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Data-driven Smart Ponzi Scheme Detection [article]

Yuzhi Liang, Weijing Wu, Kai Lei, Feiyang Wang
2021 arXiv   pre-print
; Kai Lei, Weijing Wu, and Feiyang Wang are with ICNLab, Peking University, Shenzhen, China , and Peng Cheng Laboratory, Shenzhen, China.  ...  The existing smart Ponzi scheme detection methods can be broadly divided into detection methods based on source code inspection [5] , [6] Yuzhi Liang is with ICNLab, Peking University, Shenzhen, China  ... 
arXiv:2108.09305v1 fatcat:cn5q3o2oavb4biwb776rlaewse

Adaptive Technique for Underwater Acoustic Communication [chapter]

Shen Xiaohong, Wang Haiyan, Zhang Yuzhi, Zhao Ruiqi
2012 Underwater Acoustics  
Introduction Compared with the electromagnetic wave channel, the UWA (Underwater Acoustic) channel is characterized by large transmission delay, transmission loss increased with distance and frequency, serious multi-path effect, and remarkable Doppler Effect. These characteristics greatly influence the performance of UWA communication, and restrict channel capacity. Performance of UWA communication is far away from telecommunication, even if employ the similar techniques. Especially, available
more » ... andwidth is limited by spread distance because transmission loss increases with longer range distance. For example, the bandwidth for 5 km is 10 kHz whereas the bandwidth for 80 km is only 500Hz. For constant data rate, the bandwidth is confined by maximum working range and worst channel environment, so the utilization ratio of channel is very low. Besides the reasonable modulation model and advanced signal processing method which improves the detection performance of the receiver, the most fundamental way for reliable communication is adaptive modulation which greatly improves utilization ratio of bandwidth. Modulation and detection techniques used for UWA communication include phase coherent (PSK and QAM) and noncoherent (FSK) techniques. The choice of modulation mode is based on the UWA channel parameters, such as multipath and the Doppler spread, as well as the SNR. The spread factor of the UWA channel determines whether phase coherent communications are possible. If so, an equalizer is employed to combat any intersymbol interference. If the channel varies too rapidly, noncoherent signaling is chosen. The choice of modulation is determined by the operator. The objective of this chapter is based on the analysis of characteristics of UWA channel, developing algorithms that can self-adapting select the best technique for time varying UWA channel. Then the dynamic modulation and bandwidth optimization for high-rate UWA communication are deduced. At last the simulation results are shown. Fading characteristics of UWA channel 2.1 Characteristic of UWA channel Due to the absorption of medium itself, the wavefront expansion in sound propagation, the bending of acoustic ray, the scattering caused by various kinds of nonuniformity in ocean Underwater Acoustics 60 and so on, the acoustic intensity will weaken in its propagation direction. The fading will change with distance, frequency and sensors location, which can be divided into large-scale fading and small-scale fading.
doi:10.5772/33985 fatcat:wbiwfgcb3bbj5pyj7nvubmhvnu

Lightweight Single-Image Super-Resolution Network with Attentive Auxiliary Feature Learning [article]

Xuehui Wang, Qing Wang, Yuzhi Zhao, Junchi Yan, Lei Fan, Long Chen
2020 arXiv   pre-print
Despite convolutional network-based methods have boosted the performance of single image super-resolution (SISR), the huge computation costs restrict their practical applicability. In this paper, we develop a computation efficient yet accurate network based on the proposed attentive auxiliary features (A^2F) for SISR. Firstly, to explore the features from the bottom layers, the auxiliary feature from all the previous layers are projected into a common space. Then, to better utilize these
more » ... ed auxiliary features and filter the redundant information, the channel attention is employed to select the most important common feature based on current layer feature. We incorporate these two modules into a block and implement it with a lightweight network. Experimental results on large-scale dataset demonstrate the effectiveness of the proposed model against the state-of-the-art (SOTA) SR methods. Notably, when parameters are less than 320k, A^2F outperforms SOTA methods for all scales, which proves its ability to better utilize the auxiliary features. Codes are available at
arXiv:2011.06773v1 fatcat:5tfkqhy44fdazk4d6ageh42opy

Crystal Structure Prediction of Binary Alloys via Deep Potential

Haidi Wang, Yuzhi Zhang, Linfeng Zhang, Han Wang
2020 Frontiers in Chemistry  
We refer to Yanchao Wang and Ma (2012) for more details of the CALYPSO code.  ...  ., 2006) , the CALYPSO package (Wang et al., 2010) , and the PyChemia library (Avendaño-Franco and Romero, 2016) , respectively.  ...  Copyright © 2020 Wang, Zhang, Zhang and Wang. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY).  ... 
doi:10.3389/fchem.2020.589795 pmid:33330377 pmcid:PMC7732660 fatcat:62wa4xuipvbx3dcp6qo7tiaqvm

Optical Forces in Coupled Chiral Particles [article]

