المؤلفون: Qiyue Xie, Yixing Xiao, Xiaoli Wang, Daifei Liu, Zhongli Shen

المصدر: IEEE Access, Vol 7, Pp 135031-135039 (2019)

مصطلحات موضوعية: Solar tower power plant, heliostat tracking, cluster control, leader-follower strategy, Electrical engineering. Electronics. Nuclear engineering, TK1-9971

الوصف: As one of the most promising power generation technologies using renewable energy sources, and the solar thermal electric power generation may be developed to alleviate the energy crisis. But it still faces the obstacles of excessive cost and low energy efficiency nowadays. To this end, a method of using heliostats cluster control is proposed to solve the main contradiction in solar tower power plants. In this approach, the entire heliostats field will be divided into a few groups, and a leader heliostat with high-precision closed-loop control is arranged in each group while the remaining heliostats as follower heliostats. On this basis, a leader heliostat tracking model is established and a leader-to-follower heliostat conversion mode is designed. Meanwhile, the posture information of adjacent leader heliostats is communicated to guarantee the tracking reliability. According to the simulation results of this paper, this method not only improves the automation level of solar tower power plants at this stage, but also reduces the computing complexity of the heliostats field control algorithm. Moreover, the proposed method improves the precision of the control, and also reduces the control cost, making the closed-loop control of the heliostats field possible.

وصف الملف: electronic resource

العلاقة: https://ieeexplore.ieee.org/document/8830390Test/; https://doaj.org/toc/2169-3536Test

الوصول الحر: https://doaj.org/article/0109657f29d64200b31868ad634e1097Test

المؤلفون: Qiyue Xie, Caifengyao Zhong, Daifei Liu, Qiang Fu, Xiaoli Wang, Zhongli Shen

المصدر: Energies, Vol 13, Iss 20, p 5247 (2020)

مصطلحات موضوعية: SAG mill, DEM, mill power, mill speed, steel ball ratio, fill level, Technology

الوصف: As one of the machines widely used in mining, a semi-autogenous grinding (SAG) mill can significantly improve the roughing efficiency of rock. But the SAG mill still faces the obstacles of significant energy consumption and empirical operation parameters. In order to obtain the optimal operation parameters of a SAG mill, in this paper, the discrete element method (DEM) is used to simulate the breakage process of the particles by controlling three parameters, i.e., the mill speed ratio, the mill fill level ratio, and the steel ball ratio. This method simulates the particles size, mill power, and qualified particles quality of crushed particle, which reveal the grinding strength and energy consumption of the SAG mill. In this paper, the grinding changes of a SAG mill under different parameter conditions are explored. Firstly, an experiment on the influence of a single parameter change on the mill’s operation is set up, and then the influence of three parameter changes on the mill’s operation is analyzed. These changes are characterized by particle size and mill power. Simulation results under the ∅5250 × 500 mm mill model show that the mill operates with the optimal effect when the mill is under the condition of 80% critical speed and 15% fill level; the power of the mill does not increase linearly with an increase in the mill speed ratio, but will decrease after 85% of the critical speed, and finally increase again; the optimal steel ball ratio in the SAG mill depends on the simulation time (mill actual working time) and the limitation of the rated power. The mill speed, fill level ratio, and steel ball ratio can significantly affect mill operation, and our conclusions can provide a reference for an actual situation.

وصف الملف: electronic resource

العلاقة: https://www.mdpi.com/1996-1073/13/20/5247Test; https://doaj.org/toc/1996-1073Test

الوصول الحر: https://doaj.org/article/68e86a661f6443cfa20e83c72c07bfb3Test

المؤلفون: Daifei Liu, Xueqi Liu, Zhiguo Shang, Charles V Sindelar

المصدر: eLife, Vol 6 (2017)

مصطلحات موضوعية: Kinesin, Motor protein, ATPase, Microtubule, Cytoskeletal motors, Medicine, Science, Biology (General), QH301-705.5

الوصف: The detailed basis of walking by dimeric molecules of kinesin along microtubules has remained unclear, partly because available structural methods have been unable to capture microtubule-bound intermediates of this process. Utilizing novel electron cryomicroscopy methods, we solved structures of microtubule-attached, dimeric kinesin bound to an ATP analog. We find that under these conditions, the kinesin dimer can attach to the microtubule with either one or two motor domains, and we present sub-nanometer resolution reconstructions of both states. The former structure reveals a novel kinesin conformation that revises the current understanding of how ATP binding is coupled to forward stepping of the motor. The latter structure indicates how tension between the two motor domains keeps their cycles out of phase in order to stimulate directional motility. The methods presented here pave the way for future structural studies of a variety of challenging macromolecules that bind to microtubules and other filaments.

