Scaling Coefficients Research Articles

Impact Analysis of Worn Surface Morphology on Adaptive Friction Characteristics of the Slipper Pair in Hydraulic Pump

The hydrostatic bearing slipper pair of the hydraulic pump has a unique adaptive friction characteristic, which has a better friction reduction and anti-wear ability than the general sliding friction pair, and also has a certain recovery effect on the performance degradation caused by the early wear of the slipper. This paper attempts to reveal the friction adaptive mechanism. Based on the fractal theory, two fractal parameters of fractal dimension and scale coefficient are used to characterize the surface morphology of the slipper mathematically, and the adaptive friction mechanism model is established by combining the friction coefficient equation. The effects of different fractal parameters on the friction coefficient and other performance parameters of slipper pairs are obtained by means of the numerical analysis method. The wear test was carried out by replacing specimens at different intervals to observe the worn surface morphology and the degradation process of the slipper to verify the correctness of the theoretical results. The results show that the friction performance and load-bearing capabilities of the slipper can be recovered to a certain extent within a short period when early wear occurs, and its surface performance shows the variation characteristics of deterioration-repair-re-deterioration-re-repair.

TOC prediction and grading evaluation based on variable coefficient △logR method and its application for unconventional exploration targets in Songliao Basin

The prediction of total organic carbon (TOC) content and grading evaluation of shale formation are very much significant and essential for reservoir description of rolling exploration and development in the new shale exploration area (Shuangcheng) in Songliao basin, China. In order to improve exploration efficiency and obtain continuous TOC content curve of wells, the variable coefficient △logR technique was developed for TOC estimating which is based on the two of acoustic time difference and deep lateral resistivity logging curve and the variable scale coefficient (K) between them as well as another scale coefficient (A) between TOC and △logR. A prediction model of TOC was established for the well which TOC is measured by evaluation of side wall cores, then apply it to other wells to verify the reliability of the model. The application result of eleven exploration Wells in Shuangcheng area show that the TOC of shale is linearly correlated with △logR, and the maximum prediction accuracy k value varies with wells, so it is necessary to determine the undetermined coefficient k according to a single well, but the A value having no big change from one well to another in similar sedimentary facies and thermal evolution degree of shale. The average relative error of TOC between prediction model and core measurement is 10.6% which verifies the accuracy of this method. On this basis of TOC prediction, we establish shale grading evaluation criteria for the study area. In the establishment process, not only the relationship between TOC and S1, but also vitrinite reflectance (Ro) are considered. The shale in Shuangcheng area can be divided into three types (Class I: TOC > 3.5% and Ro > 0.9%; Class II: TOC 2%–3.5% and Ro > 0.9; Class III: TOC < 2% or Ro < 0.9%), and achieved shale classification on the well profile with TOC and Ro which are easy to predict and reliable. According to the relationship between the thickness of shale of disparate classes and the total thickness of shale in different zones, the thickness of shale of disparate classes in each well is predicted.

Dose length product to effective dose coefficients in children

BackgroundThe most accurate method for estimating effective dose (the most widely understood metric for tracking patient radiation exposure) from computed tomography (CT) requires time-intensive Monte Carlo simulation. A simpler method multiplies a scalar coefficient by the widely available scanner-reported dose length product (DLP) to estimate effective dose.ObjectiveDevelop pediatric effective dose coefficients and assess their agreement with Monte Carlo simulation.Materials and methodsMulticenter, population-based sample of 128,397 pediatric diagnostic CT scans prospectively assembled in 2015–2020 from the University of California San Francisco International CT Dose Registry and the University of Florida library of highly realistic hybrid computational phantoms. We generated effective dose coefficients for seven body regions, stratified by patient age, diameter, and scanner manufacturer. We applied the new coefficients to DLPs to calculate effective doses and assessed their correlations with Monte Carlo radiation transport-generated effective doses.ResultsThe reported effective dose coefficients, generally higher than previous studies, varied by body region and decreased in magnitude with increasing age. Coefficients were approximately 4 to 13-fold higher (across body regions) for patients <1 year old compared with patients 15–21 years old. For example, head CT (54% of scans) dose coefficients decreased from 0.039 to 0.003 mSv/mGy-cm in patients <1 year old vs. 15–21 years old. There were minimal differences by manufacturer. Using age-based conversion coefficients to estimate effective dose produced moderate to strong correlations with Monte Carlo results (Pearson correlations 0.52–0.80 across body regions).ConclusionsNew pediatric effective dose coefficients update existing literature and can be used to easily estimate effective dose using scanner-reported DLP.