Kah Jen Wo, Jie Peng, Madhava Krishna Prasad, Yuzhi Shi, Jensen Li, Shubo Wang
2020 arXiv   pre-print
Structural chirality can induce counter-intuitive optical forces due to inherent symmetry properties. While optical forces on a single chiral particle in the Rayleigh regime have been well studied, optical forces in coupled chiral particles remain less explored. By using full-wave numerical simulations and analytical methods of source representation and coupled mode theory, we investigated the optical forces induced by a plane wave on two chiral particles coupling with each other via the
more » ... ent near fields. We found that the induced electric and magnetic dipoles of the chiral particles have complicated couplings that give rise to dark and bright modes. The interaction force between the particles can be either attractive or repulsive, and its magnitude can be significantly enhanced by the resonance modes. The attractive force is much stronger if two particles are of opposite handedness compared with the case of same handedness. The electric dipole force and the magnetic dipole force have the same sign for two particles with the same handedness, while they are of different signs for two particles with opposite handedness. The results can lead to a better understanding of chirality-induced optical forces with potential applications in optical manipulations and chiral light-matter interactions.
arXiv:2007.12443v1 fatcat:kcdxip4mn5a47nqv52i7knvbxq

First records of Hypsugo cadornae (Chiroptera: Vespertilionidae) in China

Huan-Wang Xie, Xingwen Peng, Chunlan Zhang, Jie Liang, Xiangyang He, Jian Wang, Junhua Wang, Yuzhi Zhang, Libiao Zhang
2020 Mammalia (Paris)  
AbstractHypsugo cadornae bats have been found in India, Myanmar, Thailand, Vietnam, Laos, and Cambodia. In 2017 and 2018, 15 medium size Hypsugo bats were collected from Shaoguan, Guangzhou, and Huizhou in Guangdong, China. Molecular and morphological examinations identified them as H. cadornae. This is the first record of H. cadornae in China. Morphological and ultrasonic characteristics of H. cadornae were compared with its close relative, Hypsugo pulveratus.
doi:10.1515/mammalia-2020-0029 fatcat:rlxqoqblffb4vjbep3ra5j7whm

Convergence of the Planewave Approximations for Quantum Incommensurate Systems [article]

Ting Wang, Huajie Chen, Aihui Zhou, Yuzhi Zhou, Daniel Massatt
2022 arXiv   pre-print
Incommensurate structures come from stacking the single layers of low-dimensional materials on top of one another with misalignment such as a twist in orientation. While these structures are of significant physical interest, they pose many theoretical challenges due to the loss of periodicity. This paper studies the spectrum distribution of incommensurate Schrödinger operators. We characterize the density of states for the incommensurate system and develop novel numerical methods to approximate
more » ... them. In particular, we (i) justify the thermodynamic limit of the density of states in the real space formulation; and (ii) propose efficient numerical schemes to evaluate the density of states based on planewave approximations and reciprocal space sampling. We present both rigorous analysis and numerical simulations to support the reliability and efficiency of our numerical algorithms.
arXiv:2204.00994v1 fatcat:fbrnax4otnhmropkhhrz7dxy7m

Fractional matching preclusion for butterfly derived networks

Xia Wang, Tianlong Ma, Chengfu Ye, Yuzhi Xiao, Fang Wang
2019 Theory and Applications of Graphs  
Digital Commons@Georgia Southern, 2019 Theory and Applications of Graphs, Vol. 6 [2019], Iss. 1, Art. 3 DOI: 10.20429/tag.2019.060103 Wang  ... 
doi:10.20429/tag.2019.060103 fatcat:ifbgs3ggfjfi7jrc6qmojxgaei

Orientation Ordering and Chiral Superstructures in Fullerene Monolayer on Cd (0001)

Yuzhi Shang, Zilong Wang, Daxiao Yang, Yaru Wang, Chaoke Ma, Minlong Tao, Kai Sun, Jiyong Yang, Junzhong Wang
2020 Nanomaterials  
The structure of C60 thin films grown on Cd (0001) surface has been investigated from submonolayer to second monolayer regimes with a low-temperature scanning tunneling microscopy (STM). There are different C60 domains with various misorientation angles relative to the lattice directions of Cd (0001). In the (2√3 × 2√3) R30° domain, orientational disorder of the individual C60 molecules with either pentagon, hexagon, or 6:6 bond facing up has been observed. However, orientation ordering
more » ... in the R26° domain such that all the C60 molecules adopt the same orientation with the 6:6 bond facing up. In particular, complex chiral motifs composed of seven C60 molecules with clockwise or anticlockwise handedness have been observed in the R4° and R8° domains, respectively. Scanning tunneling spectroscopy (STS) measurements reveal a reduced HOMO–LOMO gap of 2.1 eV for the C60 molecules adsorbed on Cd (0001) due to the substrate screening and charge transfer from Cd to C60 molecules.
doi:10.3390/nano10071305 pmid:32635309 fatcat:pe5425pqwra7jehrnooj5f3i6m

