3,103 research outputs found
Active-IRS Aided Wireless Network: System Modeling and Performance Analysis
Active intelligent reflecting surface (IRS) enables flexible signal
reflection control with \emph{power amplification}, thus effectively
compensating the product-distance path-loss in conventional passive-IRS aided
systems. In this letter, we characterize the communication performance of an
active-IRS aided single-cell wireless network. To this end, we first propose a
\emph{customized} IRS deployment strategy, where the active IRSs are uniformly
deployed within a ring concentric with the cell to serve the users far from the
base station. Next, given the Nakagami- fading channel, we characterize the
cascaded active-IRS channel by using the \emph{mixture Gamma distribution}
approximation and derive a closed-form expression for the mean signal-to-noise
ratio (SNR) at the user averaged over channel fading. Moreover, we numerically
show that to maximize the system performance, it is necessary to choose a
proper active-IRS density given a fixed number of total reflecting elements,
which significantly differs from the passive-IRS case for which the centralized
IRS deployment scheme is better. Furthermore, the active-IRS aided wireless
network achieves higher spatial throughput than the passive-IRS counterpart
when the total number of reflecting elements is small
STR-906: COMPUTER-IMAGE-BASED LOOSENED BOLT DETECTION USING SUPPORT VECTOR MACHINES
Despite many contact-sensor-based methods have been proposed to monitor and detect structural defects, there are still difficulties compensating for environmental effects and malfunctions of attached sensors, which are main reasons for transmitting false signals. Moreover, regardless of releasing correct or incorrect signals, it eventually leads to human-conducted on-site inspections. In light of these shortcomings, vision-based inspections are considered as potential approach to overcome the explained issues. A number of vision-based methods for detecting damages from images have been developed. However, there are only a few vision-based methods for detecting loosened bolts. Thus, a computer-vision method for detecting loosened bolts is proposed. This study includes two algorithms. The first one is a preprocessing to crop bolt images from bolted-joint images. The second algorithm is a feature extraction by integrating previously proposed algorithms in computer-vision. To accomplish an automated inspection, linear support vector machine is trained and used as a classifier. The robustness of the proposed is verified by the experimental validation; 22 bolt images are used to build a classifier, and 40 bolt images are tested
Effects of aiming lines and visual function on the golf putting alignment
Background: In golf, a player hits a ball with a club, aiming to transfer the ball successively into a series of hole cups in a course consisting of 18 (or fewer) holes. This study aimed to compare the impact of visual function and the presence and number of aiming lines on golf putting alignment between beginner and expert golfers.
Methods: In this prospective comparative study, 43 participants with a mean ± standard deviation (SD) of corrected distance binocular visual acuity of –0.07 ± 0.74 logarithm of the minimum angle of resolution, who knew their average golf scores, were divided into beginner and expert golfers. Six visual function tests were conducted to assess heterotropia, dominant eye, verification of current spectacles, static visual acuity, stereopsis, and fixation disparity. At the putting distances of 1.5 m and 3 m, alignment errors were measured five times each, using golf balls with 1 and 3 aiming line(s) and putters with 1 and 3 aiming line(s).
Results: The mean ± SD of age was 48.33 ± 10.07 years for study participants overall. The accuracy of ball alignment was not affected by the career or number of aiming lines, but the putter alignment was higher for the 3-lines putter than for the 1-line putter (P < 0.05). When the number and shape of the aiming line were the same for both the ball and putter, the aiming accuracy was found to be higher. In both stereopsis and fixation disparity, the combination of putting distance and a 3-lines ball showed negative values; all other combinations showed positive values, but no statistically significant correlation was detected (all P > 0.05).
Conclusions: The accuracy of golf ball alignment did not depend on the number of aiming lines and the golfer’s career. However, the predicted putting success rate and subjective satisfaction were increased when three-line golf balls and putters were used, as compared to when one-line golf balls and putters were used.
