18,956 research outputs found
Vector-based model predictive hysteresis current control for asynchronous motor
No full textModel predictive control, especially model predictive current control, has received a great deal of attention in the motor drive field in recent years, due to its ability to render fast dynamic response and to handle multiple variables, nonlinearities, and system constraints in an intuitive way. However, the conventional single-vector-based model predictive hysteresis current control (SV-MPHCC) brings about some problems, such as high sampling frequency and poor steady-state control performance. In this paper' a novel double-vector-based model predictive hysteresis current control (DV-MPHCC), which utilizes an arbitrary vector and a zero vector to form a voltage vector combination, is proposed. To verify the improved performance over a short predictive horizon, a series of comparisons are conducted between the two control algorithms by simulation and experiment in the paper. Both simulation and experiment results validate that the DV-MPHCC proposed has advanced steady-state control performance, and a lower sampling frequency.</p
Source code and demo of MAGUS (Machine Learning and Graph Theory Assisted Universal Structure Searcher) v2.0.0
No full textThis is the source code and demo for MAGUS (Machine Learning and Graph Theory Assisted Universal Structure Searcher) v2.0.0. Future updates can be accessed from gitlab (https://gitlab.com/bigd4/magus) after registration (https://www.wjx.top/vm/m5eWS0X.aspx).MAGUS is a Python package designed to predict crystal structures, which is free for non-commercial academic use, subject to registration and approval at https://www.wjx.top/vm/m5eWS0X.aspx .
1) This Code or its derivative work will not be used for any purpose other than non-commercial research.
2) This Code or its derivative code will not be published or otherwise distributed.
3) The use of this Code should be acknowledged by citing the tutorial paper describing the use of this code:
[1] Junjie Wang, Hao Gao, Yu Han, Chi Ding, Shuning Pan, Yong Wang, Qiuhan Jia, Hui-Tian Wang, Dingyu Xing, and Jian Sun, "MAGUS: machine learning and graph theory assisted universal structure searcher", National Science Review 10 (7), nwad128 (2023).
[2] Kang Xia, Hao Gao, Cong Liu, Jianan Yuan, Jian Sun, Hui-Tian Wang, Dingyu Xing, "A novel superhard tungsten nitride predicted by machine-learning accelerated crystal structure search", Sci. Bull. 63, 817 (2018).Additional references that may be cited (at the discretion of the user) are:
Graph theory:
[3] Hao Gao, Junjie Wang, Yu Han, Jian Sun, "Enhancing Crystal Structure Prediction by Decomposition and Evolution Schemes Based on Graph Theory", Fundamental Research 1, 466 (2021).
[4] Hao Gao, Junjie Wang, Zhaopeng Guo, Jian Sun, "Determining dimensionalities and multiplicities of crystal nets" npj Comput. Mater. 6, 143 (2020).
Surface reconstruction:
[5] Y. Han, J. Wang, C. Ding, H. Gao, S. Pan, Q. Jia, and J. Sun, "Prediction of surface reconstructions using MAGUS", The Journal of Chemical Physics 158 (17), 174109 (2023).
Structure searching in confined space:
[6] Chi Ding, Junjie Wang, Yu Han, Jianan Yuan, Hao Gao, and Jian Sun, "High Energy Density Polymeric Nitrogen Nanotubes inside Carbon Nanotubes", Chin. Phys. Lett. 39, 036101 (2022). (Express Letter)Peer reviewe
Dataset to support the article "High-resolution 𝜙-OFDR using phase unwrap and nonlinearity suppression"
No full textThis dataset is used for realizing high resolution of phase-sensitive Optical Frequency Domain Reflectometer. It is associated with the research paper:
Guo Z, Yan J, Han G, Yu Y, Greenwood D and Marco J (2023) "High-Resolution φ-OFDR Using Phase Unwrap and Nonlinearity Suppression". Journal of Lightwave Technology, 41 (9), 2885-2891. (https://doi.org/10.1109/JLT.2023.3236775).
The data is presented as an excel file:
High_resolution_OFDR_using_phase_unwrap_and_nonlinearity_suppression.xlsx
This work was funded by High Value Manufacturing Catapult and the Engineer and Physical Sciences Research Council - EPSRC EP/V000624/1. The author Gaoce Han would like to acknowledge the China Scholarship Council for sponsoring.</span
Han Suyin (Chinese author) speaking at Dallas Brookes Hall.
No full textThis record was harvested from a previous catalogue system and will be withdrawn in 2025. Information in this record may be superseded or incomplete. Visit this record in UMA's new catalogue at: https://archives.library.unimelb.edu.au/nodes/view/276390Han Suyin (Chinese author) speaking at Dallas Brookes Hall.200056
Item: [1999.0081.00439] "Han Suyin (Chinese author) speaking at Dallas Brookes Hall.
