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Comparative Study on Changes of Croplands Between North Korea and South Korea During 1990–2015

Chinese geographical Science 2018年第6期28卷 920-934页

作者： YU hao zHANg Bai WANg zongming Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changch un 130102 China University of Chinese Academy of Sciences Beijing 100049 China

Studies on long-term change of cropland is of great significance to the utilization of land resources and the implementation of scientific agricultural policies. The Korean Peninsula, adjacent to China, plays an important role in the international environment of Northeast Asia. The Korean Peninsula includes South Korea and North Korea—two countries that have a great difference in their institutions and economic developments. Therefore, we aim to quantify the spatiotemporal changes of croplands in these two countries using Landsat Thematic Imager(TM) and Operational Land Imager(OLI) imagery, and to compare the differences of cropland changes between the two countries. This paper take full advantage of ODM approach(object-oriented segmentation and decision-tree classification based on multi-season imageries) to obtain the distribution of croplands in 1990 and 2015. Results showed that the overall classification accuracy of cropland data is 91.10% in 1990 and 92.52% in 2015. The croplands were mainly distributed in areas with slopes that were less than 8° and with elevations that were less than 300 m in the Korean Peninsula. However, in other region(slope > 8° or elevation > 300 m), the area and proportion of North Korea's croplands were significantly higher than that of South Korea. Croplands significantly increased by 15.02% in North Korea from 1990 to 2015. In contrast, croplands in South Korea slightly decreased by 1.32%. During the 25 years, policy shift, economic development, population growth, and urban sprawl played primary roles for cropland changes. Additionally, the regional differences of cropland changes were mainly due to different agriculture policies implemented by different countries. The achievements of this study can provide scientific guidance for the protection and sustainability of land resources.

关键词： Landsat object-oriented segmentation decision tree cropland North Korea South Korea

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High energy storage capability of perovskite relaxor ferroelectrics via hierarchical optimization

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Rare Metals 2022年第3期41卷 730-744页

作者： Min-hao zhang Jun-Lei Qi Yi-Qian Liu Shun Lan zi-Xi Luo hao Pan Yuan-Hua Lin State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Innovation Team for New High Volumetric Efﬁcient MLCC Materials and Devices Foshan(Southern China)Institute for New MaterialsFoshan 528000China Division of Physics and Applied Physics School of Physical and Mathematical SciencesNanyang Technological UniversitySingapore 639798Singapore

Ultrafast charge/discharge process and ultrahigh power density enable dielectrics essential components in modern electrical and electronic devices, especially in pulse power systems. However, in recent years, the energy storage performances of present dielectrics are increasingly unable to satisfy the growing demand for miniaturization and integration, which stimulates further researches on dielectrics with higher energy density and *** various inorganic dielectrics, perovskite relaxor ferroelectrics are recognized as promising candidates for energy storage applications, with high permittivity and relatively high efficiency. Here, we focus on recent progress and achievements on optimizing perovskite relaxor ferroelectrics toward better energy storage capability through hierarchical design. The principles and key parameters of dielectric energy storage, together with the definition of majority types of dielectrics, are introduced at first. Strategies within various scales include domain, grain size, orientation, and composite engineering are summarized. The existing challenges are presented and future prospects are proposed in the end, with the background of both academic explorations and industrial applications.

关键词： Dielectric Energy storage Capacitance Perovskite Relaxor ferroelectric

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Characterization of 4-Aryl-5-ethoxycarbonyl-6-methyl-3,4-dihydro-pyrimidin-2(1H)-thiones by EI-TOF Mass Spectrometry

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Chemical Research in Chinese Universities 2006年第1期22卷 40-44页

作者： LI Qian-rong XUE Song YIN hao Hefei National Laboratory for Physical Sciences at Microscale and Department of Chemistry University of Science and Technology of China Hefei 230026 P. R. China

The electron impact （EI） time-of-flight mass spectra （TOFMS） of the title compounds （ thioxo-Biginelli compounds） were studied to establish their fragmentation pathways. With a TOF instrument of high resolution, the exact mass for each fragment was determined. These data were used to infer the molecular formulas and the ionic elemental compositions for all the compounds through interpretation by software. By further applying chemical intuition, majority of the fragmentation ions were fully assigned. All the compounds give strong signals（ average 76% ） for their molecular ions in the El spectra. Two kinds of characteristic fragmentation pathways from the molecular ion were observed. One is related to the loss of the ester group, forming a resonance stabilized ion with a moderate abundance（ average 40% ）. The other concerns the loss of the aromatic-ring radical, forming another resonance stabilized ion at m/z 199 with a high abundance（ average 79% ）, from which further important fragmentations including the formation of an ion at m/z 171 （average 24% ） by the loss of C2H2 （via the McLafferty rearrangement）, and an ion at m/z 153（ average 10% ） by the elimination of a water molecule preceed. In addition, ion [ M - Et ]^＋ with a high abundance（average 62% ） is a characteristic for the Biginelli compounds with an ethoxycarbonyl group. Differences and similarities among the fragmentations observed from the EI-TOFMS of oxo-Biginelli compounds are discussed.

