122 research outputs found
NIPD: A Federated Learning Person Detection Benchmark Based on Real-World Non-IID Data
Federated learning (FL), a privacy-preserving distributed machine learning,
has been rapidly applied in wireless communication networks. FL enables
Internet of Things (IoT) clients to obtain well-trained models while preventing
privacy leakage. Person detection can be deployed on edge devices with limited
computing power if combined with FL to process the video data directly at the
edge. However, due to the different hardware and deployment scenarios of
different cameras, the data collected by the camera present non-independent and
identically distributed (non-IID), and the global model derived from FL
aggregation is less effective. Meanwhile, existing research lacks public data
set for real-world FL object detection, which is not conducive to studying the
non-IID problem on IoT cameras. Therefore, we open source a non-IID IoT person
detection (NIPD) data set, which is collected from five different cameras. To
our knowledge, this is the first true device-based non-IID person detection
data set. Based on this data set, we explain how to establish a FL experimental
platform and provide a benchmark for non-IID person detection. NIPD is expected
to promote the application of FL and the security of smart city.Comment: 8 pages, 5 figures, 3 tables, FL-IJCAI 23 conferenc
Emission of PAHs, NPAHs and OPAHs from residential honeycomb coal briquette combustion
Coal
combustion is one of the most significant sources of air pollution
in China. In this study, emission factors (EFs) of 15 polycyclic aromatic
hydrocarbons (PAHs), 26 nitrated PAHs (NPAHs) and 6 oxygenated PAHs
(OPAHs) were determined in five different coals with different geological
maturity (vitrinite reflectance <i>R</i><sub>O</sub> = 0.77–1.88%)
burned in the form of honeycomb briquettes. The total EFs ranged from
9.82 to 215 mg kg<sup>–1</sup> for PAHs, 0.14 to 1.88 mg kg<sup>–1</sup> for NPAHs and 4.47 to 20.8 mg kg<sup>–1</sup> for OPAHs. Measured EFs and gas-particle partitioning varied depending
on the geological maturity. The lowest EFs were found in anthracite.
The proportion of PAHs, NPAHs and OPAHs in gaseous phase increasing
with increased geological maturity. The coal with higher geological
maturity produced more 3-ring PAHs. On the basis of the statistical
analysis for the residential sector of China in 2008, PAHs, NPAHs
and OPAHs emitted from residential honeycomb coal briquettes were
4.36 Gg, 0.03 Gg and 0.47 Gg in 2007, respectively. By 2020, the emission
would decrease to 2.18 Gg, 0.02 Gg and 0.24 Gg for PAHs, NPAHs and
OPAHs due to the increasing usage of new energy resources. If only
anthracite is used as the residential coal, 93% PAHs, 87% NPAHs and
71% OPAHs would be reduced in 2020
Co-making the future: judges’ insights on transdisciplinary creativity and global collaboration in the China-U.S. young maker competition
This paper examines the future of maker education through an analysis of feedback from judges in the China-U.S. Young Maker Competition. Drawing on inputs from 36 judges from diverse backgrounds in academia, industry, and sponsoring companies, the study uses thematic analysis of interviews, feedback, and focus group discussions to uncover key educational trends. It highlights critical themes such as transdisciplinary creativity, real-world application, sustainability, cross-cultural collaboration, and innovation mindset. The research reveals a trend towards integrating various academic fields to boost creative problem-solving and application in real-life scenarios. Sustainability is identified as a crucial component, pointing to the need for environmentally aware education. The study also emphasizes the importance of cross-cultural collaboration for global interconnectedness and adaptive problem-solving, alongside fostering a continuous innovation mindset in students. Concluding with future directions for maker education, the paper advocates for an experiential, inclusive, and forward-looking educational approach. It underscores the importance of a broad curriculum that integrates entrepreneurial skills, promotes lifelong learning, and enhances global connectivity. This study provides insights for educators, policymakers, and practitioners, offering a streamlined roadmap for advancing maker education in a rapidly evolving global context
Measurement report: Molecular characteristics of cloud water in southern China and insights into aqueous-phase processes from Fourier transform ion cyclotron resonance mass spectrometry
Characterizing the molecular composition of cloud water could provide unique insights into aqueous chemistry. Field measurements were conducted at Mt. Tianjing in southern China in May, 2018. There are thousands of formulas (CHONS) identified in cloud water by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). CHON formulas (formulas containing C, H, O, and N elements; the same is true for CHO and CHOS) represent the dominant component (43.6 %–65.3 % of relative abundance), followed by CHO (13.8 %–52.1%). S-containing formulas constitute ∼5 %–20 % of all assigned formulas. Cloud water has a relative-abundance-weighted average O/C of 0.45–0.56, and the double bond equivalent of 5.10–5.70. Most of the formulas (>85 %) are assigned as aliphatic and olefinic species. No statistical difference in the oxidation state is observed between cloud water and interstitial PM. CHON with aromatic structures are abundant in cloud water, suggesting their enhanced in-cloud formation. Other organics in cloud water are mainly from biomass burning and oxidation of biogenic volatile organic compounds. The cloud water contains more abundant CHON and CHOS at night, which are primarily contributed by −NO function and organosulfates, demonstrating the enhanced formation in dark aqueous or multi-phase reactions. While more abundant CHO is observed during the daytime, likely due to the photochemical oxidation and photolysis of N- or S-containing formulas. The results provide an improved understanding of the in-cloud aqueous-phase reactions
