682 research outputs found
A state-space based method to predict thermal performance of pipeembedded double skin façade: case study in Guangzhou
Pipe-embedded double skin facade, which arranges pipes in shading device, is an alternative to reduce indoor demand and save energy. To simulate annual performance of this system, a simplified approach based on optical and thermal property is proposed at first, in which dynamic performance is acquired through state-space method. Then the model is validated with former investigation and shows good accuracy. Indoor room temperature with the pipe-embedded double skin façade is analyzed under different types of room in Guangzhou at last. Results show that the pipe-embedded double skin façade could guarantee a barely satisfactory indoor environment where indoor heat gain is small in most time. Besides, superiority would be obvious when solar radiation is strong, indicating the applicability in some typical region with abundant sunshine
Multi-Path Bound for DAG Tasks
This paper studies the response time bound of a DAG (directed acyclic graph)
task. Recently, the idea of using multiple paths to bound the response time of
a DAG task, instead of using a single longest path in previous results, was
proposed and leads to the so-called multi-path bound. Multi-path bounds can
greatly reduce the response time bound and significantly improve the
schedulability of DAG tasks. This paper derives a new multi-path bound and
proposes an optimal algorithm to compute this bound. We further present a
systematic analysis on the dominance and the sustainability of three existing
multi-path bounds and the proposed multi-path bound. Our bound theoretically
dominates and empirically outperforms all existing multi-path bounds. What's
more, the proposed bound is the only multi-path bound that is proved to be
self-sustainable
Biomarkers for Hepatocellular Carcinoma
Hepatocellular carcinoma (HCC) is the third leading cause of cancer deaths worldwide. The HCC diagnosis is usually achieved by biomarkers, which can also help in prognosis prediction. Furthermore, it might represent certain therapeutic interventions through some combinations of biomarkers. Here, we review on our current understanding of HCC biomarkers
AI based Robot Safe Learning and Control
Introduction This open access book mainly focuses on the safe control of robot manipulators. The control schemes are mainly developed based on dynamic neural network, which is an important theoretical branch of deep reinforcement learning. In order to enhance the safety performance of robot systems, the control strategies include adaptive tracking control for robots with model uncertainties, compliance control in uncertain environments, obstacle avoidance in dynamic workspace. The idea for this book on solving safe control of robot arms was conceived during the industrial applications and the research discussion in the laboratory. Most of the materials in this book are derived from the authors’ papers published in journals, such as IEEE Transactions on Industrial Electronics, neurocomputing, etc. This book can be used as a reference book for researcher and designer of the robotic systems and AI based controllers, and can also be used as a reference book for senior undergraduate and graduate students in colleges and universities
Rate-Splitting with Hybrid Messages: DoF Analysis of the Two-User MIMO Broadcast Channel with Imperfect CSIT
Most of the existing research on degrees-of-freedom (DoF) with imperfect
channel state information at the transmitter (CSIT) assume the messages are
private, which may not reflect reality as the two receivers can request the
same content. To overcome this limitation, we consider hybrid private and
common messages. We characterize the optimal DoF region for the two-user
multiple-input multiple-output (MIMO) broadcast channel with hybrid messages
and imperfect CSIT. We establish a three-step procedure for the DoF converse to
exploit the utmost possible relaxation. For the DoF achievability, since the
DoF region has a specific three-dimensional structure w.r.t. antenna
configurations and CSIT qualities, by dividing CSIT qualities into cases, we
check the existence of corner point solutions, and then design a hybrid
messages-aware rate-splitting scheme to achieve them. Besides, we show that to
achieve the strictly positive corner points, it is unnecessary to split the
private messages into unicast and multicast parts because the allocated power
for the multicast part should be zero. This implies that adding a common
message can mitigate the rate-splitting complexity of private messages.Comment: 32page
Investigation of the mechanisms on the abnormal features observed in thermal-mechanical testing of AA6061 under extrusion conditions
Hot extrusion is the most common forming technology for aluminium alloy AA6061 due to its good extrudability, and thus it is important to study its high-temperature deformation characteristics. In this study, three abnormal features are observed in thermal-mechanical testing under extrusion conditions of AA6061 specimens from one billet: 1) Two types of specimens with grey-coloured surface or silver-coloured surface appear after solution heat treatment (SHT); 2) The silver-coloured specimens show orange peel surface after hot compression tests; 3) The silver-coloured specimens have lower flow stresses than the grey-coloured specimens. This paper investigates the mechanisms behind the above abnormal features. A laser scanning confocal microscope is employed to examine the surface roughening, and electron back scatter diffraction is used to characterise microstructural changes. It is found that the main causes of the above behaviour are due to different initial grain morphologies and the evolution of dislocation density after SHT. The silver-coloured specimens initially have smaller columnar grains which undergo recrystallisation and extensive growth during SHT, and the dislocation density decreases significantly, leading to orange peel defect and low flow stress during compression tests, respectively. The grey-coloured specimens have larger columnar grains. After SHT, some grains undergo recrystallisation, but others still maintain the shape of the large columnar grains, and the dislocation density does not change significantly, resulting in surface oxidation with smooth surface after thermal-mechanical testing and 10–25 MPa (30–50%) higher flow stress compared to the silver-coloured specimens in compression tests
DETC2005-84370 STUDY ON THE SENSITIVITY OF CONTROLLABLE PARAMETERS IN AN ACTIVE VIBRATION ISOLATION SYSTEM OF AIR SPRING WITH RUBBER BELLOW
ABSTRACT The characteristics of control parameters of air spring with rubber bellow are analyzed through finite element method and thermodynamic equation respectively. The analysis results indicate that the vertical stiffness of air spring is sensitive to the varying of vertical displacement and volume, and nonlinearly varies with vertical displacement. When the air spring is pressed down or pulled up under the exterior excitation, the height of air spring can be controlled to keep stable through adjusting the volume of air spring by the use of hydraulic transformer
Inhibition of autophagy enhances SMI-4a-induced growth inhibition and apoptosis of melanoma cells
Purpose: To investigate the exact role of the proviral integration site for Moloney murine leukemia virus-1 (PIM-1) on autophagy as well as the underlying molecular mechanisms in melanoma.Methods: mRNA expression levels in A375 and G361 human melanoma cell lines were measured using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Enzyme-linked immunosorbent (ELISA) and western blotting assays were applied to determine protein expression levels, while cell viability was evaluated using Cell Counting Kit 8 and colony formation assay. Flow cytometric analysis and caspase 3/7 activity assay were used to assess apoptosis.Results: The results show that pharmacological inhibition of PIM-1 with its potent inhibitor (SMI-4a) suppressed cell viability and induced apoptosis in melanoma cell lines A375 and G361. SMI-4a also induced autophagy through inhibition of the phosphoinositide 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) axis in melanoma cells. Furthermore, chloroquine, an inhibitor of autophagy, potentiated the SMI-4a-induced inhibition of tumour growth and promotion of apoptosis in melanoma cells in vitro and in vivo.Conclusions: These results suggest that SMI-4a induces protective autophagy via PI3K/AKT/mTOR signaling pathway in melanoma cells. Thus, a combination of SMI-4a and an inhibitor of autophagy might be a novel approach to melanoma therapy.Keywords: Apoptosis, Autophagy, Cell viability, Melanoma, PIM-1, SMI-4
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