وصف الملف: electronic resource

العلاقة: https://elifesciences.org/articles/24490Test; https://doaj.org/toc/2050-084XTest

الوصول الحر: https://doaj.org/article/5abe363fdad3401e8713212df9c9c6ddTest

المؤلفون: Qiyue Xie, Xiaoli Wang, Chen Zhisheng, Ziqi Guo, Zhongli Shen, Daifei Liu

المصدر: Renewable Energy. 176:447-458

مصطلحات موضوعية: Heliostat, 060102 archaeology, Field (physics), Power station, Renewable Energy, Sustainability and the Environment, Computer science, business.industry, 020209 energy, Attenuation, Thermal power station, 06 humanities and the arts, 02 engineering and technology, Software, Control theory, Electromagnetic shielding, Convergence (routing), 0202 electrical engineering, electronic engineering, information engineering, 0601 history and archaeology, business

الوصف: The heliostat field of tower solar thermal power station accounts for 40%–50% of the total cost, and influences the concentrating efficiency. Accordingly, it is necessary to optimize the layout of the heliostat field. Based on the optical efficiency model, an improved Gray Wolf Optimization (GWO) algorithm is proposed to optimize the field parameters of the heliostats, improve the convergence factor and weight updating formula, and effectively avoid the local optimal problem. Then SolarPILOT software is used to simulate the heliostat field distribution. In order to reduce the shadow and shielding efficiency loss, improve the land utilization rate and atmospheric attenuation efficiency, the heliostat field is initialized by radial staggered arrangement, which is easy to be optimized. By using the optical efficiency model, the program of heliostat field optimization algorithm is developed, and a Delingha tower power station is used to verify the algorithm. After the improved GWO algorithm optimizing the heliostat field, the optical or concentrating efficiency of the heliostat field is increased by 8.2% compared with the GWO algorithm. The improved GWO algorithm reduces the heliostat number by 3.4% compared with the Gray Wolf algorithm, and that reducing the cost of the heliostat field.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::eb136e9d3616e88c894669f77bc16814Test
https://doi.org/10.1016/j.renene.2021.05.058Test

المؤلفون: Xiaoming Zhou, Lily Sumrow, Kyuto Tashiro, Lillian Sutherland, Daifei Liu, Tian Qin, Masato Kato, Glen Liszczak, Steven L. McKnight

المصدر: Science

مصطلحات موضوعية: DNA-Binding Proteins, Protein Folding, Multidisciplinary, Protein Domains, Alzheimer Disease, Charcot-Marie-Tooth Disease, Protein Stability, Frontotemporal Dementia, Mutation, Missense, Humans, Cells, Cultured, Article

الوصف: Protein domains of low sequence complexity do not fold into stable, three-dimensional structures. Nevertheless, proteins with these sequences assist in many aspects of cell organization, including assembly of nuclear and cytoplasmic structures not surrounded by membranes. The dynamic nature of these cellular assemblies is caused by the ability of low-complexity domains (LCDs) to transiently self-associate through labile, cross-β structures. Mechanistic studies useful for the study of LCD self-association have evolved over the past decade in the form of simple assays of phase separation. Here, we have used such assays to demonstrate that the interactions responsible for LCD self-association can be dictated by labile protein structures poised close to equilibrium between the folded and unfolded states. Furthermore, missense mutations causing Charcot-Marie-Tooth disease, frontotemporal dementia, and Alzheimer’s disease manifest their pathophysiology in vitro and in cultured cell systems by enhancing the stability of otherwise labile molecular structures formed upon LCD self-association.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::a8afce5ac3de7d9dcb55e1df651f38edTest
https://doi.org/10.1126/science.abn5582Test

المؤلفون: Youfu Lv, Weiming Luo, Chuanchang Li, Daifei Liu, Jian Chen, Yijie Zhuang, Weixiong Wu

المصدر: Applied Thermal Engineering. 221:119840

مصطلحات موضوعية: Energy Engineering and Power Technology, Industrial and Manufacturing Engineering

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::07931953d0ec7feb1ffb53c0d06498f0Test
https://doi.org/10.1016/j.applthermaleng.2022.119840Test

المؤلفون: Sina Ghaemmaghami, Benjamin P. Tu, Masato Kato, Yi Lin, Xiaoming Zhou, Daifei Liu, Steven L. McKnight

المصدر: Proceedings of the National Academy of Sciences of the United States of America

مصطلحات موضوعية: TDP-43, medicine.disease_cause, Biochemistry, Polymerization, chemistry.chemical_compound, low-complexity sequence, Protein Domains, medicine, Humans, Amino Acid Sequence, Conserved Sequence, Ataxin-2, chemistry.chemical_classification, Mutation, Multidisciplinary, Methionine, Translation (biology), cross-beta polymers, Biological Sciences, Footprinting, redox sensor, DNA-Binding Proteins, Enzyme, HEK293 Cells, chemistry, neurodegenerative disorders, Self-healing hydrogels, Biophysics, Methionine sulfoxide reductase, Reactive Oxygen Species

