131 research outputs found
Study on Application of Solar Water Heat Pump for Building in China
AbstractIn order to solve the issue of applicability of solar water source heat pump for building, this article analyzes the load characteristics in different climate regions based on the three typical cities which are Harbin, Beijing, Shanghai, then sets up system mathematical models, uses the eQUEST set up the building model and puts the model into TRNSYS to do the optimization calculation. According to the theory of Life Cycle Assessment, this article analyzes the applicability of solar water source heat pump for building by taking feasibility, energy saving property, economy and environmental protection property as technical index and get the conclusion that the applicability of solar water source heat pump for building in severe cold region and cold region is well and the environmental benefit is obvious
New Stability Criterion for Discrete-Time Genetic Regulatory Networks with Time-Varying Delays and Stochastic Disturbances
We propose an improved stability condition for a class of discrete-time genetic regulatory networks (GRNs) with interval time-varying delays and stochastic disturbances. By choosing an augmented novel Lyapunov-Krasovskii functional which contains some triple summation terms, a less conservative sufficient condition is obtained in terms of linear matrix inequalities (LMIs) by using the combination of the lower bound lemma, the discrete-time Jensen inequality, and the free-weighting matrix method. It is shown that the proposed results can be readily solved by using the Matlab software. Finally, two numerical examples are provided to illustrate the effectiveness and advantages of the theoretical results
A new model-based approach for power plant Tube-ball mill condition monitoring and fault detection
AbstractWith the fast growth in intermittent renewable power generation, unprecedented demands for power plant operation flexibility have posed new challenges to the ageing conventional power plants in the UK. Adding biomass to coal for co-fired power generation has become widely implemented practices in order to meet the emission regulation targets. These have impacted the coal mill and power plant operation safety and reliability. The Vertical Spindle mill model was developed through the authors’ work before 2007. From then, the new research progress has been made in modelling and condition monitoring for Tube-ball mills and is reported in the paper. A mathematical model for Tube-ball milling process is developed by applying engineering principles combined with model unknown parameter identifications using a computational intelligent algorithm. The model describes the whole milling process from the mill idle status, start-up to normal grinding and shut-down. The model is verified using on-site measurement data and on-line test. The on-line model is used for mill condition monitoring in two ways: (i) to compare the predicted and measured mill output pressure and temperatures and to raise alarms if there are big discrepancies; and (ii) to monitor the mill model parameter variation patterns which detect the potential faults and mill malfunctions
The Tianlin Mission: a 6m UV/Opt/IR space telescope to explore the habitable worlds and the universe
[Abridged] It is expected that the ongoing and future space-borne planet
survey missions including TESS, PLATO, and Earth 2.0 will detect thousands of
small to medium-sized planets via the transit technique, including over a
hundred habitable terrestrial rocky planets. To conduct a detailed study of
these terrestrial planets, particularly the cool ones with wide orbits, the
exoplanet community has proposed various follow-up missions. The currently
proposed ESA mission ARIEL is capable of characterization of planets down to
warm super-Earths mainly using transmission spectroscopy. The NASA 6m
UV/Opt/NIR mission proposed in the Astro2020 Decadal Survey may further tackle
down to habitable rocky planets, and is expected to launch around 2045. In the
meanwhile, China is funding a concept study of a 6-m class space telescope
named Tianlin (A UV/Opt/NIR Large Aperture Space Telescope) that aims to start
its operation within the next 10-15 years and last for 5+ years. Tianlin will
be primarily aimed to the discovery and characterization of rocky planets in
the habitable zones (HZ) around nearby stars and to search for potential
biosignatures mainly using the direct imaging method. Transmission and emission
spectroscopy at moderate to high resolution will be carried out as well on a
population of exoplanets to strengthen the understanding of the formation and
evolution of exoplanets. It will also carry out in-depth studies of the cosmic
web and early galaxies, and constrain the nature of the dark matter and dark
energy. We describe briefly the primary scientific motivations and main
technical considerations based on our preliminary simulation results. We find
that a monolithic off-axis space telescope with a primary mirror diameter
larger than 6m equipped with a high contrast chronograph can identify water in
the atmosphere of a habitable-zone Earth-like planet around a Sun-like star.Comment: 15 pages, 5 figures, accepted for publication in RAA and is available
onlin
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