Pattern and effect of economic agglomeration in the Yangtze River Delta region based on population-land allometric growth

The speed of urban growth affects urban development’s momentum and urban agglomeration’s spatial state. The influence of the asymmetric flow of population and land factors on the economic agglomeration effect is an essential issue in the coordinated development of urbanization. To study its impact on the orderly development of China’s urban economy, this paper selects 41 cities in the Yangtze River Delta (YRD) region, measuring the spatial and temporal evolution of the allometric growth relationship between population and land, explores the mechanism of the effect of allometric relationships on the economic agglomeration effect. The results show that: 1) Population-land allometric growth is characterized by a transition from population to land expansion. The transition phase is divided into six stages, from positive to negative allometric growth. In terms of scaling coefficients, the period from 2000 to 2011 is characterized by negative allometric growth, and the period from 2012 to 2019 is characterized by positive allometric growth. Spatially, the Shanghai metropolitan area evolves into a positive allometric primary stage, while the core and central areas evolve into a positive allometric secondary stage, with the latter’s development transition lagging behind the former by about 10 years. 2) The spatial dependence of economic agglomeration in the Yangtze River Delta is strong, showing a spatial distribution trend of “high in the middle, low in the north and south, high in the east and low in the west,” the agglomeration gap is gradually reduced, forming a “continuous area of high-value economic agglomeration” with the core area as the center and spreading outward, reflecting the efficacy of the Yangtze River Delta integrated development strategy. 3) The economic agglomeration effect of allometric growth is classified into four types: positive-allometric positive-effect, positive-allometric negative-effect, negative-allometric positive-effect, and negative-allometric negative-effect. In the Yangtze River Delta region, 70.7% of the cities have positive effects, of which 93.1% are positive-positive. 4) The allometric growth has an important impact on the reconfiguration of economic agglomeration pattern, 78% of the cities in the study period produced leapfrog movements in different quadrants, and the incongruity between population growth and land expansion should be actively regulated in the future to promote the evolution of cities towards an intensive type of population-land coordination to lead the high-quality development of the regional economy.

Electrostatic effect due to patch potentials between closely spaced surfaces

The spatial variation and temporal variation in surface potential are important error sources in various precision experiments and deserved to be considered carefully. In the former case, the theoretical analysis shows that this effect depends on the surface potentials through their spatial autocorrelation functions. By making some modification to the quasilocal correlation model, we obtain a rigorous formula for the patch force, where the magnitude is proportional to $\frac{1}{{a}^{2}}{(\frac{a}{w})}^{\ensuremath{\beta}(a/w)+2}$ with $a$ the distance between two parallel plates, $w$ the mean patch size, and $\ensuremath{\beta}$ the scaling coefficient from $\ensuremath{-}2$ to $\ensuremath{-}4$. A torsion balance experiment is then conducted, and we obtain a 0.4 mm effective patch size and 20 mV potential variance. In the latter case, we apply an adatom diffusion model to describe this mechanism and predicts a ${f}^{\ensuremath{-}3/4}$ frequency dependence above 0.01 mHz. This prediction meets well with a typical experimental results. Finally, we apply these models to analyze the patch effect for two typical experiments. Our analysis will help to investigate the properties of surface potentials.

