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1.
PLoS One ; 19(3): e0300893, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38512821

RESUMO

In the artistic sports program, the referee' scores directly determine the final results of the athletes. Wushu is a artistic sport that has a Chinese characteristic and has the potential to become an official competition at the Summer Olympic. In this study we tested whether a red uniform color affects Wushu Routine practitioners' ratings of athletes' position or movement of Wushu Routine. We also tested whether the effect varied depending on the gender of the athlete and the practitioner, and depending on whether female practitioners were in the ovulation phase of their menstrual cycle. Male (Experiment 1: N = 72) and female (Experiment 1: N = 72; Experiment 2: N = 52) participants who major in Wushu Routine were recruited to take a referee's perspective and rate the movement quality of male and female athletes wearing red or blue uniforms. The results of Experiment 1 showed that both male and female athletes wearing red uniform (compared to blue uniform) received higher ratings (p = .002, η2 = .066; p = .014, η2 = .043), and the red effect was especially strong when male practitioners rated female athletes (p = .002, η2 = .069). The results of Experiment 2, in an all-female sample, showed that in most cases there was no difference in ratings made by women in the ovulation and non-ovulation phases of their menstrual cycle, with the exception of their ratings of male athletes wearing red; in this condition, women gave higher ratings when they were in the ovulation phase of their cycle (p = .026). The results suggest that there is a red effect in an artistic sport like Wushu Routine, in which gender and the female menstrual cycle play an important role.


Assuntos
Julgamento , Artes Marciais , Humanos , Masculino , Feminino , Atletas , Ciclo Menstrual , Ovulação
2.
Acta Psychol (Amst) ; 243: 104171, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38320412

RESUMO

Color is not just about aesthetics but also communicates specific information and has important implications for psychological functioning. It has been shown that the color red enhances perceived attractiveness when evaluating the opposite sex, which we call the red-attractiveness effect. However, few studies have attached importance to the social context in which attractiveness ratings are made, which means that the red-attractiveness effect is rarely explained by analyzing the role of social context. We conducted two experiments to test the red-attractiveness effect in Chinese culture and the influence of context (affiliation or competitive) on the red-attractiveness effect. Experiment 1 (160 Chinese college students, 80 males) showed that the opposite-sex target in red, compared to white, was rated more attractive, and the red-attractiveness effect was applicable to Chinese culture. Experiment 2 (480 Chinese college students, 240 males) found that perceived attractiveness was strengthened in the affiliation context and weakened in the competitive context, that is, the main effect of context was significant. We did not find any significant effect of the color red in either context, that is, the color main effect was not significant. However, the results indicate that red can enhance perceived attractiveness when evaluating the opposite sex. This study demonstrates that the red attractiveness effect may exist in different cultural backgrounds and contexts.


Assuntos
Estética , Comportamento Sexual , Humanos , Masculino , Comportamento Sexual/psicologia , Estudantes/psicologia , População do Leste Asiático , Feminino , Cor
3.
Opt Express ; 31(24): 40705-40716, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38041363

RESUMO

A novel diversity combining scheme, in conjunction with the complex-valued decision-directed least mean square (CV-DD-LMS) algorithm, is evaluated, and a real-time experimental validation is presented. This proposed scheme employs the CV-DD-LMS algorithm to concurrently perform beam combination and carrier phase recovery (CPR), thereby effectively reducing the overall complexity of digital signal processing. Furthermore, in the numerical simulation, under a low signal-to-noise ratio (SNR), a scheme utilizing the CV-DD-LMS algorithm effectively avoids cycle slips (CS) and outperforms schemes employing independent CPR modules. We experimentally validate this novel scheme by implementing it on an FPGA in a real-time 2.5Gb/s QPSK diversity-receiving system with three inputs. The back-to-back sensitivity is assessed using static received optical power, while the dynamic performance is evaluated by employing variable optical attenuators (VOAs) to simulate a power fluctuation at a frequency of 100kHz. The result proves that the implementation of the CV-DD-LMS algorithm yields stable performance while effectively reducing computational complexity.

4.
Opt Express ; 31(23): 39307-39322, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-38018012

RESUMO

Point cloud registration based on local descriptors plays a crucial role in 3D computer vision applications. However, existing methods often suffer from limitations such as low accuracy, a large memory footprint, and slow speed, particularly when dealing with 3D point clouds from low-cost sensors. To overcome these challenges, we propose an efficient local descriptor called Binary Weighted Projection-point Height (BWPH) for point cloud registration. The core idea behind the BWPH descriptor is the integration of Gaussian kernel density estimation with weighted height characteristics and binarization components to encode distinctive information for the local surface. Through extensive experiments and rigorous comparisons with state-of-the-art methods, we demonstrate that the BWPH descriptor achieves high matching accuracy, strong compactness, and feasibility across contexts. Moreover, the proposed BWPH-based point cloud registration successfully registers real datasets acquired by low-cost sensors with small errors, enabling accurate initial alignment positions.