A Study on the mathematics textbooks in the era of the Great Han Empire
No full text이 글은 갑오경장(1894)과 경술 국치(1910) 사이에 간행된 산학(수학) 교재류의 목록을 확인하고, 각 텍스트의 출판과 관련된 사항, 소장처, 이본 등의 서지적 정보와 함께 이 시기 산학 교재류의 국어사 자료로서의 의의를 언어 사용 상의 측면에 초점을 두어 정리하는 것을 목적으로 한다. 이는 현대 한국어 태동기의 분과 학문의 도입 양상에 대한 연구의 일환인 한편, 학술 용어의 번역과 정착을 중심으로 이 시기의 한국어의 어휘 확장 양상을 확인하는 데에 필요한 기초 자료를 정리하는 작업의 한 부분이다. 본 연구에 앞선 산학(수학) 교재류에 대한 연구로는 산학 교재류의 서지 사항에 대해 기술한 강윤호(1973:187-199), 김봉희(1992:247-253), 한길준(2009), 오채환 외(2010) 등이 있고, 한국 수학사를 기술하면서 교재류를 함께 다룬 것으로 김용운·김용국(1982)와 이상구(2013)이 있다.This paper aims to make a whole list of the mathematics textbooks in the era of the Great Han Empire and summerize bibliographical data and linguistic characteristics in view of Korean history. In chapter 1, the author reviewed former studies which deals with the mathematics textbooks in the era of the Great Han Empire. In chapter 2, the author summerized bibliographical data of 45 volumes of 32 kinds textbooks. In chapter 3, the author described linguistic characteristics of the textbooks, especially focusing on writing systems, the use of Arabic numerals, horizontal writing, and presence of index or glossary
Also By The Same Author: AKTiveAuthor, a Citation Graph Approach to Name Disambiguation
No full textThe desire for definitive data and the semantic web drive for inference over heterogeneous data sources requires co-reference resolution to be performed on those data. In particular, name disambiguation is required to allow accurate publication lists, citation counts and impact measures to be determined. This paper describes a graph-based approach to author disambiguation on large-scale citation networks. Using self-citation, co-authorship and document source analyses, AKTiveAuthor clusters papers, achieving precision of 0.997 and recall of 0.818 over a test group of eight surname clusters
Data supporting "A generalized method for refining and selecting random crystal structures using graph theory"
No full textThe dataset contains all the structure files of the nine test systems in CIF and XYZ format. In each system folder, there are 12 folders (excluding C48):
SBG-baseline: the initial structures
QGBR_init: initial structures selected by QGBR
QGBR: QGBR refined structrues discard: initial structures discarded by QGBR
QGBR-B_init: initial structures selected by QGBR-B
QGBR-B: QGBR-B refined structrues discard-b: initial structures discarded by QGBR-B refinement
and their corresponding relaxed structures with "_relaxed" as the suffix.
In each "_relaxed" folder in CIF format, there is an "energy.txt" that contains the energy (enthalpy) of the relaxed structures.
Note that there are a few rare cases where the relaxation structure configuration is physically unreasonable but the energy (enthalpy) is lower than that of the ground state structure. These structures are not taken into account in our study.Peer reviewe
Dataset to support the article "High Sensing Accuracy Realisation with Millimetre/sub-Millimetre Resolution in Optical Frequency Domain Reflectometer"
No full textThis dataset is used for realizing high sensing accuracy and sub-millimetre resolution of Optical Frequency Domain Reflectometer. It is associated with the research paper "High Sensing Accuracy Realisation with Millimetre sub-Millimetre Resolution in Optical Frequency Domain Reflectometer" in Journal: Journal of Lightwave Technology.
