems are considered to improve the accommodation level of renewable energy and alleviate the influence of intermittence.Demand-response service entities from the load side are used to reduce and move the demand during peak load periods.The uncertainties in wind,solar energy,and loads were simulated using stochastic programming.Finally,the effectiveness of the proposed model is verified through numerical simulations. 展开更多
关键词 Hydro-wind-solar complementary expansion planning Demand response Energy storage system Source-network-demand-storage coordination
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The Negative Thermal Expansion Property of NdMnO_(3) Based on Pores Effect and Phase Transition
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作者 李玉成 张扬 +2 位作者 ZHANG Muqun DUAN Rong LIU Xiteng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期39-43,共5页
A novel negative thermal expansion(NTE) material NdMnO_(3) was synthesized by solid-state method at 1 523 K. The crystal structure, phase transition, pores effect and negative expansion properties of NdMnO_(3) were in... A novel negative thermal expansion(NTE) material NdMnO_(3) was synthesized by solid-state method at 1 523 K. The crystal structure, phase transition, pores effect and negative expansion properties of NdMnO_(3) were investigated by variable temperature X-ray diffraction(XRD), scanning electron microscope(SEM) and variable temperature Raman spectra. The compound exhibits NTE properties in the orderly O' phase crystal structure. When the temperature is from 293 to 759 K, the ceramic NdMnO_(3) shows negative thermal expansion of-4.7×10^(-6)/K. As temperature increases, the ceramic NdMnO_(3) presents NTE property range from 759 to 1 007 K. The average linear expansion coefficient is-18.88×10^(-6)/K. The physical mechanism of NTE is discussed and clarified through experiments. 展开更多
关键词 negative thermal expansion NdMnO_(3) pores effect phase transition
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Deformation mechanisms and microstructural characteristics of AZ61 magnesium alloys processed by a continuous expansion extrusion approach
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作者 Yang Mo Fulin Jiang +4 位作者 Hang Xu Jie Tang Dingfa Fu Hui Zhang Jie Teng 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第7期2826-2846,共21页
The unique continuous extrusion-based severe plastic deformation approaches were proposed recently to process high-performance magnesium (Mg) alloys,while the in-depth deformation mechanisms under such complicated the... The unique continuous extrusion-based severe plastic deformation approaches were proposed recently to process high-performance magnesium (Mg) alloys,while the in-depth deformation mechanisms under such complicated thermomechanical conditions were not well understood In the present work,the fundamental deformation behaviors of AZ61 Mg alloy from 25 to 400°C were firstly examined under uniaxial compression deformation.Then the deformation mechanisms and microstructural characteristics of AZ61 Mg alloy during continuous expansion extrusion forming (CEEF) were systematically investigated by microstructural observations,finite element and cellular automata simulations The results showed that the continuous evolutions of temperature,larger strain level and complex stress state with strain rate range of 0~5.98 s-1during CEEF brought the distinctive dynamic recrystallization behaviors and texture development in AZ61 Mg alloy,which were different to that of uniaxial compression deformation.In details,a remarkable grain refinement was achieved via CEEF processing due to the simultaneous actions of continuous dynamic recrystallization (CDRX) and discontinuous dynamic recrystallization (DDRX).Gradually enhanced CDRX were observed from center to edge region,which had significant effects on the texture distribution and texture strength.The c-axis of most grains rotated under distinctive shear strain following parabolic metal flow,resulting in stable fiber texture.In addition,the evolution of the internal texture of the alloy led to an obvious increase in the Schmid factor for the activation of basal(c+a)slip system.©2022 Chongqing University.Publishing services provided by Elsevier B.V.on behalf of Ke Ai Communications Co.Ltd. 展开更多
关键词 Magnesium alloy Deformation Continuous expansion extrusion forming Microstructure Finite element simulation
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Depositional model of the Member Deng-2 marginal microbial mound-bank complex of the Dengying Formation in the southwestern Sichuan Basin, SW China: Implications for the Ediacaran microbial mound construction and hydrocarbon exploration
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作者 Jin-Min Song Xin Jin +10 位作者 Zhong Luo Shu-Gen Liu Shao-Bo Liu Xing-Zhi Ma Zhi-Wu Li Xue-Song Lu Ling-Li Zhao Ke-Ran Li Jia-Xin Ren Li-Zhou Tian Hao-Shuang Deng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期806-822,共17页
Recent advances in hydrocarbon exploration have been made in the Member Deng-2 marginal microbial mound-bank complex reservoirs of the Dengying Formation in the western Sichuan Basin, SW China,where the depositional p... Recent advances in hydrocarbon exploration have been made in the Member Deng-2 marginal microbial mound-bank complex reservoirs of the Dengying Formation in the western Sichuan Basin, SW China,where the depositional process is regarded confusing. The microfacies, construction types, and depositional model of the Member Deng-2 marginal microbial mound-bank complex have been investigated using unmanned aerial vehicle photography, outcrop section investigation, thin section identification,and seismic reflections in the southwestern Sichuan Basin. The microbialite lithologic textures in this region include thrombolite, dendrolite, stromatolite, fenestral stromatolite, spongiostromata stone,oncolite, aggregated grainstone, and botryoidal grapestone. Based on the comprehensive analysis of“depositional fabrics-lithology-microfacies”, an association between a fore mound, mound framework,and back mound subfacies has been proposed based on water depth, current direction, energy level and lithologic assemblages. The microfacies of the mound base, mound core, mound flank, mound cap, and mound flat could be recognized among the mound framework subfacies. Two construction types of marginal microbial mound-bank complex have been determined based on deposition location, mound scale, migration direction, and sedimentary facies association. Type Jinkouhe microbial mound constructions(TJMMCs) develop along the windward margin owing to their proximity to the seaward subfacies fore mound, with a northeastwardly migrated microbial mound on top of the mud mound,exhibiting the characteristics of large-sized mounds and small-sized banks in the surrounding area. Type E'bian microbial mound constructions(TEMMCs) primarily occur on the leeward margin, resulting from the presence of onshore back mound subfacies, with the smaller southwestward migrated microbial mounds existing on a thicker microbial flat. The platform margin microbial mound depositional model can be correlated with certain lateral comparison profile and seismic reflection structures in the 2D seismic section, which can provide references for future worldwide exploration. Microbial mounds with larger buildups and thicker vertical reservoirs are typically targeted on the windward margin, while small-sized microbial mounds and flats with better lateral connections are typically focused on the leeward margin. 展开更多
