80 research outputs found
D-Tunes: Configuration Engine for Geo-Replicated Cloud Storage
When developing a web-based application, developers are facing stringent requirements to balance the latency, scalability and availability for their cloud database. Application developers need a specific replication configuration strategy based on the requirement of their application. To deal with this problem, some geo-replicated cloud strategy systems have emerged recently, like Cassandra. This project serves to design a web tool that can help configure the best replication strategies for geo-distributed data stores, which uses quorum-based protocols. Currently, our web tool D-Tunes, require a minimum input from users and generate specific scripts based on the inputs user provided. The program running these scripts can output a text result and also map a figure showing the recommended replication strategy. The results of D-Tunes recommend the best replication strategies including the number of replicas, the location of replicas and read/write quorum size. Our web-tool also generates the applicable strategy, which is a simulation of the real experiment on EC2 and Probe test-bed with Cassandra system. In conclusion, this project has successfully provides cloud application developers a strategy of data-store configuration and has contributes to the ongoing research on cloud computing for Cassandra based solution
“Open space” integrated mangrove intelligent monitoring platform based on the Internet of Things
In order to comprehensively promote mangrove restoration, this paper developed a set of “open space” integrated mangrove
intelligent monitoring platform based on the Internet of Things, in order to solve the problems of traditional mangrove monitoring
technology, such as simple means and small scale. The platform built LoRa Mesh AD hoc network and NB-IoT Internet of things to collect
and transmit mangrove wetland environmental data, developed the upper computer website and the lower computer control system for real_x005ftime monitoring of environmental sensor data, and carried out imaging hyperspectral load with UAV to collect mangrove plant species
and distribution and perform spectral analysis. It aims to use information technology to help the construction of ecological civilization,
and contribute to fully supporting Zhanjiang to build a “mangrove city”. The test results show that the data transmission is normal, the
hyperspectral image picture is clear, the PC analysis is complete, the abnormal environmental data alarm is accurate and rapid, and the
control system responds in time
Liver organoids: a promising three-dimensional model for insights and innovations in tumor progression and precision medicine of liver cancer
Primary liver cancer (PLC) is one type of cancer with high incidence rate and high mortality rate in the worldwide. Systemic therapy is the major treatment for PLC, including surgical resection, immunotherapy and targeted therapy. However, mainly due to the heterogeneity of tumors, responses to the above drug therapy differ from person to person, indicating the urgent needs for personalized treatment for PLC. Organoids are 3D models derived from adult liver tissues or pluripotent stem cells. Based on the ability to recapitulate the genetic and functional features of in vivo tissues, organoids have assisted biomedical research to make tremendous progress in understanding disease origin, progression and treatment strategies since their invention and application. In liver cancer research, liver organoids contribute greatly to reflecting the heterogeneity of liver cancer and restoring tumor microenvironment (TME) by co-organizing tumor vasculature and stromal components in vitro. Therefore, they provide a promising platform for further investigation into the biology of liver cancer, drug screening and precision medicine for PLC. In this review, we discuss the recent advances of liver organoids in liver cancer, in terms of generation methods, application in precision medicine and TME modeling
A method and system for unified authentication management and control of power secondary equipment based on blockchain
Blockchain technology is an advanced database mechanism that allows transparent sharing of information across corporate networks. By analyzing the insufficiency and improvement plan of the operation and maintenance safety management of power secondary equipment, it is proposed to use the operation and maintenance management and control system to select EOS as the underlying scheme of the blockchain, and discuss it based on a trusted blockchain network system
Ultra-low threshold continuous-wave quantum dot mini-BIC lasers
Highly compact lasers with ultra-low threshold and single-mode continuous
wave (CW) operation have been a long sought-after component for photonic
integrated circuits (PICs). Photonic bound states in the continuum (BICs), due
to their excellent ability of trapping light and enhancing light-matter
interaction, have been investigated in lasing configurations combining various
BIC cavities and optical gain materials. However, the realization of BIC laser
with a highly compact size and an ultra-low CW threshold has remained elusive.
