Integration system research and development for three-dimensional laser scanning information visualization in goaf

An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, cloud data de-noising optimization, construction, display and operation of three-dimensional model, model editing, profile generation, calculation of goaf volume and roof area, Boolean calculation among models and interaction with the third party soft ware. Concerning this system with a concise interface, plentiful data input/output interfaces, it is featured with high integration, simple and convenient operations of applications. According to practice, in addition to being well-adapted, this system is favorably reliable and stable.

Reduction of signal reflection along through silicon via channel in high-speed three-dimensional integration circuit

The through silicon via （TSV） technology has proven to be the critical enabler to realize a three-dimensional （3D） gigscale system with higher performance but shorter interconnect length. However, the received digital signal after trans- mission through a TSV channel, composed of redistribution layers （RDLs）, TSVs, and bumps, is degraded at a high data-rate due to the non-idealities of the channel. We propose the Chebyshev multisection transformers to reduce the signal reflec- tion of TSV channel when operating frequency goes up to 20 GHz, by which signal reflection coefficient （$11） and signal transmission coefficient （$21） are improved remarkably by 150% and 73.3%, respectively. Both the time delay and power dissipation are also reduced by 4% and 13.3%, respectively. The resistance-inductance-conductance-capacitance （RLGC） elements of the TSV channel are iterated from scattering （S）-parameters, and the proposed method of weakening the signal reflection is verified using high frequency simulator structure （HFSS） simulation software by Ansoft.

Spatial Governance of Multi-Plan Integration in the County Area:A Case Study of Sihui City

This study discussed the contradiction and reform experience of multi-plan integration in Sihui from the perspective of spatial governance.The research found:in terms of contradictions,the right and responsibility of management departments in the county area of Sihui were crosscutting,the township governance responsibilities needed urgent improvement,the urban-rural governance problems were different,the spatial governance elements were not unified,and the contradiction in the implementation mechanism was the implementation of projects.Through the multi-plan integration reform,Sihui reconstructed the right and responsibility relationship of the spatial governance departments,unified the elements of spatial governance,and refactored the implementation mechanism by reconstructing the transmission mechanism of the spatial planning system and the project approval mechanism and establishing the dynamic evaluation and adjustment mechanism.

Study on Si-SiGe Three-Dimensional CMOS Integrated Circuits

Based on the physical characteristics of SiGe material,a new three-dimensional （3D） CMOS IC structure is proposed,in which the first device layer is made of Si material for nMOS devices and the second device layer is made of Six Ge1- x material for pMOS. The intrinsic performance of ICs with the new structure is then limited by Si nMOS.The electrical characteristics of a Si-SiGe 3D CMOS device and inverter are all simulated and analyzed by MEDICI. The simulation results indicate that the Si-SiGe 3D CMOS ICs are faster than the Si-Si 3D CMOS ICs. The delay time of the 3D Si-SiGe CMOS inverter is 2-3ps,which is shorter than that of the 3D Si-Si CMOS inverter.

Real-time in situ three-dimensional integral videography and surgical navigation using augmented reality: a pilot study

To evaluate the feasibility and accuracy of a three-dimensional augmented reality system incorporating integral videography for imaging oral and maxillofacial regions, based on preoperative computed tomography data. Three-dimensional surface models of the jawbones, based on the computed tomography data, were used to create the integral videography images of a subject＇s maxillofacial area. The three-dimensional augmented reality system （integral videography display, computed tomography, a position tracker and a computer） was used to generate a three-dimensional overlay that was projected on the surgical site via a half-silvered mirror. Thereafter, a feasibility study was performed on a volunteer. The accuracy of this system was verified on a solid model while simulating bone resection. Positional registration was attained by identifying and tracking the patient/surgical instrument＇s position. Thus, integral videography images of jawbones, teeth and the surgical tool were superimposed in the correct position. Stereoscopic images viewed from various angles were accurately displayed. Change in the viewing angle did not negatively affect the surgeon＇s ability to simultaneously observe the three-dimensional images and the patient, without special glasses. The difference in three-dimensional position of each measuring point on the solid model and augmented reality navigation was almost negligible （〈1 mm）; this indicates that the system was highly accurate. This augmented reality system was highly accurate and effective for surgical navigation and for overlaying a three-dimensional computed tomography image on a patient＇s surgical area, enabling the surgeon to understand the positional relationship between the preoperative image and the actual surgical site, with the naked eye.

