![](https://dblp.uni-trier.de./img/logo.320x120.png)
![search dblp search dblp](https://dblp.uni-trier.de./img/search.dark.16x16.png)
![search dblp](https://dblp.uni-trier.de./img/search.dark.16x16.png)
default search action
Zijian Liu
This is just a disambiguation page, and is not intended to be the bibliography of an actual person. Any publication listed on this page has not been assigned to an actual author yet. If you know the true author of one of the publications listed below, you are welcome to contact us.
Person information
Refine list
![note](https://dblp.uni-trier.de./img/note-mark.dark.12x12.png)
refinements active!
zoomed in on ?? of ?? records
view refined list in
export refined list as
2020 – today
- 2025
- [j54]Yu Mu, Wing-Cheong Lo, Yuanshun Tan, Zijian Liu:
Hybrid control for the prey in a spatial prey-predator model with cooperative hunting and fear effect time lag. Appl. Math. Comput. 491: 129217 (2025) - 2024
- [j53]Haiqing Zhang, Zijian Liu
, Yuanshun Tan, Yu Mu:
A stochastic predator-prey eco-epidemiological model with hunting cooperation. Appl. Math. Lett. 157: 109201 (2024) - [j52]Zijian Liu
, Yaning Wang, Yang Luo
, Chunbo Luo:
Graph-based few-shot incremental learning algorithm for unknown class detection. Appl. Soft Comput. 154: 111363 (2024) - [j51]Han Li, Zijian Liu, Kai Yang
, Xiaogang Dong, Wenshan Wang:
A pth-order random coefficients mixed binomial autoregressive process with explanatory variables. Comput. Stat. 39(5): 2581-2604 (2024) - [j50]Xitong Pu
, Chunbo Luo
, Yihao Yin, Zijian Liu
, Yang Luo
:
Chromosomal Mutation-Inspired Radio Augmentation for Enhanced Automatic Modulation Classification. IEEE Internet Things J. 11(24): 41124-41136 (2024) - [j49]Zijian Liu
, Xiaoheng Deng
, Ping Jiang
, Conghao Lv, Geyong Min
, Xin Wang:
Edge Perception Camouflaged Object Detection Under Frequency Domain Reconstruction. IEEE Trans. Circuits Syst. Video Technol. 34(10): 10194-10207 (2024) - [j48]Junhan Xie
, Yang Luo
, Haifen Yang, Zijian Liu
, Chunbo Luo
:
A Dynamic Group-Connected Design With True-Time-Delay for Wideband THz Beamforming. IEEE Trans. Veh. Technol. 73(1): 1441-1446 (2024) - [j47]Zijian Liu
, Chunbo Luo
, Junhan Xie
, Yang Luo
:
A Synchronous Training Hypergraph Neural Network for Power Allocation in Multi-Cell Multi-User Networks. IEEE Wirel. Commun. Lett. 13(4): 1113-1117 (2024) - [c23]Zijian Liu
, Ping Jiang, Lixin Lin, Xiaoheng Deng:
Edge Attention Learning for Efficient Camouflaged Object Detection. ICASSP 2024: 5230-5234 - [c22]Zijian Liu, Zhengyuan Zhou:
Revisiting the Last-Iterate Convergence of Stochastic Gradient Methods. ICLR 2024 - [c21]Junyi Fan, Yuxuan Han, Zijian Liu, Jian-Feng Cai, Yang Wang, Zhengyuan Zhou:
On the Convergence of Projected Bures-Wasserstein Gradient Descent under Euclidean Strong Convexity. ICML 2024 - [c20]Zijian Liu, Zhengyuan Zhou:
On the Last-Iterate Convergence of Shuffling Gradient Methods. ICML 2024 - [c19]Liwei Liu, Zijian Liu, Na Ruan:
From the Perspective of Prototypes: A Privacy-Preserving Personalized Federated Learning Framework. ISPEC 2024: 222-239 - [i11]Zijian Liu, Zhengyuan Zhou:
On the Last-Iterate Convergence of Shuffling Gradient Methods. CoRR abs/2403.07723 (2024) - [i10]Zijian Liu, Zhengyuan Zhou:
Nonconvex Stochastic Optimization under Heavy-Tailed Noises: Optimal Convergence without Gradient Clipping. CoRR abs/2412.19529 (2024) - 2023
- [j46]Gang Su, Changchun Ding, Sida Li, Zijian Liu, Zheng Gao, Junfeng Song
, Shuxu Guo
