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On the radiative and thermodynamic properties of the cosmic radiations using COBE FIRAS instrument data: Ⅲ. Galactic far-infrared radiation

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Research in Astronomy and Astrophysics 2015年第7期15卷 939-952页

作者： Anatoliy I Fisenko Vladimir Lemberg ONCFEC inc.

Using the three-component spectral model describing the FIRAS average continuum spectra, the exact analytical expressions for thermodynamic and radiative functions of Galactic far-infrared radiation are obtained. The COBE FIRAS instrument data in the 0.15-2.88 THz frequency interval at the mean temperatures of T1= 17.72 K, T2= 14 K and T3= 6.73 K are used for calculating the radiative and thermodynamic functions, such as the total radiation power per unit area, total energy density, total emissivity, number density of photons, Helmholtz free energy density, entropy density, heat capacity at constant volume and pressure for the warm,intermediate-temperature and very cold components of the Galactic continuum spectra. The generalized Stefan-Boltzmann law for warm, intermediate-temperature and very cold components is constructed. The temperature dependence of each component is determined by the formula IS-B（T） = σ′ T6. This result is important when we construct the cosmological models of radiative transfer that can be applied inside the Galaxy. Within the framework of the three-component spectral model, the total number of photons in our Galaxy and the total radiation power（total luminosity） emitted from a surface of the Galaxy are calculated. Their values are N6Gtotal= 1.3780 × 108 and I3Gtotal（T） = 1.0482 × 106 W. Other radiative and thermodynamic properties of the Galactic far-infrared radiation（photon gas） of the Galaxy are calculated. The expressions for astrophysical parameters, such as the entropy density/Boltzmann constant and number density of the Galactic far-infrared photons are obtained. We assume that the obtained analytical expressions for thermodynamic and radiative functions may be useful for describing the continuum spectra of the far-infrared radiation for other galaxies.

关键词： Galaxy: general -- galaxies: general

Challenges of mining the first right-handed longwall panel in a new reserve block in Pittsburgh Seam

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International Journal of Mining Science and Technology 2019年第1期29卷 145-149页

作者： Jun Lu Greg Hasenfus CONSOL Energy inc.

In this paper, the mining experience and challenges for the first right-handed longwall panel in the Pittsburgh Seam are introduced. The longwall headgate T-junction experienced very high face convergence(up to 61 cm), accompanied by roof sag, floor heave, and rib loading. The headgate convergence was so large that, in a few places, it threatened longwall retreat and ultimately required the bottom to be re-graded. Different underground instruments, such as a roof scope, de-gas drill, tell-tale, laser meter,and borehole pressure Cell(BPC), were employed to explore the roof geology and to monitor the entry convergence and the stress changes in the pillar. In addition, the impact of other geologic factors, such as large overburden depth, laminated sandstone roof geology, soft floor, and large headgate equipment,were also analyzed. Subsequently, geotechnical solutions were provided to avoid or mitigate the impact of these challenging geologic factors.

关键词： Coal mining Horizontal stress Ground control Roof convergence

Fatman： Building Reliable Archival Storage Based on Low-Cost Volunteer Resources

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Journal of Computer Science & Technology 2015年第2期30卷 273-282页

作者：覃安胡殿明刘俊杨文君谭待 Baidu inc. Beijing 100193 China

We present Fatman, an enterprise-scale archival storage based on volunteer contribution resources from underutilized web servers, usually deployed on thousands of nodes with spare storage capacity. Fatman is specifically designed for enhancing the utilization of existing storage resources and cutting down the hardware purchase cost. Two major concerned issues of the system design are maximizing the resource utilization of volunteer nodes without violating service level objectives （SLOs） and minimizing the cost without reducing the availability of archival system. Fatman has been widely deployed on tens of thousands of server nodes across several datacenters, providing more than 100 PB storage capacity and serving dozens of internal mass-data applications. The system realizes an efficient storage quota consolidation by strong isolation and budget limitation, to maximally support resource contribution without any degradation on host-level SLOs. It novelly improves data reliability by applying disk failure prediction to minish failure recovery cost, named fault-aware data management, dramatically reduces the mean time to repair （MTTR） by 76.3% and decreases file crash ratio by 35% on real-life product workload.

