在“做好科学教育加法”背景下挖掘“三深”课堂内涵

针对我校学生思维水平低、协作能力低和科学研究欲望低的现状,笔者欲构建“三深”科学课堂。“三深”,即深度思维、深度协作和深度研究。本文在“做好科学教育加法”背景下,挖掘“三深”科学课堂内涵。

“三深”金属矿产资源开采利用的绿色化思考

“三深”(深空、深海、深地)矿产资源储量丰富,是未来资源开发的重要新领地。介绍了“三深”矿产资源的组成、分布等概况,叙述了国内外对“三深”矿产资源开发的需求、战略及规划,揭示了“三深”环境特点及其矿物富集提取的挑战,综述了“三深”金属矿产资源开采利用技术研究现状。基于前人提出的“三深”金属矿产资源开采、选矿、冶金等相关技术原型,指出未来“三深”金属矿产资源的开发应把保护环境放在突出位置,防止太空污染、海洋污染、深地污染,使环境扰动控制在较低水平,实现绿色化开采、洁净化选冶及低碳清洁生产,并提出“三深”金属矿产资源开采利用的绿色化技术路径,进而引出了未来“三深”绿色矿山建设的设想。

伊犁矿区浅埋深“三软”厚煤层首采工作面矿压规律研究

为了掌握新疆伊犁矿区浅埋深厚煤层开采矿压特点,利用支架压力监测、地表岩移观测和煤体超前应力监测等实测手段,对新疆伊犁四矿首采21103工作面在浅埋深薄基岩"三软"厚煤层条件下的矿压规律进行分析。结果表明:工作面基本顶初次来压步距约21m,周期来压步距平均11m,动载系数平均1.22~1.25,工作面矿压显现整体不强烈,现有ZFY13000/24/42型放顶煤支架适应性良好;工作面超前支承压力分布具有应力集中系数低、超前影响范围小等特征,对回采巷道影响不显著;研究结论为类似条件工作面安全高效回采提供有益借鉴。

“三纵三深”工程模板实践教学体系的构建与实践

分析了现代焊接技术与工程、材料成型及控制工程的人才需求,指出了现代工程问题的复杂性、综合性特点,剖析了现代工程应用型人才的工程应用能力结构和工程素质。在遵循高等工程教育规律的前提下,构建了具有"三纵三深"特征的实践教学体系,创立了工程模板教学模式,制定了一整套完善的、与工程应用能力结构和工程素质相配套的教学训练方案和考核纲要,阐述了重要工程训练环节的内涵。经多轮实践证明:新体系可显著增强学生的工程应用能力,有效提高学生的工程素质。

实践“三个代表”的创新性探索

长治市委提出的“深入基层、深入群众、深入人心” ,是实践“三个代表”要求的创新性探索 ,对提高干部素质和改进党的作风都会起重要的促进作用。

Using 3D TCAD Simulation to Study Charge Collection of a p-n Junction in a 0.18μm Bulk Process

Single event transient of a real p-n junction in a 0.18μm bulk process is studied by 3D TCAD simulation. The impact of voltage, temperature, substrate concentration, and LET on SET is studied. Our simulation results demonstrate that biases in the range 1.62 to 1.98V influence DSET current shape greatly and total collected charge weakly. Peak current and charge collection within 2ns decreases as temperature increases,and temperature has a stronger influence on SET currents than on total charge. Typical variation of substrate concentration in modern VDSM processes has a negligible effect on SEEs. Both peak current and total collection charge increases as LET increases.

“三讲”重在“三深一建”

江泽民同志早于1995年在北京考察工作时,即以敏锐的政治洞察力,高瞻远瞩,作出了领导干部要讲学习、讲政治、讲正气的重大部署。此后的多次讲话中又作出了深刻阐述和强调。在党的十五大报告中进一步指出:要“继续在县级以上领导干部中深入进行以讲学习、讲政治、讲正气为主要内容的党性党风教育。”如何实现以江泽民同志为核心的党中央的部署和决心,深入搞好“三讲”教育呢?依笔者之见,要在“三深一建”上下功夫。

Model and optimization of ultrasonic phased array parameters

Beam focusing is one of the unique characteristics of ultrasonic phased array compared with conventional ultrasound.On the basis of two-dimensional radiated sound field of phased array,the three-dimensional radiated sound field was simulated in the paper,and then the effect of different frequencies,different number of array elements and different element spacings on focal spot,the depth of focus and the effect on horizontal and vertical resolution were analyzed.The optimal results of transducer parameters have certain reference value for the design of phased array probe.