Cross-cultural adaptation and validation of a Spanish version of the self-administered foot evaluation questionnaire (SAFE-Q)

BackgroundThe self-administered foot evaluation questionnaire is a comprehensive measure for assessing the perception of patients regarding their foot-related problems. However, it is currently only available in English and Japanesse. Therefore, this study aimed to cross-culturally adapt the questionnaire to Spanish and assess its psychometric properties. MethodsThe methodology recommended by the International Society for Pharmaco Economics and Outcomes Research for translating and validating patient-reported outcome measures was followed for the Spanish translation. After a pilot study with 10 patients and 10 controls, an observational study was carried out between March and December 2021. The Spanish version of the questionnaire was filled by 100 patients with unilateral foot disorders, and the time spent to complete each questionnaire was recorded. Cronbach's alpha was calculated to analyze the internal consistency of the scale and Pearson's correlation coefficients for the degree of inter-subscale associations. ResultsThe maximum correlation coefficient for the Physical Functioning, Daily Living, and Social Functioning subscales was 0.768. The inter-subscale correlation coefficients were significant (p < 0.001). Additionally, the value of Cronbach's alpha for the whole scale was 0.894 (95% confidence interval, 0.858–0.924). The values of Cronbach's alpha varied between 0.863 and 0.889 when the value of one of the five subscales was suppressed, which can be considered a measure of good internal consistency. ConclusionThe Spanish version of the questionnaire is valid and reliable. The method followed for its transcultural adaptation ensured its conceptual equivalence with the original questionnaire. Health practitioners can use the self-administered foot evaluation questionnaire as a complementary method to assess the interventions performed for ankle and foot disorders among native Spanish speakers; however, further research is necessary to assess its consistency for use by populations from other Spanish-speaking countries.

Wear Model of a Mechanical Seal Based on Piecewise Fractal Theory

In this research, a model is proposed using piecewise fractal theory that considers abrasive and adhesive wear. The model demonstrated improved wear computation accuracy of a contact mechanical seal end face. The validity of the model was established by comparing the simulation results with experimental data and the conventional MB and Archard models. The loading effect and surface morphology parameters involved in wear were also investigated. Results show that severe wear occurs with increasing load ratio, large fractal dimensions, and a higher scale coefficient of the surface morphology. The findings offer a novel method for precisely calculating and projecting the amount of wear of a contact mechanical seal and predicting its wear behavior.

The Compilation of College Students’ Mental Huagong Scale Based on Chinese Culture

Chinese culture contains rich positive thoughts of mental transformation, mentcal Huagong(MHG: 心理化功) is the embodiment of people’s quality of psychological transformation. MHG refers to the Gongfu(功夫) or mental competence that transforms negative or passive into positive or advantageous mind, which is an indispensable quality for contemporary people, especially college students, to find favorable position for the use of their abilities(用武之地) in society. In order to understand the level of college students’ MHG, 586 college students from ordinary universities in Guangdong Province were tested. By item analysis and exploratory factor analysis on sample 1, confirmatory factor analysis on sample 2, college students’ mental Huagong scale(CSMHGS: 大学生心理化功量表) was compiled finally. The result shows that CSMHGS is composed of 35 items and 5 factors, and the cumulative variance contribution rate is 56.145%. The result of confirmatory factor analysis shows that the 5-factor model fitted well. Cronbach α coefficient of the total scale is 0.854, and the reliability coefficient of each dimension of the scale is between 0.809~0.856. It is concluded that CSMHGS has good reliability and validity, and can be used as a measuring tool for the study of college students’ MHG.

Development and Validation of a Distress Measurement Related to Glucose Monitoring of Diabetes Patients.

Glucose monitoring-related problems affect the social and psychological distress experienced by patients with diabetes, and this distress leads to low compliance. Consequently, it is important to be able to comprehensively assess distress due to glucose monitoring in these patients. We have developed and validated a distress of self-glucose monitoring (DSGM) scale instrument to assess patient distress from glucose monitoring. Following an extensive literature review and qualitative study, we selected 21 items for assessing the DSGM, including physical, psychosocial, and process domains. We conducted a cross-sectional study in patients with insulin-treated diabetes aged 10-40years at Samsung Medical Center, Seoul, Korea, from April 2021 to September 2021. Exploratory and confirmatory factor analyses (CFA) were performed to confirm the structural validity of the DSGM scale. To confirm construct and criterion validity, we assumed that the Korean version of the Problem Areas in Diabetes (PAID-K) instrument, life interference, and stress due to glucose monitoring might moderately correlate with the total score and scores of all domains of the DSGM scale except for the physical domain. Cronbach's alpha coefficients for the DSGM scale were 0.92, and Cronbach's alpha coefficients of the three subscales ranged from 0.69 to 0.92, indicating satisfactory internal consistency. The DSGM scale was evaluated using CFA, and the fit indices for this model were good. The PAID-K total score, life interference, and stress due to glucose monitoring were moderately correlated with the total score of the DSGM scale and with the scores of the psychosocial and process domains, and were weakly correlated with the score of the physical domain of the DSGM scale. The DSGM scale is a valid and reliable tool to evaluate distress due to glucose monitoring in adults, adolescents, and children with diabetes.