How to cite this article: Kim YJ, Jin YG, Koo BY, Jang JU, Mah KC. Effects of aiming lines and visual function on the golf putting alignment. Med Hypothesis Discov Innov Optom.2021 Spring; 2(1): 41-49. DOI: https://doi.org/10.51329/mehdioptometry12
increased Igfbp2 Levels By Placenta-Derived Mesenchymal Stem Cells Enhance Glucose Metabolism in a Taa-injured Rat Model Via ampk Signaling Pathway
The insulin resistance caused by impaired glucose metabolism induces ovarian dysfunction due to the central importance of glucose as a source of energy. However, the research on glucose metabolism in the ovaries is still lacking. The objectives of this study were to analyze the effect of PD-MSCs on glucose metabolism through IGFBP2-AMPK signaling and to investigate the correlation between glucose metabolism and ovarian function. Thioacetamide (TAA) was used to construct a rat injury model. PD-MSCs were transplanted into the tail vein (2 × 1
IDENTIFICATION OF PICK UP NOISE FOR LASER PRINTERS BASED ON PSYCHOACOUSTIC PARAMETERS
ABSTRACT This paper illustrates that a method for identification of pick up noise and an analysis the cause of pick up noise by substituting components of a laser printer. The operating sound radiated from a laser printer includes the tonal noise components caused by the rotating mechanical components such as gear, shaft, motor, fan, etc. A sound operated by laser printers has become important competitiveness in printer industries as the demand of laser printers increases. Especially, a noise between a friction pad and a paper in the process of printing has become an essential issue in an aspect of quality evaluation. However the existing criteria for determining the above noise have solely relied on human's subjective judgments; which highlights the requirement to objectify these criteria. In this paper, the standard of existing pick up noise is established by finding the tonality, which is a psychoacoustic parameter, of noticeable limit sound level. Based on the findings of the method, the study has found factors which cause pick-up noise and suggests the substitution of following components of printers such as: spring constants, spring force, and the quality of friction pads. As a result, it is confirmed that the proposed pick up noise index has usefulness to classify whether existence of pick up noise with an objective evaluation and not to occur the noise based on design optimized combination of laser printer components
Comparison of Second and Third Editions of the Bayley Scales in Children With Suspected Developmental Delay
ObjectiveTo compare the scores of the Bayley Scales of Infant Development second edition (BSID-II) and the third edition, Bayley-III, in children with suspected developmental delay and to determine the cutoff score for developmental delay in the Bayley-III.MethodsChildren younger than 42 months (n=62) with suspected developmental delay who visited our department between 2014 and 2015 were assessed with both the BSID-II and Bayley-III tests.ResultsThe mean Bayley-III Cognitive Language Composite (CLC) score was 5.8 points higher than the mean BSID-II Mental Developmental Index (MDI) score, and the mean Bayley-III Motor Composite (MC) score was 7.9 points higher than the mean BSID-II Psychomotor Developmental Index (PDI) score. In receiver operating characteristic (ROC) analysis of a BSID-II MDI score <70, Bayley-III CLC scores showed a cutoff of 78.0 (96.6% sensitivity and 93.9% specificity). In ROC analysis of a BSID-II PDI score <70, the Bayley-III MC score showed a cutoff of 80.ConclusionThere was a strong correlation between the BSID-II and Bayley-III in children with suspected developmental delay. The Bayley-III identified fewer children with developmental delay. The recommended cutoff value for developmental delay increased from a BSID-II score of 70 to a Bayley-III CLC score of 78 and Bayley-III MC score of 80
Encoder-decoder multimodal speaker change detection
The task of speaker change detection (SCD), which detects points where
speakers change in an input, is essential for several applications. Several
studies solved the SCD task using audio inputs only and have shown limited
performance. Recently, multimodal SCD (MMSCD) models, which utilise text
modality in addition to audio, have shown improved performance. In this study,
the proposed model are built upon two main proposals, a novel mechanism for
modality fusion and the adoption of a encoder-decoder architecture. Different
to previous MMSCD works that extract speaker embeddings from extremely short
audio segments, aligned to a single word, we use a speaker embedding extracted
from 1.5s. A transformer decoder layer further improves the performance of an
encoder-only MMSCD model. The proposed model achieves state-of-the-art results
among studies that report SCD performance and is also on par with recent work
that combines SCD with automatic speech recognition via human transcription.Comment: 5 pages, accepted for presentation at INTERSPEECH 202
Red pepper seed water extract inhibits preadipocyte differentiation and induces mature adipocyte apoptosis in 3T3-L1 cells
BACKGROUND/OBJECTIVES: Reducing the number of adipocytes by inducing apoptosis of mature adipocytes as well as suppressing differentiation of preadipocytes plays an important role in preventing obesity. This study examines the anti-adipogenic and pro-apoptotic effect of red pepper seed water extract (RPS) prepared at 4°C (RPS4) in 3T3-L1 cells.