This work was funded by High Value Manufacturing Catapult, grant reference, 160080 CORE (WMG), titled ‘Smart Sensing for Future Batteries’ and the EPSRC (Engineering and Physical Sciences Research Council), grant reference EP/R004927/1, titled ‘Prosperity Partnership’. The author Gaoce Han would like to acknowledge the China Scholarship Council for sponsoring.</span
Bidirectional variable probability RRT algorithm for robotic path planning
No full textThe traditional goal-bias RRT is mentioned to improve the efficiency, but it has an inherent problem, when there are lesser vertexes, the search toward the goal is often invalid; however, when there are more vertexes, the search toward other regions is often unnecessary. To solve this problem, we introduce a kind bidirectional variable probability RRT algorithm. In this paper, we build two trees, and one tree expands toward to the other tree at a variable probability. This probability is in proportion to the coverage of the trees, that is, when there are lesser vertexes, the searches are mainly toward unexplored regions, and when there are more vertexes, we attach more importance to the connection of two trees. The results show the good performance and convergence speed of the proposed algorithm
Thermoelectric polymer-cellulose composite aerogels
No full textThermoelectric materials are scrutinized as energy materials and sensing materials. Indeed, they convert thermal energy into electrical energy. In addition, those materials are actively sensitive to a temperature modification through the generation of an electric signal. Organic thermoelectric (OTE) materials are complementary to inorganic thermoelectric materials, as they possess unique properties such as solution processing, ionic conductivity, flexibility, and softness. While thin-film OTE materials have been widely studied because they are easily manufactured by various coating techniques, little is done in the creation of three-dimensional morphologies of OTE materials; which is important to develop large temperature gradients. Cellulose is the most abundant biopolymer on the planet. Recently, the applications of cellulose are not only limited in making papers but also in electronics as the cellulose provide 3-D microstructures and mechanical strength. One promising approach to make 3-D OTE bulks is using cellulose as scaffold because of their properties of relatively high mechanical strength, water processability and environmentally friendly performance. The aims of the thesis have been to enlarge the applications of an OTE material poly(3,4-ethylenedioxythiophene) (PEDOT), with an approach of making 3-D aerogels composite with nanofibrillated cellulose (NFC), in two main areas: (1) multi-parameter sensors and (2) solar vapor generators. In the first application, we demonstrate that the new thermoelectric aerogel responds independently to pressure P, temperature T and humidity RH. Hence, when it is submitted to the three stresses (T, P, RH), the electrical characterization of the material enables to measure the three parameters without cross-talking effects. Thermoelectric aerogels are foreseen as active materials in electronic skins and robotics. In the second application, the conducting polymer aerogels are employed as solar absorbers to convert solar energy into heat and significantly increased the water evaporation rate. The IR absorption is efficient because of the free-electron in the conducting polymer PEDOT nano-aggregates. Because of the low cost of those materials and the water stability of the crosslinked aerogels, they could be of importance for water desalination.Termoelektriska material har utvärderats som energi- och sensormaterial. Som energimaterial har de studerats som ett sätt att transformera termisk energi till elektrisk energi, och har använts för kylnings- och uppvärmningsapplikationer. Som sensormaterial kan de känna av temperatur eller temperaturskillnader och tillhandahåller elektriska signaler. Organiska termoelektriska (OTE) material, det vill säga kolbaserade termoelektriska material, är komplementära till inorganiska termoelektriska material eftersom de har unika egenskaper så som processbarhet i lösningsform, jonisk ledningsförmåga, böjbarhet, och mjukhet. Tunna filmer av OTE-material har vida studerats eftersom de är lätta att tillverka via olika beläggningsmetoder, men tredimensionella strukturer är till stor del ett outforskat område och är viktigt för att uppnå stora temperaturgradienter. Cellulosa är ett billigt material som utgör den vanligaste biopolymeren på vår planet. Nyligen så har applikationerna för cellulosa sträckt sig bortom papperstillverkning och används nu även inom elektronik för att förse 3D-mikrostrukturer och mekanisk styrka. En lovande metod för att tillverka 3D-strukturer av OTE-material är genom att använda cellulosanätverk på grund av dess relativt höga mekaniska styrka, processbarhet i vattenlösningar och dess miljövänlighet. Syftet med denna avhandling har varit att bredda applikationerna för OTE-materialet poly(3,4-ethylenedioxythiophene) (PEDOT), genom att tillverka 3D aerogelkompositer med nanofibrillerad cellulosa (NFC). Detta har gjorts inom två områden: (1) Multiparameter-sensorer och (2) solar vapor generators. För den första applikationen så demonstrerar vi att de nya termoelektriska aerogelerna har oberoende signaler från tryck, temperatur och relativ fuktighet. Det vill säga att när materialet utsätts för dessa stimuli så kan signalerna som genereras urskiljas av utan överhörning. De termoelektriska aerogelena förutses bli användbara inom områden så som elektronisk hud och robotik. För den andra applikationen används de elektriskt ledande aerogelena för att absorbera solljus för att omvandla solenergi till värme vilket kan öka förångningshastigheten hos vatten. Absorptionen i IR-området är effektivt eftersom de rörliga elektronerna i den ledande polymeren nano-aggregerar. På grund av den låga kostnaden hos dessa material och våtstabiliteten hos korslänkade aerogeler kan dessa material tänkas användas för vattenavsaltning
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