Through-silicon-via crosstalk model and optimization design for three-dimensional integrated circuits

Through-silicon-via （TSV） to TSV crosstalk noise is one of the key factors affecting the signal integrity of three- dimensional integrated circuits （3D ICs）. Based on the frequency dependent equivalent electrical parameters for the TSV channel, an analytical crosstalk noise model is established to capture the TSV induced crosstalk noise. The impact of various design parameters including insulation dielectric, via pitch, via height, silicon conductivity, and terminal impedance on the crosstalk noise is analyzed with the proposed model. Two approaches are proposed to alleviate the TSV noise, namely, driver sizing and via shielding, and the SPICE results show 241 rnV and 379 mV reductions in the peak noise voltage, respectively.

Three-Dimensional Cooperative Localization via Space-Air-Ground Integrated Networks

The space-air-ground integrated network(SAGIN)combines the superiority of the satellite,aerial,and ground communications,which is envisioned to provide high-precision positioning ability as well as seamless connectivity in the 5G and Beyond 5G(B5G)systems.In this paper,we propose a three-dimensional SAGIN localization scheme for ground agents utilizing multi-source information from satellites,base stations and unmanned aerial vehicles(UAVs).Based on the designed scheme,we derive the positioning performance bound and establish a distributed maximum likelihood algorithm to jointly estimate the positions and clock offsets of ground agents.Simulation results demonstrate the validity of the SAGIN localization scheme and reveal the effects of the number of satellites,the number of base stations,the number of UAVs and clock noise on positioning performance.

Continuous imaging space in three-dimensional integral imaging

We report an integral imaging method with continuous imaging space. This method simultaneously reconstructs real and virtual images in the virtual mode, with a minimum gap that separates the entire imaging space into real and virtual space. Experimental results show that the gap is reduced to 45% of that in a conventional integral imaging system with the same parameters.

Integrated Climate Change Risk Governance in China under the Background of Global Climate Governance

Climate change in the past one hundred years has brought important influence to the natural ecosystem and social-economic system of the world and China.The impact of future climate change is also long-term and huge,and many effects are negative or adverse.Therefore,from now on we must take measures adapting to climate change to overcome the adverse effects of climate change on social-economic-ecological system.In this paper,starting from the urgency of integrated climate change risk governance,the risk of natural disasters intensifying caused by climate change is briefly described,and engineering and non engineering measures of the integrated climate change risk governance in China's high risk region are proposed,as well as recommendations on integrated risk governance in the eastern,middle and western China.

Forming mechanism of three-dimensional integral fin based on flat surface

To improve heat-transfer performance, a novel integral three-dimensional fin-structure on the plat surface was presented to increase the evaporation efficiency. The three-dimensional fin-structure is composed of a spiral micro-groove and multi radial micro-grooves. Both ploughing-extrusion(P-E) and stamping were used to form the integral-fins with a connection between radial and circumferential directions. Based on the SEM results, the relationships among P-E speed v P-E, rotational speed np and feed fp, and among interference length Li, stamping feed angle θc and stamping depth ac were analyzed. The effects of processing parameters on the groove morphology and the matching relationship between parameters were also discussed. The integral finned surface with micro-grooves and cracks can be obtained under such processing conditions: P-E depth ap=0.3 mm, ac=0.3 mm, the interval of helical groove dp=1.24 mm, θc=2° and np=50 r/min.