Probabilistic approach to the stability analysis of caisson foundations under combined loading in spatially variable soil

Caisson foundations are increasingly used in offshore engineering and are usually subjected to combined vertical-horizontal-moment (VHM) loading caused by self-weight, wind, waves, and currents. The bearing capacities of foundations under combined loading are represented by the VHM failure envelopes. In the literatures, failure envelopes for caisson foundations were usually established using a deterministic model of soil properties, ignoring the actual uncertainty and spatial variability of marine soil. The present study focuses on the investigation of the bearing capacities for caissons in spatially variable undrained soil under both uniaxial loading and VHM combined loading. Random finite element method combined with Kriging metamodeling technique and Monte Carlo simulation was applied to evaluate the uniaxial bearing capacities and to define the probabilistic VHM failure envelopes. The soil's undrained shear strength was considered to be increasing with depth, while its coefficient of variation was depth-independent. The effects of the coefficient of variation and scale of fluctuation of undrained shear strength on the uniaxial bearing capacity, on both size and shape of VHM failure envelopes for caisson foundations were discussed. It is shown that spatial variability of soil not only causes a change in the size of the failure envelope but also affects its shape when compared with the deterministic case. Therefore, it is necessary to consider the spatial variability of soil when designing caisson foundations and the present results provide some guidance for the design.

Sound Recognition Method of Coal Mine Gas and Coal Dust Explosion Based on GoogLeNet.

To solve the problems of backward means of coal mine gas and coal dust explosion monitoring, late reporting, and low leakage rate, a sound recognition method of coal mine gas and coal dust explosion based on GoogLeNet was proposed. After installing mining pickups in key monitoring areas of coal mines to collect the sounds of the working equipment and the environment, the collected sound was analyzed by continuous wavelet to obtain its scale coefficient map. This was then imported into GoogLeNet to obtain the recognition model of coal mine gas and coal dust explosions. The test sound was obtained by continuous wavelet analysis to obtain the scale coefficient map, brought into the completed training recognition model to obtain the sound signal class, and verified by experiment. Firstly, the scale coefficient map extracted from the sound signal by continuous wavelet analysis showed that the similarity between the subjective and objective indicators of the wavelet coefficient maps of the gas explosion sound and coal dust explosion sound was higher, but the difference between these and the rest of the coal mine sounds was clearer, helping to effectively distinguish gas and coal dust explosion sounds from other sounds. Secondly, the experimental results of GoogLeNet parameters can be obtained. When the dropout parameter is 0.5 and the initial learning rate is 0.001, the recognition effect of the model established by GoogLeNet was optimal. According to the selected parameters, the training loss, testing loss, training recognition rate, and testing recognition rate of the model are all in line with expectations. Finally, the experimental recognition results show that the recognition rate of the proposed method is 97.38%, the recall rate is 86.1%, and the accuracy rate is 100% for the case of a 9:1 ratio of test data to training data, and the overall recognition effect of the proposed GoogLeNet is significantly better than that of vgg and Alexnet, which can effectively solve the problem of under-sampling of coal mine gas and coal dust explosion sounds and can meet the need for the intelligent recognition of coal mine gas and dust explosions.

