An Empirical Study on Fertility Proposals Using Multi-Grained Topic Analysis Methods

Fertility issues are closely related to population security, in 60 years China's population for the first time in a negative growth trend, the change of fertility policy is of great concern to the community. 2023 "two sessions" proposal "suggests that the country in the form of legislation, the birth of the registration of the cancellation of the marriage restriction" This topic was once a hot topic on the Internet, and "unbundling" the relationship between birth registration and marriage has become the focus of social debate. In this paper, we adopt co-occurrence semantic analysis, topic analysis and sentiment analysis to conduct multi-granularity semantic analysis of microblog comments. It is found that the discussion on the proposal of "removing marriage restrictions from birth registration" involves the individual, society and the state at three dimensions, and is detailed into social issues such as personal behaviour, social ethics and law, and national policy, with people's sentiment inclined to be negative in most of the topics. Based on this, eight proposals were made to provide a reference for governmental decision making and to form a reference method for researching public opinion on political issues.Comment: 7 pages, 4 figures, 1 tabl

Performance analysis of end-to-end SNR estimators for AF relaying

Many existing signal-to-noise ratio (SNR) estimators were designed and evaluated for conventional one-hop communications systems. However, for a relaying system, it is the end-to-end SNR that determines the system performance. In this paper, we will fill this gap by evaluating the performances of the existing SNR estimators in a dual-hop relaying system used for each hop. The probability density functions of the SNR estimators are first derived, whose parameters are fitted as functions of the sample size and the true value of SNR. Using them, the cumulative distribution functions of the end-to-end SNR and the bit error rate performance for a relaying system are derived. Numerical results show that the squared signal-to-noise variance estimator has the best performance for small SNRs and the second-order fourth-order moments estimator has the best performance for large SNRs, while the signalto-variation ratio estimator has the worst performance, among the existing SNR estimators, for AF relaying systems

THE INFLUENCE OF COORDINATION BETWEEN UPPER LIMBS\u27 JOINTS ON SPORT LEVEL IN SNOOKER

This study explored the effect of coordination between upper limb joints on the technical level of shooting in billiards.Eight professional and eight amateur players were asked to shoot according to a specific rounte and vector coding method used to quantify the coordination of the motions of the limbs during the shooting stage.For coordination between the flexion and extension of shoulder and flexion and extension of elbow,the proportion of the anti-phase and elbow-phase coordination in the professional group was higher than the amateur group,and the proportion of the shoulder-phase was lower for professional than amateur group. For coordination of the flexion and extension of shoulder and the the adduction and outreach of wrist,the proportion of the wrist-phase coordination in the professional group was higher than the amateur group,and the proportion of the shoulder-phase was lower for the professional than amateur group.These indicators can be used as diagnostic indicators for snooker player\u27s shooting motio

ESTIMATION OF LOWER LIMB KINETICS FROM LANDMARKS DURING SIDESTEPPING VIA ARTIFICIAL NEURAL NETWORKS

The purpose of this study was to determine the validity of kinetics estimated from 3D coordinates of landmarks during sidestepping by artificial neural networks (ANN). 71 male college professional soccer athletes performed sidestepping with two directions (left and right) and two cutting angles (45° and 90°) 3times for every task, totally 12 times. Coordinates of reflective markers, ground reaction forces (GRF) and lower limb joint moments were measured. All 18 body landmarks such as joints center were obtained by reflective markers as inputs to estimate GRF and lower joint moments in the ANN whose type was multilayer perceptron. The most of kinetics estimated by ANN showed strong correlation(r\u3e0.9) with measured results. Just few kinetic curves of ANN existed significant differences in a few time points compared to measured results. ANN could accurately estimate kinetics from the coordinates of body landmarks druing sidestepping

Numerical study of divertor detachment in the MAST-U tokamak

Divertor detachment is a promising method to reduce heat loading and erosion in tokamak devices or even in future magnetic fusion reactors. In this thesis, two detachment regimes (increasing upstream density and seeding impurity) leading to the decrease of the divertor ion flux is numerically studied through modelling the super-X divertor in MAST-U like conditions. This thesis builds on previous work using the original SD1D modules of BOUT++, which is established to simulate parallel transport process from upstream to the target. We implement an upgrade in SD1D module by adding molecule-plasma interactions and impurity seeding in order to making simulations more self-consistent. To understand the role of molecules in density ramp detachment process, comparisons are made between the cases with different recycling conditions. It is found that if the recycling in divertor is more likely to produce neutral molecule, the roll-over of ion flux at the target occurs at a higher upstream density and a lower target temperature. We also find that molecule–plasma interactions are as crucial as atom–plasma interactions during divertor detachment, both of which account for the main plasma momentum loss. Molecule–plasma interactions can even cause a strong rise of Halpha signal in the detachment process, which agrees with the measurement on other devices (e.g TCV tokamak). The divertor detachment induced by seeding impurity (e.g. neon) is simulated in order to understand the difference between the two detachment regimes. It is found that increasing the puffing rate of neon impurity cannot quickly reduce the target temperature, thus the density of molecule species is small during detachment due to the high molecule dissociation rate, while atom-plasma interactions become dominant and account for the most of plasma momentum loss. Different from the density ramp induced detachment, we cannot find the strong rise of Halpha signal in this case