MATERIALS/METHODS: Effect of RPS4 or its fractions on lipid accumulation was determined in 3T3-L1 cells using oil red O (ORO) staining. The expressions of AMP-activated protein kinase (AMPK) and adipogenic associated proteins [peroxisome proliferator-activated receptor-γ (PPAR-γ), CCAAT/enhancer-binding proteins α (C/EBP α), sterol regulatory element binding protein-1c (SREBP-1c), fatty acid synthase (FAS), and acetyl-CoA carboxylase (ACC)] were measured in 3T3-L1 cells treated with RPS4. Apoptosis and the expression of Akt and Bcl-2 family proteins [B-cell lymphoma 2 (Bcl-2), Bcl-2-associated death promoter (Bad), Bcl-2 like protein 4 (Bax), Bal-2 homologous antagonist/killer (Bak)] were measured in mature 3T3-L1 cells treated with RPS4.
RESULTS: Treatment of RPS4 (0-75 ug/mL) or its fractions (0-50 ug/mL) for 24 h did not have an apparent cytotoxicity on pre and mature 3T3-L1 cells. RPS4 significantly suppressed differentiation and cellular lipid accumulation by increasing the phosphorylation of AMPK and reducing the expression of PPAR-γ, C/EBP α, SREBP-1c, FAS, and ACC. In addition, all fractions except ethyl acetate fraction significantly suppressed cellular lipid accumulation. RPS4 induced the apoptosis of mature adipocytes by hypophosphorylating Akt, increasing the expression of the pro-apoptotic proteins, Bak, Bax, and Bad, and reducing the expression of the anti-apoptotic proteins, Bcl-2 and p-Bad.
CONCLUSIONS: These finding suggest that RPS4 can reduce the numbers as well as the size of adipocytes and might useful for preventing and treating obesity
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The Thermogenic Characteristics of Adipocytes Are Dependent on the Regulation of Iron Homeostasis
The development of thermogenic adipocytes concurs with mitochondrial biogenesis, an iron-dependent pathway. Iron regulatory proteins (IRP) 1 and 2 are RNA-binding proteins that regulate intracellular iron homeostasis. IRPs bind to the iron-response element (IRE) of their target mRNAs, balancing iron uptake and deposition at the posttranscriptional levels. However, IRP/IRE-dependent iron regulation in adipocytes is largely unknown. We hypothesized that iron demands are higher in brown/beige adipocytes than white adipocytes to maintain the thermogenic mitochondrial capacity. To test this hypothesis, we investigated the IRP/IRE regulatory system in different depots of adipose tissue. Our results revealed that 1) IRP/IRE interaction was increased in proportional to the thermogenic function of the adipose depot, 2) adipose iron content was increased in adipose tissue browning upon beta 3-adrenoceptor stimulation, while decreased in thermoneutral conditions, and 3) modulation of iron content was linked with mitochondrial biogenesis. Moreover, the iron requirement was higher in HIB1B brown adipocytes than 3T3-L1 white adipocytes during differentiation. The reduction of the labile iron pool (LIP) suppressed the differentiation of brown/beige adipocytes and mitochondrial biogenesis. Using the Fe-59-Tf, we also demonstrated that thermogenic stimuli triggered cell-autonomous iron uptake and mitochondrial compartmentalization as well as enhanced mitochondrial respiration. Collectively, our work demonstrated that IRP/IRE signaling and subsequent adaptation in iron metabolism are a critical determinant for the thermogenic function of adipocytes
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