Validation study of the Persian version of behavioral pathology in Alzheimer’s Disease Rating scale (BEHAVE-AD) and the empirical BHAVE-AD (E-BEHAVE-AD)

Introduction Behavioral and psychological symptoms of dementia (BPSD) are observed in more than 90% of patients with Alzheimer’s disease (AD). BPSDs are remediable if detected early and managed appropriately. Behavioral Pathology in Alzheimer’s disease Rating Scale (BEHAVE-AD) and Empirical BEHAVE-AD (E-BEHAVE-AD) were designed to identify BPSD. The aim of this study is to validate and prepare BEHAVE-AD and E-BEHAVE-AD in Persian language for clinical and research applications. Method 120 patients were selected through a combination of intentional and convenience sampling. All participants should fulfill the NINCDS-ADRDA Work Group criteria for a clinical diagnosis of Alzheimer’s disease. Functional Assessment Staging Tool (FAST) was used to determine the rate of AD progression. All patients were evaluated using the BEHAVE-AD and E-BEHAVE-AD questionnaires, as well as the Persian version of the Neuropsychiatric Inventory Questionnaire (NPI-Q) and Mini-Mental State Examination (MMSE). The Content Validity Index (CVI) is determined based on the compatibility of the Persian and the original version of the two scales according to the opinion of expert panels. Correlation of MMSE with BEHAVE-AD and E-BEHAVE-AD as well as the BPSD pattern on AD progression continuum by FAST were considered as indices of construct validity. Concurrent validity was estimated by correlating NPI-Q scores with BEHAVE-AD and E-BEHAVE-AD scores. For both scales, interrater reliability was extracted as a reliability index. Results Pearson correlation coefficients for the BEHAVE-AD scale were as follows: with NPI-Q (r = 0.77, p-value <0.01), with MMSE (r = −0.34, p-value <0.01), indicating concurrent and construct validity, respectively. The result for E-BEHAVE-AD was as follows: with NPI-Q-total (r = 0.59, p-value <0.01), and with MMSE (r = 0.31, p-value <0. 01). BEHAVE-AD and E-BEHAVE-AD scores increased in parallel with AD severity according to FAST, but not on the most severe AD stage. The area under the curve was estimated to be 0.84 (p-value <0.001) for BEHAVE-AD and 0.78 (p-value <0.001) for E-BEHAVE-AD. Correlation between BEHAVE-AD and E-BEHAVE-AD scores ranged from 0.45 to 0.63. The inter-rater reliability index ranged from 0.88 to 0.99 for BEHAVE-AD and from 0.74 to 0.95 for E-BEHAVE-AD. Conclusions The Persian version of BEHAVE-AD and E-BEHAVE-AD is valid and reliable for the assessment of BPSD in patients with AD.

Indoor thermal and humid stratification and statistical distribution in ice arenas

On-site measurements in four different ice arenas were carried out under multiple working conditions to study the indoor vertical temperature and humidity distributions. It's indicated that air distribution system has a great impact on the vertical profiles and brings about different inflection points. In order to achieve the same moisture level of around 3 g/kg in the occupied ice field, supply air humidity of jet ventilation should be reduced to 0.4 g/kg while that of ground displacement ventilation could be as high as 3.0 g/kg. The vertical profiles under different air distribution systems are simplified by calculating the air parameter discrepancy brought by dehumidification air supply in the present research. The discrepancy profile was characterized by Gaussian function with three shape coefficients. Based on the measured results, the variation of shape coefficients with different influencing factors was investigated. It is demonstrated that the extreme point coefficient can be estimated by the height of the air outlet, while the scaling range coefficient varied linearly with the relative air supply parameters. This study accumulated considerable measured data to comprehensively understand the current situation of temperature and humidity stratification in ice arenas. The proposed statistical variation distribution contributes to the precise environmental control and the efficient design of ice arenas.

Brief Version of the Frankfurt Emotional Work Scale and Gender Difference in Emotional Labour

This study was designed to assess the psychometric properties of a brief version of the Frankfurt Emotion Work Scale (FEWS) adapted to Spanish in a sample of teachers, taking into consideration gender differences. Method: The sample consisted of 9020 teachers of public education in the Valencian Community (Mage = 45.33 years, SD = 9.15; 72.5% female). Results: The psychometric properties are adequate. It consists of 12 items grouped into six factors that explain 79.54% of the variance. Cronbach’s alpha and composite reliability coefficients (CRC) for the full scale are adequate: α = 0.79; CRC = 0.90. Confirmatory Factorial Analyses also confirm the structure of the scale (χ2 = 890.36, S-B χ2 = 747.38, df = 39, NFI = 0.945, NNFI = 0.911, CFI = 0.947, IFI = 0.947, MFI = 0.925, and RMSEA = 0.069). Convergent and discriminant validity were also probed. Finally, a gender effect over Emotional labour was found, there was a difference between gender in the scale and all of the dimensions of the questionnaire, with higher values on women. Conclusions: according to the results of this study, the use of this diagnostic tool for Spanish non-university teachers appears to be justified.