The Determinants of the Success of Crowdfunding

Crowdfunding allows the crowd to donate small amounts of money to entrepreneurs through online platforms. Comparing with traditional financial institutions, this new method facilitates the financing process through direct and easy online contact between initiators and investors. Based on the data obtained from Kickstarter, the largest crowdfunding platform, I investigated 27,117 crowdfunding projects from Jan 1st 2015 to Jun 30th 2015, and I find that a crowd funding campaign with a realistic funding goal, a suitable funding period, and more updates and interactions with investors, is much likely to be successfully funded. In addition, the different types of founders are very influential in crowdfunding outcomes. For example, females tend to collect funds more successfully than males do. Founders in the form of teams, companies or a specific project are also beneficial to funding outcomes

Multi-hop relaying using energy harvesting

In this letter, the performance of multi-hop relaying using energy harvesting is evaluated. Both amplify-and-forward and decode-and-forward relaying protocols are considered. The evaluation is conducted for time-switching energy harvesting as well as power-splitting energy harvesting. The largest number of hops given an initial amount of energy from the source node is calculated. Numerical results show that, in order to extend the network coverage using multi-hop relaying, time-switching is a better option than power splitting and in some cases, decode-and-forward also supports more hops than amplify-and-forward

Performance analysis of energy harvesting relaying

Recently, energy harvesting has been exploited as a key technique in wireless communications. Because conventional wireless systems are powered by batteries and cables, they tend to have restricted lifetime and flexibility. In order to solve these problems, wireless power has been investigated as a replacement for conventional batteries. This thesis focuses on energy harvesting in relaying. The data packet from the source to relay contains three parts: pilot for channel estimation, data symbols and pilots for harvesting. The data packet from the relay to the destination contains two parts: data symbols and pilots for estimation. To study energy harvesting, the performance of wireless powered communications is evaluated in terms of achievable rate and bit error rate, for applications where the downlink and the uplink are correlated, in contrast to previous works that assume independent uplink and downlink. Semi-closed expressions for the achievable rate and series expressions for the bit error rate are derived in Nakagami m fading channels, based on which the effect of link correlation is examined. Numerical results show that the link correlation has a significant impact on the achievable rate. Consequently, the optimum system parameter for correlated links is very different from that for independent links, showing the usefulness of our results. Also, the link correlation has a noticeable effect on the bit error rate, depending on the system parameters considered. Then, performance analysis has been performed for an AF relaying system with pilot-based channel estimation and time switching (TS) energy harvesting is conducted. Numerical results show the existence of the optimal values of the numbers of pilots for channel estimation and for energy harvesting, when the total size is fixed. Next, three novel structures using simultaneous wireless information and power transfer in energy harvesting amplify-and-forward (AF) relaying are investigated. Different combinations of time-switching (TS) and power-splitting (PS) energy harvesting protocols are studied. Closed-form expressions for the cumulative distribution function (CDF) of the end-to-end signal-to-noise ratio (SNR) for the three structures are derived. Using these expressions, achievable rate (AR) and bit-error-rate (BER) are derived. Different parameters are examined. Numerical results show the optimal splitting ratio for channel estimation, energy harvesting and data transmission, when the packet size is fixed. Finally, the energy from the source and the energy from the ambient are merged together. The three ambient structures are studied. The closed-form expressions for the cumulative distribution function (CDF) of the end-to-end signal-to- noise ratio (SNR) for the three ambient structures are derived. Curve fitting has been used to achieve the approximately achievable rate (AR) and bit-error-rate (BER). The results provide the optimal values for channel estimation pilots and power splitting ratio series for these ambient RF added structures

Homophily-Driven Sanitation View for Robust Graph Contrastive Learning

We investigate adversarial robustness of unsupervised Graph Contrastive Learning (GCL) against structural attacks. First, we provide a comprehensive empirical and theoretical analysis of existing attacks, revealing how and why they downgrade the performance of GCL. Inspired by our analytic results, we present a robust GCL framework that integrates a homophily-driven sanitation view, which can be learned jointly with contrastive learning. A key challenge this poses, however, is the non-differentiable nature of the sanitation objective. To address this challenge, we propose a series of techniques to enable gradient-based end-to-end robust GCL. Moreover, we develop a fully unsupervised hyperparameter tuning method which, unlike prior approaches, does not require knowledge of node labels. We conduct extensive experiments to evaluate the performance of our proposed model, GCHS (Graph Contrastive Learning with Homophily-driven Sanitation View), against two state of the art structural attacks on GCL. Our results demonstrate that GCHS consistently outperforms all state of the art baselines in terms of the quality of generated node embeddings as well as performance on two important downstream tasks

Experimental measurements of bulk modulus for two types of hydraulic oil at pressures to 140MPa and temperatures to 180°C

Bulk modulus of hydraulic oil represents the resistance of hydraulic oil to compression and is the reciprocal of compressibility. The bulk modulus is a basic thermodynamic property of hydraulic oil that has a very important influence on work efficiency and dynamic characteristics of hydraulic systems, especially for the hydraulic systems at ultra-high pressure or ultra-high temperature. In this study, a bulk modulus experimental equipment for hydraulic oil was designed and manufactured, two types of hydraulic oil were selected and its isothermal secant bulk modulus were measured at pressures to 140MPa and temperatures of 20~180°C. Compared the experimental results with the calculated results from the prediction equations of liquid bulk modulus that proposed by Klaus, Hayward, and Song, it is found that the experimental results are not completely identical with the calculated results