Validating Governance Performance Indicators for Integrated Coastal and Ocean Management in the Southeast Region of Cuba

The importance of evaluating the success of policies developed to effectively manage coastal and marine resource use is well documented. However, few frameworks exist that allow for a comparative examination of existing policy instruments, as opposed to specific initiatives, which assess governance performance aimed at addressing issues arising in the coastal zone. This paper describes the process and findings for evaluating the feasibility of a modified Coastal Sustainability Standard (CoSS) framework that seeks to measure the effectiveness of individual planning instruments within overlapping spatial boundaries in the landward and marine areas in the southeast region of Cuba. Through workshops conducted in Santiago de Cuba and Guamá municipalities with key representatives involved in coastal management and planning, the utility of the framework was assessed using the main instruments of territorial planning in Cuba, namely integrated river basin management, territorial planning in coastal municipalities and marine and coastal management. While, the findings suggest that the modified CoSS framework can be used to assess the effectiveness of these planning instruments in the region, and workshop participants also suggested improvements to better match its use to the characteristics of the study region.

The Local Process of Governance in Integrated Water Resource Management： An Example of the Wadi El K^bir Watershed （Northeast of Algeria）

Alternatives to the sectoral and public policies and regulations of environmental and water resources＇ protection, and the experiments of integrated management have been rapidly multiplied since the year 1990. Water constitutes a principal stake of these environmental policies in the majority of the countries and especially in the countries of North Africa as Algeria, where this resource is threatened by repeated dryness and by the impact of the climate change. The integrated water resource management reflects today the world tendency of the governments to exploit and preserve this resource by a way based on a process of governance, which passes by the dialog of diversified actors （various sectors）. According to this policy and to the promulgation of the Algerian National Report on State effective implementation and coordination mechanisms are required. How this principle of integrated water management will be executed with various scenarios in Algeria and what are the main difficulties that can be met？ Or, more exactly, what are the variables that can influence the operation of the local water process governorship？ This analysis will be carried out through the example of the Wadi El K6bir watershed located in the northeast of Algeria, which is real natural area of water supply that feeds the communities, the natural and artificial basins, and preserves the perenniality of the existing natural ecosystems especially the one of the natural park classified by the United Nations Educational Scientific and Cultural Organization （U.N.E.S.C.O） in 1989 as the inheritance of humanity and six other sites classified according to the Ramsar convention as wetlands of international importance to be preserved.

High Optical Magnification Three-Dimensional Integral Imaging of Biological Micro-organism

A high optical magnification three-dimensional imaging system is proposed using an optic microscope whose ocular （eyepiece） is retained and the structure of the transmission mode is not destroyed. The elemental image array is captured through the micro lens array. Due to the front diffuse transmission element, each micro lens sees a slightly different spatial perspective of the scene, and a different independent image is formed in each micro lens channel. Each micro lens channel is imaged by a Fourier lens and captured by a CCD. The design translating the stage in x or y provides no parallax. Compared with the conventional integral imaging of micro-objects, the optical magnification of micro-objects in the proposed system can enhanced remarkably. The principle of the enhancement of the image depth is explained in detail and the experimental results are presented.

破与立:协同治理机制的整合与重构——评Collaborative Governance Regimes

协同治理日益成为激变时代解决公共问题的治道选择,并引起学术界的强烈关注。然而,已有研究却呈现碎片化、拼凑化的特点,如何进行理论整合并重构分析框架成为当前的理论诉求。柯克·爱默生和蒂娜·娜芭齐基于文献分析与经验研究,从治理环境和棘手问题两个方面讨论协同治理的生成机理,重新定义协同治理的内涵,整合协同治理的知识谱系,并构建了协同治理机制的综合性分析框架。她们的研究无疑成为相关领域的重要参考。当然,该项研究仍然具有值得拓展的空间,本文最后一部分对此进行探讨。

Three-dimensional numerical manifold method for heat conduction problems with a simplex integral on the boundary

The three-dimensional numerical manifold method(3D-NMM),which is based on the derivation of Galerkin's variation,is a powerful calculation tool that uses two cover systems.The 3D-NMM can be used to handle continue-discontinue problems and extend to THM coupling.In this study,we extended the 3D-NMM to simulate both steady-state and transient heat conduction problems.The modelling was carried out using the raster methods(RSM).For the system equation,a variational method was employed to drive the discrete equations,and the crucial boundary conditions were solved using the penalty method.To solve the boundary integral problem,the face integral of scalar fields and two-dimensional simplex integration were used to accurately describe the integral on polygonal boundaries.Several numerical examples were used to verify the results of 3D steady-state and transient heat-conduction problems.The numerical results indicated that the 3D-NMM is effective for handling 3D both steadystate and transient heat conduction problems with high solution accuracy.