关键词： volunteer storage failure prediction, failure recovery, reliability, archival storage

EXPERIMENTAL AND NUMERICAL INVESTIGATION OF BUBBLE AUGMENTED WATERJET PROPULSION

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Journal of Hydrodynamics 2012年第5期24卷 635-647页

作者： CHOI Jin-Keun SINGH Sowmitra HSIAO Chao-Tsung CHAHINE Georges L DYNAFLOW inc. JessupMarylandUSA

This contribution presents experimental and numerical investigations of the concept jet propulsion augmentation using bubble injection. A half-3D （D-shaped cylindrical configuration to enable optimal visualizations） divergent-convergent nozzle was designed, built, and used for extensive experiments under different air injection conditions and thrust measurement schemes. The design, optimization, and analysis were conducted using numerical simulations. The more advanced model was based on a two-way coupling between an Eulerian description of the flow field and a Lagrangian tracking of the injected bubbles using our Surface Averaged Pressure （SAP） model. The numerical results compare very favorably with nozzle experiments and both experiments and simulations validation the thrust augmentation concept. For a properly designed nozzle and air injection system, air injection produces net thrust augmentation, which inc.eases with the rate of bubble injection. Doubling of thrust was measured for a 50% air injection rate. This beneficial effect remains at 50% after account for liquid pump additional work to overcome inc.eased pressure by air injection.

关键词： waterjet propulsion bubble dynamics multi-phase flow

Neurodegenerative diseases are a function of matrix breakdown:how to rebuild extracellular matrix and intracellular matrix

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Neural Regeneration Research 2018年第7期13卷 1185-1186页

作者： Greg Maguire Bio Regenerative Sciences Inc.Neo GenesisInc.

Matrix within cells,the cytoskeleton,and that which surrounds cells,the extracellular matrix（ECM）,are connected to one another through a number of receptors inc.uding those in primary cilia,serving as an important chemical and physical signaling system：Mechanical forces generated through the matrix play a critical role in determining the form and function of tissues（Hughes et al.,2018）.

关键词： ECM Neurodegenerative diseases are a function of matrix breakdown:how to rebuild extracellular matrix and intracellular matrix

Development of a multiple level underground limestone mine from geology through mine planning

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International Journal of Mining Science and Technology 2020年第1期30卷 63-67页

作者： Christopher Newman David Newman Robert Dupuy Appalachian Mining&Engineering Inc.LexingtonKYUSA Rogers Group Inc.NashvilleTNUSA

The development of a multiple level underground mine is a complex task in which geology,engineering,ground control,and unit operations are integrated into a single mine *** components are interdependent and must function cohesively to ensure a profitable underground mining *** optimize reserve recovery,mine planning should begin from the lowest level and progress *** limits any misjudgments or oversights of a given level affecting the underlying levels and ensures the ability to maximize recovery from each *** planning should start with the exploration and characterization of the geologic *** the reserve geology and quality is well understood,then mine planning can begin with respect to the following:(1)orientation of mine works with respect to horizontal stress;(2)access to the reserve;(3)determination of opening widths;(4)selection of back,floor horizons and pillar centers;(5)selection of development and secondary mining heights;(6)appropriate inter-burden thicknesses;and(7)examining the stability of the multiple level mine through numerical *** multiple level mine design process and decisions are presented through a case history *** theme is that there is one opportunity to"get it right"and many chances to overlook a small aspect within the design that will plague the mine throughout all levels and through the entirety of its operating life.

关键词： Limestone Mine planning Geology Multiple level Rock mechanics

SDN Orchestration for Dynamic End-to-End Control of Data Center Multi-Domain Optical Networking

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China Communications 2015年第8期12卷 10-21页

作者： LIU Lei Fujitsu Laboratories of America inc.

