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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

Gene therapy for Parkinson's disease: a decade of progress supported by posthumous contributions from volunteer subjects

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Neural Regeneration Research 2015年第10期10卷 1586-1588页

作者： Raymond T.Bartus RTBioconsultants Inc. formerly EVP and CSO Ceregene Inc.

Over the past decade,nine separate gene therapy clinical trials for advanced Parkinson’s disease（PD）have been launched and completed,involving the dosing of nearly 12-dozen PD volunteers who inc.rred significant ri... 详细信息

关键词： Gene therapy for Parkinson’s disease a decade of progress supported by posthumous contributions from volunteer subjects

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

Engineering models for catastrophe risk and their application to insurance

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Earthquake Engineering and Engineering Vibration 2002年第1期1卷 145-151页

作者： Weimin Dong Risk Management Solutions,inc.USA Ph.D and Visiting Professor of Institute of Engineering Mechanics RMS Inc. Newark USA

Internationally earthquake insurance,like all other insurance (fire,auto),adopted actuarial approach in the past, which is,based on historical loss experience to determine insurance *** to the fact that earthquake is a rare event with severe consequence,irrational determination of premium rate and lack of understanding scale of potential loss led to many insurance companies insolvent after Northridge earthquake in 1994. Along with recent advances in earth science,computer science and engineering,computerized loss estimation methodologies based on first princ.ples have been developed to the point that losses from destructive earthquakes can be quantified with reasonable accuracy using scientific modeling techniques. This paper intends to introduce how engineering models can assist to quantify earthquake risk and how insurance industry can use this information to manage their risk in the United States and abroad.

关键词： risk insurance earthquake engineering model