5.
Opt Express ; 31(20): 33704-33718, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37859144

RESUMO

The Segmented Planar Imaging Detector for Electro-Optical Reconnaissance (SPIDER) is a small volume, lightweight, low energy consumption, and high-resolution system expected to replace traditional large aperture telescopes for long-distance detection. In this paper, an improved SPIDER system is proposed, which uses a multimode interference (MMI) coupler instead of an orthogonal detector, and successfully doubles the space spectrum coverage. We present a three-point configuring method to configure lenslets, calculate spatial spectrum values from the output currents obtained by MMI. By comparing the performance of the MMI-SPIDER and SPIDER systems through simulations, we demonstrate that the former has more complete spatial spectrum coverage, resulting in better image restoration quality.

6.
Opt Lett ; 48(19): 5169-5172, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37773412

RESUMO

The impacts of limited bandwidth on the nonlinear transmission performance are investigated by employing a truncated probabilistic shaped 64-ary quadrature amplitude modulation (TPS-64QAM) and a uniformly distributed 16-ary quadrature amplitude modulation (UD-16QAM) over a bandwidth-limited 75-GHz spaced 25-Tb/s (60 × 416.7 Gb/s) 6300-km transmission system. In terms of nonlinear performance measured by optimal launch power, theoretical analyses show that a 0.4-dB improvement could be introduced by UD-16QAM with respect to TPS-64QAM over a 6300-km transmission without limited bandwidth. However, contrary results would be observed that TPS-64QAM would outperform UD-16QAM by about 0.8 dB in terms of optimal launch power when the impacts of limited bandwidth are considered. Besides, numerical simulations and experimental results could both validate that about 1.0-dB optimal launch power improvement could be obtained by TPS-64QAM under bandwidth-limited cases, which is roughly similar to the results of theoretical analyses. Additionally, WDM experimental results show that all 60 tested channels could agree with the BER requirements by employing TPS-64QAM, further validating the superiority of TPS-64QAM compared to UD-16QAM under bandwidth-limited cases.

7.
Sensors (Basel) ; 23(14)2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37514622

RESUMO

Three-dimensional LiDAR systems that capture point cloud data enable the simultaneous acquisition of spatial geometry and multi-wavelength intensity information, thereby paving the way for three-dimensional point cloud recognition and processing. However, due to the irregular distribution, low resolution of point clouds, and limited spatial recognition accuracy in complex environments, inherent errors occur in classifying and segmenting the acquired target information. Conversely, two-dimensional visible light images provide real-color information, enabling the distinction of object contours and fine details, thus yielding clear, high-resolution images when desired. The integration of two-dimensional information with point clouds offers complementary advantages. In this paper, we present the incorporation of two-dimensional information to form a multi-modal representation. From this, we extract local features to establish three-dimensional geometric relationships and two-dimensional color relationships. We introduce a novel network model, termed MInet (Multi-Information net), which effectively captures features relating to both two-dimensional color and three-dimensional pose information. This enhanced network model improves feature saliency, thereby facilitating superior segmentation and recognition tasks. We evaluate our MInet architecture using the ShapeNet and ThreeDMatch datasets for point cloud segmentation, and the Stanford dataset for object recognition. The robust results, coupled with quantitative and qualitative experiments, demonstrate the superior performance of our proposed method in point cloud segmentation and object recognition tasks.

8.
Ultrasonics ; 132: 107019, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37105020

RESUMO

Damage imaging technology based on ultrasonic guided wave can characterize and visualize structural damage. However, current imaging methods require high accuracy in wave packets information extraction, resulting in artifacts, large spots and false imaging. Therefore, an intelligent colony optimization imaging method is proposed to transform the damage imaging problem into the scattering sources search problem. The number of imaging trajectories through potential scattering sources is employed as the fitness function to assess the damage possibility in this individual. The fitness function is further implemented to particle swarm optimization algorithm for iterative search of actual scattering sources to find out the damage area with highest damage possibility. After the scattering sources search, the location of the damage can be identified through observing the distribution of the population. The experimental results illustrate that the proposed intelligent imaging method can accurately locate the crack damage of different lengths and delamination damage in composites, and the damage imaging effect is better than that of elliptic imaging.