الوصف: Significance The TDP43 RNA binding protein is frequently aggregated in the brain tissue of patients suffering from neurodegenerative diseases. Human genetic studies of patients suffering from ALS have identified scores of missense mutations clustered within a localized region of the TDP43 protein. This region is of low sequence complexity and has been thought to exist in a state of structural disorder under conditions of proper TDP43 function. The present study gives evidence that the low complexity domain of TDP43 self-associates into a specific structural conformation that may be important to its normal biological function. Unlike prototypic low complexity domains, that of TDP43 is methionine-rich. Evidence is presented suggestive of the utility of these methionine residues in oxidation-mediated regulation of TDP43 function.
A methionine-rich low complexity (LC) domain is found within a C-terminal region of the TDP43 RNA-binding protein. Self-association of this domain leads to the formation of labile cross-β polymers and liquid-like droplets. Treatment with H2O2 caused phenomena of methionine oxidation and droplet melting that were reversed upon exposure of the oxidized protein to methionine sulfoxide reductase enzymes. Morphological features of the cross-β polymers were revealed by H2O2-mediated footprinting. Equivalent TDP43 LC domain footprints were observed in polymerized hydrogels, liquid-like droplets, and living cells. The ability of H2O2 to impede cross-β polymerization was abrogated by the prominent M337V amyotrophic lateral sclerosis-causing mutation. These observations may offer insight into the biological role of TDP43 in facilitating synapse-localized translation as well as aberrant aggregation of the protein in neurodegenerative diseases.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::e0d5c3965b20fd36931728f1b3335106Test
http://europepmc.org/articles/PMC7682574Test

المؤلفون: Lei Tan, Qiaoyun Chen, Peng Chen, Xing Huang, Lingjun Li, Kangyu Zou, Daifei Liu

المصدر: Journal of Electroanalytical Chemistry. 928:117063

مصطلحات موضوعية: General Chemical Engineering, Electrochemistry, Analytical Chemistry

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::895f8f9ae0d2a173b8d8be561fed6561Test
https://doi.org/10.1016/j.jelechem.2022.117063Test

المؤلفون: Jin Liu, Sheng He, Yiting Tao, Daifei Liu

المصدر: IEEE Sensors Journal. 20:11812-11819

مصطلحات موضوعية: Artificial neural network, Computer science, business.industry, 010401 analytical chemistry, Normalization (image processing), Rotation matrix, Frame rate, 01 natural sciences, Convolutional neural network, 0104 chemical sciences, Minimum bounding box, Computer vision, Artificial intelligence, Electrical and Electronic Engineering, Quaternion, business, Instrumentation, Dykstra's projection algorithm

الوصف: We present a new approach to efficiently detect the 3D pose of objects in images. The approach uses a single neural network we call TQ-Net to predict the translation vector and the quaternion, after which the quaternion is converted to a rotation matrix, and through a projection algorithm, we can project eight points surrounding the object to the image and connect them to form a 3D bounding box. Considering there is a constraint existing in the quaternion, we add a normalization layer to get a more precise result. Experiments show that our approach performs well and can detect 3D poses in real time. Our approach processes images with a resolution of 1280*720 at 61 frames per second on a GTX 1080 GPU.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::1a58e6edb89adfad4306f5d4e5f8b715Test
https://doi.org/10.1109/jsen.2019.2946279Test

المؤلفون: Xiaoming Zhou, Lily Sumrow, Lillian Sutherland, Daifei Liu, Tian Qin, Steven L. McKnight, Glen Liszczak

الوصف: TAR binding protein 43 (TDP-43) is an RNA binding protein that assists in the maturation, export and sub-cellular localization of mRNA. The carboxyl terminal 153 residues of TDP-43 are of low sequence complexity and allow for self-association of the protein in a manner leading to its phase separation from an aqueous environment. These interactions assist TDP-43 in forming cytoplasmic RNA granules involved in the transport of mRNA for localized translation. Self-association of the TDP-43 low complexity (LC) domain is facilitated by a region of twenty five residues that are of extreme evolutionary conservation. The molecular basis for self-adherence of the protein through this region has been illuminated by a combination of structural and biochemical studies, allowing definition of a morphologically specific cross-β structure predicted to be weakly assembled by main chain hydrogen bonds. In this study we have investigated the importance of individual, Pauling hydrogen bonds hypothesized to facilitate self-adherence of the TDP-43 LC domain.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::b0374dc3c729a5c844e72083f27e36e1Test
https://doi.org/10.1101/2021.12.05.471332Test