Impact of in-cloud aqueous processes on the chemical compositions and morphology of individual atmospheric aerosols
The composition, morphology, and mixing structure of individual cloud residues (RES) and interstitial particles (INT) at a mountaintop site were investigated. Eight types of particles were identified, including sulfate-rich (S-rich), S-organic matter (OM), aged soot, aged mineral dust, aged fly ash, aged metal, refractory, and aged refractory mixture. A shift of dominant particle types from S-rich (29 %) and aged soot (27 %) in the INT to aged refractory mixture (23 %) and S-OM (22 %) in the RES is observed. In particular, particles with organic shells are enriched in the RES (27 %) relative to the INT (12 %). Our results highlight that the formation of more oxidized organic matter in the cloud contributes to the existence of organic shells after cloud processing. The fractal dimension (D), a morphologic parameter to represent the branching degree of particles, for soot particles in the RES (1.82 ± 0.12) is lower than that in the INT (2.11 ± 0.09), which indicates that in-cloud processes may result in less compact soot. This research emphasizes the role of in-cloud processes in the chemistry and microphysical properties of individual particles. Given that organic coatings may determine the particle hygroscopicity, activation ability, and heterogeneous chemical reactivity, the increase of OM-shelled particles upon in-cloud processes should have considerable implications
Shenxian-Shengmai Oral Liquid Reduces Myocardial Oxidative Stress and Protects Myocardium from Ischemia-Reperfusion Injury
Background/Aims: Shenxian-shengmai (SXSM) oral liquid, a Chinese patent compound medicine, has been used to treat sinus bradyarrhythmias induced by mild sick sinus syndrome in clinical practice. Myocardial ischemia, in particular in serious or right coronary-related heart diseases, can cause bradyarrhythmias and cardiac dysfunction. Moreover, reperfusion of ischemic myocardium is associated with additional myocardial damage known as myocardial ischemia-reperfusion (I/R) injury. This study was designed to evaluate the effects of SXSM on bradyarrhythmias and cardiac dysfunction induced by myocardial I/R injury, and to explore the underlying mechanisms. Methods: Administration of SXSM to adult male Sprague Dawley (SD) rats was achieved orally by gavage and control rats were given equivalent deionized water every day for 14 days. After the last administration, the heart was connected with the Langendorff perfusion apparatus and both groups were subjected to ischemia for 20 min followed by reperfusion for 40 min to induce myocardial I/R injury. Heart rate (HR), left ventricular developed pressure (LVDP), the maximal increase rate of left ventricular pressure (+dp/dtmax) and the maximal decrease rate of left ventricular pressure (-dp/dtmax) were recorded by a physiological signal acquisition system. The heart treated with ischemic preconditioning (IPC) for 3 times at a range of 5 min/time before ischemia served as a positive control group. The hearts without I/R injury served as control group. After reperfusion, superoxide dismutase (SOD), glutathione (GSH) and glutathione peroxidase (GSH-Px) activities in the myocardium were determined by appropriate assay kits. Myocardial SOD1 and glutamate cysteine ligase catalytic subunit (GCLC) expression were assessed by western blot analysis. For the in vitro study, SXSM serum was prepared according to the serum pharmacological method and neonatal rat cardiomyocytes were isolated from the heart of new born SD rats. Neonatal rat cardiomyocytes were pretreated with SXSM serum and subjected to H2O2 or anoxia/ reoxygenation (A/R) treatment to induce oxidative damage. Cell viability was evaluated using a Cell Counting Kit-8 (CCK8) assay. Levels of reactive oxygen species (ROS), SOD, GSH and GSH-Px in cardiomyocytes were determined by appropriate assay kits. SOD1 and GCLC expression were assessed by western blot analysis. Buthionine-[S, R]-sulfoximine (BSO), a GCLC inhibitor, and SOD1 siRNA were also used for identifying the cardiac protective targets of SXSM. Results: SXSM and ischemic preconditioning (IPC) significantly increased heart rate during myocardial reperfusion and protected cardiac function against myocardial I/R injury, including an increase in left ventricular diastolic pressure (LVDP), the maximal increase rate of left ventricular pressure (+dp/dtmax) and the maximal decrease rate of left ventricular pressure (-dp/dtmax). We also found that SXSM and IPC improved the expansion of myocardial interstitium, the structural abnormality and morphological changes of cardiomyocytes induced by I/R injury. Meanwhile, SXSM protected cardiomyocytes against the oxidative damage induced by H2O2 and A/R injury through reducing intracellular ROS levels. Moreover, SXSM increased SOD activity through enhancing SOD1 expression and increased GSH content through promoting GCLC expression as well as GSH-Px activity. BSO and SOD1 siRNA counteracted anti-arrhythmic and cardiac protective effect of SXSM, suggesting that the therapeutic targets of SXSM might be SOD1 and GCLC. Conclusion: SXSM is effective in protecting the myocardium from I/R injury, with myocardial SOD1 and GCLC being the potential therapeutic targets
Unveiling the additive-assisted oriented growth of perovskite crystallite for high performance light-emitting diodes.