Implication of Geochemical Simulation for CO2 Storage Using Data of York Reservoir

In this paper, we build up a three-dimensional model for CO2 storage in the deep reservoir. And this paper gives the mathematical formalism of combined geochemical and multi-phase flow. The results give us the information about geochemical changing caused by CO2 injection into aqueous, the dissolution or precipitation of reservoir minerals caused by aqueous components change, the change of water density, also the differences between this model and the simulation model without considering geochemical. The basic data for simulation is from York Reservoir.

Three-dimensional gravity inversion based on 3D U-Net++

The gravity inversion is to restore genetic density distribution of the underground target to be explored for explaining the internal structure and distribution of the Earth.In this paper,we propose a new 3D gravity inversion method based on 3D U-Net++.Compared with two-dimensional gravity inversion,three-dimensional(3D)gravity inversion can more precisely describe the density distribution of underground space.However,conventional 3D gravity inversion method input is two-dimensional,the input and output of the network proposed in our method are three-dimensional.In the training stage,we design a large number of diversifi ed simulation model-data pairs by using the random walk method to improve the generalization ability of the network.In the test phase,we verify the network performance by using the model-data pairs generated by the simulation.To further illustrate the eff ectiveness of the algorithm,we apply the method to the inversion of the San Nicolas mining area,and the inversion results are basically consistent with the borehole measurement results.Moreover,the results of the 3D U-Net++inversion and the 3D U-Net inversion are compared.The density models of the 3D U-Net++inversion have higher resolution,more concentrated inversion results,and a clearer boundary of the density model.

对地观测技术在土地管理中的应用及展望

随着"三深一土"国土资源科技创新战略的全面实施,将更高精度、更高时效的对地观测技术应用于我国土地数量、质量、生态"三位一体"监管体系的建设中,能够实时、精准、连续地为土地调查评价、耕地保护、土地综合整治、资源节约集约利用提供技术支撑,提升监管效能和水平。文中详细论述了遥感对地观测技术在土地管理中的应用现状,并结合深空对地观测技术的发展前景,进一步阐述了遥感对地观测技术在土地管理综合监测体系中的应用方向,为深空技术更好地服务于土地管理工作提供前瞻性分析。

Collapse mechanism of deep tunnels with three-centered arch cross section

The possible collapse of different circumstances is derived with the help of the limit analysis theory.Analytical equations related to collapsing mechanisms in deep tunnel with smooth three-centered arc cross sections are derived on the basis of Hoek-Brown failure criterion and upper bound limit analysis.The pore water pressure is considered in the analysis,as a work rate of external force.Numerical results about the shape of detaching curve and the weight of collapsing block per unit length corresponding to different parameters are obtained with the help of mathematical software.The shapes of collapsing block are drawn with respected to different parameters.Furthermore,the effects of different parameters on the shape of detaching curve and the weight of the collapsing block are discussed.

Experimental evaluation and modeling of liquid jet penetration to estimate droplet size in a three-phase riser reactor

In this work, the effects of injecting an evaporating liquid jet into solid-gas flow are experimentally investigated. A new model （SHED model） and a supplementary model （spray model） have also been proposed to investigate some flow-field characteristics in three-phase fluidized bed with the mean relative error 4.3% between model and measured results. Some experiments were conducted to study the influences of flow-field parameters such as liquid volumetric flow rate, injection velocity, jet angle and gas superficial velocity as well as solid mass flux on the jet penetration depth （JPD）. In addition, independent variables were experimentally employed to propose two empirical correlations for JPD by using multiple regression method and spray cone angle （SCA） by using dimensional analysis technique. The mean relative errors between the JPD and SCA correlations versus ex- perimental data were 7.5% and 3.9%, respectively. In addition, in order to identify the variable effect, a parametric study was carried out. Applying the proposed model can avoid direct use of expensive devices to measureJPD and to nredict dronlet size.

Experimental investigation on influence of loading rate on rockburst in deep circular tunnel under true-triaxial stress condition

To investigate the influence of loading rate on rockburst in a circular tunnel under three-dimensional stress conditions,the true-triaxial tests were conducted on 100 mm×100 mm×100 mm cubic sandstone specimens with d50 mm circular perforated holes,and the failure process of hole sidewall was monitored and recorded in real-time by the microcamera.The loading rates were 0.02,0.10,and 0.50 MPa/s.The test results show that the rockburst process of hole sidewall experienced calm period,pellet ejection period,rock fragment exfoliation period and finally formed the V-shaped notch.The rockburst has a time lag and vertical stress is high when the rockburst occurs.The vertical stress at the initial failure of the hole sidewall increases with loading rate.During the same period after initial failure,the rockburst severity of hole sidewalls increased significantly with increasing loading rate.When the vertical stress is constant and maintains a high stress level,the rockburst of hole sidewall under low loading rate is more serious than that under high loading rate.With increasing loading rate,the quality of rock fragments produced by the rockburst decreases,and the fractal dimension of rock fragments increases.

