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81.
Shang Yonghui Nguyen Hoang Bui Xuan-Nam Tran Quang-Hieu Moayedi Hossein 《Natural Resources Research》2020,29(2):723-737
Natural Resources Research - The primary purpose of this study was to develop a novel hybrid artificial intelligence model, with a robust performance, to predict ground vibration induced by bench... 相似文献
82.
Hoang Tung Do Huyen Alleman James Cetin Bora Dayioglu Asli Y. 《Acta Geotechnica》2023,18(2):1073-1092
Acta Geotechnica - This paper addresses a soil bio-stabilization technique using bacterial enzyme-induced calcium carbonate precipitation (BEICP) as an alternative to previous conventional methods... 相似文献
83.
ABSTRACTThis paper explores dynamics of conflict over forests in Vietnam, as the country lays the groundwork for Reducing Emissions from Deforestation and Forest Degradation (REDD+). Drawing on a case study in Lam Dong province and applying an environmental justice lens, we examine how various social actors assert claims over forests and how these claims invoke different notions of justice, authority and identity. Our analysis highlights that the development and implementation of the project has generated renewed competing claims and conflicts over forests among social actors. Underlying these conflicts there are incompatible notions of justice and associated rights, which lead different actors to accord legitimacy variously to the global norms brought about by REDD+, the customary resource practices of indigenous people, or to the state’s laws. We show that the negotiations over forests in REDD+ reflect the influence of the specific historical and political-economic settings in which REDD+ activities take place, including pre-existing conflicts over forests and power relations underpinning forest management. From a policy perspective, our research suggests that any attempts to introduce simplified and uniform regulations for forest governance in REDD+ should be avoided, since local institutions and conceptions of justice will significantly influence what is regarded as legitimate policy and can thus be endorsed as inspiration for sustainable forest governance.Key policy insights
REDD+ in Vietnam has spurred contestations over who is legitimately entitled to govern and manage forests.
Claims and conflicts over forests can be explained by incompatible and distinct notions of justice, authority and identity.
Contestations over justice pose radical challenges to any global and national efforts that attempt to implement simplified rules and ideas for forest based-climate change mitigation.
Attention to justice, especially to compatibility and differences in ideas about justice, is crucial for sustainable forest governance.
84.
自然条件下的河流水质模型在高强度人类活动影响的城市河流应用中存在局限性,构建耦合人类活动影响的水质模型是识别城市河流水质变化的关键。针对永定河北京段自然水循环与再生水、循环管线回水及外调水等人类活动相互作用的特点,构建了基于分布式时变增益水文模型与一维稳态的水质过程耦合的模型,分析了不同调水情景下永定河北京段水质变化过程。应用表明该模型在永定河北京段具有良好的适用性,不仅能描述过去天然条件、现状条件下水质过程,同时能应用于未来规划情景下的水质预测,同时表明外调水工程对永定河北京段的水量水质有显著的改善作用。 相似文献
85.
Lam Van Nguyen Ngoc Kim Nguyen Hoan Van Hoang Tuan Quang Tran Nga Trong Vu 《Environmental Earth Sciences》2013,70(2):501-510
The groundwater in the karst region of northeastern Vietnam is found in various structural zones such as the Ha Lang, Song Hien, Hon Gai, Song Lo, Song Gam, and Hoang Lien Son Zones, etc. Results from this study show that groundwater in this region is at different depths: ~120 m deep at Quang Ninh, ~100 m at Lang Son, ~80 m at Cao Bang (The most water-abundant depth observed at Cao Bang varies from 40 to 45 m) while it varies from 18–25 to 80 m deep at Quan Ba (Ha Giang), especially at Meo Vac (Ha Giang), where groundwater is observed at 700–800 m deep (equivalent to local base level of the Nho Que River). Overall, groundwater in the region is fresh with total minerals varying from 250 to 400 mg/l; except for the coastal area of Quang Ninh, where groundwater is characterized by much higher total minerals (M = 3–18 g/l) due to the mixing with the saline sea water. The chemistry of water in the region demonstrates that the water is mainly bicarbonate with a [HCO3 ?] concentration varying from 150 to 265 mg/l, pH is of 6.5–8.1, and its hardness is of 3.7–6.0 meq/l. 相似文献
86.
Phan Trong Trinh Hoang Quang Vinh Nguyen Van Huong Ngo Van Liem 《Central European Journal of Geosciences》2013,5(2):223-235
Based on remote sensing, geological data, geomorphologic analysis, and field observations, we determine the fault system which is a potential source of earthquakes in Hoa-Binh reservoir. It is the sub-meridian fault system composed of fault segments located in the central part of the eastern and western flanks of the Quaternary Hoa-Binh Graben: the Hoa-Binh 1 fault is east-dipping (75–80°), N-S trending, 4 km long, situated in the west of the Hoa-Binh Graben, and the Hoa-Binh 2 is a west-dipping (75–80°), N-S trending; 8.4 km long fault, situated in the east of the Hoa-Binh Graben. The slip rate of normal fault in Hoa-Binh hydropower dam was estimated at 0.3–1.1 mm/yr. The Maximum Credible Earthquake (MCE) and Peak Ground Acceleration (PGA) in the Hoa-Binh hydropower dam have been assessed. The estimated MCE of HB.1 and HB.2 is 5.6 and 6.1 respectively, and the maximum PGA at Hoa-Binh dam is 0.30 g and 0.40 g, respectively. The assessment of seismic hazard in Hoa-Binh reservoir is a typical example of seismic hazards of a large dam constructed in an area of low seismicity and lack of law of seismic attenuation. 相似文献
87.
