286 research outputs found
Data Driven Chiller Plant Energy Optimization with Domain Knowledge
Refrigeration and chiller optimization is an important and well studied topic
in mechanical engineering, mostly taking advantage of physical models, designed
on top of over-simplified assumptions, over the equipments. Conventional
optimization techniques using physical models make decisions of online
parameter tuning, based on very limited information of hardware specifications
and external conditions, e.g., outdoor weather. In recent years, new generation
of sensors is becoming essential part of new chiller plants, for the first time
allowing the system administrators to continuously monitor the running status
of all equipments in a timely and accurate way. The explosive growth of data
flowing to databases, driven by the increasing analytical power by machine
learning and data mining, unveils new possibilities of data-driven approaches
for real-time chiller plant optimization. This paper presents our research and
industrial experience on the adoption of data models and optimizations on
chiller plant and discusses the lessons learnt from our practice on real world
plants. Instead of employing complex machine learning models, we emphasize the
incorporation of appropriate domain knowledge into data analysis tools, which
turns out to be the key performance improver over state-of-the-art deep
learning techniques by a significant margin. Our empirical evaluation on a real
world chiller plant achieves savings by more than 7% on daily power
consumption.Comment: CIKM2017. Proceedings of the 26th ACM International Conference on
Information and Knowledge Management. 201
LiveVV: Human-Centered Live Volumetric Video Streaming System
Volumetric video has emerged as a prominent medium within the realm of
eXtended Reality (XR) with the advancements in computer graphics and depth
capture hardware. Users can fully immersive themselves in volumetric video with
the ability to switch their viewport in six degree-of-freedom (DOF), including
three rotational dimensions (yaw, pitch, roll) and three translational
dimensions (X, Y, Z). Different from traditional 2D videos that are composed of
pixel matrices, volumetric videos employ point clouds, meshes, or voxels to
represent a volumetric scene, resulting in significantly larger data sizes.
While previous works have successfully achieved volumetric video streaming in
video-on-demand scenarios, the live streaming of volumetric video remains an
unresolved challenge due to the limited network bandwidth and stringent latency
constraints. In this paper, we for the first time propose a holistic live
volumetric video streaming system, LiveVV, which achieves multi-view capture,
scene segmentation \& reuse, adaptive transmission, and rendering. LiveVV
contains multiple lightweight volumetric video capture modules that are capable
of being deployed without prior preparation. To reduce bandwidth consumption,
LiveVV processes static and dynamic volumetric content separately by reusing
static data with low disparity and decimating data with low visual saliency.
Besides, to deal with network fluctuation, LiveVV integrates a volumetric video
adaptive bitrate streaming algorithm (VABR) to enable fluent playback with the
maximum quality of experience. Extensive real-world experiment shows that
LiveVV can achieve live volumetric video streaming at a frame rate of 24 fps
with a latency of less than 350ms
Inhibition of HDAC activity directly reprograms murine embryonic stem cells to trophoblast stem cells
Embryonic stem cells (ESCs) can differentiate into all cell types of the embryonic germ layers. ESCs can also generate totipotent 2C-like cells and trophectodermal cells. However, these latter transitions occur at low frequency due to epigenetic barriers, the nature of which is not fully understood. Here, we show that treating mouse ESCs with sodium butyrate (NaB) increases the population of 2C-like cells and enables direct reprogramming of ESCs into trophoblast stem cells (TSCs) without a transition through a 2C-like state. Mechanistically, NaB inhibits histone deacetylase activities in the LSD1-HDAC1/2 corepressor complex. This increases acetylation levels in the regulatory regions of both 2C- and TSC-specific genes, promoting their expression. In addition, NaB-treated cells acquire the capacity to generate blastocyst-like structures that can develop beyond the implantation stage in vitro and form deciduae in vivo. These results identify how epigenetics restrict the totipotent and trophectoderm fate in mouse ESCs.</p
Effect of Grain Coalescence on Dislocation and Stress Evolution of GaN Films Grown on Nanoscale Patterned Sapphire Substrates
Two types of nucleation layers (NLs), including in-situ low-temperature grown
GaN (LT-GaN) and ex-situ sputtered physical vapor deposition AlN (PVD-AlN), are
applied on cone-shaped nanoscale patterned sapphire substrate (NPSS). The
initial growth process of GaN on these two NLs is comparably investigated by a