9.
Opt Express ; 30(15): 26774-26786, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-36236863

RESUMO

We demonstrate a real-time coherent optical receiver based on a single field programmable gate array (FPGA) chip. To strike the balance between the performance and hardware resources, we use a clock recovery scheme using the optimal interpolation (OI). The performance and complexity of the OI-based scheme and the traditional schemes are compared and discussed via offline digital signal processing. And a real-time 15GBaud single-polarization 16QAM transmission experiment under different received optical power using the FPGA-based receiver is carried out to demonstrate the overall performance of different clock recovery and equalization schemes. The result proves that, compared to the traditional scheme with a cubic interpolator and a 7-tap equalizer, the optimal interpolator significantly lowers the utilization of LUT, CARRY8, and DSP48 by 35%, 50%, and 11%, respectively, and can work properly under a received optical power of -40dBm.

10.
Front Psychol ; 13: 894694, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36275229

RESUMO

The psycho-lexical approach can be effectively used to explore the structure of sports culture. Based on a lexical list of adjective vocabulary reflecting sports culture and through an item analysis, 87 discriminating objectives were selected representing sports culture. Objective: To explore the structure of sports culture from the objectives lexicons. Methods: Item analysis and factor analysis were adopted to abstract the structure of sports culture. Results: Through a principal component analysis, a structure of six factors including extroversion-activity, diligence-progression, experience, independence-excellence, enjoyment, and body culture was extracted. Through a second-order factor analysis, a psychological structure of sports culture consisting of six dimensions and 12 factors was extracted, and result of the reliability analysis revealed good Cronbach α coefficient and test-retest reliability coefficient. Conclusion: The psycho-lexical structure of sports culture can be used to understand structure of sports culture.

11.
Appl Opt ; 61(29): 8792-8798, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36256013

RESUMO

The feedback loop in dual Mach-Zehnder interferometer (DMZI) sensors stabilizes the system operating at the quadratic point for the highest sensitivity but requires the minimum measurable vibration frequency out of the feedback bandwidth, resulting in a limited dynamic range. In this paper, we point out that the feedback operation is unnecessary while vibration is occurring and propose a strategy to adaptively enable/disable the feedback phase compensation depending on the vibration state, lowering the minimum measurable vibration frequency tenfold. Moreover, the state variable employed enables direct extraction of vibration-related data, with no need of complicated postprocessing algorithms.

12.
Educ Technol Res Dev ; 70(6): 2235-2254, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35789970

RESUMO

The outbreak and continuation of the COVID-19 pandemic has challenged the implementation of physical education theory (PET) curriculums among global colleges and universities. This study aimed to describe the design and students' evaluation of a blended "Sports Multimedia Courseware Design" course among Chinese university students during the COVID-19 pandemic. Using information communication technologies, a 4-month blended course was developed, which consisted of 36 credits (18-credit online self-learning + 18-credit offline group-learning). A total of 1300 Chinese university students who majored in physical education, completed the blended course from Mar to Jun 2020, among which 238 (69.75% males; 21 ± 1.2 years) were randomly recruited to evaluate the course in terms of three aspects: (1) online self-learning, (2) offline group-learning, and (3) overall learning outcomes. A descriptive analysis was conducted using the IBM SPSS 27.0. Students' overall positive evaluation supported a successful development and implementation of the blended course. Over 90% of students fulfilled the learning tasks and satisfied with the online learning resources. About 83% of students indicated high levels of autonomous motivation and engagement in online self-learning. Approximately 88% of students showed positive attitudes to the offline group-learning content, while the participation rate (60%) was relatively lower than of the online self-learning. Over 50% of the students indicated self-improvements in diverse aspects after attending the blended course. Blended online and offline pedagogy shows apparent promise in delivering the PET course among Chinese university students during the COVID-19 pandemic. Further application and comprehensive evaluation are warranted in the future.

13.
Artigo em Inglês | MEDLINE | ID: mdl-35742324

RESUMO

Prior research has found the differential strength of optimism and pessimism in predicting physical health. However, whether similar findings would be obtained in predicting subjective well-being and the possible underlying mechanisms are still unclear. This study examined the relative strength of optimism and pessimism in predicting adolescent life satisfaction and depression, and further explored the possible mediating mechanisms from the perspective of emotion regulation. A sample of 2672 adolescents (Mage = 13.54 years, SD = 1.04; 55.60% boys) completed a survey assessing optimism and pessimism, the habitual use of reappraisal and acceptance strategies, life satisfaction, and depression. The results from dominance analysis revealed that the presence of optimism was more powerful than the absence of pessimism in predicting adolescent life satisfaction, while the absence of pessimism was more powerful than the presence of optimism in predicting adolescent depression. Moreover, mediation models showed that reappraisal and acceptance mediated both the link between optimism and life satisfaction and the link between pessimism and depression. These findings suggest possible avenues for intervening in different aspects of adolescent subjective well-being.