关键词： Beginelli compound 3,4-Dihydropyrimidinthione Time-of-flight mass spectrometry Electron impact

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A novel cylindrical sandwich plate inspired by beetle elytra and its compressive properties

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Science China(Technological Sciences) 2024年第11期67卷 3465-3476页

作者： SONg YiHeng RUAN SiHan hao Ning OKABE YoJi School of Engineering The University of TokyoTokyo 113-0033Japan School of Civil Engineering Southeast UniversityNanjing 211189China School of Engineering RMIT UniversityMelbourne 3001Australia Institute of Industrial Science The University of TokyoTokyo 153-8505Japan

The design and experimental analysis of a semi-cylindrical structure known as the cylindrical beetle elytron plate(CBEP)were *** compression tests and finite element simulation were performed on CBEPs under 30°and 45°inclined sliding support constraints,with a comparison made to cylindrical honeycomb plate(CHP).The study aims to investigate the superior compression performance and enhancement mechanisms of *** results demonstrate that CBEPs exhibit a 14%–26%increase in specific load-bearing capacity and a 20%increase in specific energy absorption compared with CHPs with equal core wall ***“z-shaped”tearing failures were observed,with honeycomb plates showing tearing at the center of the honeycomb walls,while beetle elytron plates exhibited tearing along the midline of the *** different stress patterns,including elastic-plastic development stage of arch,plastic hinge node stage,and rigid node stage,were identified and analyzed to explain the mechanical performance improvements and failure *** that structural damage to trabeculae mostly occurs at its junction with the skin,it is recommended to add chamfers to the junctions of ***,this paper lays the groundwork for the engineering application of CBEP.

关键词： beetle elytron cylindrical beetle elytron plate compression performance failure characteristics enhancement mechanism

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Enhanced Nonlinear Optical Properties of Laser Deposited Ag／BaTiO3 Nanocomposite Films

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Chinese Physics Letters 2003年第6期20卷 924-927页

作者： YANgguang WANgWei-Tian YANgguo-zhen CHENzheng-hao LaboratoryofOpticalPhysics InstituteofPhysicsandCenterforCondensedMatterPhysicsChineseAcademyofSciencesBeijing100080

The composite films containing Ag particles embedded in BaTiO3 matrix were deposited on MgO (100) substrates by using the pulsed laser deposition technique and characterized by x-ray diffraction and x-ray photoelectron spectroscopy. The absorption peak resulting from the surface plasmon resonance of Ag particles is found at the wavelength of 430 nm. The third-order nonlinear optical characteristics of the films are determined by z-scan technique using a nanosecond laser. The results show that the Ag/BaTiO3 nanocomposite films exhibit great optical nonlinearities and the real and imaginary parts of the third-order nonlinear susceptibility χ(3) are calculated to be 4.544×10-6 esu and 2.352×10-7 esu, respectively. The enhancement mechanism of χ(3) is discussed.

关键词： Nanocomposite films

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ON PAIRED PRIORITIzATIONS OF CRITERIA IN THE PERSPECTIVE OF DIAgRAPHS

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Journal of Systems Science and Systems Engineering 2015年第4期24卷 466-485页

作者： Wenning hao Xiaohan Yu zeshui Xu Xiuli Qi College of Command Information Systems PLA University of Science and Technology College of Sciences PLA University of Science and Technology

It is not usually independent among criteria in multi-criteria decision making(MCDM),and various dependences of criteria greatly influence the results of decision *** an exact decision is desired,we must make clear the role of the dependences of ***,a new kind of dependences of criteria proposed recently,imply that the importance weights of criteria with lower priority for an alternative rely on whether the alternative satisfies the decision maker under criteria with higher *** has been validated that there exist lots of relevant applications in our daily ***,most existing literatures focus on how to deal with the problems of MCDM with ordered prioritizations among criteria(a special form of prioritizations).The characteristics of prioritizations are not dug *** paper constructs a new form of prioritizations,called paired prioritizations,so as to reduce or even avoid imperfect rationality of decision makers hidden in the ordered *** first represent binary paired prioritizations as a digraph,based on which we discover two kinds of imperfect rationality(inconsistency and incompleteness) produced in the period that the decision maker supplies the binary paired *** the given paired prioritizations are consistent and complete,we develop an approach to transform the paired prioritizations to ordered *** latter can be used to handle prioritized MCDM ***,uncertainty,another kind of imperfect rationality,is considered when the decision maker provides the fuzzy paired prioritizations based on a set of linguistic *** construct a fuzzy digraph whose fuzzy relations are just the fuzzy paired *** ordered prioritizations can then be derived with the aid of the fuzzy *** use cases are taken to show the process of transformations from binary/fuzzy paired prioritizations to ordered prioritizations.