series of growth interruptions. The coalescence process of GaN grains is
modulated by adjusting the three-dimensional (3D) temperatures. The results
indicate that higher 3D temperatures reduce the edge dislocation density while
increasing the residual compressive stress in GaN films. Compared to the LT-GaN
NLs, the PVD-AlN NLs effectively resist Ostwald ripening and facilitate the
uniform growth of GaN grains on NPSS. Furthermore, GaN films grown on NPSS with
PVD-AlN NLs exhibit a reduction of over 50% in both screw and edge dislocation
densities compared to those grown on LT-GaN NLs. Additionally, PVD-AlN NLs
result in an increase of about 0.5 GPa in the residual compressive stress
observed in GaN films
Silicon Nanophotonic Waveguides for the Mid-Infrared
It has recently been shown that silicon nanophotonic waveguides can be used
to construct all of the components of a photonic data transmission system on a
single chip. These components can be integrated together with CMOS electronics
to create complex electronic-photonic integrated circuits. It has also emerged
that the high field confinement of silicon nanoscale guides enables exciting
new applications, from chipscale nonlinear optics to biosensors and light-force
activated devices. To date, most of the experiments in silicon waveguides have
been at wavelengths in the near-infrared, ranging from 1.1-2 microns. Here we
show that single-mode silicon nano-waveguides can be used at mid-infrared
wavelengths, in particular at 4.5 microns, or 2222.2 1/cm. This idea has
appeared in theoretical literature, but experimental realization has been
elusive. This result represents the first practical integrated waveguide system
for the mid-infrared in silicon, and enables a range of new applications.Comment: 18 pages, 4 figure
SPI1-induced downregulation of FTO promotes GBM progression by regulating pri-miR-10a processing in an m6A-dependent manner
As one of the most common post-transcriptional modifications of mRNAs and noncoding RNAs, N6-methyladenosine (m6A) modification regulates almost every aspect of RNA metabolism. Evidence indicates that dysregulation of m6A modification and associated proteins contributes to glioblastoma (GBM) progression. However, the function of fat mass and obesity-associated protein (FTO), an m6A demethylase, has not been systematically and comprehensively explored in GBM. Here, we found that decreased FTO expression in clinical specimens correlated with higher glioma grades and poorer clinical outcomes. Functionally, FTO inhibited growth and invasion in GBM cells in vitro and in vivo. Mechanistically, FTO regulated the m6A modification of primary microRNA-10a (pri-miR-10a), which could be recognized by reader HNRNPA2B1, recruiting the microRNA microprocessor complex protein DGCR8 and mediating pri-miR-10a processing. Furthermore, the transcriptional activity of FTO was inhibited by the transcription factor SPI1, which could be specifically disrupted by the SPI1 inhibitor DB2313. Treatment with this inhibitor restored endogenous FTO expression and decreased GBM tumor burden, suggesting that FTO may serve as a novel prognostic indicator and therapeutic molecular target of GBM.publishedVersio
The dual role of glioma exosomal microRNAs: glioma eliminates tumor suppressor miR-1298-5p via exosomes to promote immunosuppressive effects of MDSCs
Clear evidence shows that tumors could secrete microRNAs (miRNAs) via exosomes to modulate the tumor microenvironment (TME). However, the mechanisms sorting specific miRNAs into exosomes are still unclear. In order to study the biological function and characterization of exosomal miRNAs, we performed whole-transcriptome sequencing in 59 patients’ whole-course cerebrospinal fluid (CSF) small extracellular vesicles (sEV) and matched glioma tissue samples. The results demonstrate that miRNAs could be divided into exosome-enriched miRNAs (ExomiRNAs) and intracellular-retained miRNAs (CLmiRNAs), and exosome-enriched miRNAs generally play a dual role. Among them, miR-1298-5p was enriched in CSF exosomes and suppressed glioma progression in vitro and vivo experiments. Interestingly, exosomal miR-1298-5p could promote the immunosuppressive effects of myeloid-derived suppressor cells (MDSCs) to facilitate glioma. Therefore, we found miR-1298-5p had different effects on glioma cells and MDSCs. Mechanically, downstream signaling pathway analyses showed that miR-1298-5p plays distinct roles in glioma cells and MDSCs via targeting SETD7 and MSH2, respectively. Moreover, reverse verification was performed on the intracellular-retained miRNA miR-9-5p. Thus, we confirmed that tumor-suppressive miRNAs in glioma cells could be eliminated through exosomes and target tumor-associated immune cells to induce tumor-promoting phenotypes. Glioma could get double benefit from it. These findings uncover the mechanisms that glioma selectively sorts miRNAs into exosomes and modulates tumor immunity.publishedVersio
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