We demonstrate room temperature CW BIC lasers in the 1310 nm O-band wavelength
range, by fabricating a miniaturized BIC cavity in an InAs/GaAs epitaxial
quantum dot (QD) gain membrane. By enabling effective trapping of both light
and carriers in all three dimensions, ultra-low threshold of 12 {\mu}W (0.052
kW/cm^2) is achieved. Single-mode lasing is also realized in cavities as small
as only 5*5 unit-cells (~2.5*2.5 {\mu}m^2 cavity size) with a mode volume of
1.16({\lambda}/n)^3. With its advantages in terms of a small footprint,
ultralow power consumption, robustness of fabrication and adaptability for
integration, the mini-BIC lasers offer a perspective light source for future
PICs aimed at high-capacity optical communications, sensing and quantum
information
Long-term exposure to road traffic noise and incident heart failure: evidence from UK Biobank
Background
Evidence on road traffic noise and heart failure (HF) is limited, and little is known on the potential mediation roles of acute myocardial infarction (AMI), hypertension, or diabetes.
Objectives
The purpose of this study was to evaluate the impacts of long-term road traffic noise exposure on the risk of incident HF considering air pollution, and explore the mediations of the previously mentioned diseases.
Methods
This prospective study included 424,767 participants without HF at baseline in UK Biobank. The residential-level noise and air pollution exposure was estimated, and the incident HF was identified through linkages with medical records. Cox proportional hazard models were used to estimate HRs. Furthermore, time-dependent mediation was performed.
Results
During a median 12.5 years of follow-up, 12,817 incident HF were ascertained. The HRs were 1.08 (95% CI: 1.00-1.16) per 10 dB[A] increase in weighted average 24-hour road traffic noise level (Lden), and 1.15 (95% CI: 1.02-1.31) for exposure to Lden >65dB[A] compared with the reference category (Lden ≤55dB[A]), respectively. Furthermore, the strongest combined effects were found in those with both high exposures to road traffic noise and air pollution including fine particles and nitrogen dioxide. Prior AMI before HF within 2 years’ time interval mediated 12.5% of the association of road traffic noise with HF.
Conclusions
More attention should be paid and a preventive strategy should be considered to alleviate the disease burden of HF related to road traffic noise exposure, especially in participants who survived AMI and developed HF within 2 years
Tunable quantum dots in monolithic Fabry-Perot microcavities for high-performance single-photon sources
Cavity-enhanced single quantum dots (QDs) are the main approach towards
ultra-high-performance solid-state quantum light sources for scalable photonic
quantum technologies. Nevertheless, harnessing the Purcell effect requires
precise spectral and spatial alignment of the QDs' emission with the cavity
mode, which is challenging for most cavities. Here we have successfully
integrated miniaturized Fabry-Perot microcavities with a piezoelectric
actuator, and demonstrated a bright single photon source derived from a
deterministically coupled QD within this microcavity. Leveraging the
cavity-membrane structures, we have achieved large spectral-tunability via
strain tuning. On resonance, we have obtained a high Purcell factor of
approximately 9. The source delivers single photons with simultaneous high
extraction efficiency of 0.58, high purity of 0.956(2) and high
indistinguishability of 0.922(4). Together with a small footprint, our scheme
facilitates the scalable integration of indistinguishable quantum light sources
on-chip, and therefore removes a major barrier to the solid-state quantum
information platforms based on QDs.Comment: 12 pages, 4 figure
Metasurface-based Spectral Convolutional Neural Network for Matter Meta-imaging
Convolutional neural networks (CNNs) are representative models of artificial
neural networks (ANNs), that form the backbone of modern computer vision.
However, the considerable power consumption and limited computing speed of
electrical computing platforms restrict further development of CNNs. Optical
neural networks are considered the next-generation physical implementations of
ANNs to break the bottleneck. This study proposes a spectral convolutional
neural network (SCNN) with the function of matter meta-imaging, namely
identifying the composition of matter and mapping its distribution in space.
This SCNN includes an optical convolutional layer (OCL) and a reconfigurable
electrical backend. The OCL is implemented by integrating very large-scale,
pixel-aligned metasurfaces on a CMOS image sensor, which accepts 3D raw
datacubes of natural images, containing two-spatial and one-spectral
dimensions, at megapixels directly as input to realize the matter meta-imaging.
This unique optoelectronic framework empowers in-sensor optical analog
computing at extremely high energy efficiency eliminating the need for coherent
light sources and greatly reducing the computing load of the electrical
backend. We employed the SCNN framework on several real-world complex tasks. It
achieved accuracies of 96.4% and 100% for pathological diagnosis and real-time
face anti-spoofing at video rate, respectively. The SCNN framework, with an
unprecedented new function of substance identification, provides a feasible
optoelectronic and integrated optical CNN implementation for edge devices or
cellphones with limited computing capabilities, facilitating diverse
applications, such as intelligent robotics, industrial automation, medical
diagnosis, and astronomy
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