3-D reconstruction of coastal bathymetry from AIRSAR/POLSAR data

This paper introduces a new method for reconstructing three-dimensional （3D） coastal bathymetry changes from Airborne AIRSAR/POLSAR synthetic aperture data. The new method is based on integration between fuzzy B-spline and Volterra algorithm. Volterra algorithm is used to simulate the ocean surface current from AIRSAR/POLSAR data. Then, the ocean surface current information used as input for continuity equation to estimate the water depths from AIRSAR/POLSAR data. This study shows that 3D ocean bathymetry can be reconstructed from AIRSAR/POLSAR data with root mean square error of ±0.03 m.

Numerical simulation of flocculation and settling behavior of whole-tailings particles in deep-cone thickener

Rapid dewatering and thickening of whole-tailings with ultrafine particles is one of the most important processes for the whole-tailings paste preparation. Deep-cone thickener, a kind of such process for the flocculation and settling of whole-tailings, is particularly necessary to study. However, there exist many problems in observing the flocculation and settling process of whole-tailings, as well as the particle size distribution(PSD) of whole-tailings floccules in deep-cone thickener. Population balance model(PBM) is applied to predict the PSD in deep-cone thickener, and LUO model and GHADIRI model are employed to study the aggregation and fragmentation mechanism of the whole-tailings particles, respectively. Through three-dimensional numerical simulation on the whole-tailings flocculation and settling in deep-cone thickener using computational fluid dynamics(CFD)-PBM, the distribution of density and turbulent kinetic energy in deep-cone thickener were obtained, at the same time the spatio-temporal changes of whole-tailings floccules particle size distribution are analyzed. Finally, the major flocculation position in deep-cone thickener is found and the flocculation settling rules of whole-tailings are achieved.

A Field Investigation on the Effects of Background Erosion on the Free Span Development of a Submarine Pipeline

The safety of submarine pipelines is largely influenced by free spans and corrosions. Previous studies on free spans caused by seabed scours are mainly based on the stable environment, where the background seabed scour is in equilibrium and the soil is homogeneous. To study the effects of background erosion on the free span development of subsea pipelines, a submarine pipe- line located at the abandoned Yellow River subaqueous delta lobe was investigated with an integrated surveying system which in- eluded a Multibeam bathymetric system, a dual-frequency side-scan sonar, a high resolution sub-bottom profiler, and a Magnetic Flux Leakage （MFL） sensor. We found that seabed homogeneity has a great influence on the free span development of the pipeline. More specifically, for homogeneous background scours, the morphology of scour hole below the pipeline is quite similar to that without the background scour, whereas for inhomogeneous background scour, the nature of spanning is mainly dependent on the evolution of seabed morphology near the pipeline. Magnetic Flux Leakage （MFL） detection results also reveal the possible connec- tion between long free spans and accelerated corrosion of the pipeline.

从南海10年展望深海科技前景

近10年来南海成为世界深海研究的热点。最为突出的是国家自然科学基金委员会支持的“南海深海过程演变(2011—2018年)”重大研究计划,我国科学家从中作出了突破性的贡献。这些科学成就的取得,很大程度是依靠引入“三深”技术探索深海,包括深潜、深钻和深网。迄今为止,我国深海探索的重心局限于南海北部,有待发起新的大型计划探索南部海盆,进而使南海成为全球海洋科学的天然实验室。

The Influences of American Deep Image on the Third-Generation Poets in China

The Third-Generation Poetry of China （namely Post-misty Poetry too） initiated with the introduction of Western modernist poetry, especially sorts of American Post-modernist poetry schools into China. ＂The relation between American poetry and Chinese poetry has a long history, which lies in the influences on the creation of the Third-Generation poets. This influence is probably unprecedented in its depth and breadth.＂ ＂Irrational association＂ and ＂leaping images＂ proposed by American Deep Image poets influenced by Freudian and Jungian unconscious perception gained an extraordinary appreciation among the Third-Generation poets who were in pursuit constantly of the experiments on poetic form and language. This paper mainly discusses the influences of American Deep Image on the Third-Generation poets of China through a case study of WANG Yin and CHEN Dongdong＇s poems.