, Min Tao
:
A Method for Generating True Random Numbers With Multiple Distribution Characteristics. IEEE Access 11: 81753-81762 (2023) - [j45]Zijian Liu, Wende Tian
, Bin Liu
, Zhe Cui:
A novel dynamic distance coding identification method for oil-gas gathering and transportation process. Eng. Appl. Artif. Intell. 121: 106010 (2023) - [j44]Zijian Liu
, Weilong Ding, Tao Chen, Maoxiang Sun, Hongmin Cai, Chen Liu:
A electricity theft detection method through contrastive learning in smart grid. EURASIP J. Wirel. Commun. Netw. 2023(1): 54 (2023) - [j43]Zhonghu Luo, Zijian Liu
, Yuanshun Tan:
Stability and Hopf Bifurcation Analysis for an Age-Structured Tumor Immune Model with Time Delay. Int. J. Bifurc. Chaos 33(7): 2350077:1-2350077:16 (2023) - [j42]Qianjun Chen, Zijian Liu, Yuanshun Tan, Jin Yang:
Analysis of a stochastic hybrid population model with impulsive perturbations and Allee effect. J. Appl. Math. Comput. 69(1): 565-587 (2023) - [j41]Zijian Liu, Zhonghu Luo, Yuanshun Tan, Jianhua Pang, Jing Chen
:
Mathematical models and dynamic behaviors of cancer treatment by continuous and pulsed radiotherapy. J. Appl. Math. Comput. 69(2): 1819-1843 (2023) - [j40]Jin Yang, Zhuo Chen, Yuanshun Tan, Zijian Liu, Robert A. Cheke
:
Threshold dynamics of an age-structured infectious disease model with limited medical resources. Math. Comput. Simul. 214: 114-132 (2023) - [j39]Zijian Liu
, Yang Luo
, Xitong Pu
, Geyong Min
, Chunbo Luo
:
A Multi-Modal Hypergraph Neural Network via Parametric Filtering and Feature Sampling. IEEE Trans. Big Data 9(5): 1365-1379 (2023) - [j38]Bing Li, Peng Yang, Hanlin Zhao, Penghui Zhang, Zijian Liu:
Hierarchical Sliding Inference Generator for Question-driven Abstractive Answer Summarization. ACM Trans. Inf. Syst. 41(1): 7:1-7:27 (2023) - [c18]Zijian Liu, Jiawei Zhang, Zhengyuan Zhou:
Breaking the Lower Bound with (Little) Structure: Acceleration in Non-Convex Stochastic Optimization with Heavy-Tailed Noise. COLT 2023: 2266-2290 - [c17]Zijian Liu
, Michita Imai
:
Telepresence Chameleon: Improve User Experience of Telepresence Robot With Chameleon Effect. HAI 2023: 55-62 - [c16]Zijian Liu, Ta Duy Nguyen, Alina Ene, Huy L. Nguyen:
On the Convergence of AdaGrad(Norm) on ℝd: Beyond Convexity, Non-Asymptotic Rate and Acceleration. ICLR 2023 - [c15]Zijian Liu, Ta Duy Nguyen, Thien Hang Nguyen, Alina Ene
, Huy Nguyen:
High Probability Convergence of Stochastic Gradient Methods. ICML 2023: 21884-21914 - [c14]Maoxiang Sun, Weilong Ding, Tianpu Zhang, Zijian Liu, Mengda Xing, Jihai Huang:
STDA-Meta: A Meta-Learning Framework for Few-Shot Traffic Prediction. ICPADS 2023: 534-541 - [i9]Zijian Liu, Perry Dong, Srikanth Jagabathula, Zhengyuan Zhou:
Near-Optimal High-Probability Convergence for Non-Convex Stochastic Optimization with Variance Reduction. CoRR abs/2302.06032 (2023) - [i8]Zijian Liu, Jiawei Zhang, Zhengyuan Zhou:
Breaking the Lower Bound with (Little) Structure: Acceleration in Non-Convex Stochastic Optimization with Heavy-Tailed Noise. CoRR abs/2302.06763 (2023) - [i7]Zijian Liu, Ta Duy Nguyen, Thien Hang Nguyen, Alina Ene, Huy Le Nguyen:
High Probability Convergence of Stochastic Gradient Methods. CoRR abs/2302.14843 (2023) - [i6]Zijian Liu, Zhengyuan Zhou:
Stochastic Nonsmooth Convex Optimization with Heavy-Tailed Noises. CoRR abs/2303.12277 (2023) - [i5]Maoxiang Sun, Weilong Ding, Tianpu Zhang, Zijian Liu, Mengda Xing:
STDA-Meta: A Meta-Learning Framework for Few-Shot Traffic Prediction. CoRR abs/2310.20223 (2023) - [i4]Zijian Liu, Zhengyuan Zhou:
Revisiting the Last-Iterate Convergence of Stochastic Gradient Methods. CoRR abs/2312.08531 (2023) - 2022
- [j37]Zhixin Liu, Zijian Liu, Yuanai Xie, Kit Yan Chan, Yazhou Yuan, Yi Yang:
Power allocation in D2D enabled cellular network with probability constraints: A robust Stackelberg game approach. Ad Hoc Networks 133: 102891 (2022) - [j36]Zijian Liu
, Yang Luo
, Yan Xu
, Chunbo Luo:
A Deep Constrained and Synchronous Training Framework for Hybrid Precoding. IEEE Commun. Lett. 26(6): 1288-1292 (2022) - [j35]Likun Guan, Jin Yang
, Yuanshun Tan, Zijian Liu, Robert A. Cheke:
Bifurcation Analysis of a Tumour-Immune Model with Nonlinear Killing Rate as State-Dependent Feedback Control. Int. J. Bifurc. Chaos 32(10): 2250155:1-2250155:19 (2022) - [j34]Yi Wu, Delong Zhu, Zijian Liu, Xin Li:
An Improved BPNN Algorithm Based on Deep Learning Technology to Analyze the Market Risks of A+H Shares. J. Glob. Inf. Manag. 30(7): 1-23 (2022) - [j33]Peng Yang, Zijian Liu, Bing Li, Penghui Zhang:
Implicit Relation Inference with Deep Path Extraction for Commonsense Question Answering. Neural Process. Lett. 54(6): 4751-4768 (2022) - [j32]Yaning Wang, Zijian Liu
, Yang Luo
, Chunbo Luo:
A transductive learning method to leverage graph structure for few-shot learning. Pattern Recognit. Lett. 159: 189-195 (2022) - [j31]Yi Yang, Zijian Liu, Zhixin Liu
, Yuanai Xie, Kit Yan Chan
, Xinping Guan
:
Joint Optimization of Edge Computing Resource Pricing and Wireless Caching for Blockchain-Driven Networks. IEEE Trans. Veh. Technol. 71(6): 6661-6670 (2022) - [c13]Zijian Liu, Bingfeng Zhang, Cheng Xu, Yuansheng Liu, Jun Zhang:
Vision localization method for intelligent vehicles in low-texture environments. CIS 2022: 243-247 - [c12]Zijian Liu, Qinxun Bai, Jose H. Blanchet, Perry Dong, Wei Xu, Zhengqing Zhou, Zhengyuan Zhou:
Distributionally Robust Q-Learning. ICML 2022: 13623-13643 - [c11]Zijian Liu, Ta Duy Nguyen, Alina Ene, Huy L. Nguyen:
Adaptive Accelerated (Extra-)Gradient Methods with Variance Reduction. ICML 2022: 13947-13994 - [i3]Zijian Liu, Ta Duy Nguyen, Alina Ene, Huy L. Nguyen:
Adaptive Accelerated (Extra-)Gradient Methods with Variance Reduction. CoRR abs/2201.12302 (2022) - [i2]Zijian Liu, Ta Duy Nguyen, Alina Ene
, Huy L. Nguyen:
On the Convergence of AdaGrad on $\R^{d}$: Beyond Convexity, Non-Asymptotic Rate and Acceleration. CoRR abs/2209.14827 (2022) - [i1]Zijian Liu, Ta Duy Nguyen, Thien Hang Nguyen, Alina Ene, Huy L. Nguyen:
META-STORM: Generalized Fully-Adaptive Variance Reduced SGD for Unbounded Functions. CoRR abs/2209.14853 (2022) - 2021
- [j30]Lin Chen
, Jin Yang, Yuanshun Tan, Zijian Liu, Robert A. Cheke
:
Threshold dynamics of a stochastic model of intermittent androgen deprivation therapy for prostate cancer. Commun. Nonlinear Sci. Numer. Simul. 100: 105856 (2021) - [j29]Yongjun Xu, Zijian Liu, Chongwen Huang
, Chau Yuen
:
Robust Resource Allocation Algorithm for Energy-Harvesting-Based D2D Communication Underlaying UAV-Assisted Networks. IEEE Internet Things J. 8(23): 17161-17171 (2021) - [j28]Huan Yang
, Yuanshun Tan, Jin Yang, Zijian Liu:
Extinction and persistence of a tumor-immune model with white noise and pulsed comprehensive therapy. Math. Comput. Simul. 182: 456-470 (2021) - [c10]Xinxing Chen
, Zijian Liu, Jiale Zhu, Kuangen Zhang
, Yuquan Leng, Chenglong Fu:
Comparison of machine learning regression algorithms for foot placement prediction. M2VIP 2021: 169-174 - [c9]Yongjun Xu, Zijian Liu, Zhaohui Yang, Chongwen Huang:
Energy-Efficient Resource Allocation with Imperfect CSI in NOMA-based D2D Networks with SWIPT. WCNC 2021: 1-6 - 2020
- [j27]Shan He
, Xin Sui
, Zijian Liu, Min Kang, Dao Zhou, Frede Blaabjerg
:
Torque Ripple Minimization of a Five-Phase Induction Motor Under Open-Phase Faults Using Symmetrical Components. IEEE Access 8: 114675-114691 (2020) - [j26]Kunpeng Zhang
, Liang Zheng
, Zijian Liu, Ning Jia:
A deep learning based multitask model for network-wide traffic speed prediction. Neurocomputing 396: 438-450 (2020) - [j25]Zijian Liu, Chang Shu
, Shiyi Chen
, Liming Yang, Minping Wan, W. Liu:
A novel solver for simulation of flows from continuum regime to rarefied regime at moderate Knudsen number. J. Comput. Phys. 415: 109548 (2020) - [j24]Kunpeng Zhang
, Zijian Liu, Liang Zheng
:
Short-Term Prediction of Passenger Demand in Multi-Zone Level: Temporal Convolutional Neural Network With Multi-Task Learning. IEEE Trans. Intell. Transp. Syst. 21(4): 1480-1490 (2020) - [c8]Carmine Tommaso Recchiuto, Luna Gava
, Lucrezia Grassi
, Alberto Grillo, Marta Lagomarsino
, Davide Lanza
, Zijian Liu, Chris Papadopoulos, Irena Papadopoulos, Antonello Scalmato, Antonio Sgorbissa:
Cloud Services for Culture Aware Conversation: Socially Assistive Robots and Virtual Assistants. UR 2020: 270-277
2010 – 2019
- 2019
- [j23]Zijian Liu
, Zaiping Nie
:
Subspace-Based Variational Born Iterative Method for Solving Inverse Scattering Problems. IEEE Geosci. Remote. Sens. Lett. 16(7): 1017-1020 (2019) - [j22]Zijian Liu
:
A New Scheme Based on Born Iterative Method for Solving Inverse Scattering Problems With Noise Disturbance. IEEE Geosci. Remote. Sens. Lett. 16(7): 1021-1025 (2019) - [c7]Huan Wang
, Guotai Wang
, Zijian Liu, Shaoting Zhang:
Global and Local Multi-scale Feature Fusion Enhancement for Brain Tumor Segmentation and Pancreas Segmentation. BrainLes@MICCAI (1) 2019: 80-88 - 2018
- [j21]Huan Qin, Yi Guo, Zijian Liu, Yu Liu, Haolong Zhong:
Shape optimization of automotive body frame using an improved genetic algorithm optimizer. Adv. Eng. Softw. 121: 235-249 (2018) - [j20]Zijian Liu, Jing Chen
, Jianhua Pang, Ping Bi, Shigui Ruan:
Modeling and Analysis of a Nonlinear Age-Structured Model for Tumor Cell Populations with Quiescence. J. Nonlinear Sci. 28(5): 1763-1791 (2018) - [j19]Zaiping Nie
, Zijian Liu, Xiangyang Sun:
A Multirelay Cooperation Method for Wireless Transmission of MWD and LWD Signals. IEEE Trans. Geosci. Remote. Sens. 56(3): 1229-1237 (2018) - 2017
- [j18]Huan Qin, Zijian Liu, Yu Liu, Haolong Zhong:
An object-oriented MATLAB toolbox for automotive body conceptual design using distributed parallel optimization. Adv. Eng. Softw. 106: 19-32 (2017) - [j17]Ping Bi
, Zijian Liu
, Mutei Damaris Muthoni, Jianhua Pang:
The Dynamical Behaviors for a Class of Immunogenic Tumor Model with Delay. Comput. Math. Methods Medicine 2017: 1642976:1-1642976:9 (2017) - [j16]Fang Dong
, Pengcheng Zhou, Zijian Liu, Dian Shen, Zhuqing Xu, Junzhou Luo
:
Towards a fast and secure design for enterprise-oriented cloud storage systems. Concurr. Comput. Pract. Exp. 29(19) (2017) - [j15]Chenxue Yang, Mao Ye
, Song Tang, Tao Xiang, Zijian Liu:
Semi-supervised low-rank representation for image classification. Signal Image Video Process. 11(1): 73-80 (2017) - [c6]Jianhua Pang, Yuqian Zhao, Fengchao Lu, Zijian Liu, Ping Bi:
Global analysis of a dengue fever model with quarantine. ICNC-FSKD 2017: 978-982 - 2016