Study on the mesh size determination method of blast wave numerical simulation with strong applicability

With the rapid development of computer hardware and software technology, numerical simulations have become one of the most important tools for studying propagation law of blast wave. Results of numerical simulations of explosion events greatly depend on the mesh size. The mesh size determination methods in the literature are relatively weak in generality. In this paper, a mesh size determination method with strong applicability is proposed. According to this method, the mesh size is the product of the scale coefficient and the third root of the equivalent TNT mass. The scale coefficient is related to the model dimension, scaled distance and simulation accuracy, and is independent of the TNT shape and the location of the detonation point. A large number of numerical simulation results confirm the accuracy of this method. The recommended scale coefficient to meet the engineering accuracy requirements is related to the model dimension and scaled distance. In general, when the scaled distance and model dimension are larger, the recommended scale coefficient will be larger. In this paper, the figures and tables of the recommended scale coefficients of 1D, 2D and 3D models varying with the scaled distance are given, and their rationality is verified by the existing numerical simulation events of blast wave. They can be used as a reference to determine the mesh size in numerical simulation of blast wave.

ESTABLISHMENT AND ANALYSIS OF FRACTAL CONTACT MODEL FOR POINT GRINDING PARTS

In this work, we establish a fractal contact model and analyze the effect of the parameters on stress. The study provided a method to make a link between contact characteristics and surface condition. The surface texture model was built based on the process mechanism of point grinding. The experiment for the effect of the surface texture on contour height was carried out on TR300 roughness shape-measuring instrument and the structural function method of fractal theory was used to obtain the fractal dimensions and scale coefficients of surfaces with different surface textures. The fractal contact model was established based on the fractal characteristics of the surface point ground and the simulation was carried out using Matlab. Furthermore, the validation of compression experiment was carried out by WAW-600C universal testing machine, the high-definition pictures before and after the experiment were obtained by KEYENCE VH-Z500R ultra-depth-of-field 3D microscope and the surface topographies before and after the experiment were obtained by NANOVEA PS50 three-dimensional noncontact surface profile meter. The obtained findings can help to choose appropriate surface with the best contact characteristics under certain condition.

Global quantum discord and von Neumann entropy in multipartite two-level atomic systems

We have computed the global quantum discord (GQD) and von Neumann entropy (VNE) of multipartite two-level atomic systems interacting with a single-mode Fock field. We use Tavis–Cumming model. We have explored how quantum correlations and quantum entanglement evolve with time in such systems. The quantum system is prepared initially in a mixed state and different parameters are varied to see how they affect the information processing in the system. The dynamical character of the GQD and VNE show an interplay between classical and nonclassical correlations. Photons in this model play an important role to assist the GQD and VNE and we observed that the effects of the field on the GQD and VNE reside in the time evolution of the system indicating that both atom and field states have become entangled. The GQD is assisted in a nonlinear fashion with the number of photons in the system. The GQD and VNE show linear behavior with each other in the dynamics of the system. The effects of intrinsic decoherence on the dynamics of the GQD and VNE are also studied. We have extrapolated the results for a large photon number on the system. We have studied the effect of the change in the size of the system on the maximum value of GQD and VNE and we have estimated the scaling coefficients for this behavior.