关键词： Paired prioritization ordered prioritization criteria digraph fuzzy digraph

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SELF-ORgANIzED SEMANTIC FEATURE EVOLUTION FOR AXIOMATIC DESIgN

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Chinese Journal of Mechanical Engineering 2008年第2期21卷 108-113页

作者： hao He FENg Yixiong TAN Jianrong XUE Yang State Key Laboratory of CAD ＆ Cg Zhejiang University Hangzhou 310027 China

Aiming at the problem existing in the computer aided design process that how to express the design intents with high-level engineering terminologies, a mechanical product self-organized semantic feature evolution technology for axiomatic design is proposed, so that the constraint relations between mechanical parts could be expressed in a semantic form which is more suitable for designers. By describing the evolution rules for semantic constraint information, the abstract expression of design semantics in mechanical product evolution process is realized and the constraint relations between parts are mapped to the geometric level from the semantic level; With semantic feature relation graph, the abstract semantic description, the semantic relative structure and the semantic constraint information are linked together; And the methods of semantic feature self-organized evolution are classified. Finally, combining a design example of domestic high-speed elevator, how to apply the theory to practical product development is illustrated and this method and its validity is described and verified. According to the study results, the designers are able to represent the design intents at an advanced semantic level in a more intuitional and natural way and the automation, recursion and visualization for mechanical product axiomatic design are also realized.

关键词： Axiomatic design Semantic feature Design intent Self-organized

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Sliding Mode Control with Auto-Tuning Law for Maglev System

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Engineering（科研） 2010年第2期2卷 107-112页

作者： L.L. zhang z.z. zhang z.Q. Long A.M. hao 不详

This paper presents a control strategy for maglev system based on the sliding mode controller with auto-tuning law. The designed adaptive controller will replace the conventional sliding mode control (SMC) to eliminate the chattering resulting from the SMC. The stability of maglev system is ensured based on the Lyapunov theory. Simulation results verify the effectiveness of the proposed method. In addition, the advantages of the proposed controller are indicated in comparison with a traditional sliding mode controller.

关键词： Sliding Mode Control Maglev System Lyapunov Theory Auto-Tuning

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Ori-Finder 2022:A Comprehensive Web Server for Prediction and Analysis of Bacterial Replication Origins

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genomics, Proteomics & Bioinformatics 2022年第6期20卷 1207-1213页

作者： Mei-Jing Dong hao Luo Feng gao Department of Physics School of ScienceTianjin UniversityTianjin 300072China Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(Ministry of Education) Tianjin UniversityTianjin 300072China SynBio Research Platform Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)Tianjin 300072China

The replication of DNA is a complex biological process that is essential for *** DNA replication is initiated at genomic loci referred to as replication origins(oriCs).Integrating the z-curve method,DnaA box distribution,and comparative genomic analysis,we developed a web server to predict bacterial oriCs in 2008 called Ori-Finder,which is helpful to clarify the characteristics of bacterial *** oriCs of hundreds of sequenced bacterial genomes have been annotated in the genome reports using Ori-Finder and the predicted results have been deposited in DoriC,a manually curated database of *** has facilitated large-scale data mining of functional elements in oriCs and strand-biased ***,we describe Ori-Finder 2022 with updated prediction framework,interactive visualization module,new analysis module,and user-friendly *** species-specific indicator genes and functional elements of oriCs are integrated into the updated framework,which has also been redesigned to predict oriCs in draft *** interactive visualization module displays more genomic information related to oriCs and their functional *** analysis module includes regulatory protein annotation,repeat sequence discovery,homologous oriC search,and strand-biased *** redesigned interface provides additional customization options for oriC ***-Finder 2022 is freely available at http://***/Ori-Finder/and https://***/Ori-Finder/.

关键词： Bacteria DNA replication Replication origin z-curve DnaA-trio

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Equivalent continuum modeling of beam-like truss structures with flexible joints

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Acta Mechanica Sinica 2019年第5期35卷 1067-1078页

作者： Fushou Liu Libin Wang Dongping Jin hao Wen College of Civil Engineering Nanjing Forestry UniversityNanjing 210037China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The paper investigated the equivalent continuum modeling of beam-like repetitive truss structures considering the flexibility of joints,which models the contact between the truss member and joint by spring-damper with six directional stiffnesses and ***,a two-node hybrid joint-beam element was derived for modeling the truss member with flexible end joints,and a condensed model for the repeating element with flexible joints was ***,the energy equivalence method was adopted to equivalently model the truss structure with flexible joints and material damping as a spatial viscoelastic anisotropic beam ***,the equations of motion for the equivalent beam model were derived and solved analytically in the frequency *** the numerical studies,the correctness of the presented method was verified by comparisons of the natural frequencies and frequency responses evaluated by the equivalent beam model with the results of the finite element method model.

关键词： Large space truss structure Flexible joint Equivalent continuum modeling Anisotropic beam model Frequency response

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