Assuntos
Pessimismo , Adolescente , Feminino , Humanos , Masculino , Otimismo/psicologia , Pessimismo/psicologia , Inquéritos e Questionários
14.
Opt Express ; 30(9): 14421-14431, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35473185

RESUMO

In this paper, for the first time, a probability-aided maximum-likelihood sequence detector (PMLSD) is experimentally investigated through a 64-GBaud probabilistic shaped 16-ary quadrature amplitude modulation (PS-16QAM) transmission experiment. In order to relax the impacts of PS technology on the decision module, a PMLSD decision scheme is investigated by modifying the decision criterion of maximum-likelihood sequence detector (MLSD) correctly. Meanwhile, a symbol-wise probability-aided maximum a posteriori probability (PMAP) scheme is also demonstrated for comparison. The results show that the PMLSD scheme outperforms the direct decision scheme about 1.0-dB optical signal to noise ratio (OSNR) sensitivity. Compared with symbol-wise PMAP scheme, PMLSD scheme can effectively relax the impacts of PS technology on the decision module and a more than 0.8-dB improvement in terms of OSNR sensitivity in back-to-back (B2B) case is obtained. Finally, we successfully transmit the PS-16QAM signals over a 2400-km fiber link with a bit error ratio (BER) lower than 1.00×10-3 by adopting the PMLSD scheme.

15.
ACS Omega ; 7(4): 3713-3721, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35128279

RESUMO

Machine learning and deep learning have facilitated various successful studies of molecular property predictions. The rapid development of natural language processing and graph neural network (GNN) further pushed the state-of-the-art prediction performance of molecular property to a new level. A geometric graph could describe a molecular structure with atoms as the nodes and bonds as the edges. Therefore, a graph neural network may be trained to better represent a molecular structure. The existing GNNs assumed homogeneous types of atoms and bonds, which may miss important information between different types of atoms or bonds. This study represented a molecule using a heterogeneous graph neural network (MolHGT), in which there were different types of nodes and different types of edges. A transformer reading function of virtual nodes was proposed to aggregate all the nodes, and a molecule graph may be represented from the hidden states of the virtual nodes. This proof-of-principle study demonstrated that the proposed MolHGT network improved the existing studies of molecular property predictions. The source code and the training/validation/test splitting details are available at https://github.com/zhangruochi/Mol-HGT.

16.
Ultrasonics ; 121: 106685, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35032840

RESUMO

Copper pipeline is a commonly used industrial transmission pipeline. Nondestructive testing of copper pipeline early damage is very important. Laser scanning has attracted extensive attention because it can realize the visualization of guided wave propagation and non-contact on-line detection. However, the damage points detection in laser scanning imaging method rely on the difference between the damage points signals and surrounding normal points signals. This limits the applicability of laser scanning and may lead to inaccurate in large-area detection. Facing with such challenges, a damage detection method based on CNN-LSTM network is proposed for laser ultrasonic guided wave scanning detection in this paper, which can detect each scanning point signal without relying on the surrounding detection points signals. Firstly, the proposed data conversion algorithm is used to preprocess the laser scanning signals. Next, CNN-LSTM network is used to train the damage detection model. Four 1D Conv channels with different convolution kernel sizes and depths are designed in Convolutional Neural Network (CNN) module. The module can extract the signal time domain features. Then the features are input into the Long Short-Term Memory Network (LSTM) for feature extraction and classification. Finally, the CNN-LSTM is trained using the laser scanning detection data collected on the copper pipeline with crack and corrosion damages, and applied to detect the copper pipeline damage signal. At the same time, the state-of-the-art methods is compared with proposed method. The experimental results show that the detection accuracy of the method is 99.9%, 99.9%, 99.8% and 99.8% for copper pipeline 0.5 mm deep crack damage, penetrating crack damage, corrosion damage and inside crack damage, respectively. The damage location and size can be accurately detected by the proposed method.