New and emerging use cases, such as the interconnection of geographically distributed data centers(DCs), are drawing attention to the requirement for dynamic end-to-end service provisioning, spanning multiple and heterogeneous optical network domains. This heterogeneity is, not only due to the diverse data transmission and switching technologies, but also due to the different options of control plane techniques. In light of this, the problem of heterogeneous control plane interworking needs to be solved, and in particular, the solution must address the specific issues of multi-domain networks, such as limited domain topology visibility, given the scalability and confidentiality constraints. In this article, some of the recent activities regarding the Software-Defined Networking(SDN) orchestration are reviewed to address such a multi-domain control plane interworking problem. Specifically, three different models, inc.uding the single SDN controller model, multiple SDN controllers in mesh, and multiple SDN controllers in a hierarchical setting, are presented for the DC interconnection network with multiple SDN/Open Flow domains or multiple Open Flow/Generalized Multi-Protocol Label Switching( GMPLS) heterogeneous domains. I n addition, two concrete implementations of the orchestration architectures are detailed, showing the overall feasibility and procedures of SDN orchestration for the end-to-endservice provisioning in multi-domain data center optical networks.

关键词： software-defined networking(SDN) generalized multi-protocol labelswitching (GMPLS) path computationelement (PCE) data center orchestration multi-domain optical network

Consistent constitutive modeling of metallic target penetration using empirical, analytical, and numerical penetration models

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Defence Technology（防务技术） 2016年第2期12卷 201-213页

作者： John(Jack) P.RIEGEL III David DAVISON R3 Technology Inc. 7324 Fountain Spring Ct. Shock Transients Inc.

Historically, there has been little correlation between the material properties used in(1) empirical formulae,(2) analytical formulations, and(3) numerical models. The various regressions and models may each provide excellent agreement for the depth of penetration into semi-infinite targets. But the input parameters for the empirically based procedures may have little in common with either the analytical model or the numerical model. This paper builds on previous work by Riegel and Anderson(2014) to show how the Effective Flow Stress(EFS) strength model, based on empirical data, can be used as the average flow stress in the analytical Walker–Anderson Penetration model(WAPEN)(Anderson and Walker,1991) and how the same value may be utilized as an effective von Mises yield strength in numerical hydrocode simulations to predict the depth of penetration for eroding projectiles at impact velocities in the mechanical response regime of the materials. The method has the benefit of allowing the three techniques(empirical, analytical, and numerical) to work in tandem. The empirical method can be used for many shot line calculations, but more advanced analytical or numerical models can be employed when necessary to address specific geometries such as edge effects or layering that are not treated by the simpler methods. Developing complete constitutive relationships for a material can be costly. If the only concern is depth of penetration, such a level of detail may not be required. The effective flow stress can be determined from a small set of depth of penetration experiments in many cases, especially for long penetrators such as the L/D = 10 ones considered here, making it a very practical approach. In the process of performing this effort, the authors considered numerical simulations by other researchers based on the same set of experimental data that the authors used for their empirical and analytical assessment. The goals were to establish a baseline with a full constitut

关键词：本构模型渗透模型数值模型金属靶材料性质流动应力程序模拟数值计算

MODELING MICROBUBBLE DYNAMICS IN BIOMEDICAL APPLICATIONS

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Journal of Hydrodynamics 2012年第2期24卷 169-183页

作者： CHAHINE Georges L. HSIAO Chao-Tsung Dynaflow Inc.JessupMaryland 20794USA

Controlling microbubble dynamics to produce desirable biomedical outcomes when and where necessary and avoid deleterious effects requires advanced knowledge, which can be achieved only through a combination of experimental and numerical/ analytical techniques. The present communication presents a multi-physics approach to study the dynamics combining viscous- inviscid effects, liquid and structure dynamics, and multi bubble interaction. While complex numerical tools are developed and used, the study aims at identifying the key parameters influencing the dynamics, which need to be inc.uded in simpler models.

关键词： microbubble biological contrast agents thick shell ultrasound