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The spatial and temporal pattern of rural settlements is the basis for optimizing land use and rational planning of rural areas, which is conducive to understanding the internal mechanism of changes of rural settlements and promoting the construction of new rural areas and rural revitalization. Based on the data of land use types in the coastal areas of Zhejiang Province from 1980 to 2020, this paper analyzes the changes of the scale and spatial pattern of rural settlements in the coastal areas of Zhejiang Province in the past 40 years by using the methods of single land use dynamic attitude, land use activity, landscape pattern index, nuclear density, standard deviation ellipse and geographical detector. The results show that: (1) From 1980 to 2020, the area of rural settlements in coastal areas of Zhejiang continues to increase by nearly 81%, and the area transferred out is less than the area transferred in. The area transferred in is mainly cultivated land and forest land, and the activity fluctuates greatly. (2) From 1980 to 2020, the size of rural settlements showed a fluctuating growth trend, with a growth rate of 335.90%, and the patch morphology index showed a slight increase in complexity, showing a clustering trend. (3) Rural settlements are concentrated in Jiaxing City, Hangzhou City and other coastal plain areas, the degree of agglomeration gradually weakens from north to south, and the southeast direction is the expansion hotspot. (4) The analysis of geographical detectors showed that elevation and slope contributed the most to spatial distribution, while precipitation, distance from rivers and GDP density had a higher impact. Therefore, attention should be paid to the role of natural factors in rural planning. This study can provide important reference for rural planning and development, guide the rational distribution of rural construction and resource utilization, provide scientific basis for the government to formulate rural development policies, resource allocation and management, and promote the implementation of rural revitalization strategy. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Automobile Technology & Material is the property of Automobile Technology & Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Jilin University (Medicine Edition) is the property of Jilin University Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Bio-oss bone powder and Aobang repair materials are commonly used bone repair materials, but there are few reports on their systematic evaluation of the repair effect of rabbit femoral defect. OBJECTIVE: To systematically evaluate the repair effects of Bio-oss bone powder and Aobang repair materials on femoral defects by using synchrotronradiation-based micro-computed tomography and histopathological staining. METHODS: Thirty-two rabbits were randomly divided into the control group (n=12) and the experimental group (n=20) by the random number table method. Two holes with a size of 4 mm (the diameter of the cavity) × 6 mm (hole depth) of penetrating periosteal bone defect were established on the lateral surface of one side of the femoral body. The control group was filled with normal saline. In the experimental group, Bio-oss bone powder was implanted in one of the bone defects, and Aobang repair material was implanted in the other bone defect. After 8 weeks, the effects of the two kinds of bone repair materials were evaluated by visual observation, imaging analysis and histopathological examination. RESULTS AND CONCLUSION: (1) General view: 8 weeks after the operation, the wounds in the repaired area of bone injury in the experimental group healed well; no infection, suppuration or other symptoms were found, and the animal mobility was significantly better than that of the control group. (2) Imaging examination: synchrotron-radiation-based micro-computed tomography 8 weeks after the operation exhibited that after the implantation of Bio-oss bone powder, there was a large amount of new bone tissue around the bone powder, and the cavity of the bone defect was large, which was not completely filled by the new bone tissue. After the implantation of the Aobang repair material, a large amount of new bone tissue at the bone defect cavity was formed around the repair material. 3D reconstruction showed that both bone filling materials could contact with local bone wound tissue, promote the surrounding osteogenesis to differentiate into new bone tissue and blood vessel formation, and achieve bone repair effect. The new bone around the Aobang repair material was more closely connected with the surrounding bone tissue. 256 iCT scan showed that the CT value of the Aobang repair material side at 8 weeks after operation was higher than that of the Bio-oss bone powder side (P < 0.05). (3) Histopathology: At 8 weeks after operation, hematoxylin-eosin staining showed that new bone tissue could be seen around the side of the Bio-oss bone powder. Bone tissue formed by bone matrix could be seen around the Aobang repair material; the new bone tissue was complete and coherent, and some of the new bone had invaded into the Aobang repair material. (4) These results suggest that Aobang repair material can promote the formation of new bone and damage repair; synchrotron-radiation-based micro-computed tomography echoes the traditional hematoxylin-eosin staining, and it is a good method to evaluate the effect of bone powder repair. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to explore the complex thermal characteristics of five-axis NC (numerical control) machine tools, a method for thermal error modeling of cradle five-axis NC machine tools was proposed. The principle of shark smell optimization (SSO) algorithm and neural network composite modeling was adopted, which effectively improved the accuracy and modeling efficiency of the machine tool thermal error prediction model. Firstly, the temperature sensitive point was screened by using the thermal imager, and then the temperature sensor was placed at the position of the heat sensitive point of the machine tool. The collected thermal characteristic data were modeled by the above method. The results showed that the method is better than ABC neural network and PSO neural network in terms of modeling speed and accuracy. Finally, the model was applied to the thermal error compensation experiment of the five-axis machine tool, which improves its accuracy by 32%. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin University of Science & Technology is the property of Journal of Harbin University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mechanical & Electronic Control Engineering is the property of Omniscient Pte. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Two-dimensional transition metal carbon/nitride (MXene) has a graphene-like structure, and microscopically exhibits lamellar and various surface groups. It has good electrical conductivity, ion transport and high hydrophilic properties, and becomes ideal electrode material for supercapacitor. The MXene layer and layer, which are prone to collapse and stacking, and the presence of functional groups are detrimental to the performance as an electrode material. It would have great application prospects, if its electrochemical performance could be improved by heat treatment, ion intercalation and carbon composites. In this paper, the preparation methods of MXene materials were firstly introduced, and then the effects of surface modification and structure optimization on the electrochemical performance of MXene supercapacitors were summarized. Finally, the research prospects of MXene materials on supercapacitors were prospected. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Henan University of Technology Natural Science Edition is the property of Henan University of Technology Journal Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Natural Resources / Ziran Ziyuan Xuebao is the property of Journal of Natural Resources and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: With a clear distinction from traditional computed tomography (CT) imaging with information absorption, phase-contrast CT with synchronous radiation has implemented the microstructure imaging of soft tissues in organisms with an unprecedented imaging mechanism. OBJECTIVE: To explore the synchrotron radiation phase-contrast CT imaging technology in the bone regeneration imaging after bone grafting. METHODS: Four New Zealand white rabbits were used to make a metaphyseal defect model. Then, model rabbits were randomized into a group with calcium phosphate bone grafting and a group with Bio-Oss bone grafting in the defects. The specimens were imaged by the synchrotron radiation phase-contrast CT and stained with hematoxylin-eosin and sirius red 2 weeks after bone grafting. RESULTS AND CONCLUSION: (1) Bio-Oss bone graft material group: Osteoid was observed not only around the graft material but also in the area far from the graft bone material as reticulate structure by the synchrotron radiation phase-contrast CT. Hematoxylin-eosin staining showed a large amount of red osteoid tissues arranged as trabecular bone, and a large amount of osteoblasts with obvious osteogensis. Sirius red-stained pathological sections were largely stained yellow, and there were round or oval osteoblasts with strongly expressed type I collagen. (2) Calcium phosphate bone graft material group: There was no reticulate structure shown by the synchrotron radiation phase-contrast CT, and the creep of osteoid tissues was only around the bone graft. Hematoxylin-eosin staining showed a large amount of red osteoid tissues, and sirius red-stained pathological sections were stained yellow and red. To conclude, the synchronous radiation phase- contrast CT can clearly display the regenerated structure of bone grafts. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of Beijing Institute of Technology is the property of Beijing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to meet the requirements of quadruped robots' leg structure with high cushion performance in running movements， a leg structure of running quadruped robots was designed， which was based on the bone-muscle biomechanical properties of dog forelegs. The leg structure has three joints and three DOFs. The hip joint and knee joint have active pitching-DOF， and the ankle joint has passive pitching-DOF. The dynamics and stiffness characteristics of the leg structure were analyzed， and the simulation of bound gait was done. The simulation results showed that a quadruped robot with this leg structure can run rapidly and stably while the joint drive torque is low. It was proven that this leg structure has the feasibility and rationality of making quadruped robots run in bound gait. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Northeastern University (Natural Science) is the property of Dongbei Daxue Xuebao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)