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Xing, Y.

Publications and source records attributed to Xing, Y..

11 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

GPU-based optical simulation of the DARWIN detector

Abstract Understanding propagation of scintillation light is critical for maximizing the discovery potential of next-generation liquid xenon detectors that use dual-phase time projection chamber technology. This work describes a detailed optical simulation of the DARWIN detector implemented using Chroma, a GPU-based photon tracking framework. To evaluate the framework and to explore ways of maximizing efficiency and minimizing the time of light collection, we simulate several variations of the conventional detector design. Results of these selected studies are presented. More generally, we conclude that the approach used in this work allows one to investigate alternative designs faster and in more detail than using conventional Geant4 optical simulations, making it an attractive tool to guide the development of the ultimate liquid xenon observatory.

Instruments & Instrumentation↗
DOE OSTI2018

Semi‐dominant mutation in the cysteine‐rich receptor‐like kinase gene, ALS 1 , conducts constitutive defence response in rice

Abstract Plants have evolved a sophisticated two‐branch defence system to prevent the growth and spread of pathogen infection. The novel Cys‐rich repeat ( CRR ) containing receptor‐like kinases, known as CRK s, were reported to mediate defence resistance in plants. For rice, there are only two reports of CRK s. A semi‐dominant lesion mimic mutant als1 (apoptosis leaf and sheath 1) in rice was identified to demonstrate spontaneous lesions on the leaf blade and sheath. A map‐based cloning strategy was used for fine mapping and cloning of ALS 1 , which was confirmed to be a typical CRK in rice. Functional studies of ALS 1 were conducted, including phylogenetic analysis, expression analysis, subcellular location and blast resistance identification. Most pathogenesis‐related ( PR ) genes and other defence‐related genes were activated and up‐regulated to a high degree. ALS 1 was expressed mainly in the leaf blade and sheath, in which further study revealed that ALS 1 was present in the vascular bundles. ALS 1 was located in the cell membrane of rice protoplasts, and its mutation did not change its subcellular location. Jasmonic acid ( JA ) and salicylic acid ( SA ) accumulation were observed in als1 , and enhanced blast resistance was also observed. The mutation of ALS 1 caused a constitutively activated defence response in als1 . The results of our study imply that ALS 1 participates in a defence response resembling the common SA ‐, JA ‐ and NH 1 ‐mediated defence responses in rice.

Du, D.↗
DOE OSTI2013

Long-Term Probability Distribution of Wind Turbine Planetary Bearing Loads (Poster)

Among the various causes of bearing damage and failure, metal fatigue of the rolling contact surface is the dominant failure mechanism. The fatigue life is associated with the load conditions under which wind turbines operate in the field. Therefore, it is important to understand the long-term distribution of the bearing loads under various environmental conditions. The National Renewable Energy Laboratory's 750-kW Gearbox Reliability Collaborative wind turbine is studied in this work. A decoupled analysis using several computer codes is carried out. The global aero-elastic simulations are performed using HAWC2. The time series of the drivetrain loads and motions from the global dynamic analysis are fed to a drivetrain model in SIMPACK. The time-varying internal pressure distribution along the raceway is obtained analytically. A series of probability distribution functions are then used to fit the long-term statistical distribution at different locations along raceways. The long-term distribution of the bearing raceway loads are estimated under different environmental conditions. Finally, the bearing fatigue lives are calculated.

17 WIND ENERGY↗
DOE OSTI2013

Model Fidelity Study of Dynamic Transient Loads in a Wind Turbine Gearbox: Preprint

Transient events cause high loads in the drivetrain components so measuring and calculating these loads can improve confidence in drivetrain design. This paper studies the Gearbox Reliability Collaborative 750kW wind turbine gearbox response during transient events using a combined experimental and modeling approach. The transient events include emergency shut-downs and start-ups measured during a field testing period in 2009. The drivetrain model is established in the multibody simulation tool Simpack. A detailed study of modeling fidelity required for accurate load prediction is performed and results are compared against measured loads. A high fidelity model that includes shaft and housing flexibility and accurate bearing stiffnesses is important for the higher-speed stage bearing loads. Each of the transient events has different modeling requirements.

17 WIND ENERGY↗
NASA NTRS1992

The Ribosomal Database Project

The Ribosomal Database Project (RDP) complies ribosomal sequences and related data, and redistributes them in aligned and phylogenetically ordered form to its user community. It also offers various software packages for handling, analyzing and displaying sequences. In addition, the RDP offers (or will offer) certain analytic services. At present the project is in an intermediate stage of development.

Non-NASA Center↗