- [j14]Zijian Liu, Chenxue Yang:
A mathematical model of cancer treatment by radiotherapy followed by chemotherapy. Math. Comput. Simul. 124: 1-15 (2016) - [c5]Zijian Liu, Fang Dong, Junxue Zhang, Pengcheng Zhou, Zhuqing Xu, Junzhou Luo:
A client-side directory prefetching mechanism for GlusterFS. SMC 2016: 3942-3947 - 2015
- [c4]Jingbo Chen, Zijian Liu:
Robust variance control for a class of nonlinear discrete systems with uncertainties and time-delay. ICCAIS 2015: 454-457 - 2014
- [j13]Lanbo Liu, Zijian Liu, Hao Xie, Benjamin Barrowes, Amvrossios C. Bagtzoglou
:
Numerical simulation of UWB impulse radar vital sign detection at an earthquake disaster site. Ad Hoc Networks 13: 34-41 (2014) - [j12]Zijian Liu
, Chenxue Yang:
A Mathematical Model of Cancer Treatment by Radiotherapy. Comput. Math. Methods Medicine 2014: 172923:1-172923:12 (2014) - [j11]Zijian Liu, Shouming Zhong, Xiaoyun Liu:
Permanence and periodic solutions for an impulsive reaction-diffusion food-chain system with ratio-dependent functional response. Commun. Nonlinear Sci. Numer. Simul. 19(1): 173-188 (2014) - 2013
- [j10]Zijian Liu, Shouming Zhong, Zhidong Teng, Long Zhang
:
Permanence and global attractivity of an impulsive ratio-dependent predator-prey system in a patchy environment. Appl. Math. Comput. 219(18): 9791-9804 (2013) - [j9]Chenxue Yang, Mao Ye
, Zijian Liu
:
An Impulsive Periodic Single-Species Logistic System with Diffusion. J. Appl. Math. 2013: 101238:1-101238:9 (2013) - [j8]Zijian Liu, Lanbo Liu, Yuan Xu, Lihong Victory Wang
:
Transcranial Thermoacoustic Tomography: A Comparison of Two Imaging Algorithms. IEEE Trans. Medical Imaging 32(2): 289-294 (2013) - [c3]Zijian Liu, Lei Xu:
A Detective Tool against SQL Injection Attacks Based on Static Analysis and Dynamic Monitor. IEEE WISA 2013: 195-198 - 2012
- [j7]Shaohua Long, Shouming Zhong, Zijian Liu:
Stochastic admissibility for a class of singular Markovian jump systems with mode-dependent time delays. Appl. Math. Comput. 219(8): 4106-4117 (2012) - [j6]Shaohua Long, Shouming Zhong, Zijian Liu:
H∞ filtering for a class of singular Markovian jump systems with time-varying delay. Signal Process. 92(11): 2759-2768 (2012) - 2011
- [j5]Zijian Liu, Shouming Zhong, Chun Yin, Wufan Chen:
Permanence, extinction and periodic solutions in a mathematical model of cell populations affected by periodic radiation. Appl. Math. Lett. 24(10): 1745-1750 (2011) - [j4]Zijian Liu, Shouming Zhong, Xiaoyun Liu:
Permanence and periodic solutions for an impulsive reaction-diffusion food-chain system with holling type III functional response. J. Frankl. Inst. 348(2): 277-299 (2011) - [j3]Chun Yin, Shouming Zhong, Xiaoyun Liu, Zijian Liu:
Novel Delay-Dependent Stabilization Criterion for Lur'e Systems with Sector-Restricted Nonlinearities and External Disturbances via PD Feedback Approach. J. Optim. Theory Appl. 151(1): 81-99 (2011) - [j2]Lanbo Liu, Zijian Liu, Benjamin E. Barrowes:
Through-Wall Bio-Radiolocation With UWB Impulse Radar: Observation, Simulation and Signal Extraction. IEEE J. Sel. Top. Appl. Earth Obs. Remote. Sens. 4(4): 791-798 (2011) - [c2]Lanbo Liu, Hao Xie, Zijian Liu, Amvrossios C. Bagtzoglou, Benjamin Barrowes, Antonio M. Vincitore:
Numerical simulation of UWB impulse radar vital signal detection at an earthquake disaster site. ACWR 2011: 278-281 - 2010
- [j1]Zijian Liu, Shouming Zhong:
