Simulation of the Melting Process of Ice Slurry for Energy Storage Using a Two-Fluid Lattice Boltzmann Method

Ice slurry can be used as the thermal storage media in latent cool storage systems for both residential and commercial buildings. This paper presents the investigation of the phase change characteristics of the ice slurry using a two-fluid Lattice Boltzmann Method (TFLBM). The melting and migration processes of the ice slurry are simulated by improving the equilibrium distribution function and matching the relevant parameters such as the kinetic viscosity of ice particle cluster and cross-collision coefficient. The sensitivity analysis of the ice slurry viscosity and cross-collision coefficient are achieved through six numerical experiments, and the ice melting in the internal-melt ice-on-coil thermal storage device is then calculated. The results could be potentially used to guide the design of the ice slurry for cooling both residential and commercial buildings

Operation Mechanism of the Driving Force System of Ecosystem of Cyber-society Based on the System Dynamics

Operation of the driving force system of Ecosystem of Cyber-society needs a scientific mechanism of intervention and regulation to solve the integration problem of a variety of organizations and forces within the Ecosystem of Cyber-society, shorten the process from uncoordination to coordination, promote the orderly operation of the driving force system of Ecosystem of Cyber-society, make the system play a strong force, in order to promote the formation and rapid development of Ecosystem of Cyber-society. We analyze the driving force system of Ecosystem of Cyber-society using the theory of System Dynamics and propose a theoretical framework, and then present its operation mechanism systematically

Activity Recognition and Prediction in Real Homes

In this paper, we present work in progress on activity recognition and prediction in real homes using either binary sensor data or depth video data. We present our field trial and set-up for collecting and storing the data, our methods, and our current results. We compare the accuracy of predicting the next binary sensor event using probabilistic methods and Long Short-Term Memory (LSTM) networks, include the time information to improve prediction accuracy, as well as predict both the next sensor event and its mean time of occurrence using one LSTM model. We investigate transfer learning between apartments and show that it is possible to pre-train the model with data from other apartments and achieve good accuracy in a new apartment straight away. In addition, we present preliminary results from activity recognition using low-resolution depth video data from seven apartments, and classify four activities - no movement, standing up, sitting down, and TV interaction - by using a relatively simple processing method where we apply an Infinite Impulse Response (IIR) filter to extract movements from the frames prior to feeding them to a convolutional LSTM network for the classification.Comment: 12 pages, Symposium of the Norwegian AI Society NAIS 201

Solvent-Induced Crystallization Method for High-Performance and Long-Term Stability Flexible Perovskite Photodetectors

Herein, we report a novel solvent-induced fabrication method to synthesize a perovskite thin film on flexible substrates. The high-quality CH3NH3PbI3 (MAPbI3) thin film is successfully fabricated, which is applied to prepare the stable flexible photodetector (PD). Compared with the reported results, this method achieved a low-temperature and low-cost perovskite thin film fabrication process on a flexible substrate. The constructed MAPbI3 layer possesses the advantages of being highly crystalline, uniform, and compact in a large area. The flexible PD based on the as-prepared perovskite thin film exhibits excellent performance and long-term stability. The EQE and R of the flexible PDs reached 8 × 102% and 3.6 A/W, respectively. At the same time, the flexible PDs still showed superior stability and high performance after 15 days of continuous working. The presented high-quality perovskite thin-film fabrication method and high-performance flexible perovskite PDs are expected for application in the development of novel optoelectronic devices

Macro-Micro Failure Mechanisms and Damage Modeling of a Bolted Rock Joint

The anchoring mechanism of a bolted joint subjected to a shear load was investigated using a bilinear constitutive model via the inner-embedded FISH language of particle flow code based on the discrete element method. The influences of the anchoring system on the macro-/micromechanical response were studied by varying the inclination angle of the bolt. The results indicate a clear relationship between the mechanical response of a bolted rock joint and the mechanical properties of the anchoring angle. By optimizing the anchorage angle, the peak strength can be increased by nearly 50% relative to that at an anchorage angle of 90°. The optimal anchorage angle ranges from 45° to 75°. The damage mechanism at the optimal anchorage angle joint is revealed from a macroscopic mechanical perspective. The concentration of the contact force between disks will appear in the joint and around the bolt, resulting in crack initiation. These cracks are mainly tensile cracks, which are consistent with the formation mechanism for compression-induced tensile cracks. Therefore, the macroscopic peak shear stress in the joint and the microscopic damage to the anchoring system should be considered when determining the optimal anchoring angle to reinforce a jointed rock mass

Cardiac biophysical detailed synergetic modality rendering and visible correlation