Solution-processed metal halide perovskites have been recognized as one of the most promising semiconductors, with applications in light-emitting diodes (LEDs), solar cells and lasers. Various additives have been widely used in perovskite precursor solutions, aiming to improve the formed perovskite film quality through passivating defects and controlling the crystallinity. The additive's role of defect passivation has been intensively investigated, while a deep understanding of how additives influence the crystallization process of perovskites is lacking. Here, we reveal a general additive-assisted crystal formation pathway for FAPbI3 perovskite with vertical orientation, by tracking the chemical interaction in the precursor solution and crystallographic evolution during the film formation process. The resulting understanding motivates us to use a new additive with multi-functional groups, 2-(2-(2-Aminoethoxy)ethoxy)acetic acid, which can facilitate the orientated growth of perovskite and passivate defects, leading to perovskite layer with high crystallinity and low defect density and thereby record-high performance NIR perovskite LEDs (~800 nm emission peak, a peak external quantum efficiency of 22.2% with enhanced stability)
Beam test of a 180 nm CMOS Pixel Sensor for the CEPC vertex detector
The proposed Circular Electron Positron Collider (CEPC) imposes new
challenges for the vertex detector in terms of pixel size and material budget.
A Monolithic Active Pixel Sensor (MAPS) prototype called TaichuPix, based on a
column drain readout architecture, has been developed to address the need for
high spatial resolution. In order to evaluate the performance of the
TaichuPix-3 chips, a beam test was carried out at DESY II TB21 in December
2022. Meanwhile, the Data Acquisition (DAQ) for a muti-plane configuration was
tested during the beam test. This work presents the characterization of the
TaichuPix-3 chips with two different processes, including cluster size, spatial
resolution, and detection efficiency. The analysis results indicate the spatial
resolution better than 5 and the detection efficiency exceeds 99.5 %
for both TaichuPix-3 chips with the two different processes
Eucalyptus Trees - Ageratina adenophora Complex System: A New Eco-environmental Protection Model
Eucalyptus trees and Ageratina adenophora complex system, a new ecological phenomenon that is worthy of attention, was proposed firstly in this paper, and some scientific problems were summarized from the new phenomenon. Causes of the new phenomenon were analyzed tentatively from the perspective of ecology. It was pointed out that ecological degradation of Eucalyptus plantation and strong invasiveness of A. adenophora are two apparent reasons for formation of Eucalyptus trees and A. adenophora complex system. Basic view of the authors on causes of the new phenomenon was put forward that resistance unbalance between chemical defensive potential of Eucalyptus trees and chemical invasive potential of A. adenophora might be the fundamental reason for formation of Eucalyptus trees and A. adenophora complex system, based on the two apparent reasons respectively connected with allelopathic effects of Eucalyptus trees and A. adenophora as dominant species of the complex system. Some proofs from studies on chemical components and biological activities of Eucalyptus species and A. adenophora have proved the basic view of the authors. It was discussed that formation of the complex system would influence some environmental elements such as soil environment, hydrology environment, and biology environment. It was proposed that three key scientific issues, namely chemical mechanism of formation of the complex system, ecological effects of formation of the complex system, and succession trends and impact factors of the complex system should be mainly studied as special researches to probe ecological relationship of exotic species because of absence study on the complex system and objective requirements of production practice in future. It was emphasized that the proposed researches might be of guidance significance to scientific management and sustainable operation of Eucalyptus plantation under the condition of biological invasion.Eucalyptus trees and Ageratina adenophora complex system, a new ecological phenomenon that is worthy of attention, was proposed firstly in this paper, and some scientific problems were summarized from the new phenomenon. Causes of the new phenomenon were analyzed tentatively from the perspective of ecology. It was pointed out that ecological degradation of Eucalyptus plantation and strong invasiveness of A. adenophora are two apparent reasons for formation of Eucalyptus trees and A. adenophora complex system. Basic view of the authors on causes of the new phenomenon was put forward that resistance unbalance between chemical defensive potential of Eucalyptus trees and chemical invasive potential of A. adenophora might be the fundamental reason for formation of Eucalyptus trees and A. adenophora complex system, based on the two apparent reasons respectively connected with allelopathic effects of Eucalyptus trees and A. adenophora as dominant species of the complex system. Some proofs from studies on chemical components and biological activities of Eucalyptus species and A. adenophora have proved the basic view of the authors. It was discussed that formation of the complex system would influence some environmental elements such as soil environment, hydrology environment, and biology environment. It was proposed that three key scientific issues, namely chemical mechanism of formation of the complex system, ecological effects of formation of the complex system, and succession trends and impact factors of the complex system should be mainly studied as special researches to probe ecological relationship of exotic species because of absence study on the complex system and objective requirements of production practice in future. It was emphasized that the proposed researches might be of guidance significance to scientific management and sustainable operation of Eucalyptus plantation under the condition of biological invasion
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