Origin and extent of fresh groundwater, salty paleowaters and recent saltwater intrusions in Red River flood plain aquifers, Vietnam 总被引:1,自引:0,他引:1
Luu T. Tran Flemming Larsen Nhan Q. Pham Anders V. Christiansen Nghi Tran Hung V. Vu Long V. Tran Hoan V. Hoang Klaus Hinsby 《Hydrogeology Journal》2012,20(7):1295-1313
A model has been established on the origin and extent of fresh groundwater, salty paleowaters and saltwater from recent seawater intrusions in the Red River flood plain in Vietnam. This was done with geological observations, geophysical borehole logging and transient electromagnetic methods. Salt paleowater is present up to 50–75?km from the coastline, with occurrence controlled by the Holocene transgression. A density-driven leaching of salty porewater has occurred from high-permeability Holocene sediments into underlying Pleistocene deposits, whereas diffusion has dominated in low-permeability layers. In the Pleistocene aquifer, the highest content of dissolved solids is found below two intrinsic valleys with Holocene marine sediments and along the coastline. Recent intrusion of saltwater from the South China Sea is observed in shallow groundwater 35?km inland, probably a result of transport of salty water inland in rivers or leaching of paleowaters from very young near-coast marine sediments. The observed inverted salinity profile, with high saline water overlying fresher groundwater, has been formed due to the global eustatic sea-level changes during the last 8,000–9,000?years. The proposed model may therefore be applicable to other coastal aquifers, with a proper incorporation of the local geological environments. 相似文献
88.
K. Issautier M. Moncuquet N. Meyer-Vernet S. Hoang R. Manning 《Astrophysics and Space Science》2001,277(1-2):309-311
We present the method of plasma diagnostics by quasi-thermal noise spectroscopy and show examples of application in the solar
wind and the Earth's plasmasphere. Using only an electric antenna and a radio receiver, diagnostics of various space environments
(magnetized or not) can be obtained in situ. Because of its accuracy, this technique can be used to cross-check other plasma sensors.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
89.
Dieu Tien Bui Binh Thai Pham Quoc Phi Nguyen Nhat-Duc Hoang 《International Journal of Digital Earth》2016,9(11):1077-1097
This study represents a hybrid intelligence approach based on the differential evolution optimization and Least-Squares Support Vector Machines for shallow landslide prediction, named as DE–LSSVMSLP. The LSSVM is used to establish a landslide prediction model whereas the DE is adopted to search the optimal tuning parameters of the LSSVM model. In this research, a GIS database with 129 historical landslide records in the Quy Hop area (Central Vietnam) has been collected to establish the hybrid model. The receiver operating characteristic (ROC) curve and area under the curve (AUC) were used to assess the performance of the newly constructed model. Experimental results show that the proposed model has high performances with approximately 82% of AUCs on both training and validating datasets. The model’s results were compared with those obtained from other methods, Support Vector Machines, Multilayer Perceptron Neural Networks, and J48 Decision Trees. The result comparison demonstrates that the DE–LSSVMSLP deems best suited for the dataset at hand; therefore, the proposed model can be a promising tool for spatial prediction of rainfall-induced shallow landslides for the study area. 相似文献
90.
BUI Hoang B NGO Xuan Thanh Yungoo SONG Tetsumaru ITAYA Koshi YAGI KHUONG The Hung NGUYEN Tien Dung 《《地质学报》英文版》2016,90(5):1653-1663
Constraining the timing of fault zone formation is fundamentally important in terms of geotectonics to understand structural evolution and brittle fault processes.This paper presents the first authigenic illite K-Ar age data from fault gouge samples collected from the Red River Shear Zone at Lao Cai province,Vietnam.The fault gouge samples were separated into three grain-size fractions(0.1 μm,0.1-0.4 μm and 0.4-1.0 μm).The results show that the K-Ar age values decrease from coarser to finer grain fractions(24.1 to 19.2 Ma),suggesting enrichment in finer fraction of morerecently grown authigenic illites.The timing of the fault movement are the lower intercept ages at 0%detrital illite(19.2 ± 0.92 Ma and 19.4 ± 0.49 Ma).In combination with previous geochronological data,this result indicates that the metamorphism of the Day Nui Con Voi(DNCV) metamorphic complex took place before ca.26.8 Ma.At about 26.8 Ma-25 Ma,the fault strongly acted to cause the rapid exhumation of the rocks along the Red River-Ailoa Shan Fault Zone(RR-ASFZ).During brittle deformation,the DNCV slowly uplifted,implying weak movement of the fault.This brittle deformation might have lasted for ca.5 Ma. 相似文献