Interaction of two three-dimensional explosion bubbles

The interaction of two underwater explosion bubbles was mathematically analyzed in this paper. Based on the assumption of potential flow, high-order curved elements were used to discretize the boundary integral equation and solve it. Assuming that gas inside the bubble follows the isentropic rule, the Euler-Lagrange method was used to trace the evolution of the bubble, and when calculating the singular integral, the singularity of the double-layer singular integral was eliminated by reconstructing a principal-value integral of double-layer potential so that a more precise result could be obtained. Elastic mesh technique (EMT) was also used when tracing the evolution of the bubble interface, and numerical smoothing wasn't needed. A comparison of calculations using this three-dimensional model with results of the Reyleigh-Plesset bubble model shows that the three-dimensional model and calculation method in this paper is practical. This three-dimensional model was applied to simulate the interaction of two bubbles under the action of gravity, and the dynamic characteristics of two bubbles near the surface was also analyzed. Bubbles influenced by surface effects and gravity present severe non-linearity. This paper provides a reference for research into the dynamics of multi-bubbles.

Three-Dimensional Analysis of Rolling by Twin Shear Stress Yield Criterion

Using the twin shear stress yield criterion, the surface integral of the co-line vectors, and the integration depending on upper limit, Kobayashi＇s three-dimensional velocity field of rolling was analyzed and an analytical expression of rolling torque and single force was obtained. Through redoing the same experiment of rolling pure lead as Sims, the calculated results by the above expression were compared with those of Kobayashi and Sims formulae. The results show that the twin shear stress yield criterion is available for rolling analysis and the calculated results by the new formula are a little higher than those by Kobayashi and Sims ones if the reduction ratio is less than 30%.

Microstructure-based three-dimensional characterization of chip formation and surface generation in the machining of particulate-reinforced metal matrix composites

Particulate-reinforced metal matrix composites(PRMMCs)are difficult to machine due to the inclusion of hard,brittle reinforcing particles.Existing experimental investigations rarely reveal the complex material removal mechanisms(MRMs)involved in the machining of PRMMCs.This paper develops a three-dimensional(3D)microstructure-based model for investigating the MRM and surface integrity of machined PRMMCs.To accurately mimic the actual microstructure of a PRMMC,polyhedrons were randomly distributed inside the matrix to represent irregular SiC particles.Particle fracture and matrix deformation and failure were taken into account.For the model’s capability comparison,a two-dimensional(2D)analysis was also conducted.Relevant cutting experiments showed that the established 3D model accurately predicted the material removal,chip morphology,machined surface finish,and cutting forces.It was found that the matrix-particle-tool interactions led to particle fractures,mainly in the primary shear and secondary deformation zones along the cutting path and beneath the machined surface.Particle fracture and dilodegment greatly influences the quality of a machined surface.It was also found that although a 2D model can reflect certain material removal features,its ability to predict microstructural variation is limited.

Three-dimensional global interconnect based on a design window

Based on a stochastic wire length distributed model, the interconnect distribution of a three-dimensional integrated circuit （3D IC） is predicted exactly. Using the results of this model, a global interconnect design window for a giga-scale system-on-chip （SOC） is established by evaluating the constraints of 1） wiring resource, 2） wiring bandwidth, and 3） wiring noise. In comparison to a two-dimensional integrated circuit （2D IC） in a 130-nm and 45-nm technology node, the design window expands for a 3D IC to improve the design reliability and system performance, further supporting 3D IC application in future integrated circuit design.

Research on Urban Community Facilities Safety Governance—Based on the Overall Perspective

Community facilities accidents happen every year in many cities of China, which has been an important issue in academic circles. The purpose of this study is to suggest the direction of universal design for the prevention of community facilities accidents. In this paper, from the overall angle, the impact factors of the urban community service facilities safety were analyzed. Then, based on the integrated governance theory, from such aspects as engineering and non-engineering disaster reduction, the governance measures were explored.