The heart is a vital organ in the human body. Research and treatment for the heart have made remarkable progress, and the functional mechanisms of the heart have been simulated and rendered through the construction of relevant models. The current methods for rendering cardiac functional mechanisms only consider one type of modality, which means they cannot show how different types of modality, such as physical and physiological, work together. To realistically represent the three-dimensional synergetic biological modality of the heart, this paper proposes a WebGL-based cardiac synergetic modality rendering framework to visualize the cardiac physical volume data and present synergetic correspondence rendering of the cardiac electrophysiological modality. By constructing the biological detailed interactive histogram, users can implement local details rendering for the heart, which could reveal the cardiac biology details more clearly. We also present cardiac physical-physiological correlation visualization to explore cardiac biological association characteristics. Experimental results show that the proposed framework can provide favorable cardiac biological detailed synergetic modality rendering results in terms of both effectiveness and efficiency. Compared with existing methods, the framework can facilitate the study of the internal mechanism of the heart and subsequently deduce the process of initiation, development, and transformation from a healthy heart to an ill one, and thereby improve the diagnosis and treatment of cardiac disorders

A sulfotransferase specific to N-21 of gonyautoxin 2/3 from crude enzyme extraction of toxic dinoflagellate Alexandrium tamarense CI01

[Abstract]:Sulfotransferase (ST) is the first enzyme discovered in association with paralytic shellfish poisoning (PSP) toxin biosynthesis in toxic dinoflagellates. This study investigates the ST activity in crude enzyme extraction of a toxic dinoflagellate species, Alexandrium tamarense CI01. The results show that crude enzyme can transfer a sulfate group from 3’-phosphoadenosine 5’-phosphosulfate (PAPS) to N-21 in the carbamoyl group of gonyautoxin 2/3 (GTX2/3) to produce C1/C2, but is inactive toward STX to produce GTX5. The crude enzyme is optimally active at pH 6.0 and 15°C. The activity is enhanced by Co2+, Mg2+, Mn2+ and Ca2+ individually, but is inhibited by Cu2+. Moreover, the activity shows no difference when various sulfur compounds are used as sulfate donors. These results demonstrate that the ST specific to GTX2/3 is present in the cells of A. tamarense CI01 and is involved in PSP toxin biosynthesis. In addition, the ST from different dinoflagellates is species-specific, which explains well the various biosynthesis pathways of the PSP toxins in toxic dinoflagellates.Supported by the National Natural Science Foundation of China (No.40376032) and the Ministry of Science and Technology of the People’s Republic of China (No.2001CB409700)

Research on the characteristics of CO2-water interface and the law of dissolution and mass transfer under the condition of carbon sequestration in goaf

As an important negative carbon technology to solve the carbon emission problem in the coal industry, the CO2 sequestration in the mine goaf has a wide application prospect in the secondary utilization of waste resources in the goaf and the capture and storage of CO2. In this study, the influence of different temperatures and pressures, formation water salinity and cationic solution type on the interfacial tension (IFT) of CO2-formation water system was investigated by using in-situ interfacial tension meter. The gas-liquid interface diffusion effect of CO2 injection into water-bearing coal rock mass was clarified. The equation of state (SAFT-LJ equation of state) based on statistical association theory combined with the Lanner-Jones potential energy model and density gradient theory (DGT) were combined to predict the theoretical value of IFT. Using a self-developed geological sequestration and geochemical reaction simulation experimental platform, various exploratory experiments were conducted to investigate the solubility of CO2 under the same conditions. The characteristics of CO2 solubility variation in the reservoir environment of the goaf were obtained, and the corresponding theoretical values of CO2 solubility were calculated using the D-S model. The experimental results show that when the ambient temperature is constant, the reservoir pressure in the goaf is linearly negatively correlated with the IFT value. As the reservoir temperature increases, the IFT value increases correspondingly, but the change range is small. Under constant temperature and pressure conditions, there is a positive correlation between salinity and IFT value. Within the scope of this experiment, low pressure, high temperature, and high salinity promote an increase in the IFT value. The IFT values between CO2-salt solutions show an increasing trend with the increasing valence of cations (K+ < Na+ < Ca2+ < Mg2+). The pressure of the depleted reservoir is positively correlated with the CO2 solubility. When the temperature is 25 °C and under conditions of pure water, as the pressure increases from 0.5 MPa to 2.5 MPa, the corresponding CO2 solubility increases from 0.1627 mol/kg to 0.7141 mol/kg. The CO2 solubility decreases with the increases of temperature and salinity. Under the same concentration, monovalent cation solutions (NaCl, KCl) can dissolve more CO2 than divalent cation solutions (CaCl2, MgCl2). The free phase CO2 injected into the goaf overcomes the interfacial tension and breaks the geochemical balance of the goaf strata through diffusion and dissolution mass transfer. By clarifying the influence of reservoir temperature and pressure conditions and goaf water environment on IFT value and CO2 solubility, the gas-liquid interface effect and dissolution mass transfer mechanism of CO2-formation water are clarified, so as to provide a theoretical basis for the safety and evaluation of CO2 sequestration in the closed mine goaf