Canopy-MMD Text Clustering Algorithm Based on Simulated Annealing and Canopy Optimization

&lt;p&gt;Aiming at the problems that traditional K-means text clustering cannot automatically determine the number of clusters and is sensitive to initial cluster centers, this paper proposes a Canopy-MMD text clustering algorithm based on simulated annealing and silhouette coefficient optimization. The algorithm uses the simulated annealing algorithm combined with the silhouette coefficient to optimize the Canopy algorithm to find the optimal number of clusters, and uses the optimal number of clusters to determine the scale coefficient in the MMD algorithm, and finally achieves a better text clustering effect. The Sohu News dataset of Sogou Lab is experimentally analyzed and compared with the clustering results obtained by traditional K-means and algorithms in the literature. The experimental results show that the clustering performance of the algorithm is better than the traditional K-means algorithm and the algorithm in the literature, and the accuracy, precision, recall and F value are improved by 8.02%, 8.91%, 8.02%, 9.51% compared with the traditional K-means algorithm, which can be widely used in fields such as text mining, knowledge graph and natural language processing.&lt;/p&gt; &lt;p&gt;&amp;nbsp;&lt;/p&gt;

Development of a continuous spatiotemporal finite element-based representation of the mean sea surface

The mean sea surface (MSS) has an important role, both, in the calculation of the mean dynamic topography and in the area of sea-level change as a reference surface. This paper presents a new approach to estimate a continuous spatiotemporal MSS from along-track altimetric sea surface height measurements. A parametric function continuously defined in the spatial as well as temporal domain is constructed from a C^1-smooth finite element space to represent the MSS. Least-squares observation equations are set up, to estimate the unknown scaling coefficients from the sea surface height measurements as collected by altimetric exact repeat missions and geodetic missions. An advantage of the proposed method is that the surface is represented by an analytic model and the unknown parameters can be physically interpreted. Whereas the static component of the function represents the MSS, the temporal component is used to absorb the ocean variability. Within this initial study, 10 years of satellite altimetry over the period 2010–2019 are analyzed in a small study region around the Agulhas Current. To obtain the best possible data coverage, all missions available via AVISO, which provide data in the study region and period, are included, i.e., geodetic missions and mission phases as well as exact repeat missions. Besides the static MSS, the temporal component, which is co-estimated to absorb the dominating ocean variability, is modeled with different basis functions to study their performance. On the one hand, global basis functions considering a linear trend and periodic functions are compared with B-Spline basis functions. The comparison of the static component to the global CNES_CLS15 MSS shows a reasonable agreement with a root-mean-square error in the range of 1–4 cm for the well-suited model configurations. To validate the modeling approach and the different analyzed configurations, the temporal model component is compared to gridded sea-level anomaly products. Although it is not (yet) a target quantity, the analysis can serve as a quality check of the MSS and the proposed modeling approach as well. It is shown that in regions with relatively low ocean variability the combination of a linear trend with an annual period is well suited to model the dominant temporal signal, whereas it is not sufficient in regions with strong ocean variability, e.g., close to the Agulhas Current. In those regions, the scenario which utilizes B-Splines in the temporal domain performs significantly better. In general, it is demonstrated that the proposed approach can be an alternative to the well-established MSS estimation procedures.

Constructing Stronger and Faster Baselines for Skeleton-Based Action Recognition.

One essential problem in skeleton-based action recognition is how to extract discriminative features over all skeleton joints. However, the complexity of the recent State-Of-The-Art (SOTA) models for this task tends to be exceedingly sophisticated and over-parameterized. The low efficiency in model training and inference has increased the validation costs of model architectures in large-scale datasets. To address the above issue, recent advanced separable convolutional layers are embedded into an early fused Multiple Input Branches (MIB) network, constructing an efficient Graph Convolutional Network (GCN) baseline for skeleton-based action recognition. In addition, based on such the baseline, we design a compound scaling strategy to expand the model's width and depth synchronously, and eventually obtain a family of efficient GCN baselines with high accuracies and small amounts of trainable parameters, termed EfficientGCN-Bx, where "x" denotes the scaling coefficient. On two large-scale datasets, i.e., NTU RGB+D 60 and 120, the proposed EfficientGCN-B4 baseline outperforms other SOTA methods, e.g., achieving 92.1% accuracy on the cross-subject benchmark of NTU 60 dataset, while being 5.82× smaller and 5.85× faster than MS-G3D, which is one of the SOTA methods. The source code in PyTorch version and the pretrained models are available at https://github.com/yfsong0709/EfficientGCNv1.