Permanence and extinction analysis for a delayed periodic predator-prey system with Holling type II response function and diffusion. Appl. Math. Comput. 216(10): 3002-3015 (2010)
2000 – 2009
- 2008
- [c1]Yinxue Zhang, Zhenhong Jia, Haijun Jiang, Zijian Liu:
Image Restoration Based on Robust Error Function and Particle Swarm Optimization-BP Neural Network. ICNC (7) 2008: 640-644
Coauthor Index
![](https://dblp.uni-trier.de./img/cog.dark.24x24.png)
manage site settings
To protect your privacy, all features that rely on external API calls from your browser are turned off by default. You need to opt-in for them to become active. All settings here will be stored as cookies with your web browser. For more information see our F.A.Q.
Unpaywalled article links
Add open access links from to the list of external document links (if available).
Privacy notice: By enabling the option above, your browser will contact the API of unpaywall.org to load hyperlinks to open access articles. Although we do not have any reason to believe that your call will be tracked, we do not have any control over how the remote server uses your data. So please proceed with care and consider checking the Unpaywall privacy policy.
Archived links via Wayback Machine
For web page which are no longer available, try to retrieve content from the of the Internet Archive (if available).
Privacy notice: By enabling the option above, your browser will contact the API of archive.org to check for archived content of web pages that are no longer available. Although we do not have any reason to believe that your call will be tracked, we do not have any control over how the remote server uses your data. So please proceed with care and consider checking the Internet Archive privacy policy.
Reference lists
Add a list of references from ,
, and
to record detail pages.
load references from crossref.org and opencitations.net
Privacy notice: By enabling the option above, your browser will contact the APIs of crossref.org, opencitations.net, and semanticscholar.org to load article reference information. Although we do not have any reason to believe that your call will be tracked, we do not have any control over how the remote server uses your data. So please proceed with care and consider checking the Crossref privacy policy and the OpenCitations privacy policy, as well as the AI2 Privacy Policy covering Semantic Scholar.
Citation data
Add a list of citing articles from and
to record detail pages.
load citations from opencitations.net
Privacy notice: By enabling the option above, your browser will contact the API of opencitations.net and semanticscholar.org to load citation information. Although we do not have any reason to believe that your call will be tracked, we do not have any control over how the remote server uses your data. So please proceed with care and consider checking the OpenCitations privacy policy as well as the AI2 Privacy Policy covering Semantic Scholar.
OpenAlex data
Load additional information about publications from .
Privacy notice: By enabling the option above, your browser will contact the API of openalex.org to load additional information. Although we do not have any reason to believe that your call will be tracked, we do not have any control over how the remote server uses your data. So please proceed with care and consider checking the information given by OpenAlex.
last updated on 2025-02-08 00:50 CET by the dblp team
all metadata released as open data under CC0 1.0 license
see also: Terms of Use | Privacy Policy | Imprint