关键词 Sichuan Basin The Member Deng-2 marginal microbial mound-bank complex Depositional model Exploration implications
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An Interpolation Method for Karhunen-Loève Expansion of Random Field Discretization
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作者 Zi Han Zhentian Huang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期245-272,共28页
In the context of global mean square error concerning the number of random variables in the representation,the Karhunen–Loève(KL)expansion is the optimal series expansion method for random field discretization.T... In the context of global mean square error concerning the number of random variables in the representation,the Karhunen–Loève(KL)expansion is the optimal series expansion method for random field discretization.The computational efficiency and accuracy of the KL expansion are contingent upon the accurate resolution of the Fredholm integral eigenvalue problem(IEVP).The paper proposes an interpolation method based on different interpolation basis functions such as moving least squares(MLS),least squares(LS),and finite element method(FEM)to solve the IEVP.Compared with the Galerkin method based on finite element or Legendre polynomials,the main advantage of the interpolation method is that,in the calculation of eigenvalues and eigenfunctions in one-dimensional random fields,the integral matrix containing covariance function only requires a single integral,which is less than a two-folded integral by the Galerkin method.The effectiveness and computational efficiency of the proposed interpolation method are verified through various one-dimensional examples.Furthermore,based on theKL expansion and polynomial chaos expansion,the stochastic analysis of two-dimensional regular and irregular domains is conducted,and the basis function of the extended finite element method(XFEM)is introduced as the interpolation basis function in two-dimensional irregular domains to solve the IEVP. 展开更多
关键词 Random field discretization KL expansion IEVP MLS FEM stochastic analysis
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An agent-based model of agricultural land expansion in the mountain forest of Timor Island,Indonesia
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作者 PUJIONO Eko SADONO Ronggo +12 位作者 IMRON Muhammad Ali SUTOMO JANUAR Hedi Indra KUSWANDI Relawan KURNIAWAN Hery HADI Etik Erna Wati SAPUTRA Muhammad Hadi HIDAYAH Izhamil HUMAIDA Nida SUKMAWATI Jalma Giring HADIYAN Yayan NUGROHO Agung Wahyu HANI Aditya 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2263-2282,共20页
The Mutis-Timau Forest Complex,located on Timor Island,Indonesia,is a mountainous tropical forest area that gradually decreases due to deforestation and forest degradation.Previous modelling studies based on patterns ... The Mutis-Timau Forest Complex,located on Timor Island,Indonesia,is a mountainous tropical forest area that gradually decreases due to deforestation and forest degradation.Previous modelling studies based on patterns indicate that deforestation primarily occurs at lower elevations and near the boundaries of forests and settlements,often associated with shifting cultivation by local farmers.This study adopts a process-based modelling approach,specifically the agent-based model,to simulate land changes,particularly farmers'expansion of agricultural land around the Mutis mountain forest.The underlying concept of this agent-based approach is the interaction between the human and environmental systems.Farmers,representing the human system,interact with the land,which represents the environmental system,through land use decision-making mechanisms.The research was conducted in the Community Forest of the Timor Tengah Utara District,one of the sites within the Mutis-Timau Forest Complex with the highest deforestation rate.Land use change simulations were performed using agent-based modelling from 1999 to 2030,considering the socio-economic conditions of farmers,spatial preferences,land use decisions,and natural transitions.The results revealed that the agricultural area increased by 14%under the Business as Usual scenario and 5%under the Reducing Emission from Deforestation and Forest Degradation scenario,compared to the initial agricultural area of 245 hectares.The probability of farmers deciding to extend agricultural activities was positively associated with the number of livestock maintained by farmers and the size of the village area.Conversely,the likelihood of farmers opting for agricultural extensification decreased with an increase in the area of private land and the farmer's age.These findings are crucial for the managers of the Mutis-Timau Forest Complex and other relevant stakeholders,as they aid in arranging actions to combat deforestation,designing proper forest-related policies,and providing support for initiatives such as reducing emissions from deforestation and forest degradation programs or further incentive schemes. 展开更多
关键词 Agricultural land expansion Simulation Agent-based model FARMER DEFORESTATION Mountainous tropical forest
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Higher-order expansions of powered extremes of logarithmic general error distribution
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作者 TAN Xiao-feng LI Li-hui 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期47-54,共8页
In this paper,Let M_(n)denote the maximum of logarithmic general error distribution with parameter v≥1.Higher-order expansions for distributions of powered extremes M_(n)^(p)are derived under an optimal choice of nor... In this paper,Let M_(n)denote the maximum of logarithmic general error distribution with parameter v≥1.Higher-order expansions for distributions of powered extremes M_(n)^(p)are derived under an optimal choice of normalizing constants.It is shown that M_(n)^(p),when v=1,converges to the Frechet extreme value distribution at the rate of 1/n,and if v>1 then M_(n)^(p)converges to the Gumbel extreme value distribution at the rate of(loglogn)^(2)=(log n)^(1-1/v). 展开更多
关键词 logarithmic general error distribution convergence rate higher-order expansion powered ex-treme
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