Depression after minor stroke: Prevalence and predictors

YuZhi Shi, YuTao Xiang, Yang Yang, Ning Zhang, Shuo Wang, Gabor S. Ungvari, Helen F.K. Chiu, Wai Kwong Tang, YiLong Wang, XingQuan Zhao, YongJun Wang, ChunXue Wang
2015 Journal of Psychosomatic Research  
Acknowledgments -11 - The authors would like to thank all of the participating hospitals and colleagues, particularly Tong Zhang, Yong Zhou, Ying Bai, Juan Zhou, De-Jun Liang, Li-Ping Liu, Gai-Fen Liu, An-Xin Wang  ... 
doi:10.1016/j.jpsychores.2015.03.012 pmid:25868687 fatcat:dx7kd5u7yjdtxkisclarejbgua

Application of the Phase Space Reconstruction in Ecology

Yuzhi Wang, Bo Li, Renqing Wang, Jing Su, Xiaoxia Rong
2010 Mathematical and Computational Applications  
A brief introduction to phase space reconstruction in ecology is given, and the application of the method to rodent populations is illustrated. Results show that phase space reconstruction is highly convenient and effective when utilized in short-term predictions in natural population.
doi:10.3390/mca15050872 fatcat:h2l3jszmd5gojmeo76kvdxsa2y

Transilient Response to Acetone Gas Using the Interlocking p+n Field-Effect Transistor Circuit

Xinyuan Zhou, Jinxiao Wang, Zhou Wang, Yuzhi Bian, Ying Wang, Ning Han, Yunfa Chen
2018 Sensors  
Low concentration acetone gas detection is significantly important for diabetes diagnosis as 1.8-10 ppm of acetone exists in exhaled breath from diabetes patients. A new interlocking p+n field-effect transistor (FET) circuit has been proposed for Mn-doped ZnO nanoparticles (MZO) to detect the acetone gas at low concentration, especially close to 1.8 ppm. It is noteworthy that MZO in this interlocking amplification circuit shows a low voltage signal of <0.3 V to the acetone <2 ppm while it
more » ... ys a transilient response with voltage signal >4.0 V to >2 ppm acetone. In other words, the response to acetone from 1 ppm to 2 ppm increases by~1233%, which is competent to separate diabetic patients from healthy people. Moreover, the response to 2 ppm acetone is hardly influenced by high relative humidity of 85%. In the meanwhile, MZO in this interlocking circuit possesses a high acetone selectivity compared to formaldehyde, acetaldehyde, toluene and ethanol, suggesting a promising technology for the widespread qualitative screening of diabetes. Importantly, this interlocking circuit is also applicable to other types of metal oxide semiconductor gas sensors. The resistance jump of p-and n-FETs induced by the change of their gate voltages is deemed to make this interlocking circuit produce the transilient response.
doi:10.3390/s18061914 pmid:29895805 pmcid:PMC6021865 fatcat:iuuacd62brdqpk6son62e4vsdy

Preparation and Nutritional Characterization of Perilla Chewable Tablet

Jinhong Wu, Chunmei Yang, Yuzhi Rong, Zhengwu Wang
2012 Procedia Engineering  
In this study, the preparation and trophic characterization of perilla chewable tablet were investigated. Perilla chewable tablet was prepared according to the following process: mixing perilla raw materials with excipients, making wet granules, drying, tabletting and coating. The optimal formula was determined as follows: 8% perilla powder, 2.5% perilla extract powder, 20% isomaltooligosaccharide, 20% microcrystalline cellulose, 44.4% lactose, 0.5% essence of perilla, 0.1% sucralose, 2%
more » ... tol, 2% vitamin C, 0.5% magnesium stearate. Results from nutrient analysis showed that perilla chewable tablet was rich in essential vitamins and mineral substances, which are good for human health.
doi:10.1016/j.proeng.2012.04.227 fatcat:ig3qxm6ezbfthjpxhvzfr5kzrm

GoHop: Personal VPN to defend from censorship

Yuzhi Wang, Ping Ji, Borui Ye, Pengjun Wang, Rong Luo, Huazhong Yang
2014 16th International Conference on Advanced Communication Technology  
Internet censorship threatens people's online privacy, and in recent years, new technologies such as high-speed Deep Packet Inspection (DPI) and statistical traffic analysis methods had been applied in country scale censorship and surveillance projects. Traditional encryption protocols cannot hide statistical flow properties and new censoring systems can easily detect and block them "in the dark". Recent work showed that traffic morphing and protocol obfuscation are effective ways to defend
more » ... statistical traffic analysis. In this paper, we proposed a novel traffic obfuscation protocol, where client and server communicate on random port. We implemented our idea as an open-source VPN tool named GoHop, and developed several obfuscation method including preshared key encryption, traffic shaping and random port communication. Experiments has shown that GoHop can successfully bypass internet censoring systems, and can provide high-bandwidth network throughput.
doi:10.1109/icact.2014.6778916 fatcat:sgf3cdjfmrhd5aswnma2w5652q

Modeling V1 Disparity Tuning to Time-Varying Stimuli

Yuzhi Chen, Yunjiu Wang, Ning Qian
2001 Journal of Neurophysiology  
Wang was supported by Grants 69835020, 39670186, and 39893340-06 from the National Natural Science Foundation of China.  ... 
doi:10.1152/jn.2001.86.1.143 pmid:11431496 fatcat:3a57xdagrvgwnfb6t6fj2fwmi4
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