Evaluating and Improving the Depth Accuracy of Kinect for Windows v2

Microsoft Kinect sensor has been widely used in many applications since the launch of its first version. Recently, Microsoft released a new version of Kinect sensor with improved hardware. However, the accuracy assessment of the sensor remains to be answered. In this paper, we measure the depth accuracy of the newly released Kinect v2 depth sensor, and obtain a cone model to illustrate its accuracy distribution. We then evaluate the variance of the captured depth values by depth entropy. In addition, we propose a trilateration method to improve the depth accuracy with multiple Kinects simultaneously. The experimental results are provided to ascertain the proposed model and method

H2TNE: Temporal Heterogeneous Information Network Embedding in Hyperbolic Spaces

Temporal heterogeneous information network (temporal HIN) embedding, aiming to represent various types of nodes of different timestamps into low dimensional spaces while preserving structural and semantic information, is of vital importance in diverse real-life tasks. Researchers have made great efforts on temporal HIN embedding in Euclidean spaces and got some considerable achievements. However, there is always a fundamental conflict that many real-world networks show hierarchical property and power-law distribution, and are not isometric of Euclidean spaces. Recently, representation learning in hyperbolic spaces has been proved to be valid for data with hierarchical and power-law structure. Inspired by this character, we propose a hyperbolic heterogeneous temporal network embedding (H2TNE) model for temporal HINs. Specifically, we leverage a temporally and heterogeneously double-constrained random walk strategy to capture the structural and semantic information, and then calculate the embedding by exploiting hyperbolic distance in proximity measurement. Experimental results show that our method has superior performance on temporal link prediction and node classification compared with SOTA models.Comment: arXiv admin note: text overlap with arXiv:1705.08039 by other author

Upregulation of Toll-like receptor (TLR) expression and release of cytokines from P815 mast cells by GM-CSF

<p>Abstract</p> <p>Backgroud</p> <p>Recently, mast cells have been recognized to express several Toll-like receptors (TLRs) on their membrane surfaces, and granulocyte-macrophage colony-stimulating factor (GM-CSF) was reported to be able to alter expression of TLRs and cytokine production in neutrophils. However, whether GM-CSF modulates the expression of TLR and cytokine production in mast cells is not clear.</p> <p>Results</p> <p>Using flow cytometry and real time PCR techniques, we found that GM-CSF upregulated expression of TLR3 and TLR7 in P815 cells in a concentration dependent manner. GM-CSF also provoked approximately up to 2.4 and 2.3 fold increase in IL-13 and IL-6 release from P815 cells, respectively following 16 h incubation. GM-CSF induced IL-13 secretion, TLR3 and TLR7 expression appeared to be through activation of mitogen-activated protein kinase (MAPK) and phosphotidylinositol 3-kinase (PI3K)/Akt signaling pathways, whereas GM-CSF elicited IL-6 release seemed via Akt signaling pathway. At 10 ng/ml, GM-CSF significantly enhanced R-848-induced IL-6 release from P815 cells.</p> <p>Conclusion</p> <p>The ability of GM-CSF in modulation of expression of TLR3 and TLR7 in P815 mast cells and in stimulation of IL-13 and IL-6 release from P815 mast cells in vitro suggests that GM-CSF might play an important role in enhancing the innate immune responses of mast cell to viral infection</p

Thermo-economic analysis of a novel partial cascade organic-steam Rankine cycle

Conventional heat batteries and concentrated solar power systems adopt subcritical steam Rankine cycles (SRCs) to avoid the technical challenges of supercritical cycles. The water evaporation temperature of 310–337 °C and live steam pressure of 10–14 MPa limit the cycle efficiency (around 42%). This paper proposes a novel partial cascade organic-steam Rankine cycle (ORC-SRC) system to increase the fluid evaporation temperature and thermal efficiency. The ORC-SRC uses a mixture of biphenyl and diphenyl oxide as the top cycle fluid. The mixture absorbs heat from the molten salts and evaporates at about 400 °C to drive a turbine, and then the exhaust vapor releases heat to the bottom SRC. The ORC contributes to saturated steam generation, and molten salts supply the rest heat to the SRC through the steam superheater and reheater. The fundamentals of the system are illustrated, and mathematical models are built. Thermo-economic performance of the system is investigated. The results show that the proposed system significantly increases the average temperature of the power fluid in the heating process, leading to a maximum cycle efficiency of 45.3%. Meanwhile, the moderate live steam pressure of 7.44 MPa in the SRC reduces the leakage loss of the high-pressure turbine and equipment costs. Despite a smaller temperature drop of molten salts during discharge, the equivalent payback period of the ORC-SRC is within 4 years

Analysis of a direct vapor generation system using cascade steam-organic Rankine cycle and two-tank oil storage

A direct vapor generation solar power system using cascade steam-organic Rankine cycle and two-stage oil tanks is proposed. It offers a significantly enlarged storage capacity due to the unique discharge operation mode. Synthetic oil Therminol® VP-1 is used as the heat carrier and storage medium. Compared with the direct steam generation system, the steam turbine inlet temperature is elevated from 270 °C to 311 °C. Thermodynamic analysis indicates that the optimal equivalent heat-to-power conversion efficiency (ηeq,opt) is 27.91% when benzene is used as the bottom fluid and the mass of oil is 1000 tonnes. ηeq,opt is raised by 7.72–11.60% for the selected four organic fluids as compared with the direct steam generation type. The temperature drop of oil during discharge can reach about 280 °C. Economic studies demonstrate that the proposed system is more cost-effective. Its equivalent payback period is less than 5 years for a 10 MW system with 2000 tonnes of oil. Further investigation shows that it is also more advantageous than a conventional thermal oil-based indirect solar power system due to the cost reduction in heat storage

An innovative approach to recovery of fluctuating industrial exhaust heat sources using cascade Rankine cycle and two-stage accumulators

The fluctuating property of the heat source is a technical obstacle of waste heat recovery, which leads to part-load operation and reduced economics. This work presents a novel system to mitigate the fluctuations by using steam-organic Rankine cycles (RC-ORC) and two-stage steam accumulators. The system can switch between isothermal heat storage and discharge simply by the regulation of water mass flow (m ) from the low-temperature accumulator (LTA) to the high-temperature accumulator (HTA). In the heat charge mode, m rises when the inlet temperature or mass flow of the heat source increases. The water level of the HTA elevates. Analogously, in the heat discharge mode, m decreases and more water accumulates in the LTA. The RC-ORC operates under the rated condition consistently through the unique structural design. The fundamentals and features of the system are illustrated. Given two typical heat source conditions, the fluctuations in thermal efficiencies are minor (15.63–15.84% and 19.57–19.70%). Thermo-economic estimation of the tanks indicates that the steel cost is roughly 1306 $and 432$, respectively. Compared with the single-stage ORC using stream control, the normalized investment cost (NIC) is reduced by 888–925 $/kW. 2 2