17.
Opt Express ; 29(23): 38796-38810, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34808924

RESUMO

The Hilbert transform links the log-magnitude and the phase of the field modulated signals as long as the minimum phase condition is satisfied in the Kramer-Kronig (KK) receiver. In discrete-time signal processing, the Hilbert transform is generally replaced by a finite impulse response (FIR) filter to reduce the computational complexity, that is the so-called Hilbert transform FIR (HT-FIR) filter. The performance of the HT-FIR filter is extremely important, as the in-band flatness, the ripple, the group delay, the Gibbs phenomenon, and the edge effect, which indeed impair the phase retrieval. Hence, we investigate four different HT-FIR filter schemes that are in the form of type III and type IV based on the frequency-domain (FD) sampling approach and the time-domain (TD) windowing function approach. Also, we analyze the performance for each filter under different digital upsampling scenarios and conclude that a trade-off between the reduced inter-symbol-interference (ISI) and the Gibbs phenomenon is essential to obtain an optimal sampling rate and an improved KK performance when the HT-FIR filter with a short length is adopted. The results show that the FD-based HT-FIR filter can relax the upsampling requirement while having a better in-band flatness and a lower edge effect. The experiment is conducted in the parallelized block-wise KK reception-based 112-Gbit/s SSB 16-QAM optical transmission system over a 1920-km cascaded Raman fiber amplifier (RFA) link to investigate the limit transmission performance of the practical KK receiver. The experimental results show that when the transmission distance is up to 1440-km, the BER of the FD-based HT-FIR filter can be lower than the soft decision-forward error correction (SD-FEC) threshold of 2 × 10-2 with only 3 samples per symbol (3-SPS) upsampling rate and 8 non-integer tap coefficients are used, while other TD-based HT-FIR filter schemes with a BER lower than the SD-FEC threshold require at least 4-SPS upsampling rate.

18.
Polymers (Basel) ; 13(18)2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34578020

RESUMO

Waste paper is often underutilized as a low-value recyclable resource and can be a potential source of cellulose nanofibers (CNFs) due to its rich cellulose content. Three different processes, low acid treatment, alkali treatment and bleaching treatment, were used to pretreat the waste paper in order to investigate the effect of different pretreatments on the prepared CNFs, and CNFs obtained from bleached pulp boards were used as control. All sample fibers were successfully prepared into CNFs by 2,2,6,6-tetramethyl-piperidine-1-oxyl (TEMPO) oxidation. It was quite obvious that the bleached CNFs samples showed dense fibrous structures on a scanning electron microscopy (SEM), while needle-like fibers with width less than 20 nm were observed on a transmission electron microscopy (TEM). Meanwhile, the bleaching treatment resulted in a 13.5% increase in crystallinity and a higher TEMPO yield (e.g., BCNF, 60.88%), but a decrease in thermal stability. All pretreated CNFs samples showed narrow particle size distribution, good dispersion stability (zeta potential less than -29.58 mV), good light transmission (higher than 86.5%) and low haze parameters (lower than 3.92%). This provides a good process option and pathway for scalable production of CNFs from waste papers.

19.
Opt Express ; 29(14): 22146-22158, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34265986

RESUMO

Noise models for both single-pulse and coded Brillouin optical time-domain analyzers (BOTDA) are established to quantify the actual signal-to-noise ratio (SNR) enhancement provided by pulse coding at any fiber position and in any operating condition. Simulation and experimental results show that the polarization noise and spontaneous Brillouin scattering (SpBS) to signal beating noise could highly penalize the performance of coded-BOTDA, depending on the code type and the interrogated fiber position. The models also serve as a useful tool to optimize the SNR improvement by trading off the accumulated Brillouin gain and optical noises.

20.
Opt Express ; 29(7): 10209-10220, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33820162

RESUMO

In this paper, a polar coded probabilistic shaping (PS) 8-ary pulse amplitude modulation (PAM8) based on many-to-one (MTO) mapping is investigated for short-reach optical interconnection. By ingeniously assigning parity bits to ambiguities positions, no extra PS redundancy and no complex distribution matcher are required in the scheme comparing to traditional probabilistic amplitude shaping (PAS). The noise distributions after different transmission distances are studied and an optimal clock recovery method for PS signal is proposed to degrade the impact of severe eye skew effect on BER performance. The experimental results show that up to 1.2 dB and 0.8 dB shaping gains are respectively achieved over back-to-back (BTB) and 2-km standard single mode fiber (SSMF) transmission. With the help of the proposed optimal clock recovery method in the PS scheme, the shaping gain is improved from 0.15 dB to 0.4 dB after 10-km transmission. Moreover, compared to low-density parity-check (LDPC) code, the polar coded PS-PAM8 can provide an additional coding gain of 2.2 dB with code length of 256, which proves the performance superiority of polar code in short code length. Therefore, the proposed polar coded PS-PAM8 with low complexity and satisfactory BER performance is believed to be an alternative solution for the cost-sensitive short-reach optical interconnection.

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